April 2009

Taming a Giant Recurring Corneal Erosion

History and Presentation

A 62-year-old man came to my practice on a Friday afternoon with a painful corneal abrasion that presented upon awakening. This patient had a long history of smaller recurring corneal erosions in both eyes.

Clinical Evaluation

Biomicroscopy revealed a full thickness, 6 mm x 7 mm corneal abrasion, extending to Bowman’s membrane. Because of the patient’s significant pain, I did not perform a pinhole test. His visual acuity was 20/200. I instilled 2 drops of proparacaine hydrochloride 0.5%, 20 seconds apart. Further examination revealed the epithelial tissue was loose at the margins of the abrasion. A brief attempt to irrigate the necrotic tissue at the edges of the abrasion quickly demonstrated the entire epithelium could be removed without much effort if the irrigation continued, so the irrigation was stopped.

Treatment and Follow-up

I instilled 1 drop of moxifloxacin (Vigamox, Alcon Laboratories Inc.) and applied a Biofinity contact lens (CooperVision) as a bandage (8.6/14.0/–0.50D). I prescribed moxifloxacin to be instilled every 2 hours over the bandage lens during waking hours. I instructed the patient to alternate ibuprofen and acetaminophen every 2 hours for pain management. If this pain management strategy had not been sufficient, the eye could have been cyclopleged, and a narcotic agent prescribed. The patient was instructed to return the next morning.

On day 2, the abrasion had decreased to 3 mm x 6 mm, and the patient reported only minor discomfort until I removed the bandage lens. I prefer to remove the bandage lens at each follow-up visit to allow necrotic cells and debris to clear before replacing the lens with a new one. I instilled a drop of proparacaine, which allowed me to examine the eye without the lens, and then I applied a fresh lens. I instructed the patient to decrease the 1 drop of moxifloxacin to q.i.d. and to return on Monday morning.

Outcome

The final photo shows a primarily healed abrasion on day 4 with clear borders where the epithelial plates were fusing. I removed the bandage lens and did not replace it, and I referred the patient to a local corneal specialist that afternoon for further management and possible treatment. Given this patient’s history, the likelihood of recurrence is quite high.

This case demonstrates that a combination of a low modulus, high oxygen lens, and an effective antibiotic can be used successfully manage giant corneal abrasions.

Discussion

A patient’s susceptibility to recurring corneal abrasions can be intrinsic (corneal dystrophy) or acquired through trauma, in which cells are lost and new cells do not reattach to Bowman’s membrane as strongly as before. An analogy would be a golf divot in the grass. When someone replaces the divot, it may look fine, but it’s not as tightly rooted as the area around it.

Another mechanism is related to a degeneration of the whole sheet of epithelial basement cells and their attachment to Bowman’s membrane. This condition often is found in patients who have epithelial basement membrane defects. Studies have found a defect in collagen fibrils that anchor the corneal epithelium to the basement membrane to Bowman's layer.

This patient had the degenerative form in which the epithelium is poorly attached. He will likely have many more episodes of erosions, unless the corneal specialist is successful in scarring the epithelium down with micropuncture or laser treatment.

By Donald J. Siegel, OD
Sun City West, Ariz.

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