Recurrent corneal erosion syndrome (RCE) is a condition in which a superficial abrasion of the cornea fails to heal properly. The outermost layer of the cornea – the epithelium – repeatedly breaks down, giving the sufferer recurrent symptoms of sharp pain, watering, a foreign-body sensation, and redness, often many months after the initial injury.
What causes it?
The majority of cases of RCE are caused by trauma, often trivial, and sometimes the patient may not even remember the injury. The corneal epithelium generally heals quickly; but in RCE it fails to ‘bed down’ properly and attach to the underlying layer of the cornea – the basement membrane. This leaves the epithelium loose, slightly mobile, and vulnerable to further damage.
A smaller, but significant, proportion occur in people who have an abnormal basement membrane; in conditions such as ‘Map-dot-fingerprint dystrophy’.
The recurrent episode typically occurs when the eye dries out, especially overnight: patients often give a story of waking in the morning, opening their eyes, and immediately experiencing a sharp pain in the affected eye. This may resolve after a few hours, or may persist for a day or two.
How is it treated?
Treatment may be medical or surgical. The simplest option is lubricants, especially at night, to keep the eye moist and ensure the lids glide smoothly over the cornea rather than rubbing on it.
A thick ointment such as Lacrilube is ideal as it can be instilled at bedtime, and will last overnight. This can be augmented with lighter-weight lubricant gels or drops during the daytime.
For large areas of epithelial breakdown, a bandage contact lens (a zero-power therapeutic lens, placed on the eye by the doctor) may be used to make the eye more comfortable. This lens is usually worn continuously for up to six months, changed every four weeks; this may improve healing rate, but there is a significant risk of corneal infection, and any patient developing redness or pain in an eye with such a lens should seek ophthalmic attention urgently.
90% of cases of RCE do resolve eventually, but often require the diligent use of lubricants for 6 months or more.
What does the surgery involve?
If recurrent episodes still occur despite medical treatment, surgery may be the next step.
Under local anaesthetic, the existing corneal epithelium is removed with alcohol, and then the basement membrane layer is smoothed. A bandage contact lens is placed on the eye, and over the next few days fresh epithelium grows across the cornea.
How long will the recovery take?
Superficial keratectomy heals rapidly, and the bandage contact lens helps to keep the eye comfortable. Antibiotic eye drops reduce the risk of post-operative infection. Some grittiness and redness is normal for the first few days, but after a week the eye has usually healed.
What complications can occur?
As with any surgical procedure there is a small risk of infection. If the RCE is due to simple trauma in the context of a healthy basement membrane, this procedure usually gives good results. If the RCE is associated with basement membrane abnormalities, such as map-dot-fingerprint dystrophy, healing may take longer.
Rarely, the procedure may result in a shift in the refraction of the eye, resulting in a change in the glasses prescription. This usually settles with time.
If the eye becomes more painful, more red, or the vision deteriorates after surgery, it is very important to seek ophthalmic attention.