Clinical and pathological features of a non-crystalline form of Schnyder corneal dystrophy

Abstract

Schnyder corneal dystrophy (SCD) is a rare progressive bilateral disorder of the cornea resulting from an abnormal deposition of (un)esterified cholesterol and phospholipids throughout the cornea. SCD is an entity characterized by a varied spectrum of corneal changes, a fact that may cause difficulties for making the correct diagnosis. In previous publications, the clinical appearance has been described as a deposition of crystals predominantly located in the anterior stroma, accompanied by an arcus lipoides and a stromal haze [1]. However, Weiss et al. demonstrated that corneal crystals are found in only 54% of patients [2, 3], while the other patients presented with a disc-like central corneal opacity without subepithelial cholesterol crystals. Abnormal lipid deposition has been seen throughout the corneal stroma, but also in the basal epithelium, in the Bowman’s layer and occasionally within endothelial cells [2]. We present a patient with a non-crystalline form of SCD. We describe clinical aspects, and demonstrate light and electron microscopic features of this disease.