Download Contact Lens Spectrum

Contact Lens
SPECTRUM
S
P
E
C
I
A
L
E
D
I
T
I
O
N
2
0
1
®
4
www.clspectrum.com
Breaking the
Cycle of Discomfort
Advanced contact lens materials and manufacturing
process deliver exceptional comfort*
ALSO IN THIS ISSUE
■ Contact Lens Discomfort Defined
■ Preventing Dehydration Blur
■ Growing a Practice With a Novel Contact Lens Technology
Sponsored by
Best-in-class properties
for best-in-class performance
1
Bausch + Lomb ULTRA® contact lenses with MoistureSeal® technology
combine best-in-class physical properties for a revolutionary silicone hydrogel lens.1
Dk/t
MODULUS
ASPHERIC
OPTICS
THIN EDGE
DESIGN
Bausch + Lomb ULTRA®
contact lenses
163
70
3
3
ACUVUE OASYS
147
73
138
102
160
82
AIR OPTIX AQUA
Biofinity
3
Patient
preferred for
end-of-day
comfort
over the leading
silicone hydrogel lenses2
2 to 1
vs.
ACUVUE OASYS
3 to 1
vs.
AIR OPTIX AQUA
3
4 to 1
vs.
Biofinity
Retains moisture for a full 16 hours.1
Go to www.blultra.com or contact a Bausch + Lomb sales representative today
REFERENCES: 1. Data on file. Bausch & Lomb Incorporated. Rochester NY; 2013. 2. Results from a 22-investigator, multi-site study of Bausch + Lomb Ultra
contact lenses with MoistureSeal technology, on 327 current silicone hydrogel lens wearers. After 7 days of wear, subjects completed an online survey. Subjects
rated performance across a range of attributes. Preference comparisons represent only those subjects expressing a preference. Ratio is based on the average
across the silicone hydrogel lenses represented in the study.
®/™ are trademarks of Bausch & Lomb Incorporated or its affiliates. All other product/brand names are trademarks of their respective owners.
©2014 Bausch & Lomb Incorporated. US/ZUS/14/0149
Special Edition
2
V
O
L
U
M
E
2
9
N
U
M
B
E
0
R
1
1
4
3
F E A T U R E S
18
23
30
Contact Lens Discomfort Defined
PVP
By Katherine M. Bickle, OD, MS & Kelly K. Nichols, OD,
MPH, PhD
Each year, patients in our practices are struggling with
lens wear, and in some cases, dropping silently out of lens
wear. How do we get to the bottom of this problem?
Si
A
Breaking the Cycle of Discomfort
By Katarzyna Wygladacz, MS, PhD;
Daniel Hook, BS, MS, PhD; Robert Steffen, OD, MS
& William Reindel, OD, MS
Advanced contact lens materials and manufacturing
process deliver exceptional comfort.*
Si
PVP
B
Clinical Performance of Samfilcon A
Silicone Hydrogel Contact Lenses
By Robert Steffen, OD, MS; Mohinder M. Merchea, OD,
PhD, MBA; Marjorie J. Rah, OD, PhD &
William Reindel, OD, MS
Different approaches for PVP
entanglement PAGE 26
New technology aims to make lens wear more
comfortable despite increased digital viewing.
39
44
Preventing Dehydration Blur
By Kristen R. Hovinga, MS; Paul D. Ludington, MS,
Mohinder Merchea, OD, PhD, MBA, & Robert Steffen, OD, MS
The increased use of digital devices in today’s society
has made it more important than ever to address lens
dehydration.
A One-Step Hydrogen Peroxide-based
Contact Lens Solution
By Kimberly A. Millard, MS; Daniel Hook, PhD;
Andrew Hoteling, PhD & Katarzyna Wygladacz, PhD
Development of a cleaning and disinfecting solution with
a platinum-modulating compound.
49
Growing My Practice With a Novel
Contact Lens Technology
D E P A R T M E N T S
5 Editor’s Perspective
By Jason J. Nichols, OD, MPH,
PhD, FAAO
New Concepts Aimed at Improving
Vision and Comfort
6 Research Review
By S. Barry Eiden, OD, FAAO
Research About the Ocular Surface
and Contact Lens Wear
9 Refractive Focus
By Katherine M. Bickle, OD, MS &
David Berntsen, OD, PhD, FAAO
The Impact of Dry Eye on Visual
Performance
By Matthew Ward, OD
Even when patients say, “I’m happy with the lens I have.”
*MoistureSeal technology, as part of the Bausch + Lomb Ultra contact lens material
(samfilcon A), represents a significant achievement in integrating novel material chemistry
and a two-phase manufacturing process to produce a unique silicone hydrogel lens designed to
address the cycle of discomfort many wearers encounter each day and enhance the overall lens
wearing experience particularly at the end of the day.
Contact Lens
SPECTRUM
®
Contact Lens
SPECTRUM
EDITOR-IN-CHIEF
Jason J. Nichols, OD, MPH, PhD, FAAO
2008-Present
CLINICAL FEATURES EDITOR
Edward S. Bennett, OD, MSEd, FAAO
2007-Present
MANAGING EDITOR
Lisa Starcher
(215) 367-2168
[email protected]
ASSISTANT EDITOR
Deborah Fisher
SPECIAL PROJECTS
EDITORIAL DIRECTOR Angela Jackson
(215) 628-6589
[email protected]
®
Special Edition
2
V
D
EDITORS EMERITUS
Joseph T. Barr, OD, MS, FAAO
1987-2007
Carla J. Mack, OD, MBA, FAAO
2007-2008
Research Review
S. Barry Eiden, OD, FAAO
Eric Papas, PhD, MCOptom, DipCL FAAO
Refractive Focus
David A. Berntsen, OD, PhD, FAAO
Jason Marsack, PhD
Prescribing for Presbyopia/Astigmatism
Timothy B. Edrington, OD, MS, FAAO
Craig W. Norman, FCLSA
Thomas G. Quinn, OD, MS, FAAO
GP Insights
Edward S. Bennett, OD, MSEd, FAAO
John Mark Jackson, OD, MS, FAAO
Contact Lens Design & Materials
David L. Kading, OD, FAAO
Neil Pence, OD, FAAO
Ronald K. Watanabe, OD, FAAO
Dry Eye Dx and Tx
Amber Gaume Giannoni, OD, FAAO
Katherine M. Mastrota, MS, OD, FAAO
William Townsend, OD, FAAO
Contact Lens Care & Compliance
Susan J. Gromacki, OD, MS, FAAO
Michael A. Ward, MMSc, FAAO
Contact Lens Practice Pearls
Jessica H. Mathew, OD, PhD, FAAO
Jason R. Miller, OD, MBA, FAAO
Gregory J. Nixon, OD, FAAO
Is This the New Norm?
Mile Brujic, OD
David L. Kading, OD, FAAO
The Business of Contact Lenses
Gary Gerber, OD
Clarke D. Newman, OD, FAAO
Pediatric and Teen CL Care
Christine W. Sindt, OD, FAAO
Jeffrey J. Walline, OD, PhD, FAAO
The Scleral Lens Vault
Gregory W. DeNaeyer, OD, FAAO
Treatment Plan
William L. Miller, OD, MS, PhD, FAAO
Leo Semes, OD, FAAO
Contact Lens Case Reports
Mark P. André, FAAO
Patrick J. Caroline, FAAO
E-mail: [email protected]
Home page: www.clspectrum.com
P
U
M
A
E
R
2
T
9
N
M
E
By Thomas G. Quinn, OD, MS, FAAO
Patient Characteristics Affect
Multifocal Lens Performance
12 GP Insights
By Edward S. Bennett, OD, MSEd, FAAO
Using Peroxide With GP Lenses
13
Contact Lens Design & Materials
By Neil Pence, OD, FAAO
Characteristics of a New Silicone
Hydrogel Contact Lens
COLUMNISTS
Online Photo Diagnosis
Luciano Bastos
Gregory W. DeNaeyer, OD, FAAO
William Townsend, OD, FAAO
L
11 Prescribing for Presbyopia
EDITOR/PROJECT MANAGER Leslie Goldberg
FOUNDING EDITOR
Neal J. Bailey, OD, PhD
1986-1987
E
O
14
Dry Eye Dx and Tx
U
M
N
B
T
0
1
R
1
E
4
3
S
53 The Business of Contact
Lenses
By Gary Gerber, OD
Assessing the Value of Adding
New Technology
54 Pediatric & Teen CL Care
By Jeffrey J. Walline, OD, PhD, FAAO
Myopia Control Consent Form
55 Treatment Plan
By William L. Miller, OD, MS, PhD,
FAAO
Learnings from the Contact Lens
Discomfort Workshop
By Katherine M. Mastrota, MS, OD, FAAO
Ocular Surface and Tear Film
in Contact Lens Discomfort
15 Contact Lens Care & Compliance
By Michael A. Ward, MMSC, FAAO
New Option for Peroxide
Disinfection
52 Contact Lens Practice Pearls
By Jason R. Miller, OD, MBA, FAAO
Contact Lens
SPECTRUM
®
The Contact Lens Conversation
PUBLISHER, OPTOMETRIC PUBLICATIONS
Roger Zimmer
(203) 846-2827 • [email protected]
ADVERTISING SALES
Scott Schmidt, Eastern Regional Sales Manager
(610) 564-7237 • [email protected]
Jacqui DiBianca, Western Region Senior Account Manager
(610) 662-9735 • [email protected]
Audrey Krenzel, Classified/Resource Center Advertising
and Reprints
(215) 367-2184 • [email protected]
Julia Eisenhandler, Account Executive
(215) 628-7714 • [email protected]
E-MEDIA SALES
Rob Verna, National Account Manager
(215) 367-2179 • [email protected]
SUBSCRIPTION INQUIRIES/ADDRESS CHANGES
(800) 306-6332 • Fax (847) 564-9453 • [email protected]
EDITORIAL, PRODUCTION, AND SALES OFFICES:
PentaVision LLC
321 Norristown Road, Suite 150
Ambler, PA 19002
(267) 492-5200 • Fax: (215) 367-2145
PENTAVISION CONFERENCE GROUP
Maureen Platt
(215) 628-7754 • [email protected]
PENTAVISION LLC
PRESIDENT Thomas J. Wilson
EXECUTIVE VICE PRESIDENTS
Mark Durrick, Douglas Parry, Robert Verna,
Roger Zimmer
PRODUCTION DIRECTOR Sandra Kaden
ART DIRECTOR William Pfaff
PRODUCTION MANAGER Bill Hallman
(215) 628-6585 • [email protected]
MARKETING MANAGER Amy Wauhop
PROMOTIONAL EVENTS MANAGER Michelle Kieffer
Body stock only
A Proud Supporter of
Make wearing lenses easier
on your patients’ eyes
1
RECOMMEND BIOTRUE
The multi-purpose solution that works like your eyes
®
matches the pH of healthy tears
utilizes a lubricant found in the eyes
keeps key beneficial tear proteins active
No wonder 9 out of 10 patients prefer
Biotrue over the leading multi-purpose solution2
biotrue.com
Based on patient satisfaction study.
Based on 2855 multi-purpose users asked to try Biotrue for about 7 days.
© 2014 Bausch & Lomb Incorporated. ®/™ are trademarks of Bausch & Lomb Incorporated or its affiliates. PNS07238
1
2
HL6195
Two approaches
to treating irregular corneas
with custom soft lenses.
In its time
In its prime
Thickness of material
Anterior aspheric optics
.51mm
•
CONVENTIONAL DESIGN†
.39mm
•
KERASOFT IC PATENTED DESIGN†
†Images represent horizontal scan of -3.00D lenses. KeraSoft® IC uses prism ballasting.
KeraSoft® IC. The prime time approach.
When treating irregular corneas with a soft lens, there was a time when “thickness of material” was
thought to be the best approach. Today, there is KeraSoft® IC. Its patented design “drapes” over the
cornea to correct the vision rather than simply “mask” the irregularity. This enables KeraSoft® IC to
have a thinner optical center than in traditional designs, while still providing excellent visual acuity – a
significant factor to consider when choosing a lens that meets your patient’s needs. And for comfort,
KeraSoft® IC is made of a quarterly replacement silicone hydrogel*.
*Definitive Material.
When fitting the KeraSoft® IC soft contact lens,
the MoRoCCo VA App can help. Visit kerasoftic.com for details.
Don't mask the problem.
ONLY FROM AUTHORIZED LABORATORIES
Definitive is a trademark of CONTAMAC US, INC.
©2014 Bausch & Lomb Incorporated. KeraSoft is a trademark of
Bausch & Lomb Incorporated or its affiliates. US/KER/14/0003
editor’s perspective
B Y
J A S O N
J .
N I C H O L S ,
O D ,
M P H ,
P H D ,
F A A O
New Concepts
Aimed at Improving
Vision and Comfort
T
echnology is continually expanding and moving boundaries for us
in all aspects of our lives. It is truly amazing and exciting to see the
conveniences that new technologies afford us each day. On the
other hand, technology creates occasional headaches — literally
and figuratively in the medical sense.
Computers and other digital devices and their use, particularly
over long periods of time, are clinically associated with a variety of
ophthalmic-related conditions including headaches, eyestrain and
fatigue, discomfort and dry eye. It is thought by some that these
problems are further exacerbated by the use of contact lenses, but
this is not entirely clear. There is no doubt that the optical quality
and vision-related performance of a contact lens depends on a
stable pre-lens tear film.
This special edition of Contact Lens Spectrum explores some of the
challenges we face when patients come to us with complaints of fatigue,
discomfort and the like.
Often, these problems are a challenge to manage given that
employment or social needs mandate our patients’ use of technology.
We as eye care practitioners need contact lens materials and designs
that will help us overcome these challenges, allowing our patients to
wear contact lenses in a variety of environments. In this special edition,
you can learn more about one such technology, aimed at improving the
wearing experience of our patients who use digital devices. I applaud
manufacturers who are working to improve contact lens materials and
designs that will allow for more satisfied patients and greater success in
contact lens practice.
Contact Lens Spectrum (ISSN 0885-9175) is a registered trademark of PentaVision LLC, published monthly with a
special October 2014 edition. Advertising and editorial office: 321 Norristown Rd., Suite 150, Ambler, PA 19002. Subscriptions: United States 1 year $63, 2 years $111; Canada 1 year $80, 2 years $145. Other countries 1 year $118, 2 years $210
(must be prepaid in U.S. dollars). Single copies $8 each for the United States and Canada, $10 for all other locations. Periodicals postage paid at Ambler, PA and additional mailing office. Copyright 2014 by PentaVision. Reproduction of all or
part of this publication without the consent of the publisher is prohibited. For subscription information/address changes:
Contact Lens Spectrum, P.O. Box 3076, Northbrook, IL 60065; (800) 306-6332 or Fax (847) 564-9453.
POSTMASTER: If undeliverable, send form 3579 to Contact Lens Spectrum, P.O. Box 3076, Northbrook, IL 60065.
w w w. c l s p e c t r u m . c o m
Acceptance and publication of advertisement, news story, or product information does not imply endorsement of
any company, product or service by PentaVision. Information that is beneficial to practitioners often is compiled by
individuals who have manufacturing ties. Because of the authors’ economic interest in a particular company, reports
of this type may reflect bias. Publication of such information is a service to our readers and in no way implies product
endorsement by this magazine.
Canada Post International Publication Mail (Canadian Distribution) Sales Agreement# IPM0601535.
If undeliverable in Canada, return to: PentaVision, c/o N.I., P.O. Box 44
RPO Rockwood Mall, Mississauga, ON L4W 9Z9.
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
5
Research Review
B Y
S .
B A R R Y
E I D E N ,
O D ,
F A A O
Research About the Ocular
Surface and Contact Lens Wear
O
ur understanding of the critical importance of a
healthy ocular surface for successful contact lens
wear is becoming more apparent as research
continues to tell us of the intimate relationship
between the two. Over the past
few years, landmark efforts have
been made to clarify our understanding of this relationship as
expressed by three international
workshops held by the Tear Film
and Ocular Surface Society
(TFOS):
1. The International Dry
Eye Workshop (DEWS) 2007
(DEWS Report, 2007)
2. The International Workshop on Meibomian Gland
Dysfunction 2011 (Nichols et al,
2011)
3. The International Workshop on Contact Lens Discomfort
2013 (Nichols et al, 2013)
These workshops each brought
together the leading experts in
their fields to organize current
knowledge and encapsulate current approaches to diagnosis and
management of these clinically
challenging entities. As stated by
the authors, “The International
workshops provide a consensus
overview of the field as a snapshot in time.” The documents
published are based on extensive
international literature reviews of
current research. They give us a
heretofore unavailable evidencebased foundation from which
ongoing research will allow us
6
■
to continue to better understand
how to manage patients with
ocular surface disease (with or
without contact lens wear). Let’s
look at some of the most current
research in this area and see how
it furthers our understanding.
General Perspectives of Dry
Eye and Ocular Surface Disease
A recent publication authored
by many of the original DEWS
participants evaluated where
we are in the understanding of
dry eye disease (DED) since
the original DEWS report was
published in 2007 (Bron et al).
They once again reviewed some
of the most impactful research
studies over the past 5 years.
The authors made a number of
key clinical conclusions following their literature review, which
suggested that a rethinking of
traditional concepts of dry eye is
needed. They stated that “DED
is not simply an inconvenience,
but rather a bonafide disease with
important clinical implications.”
Further, DED has two major subtypes, aqueous deficient dry eye
(ADDE) and evaporative dry eye
(EDE), the most common form
of which is meibomian gland dysfunction (MGD). A critical con-
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
clusion was that although most
patients present with symptoms,
a significant number of patients
with objective evidence of disease
are asymptomatic. Diagnosis by
symptoms alone is insufficient.
Additionally, all objective tests
for DED are variable in patients
with DED. This variability isn’t
seen in healthy individuals. As an
example, with effective treatment,
tear osmolarity has been reported
to return to normal, and the
variability found prior to treatment is reduced. Finally, the
authors stated that many new
therapeutic approaches are under
development, including antiinflammatory agents, secretory
stimulants, tear film stabilizers,
and others. With incorporation of
improved endpoints for clinical
trials, it’s likely that a variety of
therapeutic agents will emerge in
the foreseeable future.
Taking a simpler approach,
a group of European dry eye
experts (ODISSEY European
Consensus Group) met to come
up with a consensus approach to
the diagnosis and severity grading of dry eye disease (Baudouin
et al, 2014). The authors stated
that due to its multifactorial
nature, clinical and biological
signs of DED can be inconsistent and sometimes discordant
with symptomatology. Using a
consensus-based approach, the
group assessed 14 commonly used
DED severity criteria. The panel
agreed that following confirmed
DED diagnosis, just two critew w w. c l s p e c t r u m . c o m
ria, symptom-based assessment
and corneal fluorescein staining
were sufficient to diagnose the
presence of severe DED in the
majority of patients. In the event
of discordance between signs and
symptoms, further evaluation
using additional determinant
criteria was recommended.
Evolving Technologies in the
Diagnosis of Dry Eye Disease
A review of currently available and emerging technologies
utilized in the diagnosis and
evaluation of dry eye disease was
recently published. In addition to
a group of commonly performed
diagnostic tests and procedures,
the authors reviewed a number
of new technologies in development (Zeev et al, 2014). Optical
coherence tomography (OCT)
of the anterior segment is able to
measure the inferior tear meniscus height with the advantage of
being objective, reproducible and
non-invasive. A developing system
for tear meniscus height measures
utilizes reflective meniscometry.
Measured with a slit lamp-mounted instrument, this technology
seems to be as reliable as OCT
— but much less expensive. Tear
film stability can be measured using modified videokeratography
systems. The software analyzes
dynamic changes in tear film
stability over a 10 second time
period and quantifies the results
with measures of surface regularity and surface asymmetry. Similarly, aberrometry is being used
to evaluate dry eye influences on
higher order aberrations (HOAs),
both in terms of overall degrees of
HOAs as well as dynamic changes
in HOAs over specific time periods. Tear film interferometry
measures the lipid layer thickness,
w w w. c l s p e c t r u m . c o m
which is reduced in cases of MGD
and EDE. Some instruments
such as LipiView (Tear Science)
can quantify lipid layer thickness
while other less expensive systems such as the Keratograph 5M
(Oculus) can record video images
of the lipid layer, and via subjective observation of the bifringence
color pattern, lipid layer thickness
can be estimated. Meibomography
allows the clinician to view the
meibomian glands (MGs). A number of systems (such as the Keratograph 5M) have been developed
and grading scales determining
the degree of MG loss (atrophy)
have been proposed. Biomarkers
in the tear film can be measured
clinically to provide diagnostic
information regarding ocular
surface disease. For example, the
recently introduced InflammaDry
test (Rapid Pathogen Screening)
detects elevated levels of matrix
metalloproteinase-9 in the tear
film, which is an inflammatory
biomarker common to dry eye.
Measurements of lactoferrin and
IGE in the tear film as measured
by the TearScan Microassay System (Advanced Tear Diagnostics)
can help the clinician differentiate
allergic eye findings from dry eye
or determine that both are present. Ocular surface and tear film
temperature diurnal variations
have been shown to be greater in
dry eye disease as compared to
normal eyes. Ocular surface thermography systems have been introduced that may have diagnostic
value in DED.
MGD, Dry Eye and Contact
Lens Wear
The relationship between MGD
and dry eye has been conclusively shown to be strong. In fact,
the authors of the International
Workshop on Meibomian Gland
Dysfunction state that MGD is
now considered the leading cause
of dry eye (Nichols et al, 2011).
Ongoing research into MGD is
allowing us to better diagnose and
treat this condition.
Recently, researchers in China
again confirmed the relationship between MGD and dry eye
(Feng et al, 2014). 264 randomly
selected patients (528 eyes) suffering from dry eye disease were
enrolled in the study. Tear-film
break-up time (TBUT) was measured and tear-film production
was evaluated by the Schirmer
test I (SIT). Subjective symptoms
were also scored. Meibomian
glands were observed using a
non-contact meibography system.
Meibomian dropout was scored
for each eyelid. SIT and TBUT
were significantly negatively correlated with the meibomian gland
photographic score, whereas
corneal fluorescein staining was
positively correlated. The authors
concluded that a large proportion
of meibomian dropout cases were
found among patients with DED,
indicating that treatment targeted
at the meibomian gland will continue to be an important direction
for treating DED. They felt that
meibography is recommended as
a routine test for dry eye disease.
A Japanese study evaluated the
relationship between contact lens
wear and meibomian gland drop
out (Arita et al, 2009). A group of
contact lens wearers and an age
matched group of non-contact
lens wearing healthy controls
were evaluated with the following
tests: slit-lamp examinations of
the eyelids, corneal and conjunctival staining using fluorescein,
measurement of tear film TBUT,
noncontact meibography, and
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
7
Research Review
measurement of tear production using the Schirmer I test.
Results showed the meiboscore,
which measures meibomian gland
drop out, was significantly higher
(P<0.0001) in CL wearers than in
the control group. The average
meiboscore of CL wearers was
similar to that of a 60- to 69-yearold age group from the normal
population. A significant positive
correlation was observed between
the duration of CL wear and the
meiboscore. Contact lens wear
was associated with a decrease in
the number of functional meibomian glands and this decrease was
proportional to the duration of
CL wear.
Contact Lenses and Dry Eye
Dry eye symptoms are one of the
most common complaints from
contact lens wearers and have
been reported to be a major reason for discontinuation and drop
out from contact lens wear. A
multicenter prospective study was
conducted that evaluated a group
of soft contact lens (SCL) wearers
who reported significant SCLrelated dryness symptoms (Young
et al, 2012). The group was comprised of both patients with definitive ocular signs of dryness and
patients with no observable signs
of dryness. The symptomatic SCL
wearers reported significant SCLrelated dryness symptoms via a
self-administered questionnaire of
frequency and intensity of dryness
following a dry eye (DE) physical
eye examination. DE etiology was
assigned post hoc by an expert
panel, and those with and without
significant DE-related signs were
analyzed by univariate logistic
regression. Possible DE etiologies were aqueous tear deficiency,
SCL-induced tear instability,
8
■
meibomian gland dysfunction, or
“other.” Wearers without signs
that qualified for any DE etiology
were designated as No DE Signs
(NDES). Results indicated that of
the 226 SCL symptomatic wearers examined, 23% were without
signs, 30% had evidence of aqueous tear deficiency, 25% had evidence of SCL-induced tear instability, 14% had meibomian gland
dysfunction, and 8% had “other”
diagnoses. The NDES wearers
were significantly more likely to
be male (36% vs.19%, p = 0.013),
Contact lens
wearers commonly
suffer from dry eye
symptoms that can
be associated with
ocular surface
disease and
exacerbated by
contact lens wear.
were less likely to have deteriorating comfort during the day (81%
vs. 97%, p = 0.001) and reported
longer average hours of comfortable wear (11 ± 3 vs. 9 ± 4 h,
p = 0.014). The researchers concluded that symptoms of dryness
in SCL wearers stem from a variety of underlying causes. However, nearly one-quarter of these
symptomatic SCL wearers appear
to be free of clinical signs of dryness. They stated that the effective management of CL-related
dryness requires a comprehensive
range of clinical assessments and
the use of a diverse range of man-
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
agement strategies.
Over the past number of years,
there has been a great resurgence in the fitting of scleral gas
permeable contact lenses. One
of the key proposed indications
for scleral lens fitting is for the
management of ocular surface
diseases. A retrospective study
was conducted at a tertiary referral center in order to describe the
management of ocular surface
disease with commercially available scleral lenses (Schornack et
al, 2014). Researchers reviewed
the medical records and analyzed
a survey mailed to all patients
who completed the scleral lens
fitting process to evaluate the
long-term success of scleral lens
therapy in the management of
ocular surface disease. Of the 212
subjects, 115 (188 eyes) successfully completed the scleral lens
fitting process, and therapeutic
goals (improved comfort, ocular
surface protection, or resolution
of keratopathy) were achieved in
all but 2 of these subjects. Visual
acuity improved with scleral lens
wear when compared to habitual
correction. The most common
indications for scleral lens therapy
were undifferentiated ocular surface disease, exposure keratopathy,
and neurotrophic keratopathy.
Subjects had attempted an average of 3.2 (range, 0-8) other forms
of intervention before scleral
lens wear. Scleral lens fitting was
completed in an average of 3 visits
(range, 2-6), with an average of
1.4 lenses/eye (range, 1-4). Three
patients experienced complications during scleral lens wear that
resolved without loss of visual
acuity, enabling resumption of
scleral lens wear. The conclusions
of this study are that commercial(Continued on page 10)
w w w. c l s p e c t r u m . c o m
Refractive Focus
BY K ATHERINE M. BICKLE, OD, MS, & DAVID A . BERNTSEN, OD, PHD, FA AO
The Impact of Dry Eye on
Visual Performance
A
A significant number of patients experience dry
eye disease (DED) and seek relief of their dry
eye symptoms. Beyond the subjective symptoms of DED, what do we know about the
effect of DED-related visual disturbances on our patients’ daily
activities?
Between 5-30% of individuals are estimated to have DED
(McCarty et al, 1998; Lin et al,
2003). DED can be challenging
for not only the patient but for
the eye care professional diagnosing and implementing treatment
due to the lack of correlation
between signs and symptoms
(Nichols et al, 2004). There is not
one specific test that definitively
confirms a DED diagnosis. Tear
film instability (Tutt et al, 2000;
Montes-Mico et al, 2004; Begley
et al, 2006) and a decreased tear
break-up time can cause transient
visual disturbances, while centrally located superficial punctate
keratitis can result in constant
symptoms that include decreased
visual acuity (Huang et al, 2002)
and decreased reading speed
(Ridder 3rd et al, 2013).
Eye care providers strive to
find an appropriate balance when
factoring in patient signs and
symptoms to properly diagnose
and treat their patients. Visual
symptoms for dry eye patients can
vary dramatically in frequency
and severity. The differences in
visual demands, which are unique
w w w. c l s p e c t r u m . c o m
to each patient, make it difficult
to test patients under their specific conditions in an exam room
setting. However, this should not
discourage you from obtaining
a thorough history to determine
the conditions in which your pa-
those with definite DED (4.82%)
compared to those without DED
(3.56%). Factoring in the average
annual salary of the employees
affected by DED, they estimated
wage losses of $1,178 with overall company production losses
averaging $6,160. Reductions
in time management and both
mental and interpersonal function were also found to be related
to DED, demonstrating that the
impact of patients’ symptoms on
everyday life can be dramatic. By
understanding and treating your
The differences in visual demands, which are
unique to each patient, make it difficult to
test patients under their specific conditions
in an exam room setting.
tients are most bothered by visual
disturbances and their impact on
the patient’s daily life. A patient
may report blurred vision, yet is
able to read 20/20. How might
this influence their work performance?
patient’s symptoms, we are not
only making them more comfortable but also potentially reducing
workplace productivity loss. What
about the influence of DED on
non-work activities?
The Economic Burden
Driving response times are slower
in patients with DED than those
without DED (Deschamps et al,
2013). Response times have been
shown to be correlated with corneal higher-order aberrations,
indicating that disruptions in the
tear film may play a factor in driv-
A recent study conducted in
Japan evaluated work productivity and performance in those
without DED, probable DED,
and definite DED (Uchino et al,
2014). Total workplace productivity loss was slightly greater in
Dry Eye Disease and Daily Life
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
9
Refractive Focus
ing safety. While we often consider how clinical signs or symptoms
(e.g., dryness, burning, irritation,
redness, and grittiness) will improve with various treatment options, we should also consider the
impact this will potentially have
on the patient’s quality of life and
safety.
While patients with DED may
complain of visual fluctuations,
why might you not find reduc-
The effect of DED
on visual function
is more likely to be
observed when
functional factors
such as reading
speed are evaluated.
tions in visual acuity during your
examination? While DED can
disrupt the tear film, patients
are able to blink and re-establish
the tear film momentarily during these tasks so that you do not
detect a reduction in visual acuity
(Ridder 3rd et al, 2013). However,
the effect of DED on visual function is more likely to be observed
when functional factors such
as reading speed are evaluated.
Average reading speed for DED
patients (134.9 words per minute)
have been shown to be slower
than for normal patients (158.3
words per minute), demonstrating
the functional effect of DED on
daily visual tasks. How can you be
most effective and efficient at
understanding the symptoms of
this type of patient?
Application in the
Clinical Setting
Understanding specific situations in which patients have been
10
■
shown to experience visual disturbances due to DED allows
you to ask targeted questions
(e.g., questions related to reading, driving, use of electronic
devices, etc.). This can help you
better understand the patient
who reports sometimes vague
issues regarding visual performance but has 20/20 Snellen
acuity. Questionnaires can also
be administered by your staff to
quickly address specific DEDrelated questions. Being able to
review the patient’s responses
prior to your examination allows
for a more efficient and targeted
patient history. DED patients are
more likely to report difficulties
with reading (odds ratio [OR] =
3.64), watching television (OR=
2.84), completing professional
work (OR= 3.49), and driving
during the day (OR = 2.80) and
night (OR=2.20) on surveys
(Miljanovic et al, 2007). At
follow-up visits, patients can
complete the same questionnaires
to assess for improvements in
these areas after treatment.
In summary, studies demonstrating a relationship between
symptoms and daily tasks can aid
in asking targeted questions about
difficulties that your dry eye
patients may experience but do
not know how to report during an
eye examination. Understanding
these relationships can allow you
to more effectively identify
DED-related issues so that you
can quickly diagnose and treat
these patients. CLS
For references, please visit www.
clspectrum.com/references.asp and
click on document #SE2014.
Dr. Bickle is a PhD student at The Ohio State
University College of Optometry and is in private practice in Granville, Ohio. Dr. Berntsen
is an assistant professor at the University
of Houston College of Optometry. He has
received research funding from the Johnson &
Johnson Vision Care Institute and Alcon.
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
Research Review
(Continued from page 8)
ly available scleral lenses can be
successfully used in the management of moderate to severe ocular
surface disease. The scleral lens
fitting process can be completed
efficiently for most eyes by using
diagnostic trial lenses. In addition
to protecting the ocular surface,
scleral lenses improve visual acuity in patients whose surface disease has compromised vision.
Conclusion
Ocular surface disease and specifically DED is a major challenge to
both eye care practitioners and to
their patients. Contact lens wearers commonly suffer from dry eye
symptoms that can be associated
with ocular surface disease and
exacerbated by contact lens wear.
Ongoing research gives us a much
clearer understanding of these
diseases and their relationship to
contact lens wear. Outcomes from
this research allow us as eye care
practitioners to better manage
our patients and allow them to
experience clear, comfortable and
healthy vision with contact lens
wear. CLS
For references, please visit www.
clspectrum.com/references and click
on document #SE2014.
Dr. Eiden is president and medical director of
North Suburban Vision Consultants, president
and medical director of the National Keratoconus Institute, and co-founder of EyeVis Eye
and Vision Research Institute. He is an adjunct
faculty member at The University of Illinois
Medical Center, as well as at the Indiana and
Illinois Colleges of Optometry and Pennsylvania College of Optometry at Salus University.
He is also a consultant or an advisor to Alcon,
Alden Optical, Bausch + Lomb, CooperVision,
Diopsys, Oculus, Paragon Vision Sciences,
SpecialEyes and Visionary Optics.
w w w. c l s p e c t r u m . c o m
Prescribing for Presbyopia
B
Y
T
H
O
M
A
S
G
.
Q
U
I
N
N
,
O
D
,
M
S
,
F
A
A
O
Patient Characteristics Affect
Multifocal Lens Performance
I
t’s common to consider lens design features
when choosing a multifocal contact lens, but
individual patient characteristics should be
considered as well. Most contact lens fitters
understand the importance of
pupil size and how it impacts the
information received by the visual
system through a simultaneous vision multifocal contact lens. Pupil
size is one of the primary reasons
it’s best to over-refract a simultaneous vision multifocal lens using
loose lenses. Over-refracting behind a phoropter likely will lead
to relative pupil dilation compared to what would be present in
a more natural environment.
Although pupil size decreases
with age, the change in size with
illumination follows a similar
slope for all age groups (Plainis
et al, Oct. 2013). It is therefore
important to consider light level
when assessing multifocal contact
lens performance on presbyopes
of all ages.
Advancing age offers some
benefits in that at least one study
found subjects with small pupils
to have better near vision than
their counterparts when wearing
a center near soft multifocal lens
design (Plainis et al, Jan. 2013).
Spherical Aberration
The good news for the more
advanced presbyope with regard
to pupil size is tempered, at least
somewhat, by changes in ocular
w w w. c l s p e c t r u m . c o m
spherical aberration over time.
The same study that evaluated
the impact of pupil size on visual
performance of a center near
soft multifocal lens also found
a decrease in near acuity with
higher levels of ocular spherical
aberration, which, unfortunately,
increases with age.
Degree of Presbyopia
Of course, where the patient is
along the presbyopic spectrum
has a huge impact on the performance of simultaneous vision
design multifocal contact lenses.
One study evaluated the performance of three different soft
multifocal designs (Acuvue Oasys
for Presbyopia, Air Optix Aqua
Multifocal, Biofinity Multifocal)
on a group of low add (ages 40
to 45 years) patients (Vasudevan,
2013). No statistically significant
differences in accommodative
response, measured optical aberrations, or in visual performance
were found between the lenses.
However, with advancing
presbyopia, there is greater likelihood that distance and near correction will interfere with each
other. This commonly requires
biasing one eye for distance and
the other for near to meet most
of the patients’ visual needs with
a multifocal contact lens. Ocular
dominance can play a role in determining which eye is biased for
distance and which for near.
Ocular Dominance
Many contact lens providers assess ocular dominance by asking
patients to line up an object while
looking through outstretched
hands, a tube, a camera, or some
other similar device. This form of
testing determines sighting dominance, which is a measure of how
the body is wired, similar to identifying the dominant hand (right
or left). Schor and colleagues
(1987) found ocular dominance
determined via this method has
little correlation with monovision
or multifocal lens success.
However, evidence supports an
approach that assesses dominance
by introducing plus in front of
each eye separately, under binocular conditions, then determining which disturbs distance vision
more significantly (Robboy et
al,1990; Collins and Goode,1994;
Handa et al, 2005). The dominant
eye is the one more bothered by
the plus in front of it. Place the
near biased multifocal contact
lens on the other, more “tolerant,”
non-dominant eye.
Adaptability
We all recognize that some patients are more visually sensitive
than others. Those with a more
adaptable visual system tend to
(Continued on page 56)
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
11
GP Insights
B
Y
E
D
W
A
R
D
S
.
B
E
N
N
E
T
T
,
O
D
,
M
S
E
D
,
F
A
A
O
Using Peroxide With GP Lenses
H
ydrogen peroxide disinfection offers benefits over
other care systems. It consists of a 3% hydrogen
peroxide solution, typically accompanied by a
neutralizing tablet or disc. It has been found to be
safe, effective and preservativefree (Henry and Do, 2014). It
produces a free radical superoxide
that is toxic to microbes (Ward,
2013). And, whereas other systems
often demonstrate incomplete
effectiveness against Acanthamoeba, hydrogen peroxide has been
shown to be effective against
both the trophozoite (Hughes &
Kilvington, 2001) and cyst (Mowrey-McKee & George, 2007)
forms of Acanthamoeba. It is also
an effective cleaner due to its low
ionic composition and hypotonic
nature. It has the ability to lyse
proteins and lipids from the lens
surface while also penetrating microbial biofilms (Gromacki, 2012).
Because the active disinfectant
ingredient is hydrogen peroxide
and not a preservative, it is a good
system for both dry eye patients
and those who are hypersensitive.
All of these attributes also would
be beneficial for individuals who
aren’t particularly compliant with
lens care.
Hydrogen Peroxide and GPs?
However, do these benefits make
hydrogen peroxide systems effective for rigid gas permeable (GP)
lenses? The answer is yes. Peroxide’s ability to act as a disinfectant
and remove protein buildup on
GP lenses is advantageous
(Gromacki and Ward, 2013). Be12
■
cause GP lenses don’t absorb a
significant amount of the storage
solution, patients can safely rinse
this solution from the surface
with a morning saline rinse prior
to insertion.
Hydrogen peroxide is one of
the preferred modalities in 48%
of respondents to a scleral lens
solution survey by Eef van der
Worp for his I-Site newsletter
(2010) and was the preferred modality in 23% of respondents in a
CL Today Quick Poll on scleral
lens care (Nichols and Gromacki,
2013).
Peroxide Systems Available
Presently there are two hydrogen peroxide systems cleared by
the FDA for use with GP lenses:
PeroxiClear from Bausch + Lomb
and Clear Care Cleaning &
Disinfecting Solution from Alcon.
Both are one-step systems.
In March 2014, Bausch +
Lomb introduced the PeroxiClear hydrogen peroxide system
indicated for use with all lenses,
including GP lenses. This solution
is a unique formula that contains
Triple-Moist Technology, which
claims to provide up to 20 hours
of moisture according to Bausch +
Lomb. PeroxiClear has a shorter
neutralization cycle (4 hours)
than Clear Care. The Clear Care
peroxide system requires a 6-hour
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
soak. It contains Pluronic 17R4 as
a cleaning agent.
Both systems contain a platinum disc attached to the lens case
that will initiate the neutralization of hydrogen peroxide process
immediately after insertion of the
lens into the case, but the neutralization occurs at different rates
for each solution.
B+L recommends that users
discard the bottle and lens case
90 days after opening or after
35 uses, whichever comes first.
Clear Care packaging recommends users dispose of the old
case with each new purchase of
Clear Care.
Regardless of the system used,
a digital cleaning step is recommended by both manufacturers
prior to disinfection.
Peroxide Works With GP Lenses
The traditional use of hydrogen
peroxide disinfection for GP
wearers who have dry eye or preservative sensitivity is likely to
increase as a result of both a new
system indicated for GP lenses as
well as the increasing popularity
of scleral lens designs. With the
benefits of effective lens disinfection and cleanliness, hydrogen
peroxide should be considered a
viable — if not preferred — lens
care option for your new and
existing GP wearers. CLS
For references, please visit www.
clspectrum.com/references.asp and
click on document #SE2014.
Dr. Bennett is assistant dean for Student Services and Alumni Relations at the University of
Missouri-St. Louis College of Optometry and is
executive director of the GP Lens Institute. You
can reach him at [email protected].
w w w. c l s p e c t r u m . c o m
Contact Lens Design & Materials
B
Y
N
E
I
L
P
E
N
C
E
,
O
D
,
F
A
A
O
Characteristics of a New
Silicone Hydrogel Contact Lens
I
n the past few years, new silicone hydrogel contact lens introductions have been limited to the daily disposable category. In fact, it
has been several years since a new monthly or
semi-monthly silicone hydrogel
product had appeared, until the
spring 2014 launch of the new
Bausch + Lomb Ultra contact lens
with MoistureSeal technology.
Bausch + Lomb Ultra contact
lenses have several unique material innovations. Compared to
hydrogel lenses, silicone hydrogel
contact lenses are significant because of the oxygen permeable
characteristics of silicone. To
achieve the goal of increased oxygen transmission and the related
health benefits for the cornea that
silicone allows, other less desirable characteristics of silicone
must be accounted for. Silicone is
a stiffer, higher modulus material
with very poor wetting characteristics. The lens design team
is challenged to overcome these
negative attributes in an attempt
to achieve an ultimate balance of
health, wettability, comfort, vision, and handling.
One of the unique aspects of
the Bausch + Lomb Ultra (samfilcon A) material involves the
make-up of the silicone component. Rather than having a single
silicone material incorporated
into the silicone hydrogel product, Bausch + Lomb Ultra utilizes
a combination of three distinct
w w w. c l s p e c t r u m . c o m
types of silicone. The lens takes
advantage of slightly different
attributes of the three silicone
materials. By finding the optimal
mix of three different silicones,
the material is able to provide a
balance of high oxygen transmissibility and low modulus.
The second significant innovation related to Bausch + Lomb
Ultra contact lenses involves
the polymerization process. In a
unique two-phase curing process,
the silicone components polymerize first in the mold when subjected to specific radiant energy.
This forms a basic structure or
framework for the eventual silicone hydrogel contact lens.
In a time-delayed second
phase, polyvinylpyrrolidone
(PVP) is then polymerized
through and around this silicone
lattice-like framework. The lens
designers tell us that this allowed
significantly more PVP to be
incorporated into the silicone
hydrogel, which should result
in enhanced moisture retention
characteristics for the material.
The final result of the material and manufacturing science
efforts is a 46% water content
silicone hydrogel lens with one
of the lowest modulus values in
the monthly silicone hydrogel
category. The Dk/t is 163 at the
center of a -3.00 diopter lens,
which has a center thickness of
0.07 mm. The lens is produced
with a 14.2 mm diameter, and has
an 8.5 mm base curve. The edge
design shows a tapered, relatively
thin profile.
The Bausch + Lomb Ultra
contact lens employs aspheric
optics designed to correct the average spherical aberration of the
eye, similar to other lenses made
by the company.
Bausch + Lomb has introduced
the lens as a monthly replacement
contact lens. Currently, the FDA
has granted clearance to
Bausch + Lomb Ultra for daily
wear. Power availability will be
from +6.00 to –12.00 D, in 0.25D
steps for most of that range, but
0.50D steps above –6.00D.
The result of polymer
chemistry, manufacturing and
lens design innovations, the
Bausch + Lomb Ultra silicone
hydrogel monthly replacement
contact lens should be a welcome
addition to the contact lens market. Achieving the desired balance
of health, vision, comfort and
handling attributes is not only the
goal of contact lens manufactures,
but of the practicing contact lens
fitter as well. CLS
Dr. Pence serves as associate dean, Clinical
and Patient Services, Indiana University School
of Optometry in Bloomington, Ind. He is a consultant or advisor to B+L, Alcon, and Vistakon
and has received research funding from AMO.
You can reach him at [email protected].
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
13
Dry Eye Dx and Tx
B
Y
K
A T
H
E
R
I
N
E
M
.
M
A
S
T
R
O
T A
,
M
S
,
O
D ,
F A
A O
Ocular Surface and Tear Film in
Contact Lens Discomfort
I
n the fall of 2013, the Tear Film and Ocular
Surface (TFOS) Society published The TFOS
International Workshop on Contact Lens Discomfort (CLD) report (Nichols et al, 2013). This
international consensus follows
two prior workshops, the Dry
Eye Workshop (DEWS) and the
Meibomian Gland Dysfunction
(MGD) Workshop.
These workshops constructed
an evidence-based approach for
evaluating their target subjects.
And, equally important, they
proposed direction for continued
information and data gathering in
areas showing promise for identifying the elusive mechanisms core
to clinical dysfunctions.
Questions Answered
The CLD Workshop was charged
with addressing the following
concerns: Why do contact lens
wearers develop discomfort? How
is CLD defined? How can we
classify it? Who gets CLD? How
does CLD happen? How do we
manage CLD? How do contact
lens materials, designs, and care
impact CLD? How do we design
clinical trials to answer these
questions?
Subcommittees of the CLD
Workshop investigated how, or
if, contact lens interactions with
the ocular surface and tear film
contributed to lens-wearing discomfort, or rather “adverse ocular
sensation”—that is, dryness, irri14
■
tation, discomfort, fatigue, and so
on — during lens wear.
Findings
Interestingly, in an evidencebased review, there was no significant association with morphologic changes in the corneal epithe-
Does contact lens
wear cause dry eye
or does dry eye
cause contact lens
discomfort?
lium (barrier function, staining)
or corneal hypoxia with CLD. Of
note, the conjunctiva, both bulbar
and marginal (the leading edge
of the palpebral conjunctiva as it
moves across the contact lens surface, or “lid-wiper”) proved to be
a tissue more closely linked to the
development of CLD.
Additionally, contact lens
wear does appear to affect the
morphology and function of the
meibomian glands. Furthermore,
the frequency of meibomian loss
is higher in contact lens wearers
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
compared with non-lens wearers.
Thus, contact lens wear may result in MGD.
Tear film changes occur with
the introduction of a contact lens
to the ocular surface. Consider
that the presence of a contact lens
on the eye divides the tear film
into a pre- and postlens tear film,
creating new ocular interfaces
within the ocular environment.
The direct biophysical impact of
the resultant decreased tear film
stability, increased tear evaporation rate, reduced tear film turnover and tear ferning are associated with CLD. (Tear ferning is the
branching crystallization pattern
of tear fluid once collected and
dropped on a microscopy slide
and allowed to dry; ferning is an
indication of tear functionality).
Does contact lens wear cause
dry eye or does dry eye cause
contact lens discomfort? There
is much to discover about the
dynamic interplay of the ocular
surface and a contact lens. The
CLD Workshop report is a compendium of what we know and a
guide to follow as we search for
more answers in CLD and ocular
surface disease. CLS
For references, please visit www.
clspectrum.com/references.asp and
click on document #SE2014.
Dr. Mastrota is secretary of the Ocular Surface
Society of Optometry and center director at
the New York office of Omni Eye Services. She
is a stock shareholder of TearLab Corporation
and a consultant or advisor to Alcon, Allergan,
B+L, Nicox, OcuSoft and Sarcode Bioscience.
Contact her at [email protected].
w w w. c l s p e c t r u m . c o m
Contact Lens Care & Compliance
B
Y
M
I
C
H
A
E
L
A
.
W
A
R
D
,
M
M
S
C
,
F
A
A
O
New Option for Peroxide
Disinfection
P
eroxiClear is a new entrant to our peroxidebased contact lens disinfectant armamentarium.
It’s a one-step 3% hydrogen peroxide (H2O2)-
based cleaning and disinfecting system, which
claims to keep lenses cleaner and
moister for longer periods with
complete disinfection and neutralization in a 4-hour time frame.
Chemistry
PeroxiClear contains Bausch +
Lomb’s Triple-Moist technology,
which employs three moisturizing ingredients: poloxamer 181,
propylene glycol and carbamide.
Poloxamer 181 is unique to this
product. It’s a surfactant that persists on lens surfaces and helps to
attract and spread moisture over
the surface of the contact lens.
Propylene glycol (PG) is a
surfactant, wetting agent and dispersant and is a common component in artificial tears. PG mixes
completely with water and can
hold approximately 2.8 times its
weight in water (Bausch + Lomb,
Patent EP0969812A1, 2000).
Carbamide functions as both
a moisturizing agent and a platinum-modulating agent (PMC)
(Millard et al, 2014). As a PMC, it
reversibly binds to the platinum
on the neutralizing disc, slowing
the initial rate of neutralization of
hydrogen peroxide.
This process allows a higher
concentration of peroxide over a
longer time frame, which effecw w w. c l s p e c t r u m . c o m
tively strengthens the antimicrobial activity of the system.
The platinum disc catalyzes
the breakdown of H2O2 into
oxygen and water. As this reaction proceeds the dynamics of
the solution shift, allowing the
carbamide to return to solution
and lens surface, increasing availability of peroxide molecules to
interact with platinum disc neutralizing sites.
PeroxiClear has a disinfection
and neutralization time of
4 hours. This 3% H2O2/platinum
disc neutralization system claims
99.9% disinfection efficacy, which
is consistent with other one step
peroxide-based systems. PeroxiClear is preservative free.
Peroxide Disinfectants
Hydrogen peroxide disinfecting
systems offer antimicrobial efficacy without the use of preservatives. Microfiltered, stabilized and
buffered 3% hydrogen peroxide
is the disinfectant in peroxidebased systems, which are effective
against a wide variety of organisms, such as bacteria, fungi (including spores and yeasts), viruses
and some protozoa.
Hydrogen peroxide destroys
pathogens by oxidation, creat-
ing the free radical superoxide,
which is toxic to DNA. Peroxides
denature proteins, thus damaging
necessary microbial cell structures
(Ward, 2006).
The hydrogen peroxide in
these systems must be neutralized
prior to lens wear because unneutralized peroxide is toxic. A concern with any hydrogen peroxide
disinfection product is the potential for contamination of lenses
stored in previously neutralized
peroxide solution. Although hydrogen peroxide systems have
high antimicrobial efficacies at
full strength, once neutralized,
they become unpreserved aqueous bathing solutions, capable of
supporting microbial growth.
That said, peroxide systems
work fine if used on a daily basis,
They are approved for 7 days
of storage, but patients should
pay attention to the inside of the
lens case cap as little or no disinfection occurs on this surface.
Patients can disinfect the cap by
rinsing it with fresh peroxide.
Remember to instruct patients
to always follow the instructions
of each individual care system.
CLS
For references, please visit www.
clspectrum.com/references and click
on document #SE2014.
Mr. Ward is an instructor in ophthalmology
at Emory University School of Medicine and
Director, Emory Contact Lens Service. He is a
consultant/advisor to Alcon and B+L. You can
reach him at [email protected].
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
15
Exceptional Lens Care Solutions from
Exceed any of your patients’ needs
Multi-purpose
Peroxide
9 OUT OF 10
Prefer Biotrue
over the leading
multi-purpose solution1
®
Rigid gas permeable
The most advanced* #1 doctor recommended
peroxide
RGP brand*
* Compared to Clear Care
*Symphony Health Solutions, data on file.
Biotrue® Multi-Purpose Solution
• Works like your eyes with the same pH and
lubricant they have naturally
• Provides up to 20 hours of moisture2
• Kills 99.9% of germs3
www.biotrue.com
PeroxiClear™ 3% Hydrogen Peroxide
Cleaning and Disinfecting Solution
• Provides superior all-day comfort4-5*
• Keeps lenses cleaner** and moister for longer4-7*
• Delivers exceptional disinfection in only 4 hours
*Compared to Clear Care
**Using ACUVUE ADVANCE and ACUVUE OASYS lenses
www.bausch.com/peroxiclear
Boston® Solution System
• Excellent disinfection in a mild, gentle formula
Boston SIMPLUS® Multi-Action Solution
• Cleans, disinfects, conditions, and removes protein with
single-bottle convenience
Boston ADVANCE® Comfort Formula System
• Enhanced wettability for exceptional comfort
www.bausch.com/boston
REFERENCES: 1. A total of 300 eye care practitioners asked patients to use Biotrue. 811 self-identified OPTI-FREE RepleniSH users used Biotrue for at least 3 days and responded to an onlinesurvey. 2. Results of U.S. in vitro study performed to evaluate
the rate of release of wetting agents from various silicone hydrogel lens materials over a period of 20 hours. 3. Results of in vitro study following FDA/ISO stand†alone procedure for disinfecting products modified with organic soil added to create a more
rigorous test condition. Primary criteria for effective disinfection are defined as a reduction in the number of bacteria by a minimum of 3 logs (99.9%) and a reduction of mold and yeast by a minimum of 1 log (90%) within the recommended disinfection time.
4. Results from a 22-investigator, multi-site study of PeroxiClear™, with a total of 440 eligible subjects. Subjects were randomized to use either PeroxiClear™ or Clear Care for 3 months. Subjects completed performance surveys at 2-week, 1-month, 2-month,
and 3-month visits. 5. Results from a 21-investigator, multi-site study of PeroxiClear™, with a total of 297 eligible subjects who were habitual Clear Care users. After 7 days of use, subjects completed an online survey. Consumers rated the performance of
PeroxiClear™ across a range of attributes and compared the performance to their habitual Clear Care solution. 6. High-resolution/accurate-mass (HR/AM) mass spectrometry was used to detect and quantitate the relative amounts of surfactant retained
on lenses from PeroxiClear™ and Clear Care solutions after 20 hours of wear. PureVision®2, ACUVUE OASYS, and AIR OPTIX AQUA lenses were soaked in solutions for 12 hours prior to patients wearing lenses for 20 hours. 7. Results of an ex vivo study
measuring deposits on worn contact lenses to compare the clinical performance of PeroxiClear™ and Clear Care solutions. Lenses were worn daily for 1 month (silicone hydrogel and Group IV hydrogel lenses) or 3 months (gas permeable lenses). A total of
374 lenses were randomly selected for image analysis. Lenses were scored for mean density of deposits and percent coverage of deposits.
Distributed by Bausch + Lomb, a Division of Valeant Pharmaceuticals North America LLC, Bridgewater, N.J. © 2014 Bausch & Lomb Incorporated. ®/™ are trademarks of Bausch & Lomb Incorporated or its affiliates. All other brand/product names are
trademarks of their respective owners. PNS07302 US/BIO/14/0020
CONTAC T LENS DISCOMFORT
Contact Lens
Discomfort Defined
Each year, patients in our practices are struggling with
lens wear, and in some cases, dropping silently out of lens
wear. How do we get to the bottom of this problem?
By Katherine M. Bickle, OD, MS and Kelly K . Nichols, OD, MPH, PhD
C
Dr. Bickle is a Ph.D. student
at The Ohio State University
College of Optometry and
is in private practice in
Granville, OH. She is a consultant to Bausch + Lomb.
Dr. Nichols is Dean and
Professor of the University
of Alabama at Birmingham.
In the past 12 months, she
has been a consultant to
Alcon, Allergan,
Bausch + Lomb/Valeant,
Insite, Kala and Nicox.
She has received research
support from Allergan and
Sarode/Shire and has stock
options in TearLab.
18
■
ontact lens discomfort
(CLD) is a frequently
reported symptom of
patients wearing contact lenses and a primary reason for contact lens “drop out”
(Dumbleton et al, 2013; Richdale et
al 2007; Young et al 2002). Reported
rates of contact lens “drop out” range
between 23-34% (Dumbleton et al,
2013; Richdale et al, 2007; Pritchard
et al, 1999). To summarize, half of
your contact lens patients experience
frequent discomfort, and on average,
one of every four drop out of lens
wear entirely, which can significantly
impact your practice bottom line. We
practitioners who fit contact lenses
may consider changing the patient’s
lens material, replacement schedule,
wearing time, lens care solution, adding additional therapy, or a combination of the above as possible treatment
options to appropriately address the
patient’s needs. However, there is a
lack of literature detailing the classification, definition, and etiology, which
are needed for the appropriate treatment and management of CLD. Thus,
the Tear Film and Ocular Surface
Society (TFOS) conducted an Inter-
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
national Workshop on Contact Lens
Discomfort to address topics related
to CLD and provide an appropriate
foundation for further research, diagnosis, treatment, and management of
CLD with an ultimate goal of keeping
patients successful contact lens wearers. The Executive Summary along
with the entire report can be found in
the October 2013 issue of Investigative
Ophthalmology & Visual Science (IOVS)
(Nichols et al, 2013).
Defining Contact Lens
Discomfort
To provide a detailed description of
the condition that can also be utilized
for future work, the TFOS Workshop
developed the following definition for
CLD:
“Contact lens discomfort is a condition characterized by episodic or
persistent adverse ocular sensations
related to lens wear, either with or
without visual disturbance, resulting
from reduced compatibility between
the contact lens and the ocular environment, which can lead to decreased
wearing time and discontinuation
of contact lens wear” (Nichols et al,
2013).
w w w. c l s p e c t r u m . c o m
The Defintion and Classification Report classified CLD into two main categories, discomfort related to the “contact lens” and/or the “environment”
(Nichols et al, 2013). The contact lens category is
further separated into 4 subgroups, “contact lens material, contact lens design, contact lens fit and wear,
and lens care,” while the four subgroups of environment are “inherent patient factors, modifiable patient
factors, ocular environment, and external environment.” While some of these factors have been more
thoroughly investigated or validated than others, it
is necessary to develop an understanding of the role
each of these factors has on CLD with future studies.
Previous studies evaluating contact lenses that differ
by only one factor, such as water content, have been
lacking in the literature, in part due to the difficulty
in separating material factors. Patient factors and
environmental factors have been studied to some
degree, although not in a systematic way. There is
much work to be done.
By definition, CLD symptoms diminish or cease
after contact lens removal. Thus, this workshop summary was not focused on underlying dry eye in contact lens wearers. Reported symptoms from patients
with contact lens dry eye may be similar to CLD, but
these symptoms are present with and without contact
lens wear, thus the terminology should not be used
interchangeably.
A patient’s progression with CLD is also outlined
within the report. First, an initial awareness of symptoms and difficulty with lens wear (“strugglers”) can
progress to reduced comfortable and total wear time,
which can ultimately result in discontinuing contact
lens wear permanently. Consider where your contact
lens patients fall on this scale and how you can utilize your clinical expertise and the evidence-based
approach of the CLD workshop to prevent them
from dropping out of contact lens wear through early
identification and appropriate management. The goal
of successful contact lens wear should be paramount
in today’s clinical practice.
Identifying Patients With
Contact Lens Discomfort
While CLD symptoms can vary, patients will typically report some type of dryness, irritation, fluctuation in vision, discomfort, or foreign body sensation
after contact lens insertion, and these symptoms may
increase in frequency and severity throughout the
wear time. This cycle typically continues every day.
Obtaining a thorough history from the patient is crucial with appropriate questions or factors to consider
w w w. c l s p e c t r u m . c o m
including the patient’s age, gender, medical history,
and medications, onset and frequency of symptoms,
previous and current lens material and care system(s).
Important questions to determine where a patient
is in the progression toward discomfort include total wearing time and comfortable wearing time. Are
both of these enough for the patient? If a patient has
Patients will typically
report some type of
dryness, irritation,
fluctuation in vision,
discomfort, or foreign
body sensation after
contact lens insertion.
This cycle typically
continues every day.
tried every care system and many different lenses, he
is at much higher risk of discontinuing contact lens
wear. Lens replacement schedule, usage of topical eye
drops or other therapies, compliance, and environmental concerns also can provide direction in crafting an appropriate management plan.
Even if a patient is symptomatic, there may be
a lack of signs to correlate with these symptoms.
Therefore, when treating and managing these patients, relying on the patient’s symptoms is important as this can be the driving force for the patient
ultimately choosing to continue with contact lens
wear. Questionnaires such as the Contact Lens Dry
Eye Questionnaire (Nichols et al, 2002), the Ocular
Surface Disease Index (Schiffman et al, 2000), or the
Standard Patient Evaluation of Eye Dryness survey
(Ngo et al, 2013) may be useful tools to incorporate
into your practice. Staff members can administer and
grade these questionnaires to assist you in identifying
or monitoring patients who may be at risk for CLD.
Contact Lens Materials, Design and Care
There are many factors that we as practitioners consider when choosing an appropriate lens material, assessing the lens fit, and choosing a suitable lens care
solution for our patients. Based upon current knowledge and studies reported in the literature, it is dif-
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
19
CONTAC T LENS DISCOMFORT
ficult to determine the true role that contact lens materials and design (lubricity, surface treatments, water
content, modulus, Dk/t, and so on) and lens care have
on contact lens discomfort (Santodomingo-Rubido
et al, 2006, Fonn and Dumbleton, 2003). This is not
necessarily due to their lack of association with CLD
but as a result of varying definitions, study designs,
and the difficulty in changing and evaluating only
one factor related to the lens design/material in typical research or clinical settings (Jones et al, 2013).
Only a manufacturer has the ability to control for individual factors within a given material to assess the
impact on CLD.
It is not surprising given this lack of ability to
control factors independently that most factors men-
lens discomfort. However, the lens edge design can
impact a patient’s level of comfort and result in clinical signs. Further discussion on this later.
Although there is no true agreement on the optimal composition of a lens care solution in terms of
improving comfort, patient education remains crucial. Patients must be instructed not only how to most
effectively use their solution but also proper contact
lens wearing and replacement schedules. Revisiting
this issue with staff who routinely train patients can
promote compliance.
Impact on the Ocular Surface and Adnexa
While some corneal (hypoxia, stromal infiltrates,
neovascularization, endothelial changes), conjuncti-
The true role of lens deposition and its impact on
contact lens discomfort remain unknown, but this
should not discourage practitioners from changing
lenses, care solutions, or other therapies if lens
deposition is resulting in other issues for the patient.
tioned above have shown no strong association with
CLD in the literature. However, there is some recent
preliminary support for lubricity being an important factor in CLD (Jones et al, 2013). Theoretically,
a lens with a lower coefficient of friction provides a
smoother interaction between the lens and the eyelid.
Considering the number of times we blink each day,
reducing friction makes sense clinically. It remains to
be seen whether clinical findings such as lid wiper epitheliopathy, thought to be associated with mechanical friction, are reduced or eliminated with newer
lens materials that offer lower coefficients of friction.
The true role of lens deposition and its impact on
contact lens discomfort remain unknown, but this
should not discourage practitioners from changing
lenses, care solutions, or other therapies if lens deposition is resulting in other issues for the patient. Underlying dry eye or meibomian gland dysfunction are
also considerations, and may impact the lens material
selected for a patient as materials and coatings create
differential deposition on lenses. While this may not
directly correlate with CLD, it’s worth consideration.
Additionally, lens fits are assessed for corneal coverage, centration, and movement, but there is no true
consensus on the impact of these factors on contact
20
■
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
val (bulbar hyperemia), or limbal (limbal hyperemia)
changes may lead to changes in your treatment and
management of the patient, there have been no direct
associations between these factors and contact lens
discomfort (Efron et al, 2013). However, there appears to be a stronger link with the bulbar conjunctival staining and “lid wiper” changes assessed with
lissamine green (Guillon and Maissa, 2005; Korb et
al, 2002; Yeniad et al, 2010). Although sodium fluorescein instillation may be more commonly used
in clinical practice to assess corneal staining, tear
break up time, etc., the use of lissamine green can
provide valuable information related to the severity
and pattern of conjunctival staining. Additionally, as
reported in the literature, changes to the “lid wiper”
area have also been related to CLD (Korb et al, 2002;
Yeniad et al, 2010). However, debate exists on the
exact etiology of lid wiper epitheliopathy (LWE),
whether lens or other therapy changes impact LWE,
and what impact these modifications will have on a
patient’s symptoms.
Examination of the meibomian glands is also important. While meibomian glands are frequently associated with dry eye, there is evidence that contact
lens wear can potentially negatively affect the func-
w w w. c l s p e c t r u m . c o m
CONTAC T LENS DISCOMFORT
tion of the meibomian glands. Arita and coworkers
have used infrared meibography to associate gland
loss with years of lens wear (Arita et al, 2009). These
studies will be useful in determining which comes
first in this chicken-and-egg argument.
In summary, the meibomian glands and LWE have
been shown in the literature to have a stronger connection to CLD than other areas of the ocular surface
and adnexa (Henriquez and Korb, 1981; Korb et al,
2002). Lissamine green testing is quick and provides
little to no discomfort to the patient while potentially
providing valuable information as you’re managing
a patient with contact lens discomfort. Further research investigating the association between CLD
and the meibomian glands or LWE to better understand their role in CLD is worthwhile and needed.
Contact Lens Wear and the Tear Film
A pre-and post-lens tear film is created after the application of a contact lens. This disruption of the tear
film has been shown to negatively impact the evaporation rate and stability of the tear film, and these factors have been associated with CLD (Fonn et al, 1999;
Glasson et al 1999; Kojima et al, 2011). Despite these
changes to the tear film that occur with contact lens
insertion, there are successful contact lenses wearers,
and thus, it is important to consider that there are
multiple factors on the ocular surface that contribute
to these changes and the patient’s symptoms, as well
as factors that determine success (Craig et al, 2013).
In the future, we believe we will continue to see lens
materials and care systems designed to have minimal
impact on the normal tear film and even help prevent
lens material dehydration. This may result in better
stability of the tear film with lens wear, which will
provide practitioners with additional options to reduce CLD symptoms in patients while also providing
better and more stable vision.
Treating and Managing Your
Patients with CLD
Although a contact lens patient may report symptoms of discomfort, we must also consider that there
are other potential non-contact lens-related factors
or etiologies of this discomfort. It is important to appropriately treat and manage these factors, which can
help you determine whether the discomfort is truly
contact lens-related (Papas et al, 2013).
The CLD report reviewed the existing literature
surrounding management of discomfort with contact lens wear. While the terminology used in defining subjects for the multitude of studies varied, some
w w w. c l s p e c t r u m . c o m
common themes emerged (Papas et al, 2013). After
treating any other underlying conditions, switching
the contact lens material may be chosen as a treatment
option. In a rigid lens patient, consider changing to
a lens with a steeper base curve in a soft lens patient
and using a larger diameter lens as this may provide
some relief of symptoms. Additionally, switching to a
The meibomian glands and
lid wiper epitheliopathy
have been shown in
the literature to have a
stronger connection to
CLD than other areas
of the ocular surface
and adnexa.
daily disposable contact lens may provide some improvement in CLD. (Solomon et al, 1996; Cho and
Boost, 2013).
While there are some therapies that have been utilized in treatment of dry eye such as artificial tears,
fish oil, topical medications, such as cyclosporine A
(Kim et al, 2009; Rao, 2010), topical azithromycin
(Opitz DL and Tyler KF, 2011; Luchs 2008), and steroids (Pflugfelder et al, 2004), punctal plugs (Ervin et
al, 2010), and avoiding certain environments, such as
low humidity, and so on (Gonzalez-Garcia MJ, 2007),
further research is needed to determine the benefits
of these treatments with CLD.
Conclusion
While we still have much to learn about CLD, we
now have a definition and classification scheme that
provides a foundation on which future research can
be focused to help us better understand this condition through the CLD reports (Nichols et al, 2013).
Practitioners, researchers, and companies are constantly striving to develop and provide new contact
lens materials, lens care solutions, and other treatment options for our patients to reduce or even better prevent symptoms associated with contact lens
discomfort. These efforts will ultimately result in
more of our patients being successful contact lens
wearers. CLS
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
21
CONTAC T LENS DISCOMFORT
References
1. Dumbleton K, Wood CA, Jones LW, Fonn D. The impact of
contemporary contact lenses on contact lens discontinuation.
Eye Contact Lens. 2013; 39(1): 93-99.
17. Yeniad B, Beginoglu M, Bilgin LK. Lid-wiper epitheliopathy
in contact lens users and patients with dry eye. Eye Contact
Lens. 2010;36(3):140-143.
2. Richdale K, Sinnott LT, Skadahl E, Nichols JJ. Frequency of
and factors associated with contact lens dissatisfaction and
discontinuation. Cornea. 2007; 26(2): 168-174.
18. Arita R, Itoh K, Inoue K, Kuchiba A, Yamaguchi T, Amano S.
Contact lens wear is associated with decrease of meibomian
glands. Ophthalmology. 2009; 116(30):379-384.
3. Young G, Veys J, Pritchard N, Coleman S. A multi-centre
study of lapsed contact lens wearers. Ophthalmic Physiol Opt.
2002; 22(6): 516-527.
19. Henriquez AS, Korb DR. Meibomian glands and contact lens
wear. Br J Ophthalmol. 1981;65(2)108-111.
4. Pritchard N, Fonn D, Brazeau D. Discontinuation of contact
lens wear: a survey. Int Contact Lens Clin. 1999; 26(6): 157162.
5. Nichols JJ, Willcox MDP, Bron AJ, et al. The TFOS International Workshop on Contact Lens Discomfort: Executive
Summary. Invest Ophthalmol Vis Sci. 2013; 54(11): TFOS713.
6. Nichols KK, Redfern RL, Jacob JT, et al. The TFOS International Workshop on Contact Lens Discomfort Report of the
Definition and Classification Subcommittee. Invest Ophthalmol Vis Sci. 2013; 54(11): TFOS14-19.
7. Nichols JJ, Mitchell GL, Nichols KK, Chalmers R, Begley C.
The performance of the contact lens dry eye questionnaire as
a screening survey for contact lens-related dry eye. Cornea.
2002; 21(5): 469-75.
8. Schiffman RM, Christianson MD, Jacobsen G, Hirsch JD,
Reis BL. Reliability and validity of the Ocular Surface Disease
Index. Arch Ophthalmol. 2000; 118(5): 615-21.
9. Ngo W, Situ P, Keir N, Korb D, Blackie C, Simpson T. Psychometric properties and validation of the Standard Patient
Evaluation of Eye Dryness questionnaire. Cornea. 2013; 32(9):
1204-1210.
10. Santodomingo-Rubido J, Wolffsohn JS, Gilmartin B.
Changes in ocular physiology, tear film characteristics, and
symptomatology with 18 months silicone hydrogel lens wear.
Optom Vis Sci. 2006; 83(20): 73-81.
11. Fonn D, Dumbleton K. Dryness and discomfort with silicone
hydrogel contact lenses. Eye Contact Lens. 2003; 29(suppl 1):
S101-S104; discussion S115-S118, S192-194.
12. Jones L, Brennan NA, Gonzáles-Méijome J, et al. The TFOS
International Workshop on Contact Lens Discomfort:
Report of the Contact Lens Materials, Design, and Care
Subcommittee. Invest Ophthalmol Vis Sci. 2013; 54(11):
TFOS37-TFOS70.
13. Efron N, Jones L, Bron AJ, et al. The TFOS International
Workshop on Contact Lens Discomfort: Report of the
Contact Lens Interactions With the Ocular Surface and
Adnexa Subcommittee. Invest Ophthalmol Vis Sci. 2013; 54:
TFOS98-TFOS122.
14. Guillon M, Maissa C. Bulbar conjunctival staining in contact
lens wearers and non lens wearers and its association with
symptomatology. Cont Lens Anterior Eye. 2005; 28(2): 6773.
15. Korb DR, Greiner JV, Herman JP, et al. Lid-wiper epitheliopathy and dry-eye symptoms in contact lens wearers. CLAO
J. 2002; 28(4): 211-216.
16. Craig JP, Willcox MDP, Argüeso P, et al. The TFOS International Workshop on Contact Lens Discomfort: Report of the
Contact Lens Interactions With the Tear Film Subcommittee. Invest Ophthalmol Vis Sci. 2013; 54(11): TFOS123-156.
22
■
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
20. Fonn D, Situ P, Simpson T. Hydrogel lens dehydration and
subjective comfort and dryness ratings in symptomatic and
asymptomatic contact lens wearers. Optom Vis Sci. 1999;
76(10): 700-704.
21. Glasson MJ, Hseuh S, Willcox MD. Preliminary tear film
measurements of tolerant and non-tolerant contact lens
wearers. Clin Exp Optom. 1999; 82(5): 177-181.
22. Kojima T, Matsumoto Y, Ibrahim OM, et al. Effect of
controlled adverse chamber environment exposure ton tear
functions in silicon hydrogel and hydrogel soft contact lens
wearers. Invest Ophthalmol Vis Sci. 2011; 52(12): 8811-8817.
23. Papas EB, Ciolino JB, Jacbos D, et al. The TFOS International Workshop on Contact Lens Discomfort: Report of the
Management and Therapy Subcommittee. Invest Ophthalmol
Vis Sci. 2013; 54(11): TFOS183-TFOS203.
24. Solomon OD, Freeman MI, Boshnick EL, et al. A 3-year
prospective study of the clinical performance of daily disposable contact lenses compared with frequent replacement and
conventional daily wear contact lenses. CLAO. 1996; 22(4):
250-257.
25. Cho, P, Boost MV. Daily disposable lenses: The better alternative. Cont Lens Anterior Eye. 2013; 36(1): 4-12.
26. Kim EC, Choi JS, Joo CK. A comparison of vitamin a and
cyclosporine a 0.05% eye drops for treatment of dry eye
syndrome. Am J Ophthalmol. 2009; 147(2): 206-213.
27. Rao SN. Topical cyclosporine 0.05% for the prevention of
dry eye disease progression. J Ocul Pharmacol Ther. 2010;
26(2): 157-164.
28. Opitz DL, Tyler KF. Efficacy of azithromycin 1% ophthalmic
solution for treatment of ocular surface disease from posterior blepharitis. Clin Exp Optom. 2011; 94(2): 200-206.
29. Luchs J. Efficacy of topical azithromycin ophthalmic solution
1% in the treatment of posterior blepharitis. Adv Ther. 2008;
25(9): 858-870.
30. Pflugfelder SC, Maskin SL, Anderson B, et al. A randomized,
double-masked, placebo-controlled, multicenter comparison
of loteprednol etabonate ophthalmic suspension, 0.5%, and
placebo for treatment of keratoconjunctivitis sicca in patients
with delayed tear clearance. Am J Ophthalmol. 2004; 138(3):
444-457.
31. Ervin AM, Wojciechowski R, Schein O. Punctal occlusion
for dry eye syndrome. Cochrane Database Syst Rev. 2010; 9:
CD006775.
32. Gonzalez-Garcia MJ, Gonzalez-Saiz A, De la Fuente B, et al.
Exposure to a controlled adverse environment impairs the
ocular surface of subjects with minimally symptomatic dry
eye. Invest Ophthalmol Vis Sci. 2007; 48(9): 4026-4032.
US/ZUS/14/0135
w w w. c l s p e c t r u m . c o m
NEW CONTAC T LENS
Breaking the Cycle
of Discomfort
Advanced contact lens materials and manufacturing process deliver exceptional comfort.
Dr. Wygladacz is a Senior
Research Scientist in Vision
Care R&D at Bausch + Lomb,
a division of Valeant Pharmaceuticals International.
Dr. Hook is a Senior Principal
Scientist at Valeant Pharmaceuticals International, Inc.
and Group Leader of the
Structural and Surface
Science Group within
Bausch + Lomb.
Dr. Steffen is the director
of Clinical Affairs at
Bausch + Lomb, a division
of Valeant Pharmaceuticals.
Dr. Reindel is the Medical
Director for Bausch + Lomb
Canada.
w w w. c l s p e c t r u m . c o m
B y Kat a r z y n a W yg l a d a c z , M S , P h D ; D a n i e l H o o k , B S , M S , P h D ;
R o b e r t St e f f e n , O D, M S & W illi a m R e i n d e l , O D, M S
D
uring thousands of
blinks each day, a contact lens wearer’s eyelid slides across the
surface of the contact
lens. Spreading and maintaining the
tear film across the surface of the lens
between each blink is important in
providing a smooth, slippery surface
for reducing friction, sustaining the
integrity of epithelial cells, and maintaining quality optics. Alterations in
the tear film lead to eye complaints
and can have a variety of causes including environmental factors such
as low relative humidity or high room
temperature, demanding task content
such as high demand tasks that reduce
blinking and increases exposed surface area, and individual factors such
as blinking anomalies and contact lens
use (Wolkoff et al, 2005).
The wearing of the contact lens
on the surface of the eye alters the
integrity of the tear film and changes
the evaporation rate (Tomlinson et al,
1982; Korb, 1994; Guillon et al, 2008).
Between blinks, the rapid evaporation
results in tear film break-up that leads
to increases in the local osmolarity of
the tear film (King-Smith et al, 2008)
Increased tear film osmolality that results from tear film thinning (evaporation or dewetting) is believed to be
the cause of contact lens–related dry
eye (Nichols, 2006). Today, contact
lens wearers spend greater amounts of
time using digital devices. To fill the
void in the market for a contact lens
that can meet the changing demands
of patients in an increasingly screencentric world, new approaches to material development are required.
Hydrogel contact lenses have polymer networks with varying waterbinding characteristics. An effective
barrier that retards the evaporation
of the tear film is important for a slow
tear film thinning rate. A long standing challenge of silicone hydrogel
materials has been associated with the
hydrophobic nature of silicone. The
inclusion of silicone into contact lens
materials improves the oxygen permeability of the material; however,
increased levels of silicone result in
increased hydrophobic properties of
the bulk and surface chemistry for the
lens material. As contact lens material
science advanced, methods to make
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
23
NEW CONTAC T LENS
Si
PVP
Si
A
Figure 1. Different approaches for PVP entanglement: (A)
Fully formed PVP integration with silicone (B) PVP grown
around a silicone backbone via MoistureSeal Technology
resulting in 4x more PVP.
silicone hydrogels more wettable progressed from
modification of the surface with plasma treatments
to adjusting the bulk chemistry of the material by
adding wetting agents. In parallel, advancements in
manufacturing capability were needed to compliment
new materials to help ensure the lens is biocompatible and stable over a designated period of lens wear
and lens care.
Unique Chemistry & Polymerization Process
To dramatically improve the effects of material and
surface interaction, more complex strategies must be
applied. This includes development of materials that
withstand a range of user conditions and refinement
of designs and geometries that minimize the impact
of friction and wear. MoistureSeal technology, as part
of the Bausch + Lomb Ultra contact lens material
(samfilcon A), represents a significant achievement in
integrating novel material chemistry and a two-phase
manufacturing process to produce a unique silicone
hydrogel lens designed to address the cycle of discomfort many wearers encounter each day and enhance the overall lens wearing experience particularly
at the end of the day.
MoistureSeal technology uses a unique reaction
sequence that starts with the formation of a silicone
matrix (with high Dk/t and low bulk modulus) followed by the time-delayed addition of internal, permanent wetting agents to drive water content and
surface wettability. In Phase 1 of the polymerization
process, a unique combination of long and short
chain silicone polymers creates a flexible silicone matrix with channels for oxygen transmission. The long
24
■
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
PVP
B
chain silicone provides low modulus while the short
chain silicones provide the majority of oxygen transport capability and structural integrity (for great handling characteristics).
In Phase 2 of MoistureSeal technology, polyvinylpyrrolidone (PVP), a humectant that is highly soluble in water, physiologically compatible, non-toxic,
essentially chemically inert, temperature-resistant,
pH-stable, non-ionic, and colorless is permanently
entangled throughout the silicone matrix. PVP is a
very hydrophilic compound that is frequently used in
medicine, pharmaceutical technology, and cosmetics.
(Folttmann et al, 2008). In fact, PVP has been used in
another silicone hydrogel contact lens (senofilcon A)
successfully.
While other lens manufacturers start with fully
formed, large PVP molecules and then add silicone
(Figure 1 A), MoistureSeal technology starts with
the silicone backbone and polymerizes PVP in-situ
around and throughout the silicone matrix (Figure
1 B). This process of “growing” the PVP from its
molecular building blocks maximizes the utilization
of PVP and results in significantly more PVP (4x as
much of the wetting agent) than the silicone hydrogel
lens material, senofilcon A. Importantly, the manufacturing method that starts with fully formed PVP
molecules cannot achieve the same concentration of
PVP capable through MoistureSeal technology without sacrificing optical clarity of a lens due to phase
separation of the PVP and silicone components. Only
MoistureSeal technology allows for 4x more PVP in
Bausch + Lomb Ultra contact lenses while maintaining optical clarity (Hoteling et al, 2014).
The water-loving polymer PVP is grown permanently around the silicone matrix in order to “hide”
the hydrophobic silicone and to hold water throughout the bulk and at the surface of the lens. The PVP
w w w. c l s p e c t r u m . c o m
NEW CONTAC T LENS
in Bausch + Lomb Ultra contact lenses brings high
water and wettability everywhere on the lens and not
just at its surface. MoistureSeal technology also helps
Bausch + Lomb Ultra contact lenses retain this high
level of water throughout the day.
Surface Wetting and Friction
A wettable contact lens surface is essential to reduce
friction and surface deposition and to improve optical
quality and comfort. Two common assessments used
to evaluate contact lenses at the surface involve measuring wetting angles and coefficients of
friction. These assessments provide insights
regarding the interactions between the lens,
the tears, and the eyelid when the lenses are
worn. When silicone’s hydrophobic structure is more prominent at the surface of the
lens, the contact angle and coefficients of
friction values are higher (Read et al, 2011;
Jacob, 2013). Polymer chemistry and manufacturing processes, such as MoistureSeal
technology play an important role in masking the silicone structure for improved wetting.
Captive bubble contact angles were collected
for the Bausch + Lomb Ultra, Air Optix Aqua (Alcon), Oasys (Vistakon), Biofinity (CooperVision) and
Dailies Total1 (Alcon) silicone hydrogel lenses in
order to assess and compare wettability. To remove
components of the packaging solution from the samples, lenses were rinsed in HPLC grade water prior
to testing. Lenses were placed onto a curved sample
holder and submerged into a quartz cell filled with
HPLC grade water. Advancing and receding captive
bubble contact angles were collected for each silicone
hydrogel lens type.
The advancing angle is believed to represent the
ability of the tear film to fill in dry patches resulting from the breakup of tears, while the receding
angle provides insight on the integrity of the interaction between the surface and the tear (Cheng et al,
2004). A contact angle of 0° indicates complete wetting, values between 0° and 90° indicate the surface
is wettable to varying degrees, and values above 90°
indicate the surface is not wettable. Advancing and
receding contact angle measures indicated surface
wetting was similar between Bausch + Lomb Ultra,
Air Optix Aqua, Oasys, Biofinity and Dailies Total1
lenses (Figure 2 A).
Blinking is essential for maintaining a healthy ocular surface and clarity of vision. The blink cycle includes a fast phase during closure and a slow phase
as the eye reopens (Kwon et al, 2013). As the eye-
lid moves across an opposing surface, it encounters
resistance. Friction forces of Bausch + Lomb Ultra,
Air Optix Aqua, Oasys, Biofinity and Dailies Total1 contact lens materials were investigated using a
novel measurement technique that mimics the applied pressure, sliding speeds encountered by a contact lens on the human eye, and controls for variables
such as temperature and the surface area of lens and
interface interaction.
Coefficient of friction measurements were performed using a rheometer outfitted with specially
During contact lens wear,
friction and wearing down of
the surface are undesirable
characteristics that can impact
the patient experience.
w w w. c l s p e c t r u m . c o m
designed tooling to hold and rub a contact lens immersed in borate buffered saline at 25°C. Static friction was taken as a measure of friction at the start of
the blink phase. Fast and slow kinetic friction was taken as measurements during a constant rotation speed
test to model friction encountered during lid closure
and opening, respectively. Measurements were made
using samples of each contact lens either directly
out of the package or after being worn on-eye for
4 hours. Forces applied to the lenses in this study mimicked eyelid pressure to be more representative of an
in-vivo environment compared to previous studies.
The method is highly reproducible and controlled.
Methods such as glass ramp techniques that lack standardization when comparing different lens materials,
specifically the glass ramp method does not control
the speed of the lens across the control surface, nor
does it quantify the distance that a lens needs to move
down the ramp to achieve constant speed. Constant
speed is a critical variable used to accurately measure
friction between two surfaces. Additionally, the glass
ramp test does not control for the force (or load)
applied to the lens since the surface area of lens material exposed to the glass may vary from lens to lens.
Furthermore, this method cannot discern between
low versus high-speed kinetic friction, which may be
important with respect to the blink phase. All of these
factors may lead to potentially biased outcomes when
comparing different contact lenses when measuring
coefficient of friction using a glass ramp test.
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
25
NEW CONTAC T LENS
Contact Angle
90
80
70
60
50
40
30
20
10
0
Bausch + Lomb
Ultra
(A)
Oasys
Biofinity
Air Optix Aqua
Total1
n Out of Package n After 4h Wear
Static Coefficient of Friction
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
(B)
Bausch + Lomb
Ultra
Oasys
Biofinity
Air Optix Aqua
Total1
n Out of Package n After 4h Wear
Surface Smoothness & Integrity
Fast Kinetic Coefficient of Friction
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
(C)
Bausch + Lomb
Ultra
Oasys
Biofinity
Air Optix Aqua
Total1
n Out of Package n After 4h Wear
Slow Kinetic Coefficient of Friction
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
(D)
Bausch + Lomb
Ultra
Oasys
Biofinity
Air Optix Aqua
Total1
n Out of Package n After 4h Wear
Figure 2. Surface wettability characteristics. (A) Contact
Angle (B) Static Coefficient of Friction (C) Fast Kinetic
Coefficient of Friction (D) Slow Kinetic Coefficient of Friction.
26
■
Mean static and kinetic friction results measured
on a rheometer are presented for unworn (out of
pack) and worn lenses (Figure 2 B-D). Friction at the
initiation of movement was similar for all materials
out of the package, except Dailies Total1, which was
significantly higher than the other lenses (Figure
2B). After wear, the static friction measure indicated
the Air Optix lens and Dailies Total1 had greater
resistance. For fast kinetic measures of friction
(Figure 2C), the Air Optix lens also demonstrated
greater resistance out of package and after wear,
while the Bausch + Lomb Ultra, Oasys, Biofinity,
and Dailies Total1 lenses showed low friction. The
slow kinetic friction measurements demonstrated
that all materials have low friction during this phase
of the blink cycle (Figure 2D).
Bausch + Lomb Ultra lenses demonstrated low coefficient of friction regardless of the simulated blink
speed and performed very consistently even after
4 hours of wear. The high level of wettability and low
friction that MoistureSeal technology provides may
improve the overall wearing experience of patients.
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
During contact lens wear, friction and wearing down
of the surface are undesirable characteristics that
can impact the patient experience. A smooth, durable surface is essential for spreading the tear film,
reducing friction, and providing precision optics.
MoistureSeal technology delivers a lens that withstands the rigors of a planned replacement lens wear
schedule. To demonstrate the smoothness and durability of the Bausch + Lomb Ultra lens surface, Atomic Force Microscopy (AFM) and X-ray Photoelectron Spectroscopy (XPS) were used to evaluate the
morphology, roughness, and elemental composition
of new (unworn) Bausch + Lomb Ultra, Oasys, Biofinity, and Air Optix Aqua contact lenses (Wygladacz
et al, 2014). The impact of a lens care regimen on
surface characteristics was simulated by performing
rub/rinse cycles using renu fresh multi-purpose solution (30 cycles for Bausch + Lomb Ultra, Biofinity,
and Air Optix Aqua; 15 cycles for Oasys). The AFM
assessment provided morphology and surface roughness information and the XPS evaluations provided
insights regarding elemental changes at the surface. Mean surface roughness was compared using a
t-test between new lenses directly out of the blister
to lenses of the same brand/type after simulated wear
cycling (p-value <0.05 was considered significant).
Figures 3 A and B illustrate the surface smoothness of an unworn Bausch + Lomb Ultra lens,
w w w. c l s p e c t r u m . c o m
NEW CONTAC T LENS
A) Bausch + Lomb Ultra
- new
E) Biofinity - new
RMSANT (fresh) = 9.0 ± 6.7 nm
RMSANT (fresh) = 2.6 ± 0.3
B) Bausch + Lomb Ultra
- cycled
F) Biofinity - cycled
RMSANT (cycled) = 2.6 ± 0.5 nm
RMSANT (cycled) = 3.0 ± 1.0 nm
G) Air Optix Aqua - new
C) Oasys - new
RMSANT (fresh) = 4.6 ± 2.8 nm
RMSANT (fresh) = 2.3 ± 0.4 nm
H) Air Optix Aqua - cycled
D) Oasys - cycled
RMSANT (cycled) = 4.1 ± 1.4 nm
RMSANT (cycled) = 10.3 ± 7.0 nm
Figure 3. AFM surface topography images (40 x 40 μm) of new (A) and cycled (B) Bausch + Lomb Ultra
lens surfaces, new (C) and cycled (D) Oasys lens surfaces, new (E) and cycled (F) Biofinity surfaces, and
new (G) and cycled (H) Air Optix Aqua lens surfaces.
w w w. c l s p e c t r u m . c o m
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
27
NEW CONTAC T LENS
and the durability of the Bausch + Lomb Ultra lens
surface that was unaffected by 30 rub/rinse cycles
with an MPS (p=0.145). In addition, the AFM results confirmed the deposition resistance properties
of the samfilcon A material as there were no atomic
element differences between new and cycled
With each blink, it is
essential that the tear
film is distributed and
maintained across the
surface of the lens.
Bausch + Lomb Ultra contact lenses. The Oasys
lenses demonstrated a visible change in roughness
(Figure 3 C and D) with completion of 15 rub/rinse
cycles (p<0.005). The AFM topography images for
new and cycled Biofinity contact lenses showed a significant change in surface roughness (p<0.005). New
Biofinity lenses had randomly distributed rough and
tall domains that were removed and left “pockets” in
the surface with rub/rinse cycling (Figures 3 E and
F). The AFM topography images of new and cycled
Air Optix Aqua lenses demonstrated that the plasmacoated surface was also altered by the 30 rub/rinse
cycles (Figure 3 G and H) (p<0.005). The numerous
cracks on the surface of cycled Air Optix Aqua lenses
resulted in significantly higher concentrations of silicone being detected with the XPS elemental analysis.
The surface analyses demonstrated that even a
gentle lens care system can have an impact on the
surface morphology and exposure of atomic elements
associated with non-wetting chemistry. Oasys, Air
Optix Aqua and Biofinity lenses demonstrated statistically significant changes in surface roughness with
15 (Oasys) or 30 (Air Optix Aqua and Biofinity) rub/
rinse cycles. The Bausch + Lomb Ultra lenses demonstrated no statistically significant changes in surface morphology, roughness, or elemental composition after simulating 1 month of wear.
Summary
Today, new knowledge gained from advances in materials chemistry and manufacturing processes enables
designers to achieve significant improvements in contact lens characteristics. With each blink, it is essential
that the tear film is distributed and maintained across
the surface of the lens. To enhance the lens wearing
28
■
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
experience, a lens must provide a smooth, slippery
surface for reducing friction, sustaining the integrity
of epithelial cells, and maintaining quality optics. The
lens performance must be sustained through varied
environmental conditions, during diverse tasks performed by the contact lens user and over the planned
replacement period. The combined wetting, friction,
durability, dehydration and vision quality testing confirm that the Bausch + Lomb Ultra contact lenses with
MoistureSeal technology can provide an improved
wearing experience for the contact lens wearer. CLS
References
1. Cheng LS, Muller J, Radke CJ. Wettability of silicone-hydrogel contact lenses in the presence of tear-film components.
Curr Eye Res 2004;28(2):93-108.
2. Folttmann H, Quadir A. Polyvinylpyrrolidone (PVP) – One
of the Most Widely Used Excipients in Pharmaceuticals: An
Overview. Drug Delivery Technology 2008;8(6):22-27.
3. Guillon M, C. Maissa C. Contact lens wear affects tear film
evaporation. Eye Contact Lens 2008;34(6): 326-330.
4. Hoteling A, Nichols W, Harmon P, Hook D, Nunez I. PVP
content of a silicone hydrogel material with dual phase polymerization processing. American Optometric Association Annual
Meeting; 2014, Philadelphia, PA.
5. Jacob JT. Biocompatibility in the development of siliconehydrogel lenses. Eye Contact Lens 2013;39(1):13-19.
6. King-Smith PE, Nichols JJ, Nichols KK, Fink BA, Braun RJ.
Contributions of evaporation and other mechanisms to tear
film thinning and break-up. Optom Vis Sci 2008;85(8):623630.
7. Korb DR. Tear film-contact lens interactions. Adv Exp Med
Biol 1994;350:403-410.
8. Kwon KA, Shipley RJ, Edirisinghe M, et al. High-speed camera characterization of voluntary eye blinking kinematics.
J R Soc Interface 2013;10(85):20130227.
9. Nichols JJ, Sinnott LT. Tear film, contact lens, and patientrelated factors associated with contact lens-related dry eye.
Invest Ophthalmol Vis Sci 2006;47(4):1319-1328.
10. Read ML, Morgan PB, Kelly JM, Maldonado-Codina C.
Dynamic contact angle analysis of silicone hydrogel contact
lenses. J Biomater Appl 2011;26(1): 85-99.
11. Tomlinson A, Cedarstaff TH. Tear evaporation from the human eye: the effects of contact lens wear. J Br Contact Lens
Assoc 1982;5:141-150.
12. Wolkoff P, Nojgaard JK, Troiano P, Piccoli B. Eye complaints
in the office environment: precorneal tear film integrity
influenced by eye blinking efficiency. Occup Environ Med
2005;62(1):4-12.
13. Wygladacz KA, Merchea M, Hook D. Comparative Surface
Smoothness Durability of a Novel Silicone Hydrogel Material. Association for Research in Vision and Ophthalmology;
2014 annual meeting.
Bausch + Lomb Ultra and MoistureSeal are trademarks of Bausch
& Lomb Incorporated or its affiliates. All other brand/product names are
trademarks of their respective owners.
US/ZUS/14/0148
w w w. c l s p e c t r u m . c o m
Break the Cycle of Discomfort
™
for unsurpassed comfort & vision all day
1
“It’s like wearing nothing.” —Dr. Greg Usdan, Memphis, TN
See what happens when eye care professionals wear them for the first time at www.BLUltra.com
REFERENCE: 1. Results from a 22-investigator, multi-site study of Bausch + Lomb ULTRA® contact lenses with MoistureSeal® technology, on 327 current silicone hydrogel lens wearers. After 7 days of wear, subjects completed an online
survey. Subjects rated performance across a range of attributes. Preference comparisons represent only those subjects expressing a preference. Ratio is based on the average across the silicone hydrogel lenses represented in the study.
Bausch + Lomb ULTRA and MoistureSeal are trademarks of Bausch & Lomb Incorporated or its affiliates. All other product/brand names are trademarks of their respective owners.
© 2014 Bausch & Lomb Incorporated. US/ZUS/14/0128
NEW PRODUC T
Clinical Performance
of Samfilcon A
Silicone Hydrogel
Contact Lenses
Dr. Steffen is the director
of Clinical Affairs at
Bausch + Lomb, a division
of Valeant Pharmaceuticals.
New technology aims to make lens wear more
comfortable despite increased digital viewing.
By Robert Steffen, OD, MS; Mohinder M. Merchea,
OD, PhD, MBA; Marjorie J. Rah, OD, PhD, &
William Reindel, OD, MS
Dr. Merchea is former
Executive Director, Head of
Medical Affairs, Vision Care
at Bausch + Lomb.
Dr. Rah is Senior Manager,
Medical Affairs Pharmaceuticals & Vision Care
at Bausch + Lomb.
Dr. Reindel is the Medical
Director for Bausch + Lomb
Canada.
30
■
F
55% of American adults report havor over a decade, there
ing a smartphone, 42% own a tablet
have
been
dramatic
computer, and 32% own an e-reader,
changes in materials and
Figure 1 (Pew Research, 2014). These
design of soft contact lensdevices are designed for reading and
es. Clinical performance
use at close range that result in the
advancements were typically led by
eyes constantly refocusing and readvancements in polymer and surface
positioning to process content. With
chemistry and lens design characterisincreased concentration associated
tics. Examples include the integration
with visual tasks on digital devices,
of silicone into hydrogel materials to
increase oxygen transmis100
sibility, enhanced surface
treatments with plasma or
80
internal wetting agents to
improve comfort, and lens
60
design advances to improve vision.
40
Over this same period,
there have been dramatic
20
changes in the way we
0
use our eyes with digi2009
2010
2011
2012
2013
2014
tal display devices. The
Desk/Laptop Computer
Smartphone
types and use of devices
eReader
Tablet/Computer
with smaller screen sizes
Figure 1. Changes in digital display device ownership.
have increased, where
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
w w w. c l s p e c t r u m . c o m
blink rates decrease on average from 15 to 5 blinks
per minute, while the number of incomplete blinks
and tear film break-up time increases (Cardona et al,
2011; Chu et al, 2014; Himbaugh et al, 2009; Jansen
et al, 2010; Patel et al, 1991; Portello et al, 2013).
This in turn may lead to increased lens dehydration
2009
2011
2012
19%
20%
25%
20%
15%
10%
11%
5%
Figure 2. Proportion of contact lens wearers considering
discontinuation.
and symptoms of dryness or discomfort. Overall, the
digital technologies we routinely use can result in
significant challenges for contact lens wearers.
While the advances in contact lens materials and
designs are intended to expand the number of lens
wearers, improve the patient wearing experience,
and reduce the likelihood of patients dropping out of
contact lenses, consumer research indicates that the
number of contact lens wearers considering dropping
out of contact lenses has been increasing (Figure 2)
(Gallup, 2013). For patients considering dropping
out, the most vulnerable time appears to be those
with less than one year of lens wearing experience.
The problems most often experienced relate to discomfort such as dryness and end of day discomfort.
Problems with vision and handling are also commonly experienced by today’s contact lens wearers.
Physiological characteristics of the wearer, physical characteristics of the lens, and characteristics of
the lens wearer’s visual demands and environment
can contribute to the contact lens wearing experience. Unraveling the major causes of discomfort is
complex and difficult for researchers or academics to
assess the reasons for comfort differences between
different contact lenses since they cannot control for
variables independently. For example, a lens material
change would impact modulus, Dk/t, water content
and coefficient of friction among other variables.
Manufacturers on the other hand, have the ability to
w w w. c l s p e c t r u m . c o m
control these variables independently as they can alter polymer formulations and lens designs and then
evaluate the clinical impact of each variable. Not
surprisingly, an extensive review of the literature revealed that there are few proven links between contact lens discomfort and factors related to current
contact lens material, the lens design, or
the care system (Jones et al, 2013). Simi2013
larly, a thorough review of the research
associated with the tear film indicated
that no single biophysical component
could be singled out as responsible for
18%
discomfort (Craig et al, 2013). However,
in considering other biophysical interactions, meibomian gland dysfunction and
lid wiper epitheliopathy demonstrated
the strongest link to contact lens discomfort (Efron et al, 2013).
In a survey of over 800 contact lens
wearers, 72% indicated they would be
very or quite disappointed if they could
no longer wear their contact lens (Gallup, 2013).
Therefore, to maintain patient satisfaction with the
care provided, it is important for eye care practitioners to help patients continue with their favored vision correction. While a comprehensive assessment
and intervention commonly occurs when a patient
expresses dissatisfaction, the introduction of new
technology offers practitioners the opportunity to
address common complaints or provide patients with
a more successful experience.
Before adopting new technology eye care practitioners will typically ask about its effectiveness in
the real world. By allowing wide patient selection
criteria, data collected in a “real world” evaluation
captures clinically important information relevant
to a particular population or treatment. Real world
clinical evaluations can broaden knowledge of patient
outcomes and can capture valuable, real-time patient
data that is not present in controlled clinical trials.
The purpose of this study was to evaluate the performance of the Bausch + Lomb Ultra contact lenses
with MoistureSeal technology and advanced aspheric
optics when worn by experienced silicone hydrogel
contact lens wearers.
Study Design
This was a prospective, single arm, open-label clinical study. Independent eye-care practitioners from 22
investigational sites enrolled patients. Institutional
review board approval was obtained for the study,
and patients signed an informed consent form. To be
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
31
NEW PRODUC T
included in the study, patients needed to:
• Spend at least 3 hours each workday using a
computer or electronic device (i.e. smartphones, tablets, eReaders)
• Subjects were myopic and required lens correction from -0.25 D to -6.00 D in each eye
• Have worn their current lens brand for a minimum of one year
• Wear their current lenses for a minimum of
12 hours per day at least four days per week
• Be between the ages of 18 and 35 years
• Have <= Grade 1 for corneal and conjunctival
assessments (see below)
• Be absent of any corneal infiltrates
At the initial visit, patients rated symptoms associated with their habitual brand of lenses using a 0-100
scale, with 0 denoting the least favorable rating and
100 denoting the most favorable score. To add context, descriptors were added to the rating scale for
each category. As an example, the “end-of-day comfort” category designated 100 as “excellent; cannot be
felt,” 80 as “very comfortable; just felt occasionally,”
60 as “comfortable; noticeable but not irritating,”
40 as “uncomfortable; irritating or annoying,” 20 as
“very uncomfortable; very irritating or annoying,”
and 0 as “painful; difficult to wear lenses.”
Practitioners completed a slit lamp evaluation
using a five-point scale. Slit lamp signs of epithelial
edema, epithelial microcysts, corneal staining, limbal
injection, bulbar injection, tarsal conjunctival abnormalities, corneal neovascularization, and corneal infiltrates were graded using an ordinal, text-based scale
from which numeric grades in integer steps were assigned, 0 (no finding), 1 (trace), 2 (mild), 3 (moderate) and 4 (severe). Patients with any graded infiltrate
were not eligible for participation. For the remainder
of graded signs, patients with findings greater than
grade 1 were not eligible to participate. Practitioners
also collected sphero-cylindrical refraction, slit lamp
evaluation, lens centration and movement, and visual
acuity (VA).
Patients were re-fitted to Bausch + Lomb Ultra
contact lenses with MoistureSeal technology and
Biotrue multi-purpose solution for 2 weeks. After the
first seven days of product use, subjects responded to
a Web-based subjective assessment evaluating comfort, wettability, lens cleanliness, and other compo-
T A B L E
1
Subject demographics and baseline eye characteristics.a
TOTAL
AIR OPTIX
AQUA
N = 132
BIOFINITY
N = 341
ACUVUE
OASYS
N = 130
26.8
27.4
26.5
26.2
18, 35
18, 35
18, 35
19, 35
Female
69.5
66.2
69.7
74.7
Male
30.5
33.8
30.3
25.3
Mean/Median
-3.36/-3.25
-3.37/-3.00
-3.23/-3.125
-3.54/-3.50
Min, max
-6.75, -0.25
-6.50, -0.25
-6.75, -0.75
-6.50, -1.00
Mean/Median
-0.21/0.00
-0.21/ 0.00
-0.20/ 0.00
-0.23/-0.25
Min, max
-0.75, 0.00
-0.75, 0.00
-0.75, 0.00
-0.75, 0.00
N = 79
Age
Mean
Min, max
Gender (%)
b
Diagnostic refraction
spherec,D
Diagnostic refraction
cylinderc,D
a Demographics and baseline eye characteristics are reported for eligible, dispensed subjects/eyes.
b Percentages are based on the number of subjects with responses.
c Diagnostic refraction sphere and cylinder are summarized at the eye level, while all other parameters are summarized at the subject level.
32
■
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
w w w. c l s p e c t r u m . c o m
NEW PRODUC T
nents of satisfaction with daily contact lens wear.
Patient questionnaires were completed outside of the
practitioner’s office to help ensure a higher level of
objectivity.
After 14 days of wear, the patients rated symptoms
associated with the Bausch + Lomb Ultra contact
lenses. Practitioners once again collected spherocylindrical refraction, slit lamp evaluation, lens centration and movement, and visual acuity (VA: made
using logMAR acuity charts). In addition, practitioners provided their perspective on satisfaction overall
and ease of fit through an on-line survey.
T A B L E
2
Habitual brands of contact lens
care solutions
Brand
% of
Patients
Alcon Opti-Free Express
Multi-Purpose
4.7
Alcon Opti-Free RepleniSH
Multi-Purpose
13.2
Alcon Opti-Free PureMoist
16.4
Alcon/CIBA Vision AQuify
Multi-Purpose
1.8
Continuous data was summarized using descriptive
statistics: n, mean, standard deviation, minimum,
and maximum. The differences in continuous endpoints between study visits were assessed using paired
t-tests. The differences in dichotomous categorical
endpoints between study visits were assessed using
McNemar’s tests. The p-values presented were twosided, and evaluated using a 0.05 alpha level for each
comparison. There were no interim analyses.
Alcon/CIBA Vision ClearCare
10.6
AMO Complete Easy Rub
Multi-Purpose
2.9
AMO RevitaLens Multi-Purpose
Disinfecting Solution
0.6
Bausch + Lomb Biotrue
Multi-Purpose solution
22.6
Bausch + Lomb renu fresh (ReNu
MultiPlus) Multi-Purpose Solution
10.0
RESULTS
Study Subjects
Bausch + Lomb renu sensitive
(ReNu) Multi-Purpose Solution
1.8
Other Including Store Brand MPS
(e.g. Walmart, Target, Publix)
15.4
Statistical Methods
Three hundred forty one silicone hydrogel patients
were enrolled: 132 Acuvue Oasys (Vistakon) patients,
130 Air Optix Aqua (Alcon) wearers, and 79 Biofinity (CooperVision) wearers. Table 1 lists study subject
demographics and baseline eye characteristics for the
total population of dispensed patients and the three
habitual lens cohorts. Average age for the study population was 26.8 years with 69.5% being female and
30.5% male. The median refractive sphere and cylinder power was -3.25 D and 0.00 D, respectively. A
comparison of habitual contact lens powers to study
contact lens powers indicated that 92.7% of lenses
were within +/- 0.25D. The most common branded
contact lens care products used prior to entering the
evaluation were Biotrue Multi-Purpose (22.6%) and
Opti-Free PureMoist by Alcon (16.4%), Table 2.
The average daily wear time with habitual lenses
was 13.9 hours. During a typical day, the study population spent an average of 4.8 hours using a computer/laptop at the office and an average of 1.9 hours
at home, Table 3. In addition, other digital devices
(smartphone/tablet/e-Book) were used an average of
3.1 hours. Playing electronic games was reported to
have the least amount of activity of those surveyed.
Table 4 presents the Snellen-equivalent, contact
lens VA measures for the habitual lenses and dispensed
w w w. c l s p e c t r u m . c o m
T A B L E
3
Average hours spent doing each
activity on a typical day
Activity
Avg. Hours
Driving at night
1.1
Watching TV
2.0
Using a computer/laptop at Office
4.8
Using a computer/laptop at Home
1.9
Looking at a Smartphone/
Tablet/E-book
3.1
Reading books/magazines/
newspapers
1.4
Playing electronic games
0.4
Bausch + Lomb Ultra lens at the dispensing visit
and for the Bausch + Lomb Ultra lens at the 2-week
follow-up visit. For these acuity measures completed
in-office, the proportion of eyes with VA better than
or equal to 20/20 were similar: 92.2% for the habitual
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T O N 2 0 1 4 ■
33
NEW PRODUC T
T A B L E
reports of corneal exposure at either visit. Adequate lens movement was reported for 95.7%
of eyes at the dispensing visit and 96.6% of
eyes at the follow-up visit. There were no reports of lens adherence at either visit.
4
Snellen equivalent Visual Acuity for
Habitual lens and Bausch + Lomb Ultra lens
Snellen
Equivalent
20/9.5
20/12.5
20/16
20/20
20/25
20/32
20/40
Worse than
20/40
Habitual @
Dispensing
Visit
Bausch +
Lomb Ultra
@ Dispensing Visit
Bausch +
Lomb Ultra
@ 2-week
Visit
0.3%
6.2%
41.1%
44.6%
6.7%
1.0%
0.1%
0.6%
10.0%
46.3%
38.7%
3.7%
0.7%
0.0%
0.9%
10.2%
46.8%
35.4%
5.8%
0.5%
0.3%
0%
0%
0.1%*
Slit Lamp Findings
Slit lamp findings for each eye were graded
for severity on a scale of 0 (no finding) to
4 (severe finding). Subjects were not enrolled into the study if habitual lens slit lamp
findings of grade 2 or higher were present.
Results from the dispensing visit (habitual
lens) and the follow-up visit (after wearing
Bausch + Lomb Ultra) are summarized in
Table 5 for the dispensed eyes. At the 2-week
follow-up visit, only 2 eyes (0.3%) had findings greater than grade 2.
* No reduction in best spectacle corrected visual acuity was observed for this
subject’s eye as Snellen acuity was 20/20 at both baseline and exit.
lenses, 95.6% for the Bausch + Lomb Ultra lens at
dispensing visit, and 93.3% for Bausch + Lomb Ultra
lens at the 2-week visit.
Fit Characteristics
Bausch + Lomb Ultra contact lenses were fully centered
for 92.7% of eyes at the dispensing visit and for 95.1%
of eyes at the follow-up visit, Table 5. There were no
Symptoms
The in-office mean ratings of symptoms
associated with the subject’s habital lenses and symptoms associated with the Bausch + Lomb Ultra
contact lenses are summarized in Table 6. The
difference between the habitual baseline and
Bausch + Lomb Ultra ratings at the 2-week visit was
evaluated for statistical differences. All categories
evaluated had ratings statistically more favorable for
T A B L E
5
Table 5. Graded slit lamp findings for dispensed eyes
Condition
34
■
Dispensing Visit
Follow-up Visit
Grade
None
Trace
Mild
Moderate
Severe
None
Trace
Mild
Moderate
Severe
Epithelial
Edema
100
0.0
0.0
0.0
0.0
99.6
0.4
0.0
0.0
0.0
Epithelial
Microcysts
99.4
0.6
0.0
0.0
0.0
99.7
0.3
0.0
0.0
0.0
Corneal
Staining
78.5
21.5
0.0
0.0
0.0
75.3
22.5
2.1
0.1
0.0
Limbal
Injection
91.7
8.3
0.0
0.0
0.0
94.6
4.9
0.4
0.1
0.0
Bulbar
Injection
87.2
12.8
0.0
0.0
0.0
89.4
10.1
0.3
0.1
0.0
Tarsal
Conjunctival
Abnormalities
75.6
24.4
0.0
0.0
0.0
74.9
25.0
0.1
0.0
0.0
Corneal
Neovascularization
98.0
2.0
0.0
0.0
0.0
98.1
1.9
0.0
0.0
0.0
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
w w w. c l s p e c t r u m . c o m
NEW PRODUC T
the Bausch + Lomb Ultra contact lenses with
the exception of Ease of Handling at Insertion which was not statistically significantly
different. The largest differences favoring
the Bausch + Lomb Ultra contact lenses
were associated with comfort at end of day,
(less) dryness, lens cleanliness upon removal,
and vision in low light (p<0.05).
Patient Experiences
T A B L E
6
Mean rating for each symptom category
using a scale of 0–100 (100 represents
the most favorable rating) at baseline
(Habitual) and after 2 weeks of wear.
Comfort Upon
Insertion
Habitual
Bausch +
Lomb Ultra
Difference†
81.4
86.5
+ 5.5*
Through the on-line survey, subjects rated
Comfort at End
62.8
75.4
+12.9*
performance attributes in various realof
Day
world situations. Overall, 87.4% rated the
Dryness
68.5
80.9
+12.8*
Bausch + Lomb Ultra contact lenses as either
“excellent,” “very good,” or “good.” Accep84.8
89.0
+4.5*
Redness
tance ratings for vision and comfort experi88.5
89.7
+1.5*
Vision
ences associated with Bausch + Lomb Ultra
80.5
87.4
+7.2*
Vision
in
Low
were very high, Table 7. The proportions of
Light
subjects in agreement with the different perLens Cleanliness
87.3
90.6
+3.4*
formance statements associated with vision
Upon
Insertion
and comfort experiences were statistically
Lens Cleanliness
76.7
85.4
+8.8*
significantly greater than 50%. Clear vision
Upon
Removal
throughout the day (88.7%), when driving
at night (88.0%), and when focusing for a
Ease of Handling/
87.0
86.8
-0.2
Insertion
long time at digital devices (87.4%) offered
the highest agreement ratings. For comfort,
Ease of Handling/
85.2
89.5
+4.3*
the highest agreement ratings were for when
Removal
driving at night (88.3%) and when focusing
for a long time at digital devices (85.3%).
†
Positive values indicate Bausch + Lomb Ultra lens rating is more favorable
Preference results associated with
than Habitual lens rating
comfort and vision are presented in
*Statistically significant p<0.05
Figure 3 and 4, respectively. In comparing
Bausch + Lomb Ultra contact lens vision and
comfort performance to the subject’s habitual lens,
experience was preferred for prevention of tired/fapreference differences were statistically significant
tigued eyes when focusing for a long time at digital
for the total cohort and for each of the individual silidevices (3.0:1).
cone hydrogel lens brands (p<0.05). For all subjects
with a preference, the Bausch + Lomb Ultra lens exInvestigator Perspectives
perience was preferred for comfort: when working
Following the completion of each subject, the cumulong hours on a computer (3.7:1), when focusing for
lative investigator satisfaction ratings demonstrated
a long time at digital devices (3.2:1), in dry environoverall satisfaction with the outcomes for 98.2% of paments (3.0:1) and while driving at night (4.3:1). The
tients. Based on the performance and fit characteristics,
Bausch + Lomb Ultra contact lens experience was
investigators indicated that the Bausch + Lomb Ultra
contact lens was easy to fit for 98.9% of the patients
preferred for clear vision: when working long hours
evaluated (Figure 5).
on a computer (4.6:1), when focusing for a long time
at digital devices (3.8:1), in dry environments (2.7:1)
Discussion
and while driving at night (5.3:1).
To evaluate product performance, “real-world” nonOverall, 78.8% of patients agreed that
randomized, prospective studies are used in broader
Bausch + Lomb Ultra contact lenses prevent eyes
patient populations and special patient subsets in
from feeling tired or fatigued even when you focus
general medicine (Beusterien et al, 2013; Boeru et al,
for a long time at digital devices. For all subjects with
2013; Chaudhuri et al, 2014; Ge et al, 2011; Han et al,
a preference, the Bausch + Lomb Ultra contact lens
w w w. c l s p e c t r u m . c o m
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
35
NEW PRODUC T
T A B L E
2011) and optometry/ophthalmology (Blini
et al, 2009; Crichton et al, 2010; Denis et
al, 2010; Stonecipher et al, 2005).The patients enrolled in this prospective, nonrandomized, open-label multi-center trial used
various digital devices throughout their day
that accumulated to over 9 hours (average).
The Bausch + Lomb Ultra contact lens
with MoistureSeal technology is designed
to meet the demands of today’s contact lens
users. Long hours using digital display devices with infrequent and incomplete blinks
can create wearing comfort and vision challenges that previous generations of silicone
hydrogel lenses may not have been designed
to address. In this study sample of current
silicone hydrogel wearing patients, the
Bausch + Lomb Ultra contact lens improved
the wearing experience associated with comfort and vision. The in-office assessment
of comfort symptoms indicated that the
Bausch + Lomb Ultra contact lens provided significant improvements in end-ofday comfort and a reduction in dryness.
7
Extent of agreement by subjects with
attributes of Vision and Comfort
Provide clear vision…
% Agree
Throughout the day
88.7%
In dry environments
80.4%
When working for long hours at a computer
83.7%
When driving at night
88.0%
When focusing for a long time at digital devices
87.4%
Comfortable…
% Agree
Throughout the day
82.2%
In dry environments
79.1%
When working for long hours at a computer
82.2%
When driving at night
88.3%
When focusing for a long time at digital devices
85.3%
Prevent eyes from feeling tired or fatigued
even when you focus for a long time at digital
devices.
78.8%
56.4
Throughout the day
18.7
54.9
In dry environments
18.4
59.5
When working for long hours at a computer
16.3
52.7
When driving at night
12.3
61
When focusing for a long time at digital devices
17.2
51.2
Prevent eyes from feeling tired or fatigued
when focusing for a long time at digital devices
16.9
0
10
Bausch + Lomb Ultra Preferred
20
30
40
50
60
70
Habitual Preferred
Figure 3. Percent of subject preference for comfort attributes
36
■
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
w w w. c l s p e c t r u m . c o m
NEW PRODUC T
52.5
Throughout the day
14.4
52.1
In dry environments
19.6
59.2
When working for long hours at a computer
12.9
53.7
When driving at night
10.1
51.8
When focusing for a long time at digital devices
13.8
0
10
Bausch + Lomb Ultra Preferred
20
30
40
50
60
70
Habitual Preferred
Figure 4. Percent of subject preference for providing clear vision in real world conditions
When asked to assess lens comfort in various real
world situations, the on-line survey substantiated the
acceptability of the Bausch + Lomb Ultra contact
lenses when worn in dry environments, when focusing for a long time at digital devices and when using
a computer for a long time. The improvements in
comfort were noted in patients re-fitted from Acuvue
Oasys, Air Optix Aqua, and Biofinity contact lenses.
W i t h M o i s t u r e S e a l t e c h n o l o g y, t h e
Bausch + Lomb Ultra contact lens is designed to retain moisture and provide a smooth optical surface
to help prevent dehydration blur. The advanced
aspheric optics design can also help reduce blurred
vision, halos and glare in low light conditions.
Although the “in-the-chair” Snellen visual acuity
measurements were similar between the habitual and
Bausch + Lomb Ultra lenses, the Bausch + Lomb Ultra
contact lens performance results highlighted improvements in the wearing experience associated
with vision in real world situations that cannot be
simulated in a practice environment. Both the inoffice assessment of vision symptoms and the on-line
survey substantiated improvements when wearing
the Bausch + Lomb Ultra contact lenses compared to
the habitual silicone hydrogel lenses. The preference
associated with clear vision when working long hours
on a computer and while driving at night indicate
w w w. c l s p e c t r u m . c o m
that the Bausch + Lomb Ultra lens advancements will
provide an improved lens wearing experience.
Throughout the evaluation, there were no device related adverse events reported. Slit lamp findings revealed that 99.7% of eyes had minimal findings (no findings or trace or mild findings). Only
two eyes associated with two patients had slit lamp
findings greater than grade 2. With all subjects using Biotrue multi-purpose solution, these low level
of findings highlight the biocompatibility of both the
Bausch + Lomb Ultra contact lens and Biotrue multipurpose solution.
Investigators assessed centration and movement
fitting characteristics at dispensing and after two
weeks of wear. There were no reports of corneal
exposure or lens adherence at either visit. Together
with the fit, vision, and symptoms reports collected at
all visits, practitioners expressed high levels of satisfaction overall (93.2%) and satisfaction with the ease
of fit (98.9%).
Visual tasks connected with digital displays have
been associated with changes in rate of blinks, the
extent of blinks and the integrity of the tear film
(Cardona et al, 2011; Chu et al, 2014; Himbaugh et
al, 2009; Jansen et al, 2010; Patel et al, 1991; Portello et al, 2013). These alterations in blink patterns
are also related to symptoms of dryness, discomfort,
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
37
NEW PRODUC T
7. Portello JK, Rosenfield M, Chu CA. Blink rate, incomplete blinks and computer vision syndrome. Optom Vis Sci.
2013;90(5):482-487.
8. Multi-Sponsor Surveys’ 2013 Gallup Study of the U.S. Contact Lens Market.
9. Jones L, Brennan NA, Gonzalez-Meijome J, et al. The TFOS
International Workshop on Contact Lens Discomfort: report
of the contact lens materials, design, and care subcommittee.
Invest Ophthalmol Vis Sci. 2013;54(11):TFOS37-70.
93.2
A
Satisfied
98.9
B
Not Satisfied
Figure 5. Percent practitioner satisfaction Overall (A) and
Ease of Fit (B)
blurred vision and visual fatigue. The extensive use
of visual display activities by the patients in this study
likely contributed to their reported symptoms of dryness, tired eyes, eye strain, blurriness or fluctuating
vision when they entered the evaluation.
While previous silicone hydrogel contact lenses
have made advancements in material chemistry and
design, discomfort, blurry vision and cessation of lens
wear continue to challenge contact lens wearers and
eye care practitioners. With the MoistureSeal technology and aspheric optics, the Bausch + Lomb Ultra
contact lenses deliver improved comfort and vision
wearing experience for patients. As vision demands
associated with digital display devices increase, the
Bausch + Lomb Ultra contact lens with MoistureSeal
technology offers eye care practitioners a valuable
tool for meeting patient’s needs. CLS
References
1. Device Ownership Over Time, Pew Research Center’s
Internet & American Life Project. 2/15/2014. Available at:
pewinternet.org/data-trend/mobile/device-ownership/
2. Cardona G, Garcia C, Seres C, Vilaseca M, Gispets J. Blink
rate, blink amplitude, and tear film integrity during dynamic
visual display terminal tasks. Curr Eye Res. 2011;36(3):190-197.
3. Chu CA, Rosenfield M, Portello JK. Blink patterns: reading
from a computer screen versus hard copy. Optom Vis Sci.
2014;91(3):297-302.
4. Himebaugh NL, Begley CG, Bradley A, Wilkinson JA. Blinking and tear break-up during four visual tasks. Optom Vis Sci.
2009;86(2):E106-114.
5. Jansen ME, Begley CG, Himebaugh NH, Port NL. Effect of
contact lens wear and a near task on tear film break-up. Optom
Vis Sci. 2010;87(5):350-357.
6. Patel S, Henderson R, Bradley L, Galloway B, Hunter L. Effect of visual display unit use on blink rate and tear stability.
Optom Vis Sci. 1991;68(11):888-892.
38
■
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
10. Craig JP, Willcox MD, Argueso P, et al. The TFOS International Workshop on Contact Lens Discomfort: report of the
contact lens interactions with the tear film subcommittee.
Invest Ophthalmol Vis Sci. 2013;54(11):TFOS123-156.
11. Efron N, Jones L, Bron AJ, et al. The TFOS International
Workshop on Contact Lens Discomfort: report of the contact lens interactions with the ocular surface and adnexa subcommittee. Invest Ophthalmol Vis Sci. 2013;54(11):TFOS98TFOS122.
12. Beusterien K, Tsay S, Gholizadeh S, Su Y. Real-world experience with colorectal cancer chemotherapies: patient web
forum analysis. Ecancermedicalscience. 2013;7:361.
13. Boeru G, Milanov I, De Robertis F, et al. ExtaviJect(R) 30G
device for subcutaneous self-injection of interferon beta-1b
for multiple sclerosis: a prospective European study. Medical
devices. 2013;6:175-184.
14. Chaudhuri N, Duck A, Frank R, Holme J, Leonard C. Real
world experiences: pirfenidone is well tolerated in patients
with idiopathic pulmonary fibrosis. Respiratory medicine.
2014;108(1):224-226.
15. Ge JB, Zhang F, Qian JY, Ge L, Liu XB, Zhou J. Six-month
clinical outcomes of Firebird 2TM sirolimus-eluting stent
implantation in real-world patients with coronary artery
diseases. Chin Med J (Engl). 2011;124(6):831-835.
16. Han YL, Chen JY, Xu B, et al. Real world clinical performance of the zotarolimus eluting coronary stent system in
Chinese patients: a prospective, multicenter registry study.
Chin Med J (Engl). Oct 2011;124(20):3255-3259.
17. Blini M, Rossi GC, Trabucchi G, et al. Ocular hypotensive
efficacy and safety of travoprost 0.004% in inadequately controlled primary open-angle glaucoma or ocular hypertension:
short-term, multicenter, prospective study. Current medical
research and opinion. 2009;25(1):57-63.
18. Crichton AC, Harasymowycz P, Hutnik CM, et al. Effectiveness of dorzolamide-timolol (COSOPT) in patients who
were treatment naive for open-angle glaucoma or ocular
hypertension: the COSOPT first-line study. J Ocul Pharmacol Ther. 2010;26(5):503-511.
19. Denis P, Baudouin C, Bron A, et al. First-line latanoprost
therapy in ocular hypertension or open-angle glaucoma
patients: a 3-month efficacy analysis stratified by initial intraocular pressure. BMC Ophthalmol. 2010;10:4.
20. Stonecipher K, Perry HD, Gross RH, Kerney DL. The
impact of topical cyclosporine A emulsion 0.05% on the
outcomes of patients with keratoconjunctivitis sicca. Current
Medical Res Opin. Jul 2005;21(7):1057-1063.
Bausch + Lomb Ultra, MoistureSeal, renu, ReNu Multiplus, and
Biotrue are trademarks of Bausch & Lomb Incorporated or its affiliates.
All other product/brand names are trademarks of their respective owners.
US/ZUS/14/0124
w w w. c l s p e c t r u m . c o m
LENS DEHYDR ATION
Preventing
Dehydration Blur
Ms. Hovinga is a biomechanical design engineer and is
part of the Lens Design group
at Bausch + Lomb.
The increased use of digital devices in today’s
society has made it more important than ever
to address lens dehydration.
B y K ri s t e n R . H ov i n g a , M S; Pa u l D. L u d i n g to n , M S;
M o h i n d e r M e r c h e a , O D, P h D, M B A & R o b e r t St e f f e n , O D, M S
Mr. Ludington has more than
30 years of experience in
optical design and engineering, having worked at Bell
Labs, Eastman Kodak and
now at Bausch + Lomb. He is
responsible for development
of metrology for contact
lenses.
Dr. Merchea is former
Executive Director, Head
of Medical Affairs, Vision
Care at Bausch + Lomb.
Dr. Steffen is the director
of Clinical Affairs at
Bausch + Lomb, a division
of Valeant Pharmaceuticals.
w w w. c l s p e c t r u m . c o m
W
e live in a screencentric
world
where consumers spend more
than 10 hours
a day using technology or electronic
devices (Ipsos, 2012) and contact lens
wearers are still looking for a lens
that consistently provides comfort
and clear vision throughout the day.
With previous generations of contact
lenses, patients have reported lower
satisfaction and increased risk of dropping out of contact lens wear with increased hours of use of digital devices
(Kadence, 2013).
One challenge associated with sustained visual tasks such as focusing
on digital device screens is preventing lens dehydration and maintaining the pre-lens tear film (PLTF)
between successive blinks. Sustained
visual tasks are also known to reduce
blink rates (Bentivoglio et al, 1997;
Cardona et al, 2011; Himebaugh et al,
2009; Portello et al, 2013). In general,
the literature suggests that the resting
average blink rate of 15 times per minute may be reduced to an average of
5 times per minute (Bentivoglio et al,
1997; Cardona et al, 2011; Himebaugh
et al, 2009; Portello et al, 2013).
The quality and stability of the
PLTF affects both the comfort and
visual experience of the contact lens
wearer. In one study, sixty percent of
contact lens wearers who experienced
symptoms of blurry or fluctuating
vision felt that these symptoms had a
negative impact on contact lens comfort (Donnelly 2013). Ideally the PLTF
would remain stable for the same period of time as the pre-corneal tear film
of the non-lens wearer. In reality however, the lens alters the normal structure and evaporation of the tear film
and these factors have been associated
with contact lens discomfort and can
reduce visual quality (Guillon et al
2008; Korb, 1994).
PLTF stability is affected by both
the magnitude and rate of water loss
across the anterior surface of the lens
(Nichols et al, 2006). Different contact
lens materials behave differently in
their ability to resist dehydration and
maintain a consistent optical surface
for great vision. Minimizing water loss
across the surface of a lens may help
to maintain a stable tear film, giving
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
39
LENS DEHYDR ATION
Figure 1. Optical imaging bench layout
a consistent optical surface, providing greater visual
stability within typical blink rates at rest or during
sustained visual tasks.
Methods
To evaluate image quality during a simulated blink
cycle, thirty (30) single vision contact lenses of
Bausch + Lomb Ultra (samfilcon A), Acuvue Oasys
(Vistakon – senofilcon A), Air Optix Aqua (CibaVision
– lotrafilcon B) and Biofinity (CooperVision – comfilcon A) were measured using a novel optical bench
technique. This in-vitro method predicts the logMAR
retinal image quality based on the measured optical
image resolution and contrast as the PLTF changes
over time.
Figure 1 shows the optical layout of the imaging
bench. The target was a chrome-on-glass US Air
Force 1951 target. This target object was imaged
through a Badal lens, the contact lens under test, a
model cornea, and a 67D lens. The aerial image is
then magnified by 10X onto a monochrome CCD
camera.
The aspheric model cornea is diamond-turned
from polymethylmethacrylate (PMMA) and mimics
the optics and physical dimensions of an average human eye with a 7.8mm radius and +0.18mm of spherical aberration over a 6mm pupil. The USAF target
(Figure 2) contains a series of horizontal and vertical
3-bar patches that represent specific spatial frequencies expressed as line pairs per millimeter. These spatial frequencies can be used to determine the contrast
(the white letters against the black background) and
resolution (the clearness or sharpness of the vertical
and horizontal lines) thresholds for a contact lens
when conformed to a model cornea. An image quality metric which incorporates a cross-correlation algorithm for determining resolution and contrast was
used on each of the USAF target images to generate
a predicted logMAR visual acuity score for each lens.
This easily understood metric provides a value which
can be used to quantitatively assess changes in image
quality for each lens over time.
Each lens was initially blotted to remove excess
packaging solution from the lens surface and was
conformed to the PMMA model cornea. Two drops
of rewetting solution were used to simulate a fresh
tear film after a blink. Multiple images of the USAF
target were captured through each lens under ambient room conditions (70ºF and 50% RH). Images
were acquired every second for a total of 30 seconds
and the predicted logMAR score for each lens at each
time point were averaged for the 30 lenses measured
for each brand. A Two Way – Repeated Measures
ANOVA was conducted on the individual predicted logMAR scores using time and lens type as the
main effects. Post-hoc analysis was performed using
Tukey’s HSD test.
Results
Figure 2. USAF 1951 target
40
■
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
Figure 3 shows USAF target images representing the
average logMAR score for each lens type captured at
every ten-second time point. These images represent
w w w. c l s p e c t r u m . c o m
LENS DEHYDR ATION
Bausch + Lomb Ultra
Acuvue Oasys
Air Optix Aqua
Biofinity
Figure 3. USAF images over a time frame simulating a range representing a blink cycle up to 30 seconds
the image quality produced by each lens type over a
30 second time period. The Bausch + Lomb Ultra lens
remained consistent with respect to the clarity of the
images over the entire 30 second period. Other lens
types showed reduced overall image contrast (image
appears grayer) or reduced image clarity (smallest bar
targets are not visible).
Different contact lens
materials behave
differently in their ability
to resist dehydration
and maintain a consistent
optical surface.
Figure 4 shows the mean predicted logMAR as a
function of time for each lens, along with the ± one
standard deviation for the sample of (30) lenses for
each lens type. From this graph, it is evident that
the Bausch + Lomb Ultra lens provides better image
clarity and stability over time compared to the other
products tested.
w w w. c l s p e c t r u m . c o m
The Bausch + Lomb Ultra lens demonstrated better predicted logMAR scores at time-zero and at each
additional time (10s, 20s, and 30s) compared to the
three commercial lens products (p < 0.01 in all cases).
At time-zero, the Bausch + Lomb Ultra lens
had at least a one-line improvement in predicted
logMAR acuity compared to the other three silicone hydrogel lenses. Additionally, after 30s, the
Bausch + Lomb Ultra lens had a 1.7 line average
improvement over the lenses.
Discussion
With the increased use of digital devices over the
last several years, patients have reported lower satisfaction and increased risk of dropping out of contact lens wear as they spend more time using digital
devices (Kadence 2013). Recommending a contact
lens that improves patient experiences in these visual
environments may improve patient satisfaction and
retention in contact lens wear.
The ability of a contact lens material to resist dehydration and maintain or stabilize the pre-lens tear
film (PLTF) may help to provide a more consistent
optical surface. Dehydration blur has been shown to
be variable across different contact lens materials, and
this may have a significant impact on visual quality
and overall comfort that a patient experiences in contact lens wear in a variety of visual environments.
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
41
LENS DEHYDR ATION
The better visual quality and predicted logMAR
scores with Bausch + Lomb Ultra compared to the
other leading silicone hydrogel lenses in the market
is supported by aspheric optics and unique lens material properties that allow the lens material to help
resist dehydration. Bausch + Lomb Ultra lenses start
off clearer and remain clearer over the full 30 second
test period in this in-vitro model designed to demonstrate the inherent ability of the lens material to
resist dehydration. The 30-second time period is longer than the average inter-blink period that the vast
majority of patients would experience, even under
reduced blink rate situations such as with the use of
digital devices. CLS
3. Bentivoglio AR, Bressman SB, Cassetta E, Carretta D, Tonali P,
Albanese A. Analysis of blink rate patterns in normal subjects.
Movement disorders: official journal of the Movement Disorder
Society. Nov 1997;12(6):1028-1034.
References
9. Korb DR. Tear film-contact lens interactions. Adv Exp Med
Biol. 1994;350:403-410.
1. Ipsos OTX and Ipsos Gobal @dvisor. Socialogue: If You’re
Awake, Chances Are You Are Well-Connected. Available at:
http://www.ipsos-na.com/news-polls/pressrelease.aspx?id=5725.
Last accessed July 21, 2014.
2. Kadence International. Exploring Contact Lens Drop-off.
May 2013.
4. Cardona G, Garcia C, Seres C, Vilaseca M, Gispets J. Blink rate,
blink amplitude, and tear film integrity during dynamic visual
display terminal tasks. Curr Eye Res. Mar 2011;36(3):190-197.
5. Himebaugh NL, Begley CG, Bradley A, Wilkinson JA. Blinking
and tear break-up during four visual tasks. Optom Vis Sci. Feb
2009;86(2):E106-114.
6. Portello JK, Rosenfield M, Chu CA. Blink rate, incomplete
blinks and computer vision syndrome. Optom Vis Sci. May
2013;90(5):482-487.
7. Donnelly C, Nandakumar K, Raj S. Symptoms in CL wear —the
unmet needs of the CL wearer. Optician. June 7, 2013:16-22.
8. Guillon M, Maissa C. Contact lens wear affects tear film
evaporation. Eye Contact Lens. Nov 2008;34(6):326-330.
10. Nichols JJ, Sinnott LT. Tear film, contact lens, and patientrelated factors associated with contact lens-related dry eye.
Invest Ophthalmol Vis Sci. Apr 2006;47(4):1319-1328.
Bausch + Lomb Ultra is a trademark of Bausch & Lomb
Incorporated or its affiliates. All other brand/product names
are trademarks of their respective owners.
US/ZUS/14/0120
Average Predicted logMAR (±1 Standard Deviation)
0.7
samfilcon A
0.6
senofilcon A
lotrafilcon B
Predicted logMAR
0.5
comfilcon B
0.4
0.3
0.2
0.1
0.0
-0.1
Better
0
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
32
Elapsed Time (seconds)
Figure 4. Predicted logMAR as a function of time
42
■
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
w w w. c l s p e c t r u m . c o m
Don’t just meet
the needs of
your patients–
exceed them.
New Bausch + Lomb PeroxiClear™–
the most advanced* peroxide solution.
Delivers Exceptional Disinfection
Preservative Free
Provides Superior All-Day Comfort1,2*
Keep Lenses Cleaner and Moister for Longer1-5*
Lenses Are Ready to Wear in Only 4 Hours
PeroxiClear™
Clear Care
P
P
P
P
P
P
P
Switch your patients to the most advanced* peroxide solution.
Request your care kits today at Bausch.com/Peroxiclear.
*Compared to Clear Care
REFERENCES: 1. Results from a 22-investigator, multi-site study of PeroxiClear™, with a total of 440 eligible subjects. Subjects were randomized to use either PeroxiClear™ or Clear
Care for 3 months. Subjects completed performance surveys at 2-week, 1-month, 2-month, and 3-month visits. 2. Results from a 21-investigator, multi-site study of PeroxiClear™,
with a total of 297 eligible subjects who were habitual Clear Care users. After 7 days of use, subjects completed an online survey. Consumers rated the performance of PeroxiClear™
across a range of attributes and compared the performance to their habitual Clear Care solution. 3. High-resolution/accurate-mass (HR/AM) mass spectrometry was used to detect
and quantitate the relative amounts of surfactant retained on lenses from PeroxiClear™ and Clear Care solutions after 20 hours of wear. PureVision®2, ACUVUE OASYS, and AIR
OPTIX AQUA lenses were soaked in solutions for 12 hours prior to patients wearing lenses for 20 hours. 4. Results of an in vitro study measuring deposits on ACUVUE OASYS lenses.
Lenses were subjected to 14 cycles of deposition with a lipid and protein solution mimicking the human tear film followed by a cleaning regimen with either PeroxiClear™ or Clear
Care 3% hydrogen peroxide systems. Each deposition/cleaning cycle was representative of one day of patient use. Cycled lenses (n=3) were analyzed for deposits using image
analysis. After 14 cycles, lenses cleaned with PeroxiClear™ had only 8.0% surface coverage compared to 33.0% for lenses cleaned with Clear Care. 5. Results of an ex vivo study
measuring deposits on worn contact lenses to compare the clinical performance of PeroxiClear™ and Clear Care solutions. Lenses were worn daily for 1 month (silicone hydrogel and
Group IV hydrogel lenses) or 3 months (gas permeable lenses). A total of 374 lenses were randomly selected for image analysis. Lenses were scored for mean density of deposits
and percent coverage of deposits.
Distributed by Bausch + Lomb, a Division of Valeant Pharmaceuticals, North America LLC, Bridgewater, N.J.
PeroxiClear and PureVision are trademarks of Bausch & Lomb Incorporated or its affiliates.
All other brand/product names are trademarks of their respective owners.
©2014 Bausch & Lomb Incorporated. BLS07232 US/OCD/14/0002
PEROXIDE SOLUTIONS
A One-Step Hydrogen
Peroxide-based
Contact Lens Solution
Ms. Millard is a senior research scientist in Vision Care
at Bausch + Lomb, a division
of Valeant Pharmaceuticals.
She has more than 18 years
of experience in the medical
device and pharmaceutical
industries.
Dr. Hook is a Senior Principal
Scientist at Valeant and
Group Leader of the Structural and Surface Science Group
within Bausch + Lomb.
Dr. Hoteling is a Principal
Scientist with Bausch +
Lomb, a division of Valeant.
Dr. Wygladacz is a Senior
Research Scientist in Vision
Care R&D at Bausch + Lomb,
a division of Valeant.
44
■
Development of a cleaning and disinfecting
solution with a platinum-modulating compound.
By Kimberly A. Millard, MS; Daniel Hook, PhD;
Andrew Hoteling, PhD & Katarzyna Wygladacz, PhD
T
he concept of using
hydrogen peroxide to
disinfect contact lenses
was originally introduced in the early 1970s
(Aquavella, 1971). Subsequently, a
family of 3% hydrogen peroxide-based
lens care solution products were developed and commercialized. Currently,
peroxide solutions remain a significant part of the US soft contact lens
care solutions market and are used by
approximately 20% of contact lens
wearers (Nichols, 2014).
Hydrogen peroxide-based lens
cleaning and disinfecting systems need
to achieve adequate disinfection and
also reduce the 3% hydrogen peroxide
to residual levels that are safe for the
human corneal surface. For any 3%
hydrogen peroxide system, the residual
hydrogen peroxide concentration following neutralization must result in
minimal to no change in the cellular
structure or integrity of the corneal
epithelium and also must not elicit a
physiological response that may lead to
patient discomfort. Although the safety
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
threshold levels reported in the literature remain controversial, these values
typically range from 100 – 250 ppm
(Chalmers and McNally 1988, Paugh,
Brennan et al. 1988, Konynenbelt,
Mlnarik et al. 2011).
Two different types of peroxide lens
care systems have been introduced to
clean and disinfect soft contact lenses
and reduce the 3% hydrogen peroxide
to a safe residual level. They are classified as either one-step or two-step
contact lens disinfecting systems based
on the method used to neutralize the
hydrogen peroxide.
Two-step systems require a separate
neutralizing agent, typically a tablet,
which is added during the disinfection step and releases an enzyme such
as catalase. Hydrogen peroxide levels
remain at 3% until the catalase is released from the coated tablet and then
rapidly decrease to safe residual levels.
Two-step hydrogen peroxide systems
are generally considered very effective
at disinfection based on the initial high
peroxide concentration. However, it
has been shown that the catalase tab-
w w w. c l s p e c t r u m . c o m
lets may dissolve at different rates,
resulting in variable peroxide neutralization rates (Ngo et al, 2009).
The most popular of today’s
hydrogen peroxide-based contact
lens disinfecting systems contain 3% hydrogen peroxide in a
buffered solution and use only
one simple step to neutralize the hydrogen peroxide.
These one-step disinfecting systems catalyze neutralization of hydrogen peroxide via a process driven by a
platinum catalyst attached to the lens holder.
Although one-step systems are very simple to use,
most of the hydrogen peroxide is neutralized relatively
rapidly over the first 30-60 minutes (Nicolson et al,
1993; Millard, Xia et al, 2013). In effect, the amount
of hydrogen peroxide available to disinfect the lens
decreases quickly and a longer total disinfection/
neutralization time is needed to achieve the desired
anti-microbial efficacy. The advantage of the two-step
systems is that the neutralization of hydrogen peroxide may be delayed allowing enhanced anti-microbial
efficacy compared to one-step systems.
Typically, first generation one-step peroxide systems require a 6 hour regimen time in order to achieve
sufficiently low residual peroxide levels and adequate
disinfection efficacy. However, performance of a onestep disinfecting system could be significantly improved by controlling the rate of hydrogen peroxide
neutralization. In other words, delaying the neutralization of hydrogen peroxide should allow for higher total peroxide exposure, improving efficacy , and reducing microbial contamination (Penley et al, 1985). This
transient delay would ideally be followed by an accelerated neutralization phase resulting in a shorter total
regimen time offering both efficacy and convenience
to the user. A challenge for contact lens care formulators has been to develop a one-step system with a 3%
hydrogen peroxide solution with controlled neutralization in the initial phase of disinfection. Controlled
neutralization would enable excellent disinfection efficacy and result in residual peroxide levels that would
not cause ocular discomfort or physiological damage.
Ideally, a one-step peroxide solution with controlled
neutralization would also offer an additional advantage
of a shorter overall regimen time (Millard et al, 2013).
Platinum Modulating Compounds
Platinum modulating compounds (PMCs) are organic
molecules that typically consist of nitrogen, carbon,
and oxygen. Two examples are carbamide and thiourea
(Figure 1), which when added to a 3% hydrogen per-
w w w. c l s p e c t r u m . c o m
Figure 1. Chemical structures of the platinum modulating
compounds carbamide (A) and thiourea (B).
oxide solution may effectively control the neutralization process (Millard et al, 2013). Depending on the
compound properties, this interaction may be reversible or irreversible (Millard et al, 2013). PMCs have
the ability to slow peroxide neutralization during the
initial disinfection time (i.e., the first 30-60 minutes)
leaving a solution virtually free of viable organisms
while at the same time rendering residual peroxide
concentration levels that are non-irritating to ocular
tissues in only four hours (Millard et al, 2013).
The addition of a PMC to the peroxide disinfecting
solution modifies the neutralization profile of hydrogen peroxide, effectively increasing the amount of total peroxide exposure available to kill microorganisms.
The goal of incorporating a PMC is to increase the
total peroxide exposure while reducing the actual time
of disinfection, and thus allow for safe levels of residual
peroxide to be achieved in a shorter overall regimen.
Mechanism of Action
To further understand the mechanism of action of
PMCs and how they could be applied to develop a
next generation hydrogen-peroxide system, the interaction between peroxide neutralizing discs and
PMCs has been evaluated (Millard et al, ARVO, 2014).
Although many PMCs were screened (Millard et al,
GSLS, 2014), carbamide and thiourea were selected
for further study. These compounds are structural
analogues that differ only by one atom and yet their
neutralization profiles are distinctly different. Equimolar amounts of carbamide and thiourea were added
to 3% hydrogen peroxide solution and the neutralization profiles were measured. In addition, a solution of
3% hydrogen peroxide without the addition of a PMC
was used as a control. Figure 2 shows that the addition
of the PMCs significantly changed the neutralization
profile of the 3% peroxide solutions based on titration
measurements of hydrogen peroxide concentration.
Compared to the 3% peroxide control, carbamide delayed or initially slowed the neutralization while the
addition of an equimolar amount of thiourea resulted in virtually no peroxide neutralization even after
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
45
PEROXIDE SOLUTIONS
Figure 2. Neutralization profiles of 3% hydrogen peroxide
solution with addition of equimolar concentrations of
platinum modulating compounds (PMCs) and a neutralization profile recorded for a 3% peroxide control solution.
4 hours. These results clearly indicate the significant
impact on the peroxide neutralization profile when a
PMC is added to a 3% hydrogen peroxide solution
that is neutralized with a platinum coated disc. Additionally, careful selection and an optimized concentration of a given PMC allows the neutralization profile
to be controlled.
The neutralization profiles can be used to calculate
the total area under curve (AUC) to derive total peroxide exposure, expressed as ppm·hours. The calculated
total peroxide exposure values for 3% peroxide without
a PMC (control), 3% peroxide with carbamide, and 3%
peroxide with thirourea are shown in Table 1. These
values represent the total peroxide exposure available
to kill microorganisms during the targeted 4-hour neutralization time. At first glance, the control and carbamide neutralization profiles (Figure 2) look similar;
however, the total peroxide exposure value of 3% peroxide with carbamide is approximately twice that of the
control solution without a PMC.
T A B L E
1
Total hydrogen peroxide exposure (area under
curve) of test (3% peroxide with carbamide, and
3% peroxide with thiourea) and control (3% peroxide without a PMC) solutions.
PMC Compound
46
■
AUC (ppm-hrs)
Control
7730
Carbamide
16114
Thiourea
90334
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
To better understand the mechanism of action, the
interaction of carbamide and thiourea test solutions
with platinum discs was studied using two complementary surface sensitive analytical techniques; time
of flight secondary ion mass spectroscopy (ToF-SIMS)
and X-ray photoelectron spectroscopy (XPS). While
ToF-SIMS analysis provides qualitative information
and determines the structural constituents of a molecule, XPS was used to identify the elements present
on the surface and quantitate them.
Platinum discs were incubated overnight with
10 mL of 2% carbamide or thiourea in 20 mM phosphate buffer saline (PBS) solutions. The discs were
rinsed with purified water then carefully cut and
mounted for ToF-SIMS and XPS characterization.
The ToF-SIMS results definitively showed that
both carbamide and thiourea were present on the platinum disc surface. The images in Figure 3 show the
relatively uniform distributions of carbamide or thiourea observed on the platinum surface.
XPS analysis was used to quantitate the concentration of the detected elements distributed over the
surface of the platinum discs. Concentration of nitrogen, the element common for both PMCs, was used to
compare affinity of carbamide and thiourea to platinum substrates. The data is shown in Table 2. The calculated atomic concentration of nitrogen for the discs
exposed to thiourea buffered solution (N1s = 11.6 ±
2.1) was two times higher than the value calculated for
the discs soaked in carbamide buffered solution (N1s
= 5.8 ± 1.8). These results indicated stronger attraction of thiourea to the platinum discs and correlated
well with the differences in neutralization profiles displayed in Figure 2.
Additionally, the XPS results demonstrated a decrease in platinum concentration (Pt4f7) for the discs
incubated in any PMC solution (Pt4f7 = 19.6 ± 4.7
(carbamide), Pt4f7 = 14.2 ± 1.8 (thiourea), respectively) compared to the fresh platinum substrates (Pt4f7 =
25.3 ± 8.0). This indicates that the discs soaked either
with carbamide or thiourea were covered with PMC
compounds and therefore lower platinum concentrations were detected by XPS.
Coverage of the platinum discs with PMC components was of interest in these studies. Spatial distribution of the elements such as nitrogen and sulfur over
the platinum cut discs was examined by XPS mapping
(Figure 4). Concentration of the element of interest was displayed using a color-coded intensity scale.
While black indicated no particular element was detected, the areas of intensity that appeared yellowto-white corresponded to its highest concentration
w w w. c l s p e c t r u m . c o m
PEROXIDE SOLUTIONS
Figure 3. ToF-SIMS results for carbamide and thiourea
on the surface. XPS mapping performed for the discs
incubated in carbamide and thiourea showed uniform
distribution of PMCs over the platinum disc surfaces
and no evidence of PMC component aggregation was
detected.
of a second step. This PMC technology was incorporated into the development of a one-step peroxide
system — PeroxiClear cleaning and disinfection solution — which utilizes a combination of three different moisturizing agents to attract, spread and retain
moisture on the surface of the lens. Carbamide, one of
these three ingredients, serves a dual purpose as both
a natural moisturizing factor to help prevent dehydration, and as a platinum modulating compound.
The addition of a PMC in PeroxiClear solution
alters the typical peroxide neutralization profile compared to other peroxide contact lens cleaning and
disinfecting solutions. For example, in a comparison
of total peroxide exposure for PeroxiClear and Clear
Care (Alcon), the mean total AUC measurements
were calculated at 4 hours for PeroxiClear and 6 hours
for Clear Care. Both product systems were tested
four times and peroxide concentrations were plotted
to generate neutralization curves. As a result of the
slower initial neutralization produced by the PMC,
PeroxiClear had a statistically significantly higher total
peroxide exposure in 4 hours compared to Clear Care
after 6 hours (based on manufacturer recommended
disinfection times) (p<0.0001) (Figure 5).
In addition to total peroxide exposure, the mean
residual hydrogen peroxide concentration for
PeroxiClear 3% hydrogen peroxide system was also
tested. Ten lens cases were cycled one time with
10 mL aliquots of the solution and soaked for the recommended regimen time of 4 hours. Residual peroxide
Leveraging PMCs in
Novel Lens Care
Solution Development
The PMC interaction with
the platinum sites on the
neutralizing disc is new
technology that allows for
the controlled neutralization of a 3% peroxide solution. PMCs help one-step
peroxide systems mimic the
slow initial neutralization of
a two-step peroxide system
without the inconvenience
Figure 4. Spatial distribution
of nitrogen (N1s) and sulfur
(S2p) over exemplary platinum (Pt4f7) cut discs exposed
to carbamide and thiourea
buffered solutions.
w w w. c l s p e c t r u m . c o m
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T O N 2 0 1 4 ■
47
PEROXIDE SOLUTIONS
ture, pH and osmolality within the case during the
first 60 minutes of neutralization. This is evidenced
by the results of timed evaluations of temperature,
pH and osmolality during the neutralization process.
Within the first 0-60 minutes of neutralization, the
temperature of the carbamide test solution increases,
the pH increases and the osmolality decreases rapidly.
Conclusion
Figure 5. Total peroxide exposure during the
manufacturers’ recommended disinfecting time for
PeroxiClear (4 hours) and Clear Care (6 hours).
concentrations were measured using redox titration
with a Mettler Toledo T50 Auto-Titrator. The mean
residual peroxide level for PeroxiClear solution after
4 hours was 64.8 ± 12.3 ppm, well below thresholds
for ocular detection or cellular changes (Chalmers et
al, 1988; Paugh et al, 1988; Konynenbelt et al, 2011).
Physico-Chemical Changes
When XPS elemental composition data was used to
quantitate the relative amounts of carbamide adsorbed
to the platinum sites during the neutralization process
for PeroxiClear at 0, 5, 15, 30 and 60 minutes, an increase in the carbamide detected on the platinum sites
on the coated disc surface was evident from 0-30 minutes. At 60 minutes, the atomic coverage (%) decreased.
The loss in affinity of carbamide for the platinum
surface after 60 minutes may be attributed to the simultaneous physico-chemical changes in temperaT A B L E
2
Atomic Concentration (%) – average values – calculated for nitrogen (N1s) and sulfur (S2p) detected
by XPS on the surface of the platinum (Pt4f7) discs
exposed to carbamide and thiourea buffered solutions. The data were calculated for n = 20.
PMC
Compound
Nitrogen
(N1s)
Sulfur
(S2p)
Platinum
(Pt4f7)
N/A
N/A
25.3 ± 8.0
Carbamide
5.8 ± 1.8
N/A
19.6 ± 4.7
Thiourea
11.6 ± 2.1
4.7 ± 0.7
14.2 ± 1.8
Control*
48
■
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
Combination of a suitable PMC such as carbamide with 3% hydrogen peroxide was shown
to be a breakthrough approach that may improve the performance of peroxide-based lens care
solutions. Application of this technology in
PeroxiClear cleaning and disinfecting solution allowed
for a higher total hydrogen peroxide exposure, in only
4 hours, and residual peroxide levels that are nonirritating to ocular tissues. CLS
References
1. Aquavella JV, GK Jackson, Guy LF. Bionite hydrophilic
contact lenses used as cosmetic devices. Am J Ophthalmol
1971;72(3):527-531.
2. Nichols JJ. Annual Report: Contact Lenses 2013. Contact Lens
Spectrum; January 2014.
3. Chalmers RL, McNally JJ. Ocular detection threshold for hydrogen peroxide: Drops vs. Lenses. ICLC 1988;15(11):351-357.
4. Paugh JR, Brennan NA, Efron N. Ocular response to hydrogen
peroxide. Am J Optom Physiol Opt 1988;65(2):91-98.
5. Konynenbelt, B. J., D. S. Mlnarik and J. L. Ubels. Effects of
peroxide-based contact lens-disinfecting systems on human
corneal epithelial cells in vitro. Eye Contact Lens 2001;37(5):
286-297.
6. Ngo W, Heynen M, Joyce E, Jones L. Impact of protein and
lipid on neutralization times of hydrogen peroxide care regimens. Eye Contact Lens 2009;35(6):282-286.
7. Nicolson P, Seamons KR, Tsao F, Alvord LA, McCraw EC,
Inventors. Peroxide Disinfection Method. US patent 5,306,352;
1993.
8. Millard KA, Xia E, Groemminger S, Kilbury J. Peroxide Lens
Care Solution. U.S. Patent Application 13/835237, filed March
15, 2013. Pub. No.: US 2013/0209313.
9. Penley CA, Llabres C, Wilson LA, Ahearn DG. Efficacy of
hydrogen peroxide disinfection systems for soft contact lenses
contaminated with fungi. CLAO J 1985;11(1):65-68.
10. Millard KA, Groemminger S, Hoteling A, Hook D, Wygladacz KA. Surface Characterization of the Interaction Between
Peroxide Neutralizing Disks and Platinum Modulating Compounds. ARVO 2014. Orlando, Florida.
11. Millard KA, Groemminger S, Xia E, Kilbury J. Evaluation of
Platinum Modulating Compounds to Delay the Neutralization of Hydrogen Peroxide in One-Step Disinfecting Systems.
Global Specialty Lens Symposium 2014. Las Vegas.
PeroxiClear is a trademark of Bausch & Lomb Incorporated or its affiliates. All other brand/product names are trademarks of their respective
owners.
US/OCD/14/0054
w w w. c l s p e c t r u m . c o m
PATIENT REL ATIONS
Growing My Practice
With a Novel Contact
Lens Technology
Even when patients say, “I’m happy with the lens I have.”
By Matthew Ward, OD
S
Dr. Ward is an optometrist
with Eye Care of Iowa, a
five-location private practice
in central Iowa. His interests
include dry eye and ocular
nutrition. He has received
honoraria in the past year for
speaking and writing from
B+L and TearScience. You can
reach him at eyedocward@
gmail.com.
w w w. c l s p e c t r u m . c o m
ilicone hydrogels were
first introduced in the
late 1990s. The goal was a
healthier contact lens when
compared to the low Dk
hydrogel materials available at the
time to improve oxygen transmission
to the eye. While we’ve seen a decrease in conditions such as corneal
edema, microcysts and neovascularization, and a reduction in limbal redness
(Fonn et al, 2006), the most common
complaint I hear from patients is about
contact lens-associated dryness. This
isn’t news to any of us. With research
indicating current contact lens dropout of 10 to 20% annually (Rumpakis,
2010), we have yet to address the issue
of dryness. The digital age of constant
computer and smart phone use doesn’t
help the matter. With a 65% decrease
in blink rate with sustained visual tasks
(Patel et al, 1991), contact lens patients
may experience daily grittiness and irritation to a greater extent than we are
possibly aware.
In my practice, I like to offer my
patients a healthy contact lens with
exceptional comfort and optics in one
package. Over the past few years, we’ve
been fortunate to have new materials
introduced for daily disposable use,
monthly use, and even new cosmetic
lenses. How do my staff and I engage
in a discussion about new contact lens
technology in a presumed-satisfied
contact lens wearer who walks in after
18 months for a prescription renewal?
Asking the Right Questions
Does this sound familiar? You enter the
room to see your next contact lens patient. You drop into the chair, smile at
the patient, and welcome him to your
office. You thank him for choosing to
come to you for his eye care. One of
the first questions you ask is “So how
are your contact lenses?” The patient
reports they are “fine.” That may seem
sufficient at first thought. If patients
truly had problems, they would tell us,
right? Studies indicate that as many as
2 out of 3 patients don’t discuss contact
lens issues they may be having with
their eye care practitioner (Kadence
survey, 2012). Why is this? Are they
afraid we’ll tell them they can no longer wear contact lenses if they say they
experience contact lens discomfort,
or their eyes feel dry or they struggle
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
49
PATIENT REL ATIONS
with their vision through the day? And what impact
does this unrecognized or hidden dissatisfaction have
on the risk for contact lens dropout?
Taking the time to ask
open-ended questions may
lead to a more successful
contact lens patient, which
in turn could increase the
patient’s loyalty to you and
your practice.
For example, asking a patient about their endof-day comfort can frequently result in a patient response of “they’re fine.” We could leave it at that and
let muscle memory take over. We could reach for the
same box of lenses the patient has been wearing and
send him off with a prescription or usually something
less than an annual contact lens supply, with the hope
that he’ll return for an eye exam in 12 to 18 months.
But is this patient truly happy and satisfied with contact lens wear? Have we done our due diligence in
assessing patient satisfaction?
Fitting contact lenses is a routine/repetitive part of
practice for most of us, a routine that we don’t even
think about most of the time. It’s become a habit, and
habits (good or bad) are very hard to change. In fact,
fitting contact lenses is such a strong habit that many
of us can do it without even ‘actively’ thinking about
it (like when you end up in your drive way and can’t
quite remember all the things that you encounter on
the way home). Once habits are established, they actually involve less thinking or engagement on our part.
All of us have habits, including many good ones. The
key is to recognize a habit loop and what the cues are
which trigger them (Duhigg, 2014) in order to understand how we can change them for the betterment of
our patient’s contact lens-wearing experience and our
practice profitability. One of the simplest habit changes we’ve employed where I practice is to ask more detailed questions about each patient’s contact lens experience. For example, “Do your lenses feel just as good
in the evening as they do in the morning? Do you find
your vision fluctuating throughout the day? Do you
find yourself blinking or rubbing at your eyes to try
to clear up your vision?” Taking an extra 30 seconds
to ask these questions (or have your staff ask during a
50
■
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
patient work-up) can better elicit any issues the patient may be having, that our routine questions may
not be able to uncover. This gives us an incredible opportunity to introduce new technology and improve
patient satisfaction. The patient will appreciate our
practice more and also be more likely to remain in
contact lens wear. Taking the time to ask open-ended
questions may lead to a more successful contact lens
patient, which in turn could increase the patient’s loyalty to you and your practice.
Another habit I’ve tried to change in my practice is
related to asking patients how many boxes of contact
lenses they would like to purchase at the end of a visit.
This habit is the reason why so many of our patients
typically used to order only one or two boxes. We
know this leads to the risk of non-compliance (using
the contact lenses longer than recommended) or ordering contact lenses online or from another provider.
In my practice, I prefer to recommend monthly replacement lenses and my newly established habit is to
assume that a patient wants an annual supply of lenses from our office. We no longer ask patients “How
many?” Instead we say, “The doctor has approved an
annual supply.” This, in addition to competitive pricing and rebate programs, helps to keep patient contact
lens purchases in our practice.
In my practice, I’ve implemented a change in many
of the habits we’ve developed in how my staff and I
interact with contact lens patients and I can see the
return on the investment in a better relationship with
my patient and more patients choosing to get their
annual supply of contact lenses from my office versus
shopping around.
The Next Best Thing
I pride myself on offering the newest and greatest in
contact lens technology, particularly for patients who
may be experiencing dissatisfaction associated with
dryness symptoms or discomfort with their current
contact lenses. But it’s up to us, the eye care professionals, to uncover the underlying dissatisfaction before it
leads to a patient discontinuing contact lens wear.
As I become more familiar with a new lens technology, I typically start to recommend this new technology to all patients, even those who don’t have outright
complaints of discomfort. Imagine that. Taking a patient with zero complaints, 20/20 vision and a white
healthy eye, and offering him something new. Waste
of time? No way. Although a patient may not have
an overt complaint, he may not recognize that there
could be a higher benchmark for comfort or vision.
I’ll ask my patient, “Would you like to have more
w w w. c l s p e c t r u m . c o m
PATIENT REL ATIONS
Although a patient may
not have an overt
complaint, he may not
recognize that there could
be a higher benchmark
for comfort or vision.
ing to be a long-term option for them because of ongoing discomfort or vision issues, we’re finding great
success in fitting new contact lens options coming on
the market. CLS
References
1. Fonn D, Dumbleton K, Jailber I, Sivak A. Benefits of Silicon Hydrogel Lenses. Contact Lens Spectrum. http://www.
clspectrum.com/articleviewer.aspx?articleid=12955. Published
February 1, 2006.
2. Rumpakis J. New Data on Contact Lens Dropouts: An International Perspective. Rev Optometry. http://www.revoptom.com/
content/d/contact_lenses_and_solutions/c/18929/. Published
comfortable, consistent vision throughout the day?
January 15, 2010.
Would you like a contact lens that dehydrates more
3. Patel S, Henderson R, Bradley L, Galloway B, Hunter L. Effect
slowly, such as when you work on the computer?
of visual display unit use on blink rate and tear stability. Optom
Vis Sci. 1991 Nov;68(11):888-92.
Summary
4. Exploring Comfort and Vision Survey - Kadence International,
2012. Phase 1: A total of 568 contact lens wearers (136 daily disNovel contact lens technology now provides patients
posable, 432 planned replacement) completed an online survey
with an exceptionally healthy contact lens, providing
regarding comfort and vision symptoms associated with contact
comfortable and great vision throughout a full day of
lens wear. Phase 2: A random subset of 287 contact lens wearers
(78 daily disposable, 209 planned replacement) were then asked
wear. More and more patients are returning to my ofto track vision and comfort symptoms and complete a second
fice stating that while they thought their old lenses
online survey
were “comfortable,” this new lens brings “comfort” to
5. Duhigg C. The Power of Habit: Random House Trade Papera whole new level. Where some of my patients may
backs; 2014.
to think that contact
lensHouse
wear Ad.qxd
was not goUS/ZUS/14/0125
CLS have
Web come
Half Hor.qxd:CLS
Web Site
7/20/10 4:29 PM Page 1
Searching for information
on a specific topic?
Find it quickly and easily on the
Contact Lens Spectrum website.
Searchable Article Archives
This Month’s Features
Breaking News
Upcoming Events/Seminars
Contact Lenses Today E-newsletter Archive
Subscription Information
Annual Contact Lenses & Solutions Summary
Links to Contact Lens Manufacturer
Websites
www.clspectrum.com
An interactive extension of the leading clinical contact lens information source.
Contact Lens Practice Pearls
B
Y
J
A
S
O
N
R
.
M
I
L
L
E
R
,
O
D
,
M
B
A
,
F
A
A
O
The Contact Lens Conversation
I
n the changing face of health care, contact
lenses are vitally important to most eyecare practices. Advanced contact lens materials, designs
and solution systems have improved our ability to
provide a comfortable contact
lens-wearing experience, but we
need to better utilize new technology and work to understand
our patients’ concerns and comfort issues so we can keep them
comfortable in their lenses. All of
this starts with asking the right
questions.
How do you talk to your patients about the comfort of their
contact lenses?
• Is it a quick, “how are you
doing with your contact lenses?
Good? Then I’ll renew the contact lens Rx with the same lenses.”
• A little more involved, “Do
your lenses feel comfortable?”
• Or is it a full press, “Do your
contact lenses feel as comfortable
at the end of the day as at the
beginning? Are they equally comfortable at the beginning of the
wear cycle compared to the end
of the wear cycle? When using a
computer, do you experience any
intermittent blur? Do you work
outdoors and if so, do you use eye
drops during the day to help with
comfort?”
In addition, how are comfort
questions asked?
• Via a paper questionnaire?
• By staff during the history?
• Or do you ask patients?
Address the Issue
Contact lens comfort needs to be
52
■
at the forefront, because the statistics are staggering — a single
dropout could cost $275 in lost
annual revenue, and this doesn’t
include the future value of treating the patient and potential referrals (Rumpakis 2010). As a vast
majority of contact lens dropouts
are due to discomfort (Nichols
et al, 2005; Guillon and Maissa,
2005), exploring ways to improve
comfort must be at the heart of
your efforts.
Look for It
A careful corneal evaluation can
identify potential complications
along with specific treatment
regimens for contact lens candidates. A detailed corneal assessment before, during and after the
initiation of contact lens wear —
is essential to preventing contact
lens dropouts.
This is a great time to ask
about comfort. Ask when you’re
behind the slit lamp and you may
be surprised what you hear.
Silent Dropouts
Don’t assume your patients are
wearing their contact lenses comfortably; they may have silently
dropped out of contact lens wear
without your knowledge.
To prevent or identify these
silent dropouts, consider asking
or having your staff ask these core
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
questions.
• Rate your comfort from 1 to
10 upon contact lens insertion
• Rate your comfort from 1 to
10 at the end of the day
• How many hours do you
wear your lenses per day and
would you like to be able to wear
them longer?
• Rate your vision while at the
computer
Then, you follow-up with
more probing questions from
behind the slit lamp;
For example, you could say
“Comfort is a priority in my
office. Is there anything you
would like to see improved with
your current lenses or the wearing schedule?
If there are concerns, address
them and offer alternatives. If
comfort truly is a focus within
your contact lens practice, a protocol for these questions should
be developed and used at every
encounter. We all want our patients to feel as comfortable as
possible in their contact lenses.
When we continue to offer the
newest innovations
in contact
lens materials, modalities and care
products, we can be confident
we’re giving our patients their
highest chance for success. CLS
For references, please visit www.
clspectrum.com/references.asp and
click on document #SE2014.
Dr. Miller is in a partnership private practice in
Powell, Ohio, and is an adjunct faculty member
for The Ohio State University College of Optometry. He has received honoraria for writing,
speaking, acting in an advisory capacity, or
research from Alcon, Allergan, CooperVision,
and Visioneering Technologies. You can reach
him at [email protected].
w w w. c l s p e c t r u m . c o m
The Business of Contact Lenses
B
Y
G
A
R
Y
G
E
R
B
E
R
,
O
D
Assessing the Value of Adding
New Technology
M
aking a decision about whether to bring a new product or technology into your practice isn’t always
as straightforward as it may seem. On the clinical
side, the decision is relatively easy, especially for
new products. For example, if a
new contact lens is clinically
superior, and you’re committed
to providing the best care to your
patients, the decision is already
made. This assumes you have a
practice mission that includes
this sentiment about patient
care. This goes to the difference
between simply saying you’ll do
something vs. actually doing it. In
this case, if your practice is about
providing the best — provide it.
Of course, “new” doesn’t
always equal “best.” But since it
often does, it behooves you to at
least try new products so you can
decide for yourself. Waiting until
others have tried something new
isn’t necessarily bad, but there can
be significant marketing benefits
to being a “first mover.”
Because of the cost, it’s often
more challenging to introduce
new technology (versus products)
into your practice. Fitting a new
contact lens may involve little or
no investment, but that’s often
not the case with technology.
Usage and ROI
The biggest wildcard for most
practices is anticipated usage. If
you lease something, it’s easy to
calculate how many times per
w w w. c l s p e c t r u m . c o m
month you’ll need to use the
device to cover the cost of the
lease. Of course, using new technology to break even is a poor
business strategy so it’s better
to build in the desired amount
of profit you’d like each month
and use that to evaluate ROI and
guide your decision. Some of the
profit may come directly from the
device and some of it may come
indirectly from it. For example, if
it’s used to help diagnose dry eye,
you may find added revenue in
the extra office visits and products
you sell for dry eye.
Volume
Anticipated volume predictions
are easy. Just make a list of how
many times in a month you would
have used the new technology, if
you had it. Then, you can determine if the new equipment is a
fiscally sound purchase. Remember to consider any incremental
profit you’d make from additional
visits or sales of products.
So for example, if the widget
payment is $1,000 per month
and you plan on charging (and
collecting) $50 from each test
you run and selling $50 worth of
related products, and you want
to make $1,000 a month profit,
you’ll need to use the widget 20
times per month and sell products
to all 20 patients.
Gauging Patient Interest
To use this model, you have to
know what you’ll charge and have
a good sense of your patients’
willingness to move forward with
recommended tests or treatments.
That part is as easy as asking,
“Mrs. Dry Eye, we’re considering
adding some new technology to
the office. It helps to better diagnose your dry eyes and it works
by . . . The charge for the test is
$XX and it is (or isn’t) covered
by your insurance. If we were to
bring it into the office, how likely
would you be to have the test
done?”
Patients who express an interest should be kept on a list and
notified as soon as you’re trained
on the new equipment. Depending what you buy, what it costs
and your patients’ interest, you
might consider paying cash versus
financing if enough patients are
on your list.
Assess Before You Invest
If you assess anticipated usage
and ROI, along with volume and
patient interest, you should have a
pretty good idea if it makes sense
to move forward with a particular
piece of new technology. CLS
Dr. Gerber is the president of the Power Practice, a company offering proven and comprehensive practice and profit building systems.
You can reach him at www.PowerPractice.com
and follow him on Twitter @PowerYourDream.
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
53
Pediatric and Teen CL Care
B
Y
J
E
F
F
R
E
Y
J
.
W
A
L
L
I
N
E
,
O
D
,
P
H
D
,
F
A
A
O
Myopia Control Consent Form
A
burgeoning area of contact lens innovation is
myopia control. While there are several brands
believed to slow myopic growth of the eye, none
are approved by the FDA for the purpose of
myopia control. Although contact
lenses currently used off label for
myopia control are approved for
wear without age restriction, the
FDA is requiring data on safety as
well as efficacy for pediatric contact lens wear with a myopia control indication. Because cases of
microbial keratitis or corneal infiltrative events are rare, examining
the safety of contact lens wear in
children requires an exceedingly
large, long-term study. Therefore,
FDA approval for myopia control
is not expected any time soon and
lenses used as such are done so in
an off-label manner.
In light of that fact, practitioners should not advertise myopia
control with a particular brand
or even modality of contact lens.
Furthermore, parents must be
made aware that the contact
lenses are not approved by the
FDA for myopia control. It can
be stated that they are approved
for wear by children, but not to
slow the progression of nearsightedness in children. Acknowledgment by the parent that the con-
TA B L E 1
Sample Consent Form Information
tact lenses are not FDA approved
for this use is important, so an
informed consent document is
important. The document should
clearly state that the lenses are
not FDA approved for myopia
control, provide a general statement of risk regarding contact
lens wear, and indicate the
evidence for myopia control.
Figure 1 shows information from
the informed consent document
used at the Kids Contact Lens
Clinic at The Ohio State University College of Optometry. CLS
Dr. Walline is an associate professor at The
Ohio State University College of Optometry.
His research interests primarily involve pediatric contact lenses and myopia control. He
has received research funding from Johnson
& Johnson Vision Care. You can reach him at
[email protected].
We insist that parents of patients opting for any of these off-label treatments must sign a form to indicate consent
before we will start treatment. Here is some of the information we would include on that form.
Corneal Reshaping–Corneal reshaping contact lenses are worn during sleep and removed in the morning. They temporarily change the shape of the cornea (the clear window on the front of the eye), so that the child can see clearly
all day long without glasses or contact lenses. During the first two weeks of wear, your child will experience changing
vision. When the vision gets worse, he may put on glasses to provide clear vision. Although the chance of an eye infection is still very low (about one case per 500 years of wear), it is greater for corneal reshaping contact lenses than
usual daytime contact lens wear because the contact lens is worn overnight.
Soft Bifocal–Soft bifocal contact lenses are routinely worn to help people over 40 years of age read clearly as well
as see far away. Children may not see quite as clearly with these contact lenses as other types of contact lenses, but
there are no additional risks compared to regular daily contact lens wear.
Atropine–Atropine is an eye drop that typically makes light seem bright because it makes the pupil (black hole in
the middle of the eye) bigger, and it blurs near vision because it reduces the ability to focus the eyes while looking
at near. Low concentration (0.01%) atropine has been shown to slow the progression of nearsightedness by 61%
without increasing pupil size or decreasing near vision dramatically. Only 8% of children complained of problems
with low concentration atropine, and glasses can reduce symptoms if your child notices poor reading vision or
lights seem too bright.
54
■
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
w w w. c l s p e c t r u m . c o m
Treatment Plan
B
Y
W
I
L
L
I
A
M
L
.
M
I
L
L
E
R
,
O
D
,
P
H
D
,
F
A
A
O
Learnings from the Contact
Lens Discomfort Workshop
A
s with the Dry Eye WorkShop (DEWS) report
and the International Workshop on Meibomian
Gland Dysfunction (MGD) before it, the Contact Lens Discomfort Workshop has established
a foundation of what is known
and unknown in an important dilemma interfering with successful
contact lens wear in our patients.
The recently published report
exhaustively covers all aspects
related to contact lens-related
discomfort (TFOS 2013).
One report within the comprehensive workshop covers the
treatment and management of
the condition and discusses what
evidence-based medicine exists
for particular therapies. Level I
evidence would be that which is
conducted using carefully controlled randomized clinical trials.
Level II evidence could come
TA B LE 1
Areas often addressed by
an ECP when managing
Contact Lens Discomfort
Replacement frequency
Material change
Parameter change
Wetting agents
Contact lens care system
Tear supplements
Environment
Nutrition
Punctal occlusion
Topical medication
w w w. c l s p e c t r u m . c o m
from well-designed non-randomized trials. While the lowest form
of evidence would be related to
case reports, descriptive reports,
expert opinions and the like. Anecdotal or personal preference
modes of treatment, although important, would not be considered
to rise to the level of scientific
rigor often considered.
Table 1 illustrates areas often
chosen by eyecare practitioners
to address when trying to solve
contact lens discomfort (CLD) in
their patients. This column will
succinctly address the evidence to
date regarding each category.
Initial Considerations:
Replacement Schedule,
Materials and Parameters
Replacement frequency, material and parameter changes are
often among the first areas addressed when treating contact
lens discomfort. The evidence to
date (Level II), suggests that daily
disposable contact lenses could be
one way to address the discomfort
problem. This may be related to
the elimination of a contact lens
care system. Practitioners also
have distinct opinions regarding material choices to address
CLD. On the surface, it appears
as though switching to a silicone
hydrogel lens may be mildly helpful in improving comfort. However, studies for both hydrogel
and silicone hydrogel exist that
demonstrate the effectiveness
of each. The issue is related to
methodologies employed by each
that tend to decrease the level
of evidence for individual outcomes. Parameter changes more
favorable to promoting comfort
include contact lens edges with a
knife profile, steeper base curves
and larger overall diameter lenses.
The practical problem with each
of these parameter changes is that
typically, unless custom-made
lenses are ordered, a practitioner
is unable to change any of these
parameters in isolation.
Wetting Agents
Contact lenses with intrinsic
(material laden) or extrinsic
(blister pack) wetting agents are
another factor used to solve CLD.
No evidence exists for the use of
intrinsic wetting agents in enhancing comfort. However, Level
II and III evidence exists showing
that extrinsic wetting agents do
increase comfortable wear, albeit
short-lived in many cases.
Care Systems
Level II evidence suggests that
contact lens care system choices
favor matching them with individual contact lenses types, even
if the manufacturers of each are
disparate. Level I evidence is
conflicted with regards to particu-
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4 ■
55
Treatment Plan
Prescribing
for Presbyopia
lar contact lens care system recommendations to decrease CLD.
Tear Supplements
Once contact lenses and care
systems are addressed by the
ECP, the next most commonly
performed intervention to address CLD involves topically
applied tear supplements to the
contact lens and ocular surface.
Most consider this the mainstay
of therapy for mild to moderate
degrees of CLD. Most evidence,
Level II and III, concludes that
this therapy is beneficial to improving CLD. Earlier studies
indicate that even 0.9% saline
could be helpful. More recent
studies favor complex tear supplements that may include polyvinyl
alcohol (PVA), carboxymethylcellulose (CMC) and Povidone.
There is also evidence (Level II)
that hydroxyl propyl cellulose
(Lacrisert) inserts are helpful in
improving comfort with contact
lenses at least to 1 month.
Environmental Considerations
Environmental interventions,
though intuitive, have little basis
in published literature. Some level III studies indicate that smoke,
pollen, dust and low humidity
should be avoided to improve
comfort. Blinking behavior modification to improve comfort has
not been proven in the literature.
Nutritional Supplements
Nutritional interventions, although part of clearly proven
non-contact lens dry eye therapy,
finds little evidence for combatting CLD. One Level I study
showed that the use of Omega-6
improved comfort in contact lens
wearers, however the study was
only conducted on a cohort of
56
■
female subjects. Evidential support of improving hydration levels to treat CLD is currently not
supported by the literature.
Punctal Occlusion
The evidence supports the use
of punctal occlusion to improve
comfort. The occlusion should
be performed with silicone plugs
and both the inferior and superior
puncta should be occluded.
Steroids and NSAIDs
No studies exist for demonstrating the use of steroids and nonsteroidal anti-inflammatories
for use with soft contact lens
discomfort. Although Level II
evidence shows that diclofenac
improves comfort in RGP contact
lens wearers in the early adaptation period. One Level I study,
albeit open label, demonstrated
the effectiveness of azithromycin
(bid) for 1 month in improving
comfort in contact lens wearers.
Future research involves medications that focus on neuromodulators such as resiniferatoxin, which
target nociceptive neurons and
modulate the pain response.
(Continued from page 11)
adjust to simultaneous multifocal
optics more easily.
A recent study exploring patient performance with multifocal
and monovision correction found
Consider light level
when assessing
multifocal contact
lens performance
on presbyopes of
all ages.
acuity with multifocals, both at
distance and near, improved over
a 15-day period (Fernandes et al,
2013). This suggests a possible
adaptation of the visual system to
multifocal optics over time. Interestingly, this same study found
acuity with monovision did not
improve. In fact, visual performance appeared to decrease over
time in some cases.
Stay Current
In conclusion, I encourage you to
consult the full report to garner
specific details, study references
and results for each category. CLS
For references, please visit www.
clspectrum.com/references.asp and
click on document #SE2014.
Staying abreast of current literature on multifocal contact lenses
provides insight into why these
lenses sometimes don’t perform
as we’d expect. It also arms us
with strategies to help deliver
improved performance. CLS
For references, please visit www.
clspectrum.com/references and click
on document #SE2014.
Dr. Miller is an associate professor and chair of
the Clinical Sciences Department at the University of Houston College of Optometry. He is a
member of the American Academy of Optometry and the AOA where he serves on its Journal
Review Board. He is a consultant or advisor to
Alcon and Vistakon and has received research
funding from Alcon and CooperVision and lecture or authorship honoraria from Alcon and
B+L. You can reach him at [email protected].
Dr. Quinn is in group practice in Athens, Ohio.
He is an advisor to the GP Lens Institute and
an area manager for Vision Source. He is an
advisor or consultant to Alcon and B+L, has
received research funding from Alcon, AMO,
Allergan, and B+L, and has received lecture
or authorship honoraria from Alcon, B+L,
CooperVision, GPLI, SynergEyes, and STAPLE
program. You can reach him at tgquinn5@
gmail.com.
Check out the Report
C O N TA C T L E N S S P E C T R U M / S P E C I A L E D I T I O N 2 0 1 4
w w w. c l s p e c t r u m . c o m
Searching near, far, and everywhere in
between for great multifocal contact lenses?
PureVision 2 Multi-Focal contact lenses
For Presbyopia
®
For clarity where it counts — in the real world.
Distributed by Bausch + Lomb, a Division of Valeant Pharmaceuticals North America LLC, Bridgewater, N.J. © 2014 Bausch & Lomb Incorporated.
PureVision is a trademark of Bausch & Lomb Incorporated or its affiliates. PNS07256 US/PVP/14/0029
Discover
Biotrue ONEday
®
Lenses
Made from HyperGel™, a bio-inspired
material designed to work like the eye
Meets
Matches
Mimics
oxygen level the
open eye needs1
water content of
the cornea — 78%2
lipid layer of the
tear film3
Now
Available
Biotrue® ONEday
for Presbyopia
Recommend comfortable
vision throughout the day
with Biotrue ONEday and
Biotrue ONEday for Presbyopia.
For more information, call 1-800-828-9030, contact your Sales Representative or visit biotrue.com
Distributed by Bausch + Lomb, a Division of Valeant Pharmaceuticals, North America LLC, Bridgewater, N.J. © 2014 Bausch & Lomb Incorporated. ®/™ are trademarks of Bausch & Lomb Incorporated or its affiliates.
PNS07134 US/BPR/14/0013
REFERENCES: 1. Brennan NA. A Model of Oxygen Flux Through Contact Lenses, Cornea 20(1):104-108, 2001. 2. Bergmanson J. Clinical Ocular
Anatomy and Physiology. 14th ed. Houston, Texas: Texas Eye Research and Technology Center; 2007. 3. Twenty-two subjects participated in
a randomized, double-masked, contralateral eye study to evaluate water loss of Biotrue® ONEday, 1-Day ACUVUE MOIST, and 1-Day ACUVUE
TruEye. After 4, 8, 12, and 16 hours of wear, lenses were removed and immediately weighed (wet weight). The lenses were then completely
dried and reweighed (dry weight). The percent water loss was then calculated for each lens from the wet and dry weights.