A new, band-shaped and whorled microcystic dystrophy of the corneal epithelium.

Five family members and three unrelated patients (four women, four men, 23 to 71 years old) had a dystrophy of the corneal epithelium. Direct slit-lamp examination showed bilateral or unilateral, gray, band-shaped, and feathery opacities that sometimes appeared in whorled patterns. Retroillumination showed intraepithelial, densely crowded, clear microcysts. Light and electron microscopy disclosed diffuse vacuolization of the cytoplasm of epithelial cells in the affected area. Visual acuity was so reduced in three patients that abrasion of the corneal epithelium was performed. The corneal abnormalities recurred within months, with the same reduction in visual acuity as before. The corneal opacities were progressive in two patients but diminished noticeably in another after he began using a hard contact lens. We found no other ophthalmic irregularities or associated systemic abnormalities and no indication of drug-induced keratopathy.

[Current status of linkage studies for gene localization in corneal dystrophies]. / Derzeitiger Stand der Koppelungsuntersuchungen zur Genlokalisation von Hornhautdystrophien.

Corneal dystrophies with primarily autosomal dominant inheritance have been clearly identified both histologically and histochemically. No information is available to date on the causal enzymatic protein defect of the individual forms of dystrophy. By using linkage analysis to study families with various corneal dystrophies, an attempt is being made with polymorphous markers to find an indirect indication for localization in a chromosome. Numerous factors which exclude linkage can be named for granular, lattice and Schnyder's corneal dystrophy. Our linkage analysis studies of a second family with Schnyder's dystrophy support our indications of linkage with the sites for adenylate kinase (AK1) and the AB0 blood groups on chromosome 9.