What is recurrent corneal erosion (RCE)?
The cornea is the clear, dome-shaped covering of the eye. RCE occurs when the outer layer of the cornea, known as the epithelium, loosens or peels off. Normally the epithelium is tightly adhered to the layer of the cornea beneath it.
Since the cornea is very sensitive, RCE causes a lot of pain for the eye. Additionally, the pain is worse when you wake up. When the eyelids are closed during sleep, the reduced oxygen supply causes mild swelling of the epithelium. This swelling can cause the epithelium to stick to the under surface of the eyelid. Upon awakening, this loose tissue peels off when opening the eyes, resulting in moderate to severe pain.
The pain may last for a couple of hours or up to several days. In fact it could happened several times a year. These events usually resolve quickly, so RCE symptoms are often ignored. An optometrist should be consulted to properly diagnose and treat RCE to minimize the discomfort experienced and provide solutions to prevent future recurrences.
What causes RCE?
Most cases of RCE are associated with prior corneal trauma, such as a previous scratch. Other cases are associated with an underlying corneal dystrophy (where the cornea deteriorates over time). As mentioned earlier, the epithelium is normally tightly adhered to the underlying layer. Sometimes after an injury there are insufficient or defective connections to anchor the epithelium to the rest of the cornea, leaving the epithelium susceptible to peeling.
Patients who have an underlying corneal dystrophy naturally have loose epithelium. This is usually present at birth but does not manifest itself until early adulthood. It is important to note that patients rarely experience permanent vision loss from RCE.
How do you treat RCE?
There are many treatments for RCE, and each case should be assessed individually. The simplest therapy involves non-preserved artificial tears used frequently throughout the day and ointments applied before bed.
During an acute attack, antibiotics, anti-inflammatory eye drops and pain relievers may be required. For large erosions, an oxygen-penetrable bandage contact lens may also be used. Due to the recurrent nature of this condition, drops may need to be used for long periods of time.
In extreme cases, surgical intervention by an ophthalmologist may be required. Where corneal trauma has occurred, it is important to have the eye treated properly by an optometrist to reduce the chance of experiencing RCE at a later date.