Subepithelial Corneal Degenerations

Synonyms

Peripheral hypertrophic subepithelial corneal degeneration

Definition

Peripheral hypertrophic subepithelial corneal degeneration (PHSCD) is an idiopathic disorder that consists of peripheral, bilateral, elevated subepithelial corneal opacities, and adjacent abnormal limbal vasculature.

Etiology

The cause of PHSCD is unknown, though the lack of coexisting systemic or local ocular disease suggests that it is a primary condition. Similarities to familial pterygoid corneal dystrophy suggest that PHSCD may have a genetic component.

Clinical Presentation

PHSCD presents with peripheral, usually bilateral, symmetric elevated circumferential peripheral subepithelial corneal opacities (often sausage-roll shaped) and adjacent abnormal limbal vasculature. In most cases, the opacifications deform the normal shape of the cornea, leading to pronounced astigmatism. Some present with pseudopterygia. There is no chronic ocular surface inflammation. Symptoms include ocular surface discomfort...