Causes: epithelial cell loss during storage, surface trauma intra-operatively, eye rubbing, lid malposition or medication toxicity.
Normally, the defect will re-epithelialize by the dividing and migrating host epithelium from the limbus within a week.
Clinical Features
Minimal to significant loss of corneal epithelial cells can be easily seen after fluorescein staining and using the cobalt blue filter.
Delayed epithelialization may occur in graft with an extensive epithelial defect and eyes with compromised healing ability i.e. post-chemical or radiation injury, Stevens-Johnson syndrome, ocular pemphigoid, rosacea keratitis, or chronic blepharitis with meibomian gland dysfunction.
Nonhealing epithelial defect may be complicated by corneal melting, thinning, perforation, infection or graft rejection.
Management
Routine follow-up with fluorescein to evaluate the corneal after corneal transplantation surgery is important because epithelial integrity is vital for graft survival.
Treatment of pre-existing eye conditions pre-operatively i.e. punctal occlusion in eyes with pre-existing dry-eyes.
Meticulous protection and handling of the corneal button epithelium during surgery to minimize epithelial loss / damage.
Bandage soft contact lens or a lateral tarsoraphy may be helpful in eyes with chronic non-healing defects.