Download Understanding dry feeling eyes. Diagnosis and Treatment

Understanding dry feeling
eyes.
Diagnosis and Treatment
Gunter Wong, BSc(Hons)Optometry, MOptometry, PhD
Training Manager, Asia Pacific
2009.10.02-CN1396
Content – understanding dry feeling eyes
• Definition and incident
• Physiology of the eye
•Etiology and diagnosis
•Management
2009.10.02-CN1396
Dry Eye Syndrome (DES)
y y y
(
)
A team of international experts collectively defined dry eye syndrome as:
Dry eye is a multifactor disease of the tears and ocular surface
that results in symptoms of discomfort, visual disturbance, and
tear film instability, with potential damage to the ocular
surface. It is accompanied by increased osmolarity of the tear
film and inflammation of the ocular surface.1
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Reference 1. Report of the International Dry Eye Workshop. Ocul Surf April. 2007: 5(2):75.
Osmolarity
Tear hyperosmolarity may reasonably be regarded as the signature feature that
characterizes
h
t i
th
the condition
diti off ““ocular
l surface
f
d
dryness””1
Hyperosmolar levels in the tear film may transiently spike during tear instability,
resulting
g in corneal inflammation and triggering
gg
g sensory
y neurons6
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References: 1.Report of the International Dry Eye Workshop. Ocul Surf April. 2007: 5(2):119
6. Liu H. et al. A link between tear instability and hyperosmolarity in dry eye. Invest Ophthalmol Vis Sci.
2009 Aug;50(8):3671-9. Epub 2009 Mar 25
Population-based studies of dry eye1
*Different definitions of dry eye were used in each study.
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Reference 1. Report of the International Dry Eye Workshop. Ocul Surf April. 2007: 5(2):95.
5
The tear film has 2 layers
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The Lacrimal Apparatus
Function: To optimise visual clarity
• Produces tears
• Produces tear film components
• Drains
D i away ttears
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The Lacrimal Apparatus
Lacrimal Apparatus
• Principle and accessory (Kraus
and Wolfring) lacrimal glands:
produce tear fluid
p
• Goblet cells: secrete mucins
• Meibomian glands: secrete lipids
• Glands of Zeiss and Moll: secrete
lipids
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The 7 Functions of Tear Film
1)) Maintains hydration
y
of the eye
y
2) Lubricates the ocular surface
3)) Nourishes the cornea
4) Cleanses the ocular surface
5) Defends against bacterial invasion
6) Buffers the pH of the ocular surface
7) Refracts light for visual clarity
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Overview of Dry Eye Disease
Dry feeling eyes presents in 2 forms that can occur together:
• Evaporative dry eye: caused by increased evaporation of the tear film1
• Tear-deficient
Tear deficient dry eye: caused by changes in the tears themselves1
Tear film instability can be caused by
many things
Environmental factors
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Biological factors
Reference 1. Report of the International Dry Eye Workshop. Ocul Surf April. 2007: 5(2):77
Causes of evaporative dry eye
Photo courtesy of David W. Hansen, OD, FAAO
Photo courtesy of David W. Hansen, OD, FAAO
2009.10.02-CN1396
Causes of Tear-Deficient
Tear Deficient Dry Eye
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Reference 1. Report of the International Dry Eye Workshop. Ocul Surf April. 2007: 5(2):99
Inflammation and Dryy Eye
y Disease1
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Reference 1. Report of the International Dry Eye Workshop. Ocul Surf April. 2007: 5(2):85
Slit Lamp Examination
Photo courtesy of Elena Garcia Rubio, DOO
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Test of Tear Function
1. Tear break up time (TBUT)
•
Fluorescein is placed onto the ocular surface
•
The time it takes for dark areas to form is measured
•
Normal: > 10 sec (Caucasian); > 5 sec (Asian)
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Test of Tear Function
2. Schirmer’s test
•
Apply a paper strip to the lower and measure the amount of wetting
occuring over a specific time-period (e.g. 5 minutes)
•
Schirmer I (without anesthesia); Schirmer II (with anesthesia)
•
Dry Eye? < 10 mm in 5 mins (Schirmer II)
Schirmer’s Test
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Test of Tear Function
3. Phenol Red Thread
•
A 70-mm thread impregnated with phenon red is inserted into the
lowerlid for 15 seconds
•
Color changes from red to yellow when the thread absorbs the tears
•
Normal > 15 mm; dry eye < 9mm
Phenol Red
Thread
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Test of Tear Function
4. Tears meniscus
•
Can be seen resting on the lower lid
•
A height of 0.3 mm is considered normal
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Other parameters?
Maximum blink interval (MBI)
•
Area of break-up (AB)
Transient increases in tear hyperosmolarity during tear instability
caused the sensations noted by subjects
Ocular Surface Disease Index
Management of
underlying disorders
Eyelid disorders can cause dry eye disease
• Treatment of blepharitis (eyelid inflammation)

E lid scrubs
Eyelid
b

Antibacterial ointments

Steroid drops
p
Photo courtesy of David W. Hansen, OD, FAAO
• Treatment of ectropion or entropion

Blepharoplasty
Sjögren s dry eye patients are generally managed the
Sjögren's
same way as non-Sjögren’s
Photo courtesy of David W. Hansen, OD, FAAO
2009.10.02-CN1396
Natural Therapies for Dry Eye
Blinking
• Frequent blinking helps spread the tear
film evenly and combats evaporation
Hydration
• Dehydration can make dry eye symptoms
worse
Environmental changes
• Use humidifier or air filter1
• Avoid fans1
• Take breaks from the computer1
• Change contact lenses or wear less
frequently
Dietary supplements
• Omega 3 fatty acids1
2009.10.02-CN1396
Reference 1. Report of the International Dry Eye Workshop. Ocul Surf April. 2007: 5(2):173
Office Environment & Dry Eye
Eye irritations in office environment?
Prevalence & symptoms
•5-40% reported with eye irritation symptoms in office buildings
•symptoms include :
– burning
– dry
– gritty
– itchy
– scratchy
– sore
– stinging
– strained eyes
Factors associated with eye irritations in office
environments
•Humidity
•Room temperature
•Indoor air velocity
•VDU work
•Contact lens wear
•Makeup
Low relative humidity
•20% decrease of relative
humidity will increase the rate
of evaporation by 100%
High room temperature
•1ºC
1ºC d
decrease iin room ttemperature
t
was associated
i t d with
ith 19% d
decrease off
reported eye symptoms
Indoor air velocity
•High horizontal or downward air
velocity along the head region
increases evaporation of water
from the eye,
eye causing dry eye
symptoms
VDU work – Task
•Blink frequency during an active computer task with demand on
vision and hand
hand-eye
eye coordination was 69% lower than during a
passive task like watching a film on a VDU
VDU work – Monitor position
•The effect of lowering the gaze angle by 25º decreased ocular
surface area byy 7%
VDU work – Eyelid squint
Relaxation
After squint
During squint
•Squinting
S i ti att a computer
t screen may reduce
d
bli
blink
k
frequency by half
Makeup
•There
There is a significant
association between the use
of eye makeup and a thin
li id llayer off th
lipid
the ttear fil
film
Female
s using
makeup
•Oils in the eye makeup may
be able to displace the
phospholipids and influence
the formation of lipid
p layer
y on
the cornea
Franck C. Fatty layer of the precorneal film in the “office eye syndrome”. Acta Ophthalmol (Copenh)
1991;69:737-743.
Ways to reduce dry eye symptoms in office
environments
WORKSTATION
1 Relative
1.
R l ti h
humidity
idit ffrom 40% - 60%
2. Lowering room temperature may reduce tear film evaporation. The optimal
room
oo temperature
e pe a u e is
s be
between
ee 20
0a
and
d 22ºC
C
3. Avoid ventilation directed at your eyes
4. Adjust the position of the monitor. Downward gaze may minimize loss of
water from the tear film
5. Change font and font size of character displayed on the monitor to avoid
squinting
i ti
6. Remove glare source to avoid squinting
7 Alt
7.
Alternate
t b
between
t
work
k with
ith a high
hi h and
d llow d
degree off visual
i
l and
d cognitive
iti
demands
p
blinks help
p restore
8. Microbreaks everyy 1-2 minute and exercise of complete
normal tear film stability
Basic ingredients of tear supplements
• Water: replaces water loss
• Buffer: maintains pH of the solution.
Contains electrolytes
• Active ingredient: A lubricant to
reduce friction and/or a demulcent to
sooth irritated membranes. Increases
ocular
l surface
f
retention
t ti time.
ti
• Preservative: Used to prolong the
shelf life. Can be toxic to the eye.
y Not
used in all formulations.
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Eye drop strategies
Increase retention times
The main limitation of eye drops is their relatively short duration of action: they
are effective only while they remain on the eye. The most common way to
increase ocular retention is to increase viscosity,
y, so manyy manufacturers add
thickening agents. Newer viscoelastics formulations help to increase
retention times without blurring.
2009.10.02-CN1396
Reference 1.Report of the International Dry Eye Workshop. Ocul Surf April. 2007: 5(2):87
Eye drop strategies
Counteract hypertonicity
The tears of dry eye sufferers have an increased osmolarity (the concentration
of solutes in a solution) due to a hypertonic tear film1. The use of a hypotonic eye
drop
p may
y address this p
problem. Hypotonic
yp
p
products include blink intensive
tears, TheraTears and HypoTears.
2009.10.02-CN1396
Reference 1.Report of the International Dry Eye Workshop. Ocul Surf April. 2007: 5(2):87
Eye drop strategies
Avoid older generation toxic preservatives
It is
i generally
ll recognised
i d that
th t preservatives
ti
do
d cause sensitivity,
iti it especially
i ll older
ld
1
preservatives such as BAK .
A preservative free solution would be the first choice. However, new generation
‘
‘smart’
t’ preservatives
ti
such
h as P
Purite
it or OcuPure
O P
preservative
ti help
h l combine
bi th
the
best of both worlds.
2009.10.02-CN1396
Reference 1.Report of the International Dry Eye Workshop. Ocul Surf April. 2007: 5(2):165
Thank you for listening
blink and Ocupure are trademarks owned by or licensed to Abbott Laboratories, its subsidiaries or affiliates.
Systane
y
is a trademark of Alcon Laboratories Inc.;; Hyabak
y
is a trademark of Thea Laboratories;; THERA TEARS is a
trademark of Advanced Vision Research Inc.; Hypotears is a trademark of Novartis Inc.; Optrex Actimist is a
trademark of Reckitt Benckiser Ltd.; Purite is a trademark of Allergan Inc..
© 2009 Abbott Medical Optics Inc.
2009.10.02 – CN1396