HYDROGEL
TROUBLESHOOTING
University
of Missouri-School of Optometry
Contact
Lens Course
Objectives of this lecture:
1. You should be able to understand each of the
problems induced by hydrogel lenses
2. You should be able to understand the management
of these conditions
Reading assignment: Chapter 13 (pages
313-348) in Bennett/Henry Clinical Manual of Contact Lenses, 2nd Edition or 1st
edition Chapter 12 (pages 271-305).
I. Symptoms
A case history prior to the contact
lens evaluation provides the practitioner with patient symptoms which upon
further investigation may prevent future problems.
A. Reduced vision
1. With contact lenses on only
a. Lens Deposits
b. Incorrect Rx
c. Uncorrected astigmatism
d. Rotation of toric lens
e. Lenses switched
f. Defective lens
g. Dry eye
h. Inverted lens
i. Loose lens
j. Excessive tearing
k. Too steep or flat
2. Differential Diagnosis
a.
Over-refraction
b. Biomicroscopy
c. Blur constant, intermittent, recent, immediate or decreases with WT
d. Try another lens on
3. Treatment
a. New lens
b. Correct Rx
c. Refit with RGP or hydrogel toric lens
d. Lens lubricant
e. Change lens parameters
4. Reduced vision with contact lenses
and spectacles
a. Ocular
condition
b. Edema
c. Abrasion
d. Myopic creep
e. Incorrect Rx
f. Mucous from GPC
g. Irregular astigmatism
5. Differential Diagnosis
a.
Over-refraction
b. Biomicroscopy with & without lenses
c. Fluorescein evaluation
d. Subjective refraction
e. Keratometry
6. Treatment
a. EW lens on
DW basis to increase oxygen
b. Discontinue lens wear
c. Reduce wearing time
d. Correct Rx
B. Discomfort
1. Occurs upon insertion
a. Solution
sensitivity
b. Torn lens (edge or center)
c. Prism ballast toric lens
2. Occurs after lens removal
a. Abrasion
b. Infection
c. Ulcer
d. Corneal or ocular problem
3. Constant discomfort with lenses on
a. Tight lens
b. Edema with microcysts
c. Deposits (i.e., jelly bumps)
4. Sudden after a period of wear
a. Trapped
foreign body
b. Jelly bumps
5. Differential Diagnosis
a. Case
history
b. Biomicroscopy with & without lenses
c. Fluorescein evaluation
d. Look for compression ring
6. Treatment
a. Replace
lens
b. Change lens parameters (i.e., BCR, Dk)
c. Discontinue lens wear
d. Try a different type of toric lens
C. Burning
1. Generally related to solution
sensitivity or inadequate rinsing
2. Contamination of the lens with soap,
lotion, etc.
3. Cigarette smoke
4. Differential Diagnosis
a. Thorough
case history
b. Biomicroscopy
5. Treatment
a. Change
solution regimen
b. Replace the lenses if lenses can’t be purged
c. Re-educate the patient on lens care
D. Photophobia
1. Infection
2. Irritation (i.e., abrasion, trauma,
over-wear)
3. Differential Diagnosis
a. Case
history
b. Discharge?
c. Fluorescein evaluation
d. Trapped foreign body
e. Biomicroscopy
4. Treatment
a. Take necessary measures to eliminate the problem
E. Dryness - Scratchy, gritty feeling
1. Environment-related: AC, Heat, Dry
environment
2. Poor tear quality and quantity
3. Low TBUT
4. Incomplete blink
5. Pregnancy
6. Medications: Antihistamine,
anticholinergics, anti-anxiety agents, phenothiazines and oral contraceptives
7. Long-term computer use
8. Medical Conditions-Stevens-Johnson
Syndrome, Sjogrens Syndrome, Allergies
9. Differential Diagnosis
a. Case
history
b. TBUT/Rose Bengal/Lissamine Green
c. Biomicroscopy
d. Fluorescein evaluation
e. Schirmer/ Phenol Red Thread tes
f. Tear Prism
11. Treatment
a. Lens
lubricants - short-term treatment
b. Improve environment - increase humidity, change vents to blow away from
eyes, move desk, use deflectors on vents
c. Fit in low water, thick hydrogel lenses/RGP lenses or soft lens indicated
for dry eyes
d. Tolerate symptoms - if no adverse clinical signs
e. Blinking exercises
f. Conscious blinking
g. Saline soaks
h. Limit wearing time
i. Punctal occlusion
j. Discontinue lens wear
F. Itching
1. Allergy
2. GPC (will be covered in more detail
later in outline)
3. Differential Diagnosis
a. Case
history
• Is there
itching with & without the lens?
• Have they begun to use some new product (i.e., shampoo, aftershave,
cosmetics, etc.)?
• Do they have hayfever & seasonal allergies?
• How old are their lenses?
• Does the itching stop upon discontinuation of lens wear?
• Does it go away with a change in the solution regimen?
b. Evert lids
c. Type of discharge (Allergy-watery/GPC-mucous)
d. Biomicroscopy - check for conjunctival swelling (allergy) and deposited
lenses (GPC)
4. Treatment
a. Manage
problem by removing the allergy be it the lens, solution or other source
b. Cold compresses (Allergy)
G. Excessive lens movement
1. Deposited lens
2. Flat lens
3. Inverted lens
4. Differential Diagnosis
a.
Biomicroscopy
b. Evaluate movement & centration
5. Treatment
a. Replace
the lens
b. Change lens parameters - larger or steeper
c. Re-educate patient on detecting if lens is right side out
H. Halos (foggy, hazy vision)
1. Edema
2. Contaminated lens
3. Differential Diagnosis
a.
Biomicroscopy
b. Evaluate deposits or hazy lens
c. Inquire about wearing time
d. Try new lens
e. Subjective refraction
4. Treatment
a.
Discontinue lens wear
b. Wear EW lenses as DW
c. Decrease lens wearing time
d. Replace lenses
II. Signs
Clinical signs are observed by the practitioner and may or may not be observed
or detected by the patient
A. Injection (Patient symptom-Redness)
1. Grading scale
0=Not present
1=Mild conjunctival or limbal injection
2=Moderate conjunctival or limbal injection
3=Severe conjunctival or limbal injection
2. Generalized injection
a. Edema
b. Solution sensitivity
c. Tight lens
d. Foreign body
e. Deposited lens
f. Torn lens
g. Ocular pathology
h. Dryness
i. Trauma
j. Conjunctivitis
k. Allergies
l. Cigarette smoke
m. Poor night’s sleep
n. Hangover
o. Swimming pool chlorine
3. Sectorial injection
a. Torn edge
b. Adjacent to staining, erosion, ulcer
c. Trauma
d. Pinguecula, Episcleritis
4. Differential Diagnosis
a. Case
history
b. Biomicroscopy - Fit
c. Eliminate other factors
d. Fluorescein evaluation
e. Check care regimen
5. Treatment
a. Lens
lubricant
b. Change solution regimen
c. Replace lenses
d. Discontinue lens wear
e. Treat pathology
f. Increase oxygen to cornea
g. Re-educate
the patient on care and handling
h. Purge lens
i. Alter lens parameters to achieve a better fit
B. Staining
1. Refer to diagram in reading
assignment
2. Grading scale
0=No staining
1=Faint or minimal (diffuse punctate)
2=Moderate
3=Severe
3. Staining should be a routine part of
the examination
4. Peripheral Staining
a. Arcuate diffuse
to coalesced staining in periphery
b. Arcuate diffuse to coalesced staining in the inferior mid-peripheral area
(CSI smile)
c. Mid-peripheral diffuse staining inferiorly
5. Diffuse Stippling
a. Edema
b. Solution sensitivity
c. Infection
d. Deposited lens
6. Faulty Lens Removal Staining
7. Foreign body tracks
8. Torn lens or Jelly bumps
C. Edema
1. Grading scale
0=None - Cornea transparent & clear
1=Mild - A dull glass appearance of the corneal epithelium that may include
fine vacuoles/microcysts
2=Moderate - A dull glass appearance of corneal epithelium or stroma with large
numbers of vacuoles
3=Severe - Epithelial bullae and/or stromal edema (grayish white translucency
localized or diffuse)
2. Best viewed with the biomicroscope
and sclerotic scatter - use greater than 25X magnification
3. Hydrogel lens-induced edema is much
more diffuse and spread throughout the cornea with no distinct borders
4. Corneal edema of 8-10% may be
accompanied by conjunctival injection
5. Corneal edema of 6-8% produces
vertical striae (mild folds) at Descemet’s level
6. Striae are often the first
detectable sign of edema. As the edema is significant by this time, steps
should be taken to alleviate the edema
7. Striae are white lines found
centrally in the pupillary region. Differentiate from corneal nerves by: Nerves
bifurcate and can be followed to the periphery. Striae are 1-6mm in length,
only in the central area of the cornea and rarely bifurcate.
8. Treatment
a. Refit with
a lens which will provide greater oxygen to the cornea (i.e., EW hydrogel worn
DW, RGP)
b. Discontinue lens wear in moderate to severe cases
c. May use a topical hyperosmotic agent such as Muro-128 ointment
D. Tight lens
1. Too steep or too large
2. Minimal to no movement
3. Conjunctival drag - Conjunctiva can
be observed as moving with the lens - watch especially the conjunctival vessels
4. Ultrathin lenses move very little;
however, compression of the limbal vasculature is not present generally (Try
push-up test)
5. May result in a conjunctival
compression ring, engorgement & dilation of the limbal vessels outside the
lens and blanching of the vessels inside the lens edge or conjunctival
injection
6. Treatment
a. Flatter
BCR
b. Smaller diameter
E. Corneal vascularization
1. Grading scale
0=None
1=Mild congestion & dilation of the limbal vessels
2=Extension of limbal vessels less than 1.5mm from the prefitting position
3=Extension of the limbal vessels greater than 1.5mm from the prefitting
position
4=Severe - To within 3mm of the corneal apex
2. Corneal vascularization is the
result of:
a. Tight lens
b. Limbal compression
c. Edema
d. Overwear
3. Severe vascularization occurs
primarily in extreme cases of overwear and aphakic patients
4. Most frequently do not see true
vascularization, see limbal engorgement or vessels extending into the limbal
region but not actually into the cornea
5. Monitor:
a. Limbal
engorgement
b. Limbal vessels which do not curve back into the conjunctiva, but point into
the cornea
6. Draw pictures of what is seen
&/or take photos
7. Document prefitting vasculature
8. Note neovascularization, how much
and where (i.e., all quadrants, just superior or just inferior)
9. Raise that upper lid
10. Change is needed if
neovascularization is greater than 1.5mm into the cornea
F. Conjunctivitis (Allergic, viral,
bacterial)
1. Conjunctivitis may be aggravated by
CL wear
2. Lens wear should be discontinued
until conjunctivitis has cleared
3. Patients may re-infect themselves if
lenses are not properly disinfected
4. Lenses may need to be destroyed and
replaced with new ones
5. Be cautious about contaminated
solutions & cases or contaminating solutions
III. Specific Conditions related to CL
wear
A. Giant Papillary Conjunctivitis (GPC)
or Contact Lens-Related Papillary Conjunctivitis (CLRPC)
1. Usually bilateral; hoever may be
worse in one eye
2. Initially itching worse on lens
removal
3. Must evert lid & lid eversion
must be done routinely to prevent GPC from progressing
4. Best viewed with fluorescein &
cobalt blue light
5. Etiology
a.
Auto-immune response to deposits on the lens
b. Condition increases over time as lens is worn, becomes older and more
deposited.
6. Treatment
a.
Discontinue lens wear in severe cases (Grade 3 & 4)
b. Provide clean lenses
c. Use enzyme cleaner weekly or bi-weekly and surfactant cleaner daily
d. Consider Frequent Replacement/disposables
e. Refit into deposit resistant lens materials
f. Provide frequent follow-up care
g. Pharmacological Agents
{Alomide (Alcon), Crolom (B&L), Livostin, Inflamase Forte, FML, Acular,
Patanol}
B. Contact-Lens Associated Superior
Limbic Keratoconjunctivitis (CL-SLK)
1. Corneal & conjunctival changes
in the superior limbal area
2. Symptoms
a. Lens Awareness/discomfort
b. Burning
c. Itching
d. Photophobia
e. Blurred vision
f. Tearing
g. No Symptoms
3. Signs
a. Limbal
injection superiorly
b. Sub & intra epithelial infiltrates
c. Fibrovascular micropannus
d. Hazy epithelium
e. Staining of cornea & conjunctiva in that region
f. Conjunctival chemosis
4. Possible causes
a. Hypoxia in
the area covered by the lens & lid
b. Mechanical irritation of the lens
c. Preservative irritation (thimerosal)
d. Immunological response similar to GPC
5. Treatment
a. Discontinue
lens wear until all symptoms & signs have disappeared, with the exception
of vascularization (days to weeks)
b. Lubricants or ointment may be used to reduce the irritation of blinking in
that area
c. Refit the patient after signs & symptoms have disappeared
d. Monitor the patient closely
e. Recommend the use of non-preserved solutions
IV. Cases
Case 1 - Patient is a long-term
hydrogel wearer. Patient notices reduced vision with the OS and mild burning
sensation. When patient removes contact lenses, he notices that vision still
seems reduced with spectacles. Upon examination, VA is reduced to 20/80 OS and
the biomicroscope reveals a central coalesced area of staining.
Case 2 - Patient is wearing EW hydrogel
lenses. She wears them on a 5 day basis. She complains of hazy vision. What
should you be thinking of and looking for?
Case 3 - Patient complains of excess
lens movement and blurry vision. Upon examination, you see edge lift off. What
might be wrong?
Case 4 - Patient comes to your office
complaining of reduced vision OD. Over-refraction is OD -0.50D and OS +0.50D.
What may be the problem?
Case 5 - Patient has neovascularization
of 2mm superiorly and 1.5mm inferiorly. Patient has not returned for follow-up
for one year. The lens is moving adequately. What might be some questions for
you to ask him?
Case 6 - Patient is fit in hydrogel EW.
After 3 months of wear, the patient complains of reduced vision.
Over-refraction is -0.75D OU. Subjective refraction is -0.75D greater also.
What is most likely occurring?
Case 7 - Patient has had lenses 3
months. Patient complains of discomfort immediately upon insertion. Fluorescein
evaluation with lenses off reveals a superficial staining pattern in the nasal
periphery. What might be wrong?
Case 8 - Patient complains of dry eyes
and increased lens intolerance. She received her lenses in April and it is now
November. She finds the symptoms to be worse at work. What might be the
problem?
Case 9 - Patient has had her lenses for
9 months. She admits to not always cleaning and enzyming as frequently as
directed. SLE reveals Grade 1 & 2 papilla. What should be done?
V.A.H. 2000