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Richard G. Lindsay BScOptom, MBA, FAAO DipCL
Recurrent corneal erosion syndrome
Recurrent corneal erosion (RCE) syndrome is a condition which is characterised by a
disturbance at the level of the corneal epithelial basement membrane resulting in
defective adhesion and recurrent breakdown of the epithelium 1 .
RCE syndrome may occur secondary to
corneal injury or else spontaneously 2 . In the
latter case, there is often some predisposing
factor, such as diabetes or a corneal
dystrophy 1-3 . Management of the problem is
usually aimed at regenerating or repairing
the epithelial basement membrane so as to
restore the adhesions between the
epithelium and the anterior stroma.
Aetiology
The corneal epithelial basement membrane
complex is responsible for the tight adhesion
of the epithelial basal cell layer to the
underlying stroma. The primary abnormality
with RCE syndrome is poor adhesion of the
epithelium to Bowman’s layer due to a
failure to establish or maintain normal
adhesion complexes. Multiple recurrences are
common, because the basal epithelial cells
require at least 8 to 12 weeks to regenerate
or repair the epithelial basement membrane 2 .
The most common cause of RCE syndrome
is trauma to the cornea. In these cases,
patients will generally give a history of
previous oblique corneal abrasion with an
object such as a fingernail, piece of paper or
twig 4 . The original injury is generally well
recalled by the patient as it is usually
followed by several days of pain, watering
and photophobia. The first recurrence may
then not occur for quite a few months after
the original trauma. Epithelial injuries where
the basement membrane is preserved are
unlikely to be followed by recurrent corneal
erosions.
RCE syndrome can also occur
spontaneously, although in this situation
there is often some predisposing factor. For
example, many corneal dystrophies are
associated with recurrent corneal erosions.
Epithelial basement membrane dystrophy
(EBMD, also known as Cogan’s microcystic
dystrophy or map-dot-fingerprint dystrophy)
is commonly associated with RCE syndrome,
with about half the patients with recurrent
epithelial erosions exhibiting EBMD 3 . Other
corneal dystrophies which can lead to
recurrent erosions include Reis-Bücklers’
dystrophy (a dystrophy occurring at the
level of Bowman’s layer, also known as
ring-shaped dystrophy), stromal dystrophies
such as granular and lattice, and Fuchs’
endothelial dystrophy 4 .
Spontaneous recurrent erosions, with an
autosomal dominant inheritance pattern,
have been described in 40 members of one
family 3 . RCE syndrome also appears to be
more common in patients with diabetes
mellitus (due to basement membrane
thickening and abnormal adhesion
complexes) as well as in post-operative
patients who have undergone ocular surgical
procedures such as cataract extraction (with
intraocular lens implantation) or refractive
surgery 2 .
Consequently, for patients who present
with signs and symptoms of RCE syndrome, a
careful history and examination of the
corneae should be undertaken to ensure
there are no underlying factors which may
have predisposed the patient to this
condition. This applies even in cases where
there is a history of injury to the cornea – a
defect in the epithelial basement membrane
complex may have been present before the
initial trauma 3 .
Presentation
Patients will usually present with a history of
pain (nearly always unilateral) on waking,
associated with lacrimation, photophobia
and blurred vision. External eye examination
will generally show a corneal abrasion, often
centrally located, which stains brightly with
fluorescein (Figure 1). The abraded area
tends to create loose edges with moderate to
large epithelial flaps commonly forming. A
brownish granular oedema (brawny oedema)
may occupy the underlying anterior stroma.
The tendency towards central location and
dense secondary oedema can cause vision to
be significantly affected 2 .
Recurrent corneal erosions can be classed
as either macroform or microform 5 . With the
former, there will be severe pain persisting
for hours to days as a result of a large area
of epithelium being separated from the
cornea (as in Figure 1). In post-traumatic
cases, the macroerosion will always occur at
Figure 1: Recurrent (macroform) corneal erosion
the site of the original abrasion. Microform
recurrent erosions are characterised by
intraepithelial microcysts with a minor break
in the epithelium. These will usually be
associated with very brief episodes of pain,
lasting seconds or minutes.
Corneal topographic analysis (using
computerised videokeratography) often
reveals focal areas of corneal flattening
(called “corneal topographic lagoons”) in
eyes with RCE syndrome 6 . This is an
important finding, as the identification of
areas of focal abnormality in RCE syndrome
remains a significant clinical problem in
those patients with frank symptoms but no
evident epithelial abnormalities. Figure 2
shows such a corneal topographic lagoon in
a patient with a history of RCE syndrome.
Management
Management of RCE syndrome is usually
aimed at regenerating or repairing the
epithelial basement membrane so as to
restore the adhesions between the
epithelium and the anterior stroma. In mild
cases, the condition may resolve
spontaneously within a few hours. More
often, however, treatment is required to
promote healing and relieve the patient’s
symptoms. It should also be noted that the
healing rate for an abrasion occurring as a
part of RCE syndrome is generally slower than
the normal rate for a similar abrasion caused
by other factors.
There are two options for treatment
during the acute stage of recurrent erosion.
The first one is just to apply a pressure patch
to the affected eye for 24 hours, combined
with a mild cycloplegic and a prophylactic
antibiotic ointment. For more severe cases,
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April 6, 2001 OT
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where there is extensive disadhesion of the
epithelium, mechanical debridement of the
loose epithelium is required. Debridement
provides for a smoother epithelial basement
membrane which can then be resurfaced with
a healthy epithelium. Debridement of loose
epithelium assists healing and resolves pain
sooner, but does nothing to prevent
recurrences. This is not that surprising, as
with RCE syndrome the problem is more one
of epithelial adherence rather than epithelial
resurfacing 3 . Pressure patching will always be
required following debridement and it is
often suggested that the patient should be
patched bilaterally to completely immobilise
the eyes 2 . Patching should only be done for
up to 72 hours and if the corneal abrasion
has not resolved within this time, then the
use of a therapeutic (bandage) soft contact
lens should be considered.
Prophylactic treatment of RCE syndrome is
aimed more at preventing recurrences of the
corneal erosions. Fluid accumulating beneath
the epithelium during the night – caused by
the tears becoming hypotonic during sleep –
leading to disadhesion of the epithelium,
and adherence of the epithelium to the
tarsal conjunctiva, are thought to be the two
major factors leading to recurrence.
A lubricating ointment – such as
Lacrilube® (Allergan) – can be used as a
prophylactic treatment in the management of
RCE syndrome, through application at
bedtime to prevent adhesion between the
corneal epithelium and the eyelid during
sleep 3 . However, using just a lubricating
agent as a prophylactic treatment for RCE
syndrome may not always be successful, as
this does little to prevent the fluid intake by
the cornea during the night, which is
generally believed to cause the disadhesion
of the epithelium 3,5 . In view of this, an
alternative approach to prophylaxis is to use
an ophthalmic ointment, such as Muro 128®
(Bausch & Lomb), which also incorporates a
hypertonic agent to promote corneal
desiccation.
Another form of prophylaxis for RCE
syndrome is to use a bandage contact lens.
This form of treatment will generally be
adopted when application of the hypertonic
ointment (or drops) has been unsuccessful in
preventing recurrences. A thin medium to
high-water content, loosely fitting
therapeutic soft contact lens worn on a
continuous (extended wear) basis for at least
two months will protect the epithelium while
it reattaches itself to the basement
membrane. The new silicone hydrogel contact
lenses – with their greatly increased oxygen
transmissibility – are also a good option in
this regard, as they have the potential to
promote faster corneal healing through the
delivery of higher levels of oxygen to the
cornea during extended wear.
The wearing of a therapeutic contact lens
may precipitate corneal erosions in some
patients. The other major problem with this
form of treatment relates to the risks
associated with the extended wear of a soft
contact lens 7 , especially when that lens is
worn continuously for 60 days or more. In
particular, the risk of corneal infection is
greatly increased by the wearing of a soft
contact lens on a continuous basis 8 , so
consideration should be given to using a
prophylactic antibiotic medication in
combination with the contact lens for the
duration of the extended wear.
The nightly administration of an
ophthalmic ointment or eyedrop (preferably
the former), which incorporates both a
lubricating agent (to prevent adhesion
between the corneal epithelium and the
eyelid) and a hypertonic agent (to produce
corneal desiccation), is certainly a more
conservative treatment option with less
associated risk compared to a bandage
contact lens used on an extended wear basis.
To be successful, patients should be advised
that application of the ointment may need
to be continued for a period of between 4 to
12 weeks.
In severe cases, where neither a bandage
contact lens or a hypertonic agent is
successful in preventing frequent recurrences,
there are a number of other treatment
options. Anterior stromal puncture is very
effective in managing post-traumatic
macroerosions. Multiple micropunctures made
in the anterior stroma incite focal scarring
leading to more secure epithelial adhesion.
Alternatively, superficial epithelial
keratectomy involves debriding the
epithelium, usually just in the affected area,
also with subsequent scarification. The
resultant scarring with these procedures
means that treatment near or on the visual
axis should be avoided if possible 1,3 .
Phototherapeutic keratectomy (PTK) is
often effective when another treatment has
failed. PTK can be used in resistant cases of
recurrent erosions to smooth the
subepithelial corneal surface, creating a
substrate more conducive to epithelial
migration and adhesion 9 . The treatment
involves mechanical debridement of the
epithelium followed by a plano ablation of
usually less than 10 microns. This may be
combined with a refractive ablation in
suitable ametropic patients. The ablation
zone diameter is generally determined by the
Figure 2:
Computerised videokeratography
showing a typical topographic
lagoon – a small focal (blue) area of
corneal flattening just slightly
superotemporal to the corneal vertex –
in a patient with RCE syndrome
extent of changes to the epithelial basement
membrane.
The prognosis for a patient with RCE
syndrome is generally quite good. The
condition will usually heal if the underlying
cause is properly diagnosed and remediated
(if this is possible). If the condition is
chronic, the patient must be instructed on
appropriate prophylactic measures and
advised of the need for indefinite
continuation of procedures. Most
importantly, patients should be reassured
that most cases of RCE heal eventually or are
controllable without visual loss.
About the author
Richard G. Lindsay is a Senior Fellow at the
Department of Optometry and Vision
Sciences, University of Melbourne, Victoria,
Australia, and an optometrist in private
practice in East Melbourne.
References
1. Kanski, J. (1994) ‘Clinical
Ophthalmology’. 3rd ed. Butterworths,
London, 135-136.
2. Catania, L. (1995) ‘Primary Care of the
Anterior Segment’. 2nd ed. Appleton &
Lange, Conneticut, 237-241.
3. Brown, N. and Bron, A. (1976)
“Recurrent erosion of the cornea”. Brit.
J. Ophthal. 60: 84-96.
4. Waring, G.O., Rodrigues, M.M. and
Laibson, P.R. (1978) “Corneal
dystrophies. 1. Dystrophies of the
epithelium, Bowman’s layer and stroma”.
Surv. Ophthalmol. 23: 71-122.
5. Chandler, P.A. (1945) “Recurrent erosion
of the cornea”. Am. J. Ophthalmol.
28: 355-367.
6. McGhee, C.N.J., Bryce, I.G., Anastas, C.N.,
Webber, S.K., Burvill, M. and Murray, A.T.
(1996) “Corneal topographic lagoons: a
potential new marker for post-traumatic
recurrent corneal erosion syndrome”. Aust.
NZ J. Ophthal. 24: 27-31.
7. Bruce, A.S. and Brennan, N.A. (1990)
“Corneal pathophysiology with contact
lens wear”. Surv. Ophthalmol. 35: 25-58.
8. Brennan, N.A. and Coles, M.L.C. (1997)
“Extended wear in perspective”. Optom.
Vis. Sci. 74: 609-623.
9. Harkins, T. (1995) “The excimer laser and
phototherapeutic keratectomy”.
Clin. Eye Vis. Care 7: 103-106.
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