Download PDF Edition - Review of Cornea and Contact Lenses

NOVEMBER 2016
RCCL
REVIEW OF CORNEA
& CONTACT LENSES
TARGETING
Astigmatism
The Toric
Toolbox P. 08
Taking Torics
to the Top P. 10
Sclerals for Irregular
Corneas P. 14
EARN 1 CE CREDIT
Surgical Correction of
Astigmatism P. 18
Supplement to
Tear Film Dynamics
•
Scleral-induced Pingueculitis
•
Breaking Bad Habits
•
Building Your Practice
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©2016 CooperVision 9033O BC 7/16
RCCL0916_Coopervision Biofinity.indd 1
8/29/16 11:01 AM
contents
Review of Cornea & Contact Lenses | November 2016
departments
4
News Review
Corneal Thickness May Help Predict
CXL Outcomes; New Stats Highlight
the Need for More DED Education
6
My Perspective
A Look at the Androgen Connection
By Joseph P. Shovlin, OD
8
The GP Experts
The Toric Toolbox: Don’t Forget GPs
By Robert Ensley, OD, and
Heidi Miller, OD
32
Practice Progress
Breaking Habits
By Mile Brujic, OD, and
Jason R. Miller, OD, MBA
34
Out of the Box
features
10
14
18
Four Keys to Building Your Practice
By Gary Gerber, OD
Taking Torics to the Top
Fitting toric lenses has become
increasingly straightforward and now
presents a viable option for myriad
contact lens wearers.
By David Kading, OD, and
Charissa Young, OD
When to Opt for
Scleral Lenses
Irregular cornea patients in particular can
enjoy the many benefits that accompany
fitting scleral lenses.
By Michael J. Lipson, OD
CE — Surgical Options for the
Correction of Astigmatism
Today’s
sophisticated
surgical tools
and techniques
offer dramatically
improved outcomes
over the imprecise
early efforts of
yesterday.
By Kristen Brown, OD
24
29
Become a Fan on
Facebook
/ReviewofCorneaAndContactLenses
Case Report:
Solving Scleral Contact
Lens-Induced Pingueculitis
The simplest option is often the best
solution.
By Brian Chou, OD
Advances in Understanding
Tear Film Dynamics
Let’s gain some perspective on
the components, modalities, and
methodology of dry eye.
By Will Smith, OD
Follow Us On
Twitter
@RCCLmag
REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
3
News Review
IN BRIEF
■ Dry eye symptoms and body fat may
be correlated, a new prospective study
suggests. Researchers sampled ocular
symptoms and indices of adiposity in the
general adult population and in the 305
participants, including 53 contact lens
wearers. Results show a moderate correlation between body fat percentage
and dry eye symptoms. Chronic inflammation may be the link. “Adipose tissue
contributes to a rise in circulating levels
of many proinflammatory mediators,” the
researchers state.
Ho KC, Jalbert I, Watt K, Golebiowski B. A
possible association between dry eye symptoms
and body fat: a prospective, cross-sectional preliminary study. Eye & Contact Lens. 2016. EPub
ahead of print.
■ Keratitis infections appear to be more
common in the summer, according to
a new study. Researchers performed a
retrospective chart review on patients
presenting to the emergency department
who were diagnosed with infectious
keratitis from 2008 to 2013. Looking at
data from 155 patients diagnosed with
keratitis, researchers found that 12.3% of
patients with ulcers presented in the fall,
21.3% in the spring, 21.9% in the winter
and 44.5% in the summer—indicating a
higher frequency of infectious keratitis
and P. aeruginosa positivity during the
summer months. Researchers posit that
possible factors for this include warmer
temperatures, higher levels of humidity
and increased ocular exposure to water.
Gorski M, Genis A, Yushvayev S, et al. Seasonal
variation in the presentation of infectious keratitis. Eye & Contact Lens. 2016 Sep;(42(5):295-7.
■ Researchers recently developed and
evaluated a new meibomian gland dysfunction (MGD)-specific questionnaire
based on accepted tests such as the
Schein symptom survey, tear break-up
time, corneal and conjunctival staining,
abnormal meibum or meibomian gland
atrophy and a normal Schirmer test. The
MGD questionnaire initially contained
24 items targeting the intensity and frequency of 12 symptoms. Using data from
the 69 MGD subjects who completed
the survey and clinical testing, researchers worked through three iterations of
analysis of subject responses to the tests.
The final questionnaire included seven
question pairs. Researchers conclude that
the study is a valid and quantitative measure of symptoms common for patients
with MGD. They acknowledge that further
research is needed to determine whether
the diagnostic efficacy is an adequate
means of differentiating MGD dry eye
subtypes in an independent sample of
normal subjects.
Paugh JR, Kwan J, Christensen M, et al. Development of a meibomian gland dysfuntion—specific
symptom questionnaire. Eye & Contact Lens.
4
Corneal Thickness May Help
Predict CXL Outcomes
R
esearchers recently examined how preoperative
characteristics impact
the outcomes of corneal
collagen crosslinking (CXL) in pediatric patients and found that the
thinnest baseline corneal thickness
impacts the success rate of CXL
after two-year follow up.1
“Keratoconus has potentially
devastating effects on our patients’
quality of life,” says Barry Eiden,
OD, co-founder and president
of the International Keratoconus
Academy. “Younger individuals
(<18) who develop keratoconus
have been shown to progress
faster and develop more advanced
disease with a higher rate requiring
corneal transplantation.”
Research shows that collagen
crosslinking can slow down or halt
the progression of the degenerative
disorder and, when successful,
CXL may stabilize keratoconus
while leading to a permanent flattening of the cornea—a result that
potentially saves individuals from
progressive vision loss or risky
corneal transplants in the future.
This study help to further identify
the particular characteristics of
patients who will more likely be
successful candidates for this leading-edge procedure.
The study included 72 eyes of
52 patients with keratoconus. The
subjects were all under the age
of 18 with a two-year follow up
after CXL. Researchers analyzed
subgroups determined by age, sex,
baseline uncorrected and corrected
distance visual acuities (UCVA,
CDVA), topographic cone location
(central and paracentral), maximum keratometry (k-max) and
REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
corneal thickness at the thinnest
point (thCT).
Results of the study show that
two years after CXL, the mean
UCVA improved considerably,
while the mean thCT decreased
significantly in all patients. The
k-max in patients with paracentral cones and/or a thCT of less
than 450µm was more likely to
progress. The other characteristics
did not present any notable effect
on the progression of CXL after
treatment.
“The challenge,” says Dr. Eiden,
“is for us to develop metrics that
reliably indicate keratoconus
stability vs. progression. In this
study, progression was defined
as a steepening of the maximum
anterior corneal curvature value
(>1D) within 3mm of the apex of
the cone (k-max). Other studies
suggest alternative measures that
may be more reliable indicators.”2
While the efficacy and safety
of CXL in pediatric and adult
patients have been thoroughly
demonstrated, this study sheds
light on factors that help predict
successful outcomes for pediatric
patients undergoing crosslinking.
“Further research surely is needed,” suggests Dr. Eiden. “However,
the take-home message continues
to be the importance of early diagnosis of keratoconus and implementation of treatment methods to
hopefully halt the progression of
the disease prior to its significant
impact on visual function.”
1. Sarac O, Caglayan M, Cakmak HB, Cagil N. Factors
influencing progression of keratoconus 2 years after
corneal collagen cross-linking in pediatric patients.
Cornea. 2016. EPub ahead of print.
2. Duncan JK, Belin MW, Borgstrom M. Assessing
progression of keratoconus: novel tomographic determinants. Eye and Vision. 2016 Mar;3(6).
RCCL
REVIEW OF CORNEA
& CONTACT LENSES
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EDITORIAL REVIEW BOARD
Mark B. Abelson, MD
James V. Aquavella, MD
Edward S. Bennett, OD
Aaron Bronner, OD
Brian Chou, OD
Kenneth Daniels, OD
S. Barry Eiden, OD
Desmond Fonn, Dip Optom M Optom
Gary Gerber, OD
Robert M. Grohe, OD
Susan Gromacki, OD
Patricia Keech, OD
Bruce Koffler, MD
Pete Kollbaum, OD, PhD
Jeffrey Charles Krohn, OD
Kenneth A. Lebow, OD
Jerry Legerton, OD
Kelly Nichols, OD
Robert Ryan, OD
Jack Schaeffer, OD
Charles B. Slonim, MD
Kirk Smick, OD
Mary Jo Stiegemeier, OD
Loretta B. Szczotka, OD
Michael A. Ward, FCLSA
Barry M. Weiner, OD
Barry Weissman, OD
N
early 90% of eye care
providers (ECPs) believe
there is no representative
type of dry eye disease
(DED) patient, according to the
National Eye C.A.R.E. (Current
Attitudes Related to Eye Health)
Survey. The online survey included
more than 1,000 optometrists and
ophthalmologists, as well as more
than 1,200 adults who had been
diagnosed with DED or experienced
dry eye symptoms and used artificial
tears within the past month. Results
provide new statistics on many
aspects of dry eye care, including:
Patient demographics
• 76% said they see more patients aged 18 to 34 with DED
symptoms than 10 years ago.
• 89% of ECPs believe DED is
on the rise due to multi-screen
digital device use.
Screening
• 94% said DED screening
should be part of the comprehensive eye exam.
• 75% believe it’s necessary to
screen for dry eye symptoms in
all patients regardless of age,
gender or lifestyle.
• 88% deem it important to
screen women over 50.
Symptoms
• 79% of patients said their DED
symptoms are currently under
control.
• 52% said their symptoms are
getting worse over time.
• 75% said dry eye impacts their
digital device use and 64% said
it impedes daily activities.
• 54% said DED symptoms impact their ability to work.
• 69% believe dry eye is something they have to live with.
Photo: Paul M. Karpecki, OD
EDITOR-IN-CHIEF
Jack Persico [email protected]
MANAGING EDITOR
Rebecca Hepp [email protected]
ASSOCIATE EDITOR
Adrienne Taron [email protected]
CLINICAL EDITOR
Joseph P. Shovlin, OD, [email protected]
ASSOCIATE CLINICAL EDITOR
Christine W. Sindt, OD, [email protected]
EXECUTIVE EDITOR
Arthur B. Epstein, OD, [email protected]
CONSULTING EDITOR
Milton M. Hom, OD, [email protected]
GRAPHIC DESIGNER
Ashley Schmouder [email protected]
AD PRODUCTION MANAGER
Scott Tobin [email protected]
New Stats Highlight the Need
for More DED Education
Dry eye is on the rise, according to
a new study, and prolonged digital
device use might be to blame.
The survey also revealed the
need for more patient education,
noting that 72% of ECPs said most
patients aren’t familiar with DED.
Patient responses are in accord with
this finding, as 25% said they didn’t
realize eye dryness is a symptom of
a disease, and 32% said they didn’t
know DED could cause long-term
damage to their eyes.
Despite the well-known need for
dry eye care, 72% of patients who
participated in the survey said they
initiated the DED conversation
themselves. More telling, 45% of
patients said they did not feel it was
worth mentioning dry eye because
the ECP did not ask about it.
A
rmed with these new statistics,
ECPs are better equipped to
address dry eye in every exam and
help more patients find the relief
they never knew they needed.
RCCL
Shire Pharmaceuticals. The National Eye C.A.R.E.
(Current Attitudes Related to Eye Health) Survey.
September 2016. Available at www.myeyelove-ecp.
com/dry-eye-info-from-peers. Accessed October
19, 2016.
Advertiser Index
Bausch + Lomb ....Page 7, Cover 3
CooperVision .....................Cover 2
Menicon ............................. Cover 4
REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
5
My Perspective
By Joseph P. Shovlin, OD
A Look at the Androgen Connection
Could hormonal therapy work for dry eye?
T
he elaborate tear
film ecosystem has
to maintain its own
delicate balance, despite influences from
many outside sources and intrinsic
characteristics. Dry eye is one such
condition to disrupt the balance,
giving rise to its newer moniker,
dysfunctional tear film. It likely
results from a host of factors,
including hormone imbalance.
BENEFITS AND RISKS
Androgen has been shown to regulate meibomian gland function, and
any dysregulation has a profoundly
adverse effect. Along with microbial invasion and duct stenosis,
androgen dysregulation promotes
inflammation in meibomian gland
dysfunction (MGD), ultimately
affecting the tear film.1 Androgens
also play a similar role in lacrimal
gland function.2
A deficiency in androgen resulting from attenuation in androgen
synthesis has been documented in
Sjögren’s syndrome, menopause,
aging, men taking androgen
blockers and in complete androgen
insensitivity syndrome.2
Multiple genes coding for androgen activity are present in ocular
tissues, and research suggests androgen levels are depleted in individuals
with significant MGD.1,3
Testosterone is the most
common form of androgen.
Dehydroepiandrosterone (DHEA),
dehydroepiandrosterone sulphate
(DHEAS) and androstenedione
are also referred to as androgens,
though they are actually converted
to testosterone and could therefore
be called pre-androgens.4,5
6
Sex hormone deficiency also plays
a key role in most dry eye disease,
and studies have analyzed various
methods for delivering androgen to
the ocular surface.4 Unfortunately,
investigators found topical testosterone has poor solubility and results
in considerable discomfort and
irritation. A transdermal orphan
preparation was licensed to arGentis Pharmaceuticals, which yielded
good results, as did a progesterone
transdermal delivery option.3 No
testosterone or progesterone preparations have yet made it to market.
In addition to establishing efficacy, a major impediment for approval
is safety. Commercial testosterone’s
use is limited by cost, inconvenience,
discomfort and occasional side effects—especially in women.3 Various
reports show potential side effects
for men with prostate disease and
women with breast cancer (or those
at high risk for each disease) when
using hormone therapy. Although
some theorize hormone supplementation enhances cancer growth,
others reject this notion and show
no association with increased risk.3
Regardless, a careful patient history
is vital before initiating hormone
therapy and, in men, a PSA blood
draw and urologic exam is prudent.
Many of the side effects and
safety concerns stem from oral
formulations or are secondary to increased aromatase activity, elevated
estradiol and its effect at the estrogen receptor. Aromatase activity
increases with age, obesity, alcohol
intake, insulin resistance, breast
cancer, medications, processed diet
and sedentary lifestyle.4 Although
often overlooked in clinical studies,
monitoring aromatase activity and
REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
symptoms of elevated estradiol is
critical to the safe use of testosterone in both sexes.
One alternative is a transdermal
preparation of testosterone (3% to
10%) used once or twice daily. In
addition, practitioners have used
topical DHEA (.03% to 0.5%), the
metabolic precursor to testosterone,
from a compounding pharmacy with some reported success.3
However, results have been inconsistent, with reports of irritation.
PLAY IT SAFE
The significance of androgen for dry
eye therapy is well established, and
some of us will occasionally use it
in a transdermal form, mostly with
female patients. However, we await
additional evidence to ensure meaningful benefit with no harm when
prescribing it to more patients.
Further, we need a safe and effective
commercial product to provide a
remedy for dry eye. Although this
has been part of the discourse for
nearly two decades, a dearth of
studies and clinical trials remains.
Some practitioners will continue
to use the off-label transdermal
testosterone as echelon therapy, but
it’s vital that this be accompanied by
close monitoring for any evidence of
hormonally responsive tumors.
RCCL
1. Sullivan DA, Sullivan BD, Evans JE, et al. Meibomian gland dysfunction and evaporative dry eye.
Ann NY Acad Sci. 2002 June;966:211-2.
2. Sullivan DA, Yamagami H, Liu M, et al Sex steroids,
the meibomian gland and evaporative dry eye. Adv
Exp Med Bio. 2002;506:389-99.
3. Dawson TL. Testosterone eye drops: A novel
treatment for dry eye disease. Ophthalmol Times.
2015 Nov.
4. Glaser R, Dimitrakakis C. Testosterone therapy
in women: Myths and misconceptions. Maturitas.
2013;74(3):230-4.
5. Olson MC, Korb DR, Greiner JV. Evaluation of
warm compress therapy for meibomian gland
dysfunction. Invest Ophthalmol Vis Sci. 2003
May;44:2452.
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RCCL1116_BL Specialty.indd 1
10/12/16 2:49 PM
The GP Experts
By Robert Ensley, OD, and Heidi Miller, OD
The Toric Toolbox: Don’t Forget GPs
To bolster confidence, let’s review the basics of toric GP fitting.
P
atients often report having been told they can’t
wear contact lenses
because of their astigmatism. With advancements in contact lens technology,
however, this is no longer the case.
Major soft lens manufacturers and
custom soft lens laboratories now
offer extended parameter ranges,
allowing even the most highly
astigmatic patients to fall within a
correctable range.
Despite advances in soft lens
technology, however, the gold
standard for quality of vision is
still a gas permeable (GP) lens.
Research shows GP lenses provide
superior vision over their soft
toric lens counterparts—including
for patients with moderate to high
astigmatism of 2.50D or greater.1
Although fitting GP lenses for
astigmatism may seem intimidating, it’s essential knowledge for
contact lens practitioners.
WHEN TO USE A TORIC GP
The normal astigmatic cornea
has two principal meridians 90 degrees apart, each with a different
curvature and resultant refractive
power. In combination with the
tear layer underneath, a GP lens
provides a spherical refracting
surface to correct the astigmatism.
To provide optimal comfort and
vision, a GP lens should center
well over the visual axis and align
closely to the corneal shape.
Typically, you can successfully
fit a spherical GP lens on a cornea
with 2.0D or less of toricity.
Before placing a spherical GP lens
on the eye, you should calculate
8
residual internal
astigmatism, which
originates from the
posterior cornea
and/or crystalline
lens. The calculated
residual astigmatism (CRA) is the
difference between
the total refractive
astigmatism at
the corneal plane
and the anterior
corneal astigmatism
measured by keratometry. You can
find actual residual This 3.0D with the rule cornea is a great candidate for
astigmatism (ARA) a GP lens with back surface toricity.
by subjective
spherocylindrical overrefraction.
with apical bearing along the flat
The ARA is typically less than
meridian, as well as pooling and
the CRA, and simple math will
edge lift along the steep meridisave chair time and frustration, as
an. This misalignment can cause
0.75D or more of ARA can result
several complications, including
in decreased vision.2
lens rocking or flexure; decentraIn this situation, if a GP lens is
tion; corneal molding and distorstill indicated or preferred by the
tion; and corneal desiccation from
patient over a soft toric lens, you
excessive edge lift.
can fit a front surface toric (FST)
Although there is debate among
GP lens. FST GP lenses apply the
practitioners, 2.50D or more of
astigmatic power on the front
corneal astigmatism is a commonsurface, using prism ballasting and ly accepted threshold for using
truncation to stabilize rotation.
back surface toricity.3 By using
two base curves (BC), one for each
Similar to soft toric lenses, FST
principal meridian, back surface
GPs may require rotational comtoricity provides a better lens-topensation using the left add, right
cornea fit. While several methsubtract (LARS) principle.
ods to determine BCs exist, the
As the corneal astigmatism
Mandell-Moore guide is a popular
increases, you should pay greater
and efficient method. Using this
attention to the alignment of the
fit factor, the BC is 0.25D flatter
GP lens to the corneal curvature.
than the flat meridian and 0.50D
Placing a GP lens with a spherical
back surface on a highly astigmat- to 0.75D flatter than the steep meridian, depending on the amount
ic cornea will create a dumbbell
shaped sodium fluorescein pattern of corneal astigmatism. The lens
REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
power on each meridian is then
determined, using the SAM-FAP
principle to account for the tear
lens power.
BITORIC LENSES
Because of differences in the
refractive index of the contact lens
and the tear lens, a GP lens with
back surface toricity will induce
astigmatism of approximately half
the magnitude of the back surface
toricity. In most cases, to correct
this induced astigmatism, you can
add additional astigmatic power
to the front surface of the lens,
making the lens bitoric.
Bitoric lenses are classified into
two designs: spherical power
effect (SPE) and cylindrical power
effect (CPE). When adding astigmatic power to the front surface
of the lens, you must take rotation
of the lens into consideration. SPE
lenses correct astigmatism similar
to a spherical lens, despite having bitoric curves. Thus, the lens
power is equivalent to a spherical
lens and can rotate freely on the
eye without impacting vision.
CPE lenses must be rotationally
stable to avoid inducing further
astigmatism.
To determine the bitoric design,
you should compare both the dioptric BC difference and the back
vertex power difference between
the two principle meridians. If the
dioptric differences between meridians are equal for both BC and
back vertex power, the bitoric is
an SPE design. When the dioptric
differences are unequal, the lens is
a CPE design—typically occurring
when refractive astigmatism is
unequal to corneal astigmatism.
If the back vertex power is 1.5
times the back surface toricity,
the induced astigmatism effectively cancels out the residual
astigmatism. In these cases, the
front surface of the GP can be
made spherical, resulting in a back
surface toric only lens. While this
concept may be confusing, most
laboratories will determine the
necessity for you.
TORIC GP FITTING
MADE EASY
Before the days of empirical
ordering, diagnostic fitting was
performed with standard SPE
fitting sets and overrefraction calculations. Now, you can design a
toric GP lens with a high degree of
accuracy using only keratometry
readings and manifest refraction.1
You can provide this data directly
to your GP lab of choice; however,
if you prefer to calculate the math
yourself, the GP Lens Institute
(www.gpli.info) has several guides
available, including a MandellMoore worksheet. Additionally,
there is a GP toric calculator,
which provides suggested lens
parameters and indicates whether
the lens is an SPE or CPE design.
These resources can help improve
your toric fitting confidence.
RCCL
1. Michaud L, Barriault C, Dionne A, Karwatsky P.
Empirical fitting of soft or rigid gas-permeable
contact lenses for the correction of moderate
to severe refractive astigmatism: A comparative
study. Optometry. 2009 Jul;80:375-83.
2. Sarver MD. A study of residual astigmatism. Am
J Optom. 1969;46(8):578-82.
3. Bennett ES, Layfield KA, Lam D, Henry VA.
Correction of astigmatism. In: Bennett ES, Henry
VA, eds. Clinical Manual of Contact Lenses. 4th
Ed. Philadelphia: Lippincott, Williams & Wilkins;
2014:344-94.
The GPLI Toric Calculator
The GPLI Toric Calculator, available
at www.gpli.info/lens-calculator,
can help you select the correct
lens parameters and either an SPE
or CPE design.
Example 1: SPE
Spectacle Rx: -1.00-3.25x180
Ks: 42.00/45.00
BC: 42.00/44.25
BVP: -1.00/-3.25
ΔBC (2.25 D) = ΔBVP (2.25 D)
Example 2: CPE
Spectacle Rx: +1.00-4.50x180
Ks: 42.00/45.50
BC: 42.00/44.75
BVP: +1.00/-2.50
ΔBC (2.75 D) ≠ ΔBVP (3.50 D)
Example 3: BST
Spectacle Rx: plano-4.50x180
Ks: 41.00/44.00
BC: 41.00/43.25
BVP: 0.00/-3.50
ΔBC (2.25 D) x 1.5 ≈ Δ BVP (3.50 D)
REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
9
Taking Torics to the
T P
Fitting toric lenses has become increasingly straightforward and now presents a viable
option for myriad contact lens wearers.
U
ntil recently, toric
lenses made up a
fraction of contact
lens prescriptions.
Over the last couple
of years, however, toric lens use
has grown substantially—now
making up 13% of our total lens
fits.1 For most eye care practitioners, toric contact lens patients
often seem more demanding than
spherical patients due to the extra time and effort that goes into
fitting them. Fortunately, new
lens types and modalities are simplifying the process and making
these patients happier than ever,
without much added chair time.
Twenty years ago, nearly every
toric lens had to be custom
ordered, and patients had to
wait in our reception area for 20
minutes while the lens settled.
Today, toric fitting sets allow for
instant dispensing, and the lenses
settle within minutes. With much
advancement in this area, we
have far fewer hurdles and can
offer a higher standard of care to
our patients. We live in a culture
marked by instant gratification,
which often presents difficulties
when dealing with issues that
can’t be immediately remedied.
Fortunately, performing contact
lens fittings from trial sets allows
us to deliver care in mere minutes
for the majority of our patients.
In our practice, we still have
patients with low degrees of
astigmatism explain that past
practitioners would not fit them
with lenses because of their
astigmatism. This is no longer the
case, and it is our responsibility
to show our patients the increasingly wide range of options they
have—whether they’re astigmatic
or not. Our toolboxes and lens
options are ever increasing and—
luckily for the less patient among
us—the majority of these lenses
take only minutes to fit.
TORICITY PATTERNS
We are all familiar with astigmatism, but even within each
subtype certain measures require
a better understanding, as they
impact how a patient sees out of
their lenses. For example, it is important to distinguish the differences between limbus-to-limbus
and central corneal astigmatism.
Topography is essential to understanding these distinctions, as research shows significant changes
occur in the shape of the cornea
in the periphery, thus making
conical sections (like with manual
keratometry or autorefractor Ks)
inadequate to predict the extent
of corneal astigmatism.2 If a patient has a small pupil and central
astigmatism during the refraction
but a large pupil in her normal
environment, her true amount of
revealed astigmatism may vary.
This aspect of astigmatism
management is also important for
correctly fitting patients with gas
permeable (GP) lenses. Patients
with central corneal astigmatism,
even with high power (>2.00D),
10 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
may do very well with a spherical lens because the lens fits in
the peripheral cornea in a more
spherical nature. When patients
have limbus-to-limbus astigmatism, on the other hand, they may
reveal only -2.00D in the refraction but need a toric GP lens
at the landing point of the lens
(Figures 1a and b).
Other notable corneal shape
features worth considering are
those that are neither regular
nor irregular in pattern. These
patients may present with variable refractive axis with a minimally variable end point during
the refraction. On topography,
astigmatism in such patients may
appear more like a distorted bow
tie rather than a classic bow tie
with-the-rule (WTR) or againstthe-rule (ATR). These toric patients may benefit from a custom
lens that can mask or vault the
corneal shape.
Astigmatism in patients with
a history of injury, surgery or
ABOUT THE AUTHORS
Dr. Young is an associate at
Specialty Eyecare Group in
Seattle, WA. She specializes
in dry eye and contact
lenses. She graduated
with honors from Pacific
University and received the
AOF award of Excellence in
Contact Lens Patient Care.
Dr. Kading owns Specialty
Eyecare Group, a Seattlebased practice with multiple
locations. He specializes in
anterior segment disease
and custom contact lens
fitting.
By David Kading, OD, and Charissa Young, OD
disease can vary widely—ranging
from normal to irregular. Rather
than suggesting they all need a
custom lens, we refer back to
the refraction and corneal shape
(see “Case Report: Custom vs.
Convenience,” p. 12).
Although some patients may
present with alarming findings on
topography, they may have a relatively clean refraction and minimal aberrations. These patients
may be suited for a standard soft
lens (sphere or toric) rather than
a custom lens, which might offer
only a slight improvement over
the standard lens. Of course, if a
patient has a corneal alteration
that would deem standard soft
lenses impossible, custom lenses
(GP sphere, GP toric, scleral or
custom soft) must be employed.
FITTING PROTOCOL
Every lens manufacturer has its
own contact lens fitting guides,
which tend to be accurate and
worthwhile. Still, every practice
should have a fitting protocol in
place to maximize their success
with any toric lens design:2
1. For patients under 40, we always round up the sphere. Most
trial toric lenses on the market
only come in -0.50D. For example, we round the spherical power up to -1.50D in a patient with
a prescription of -1.25-1.00x175.
2. When working with a patient with cylinder power that is
between the options, we round
down. Because soft contact
lenses rotate about six degrees
on average, rounding down
minimizes visual distortions.3
As an example, we round the
cylinder power down to -0.75D
for a patient with a prescription
of -1.25-1.00x175. Generally,
if the sphere power is between
stock powers and the cylinder
power is between lens options,
our practice is to round up with
the sphere and down with the
cylinder so that the spherical
equivalent equals itself out.
3. For an axis that does not
nail itself directly or clearly
towards one, we round towards
180 for WTR and 90 for ATR.
For a patient with a prescription
of -1.25-1.00x175, we round the
axis to 180 (Figure 2).
For patients with presbyopia,
we may elect to round down for
the spherical component, but
maintain the other two protocols.
Figs 1a. and 1b. Topography is essential for understanding distinctions in corneal shape that affect GP lens fitting.
Patients with apical astigmatism (left) often do well with spherical lenses, while those with limbal astigmatism (right)
often need a toric GP lens.
REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
11
TAKING TORICS TO THE TOP
1. Morgan, P et al. International contact lens prescribing in 2015. Contact Lens Spectrum, January
2016.
2. Read S, Collins MJ, Carney LG, Franklin RJ. The
topography of the central and peripheral cornea.
Invest Ophthalmol Vis Sci. 2006 April;47:1404-15.
3. Momeni-Moghaddam H, Naroo SA, Askarizadeh
F, Tahmasebi F. Comparison of fitting stability of
the different soft toric contact lenses. Cont Lens
Anterior Eye. 2014 Oct;37(5):346-50.
CASE REPORT: CUSTOM
VS. CONVENIENCE
Fig 2. Off WTR astigmatism: If this axis was 15, round closer to the 180,
which would be axis 10. This gives us a final lens power for our patient of
-1.50-0.75x180.
MAINTENANCE AND
PRESCRIPTION GUIDELINES
Lens comfort is paramount for
success in fitting toric lenses.
Addressing and treating dry
eye will decrease chances of eye
rubbing, which can induce lens
rotation and decrease vision
quality. Unless the patient has a
parameter that is not available in
a daily disposable modality, we
recommend dailies to provide the
most comfortable contact lens
wearing experience.
Toric single-use lenses are
available from every major
contact lens manufacturer. There
now exist single-use silicone
hydrogel lenses as well, which
maintain the high oxygen permeability found in two-week or
monthly lenses.
Although fitting most patients
with toric powers is simpler and
more direct than ever before,
practitioners should always
apply a greater degree of scrutiny
for patients who have kerato-
conus or surgically altered eyes.
These irregularities can account
for significantly different needs
and outcomes, typically requiring
customized lenses to maintain
corneal health and maximize
visual outcomes. Most commonly, however, we find toric lenses
provide much of what an average patient seeks. As a result of
advancements in toric lenses over
the last few years, we recommend and fit for toric single-use
lenses far more often than ever
before.
Growth in our practice may be
partially attributable to patients
who elect to be part time wearers—individuals who may have
never considered wearing lenses
in the past. We find that with
the now possible simplified approach, our patients are pleased
that we have taken the time for
their torics, maximizing their
comfort and vision—while also
preventing contact lens dropouts
in our practice.
12 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
RCCL
A 27-year-old presented
to the office wearing a
standard toric soft lens in
one eye and a custom-made
keratoconus lens on the
other. With his toric soft
lens he was 20/25 OD and
with his custom lens 20/30
OS. With overrefraction he
was able to achieve 20/20
with his standard soft
lens but 20/20-3 with the
custom lens. The latter was
a quarterly replacement
lens and he reported
ideal comfort, but felt it
a nuisance to remember
two replacement systems.
The patient is active in
snowboarding and surfing.
Standard refraction revealed
-1.75 cylinder in his left eye
with best corrected vision of
20/25-2.
Because his topography
was not regular, we
understood why his prior
provider had placed him in
a custom lens. We elected
to trial fit him into standard
single-use lenses with toric
parameters to see how much
improvement we could
achieve with a slightly stiffer
modulus daily lens. We were
able to achieve 20/25+2
vision. After discussion with
the patient about the slight
improvement and possible
decreased aberrations he
might have with the custom
lens vs. the daily disposable
lens, the patient elected to
go with the daily disposable
due to convenience and
simplicity.
Up to
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When to Opt for
Scleral Lenses
Irregular cornea
patients in particular
can enjoy the
many benefits that
accompany fitting
scleral lenses.
By Michael J. Lipson, OD
S
oft contact lenses come
with myriad benefits
and have served our
patients well for over
four decades. With a
wide range of new designs and
materials, expanded prescription
ranges and customization options,
we can achieve great comfort and
vision in many more patients than
in the past. Toric soft lenses have
improved greatly in recent years,
expanding the pool of soft contact
lens wearers. But where do you
turn for astigmatic patients who
have not been successful with any
soft lens options you have tried?
Scleral lenses may provide the
solution for practitioners who feel
they’ve run the gamut with soft
lens options.
CANDIDATES FOR
SCLERAL LENSES
Ideal candidates include any patient
with an irregular corneal surface.
This includes patients with keratoconus, pellucid marginal degeneration, post-penetrating keratoplasty (post-PKP), corneal scarring,
irregularities following refractive
surgery and ocular surface disorders. My experience has shown
that patients with these conditions
are most appreciative of the benefits that accompany scleral lenses.
For some patients, fitting sclerals
may eliminate or delay the need for
corneal transplant surgery.1,2
In addition, patients with ocular
surface disease report less dryness
when wearing scleral lenses.3,4 In
cases of ocular surface disease or
persistent epithelial defects, scleral
lens wear can facilitate healing and
long-term corneal health, as they
help maintain a smooth, wet and
protected corneal surface.
Finally, sclerals are a great option
for patients with otherwise healthy
corneas who have very high
prescriptions (high myopia, high
hyperopia and high astigmatism).
The gas permeable (GP) optics of
scleral lenses provide excellent vision because they center well, have
minimal movement and are not
dependent on rotational orientation
to correct astigmatism.
BENEFITS FOR ASTIGMATS
More often than not, my patients
with irregular corneas love scleral
lenses. Irregular cornea patients
who have switched from corneal
GP lenses to sclerals report improved comfort, longer wearing
time and better visual acuity.5 Here
are five benefits scleral lenses can
provide to your irregular cornea
patients:
Visual acuity. Scleral lenses
provide excellent visual acuity
due to the inherent stability and
customization possible with GP
lens optics.6 Rigid materials create
a new front surface for the eye by
positioning the tear lens between
the scleral lens and the cornea,
which corrects astigmatism and
irregularities of the corneal surface. One study found keratoconus
14 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
patients who were fit with scleral
lenses had better acuity than when
previously measured with corneal
GP lenses.7 In patients who have
residual astigmatism, scleral lenses
can be customized with front toric
optics. This astigmatic correction
is placed on the front surface of
the lens and requires a rotationally
stable lens attained via double thin
zones or toric peripheral curves.
Scleral lenses can also incorporate
multifocal designs to provide both
distance and near vision for presbyopes. The lenses center well and
can be made rotationally stable as
described above.
Comfort. With proper fitting,
scleral lenses prove to be extremely
comfortable. Most people describe
the feeling of a properly fit scleral
lens as being more comfortable
ABOUT THE AUTHOR
Dr. Lipson is an assistant
professor at University of
Michigan’s Kellogg Eye Center, Department of Ophthalmology and Visual Science,
at the Northville location. His
clinical practice involves contact lenses with an emphasis
on specialty lenses for overnight
corneal reshaping, keratoconus, post-corneal
transplant, post-refractive surgery and severe
dry eye. He conducts clinical research as
the principal investigator for studies on
corneal reshaping, vision-related quality of
life, myopia control and new lens designs.
He lectures nationally and internationally on
specialty contact lens and research topics. He
is a consultant for Bausch + Lomb’s Specialty
Vision Product (SVP) division, specializing in
education and training on specialty contact
lenses with emphasis on orthokeratology.
Dr. Lipson is the vice president of the Scleral
Lens Education Society and a fellow of the
American Academy of Optometry.
This well-centered scleral lens shows
no edge impingement or scleral
compression. Note the continuity of
blood vessels under the lens.
Photo: Christine Sindt, OD
than soft lenses.8 Not only are they
often more comfortable, in patients
with irregular corneal curvature,
scleral lenses also allow patients to
wear lenses for longer periods each
day compared with soft lenses.9
As practitioners are well aware,
lens comfort is a major factor
contributing to improvement in our
patients’ vision-related quality of
life (QOL).8 Studies show higher
QOL scores for patients wearing
sclerals compared with their previous mode of correction.8,10 In one
study of patients who had ocular
surface disease, 45 of 49 (92%) reported improved quality of life due
to the reduction of photophobia
and discomfort.11 During the fitting
process, if patients have adverse
effects such as lens awareness or
discomfort, various changes in lens
parameters such as diameter, edge
lift, limbal clearance, toric peripheral curves and overall sagittal
depth can be modified to make
scleral lenses more comfortable.
These design changes improve lens
comfort by minimizing edge standoff and ensuring the lens has no
corneal or limbal bearing. Because
of this adaptability, scleral lenses
present a good alternative for a
wide range of patients.
Performance. Due to their size,
scleral lenses do not dislodge with
quick eye movements. In addition,
airborne particles and dust rarely
get under the lens. My clinic sees
significantly fewer patients report-
A decentered corneal GP lens
secondary to corneal irregularity.
Such a patient may experience a
better fit with a scleral lens.
Fitting scleral lenses isn’t a hightech endeavor; all you need is a
diagnostic lens fitting set, slit lamp
and phoropter.
ing foreign objects beneath their
scleral lenses compared with soft
lens options. Further, I’ve yet to see
a case of lenses dislodging. Both of
these factors make sclerals a good
option for patients who play sports
or lead active lifestyles.
Corneal health. Scleral lenses
help maintain a healthy ocular surface.11 Because properly fit sclerals
vault the cornea, they maintain
a layer of tears that continually
bathes the cornea in moisture. In
patients suffering from severe dry
eye or any ocular surface disorder,
scleral lenses provide an ongoing
therapeutic effect by keeping the
corneal surface protected from
trauma, irritation, dehydration and
desiccation.12
Delayed surgical intervention.
The use of scleral lenses may delay
or eliminate the need for corneal
transplant surgery.1 If a patient has
been unsuccessful with previous
modes of contact lens correction,
scleral lenses often provide a
comfortable, less costly and more
convenient solution than surgery,
which comes with numerous follow-up visits, long-term eye drop
use and a long recovery period.
ical observations are necessary to
establish proper fit of a scleral lens:
First is central clearance. During
diagnostic fitting and evaluation, clinicians must evaluate the
thickness of the tear film with an
optic section to ensure full corneal
clearance, record for future use or
give very specific information to a
fitting consultant as needed.
Second is evaluation of limbal
clearance. Long-term bearing on
the limbus will create irritation and
redness.
Third is evaluation of the landing
profile. The goal is to achieve a
uniform, gentle landing 360°.
Excessive bearing will show impingement of conjunctival vessels
and increasing redness over time,
while excessive lift will create
increased lens awareness.
Numerous resources can help
you learn the necessary skills to
gain confidence in fitting scleral
lenses. The Scleral Lens Education
Society (www.sclerallens.org) and
the GP Lens Institute (www.gpli.
info) are both excellent resources.
Additionally, wet labs and fitting
workshops at national and regional
specialty contact lens meetings are
a great opportunity to learn general
scleral skills in a hands-on setting.
It is also worth noting that scleral manufacturers hold dedicated
webinars and workshops to help
clinicians gain experience with a
specific design.
LEARNING TO FIT SCLERALS
Most eye care practitioners already
have the skills required to fit scleral
lenses. But, at the slit lamp, scleral
lens fitters need specific training to
know what to look for. Three crit-
REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
15
WHEN TO OPT FOR SCLERAL LENSES
NOT FOR EVERY PATIENT
While part of the appeal of scleral
lenses is the wide range of patients
for whom they prove successful,
there are some exceptions. A few
patient characteristics may be contraindications for scleral lenses:
• If, for example, you have a
patient with a very small palpebral
fissure with deep-set orbit, sclerals may not be the best option.
These anatomical factors can make
application of the lens difficult for
patients.
• Most patients, even those with
small eyes, can be taught to competently apply and remove scleral
lenses. We do, however, occasionally come across a patient who
just can’t do it and finds repeated
attempts too frustrating to tolerate.
• Patients with low endothe-
lial cell counts (<800 cells/mm2)
represent another contraindication
for scleral lenses. This can occur
with various corneal conditions
but must be carefully evaluated in
post-PKP patients. Patients with
low endothelial cell counts who
wear scleral lenses are more prone
to significant corneal edema and
the potential for graft rejection
reactions.13
Although not a contraindication,
the presence of pre-existing central
corneal scarring will limit the
vision-correcting potential of any
contact lens—including sclerals.
But appearances of scarring can
be deceiving, and clinicians should
still provide a diagnostic fitting
for these patients; scleral lenses
may still provide the best potential
visual acuity.
COMPLICATIONS
As with any contact lens fitting,
complications can occur with scleral lenses.13 Some include corneal
neovascularization, limbal injection, corneal/conjunctival infection, corneal staining and corneal
edema.
To minimize complications, clinicians should provide a thorough
initial fitting evaluation, patient
education on proper disinfection
and handling techniques, and
careful follow-up procedures. In
addition, the use of highly permeable materials and special solutions
during application can minimize
the chance of patients experiencing
these complications. These instances, however, are rare and will occur
less frequently with increased practitioner experience and confidence.
CASE 1
A 56-year-old male was referred to me complaining
of poor vision in the right eye, although his left eye
is fine. He had a history of radial keratotomy in both
eyes in 1992 and LASIK in the right eye in 2003. He
stated he needed better vision for all activities, but
especially for golf. He inquired about additional surgery, glasses or contact lenses.
Other practitioners had tried a variety of CL fitting
modalities over the past six years. The latest correction was a hybrid lens that provided good vision, but
his comfort was not acceptable.
FINDINGS
• Unaided VA: OD 20/70-, OS 20/30+
• Refraction: -1.25 -4.75 x 140 20/50 OD; +0.50 -1.25
x 080 20/25 OS
• Slit lamp: Eight radial RK incisional scars and two
“T-cuts” superior and inferior, as well as trace LASIK
flap interface visible, superiorly-hinged OD; eight RK
incisional scars OS.
• Topography: Irregular astigmatism with inferiornasal steepening OD.
• Corneal diameter: 11.8mm
evaluation went well as
far as comfort and vision
correction. I used an oblate back surface design
to more closely parallel
the post-refractive corneal topography.
Corneal topography of the
right eye.
First lens ordered:
• BC: 9.24 oblate design
• OAD: 16.0
• Power: -7.00
• Sagittal depth:4.40mm
At one-week follow-up he reported comfortable
wearing time of eight hours, but he continued to
wear them for a total of about 10 hours a day. He
reported his visual acuity as quite good, and he
read 20/25 with no distortions. Slit lamp evaluation
showed moderate temporal hyperemia, 200 microns
of central clearance and slight temporal conjunctival
prolapse.
I ordered a new lens with a toric landing zone (90
microns flatter in the horizontal meridian with no
change vertically). With the new lens, one month
SOLUTION
After discussing and dismissing the potential of later, he reported excellent vision (20/25+), comfortsurgical correction and glasses, I educated him on able wearing time of 12 hours a day and only slight
scleral lenses and how different they were than the and occasional redness. He also reported much betprevious contact lenses he had tried. Diagnostic ter vision on the golf course!
16 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
F
itting your patients with
irregular corneas with scleral
lenses can be gratifying and is a
worthwhile skill set to incorporate
into your practice. Scleral lenses
can provide comfortable lens wear,
clear vision and longer wear time.9
As a practitioner, it is rewarding to
hear patients who were unsuccessful in other contact lens modalities
report clear vision and an improved
quality of life with properly fit
scleral lenses. Further, as sclerals
are specialty lenses, they can generate greater revenue per patient for
your practice from higher fitting
fees and enthusiastic word-ofmouth referrals for other specialty
patients.
RCCL
1. Deloss KS, Fatteh NH, And Hood CT. Prosthetic
replacement of the ocular surface ecosystem
(PROSE) scleral device compared to keratoplasty
for the treatment of corneal ectasia. Am J Ophthal. 2014;158:974-82.
2. Severinsky B, Behrman S, Frucht-Pery J, Solomon A. Scleral contact lenses for visual rehabilitation after penetratingkeratoplasty: Long term
outcomes. Cont Lens Ant Eye. 2014;37:196-202.
3. Schornack MM, Baratz KH, Patel SV, Maguire
LJ. Jupiter scleral lenses in the management of
chronic graft versus host disease. Eye Cont Lens.
2008;34(6):302-5.
4. Rosenthal P, Cotter J. The Boston scleral lens
in the management of severe ocular surface disease. Ophthalmol Clin N Am. 2003;16:89-93.
5. Segal O, Barkana Y, Hourovitz D, et al. Scleral
lenses may help where other modalities fail.
Cornea. 2003;22:308-10.
6. Stason WB, Razavi M, Jacobs DS, et al. Clinical
benefits of the boston ocular surface prosthesis.
Am J Ophthalmol 2010;149:54–61.
7. Schornack MM, Patel SV. Scleral lenses in the
management of keratoconus. Eye Contact Lens
2010;36:39-44.
8. Bergmanson JP, Walker MK and Johnson LA.
Assessing scleral contact lens satisfaction in a
keratoconus population. Optom Vis Sci 2016;93.
Epub ahead of print.
9. Ortenberg I, Behrman S, Geraisy W and Barequet I. Wearing time as a measure of success of
scleral lenses for patients with irregular astigmatism. Eye Contact Lens. 2013;39:381-4.
10. Visser E-S, Visser R, van Lier H, Otten H. Modern scleral lenses part II: patient satisfaction. Eye
Contact Lens. 2007;33:21-5.
11. Romero-Rangel T, Stavrou P, Cotter J, et al.
Gas permeable scleral contact lens therapy in ocular surface disease. Am J Ophthal. 2000;130:2532.
12. Van der Worp E, Bornman D, Ferreira DL, et
al. Modern scleral lenses: a review. Cont Lens Ant
Eye. 2014;37:240-50.
13. Walker MK, Bergmanson JP, Miller WL, et al.
Complications and fitting challenges associated
with scleral contact lenses: A Review. Cont Lens
and Ant Eye. 2015;39:88-96.
CASE 2
A 29-year-old male was referred to me with a
history of keratoconus in both eyes. When he
was first diagnosed at 19, he was prescribed
corneal GP lenses. He wore those for about
five years with varying degrees of comfort.
After hearing about new contact lens options
for keratoconus, he pursued other modalities
over the next five years, including: piggyback,
Corneal topography of
hybrid and special soft lenses.
the left eye.
He came in wearing the special soft lenses
that provided good comfort, but he complained that vision was not
acceptable and that he had to replace them every two months due to
deposits.
FINDINGS
• Current corrected VA: 20/30- OD, 20/40 OS.
• Refraction: -4.25 -4.75 x80 20/70 OD, -5.50 -5.25 x 115 20/80 OS.
• Slit lamp: Apical thinning and 1-2+ vertical striae OD; apical thinning,
2+ vertical striae and trace hazy scar OS.
• Topography: Irregular astigmatism with inferior temporal steepening
and inferior temporal apex OU.
• Corneal diameter: 12.0mm
SOLUTION
After discussing his history and various contact lens options, I recommended we proceed with scleral lenses.
Diagnostic evaluation for fitting his left eye went well. He was happy
with both the vision and comfort with the scleral lenses. I used a prolate
back surface design in a 17.0mm lens.
Initial diagnostic lens for the left eye:
• Sagittal depth: - 4900 microns
• Base curve: -7.8
• Diameter: 17.0
• Power: -2.00
• Over-refraction: 3.50 sph 20/20-
Initial diagnostic
lens showed
small central
bearing.
The initial diagnostic lens showed slight central bearing but good limbal
clearance and good edge alignment.
The first lens I ordered had 150 microns greater sagittal depth than
the diagnostic lens.
First lens ordered for the left eye:
• Sagittal depth: 5050 microns
• BC; 7.80 prolate design
• OAD: 17.0
• Power: -5.50
At one-week follow-up he reported comfortable wearing time of 14 hours and reported
not needing to use any lubricating drops. He
reported his visual acuity in his left eye as very
good, and he read 20/20- with no distortions.
Slit lamp evaluation showed minimal hyperemia that did not change with increased wearing time.
The patient’s left eye
after wearing the
prescribed scleral lens
for six hours.
REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
17
1 CE
Credit
(COPE Approval
Pending)
SURGICAL OPTIONS for the
Correction of ASTIGMATISM
Today’s sophisticated surgical tools and techniques offer dramatically improved
outcomes over the imprecise early efforts of yesterday.
By Kristen Brown, OD
E
ye care practitioners
are familiar with
corneal astigmatism, as this common
refractive condition
caused by unequal curvature
along the two principal meridians greets us in the exam chair
every day. Classified by axis,
astigmatism is either with-therule (WTR), against-the-rule
(ATR) or oblique; it can be
further categorized as regular or
irregular. These terms and their
clinical manifestations are a part
of routine practice; however, the
advent of wavefront analysis in
recent years has enhanced our
understanding of irregular astigmatism with the classification of
higher-order aberrations such as
coma, trefoil and quadrafoil.1
The portfolio of options for
the surgical correction of astigmatism has expanded significantly over the past two decades.
Photorefractive procedures such
as laser in situ keratomileusis
(LASIK) and photorefractive
keratectomy (PRK) are well
established. The introduction
of femtosecond-laser (FS) technology has opened the door for
new surgical strategies including
laser-assisted cataract surgery
and the recently FDA approved
small-incision lenticule extraction
(SMILE) procedure. Meanwhile,
incisional options such as astigmatic keratotomy (AK) continue
to evolve as FS technology adds
a level of precision not seen with
manual techniques. FS lasers can
be combined with toric intraocular lenses (IOLs) to address the
growing demand for refractive
cataract surgery.
Surgical correction of astigmatism has a promising future.
Improved strategies are evolving
in the areas of topography-guided laser procedures, ray tracing, patterned corneal collagen
crosslinking and toric multifocal
intraocular lenses.2,3
THE RISING TIDE
Astigmatism accounts for about
13% of all refractive error.4 As
much as 90% of the world’s
population has some degree of
astigmatism, including 20%
with 1.5D or more cylinder.5
Approximately 63% of individuals under 40 have 0.25D or more
astigmatism, while most have less
than 1D.6-8
Research reveals that myopia
and astigmatism are increasing at
an alarming rate, both surfacing
at a younger age and growing in
prevalence throughout the early
and adolescent years.9,10 In the
United States, myopia prevalence
is nearly twice what it was 30
years ago.11-13 In 2015, investigators found that 50% of urban
populations in East Asia were
myopic, with 90% of university
students displaying myopia or
18 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
myopic astigmatism.10 Research
estimates that myopia—and
presumably myopic astigmatism—will affect nearly six
billion people by the year 2050.13
This astonishing rise has ramifications for eye care professionals
around the world involved in
the prevention, management and
surgical correction of myopia and
astigmatism.
FROM AK TO SMILE:
A RETROSPECTIVE ON
SURGICAL METHODOLOGY
Astigmatic keratotomy was one
of the first forms of refractive
surgery developed to correct
astigmatism. AK became available in the United States shortly
after radial keratotomy (RK) was
introduced in 1978.14 During AK,
peripheral arcuate incisions are
made with a diamond blade knife
along the steep axis of corneal
astigmatism to flatten that axis.15
Though RK has fallen out of
favor due to diurnal fluctuation
in acuity and unpredictable longterm results, AK is still a conveABOUT THE AUTHOR
Dr. Brown is clinical director of
TLC Laser Eye Centers of Boston, MA, and Providence, RI.
She is a member of the TLC
Clinical Director Advisory
Group and holds a faculty
appointment at the New
England College of Optometry.
She is involved in clinical research,
teaching and lecturing.
Release Date: November 2016
Expiration Date: November 1, 2019
Goal Statement: Surgical correction of
astigmatism has a promising future. This
article discusses the improved strategies
that are evolving in the areas of topographyguided laser procedures, ray tracing,
patterned corneal collagen crosslinking and
toric intraocular lenses.
Faculty/Editorial Board: Kristen Brown, OD
Credit Statement: COPE approval for 1 hour
Preoperative topography of a
patient’s left eye prior to having
undergone a combined one-site
cataract and trabeculectomy surgery
with LRI. Regular 5.5D of with-therule astigmatism can be seen with an
axis of 80°.
Photo: Allister Gibbons, MD
bances (ghosting, glare or halo)
and residual refractive error are
rare and most resolve after the
first year.28 Customized ablation
profiles materialized about a
decade ago when aberrometers
became available to measure the
wavefront of the eye.
Wavefront data is obtained
by projecting a flat plane or
“wave” of light into the eye and
measuring the location of the
corresponding light spots reflected from the retina. The relative
location of reflected light is then
used to calculate the power of the
optical system where each spot
of light enters the eye. The goal
of custom or wavefront-guided
(WFG) laser ablation is to reduce
the imperfections or higher-order aberrations (HOAs) of the
optical system.29 Original “conventional” laser ablation profiles
with the very first excimer lasers
did not aim to correct HOAs
and tended to create an oblate
(centrally flat) corneal profile.
They were also more likely to
induce postoperative HOAs like
spherical aberration. Wavefrontoptimized (WFO) ablations were
also designed to customize laser
ablations but do not rely on
wavefront measurement of the
eye. WFO treatments are based
on refraction data, keratometry
and a peripheral ablation profile specific to each cornea. This
peripheral algorithm results in
a more prolate corneal shape
Photo: Allister Gibbons, MD
nient, relatively inexpensive procedure. Compared with LASIK or
PRK, however, astigmatic keratotomy is less predictable and
has a lower range of astigmatic
effect.16-19
The application of FS lasers has
given surgeons better control of
the length, depth and location of
AK incisions, leading to finer precision, less risk and better visual
outcomes.20-23 A big advantage of
FS AK is that cuts can be penetrating or intrastromal without
a break in the epithelium. This
allows for titration of the effect
and better patient comfort.24
Low to moderate astigmatism
(1D to 3D) can also be corrected
with intracorneal ring segments
(ICRS). The goal of ICRS implantation is typically to delay or
prevent corneal graft surgery; it
is most often employed in ectatic
conditions such as keratoconus,
post-LASIK ectasia and pellucid
marginal degeneration.25 As with
AK, ICRS can be done manually
or with an FS laser to create tunnels that are more precise, more
predictable and associated with
fewer complications and similar
visual outcomes.26
Photoablation with an excimer
laser (i.e., LASIK and PRK) has
become the prevailing surgical
option for patients who desire
an alternative to eyeglasses and
contact lenses. The FDA first
approved the excimer for spherical myopia in 1995, but the
option to treat astigmatism and
hyperopia didn’t become available until several years later. A
2004 study found that one to
two million people in the United
States undergo LASIK or PRK.27
US Military personnel opt for refractive laser surgery at twice the
rate of the general population.28
Adverse events such as dry eye
symptoms, night vision distur-
The same patient three months after
combined one-site cataract and
trabeculectomy surgery with LRI. In
retroillumination, we can verify the
rotational stability of the lens at 80°.
following laser ablation and is
thought to induce fewer postoperative HOAs.30
Custom ablations are indicated
for myopia as high as -12D with
astigmatism up to -3.75D on
of continuing education credit is pending for
this course. Check with your state licensing
board to see if this counts toward your CE
requirements for relicensure.
Joint-Sponsorship Statement: This
continuing education course is jointsponsored by the Pennsylvania College of
Optometry.
Disclosure Statement: The author has
no financial interest in any products
mentioned in this article.
REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
19
SURGICAL OPTIONS FOR THE CORRECTION OF ASTIGMATISM
most wavefront-guided excimer
laser platforms. Similarly, wavefront-optimized ablation profiles
can correct up to -12D myopia
and provide an expanded range
of astigmatism correction—up
to -6D, for example—with the
Wavelight EX500 excimer laser
(Alcon).
Wavefront-guided visual
outcomes have been excellent
compared with conventional ablation profiles; however, they are
dependent of aberrometry measurements which are affected by
pupil size, pupil centration and
accommodation.31 In addition,
corneal, lens and vitreous opacities limit the ability to capture
good wavefront data. As lenticular aberrations change over time,
correcting the wavefront of the
whole eye may not be an optimal
strategy for treating irregular
astigmatism and other HOAs.
TOPOGRAPHY-GUIDED
LASER ABLATION
Refractive surgeons in the United
States can now perform topography-guided laser ablation, which
been growing in popularity outside the United States for many
years.32 The FDA granted approval for topography-guided treatment on normal (i.e., previously
untreated) eyes on the Nidek
laser in October of 2013 and the
Alcon laser system in 2015.
Topography-guided ablation
normalizes or smooths the corneal surface by correcting only the
HOAs that arise from the cornea, leaving internal aberrations
unchanged. Topography-guided
technology integrates placido
disc topography, keratometry
and pupillometry in a single
diagnostic device that integrates
with planning software and
excimer laser technology.32 Unlike
with WFG ablations, informa-
tion about sphere and regular
astigmatism (the lower-order
aberrations) is not captured by
topography and must be obtained
separately, by refraction, for
example.
Recent research evaluating
the safety and effectiveness of
topography-guided LASIK found
that visual symptoms such as
glare, halo and starbursts were
reduced—and, more surprisingly,
30.9% of subjects gained one or
more lines of uncorrected visual
acuity compared with preoperative best corrected visual acuity.32
Outside the United States, topography-guided procedures can be
conducted on highly aberrated
eyes such as those with small or
decentered optical zones from
previous corneal refractive surgery, eyes with naturally occurring irregular corneal astigmatism
or irregular astigmatism from
trauma.33,34
With age, the axis of astigmatism shifts toward an ATR orientation primarily due to changes
in the cornea, not the lens. A
reduction in eyelid tension over
time may partly explain this shift,
as internal astigmatism remains
relatively stable with age.35
Despite minimally invasive
approaches, modern cataract surgery can induce corneal astigmatism even with the small incisions
made in the peripheral cornea.
Like AK, incisions made for cataract surgery entry wounds cause
flattening in the meridian incised
and steepening in the meridian 90
degrees away.36 Superior incisions
cause flattening of the vertical
meridian or an increase in ATR
astigmatism, while temporal
incisions lead to flattening in the
horizontal meridian or an increase in WTR astigmatism. The
amount varies with individual
differences in corneal biomechan-
20 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
ical properties, surgical technique
and type of surgery performed.37
Understanding and managing surgically induced corneal
astigmatism (SICA) is necessary
for surgeons to succeed in an era
of patients opting for refractive
cataract surgery, which includes
post-op uncorrected emmetropia
as a goal. Many have had previous LASIK or PRK and expect to
return to post-laser, spectacle-free
status.
LRIs AND IOLs
During cataract surgery, corneal
astigmatism can be corrected
with limbal relaxing incisions
(LRIs), toric IOLs or a combination of the two. In addition, a
femtosecond laser can be employed to assist the surgeon with
steps that are typically performed
manually. Laser-assisted cataract
surgery (LACS) adds a level of
precision to the procedure, which
may improve visual outcomes
and lessen the risk of postoperative complications such as
endothelial cell loss and macular
edema.38 LRIs are positioned
more peripherally in the cornea
than AK incisions and are preferred in cataract surgery since
the same incision can be used for
phacoemulsification. Compared
with astigmatic keratotomy, LRIs
are associated with less pain and
less induced irregular astigmatism.39 Further, they are quick
and effective at reducing up to
1.5D of corneal astigmatism.
Toric IOLs are a better option
for surgical correction of moderate (1.5D to 4.25D) astigmatism.
Several toric IOLs of various
material and astigmatic power are available in the United
States, including the Staar Toric
(Staar Surgical), Acrysof IQ Toric
(Alcon), Tecnis Toric (AMO) and
Trulign Toric (Bausch + Lomb).
For successful correction of
astigmatism, toric IOLs must be
aligned with the visual axis and
the steep meridian of the cornea.
Some lenses can rotate, which
will reduce the effectiveness and
leave residual astigmatism at a
new, often oblique, meridian.
Anterior and posterior corneal astigmatism must both be
considered when planning IOL
surgery—particularly in patients
who want less dependence on
spectacle correction. Inaccuracies
arise when posterior corneal
astigmatism is measured with
the assumption that there is a
fixed-ratio relationship with the
anterior corneal curvature.40 The
Cassini Corneal Shape Analyzer
(i-Optics) is a new topographer
that uses LED ray tracing technology with 700 diode lights to
measure anterior and posterior
corneal astigmatism. Advances in
cylinder and axis measurement
precision can be useful for preoperative planning of toric IOL
implants, particularly in post-laser refractive surgery patients.41
In addition, the use of intraoperative aberrometry can
guide IOL power selection. The
Optiwave Refractive Analysis
system (Alcon) employs wavefront interferometry to produce a
fringe pattern; distortions in this
pattern are then translated into
refractive values.42 Research on
toric IOL power selection aided
by intraoperative aberrometry
reveals that patients were 2.4
times more likely to have less
than 0.50D of residual refractive
astigmatism when an intraoperative aberrometer was used.43
Advantages of LACS over
manual cataract surgery include
the customization of corneal incisions, precision and the
centration of the capsulotomy for
improved refractive stability and
predictability. Fragmenting the
lens before phacoemulsification
is another advantage of LACS
that is believed to be less likely to
induce endothelial cell loss.43 For
astigmatism greater than 4.25D
at the corneal plane, it may be
necessary to combine LRIs with
toric IOLs or subsequent LASIK
or PRK for up to 10D corneal
astigmatism correction.
The newest frontier combines
Pre-op topography (Vario, Alcon) of a highly astigmatic patient to be treated
with Wavelight FS200/EX500 (Alcon) wavefront optimized system. Left
image: +4.25 -4.75x175 20/25 OD. Right image: +4.50 -5.25x005 20/25 OS.
Pentacam imaging of the same WFO-treated patient (right eye only). Left
image: pre-op OD. Right image: one month post-op OD.
At one month post-op, UCVA is 20/20 plano -0.25x005 20/20 OD.
REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
21
SURGICAL OPTIONS FOR THE CORRECTION OF ASTIGMATISM
astigmatism and presbyopia treatment in one IOL. The recently
FDA approved Tecnis Symfony
Toric IOL (AMO) and the forthcoming Acrysof IQ Restor Toric
(Alcon) are two early entrants
into this emerging category.
NO LONGER AN
AFTERTHOUGHT
Although significant astigmatism is typically defined as 1D
or more, amounts as low as
0.25D can impact visual acuity
or visual quality in some individuals. Planning and predicting the
outcome of refractive surgery is
the foremost challenge a surgeon
faces. With the explosion of more
advanced technology and improved surgical outcomes, there
is increasing expectation that
refractive procedures can and will
provide excellent visual results
with minimal risk, and that
astigmatism correction must now
be part and parcel of the surgical
approach. Future advances will
focus on corneal biomechanical
properties and wound healing
response, which is one of the few
remaining limitations affecting
the predictability and stability of
refractive surgery.
RCCL
1. Kelly JE, Mihashi T, Howland HC. Compensation
of corneal horizontal/vertical astigmatism, lateral
coma and spherical aberration by internal optics
of the eye. J Vision. 2004;4:262–71.
2. Cummings AB, Kelly GE. Optical ray tracing-guided myopic laser in situ keratomileusis:1-year clinical outcomes. Clinical Ophthalmology. 2013;7:1181–91.
3. Ibrahim Seven MS, Sinha Roy A, Dupps WJ
Jr. Patterned corneal collagen crosslinking for
astigmatism: Computational modeling study. J
Cataract Refract Surg. 2014 June;40(6):943–53.
4. Read SA, Collins MJ, Carney LG. A review of
astigmatism and its possible genesis. Clin Exp
Optom. 2007;90(1):5–19.
5. Porter J, Guirao A, Cox IG, Williams DR. Monochromatic aberrations of the human eye in a large
population. J Opt Soc Am A. 2001;18:1793–1803.
6. Ferrer-Blasco T, Montés-Micó R, Peixoto-de-Matos SC, et al. Prevalence of corneal
astigmatism before cataract surgery. J Cataract
Refract Surg. 2009;35:70-5.
7. Saunders H. Age-dependence of human
refractive errors. Ophthalmic Physiol Opt.
1981;(1):159–74.
8. Fledelius HC, Stubgaard M. Changes in refraction and corneal curvature during growth and
adult life. A cross-sectional study. Acta Ophthalmol. 1986;64:487–91.
9. Gwizada J, Grice K, Held R, et al. Astigmatism
and the development of myopia in children.
Vision Research. 2000;40:1019–26.
10. Smith MJ, Walline JJ. Controlling myopia
progression in children and adolescents. Adolesc
Health Med Ther. 2015;6:133-40.
11. Read SA. Ocular and environmental factors
associated with eye growth in childhood. Optom
Vis Sci. 2016;93:1031–41.
12. Rose KA, Morgan IG, Ip J, et al. Outdoor activity reduces the prevalence of myopia in children.
Ophthalmology. 2008;115:1279–85.
13. Holden BA, Fricke TR, Wilson DA. Global prevalence of myopia and high myopia and temporal
trends from 2000 through 2050. Ophthalmology.
2016 May;123(5):1036-42.
14. Waring GO. Refractive keratotmy for myopia
and astigmatism. St Louis, MO: Mosby-Year Book;
1992.
15. Hanna KD, Jouve FE, Waring GO 3rd, Ciarlet
PG. Computer simulation of arcuate keratotomy
for astigmatism. Refract Corneal Surg. 1992 MarApr;8(2):152-63.
16. Waring GO 3rd, Lynn MJ, McDonnell PJ.
Results of the prospective evaluation of radial
keratotomy (PERK) study 10 years after surgery.
Arch Ophthalmol. 1994;112(10):1298-308.
17. Kemp JR, Martinez CE, Klyce SD, et al. Diurnal
fluctuations in corneal topography 10 years after
radial keratotomy in the Prospective Evaluation of
Radial keratotomy Study. J Cataract Refract Surg.
1999 Jul;25(7):904-10.
18. Kohnen T, Buhren J. Corneal first-surface aberration analysis of the biomechanical effects of
astigmatic keratotomy and a micro-keratome cut
after penetrating keratoplasty. J Cataract Refract
Surg. 2005;31:185–9.
19. Montes-Mico R, Munoz G, Albarran-Diego C, et
al. Corneal aberrations after astigmatic keratotomy combined with laser in situ keratomileusis. J
Cataract Refract Surg. 2004;30:1418–21.
20. Abbey A, Ide T, Kymionis GD, Yoo SH. Femtosecond laser-assisted astigmatic keratotomy
in naturally occurring high astigmatism. Br J
Ophthalmol. 2009;93(12):1566–9.
21. Hoffart L, Proust H, Matonti F, et al. Correction
of post-keratoplasty astigmatism by femtosecond
laser compared with mechanized astigmatic keratotomy. Am J Ophthalmol. 2009;147(5):779–87.
22. Oshika T, Shimazaki J, Yoshitomi F, et al.
Arcuate keratotomy to treat corneal astigmatism
after cataract surgery: a prospective evaluation of
predictability and effectiveness. Ophthalmology.
1998;105(11):2012–6.
23. Aristeidou A, Taniguchi EV, Tsatsos M, et al.
The evolution of corneal and refractive surgery
with the femtosecond laser. Eye and Vision. 2015
Jul 14;2:12.
24. Bahar I, Levinger E, Kaiserman I, et al.
IntraLase-enabled astigmatic keratotomy for
post-keratoplasty astigmatism. Am J Ophthalmol.
2008;146(6):897–904.
25. Cosckunseven E, Kymionis GD, Tsiklis NS, et
al. One-year results of intrastromal corneal ring
segment implantation (KeraRing) using femtosecond laser in patients with keratoconus. Am J
Ophthalmol. 2008;145(5):775–9.
26. Piñero DP, Alio JL, El Kady B, et al. Refractive
and aberrometric outcomes of intracorneal ring
segments for keratoconus: mechanical versus
femtosecond-assisted procedures. Ophthalmology. 2009;116(9):1675–87.
27. Duffey RJ, Leaming D. Trends in refractive
22 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
surgery in the United States. J Cataract Refract
Surg. 2004;30(8):1781–5.
28. Blitz JB, Hunt DJ, Cost AA. Post Refractive
surgery complications and eye disease, active
duty US armed forces 2005-2014. MSMR. May
2016;23(5).
29. Subbaram MV, MacRae SM. Customized LASIK
treatment for myopia based on preoperative
manifest refraction and higher order aberrometry:
the Rochester nomogram. J Refract Surg. 2007
May;23(5):435-41.
30. Randleman JB et al. Outcomes of wavefront-optimized surface ablation. Ophthalmology
2007 May;114(5):983-8.
31. Sáles CS, Manche EE. One-year outcomes
from a prospective, randomized, eye-to-eye comparison of wavefront-guided and wavefront-optimized LASIK in myopes. Ophthalmology. 2013
Dec;120(12):2396-402.
32. Stulting RD, Fant BS, The T-CAT Study
Group. Results of topography-guided laser in situ
keratomileusis custom ablation treatment with
a refractive excimer laser. Cataract Refract Surg.
2016 Jan;42(1):11-8.
33. Alio JL, Belda JI, Osman AA, Shalaby AMM.
Topography-guided laser in situ keratomileusis
(TOPOLINK) to correct irregular astigmatism
after previous refractive surgery. J Refract Surg.
2003;19:516–27.
34. Lin DT, Holland S, Tan JC, Moloney G. Clinical results of topography-based customized
ablations in highly aberrated eyes and keratoconus/ectasia with cross-linking. J Refract Surg.
2012;28(11 suppl):S841-8.
35. Anstice J. Astigmatism—Its components and
their changes with age. Am J Optom Arch Am
Acad Optom. 1971;48:1001–6.
36. Simsek S, Yaşar T, Demirok A, et al. Effect of
superior and temporal clear corneal incisions on
astigmatism after sutureless phacoemulsification.
J Cataract Refract Surg. 1998;24:515–8.
37. Dupps WJ Jr, Wilson SE. Biomechanics and
wound healing in the cornea. Exp Eye Res.
2006;83(4):709-20.
38. Callou TP, et al. Advances in femtosecond
laser technology. Clinical Ophthalmology 2016:10
697–703.
39. Settas G, Settas C, Minos E, et al. Photorefractive keratectomy (PRK) versus laser assisted
in situ keratomileusis (LASIK) for hyperopia
correction. Cochrane Database Syst Rev. 2012;(6):
CD007112.
40. Koch DD. The posterior cornea: hiding in plain
sight. Ophthalmology. 2015;122(6):1070–1.
41. Kanellopoulos J, Asimellis G. Distribution and
repeatability of corneal astigmatism measurements (magnitude and axis) evaluated with
color light emitting diode reflection topography.
Cornea. 2015;34(8):937–44.
42. Huelle JO, Katz T, Druchkiv V, et al. First
clinical results on the feasibility, quality and
reproducibility of aberrometry-based intraoperative refraction during cataract surgery. British J
Ophthalmol. 2014;98(11):1484-91.
43. Hatch KM, Woodcock EC, Talamo JH. Intraocular lens power selection and positioning with
and without intraoperative aberrometry. J Refract
Surg. 2015;31(4):237–42.
CE TEST ~ NOVEMBER 2016
1. Which of the following procedures was first used to correct astigmatism?
a. Toric intraocular lenses.
b. LASIK.
c. Astigmatic keratotomy.
d. Small-incision lenticule extraction.
2. Which procedure is associated with fluctuation in vision and unpredictable
results long term?
a. PRK.
b. Laser-assisted cataract surgery.
c. Radial keratotomy.
d. Astigmatic keratotomy.
3. Which statement is true regarding custom excimer laser ablation (LASIK/
PRK)?
a. Custom laser ablation treats higher-order and lower-order aberrations.
b. Custom laser vision correction treats only lower-order aberrations.
c. Custom laser ablation treats only higher-order aberrations.
d. Custom laser ablation treats neither higher-order nor lower-order
aberrations.
4. Wavefront data is obtained by which device?
a. Phoropter.
b. Aberrometer.
c. Keratometer.
d. Pupillometer.
5. Topography-guided laser ablation corrects:
a. Internal aberrations.
b. Lenticular opacities.
c. Hyperopia.
d. Aberrations of the corneal surface.
6. Normalizing the corneal surface with topography-guided laser ablation:
a. Has been associated with improved uncorrected acuity over preoperative
best-corrected acuity in some patients.
b. Has been associated with a high risk of losing best-corrected acuity in many
patients.
c. Is not currently FDA approved in the United States.
d. Corrects only symmetric corneal astigmatism.
7. Toric Intraocular lenses are a good option for patients with:
a. A low amount of internal astigmatism.
b. A moderate to high amount of corneal astigmatism.
c. Macular degeneration.
d. A moderate amount of lenticular toricity.
8. Which statement is true regarding limbal relaxing incisions?
a. Should never be combined with toric intraocular lenses.
b. Should only be performed manually.
c. Can be performed with an excimer laser.
d. Can be performed with a femtosecond laser.
EXAMINATION ANSWER SHEET
Surgical Options for the Correction of Astigmatism
Valid for credit through November 1, 2019
Online: This exam can also be taken online at www.reviewofcontactlenses.com.
Upon passing the exam, you can view your results immediately. You can also
view your test history at any time from the website.
Directions: Select one answer for each question in the exam and completely
darken the appropriate circle. A minimum score of 70% is required to earn credit.
Mail to: Jobson Optometric CE, Canal Street Station, PO Box 488 New York, NY 10013
Payment: Remit $20 with this exam. Make check payable to Jobson Medical
Information LLC.
Credit: COPE approval for 1 hour of CE credit is pending for this course.
Sponsorship: Joint-sponsored by the Pennsylvania College of Optometry
Processing: There is an eight-to-10 week processing time for this exam.
Answers to CE exam:
A
B
C
1.
A
B
C
2.
A
B
C
3.
A
B
C
4.
A
B
C
5.
6.
7.
8.
9.
10.
D
D
D
D
D
A
B
C
D
A
B
C
D
A
B
C
D
A
B
C
D
A
B
C
D
Evaluation questions (1 = Excellent, 2 = Very Good, 3 = Good, 4 = Fair, 5 = Poor)
Rate the effectiveness of how well the activity:
1
2
3
4
5
11. Met the goal statement:
12. Related to your practice needs:
1
2
3
4
5
13. Will help improve patient care:
1
2
3
4
5
1
2
3
4
5
14. Avoided commercial bias/influence:
15. How do you rate the overall quality of the material? 1
2
3
4
5
16. Your knowledge of the subject increased: Greatly
Somewhat
Little
17. The difficulty of the course was:
Complex
Appropriate Basic
18. How long did it take to complete this course? _________________________
19. Comments on this course: _________________________________________
___________________________________________________________________
20. Suggested topics for future CE articles: ______________________________
___________________________________________________________________
Identifying information (please print clearly):
First Name
Last Name
Email
The following is your:
Home Address
Business Address
Business Name
9. Which statement is false regarding femtosecond laser technology?
a. The use of FS lasers in ocular surgery has expanded significantly over the
past 20 years.
b. The use of FS lasers in ocular surgery peaked then faded in popularity over
the past 10 years.
c. FS lasers are used to create corneal flaps in LASIK, corneal incisions in
cataract surgery and lenticule creation in the SMILE procedure.
d. FS lasers are high-energy, high-speed lasers that can be used to improve the
precision of ocular surgery.
10. Which statement is accurate regarding the surgical options for correction of
astigmatism?
a. Surgical correction of astigmatism is not relevant during cataract surgery.
b. Correction of even small amounts of astigmatism is important in refractive
surgery.
c. The ability to correct mild to severe astigmatism has improved significantly
over the past 20 years.
d. Both b and c.
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By submitting this answer sheet, I certify that I have read the lesson in its entirety
and completed the self-assessment exam personally based on the material presented. I have not obtained the answers to this exam by fraudulent or improper means.
Signature: ________________________________________ Date: _____________
Please retain a copy for your records.
LESSON 113633, RO-RCCL-1116
REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
23
CASE REPORT BY BRIAN CHOU, OD
Solving Scleral Contact Lens
Induced Pingueculitis
The simplest option is often the best solution.
A B ST R AC T
This case report describes the steps taken to solve
scleral lens-induced pingueculitis in a keratoconus
patient by refitting the patient into a smaller
diameter scleral lens. A discussion ensues on other
possible treatments, including lens notching, micro
vaults, increasing lens diameter and hybrid lenses.
Keywords: Pinguecula, pingueculitis, scleral lens,
contact lenses, keratoconus
INTRODUCTION
Keratoconus is the prototypical, naturally-occurring condition typified by elevated lower and higher-order aberrations due to a distorted cornea.1 The
primary treatment for visual rehabilitation is a rigid
contact lens to re-establish a smooth refracting surface so the tear lens underneath optically neutralizes
the aberrations resulting from the irregular corneal
surface.2 Although a simple concept, it is frequently
undermined by a host of factors, including: inability
to sustain comfortable lens wear; difficulty with lens
handling; poor ocular physiology, such as corneal
abrasions,3-9 corneal staining and other epitheliopathy, vascularized limbal keratopathy or DuBois ring;
and lens dislodgement and ejection.
Scleral contact lenses have gained popularity as an
effective treatment to restore vision in keratoconus
and other thinning disorders, including in patients
who have previously failed in traditional corneal
gas permeable (GP) and hybrid contact lenses.3,4
Patients wearing scleral lenses often report excellent
comfort, most likely because the lenses vault the
sensitive cornea and rest on the relatively insensitive
conjunctiva and underlying sclera.3,5,6
A common challenge to successful scleral lens wear
is the presence of a pinguecula on the conjunctiva,
which may mechanically interact with the landing
area of the lens, causing redness and discomfort.7,8
In one study, nearly half of the population had
a pinguecula.9 While the elective contact lens
wearer can discontinue contact lens wear and use
glasses, most patients with keratoconus require the
functional vision that only rigid-surface contact
lenses can provide. The prospect of excellent vision
at the cost of eye redness and discomfort is not
acceptable—nor is poor vision with a comfortable,
white eye. However, keratoconus patients with
pingueculitis due to scleral contact lens wear can
often remain in this modality with appropriate lens
modification.
CASE REPORT
History
A 39-year-old Caucasian male presented on referral for keratoconus
care after relocating from another
city. He reported wearing a contact lens (SynergEyes ClearKone)
only in the right eye. He indicated
an inability to tolerate wearing
any contact lens in his left eye,
including a corneal rigid lens, piggyback system with a corneal rigid
lens and various hybrid contact
lenses. He did not use any eyeglasses. Family ocular history was
unremarkable, he denied taking
any regular medication and had
no known drug allergies. He had
no previous ocular surgery, and
general health was unremarkable.
Diagnostic Data
Unaided visual acuity was
20/100 OD and 20/400 OS.
Autorefraction yielded readings
of -2.50 -5.25X066 OD and no
obtainable measurement OS.
Manifest refraction was -2.506.00X065 OD yielding 20/30, and
24 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
gave no improvement OS. Corneal
topography showed asymmetric
corneal steepening OU, with significant irregularity, especially OS
(Figure 1).
Contact lens evaluation of his
SynergEyes ClearKone lenses OU
ABOUT THE AUTHOR
Dr. Chou is a partner at
EyeLux Optometry in San
Diego, CA, where he directs
a referral-based keratoconus
clinic.
CASE REPORT
was performed, including assessment of his left lens, which he did
not wear due to discomfort. High
molecular weight fluorescein was
applied and showed an optimal
fluorescein pattern OD with good
centration and approximately 150
microns of central vault, and an
alignment relationship over the
inner landing zone (ILZ). The fluorescein pattern OS showed hard
apical bearing with inferior decentration, with an alignment relationship over the ILZ and no skirt
fluting. Contact lens acuity was
20/25 OD with spherocylindrical
overrefraction of +0.75-0.75X140
yielding 20/20, and 20/25 OS with
spherical overrefraction of -0.50
DS yielding 20/25+.
Biomicroscopy revealed that
lids and lashes were normal, while
the conjunctiva and sclera were
unremarkable with no obvious
conjunctival elevations. The right
cornea showed iron deposition
(Fleischer’s ring) and no apical
scarring. The left cornea also
showed a Fleischer’s ring, grade 2+
apical scarring and vertical folds
at the level of Descemet’s (Vogt’s
striae). Anterior chambers were
deep and quiet, and the irides were
healthy with normal anatomy.
Dilated examination was performed using a 78D condensing
lens and biomicroscope, and using
a 20D condensing lens with binocular indirect ophthalmoscopy.
Crystalline lenses were clear, and
anterior vitreous showed no liquefaction. Optic nerves were healthy
with full neuroretinal rim tissue
with C/D ratios of 0.2. Retinal
vasculature, maculae and retinal
peripheries were normal as well.
Diagnosis
I diagnosed keratoconus OS > OD
with contact lens discomfort OS
attributable to the pronounced
corneal distortion causing me-
Fig. 1. Topography showing corneal irregularity, more in the left than right eye.
chanical interaction with the
hybrid lens.
Treatment
I did not prescribe glasses because
the patient rejected the manifest
refraction when in a trial frame. I
conveyed information about the
eye disease, including how significant progression was unlikely at
his age, as keratoconus is known
to arrest on its own by the third to
fourth decade of life.10
I recommended prescribing
scleral contact lenses for both eyes
and he scheduled a diagnostic
fitting visit.
When he returned for diagnostic
lens fitting, I started with Jupiter
scleral lenses (Visionary Optics).
The following initial lenses were
applied with fluorescein (NaFl):
OD: 7.50mm base curve,
-5.00D power, 18.2mm
diameter, standard peripheral
system.
OS: 6.25mm base curve,
-14.00D power, 18.2mm
diameter, standard peripheral
system.
The NaFl pattern OD showed
excessive central bearing. Overrefraction was not performed. OS
showed optimal fitting characteristics with good centration and
approximately 250 micron central
clearance extending toward the
limbus and a scleral landing
zone without any noted vascular
blanching or edge lift. Spherical
overrefraction OS was +1.00DS
yielding 20/25.
A new right diagnostic lens with
greater sagittal depth was applied
with 7.18mm base curve, -7.00D
power, 18.2mm diameter and
standard peripheral system.
This lens showed an optimal
NaFl pattern with slight inferotemporal decentration, approximately 250 microns of central
clearance and light superonasal
touch in the corneal periphery.
The scleral landing zone appeared
ideal without vasculature blanching or edge lift. Spherical over-refraction was -0.25DS yielding
20/25+.
The final scleral lenses had the
following parameters:
OD: 7.18mm base curve,
-7.25D power, 18.2mm
REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
25
CASE REPORT
Dispensing and Training Visit
Roughly two weeks later, I
dispensed the scleral lenses and
trained him on proper application,
removal and lens care.
Contact lens acuity was 20/25+
with a spherical overrefraction of
plano DS in each eye. A cursory
evaluation using biomicroscopy showed a contact lens fitting
relationship consistent with what
I expected from the previous visit
without air bubbles OU. He was
cleared to wear his new contact
lenses up to full waking hours, if
well tolerated, and asked to return
for a contact lens progress visit in
one to two weeks.
left lens showed centration with
approximately 250 microns of
central clearance with a relatively
even post-lens tear film extending
toward the limbus, but mild peripheral vascular blanching at the
nasal scleral landing zone. A new
left lens was ordered with identical parameters except the scleral
landing curve was changed from
14.50/0.5 to 15.50/0.5.
When he returned to exchange
his existing OS scleral lens for the
new lens, visual acuity in the eye
was 20/25+ with a plano overrefraction. The new lens showed
an improved fitting relationship
with reduced nasal peripheral
vascular blanching. There was no
noticeable decrease in the central
clearance. The patient was asked
to report back within two weeks
in the event there were any bothersome symptoms, but otherwise to
return for routine examination in
12 months.
Progress Visits
A week and a half later, he returned reporting that both new
lenses performed well with excellent vision. Comfort in the right
eye was excellent, and comfort in
the left eye had improved by 90%
compared with his previous experiences with other modalities. He
noted that there was some tolerable redness and soreness in the left
eye, especially by the end of the
day. Wearing time at this visit was
four hours.
Contact lens acuity was 20/25+
with a spherical overrefraction of
plano DS in each eye. Fluorescein
evaluation of the right lens showed
slight inferotemporal decentration
but an otherwise optimal fitting
relationship with approximately
250 microns of central clearance
and relatively even post-lens tear
film distribution, but light superonasal peripheral touch. The
Annual Examination with
Contact Lens Evaluation
When he presented the next year
for his routine examination, he
reported doing overall quite well
wearing scleral contact lenses.
However, he noted in the past one
to two months the nasal conjunctival area of his left eye was red and
sore. He stated that it was mostly
a cosmetic issue and that on some
occasions he would only wear the
right scleral lens. Personal health
history was unchanged with no
regular medication and no known
medication allergies.
Contact lens acuity was 20/25
OD with an overrefraction of
-0.50D giving 20/25+, and 20/25+
OS with a plano overrefraction
OS.
Biomicroscopy showed no
changes to the right eye from the
previous examination. However,
the left eye showed an area nasally
diameter, standard peripheral
system, Boston XO Clear with
drill dot.
OS: 6.25mm base curve,
-13.00D power, 18.2mm
diameter, standard peripheral
system, Boston XO Clear.
26 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
of raised and injected conjunctival
tissue, which was interacting with
the scleral lens edge (Figure 2).
Another Diagnosis
I diagnosed pingueculitis in the left
eye related to mechanical interaction with the nasal edge of the
scleral contact lens.
He was scheduled to return for
diagnostic contact lens prescribing
into a smaller diameter lens in the
left eye.
Treatment
When he returned for diagnostic
fitting into new scleral lenses, the
primary goal was to prescribe
a smaller diameter lens in the
left eye to reduce the amount of
mechanical interaction against
the small nasal pinguecula. The
new lens design selected for the
left eye was the 16.5mm diameter ICD scleral lens (Paragon
Vision Sciences), as this diagnostic
set was available in the office.
Concurrently, I re-prescribed the
right lens from the Jupiter design
into the Europa design (Visionary
Optics) which, according to the
manufacturer, is an improved
design with a larger optic zone,
reverse geometry mid-peripheral
reverse curve and an enhanced
haptic profile.11
First diagnostic lenses (Europa
design OD, ICD design OS):
OD: 7.18mm base curve,
-2.50D power, 18.0mm
diameter, standard peripheral
system.
OS: 6.88mm base curve,
-5.00D power, 16.5mm
diameter, standard peripheral
system, 4500 sag.
The right lens showed slight
inferotemporal decentration with
approximately 250 microns of
central clearance with some light
superonasal peripheral thinning
of the post-lens tear film. The
CASE REPORT
Fig. 2. Left eye after removal of
18.2mm diameter scleral lens
showing conjunctival injection,
especially nasally surrounding
pingueculum, and also Charleux’s
sign with retroillumination.
Fig. 3. Left eye showing resolution
of pingueculitis after the patient was
prescribed the new 16.5mm diameter
scleral lens.
scleral landing zone was optimal.
Spherical over-refraction OD was
-5.50DS yielding 20/25+. The left
lens showed centration and moderate central apical bearing. Due
to the lack of central clearance,
the following diagnostic lens with
300 microns of additional sagittal
depth was then applied:
OS: 6.62mm base curve,
-8.00D power, 16.5mm
diameter, standard peripheral
system, sag: 4800 sag.
This new left lens was centered
with approximately 150 microns
of central clearance and a relatively even post-lens tear film extending toward the limbus, with an
ideal scleral landing relationship.
Spherical overrefraction OS was
-2.25 yielding 20/25.
The following contact lenses
were ordered (Europa OD, ICD
OS):
OD: 7.18mm base curve,
-7.75D power, 18.0mm
diameter, standard peripheral
system, Boston XO Clear.
OS: 6.62mm base curve,
-10.25D power, 16.5mm
diameter, standard peripheral
system, 4800 sag, HDS100
Blue.
When he returned for dispensing
of his new scleral lenses, subjectively he reported excellent vision
and felt that the smaller left lens
was already more comfortable.
Visual acuity was 20/25+ OD
with a spherical overrefraction of
plano DS and 20/25 OS with a
spherical overrefraction of +0.50
OS yielding 20/25. Biomicroscopy
showed centered lenses with the
left lens edge sparing mechanical
interaction with the nasal pinguecula. Fluorescein evaluation was
not performed. He was asked to
return in one week for a contact
lens progress visit, and to come in
wearing his new scleral contacts
for at least an hour.
Progress Visit
When he returned for his contact
lens progress visit, he had been
wearing his lenses for three hours
and reporting that he was pleased
with the new scleral lenses. He
estimated that the redness and
discomfort in the left eye had
resolved by 98% with the smaller
diameter scleral lens. For the right
eye, there was no appreciable
subjective difference in his wearing
experience with the new design.
Subjective vision was excellent in
both eyes, with comfortable wear
for full waking hours.
Contact lens visual acuity was
20/25+ OD with spherical overrefraction of plano DS, and 20/25
OS with spherical overrefraction
of +0.50 OS yielding 20/25+.
Biomicroscopy showed the left
bulbar conjunctiva had significantly reduced injection and the
inflamed nasal pinguecula had
subsided in size (Figure 3). There
was no significant corneal staining.
Fluorescein evaluation with the
right scleral lens showed approximately 250 microns of central
clearance with a relatively even
post-lens tear film extending to the
limbal clearance zone. The scleral
landing zone was optimal. The left
lens showed approximately 150
microns of central clearance, also
with an even post-lens tear film
extending to the limbal clearance
zone. The scleral landing zone was
optimal as well.
A new left lens was ordered,
accounting for the +0.50 overrefraction, and he was released
to routine annual examination
following the lens exchange.
DISCUSSION
Pingueculae are the most common
conjunctival lesion, occurring
in 48% of patients.9 They can
mechanically interact with the
landing zone of a scleral contact lens, leading to redness and
discomfort.7,8
Although prescribing topical
corticosteroid therapy would quell
the inflammatory component of
pingueculitis, it would not eliminate the underlying mechanical interaction against the conjunctival
elevation and could require chronic dosing. The risk of chronic corticosteroid therapy, even with the
ester-based corticosteroid loteprednol, is the potential for cataract
formation and increased IOP.12 For
this reason, although suitable as a
REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
27
CASE REPORT
Photo: Alden Optical
periodic adjunct, a more sensible
approach is modifying the lens to
address the root cause of scleral
lens–induced pingueculitis.
A review of the literature describes lens-based modifications,
such as adding an edge notch
on the scleral lens to resolve the
problems with pingueculae.7,8,14
However, because these edge
notches are introduced using a
hand tool, there is variability with
lens reproducibility. MicroVaults
(Alden Optical)—designed and
manufactured with CAD/CAM
technology—may overcome the
problems of reproducibility found
with traditional hand-notching,
according to the manufacturer.
(Figure 4).15 With both handnotched lenses and MicroVaults,
the patient must apply the notches
in the proper orientation to correspond with the location of the
pinguecula.
Finally, although not the case
with this patient, hybrid lenses may afford resolution of the
mechanical interaction on the
pinguecula due to draping of the
soft skirt over the conjunctival
elevation.
As illustrated by this case report,
ordering a smaller diameter scleral
lens was a simple and effective
treatment for this patient’s pingueculitis, particularly because it was
peripherally located. The benefit
of decreasing lens diameter is that
it is simple, can minimize further
cost to the patient, and removes
the burden of applying the lens
with the notch or MicroVault in
the same location of the pinguecula. While decreasing diameter may
seem an intuitive solution, interestingly, another purported strategy
is to prescribe an even larger diameter scleral lens to compress the
pinguecula.13
Scleral contact lenses are very
well tolerated by most patients
Fig. 4. Just like scleral lenses with an edge notch, MicroVault lenses require
lens application with rotational registration such that the MicroVault aligns
with the conjunctival elevation.
with keratoconus due to good
comfort and vision, especially
when compared to corneal gas
permeables and other types of
contact lenses.6 The high rate of
success of scleral lenses should
remind clinicians to educate
those with keratoconus about the
importance of ultraviolet (UV)
light protection to minimize the
risk of developing pingueculae.
Although the aforementioned
modifications to scleral lenses can
help patients with pingueculae
to remain in scleral lens wear, it
is best if patients never develop
these conjunctival lesions in the
first place. Although UV light may
have a therapeutic effect in mitigating keratoconus progression by
facilitating collagen crosslinking,
it is likely outweighed by the risks
of UV exposure, including certain
eyelid growths, pingueculae, pterygia, cataract and retinal damage.16
S
cleral contact lenses are well
tolerated by most keratoconus
patients, but conjunctival lesions,
including pingueculae, can pose an
obstacle to success. For some patients, reducing the lens diameter
to eliminate or reduce interaction
of the lens edge with the conjunctival lesion—especially if the lesion
is located peripherally—is the simplest treatment option. Conversely,
for others with pingueculae,
enlarging the scleral lens diameter to deliberately compress the
conjunctival elevation may help. If
28 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
these treatments are unsatisfactory, edge notching and MicroVaults
are the next logical step, which
involves greater complexity due to
additional position specification of
these lens modifications.
RCCL
1. Alió JL, Shabayek MH. Corneal higher order aberrations: a method to grade keratoconus. J Refract
Surg. 2006;22(6):539-45.
2. Barnett M, Mannis MJ. Contact lenses in the management of keratoconus. Cornea. 2011;30(12):1510-6.
3. Schornack MM, Patel SV. Scleral lenses in the
management of keratoconus. Eye Contact Lens.
2010;36(1):39-44.
4. Van der Worp E, Bornman D, Ferreira DL, et al.
Modern scleral contact lenses: A review. Cont Lens
Anterior Eye. 2014;37(4):240-50.
5. Visser ES, Visser R, van Lier HJ, et al. Modern
scleral lenses part II: patient satisfaction. Eye Contact Lens. 2007;31(1):21-5.
6. Bergmanson JPG, Walker MK, Johnson LA.
Assessing scleral contact lens satisfaction in a keratoconus population. Optom Vis Sci. 2016;93(8[Epub
ahead of print].
7. Messer M. Getting creative with scleral lenses: Part
1. Review of Cornea & Contact Lenses. 2012;148(1):7.
8. Denaeyer GW. Designing lenses to work around
scleral obstacles. Contact Lens Spectrum. August
2012. Available at www.clspectrum.com/articleviewer.aspx?articleID=107286. Accessed May 24, 2016.
9. Viso E, Gude F, Rodríguez-Ares MT. Prevalence of
pinguecula and pterygium in a general population in
Spain. Eye (Lond). 2011;25(3):350-7.
10. Rabinowitz YS. Keratoconus. Surv. of Ophthalmol. 1998;42:297–319.
11. Visionary Optics. Europa Scleral Overview.
Available at www.visionary-optics.com/products/
scleral-lens-for-irregular-corneas/europa-scleral.
Accessed May 30, 2026.
12. Comston TL, DeCory HH. Advances in corticosteroid therapy for ocular inflammation: loteprednol
etabonate. Int J Inflam. 2012;2012:789623.
13. Barnett M. Case study: scleral lenses post glaucoma surgery. Optometric Management. December
1, 2014. Available at www.optometricmanagement.
com/articleviewer.aspx?articleID=112072. Accessed
May 24, 2016.
14. Messer B. Utilizing MicroVaults to improve
comfort and cosmesis in scleral lens wearers with
pingueculae. Poster. Available at www.aldenoptical.
com/docs/zenlens/Zenlens_Poster.pdf. Accessed
May 24, 2016.
15. Van der Worp E. A guide to scleral lens fitting,
Version 2.0 [monograph online]. Forest Grove, OR:
Pacific University; 2015:51. Available from: http://
commons.pacificu.edu/mono/10/.
16. Behar-Cohen F, Baillet G, de Ayguavives T, et al.
Ultraviolet damage to the eye revisited: eye-sun protection factor (E-SPF®), a new ultraviolet protection
label for eyewear. Clin Ophthalmol. 2014;8:87-104.
Advances in Understanding
Tear Film Dynamics
Let’s gain some perspective on the components, modalities and methodology of dry eye.
By Will Smith, OD
D
ry eye disease (DED)
is a massive but often
under-appreciated
problem. Data suggests as many as 35%
of Americans have some degree of
DED.1,2 While there is a surfeit of
information on DED treatment,
diagnosis and observation seem to
be the more challenging aspects.
The ocular tear film is often
observed, but rarely qualified.
This qualification is one of the
most challenging parts of managing DED. The ocular tear film
provides lubrication and visual
clarity and is also the first barrier
of protection for our eyes. Any vehicle is markedly limited without
a windshield, but if the windshield
it has is covered in dirt or mud, it
is useless.
Knowing the anatomical characteristics of the tear film builds
the framework for a better understanding of ocular surface disease.
TEAR FILM ANATOMY:
A REFRESHER
All clinicians know that the tear
film is comprised of three dynamic
layers—mucin, aqueous and lipid—but some of its specifics may
elude us in routine practice. The
mucin layer is 0.02µm to 0.05µm
thick and provides an anchor for
tear film foundation, while the
aqueous layer resides between
both mucin and lipid layers and is
the thickest layer, at 0.7µm. The
most superficial is the lipid layer,
which helps protect the tear film
from decomposition.3
Tears are produced from the
lacrimal gland under the influence
of the parasympathetic and sympathetic nervous system.4 Through
dynamic tear film interferometry
we know tear fluid is spread over
the ocular surface from temporal to the nasal segments of the
eye.5,6 The distribution of tears
is dependent on lid blink, and
facilitation of drainage is through
the lacrimal puncta.5,7 The tear
film takes one of three outputs:
evaporation, drainage or absorption. Evaporation is inevitable,
but accelerated by poor lipid tear
layer.8 Drainage through the nasolacrimal system can be impeded
by anatomical morphology such as
scarring or cautery. Absorption is
suggested through corneal permeability in the absence of compromised corneal function and is
reported as minimal, roughly 15%
absorption.9,10
Collectively, the tear film
supplies the ocular surface with
many nutrients and wound healing
properties such as fibronectin,
vitamins and growth factors.11
These elements support and modulate proliferation, migration and
differentiation of the conjunctival
and corneal epithelium.
AQUEOUS-DEFICIENT VS.
EVAPORATIVE DED
The Dry Eye Workshop defined
two modalities of DED: aqueous
deficient and evaporative.12 Of
these two subcategories, evapora-
tive dry eye represents the majority of cases.13,14 Evaporative dry
eye disease, which results from
increased ocular surface exposure
and meibomian gland dysfunction
(MGD), is commonly associated
with an inflammatory process.12
During inflammation, proteins
are released into the tears, which
serve to support opsonization
(i.e., targeting) and phagocytosis
of microbes by macrophages and
lymphocytes. Ultimately, damage
to the meibomian or sebaceous
glands comes from androgen dysregulation, microbe invasion and
excretory duct obstruction due to
hyperkeratinization and increased
viscosity of meibum.15,16 Tears
serve a lubricating and mechanical
clearance function, but also possess epitheliotropic and antimicrobial properties.17,18
The importance of identifying
these underlying processes and
how they contribute to tear film
ABOUT THE AUTHOR
Dr. Smith is an optometric
physician with a special
interest in dry eye
management, therapeutic
contact lenses and surgical
comanagement. Currently,
he practices at the Veterans
Affairs outpatient clinic in
Jacksonville, VA, where there is
great demand for emergency eye care and
management of chronic ocular disease. Dr.
Smith has served as a board member and
volunteer for many organizations, including:
Volunteer Optometric Services to Humanity
(VOSH), Jefferson County Community
Participation Board and Equal Access
Birmingham. He is a member of Florida
Optometric Association and American
Optometric Association and is a National
Association of Veterans Affairs optometrist.
REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
29
ADVANCES IN UNDERSTANDING TEAR FILM DYNAMICS
Fig. 1. Transillumination of lower lid, showing meibomian gland structure with
blue and white arrows.
dysfunction cannot be overstated.
Diagnostic tools have advanced to
allow proper quality assessment
of tear film dynamics, and they
help to standardize a protocol for
diagnosis and management.
OBSERVING THE GLANDS
Meibomian gland observation
can be performed by meiboscopy,
interferometry and meibography.
Meiboscopy is performed with
basic transillumination of the lids
(Figure 1).20 Although this method
is quick, effective and available to
all practitioners, newer techniques
and tools provide better visualization of meibomian gland structure.
Meibography allows for the
evaluation of the number and
morphology of the meibomian
glands from their point of origin
through to the ductal termination
at the orifices (Figure 2). There are
two principles in meibography:
transillumination of the everted lid and direct illumination,
or non-contact meibography.
Slit-lamp microscopy (Topcon),
portable noncontact meibography (Shenzhen LYD Technology),
LipiScan (TearScience), LipiView
II (TearScience) and Keratography
5M (Oculus) are all instruments
designed to perform meibography.
Only gross imaging scales exist
for grading at this time (Figure
3).21 Although rudimentary, they
are effective in documenting
baseline meibomian status by
comparing the patient’s gland
structure with the closest associated grading. Studies show methods
of grading meibography images
demonstrate good within-reader
reliability and fair between-reader reliability.22 Researchers observed normal aging changes of
meibomian glands such as acinar
(glandular) density reduction and
an evident decrease of the acinar
diameter without significant modifications of the glandular orifice
diameter.23 They also observed
morphological changes in disease
states; with MGD, acinar density
was reduced but diameter was increased, and orifice diameter was
dilated.23
Interferometry allows for micro
observation of the tear film’s lipid
layer. Basic optical theory of reflectance and thin film interferometry can indicate the hue and saturation seen as a function of the
thickness of the transparent layer,
causing the interference phenomena.24 Lipiview II (TearScience) is
the only commercial instrument
designed to provide real-time visualization of the lipid layer thickness, lid closure and blink rate
with one scan. Research shows a
thin lipid layer correlates with dry
eye disease symptoms.25
HYPEROSMOLARITY
Tear film hyperosmolarity is considered by some researchers to be
the primary cause of discomfort,
30 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
ocular surface damage and inflammation in dry eye.26 Osmolarity
can be measured with TearLab’s
handheld osmometer. A clinical
cut-off of 312mOsm is suggested
as the diagnostic level for aqueous-deficient and evaporative dry
eye.27 Any decrease in meibum or
aqueous secretion contributes to
increases in osmolarity, thus complicating diagnostic specificity.
Researchers evaluated whether
tear film osmolarity could be used
as a reliable diagnostic tool for
dry eye in patients with rheumatoid arthritis (RA). They found
that 66% of patients with RA
have osmolarity of greater than
316mOsm, serving as an indication for work-up of systemic
inflammatory diseases.28
Matrix metalloproteinase-9
(MMP-9)—a nonspecific marker
of inflammation—is a proteolytic enzyme that comes from
stressed epithelial cells on the
ocular surface.29 In healthy control
individuals, MMP-9 is normally
found at low levels; however, in
those with DED, levels rise to
more than 40ng/ml.29,30 MMP-9
can be measured by InflammaDry
(Rapid Pathogen Screening, RPS).
To perform this point-of-care test,
swab the palpebral conjunctiva,
and place the swab into the RPS
Fig. 2. Meibography of normal gland
structure (top) and gland truncation
or scarring (bottom).
Questionnaire
Osmolarity
(TearLab)
Interferometry
InflammaDry
(RPS)
Meibography
Schirmer's
Slit Lamp
Exam
(Careful lid
evaluation)
Staining
Fig 4. Example of an ocular surface work-up protocol.
cassette, where a buffer is applied
to complete the test.
Although eye care practitioners
have long been able to identify dry
eye patients by clinical observation of ocular surface disruption,
osmolarity and MMP-9 testing—
particularly when used in combination—increase the precision we
can bring to our assessment and
management plan.
Meiboscale
Area of Loss
Fig. 3. Five-grade meiboscale.14
STANDARDIZED PROTOCOL
Diagnostic technologies still lack
the ability to determine the ideal
course of disease management—
that remains a clinical responsibility. As providers, we seek certainty
to provide the most targeted and
cost effective care. Not all technologies provide equal value, but all
increase our knowledge.
The best strategy with DED
testing is to keep follow-up care
consistent with a standardized
protocol (Figure 4) that provides
information about tear production, ocular surface grade and
meibomian gland function.
RCCL
1. Improving screening, Diagnosis, And Treatment
of Dry Eye Disease: Expert Recommendations
From the 2014 Dry Eye Summit. National Eye
Institute. Facts about dry eye. Availabe at www.
nei.nih.gov/health/dryeye/dryeye. Accessed
September 7, 2016.
2. The Epidemiology of Dry Eye Disease: Report
of the Epidemiology Subcommittee of the International Dry Eye WorkShop. 2007;5(2):93-107.
3. Creech J, Do L, Ratt I, Radke C. In vivo tear
film thickness and implications for tear film stability. Curr Eye Res. 1998 Nov;(11):1058-66.
© 2012, 2016 Dr. Heiko Pult — Optometry & Vision Research, Germany,
www.heiko-pult-de, used with permission.
4. Dartt DA. Dysfunctional neural regulation
of lacrimal gland secretion and its role in the
pathogenesis of dry eye syndromes. The Ocular
Surface. 2004;2:76-88.
5. Clinch TE, Benedetto DA, Felberg NT, Laibson
PR. Schirmer’s test. A closer look. Arch Ophthalmol. 1983;101:1383-6.
6. Doane MG. An instrument for in vivo tear film
interferometry. Optom Vis Sci. 1989;66:383-8.
7. Tsubota K. Tear dynamics and dry eye. Prog
Retin Eye Res. 1998;17:565-96.
8. Lozato PA, Pisella PJ, Baudouin C. The lipid
layer of the lacrimal tear film: physiology and
pathology. J Fr Ophtalmol. 2001;24(6):643-58.
9. Joshi A, Maurice DM, Paugh JR. A new method
for determining corneal epithelial barrier to
fluorescein in humans. Invest Ophthalmol Vis Sci.
1996;37:1008-16.
10. Goebbels M, Spitznas M. Corneal epithelial permeability of dry eyes before and after
treatment with artificial tears. Ophthalmology.
1992;99:873-8.
11. Geerling G, MacLennan S, Hartwig D. Autologous serum eyedrops for ocular surface disorders. Br J Ophthalmol. 2004;88(11):1467–74.
12. The definition and classification of dry eye
disease: report of the Definition and classification Subcommitee of the International Dry Eye
WorkShop. Ocul Surf. 2007;5(2):75-92.
13. Shimazaki J, Sakata M, Tsubota D. Ocular
surface changes and discomfort in patients with
Meibomian gland dysfunction. Arch Ophthalmol.
1995;113:1266-70.
14. Lemp M, Crews L, Ron A, et al. Distribution
of aqueous deficient and evaporative dry eye in
a clinic-based patient population. Cornea. 2012
May;31(5):472-8.
15. Gilbard JP. The diagnosis and management of
dry eyes. Otolargngol Clin N Am. 2005;38;5:87185.
16. Thody AJ, Shuster S. Control and function of
sebaceous glands. Physiol Rev. 1989;69:383-416.
17. Sullivan D, Sullivan BD, Ullman MD, et al. Androgen influence on the meibomian gland. Invest
Ophthalmol Vis Sci. 2000;41:3732-42.
18. Ng V, Cho P, Mak S, Lee A. Variability of
tear protein levels in normal young adults:
between-day variation. Graefes Arch Clin Exp
Ophthalmol. 2000;238:892–9.
19. Liu S, Richards S, Lo K, et al. Changes in gene
expression in human meibomian gland dysfunction. Inv Ophthmol Vis Sci. 2011;52:272-4.
20. Tapie R. Etude biomicroscopique des glandes
de meibomius. Ann Oculistique. 1977;210:637–48.
21. Pult H, Riede-Pult B. Neues zur Meibographie.
Die Kontaktlinse. 2011;6:24–5.
22. Nichols JJ, Berntsen DA, Mitchell GL, Nichols
KK. An assessment of grading scales for meibography images. Cornea. 2005;24:382–8.
23. Fasanella V, Agnifili L, Mastropasqua R, et al.
In vivo laser scanning confocal microscopy of
human meibomian glands in aging and ocular
surface diseases. Biomed Res Int. 2016;7432131.
24. Doane M, Lee E. Tear film interferometry as
a diagnostic tool for evaluating normal and dryeye tear film. In: Lacrimal gland, tear film, and
dry eye syndromes 2. 1998;438:297-303.
25. Tomlinson A, Khanai S. Assessment of
tear film dynamics: quanification approach.
2005;3(2):81-95.
26. Blackie CA, Solomon JD, Scaffidi RC, et al.
The relationship between dry eye symptoms and
lipid layer thickness. Cornea. 2009;28(7):789-94.
27. Gilbard JP, Farris RL, Santamaria J 2nd. Osomolarity of tear microvolumes in keratoconjunctivitis sicca. Arch Ophthalmol. 1978;96:688-91.
28. Schargus M, Wolf F, Tony H, et al. Correlation
between tear film osmolarity, dry eye disease,
and rheumatoid arthritis. Cornea. 2014;33:125761.
29. Chotikavanich S, de Paiva CS, Li de Q, et al.
Production and activity of MMP-9 on the ocular
surface increase in DTS. Invest Ophthalmol Vis
Sci. 2009;50:3203-9.
30. Acera A, Rocha G, Vecino E, et al. Inflammatory markers in the tears of patients with OSD.
Ophthalmic Res. 2008;40:315-21.
REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
31
Practice Progress
By Mile Brujic, OD, and Jason Miller, OD, MBA
Breaking Habits
Remain current with technological advancement so your patients and practices can thrive.
W
hile new
technology
is exciting at
first glance,
it often fails
to make a lasting impact in our
practices. Many of us forget about
new technological advancements,
falling back into our comfort zone,
particularly with contact lens
fits. But early adopters to change
will develop the culture of “being
ahead of the curve” and reap the
rewards of increased revenue for
that technology.
Many of us have heard the
phrase, “if it’s not broke, don’t
fix it.” While that holds true for
some scenarios, it’s not always the
smartest approach to contact lens
fitting. It’s worth taking a broader perspective that incorporates
technological advancement when
addressing certain contact lens
situations. You may find a better
way of doing things. This month,
we look at two cases and discuss
ways to break some habits many
of us may have developed over
time—regardless of efficacy.
CASE 1: CHILDREN AND
CONTACT LENSES
A 10-year-old male patient wants
to start wearing contact lenses. His
myopic correction has just jumped
from a -1.00DS OU to a -2.00DS
OU in the past eight months.
Old habits. The most familiar
method for this case would be
to discuss the various options of
contact lenses—from dailies to the
reusable two-week or one-month
modalities. After that discussion,
let the parents decide what they
think would work best for their
child. Without any information on
the differences between CLs, most
patients would choose the least
costly modality.
New habits. If, on the other
hand, we incorporate a broader
End-of-day dryness and limbal injection from significant digital device use
demonstrates signs of contact lens-related complications.
32 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
perspective and take into account
the current state of technology, we
would start with making a strong
recommendation for the new,
innovative daily disposable lenses.
Research demonstrates that three
in five contact lens wearers do not
wash their hands prior to handling the lenses.1 The minimized
handling that comes with daily
disposable lenses is just one reason
they are the healthiest and most
convenient choice and are now
considered the lens of choice for
this younger population.
Next, consider taking a step
further to discuss contact lenses
for myopia control. It is proving
worth our time to educate patients (or their parents) on certain
contact lens options now available
that are beneficial for slowing
refractive changes at a young age.
Myopia control contact lenses
offer much promise and may be
the next big thing in the contact
lens industry.
This area is one of untapped
potential and could form the foundation for future treatments for
children with developing myopia.
Many studies are currently looking
at the possibilities, but if we could
tell parents they could reduce their
child’s vision impairment by a certain percentage (working toward
a design or treatment that would
reduce myopia by 50%), that
would be a drastic improvement
worth exploring.
These lenses work by slowing
down the patient’s predicted axial
length elongation. Through a complicated process, the peripheral
retina can mediate refractive development centrally. The peripheral
Photo: Paul M. Karpecki, OD
Dryness from incomplete blinks can
happen at any age, especially for
digital device users.
hyperopia can be a stimulus and
may even precede the development
of myopia. Current theories are
aimed at preventing this peripheral
defocus at an early age.2 Questions
obviously remain, but many researchers are evaluating the role of
genetic predisposition, amount of
near work, lag of accommodation,
vitamin D levels and the amount
of time spent outdoors.3,4
Other new treatments such as
light filtering spectacle lenses,
soft or rigid bifocal or multifocal
contact lenses, orthokeratology
lenses and pharmaceutical agents
(atropine, pirenzepine, 7-methylxanthine) are under thorough
evaluation.
As eye care professionals, we
see similar cases on a daily basis.
Having the tools, technology and
research to back up our recommendations is critical. Don’t get
stuck in the same old habits or
wait too long.
CASE 2: DIGITAL
DEVICE USER
A 30-year-old female patient is
currently wearing monthly disposable contact lenses and wants to
renew her contact lens prescription. She says she is happy with
her current lenses.
Old habits. The most familiar
route would consist of performing
the examination, checking the
patient’s refraction and renewing
the same prescription. Rather than
trying to upgrade the patient into
a newer contact lens technology, it is often quicker and easier
to just renew the prescription if
everything looks up to par and the
patient has no complaints. This is,
unfortunately, the more common
approach in many offices.
New habits. If we want to
remain ahead of the curve and
consider the best option available
to us, we should start by getting
the whole story. Upon further
questioning, you find out that
this patient works at a bank and
spends eight to 10 hours a day on
the computer. She has intermittent
blurriness (due to a reduced blink
rate and incomplete blinking)
throughout the day and her eyes
look red at the end of the day. The
general consensus, after a more
thorough session, would be that
our patient’s current contact lens
regimen is not, in fact, good at all.
As a result of extensive digital device use, today’s patients
put new visual health demands
on their eyes. Despite all of the
advances in contact lens technology, patient discomfort remains
a problem. Many are reticent to
complain and would rather continue with what they have than deal
with alternatives. Patients often
imagine the worst, and so avoid
confronting the idea of change.
This case provides a great oppor-
tunity to upgrade the patient into
more technologically advanced
contact lenses. Patients need a contact lens that can provide all-day
visual clarity and comfort.
Instead of providing the same
contact lens prescription, consider
refitting this patient in a newer
design and modality. Many new
daily disposable contact lenses
have moisture agents embedded
in the matrix of the contact lens
to help reduce end-of-day dryness
and improve all-day comfort.
Additionally, consider using a lens
that provides improved optical
correction while on the computer.
This may be an aspheric or a low
multifocal design to help with the
accommodative demand throughout the day.
E
ye care professionals can
choose from a wide variety
of contact lens materials, designs
and modalities that can improve
ocular health and visual clarity.
Innovative products and research
will continue to drive the market.
It is vital we stay current with
ongoing research in an attempt
to break old habits and integrate
new and improved methodologies
into our practices—a shift that is
sure to provide improved health
to our patients and growth to our
practices.
RCCL
1. Stone R. The importance of compliance:
focusing on the key steps. Poster presented at
the annual meeting of the British Contact Lens
Association; May 31-June 2, 2007.
2. Mutti DO, Sholtz RI, Friedman NE, Zadnik K.
Peripheral refraction and ocular shape in children.
Invest Ophthalmol Vis Sci. 2000:41(5):1022-30.
3. Mutti DO, Marks AR. Blood levels of vitamin D in
teens and young adults with myopia. Optom Vis
Sci. 2011;88:377-82.
4. Mutti DO, Mitchell GL, Sinnott LT, et al. Corneal
and crystalline lens dimensions before and after
myopia onset. Optom Vis Sci. 2012;89:251-62.
REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
33
Out of the Box
By Gary Gerber, OD
Four Keys to Building Your Practice
These commonalities indicate you are ready to venture out on your own—and that you
will be successful when you do.
O
ver the last few years,
our consulting company has helped an
array of doctors start
their own practices.
Many are transitioning from corporate to private practice, while others
are working for ODs and are now
ready to venture out on their own.
Looking back on these practices
and seeing what they did to become
successful made me realize they all
had four things in common:
1. BUILD A STRONG BRAND
They know who they are and what
they want. More specifically, they
have a strong brand, mission and
optical providers offer frames not
readily found elsewhere, making the
buying experience distinctive.
2. BECOME A GREAT LEADER
These doctors are great leaders.
Many are naturals, but most aren’t.
Rather, most became great leaders
by staying hyper-focused on their
brands to ensure every employee is
keyed in to the specific nature of the
practice. So, instead of just holding
a staff meeting and saying, “We are
going to change the way we book
appointments from Y to Z,” they
use this as a brand teaching moment: “Because our brand is about
X, and because every decision and
GET FOCUSED, EMPLOY A TEAM
INVESTED IN YOUR BRAND AND
REMAIN APPROACHABLE—THEN
WATCH YOUR PRACTICE THRIVE.
values. These practices unequivocally stand for something. They are
known in their communities for doing one particular thing better than
other practices. That one thing may
be clinical (specialty contact lenses,
dry eye treatment or pediatrics) or
experiential (exemplary, memorable
service; unique optical selection;
strong involvement in the community). Notably, they are willing to
perform this métier to the exclusion
of others. For example, specialty
lens practices de-emphasize eyeglass
offerings to increase referrals from
other practitioners, and pediatric
practices don’t see adults. Unique
fiber of this practice involves some
component of X, we are changing
the way we book appointments
from Y to Z.” When staff members
overhear these leaders talking to patients, sales reps, family or friends,
the brand messaging is infused in
every conversation. They set an
example of what it means to live the
brand. From that, their staff sees
an unwavering commitment to the
practice brand and values, which
results in a staff that wants to be a
part of something meaningful.
3. WELCOME CHANGE
Change is welcomed, encouraged
34 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016
and happens quickly. Staff members
are constantly challenged to offer
suggestions on how to improve the
brand. Even though most of these
practices open their doors with
only one staff member, that person
isn’t simply a robot tasked with
answering the phones and verifying insurance claims. Rather, they
are a source of new ideas—which
are always solicited and genuinely
welcomed. If that person rarely has
new ideas, they are quickly replaced.
While training new staff is never an
easy task, it’s usually easier for new
practices because of the extra time
available. Smart owners use this
downtime to train staff on technical
aspects of their own culture and
brands.
4. AVOID BUREAUCRACY
As these practices grow, they do so
with the mindful intent of avoiding
an impenetrable bureaucracy. The
owner creates a culture in which
they are always an approachable,
brand-savvy CEO without adding
barriers and layers of documents
and policies that would stunt
growth. There are fewer departments and managers in these practices than others, and their teams
work better together without the
stifling corporate structure.
T
hese four characteristics mark
successful transitions into private practice. Reviewing them can
shed light for other ODs wishing to
branch out into their own practice. Get focused, employ a team
invested in your brand and remain
approachable—then watch your
practice thrive.
RCCL
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