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where <strong>the</strong>re is extensive disadhesion of <strong>the</strong><br />

epi<strong>the</strong>lium, mechanical debridement of <strong>the</strong><br />

loose epi<strong>the</strong>lium is required. Debridement<br />

provides for a smoo<strong>the</strong>r epi<strong>the</strong>lial basement<br />

membrane which can <strong>the</strong>n be resurfaced with<br />

a healthy epi<strong>the</strong>lium. Debridement of loose<br />

epi<strong>the</strong>lium assists healing and resolves pain<br />

sooner, but does nothing to prevent<br />

recurrences. This is not that surprising, as<br />

with RCE syndrome <strong>the</strong> problem is more one<br />

of epi<strong>the</strong>lial adherence ra<strong>the</strong>r than epi<strong>the</strong>lial<br />

resurfacing 3 . Pressure patching will always be<br />

required following debridement and it is<br />

often suggested that <strong>the</strong> patient should be<br />

patched bilaterally to completely immobilise<br />

<strong>the</strong> eyes 2 . Patching should only be done for<br />

up to 72 hours and if <strong>the</strong> corneal abrasion<br />

has not resolved within this time, <strong>the</strong>n <strong>the</strong><br />

use of a <strong>the</strong>rapeutic (bandage) soft contact<br />

lens should be considered.<br />

Prophylactic treatment of RCE syndrome is<br />

aimed more at preventing recurrences of <strong>the</strong><br />

corneal erosions. Fluid accumulating beneath<br />

<strong>the</strong> epi<strong>the</strong>lium during <strong>the</strong> night – caused by<br />

<strong>the</strong> tears becoming hypotonic during sleep –<br />

leading to disadhesion of <strong>the</strong> epi<strong>the</strong>lium,<br />

and adherence of <strong>the</strong> epi<strong>the</strong>lium to <strong>the</strong><br />

tarsal conjunctiva, are thought to be <strong>the</strong> two<br />

major factors leading to recurrence.<br />

A lubricating ointment – such as<br />

Lacrilube® (Allergan) – can be used as a<br />

prophylactic treatment in <strong>the</strong> management of<br />

RCE syndrome, through application at<br />

bedtime to prevent adhesion between <strong>the</strong><br />

corneal epi<strong>the</strong>lium and <strong>the</strong> eyelid during<br />

sleep 3 . However, using just a lubricating<br />

agent as a prophylactic treatment for RCE<br />

syndrome may not always be successful, as<br />

this does little to prevent <strong>the</strong> fluid intake by<br />

<strong>the</strong> cornea during <strong>the</strong> night, which is<br />

generally believed to cause <strong>the</strong> disadhesion<br />

of <strong>the</strong> epi<strong>the</strong>lium 3,5 . In view of this, an<br />

alternative approach to prophylaxis is to use<br />

an ophthalmic ointment, such as Muro 128®<br />

(Bausch & Lomb), which also incorporates a<br />

hypertonic agent to promote corneal<br />

desiccation.<br />

Ano<strong>the</strong>r form of prophylaxis for RCE<br />

syndrome is to use a bandage contact lens.<br />

This form of treatment will generally be<br />

adopted when application of <strong>the</strong> hypertonic<br />

ointment (or drops) has been unsuccessful in<br />

preventing recurrences. A thin medium to<br />

high-water content, loosely fitting<br />

<strong>the</strong>rapeutic soft contact lens worn on a<br />

continuous (extended wear) basis for at least<br />

two months will protect <strong>the</strong> epi<strong>the</strong>lium while<br />

it reattaches itself to <strong>the</strong> basement<br />

membrane. The new silicone hydrogel contact<br />

lenses – with <strong>the</strong>ir greatly increased oxygen<br />

transmissibility – are also a good option in<br />

this regard, as <strong>the</strong>y have <strong>the</strong> potential to<br />

promote faster corneal healing through <strong>the</strong><br />

delivery of higher levels of oxygen to <strong>the</strong><br />

cornea during extended wear.<br />

The wearing of a <strong>the</strong>rapeutic contact lens<br />

may precipitate corneal erosions in some<br />

patients. The o<strong>the</strong>r major problem with this<br />

form of treatment relates to <strong>the</strong> risks<br />

associated with <strong>the</strong> extended wear of a soft<br />

contact lens 7 , especially when that lens is<br />

worn continuously for 60 days or more. In<br />

particular, <strong>the</strong> risk of corneal infection is<br />

greatly increased by <strong>the</strong> wearing of a soft<br />

contact lens on a continuous basis 8 , so<br />

consideration should be given to using a<br />

prophylactic antibiotic medication in<br />

combination with <strong>the</strong> contact lens for <strong>the</strong><br />

duration of <strong>the</strong> extended wear.<br />

The nightly administration of an<br />

ophthalmic ointment or eyedrop (preferably<br />

<strong>the</strong> former), which incorporates both a<br />

lubricating agent (to prevent adhesion<br />

between <strong>the</strong> corneal epi<strong>the</strong>lium and <strong>the</strong><br />

eyelid) and a hypertonic agent (to produce<br />

corneal desiccation), is certainly a more<br />

conservative treatment option with less<br />

associated risk compared to a bandage<br />

contact lens used on an extended wear basis.<br />

To be successful, patients should be advised<br />

that application of <strong>the</strong> ointment may need<br />

to be continued for a period of between 4 to<br />

12 weeks.<br />

In severe cases, where nei<strong>the</strong>r a bandage<br />

contact lens or a hypertonic agent is<br />

successful in preventing frequent recurrences,<br />

<strong>the</strong>re are a number of o<strong>the</strong>r treatment<br />

options. Anterior stromal puncture is very<br />

effective in managing post-traumatic<br />

macroerosions. Multiple micropunctures made<br />

in <strong>the</strong> anterior stroma incite focal scarring<br />

leading to more secure epi<strong>the</strong>lial adhesion.<br />

Alternatively, superficial epi<strong>the</strong>lial<br />

keratectomy involves debriding <strong>the</strong><br />

epi<strong>the</strong>lium, usually just in <strong>the</strong> affected area,<br />

also with subsequent scarification. The<br />

resultant scarring with <strong>the</strong>se procedures<br />

means that treatment near or on <strong>the</strong> visual<br />

axis should be avoided if possible 1,3 .<br />

Photo<strong>the</strong>rapeutic keratectomy (PTK) is<br />

often effective when ano<strong>the</strong>r treatment has<br />

failed. PTK can be used in resistant cases of<br />

recurrent erosions to smooth <strong>the</strong><br />

subepi<strong>the</strong>lial corneal surface, creating a<br />

substrate more conducive to epi<strong>the</strong>lial<br />

migration and adhesion 9 . The treatment<br />

involves mechanical debridement of <strong>the</strong><br />

epi<strong>the</strong>lium followed by a plano ablation of<br />

usually less than 10 microns. This may be<br />

combined with a refractive ablation in<br />

suitable ametropic patients. The ablation<br />

zone diameter is generally determined by <strong>the</strong><br />

Figure 2:<br />

Computerised videokeratography<br />

showing a typical topographic<br />

lagoon – a small focal (blue) area of<br />

corneal flattening just slightly<br />

superotemporal to <strong>the</strong> corneal vertex –<br />

in a patient with RCE syndrome<br />

extent of changes to <strong>the</strong> epi<strong>the</strong>lial basement<br />

membrane.<br />

The prognosis for a patient with RCE<br />

syndrome is generally quite good. The<br />

condition will usually heal if <strong>the</strong> underlying<br />

cause is properly diagnosed and remediated<br />

(if this is possible). If <strong>the</strong> condition is<br />

chronic, <strong>the</strong> patient must be instructed on<br />

appropriate prophylactic measures and<br />

advised of <strong>the</strong> need for indefinite<br />

continuation of procedures. Most<br />

importantly, patients should be reassured<br />

that most cases of RCE heal eventually or are<br />

controllable without visual loss.<br />

About <strong>the</strong> author<br />

Richard G. Lindsay is a Senior Fellow at <strong>the</strong><br />

Department of Optometry and Vision<br />

Sciences, University of Melbourne, Victoria,<br />

Australia, and an optometrist in private<br />

practice in East Melbourne.<br />

References<br />

1. Kanski, J. (1994) ‘Clinical<br />

Ophthalmology’. 3rd ed. Butterworths,<br />

London, 135-136.<br />

2. Catania, L. (1995) ‘Primary Care of <strong>the</strong><br />

Anterior Segment’. 2nd ed. Appleton &<br />

Lange, Conneticut, 237-241.<br />

3. Brown, N. and Bron, A. (1976)<br />

“Recurrent erosion of <strong>the</strong> cornea”. Brit.<br />

J. Ophthal. 60: 84-96.<br />

4. Waring, G.O., Rodrigues, M.M. and<br />

Laibson, P.R. (1978) “Corneal<br />

dystrophies. 1. Dystrophies of <strong>the</strong><br />

epi<strong>the</strong>lium, Bowman’s layer and stroma”.<br />

Surv. Ophthalmol. 23: 71-122.<br />

5. Chandler, P.A. (1945) “Recurrent erosion<br />

of <strong>the</strong> cornea”. Am. J. Ophthalmol.<br />

28: 355-367.<br />

6. McGhee, C.N.J., Bryce, I.G., Anastas, C.N.,<br />

Webber, S.K., Burvill, M. and Murray, A.T.<br />

(1996) “Corneal topographic lagoons: a<br />

potential new marker for post-traumatic<br />

recurrent corneal erosion syndrome”. Aust.<br />

NZ J. Ophthal. 24: 27-31.<br />

7. Bruce, A.S. and Brennan, N.A. (1990)<br />

“Corneal pathophysiology with contact<br />

lens wear”. Surv. Ophthalmol. 35: 25-58.<br />

8. Brennan, N.A. and Coles, M.L.C. (1997)<br />

“Extended wear in perspective”. Optom.<br />

Vis. Sci. 74: 609-623.<br />

9. Harkins, T. (1995) “The excimer laser and<br />

photo<strong>the</strong>rapeutic keratectomy”.<br />

Clin. Eye Vis. Care 7: 103-106.<br />

www.optometry.co.uk 43

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