Search

Mutations in rhodopsin gene (RHO) are a frequent cause of retinitis pigmentosa (RP) and less often, congenital stationary night blindness (CSNB). Mutation p.G90D has previously been associated with CSNB based on the examination of one family. This study screened 60 patients. Out of these 60 patients, 32 were affected and a full characterization was conducted in 15 patients. We described the clinical characteristics of these 15 patients (12 male, median age 42 years, range 8–71) from three families including visual field (Campus Goldmann), fundus autofluorescence (FAF), optical coherence tomography (OCT) and electrophysiology. Phenotypes were classified into four categories: CSNB (N = 3, 20%) sector RP (N = 3, 20%), pericentral RP (N = 1, 6.7%) and classic RP (N = 8, 53.3% (8/15)). The phenotypes were not associated with family, sex or age (Kruskal–Wallis, p > 0.05), however, cystoid macular edema (CME) was observed only in one family. Among the subjects reporting nyctalopia, 69% (22/32) were male. The clinical characteristics of the largest p.G90D cohort so far showed a large frequency of progressive retinal degeneration with 53.3% developing RP, contrary to the previous report. [ABSTRACT FROM AUTHOR]

USH2A mutation is the most common cause of retinitis pigmentosa, with or without hearing impairment. Patients most commonly exhibit hyperautofluorescent ring on fundus autofluorescence imaging (FAF) and rod-cone dystrophy on electrophysiology. A detailed study of three USH2A patients with a rare pattern of double hyperautofluorescent rings was performed. Twenty-four patients with typical single hyperautofluorescent rings were used for comparison of the ages of onset, visual fields, optical coherence tomography, electrophysiology, and audiograms. Double rings delineated the area of pericentral retinal degeneration in all cases. Two patients exhibited rod-cone dystrophy, whereas the third had a cone-rod dystrophy type of dysfunction on electrophysiology. There was minimal progression on follow-up in all three. Patients with double rings had significantly better visual acuity, cone function, and auditory performance than the single ring group. Double rings were associated with combinations of null and missense mutations, none of the latter found in the single ring patients. According to these findings, the double hyperautofluorescent rings indicate a mild subtype of USH2A disease, characterized by pericentral retinal degeneration, mild to moderate hearing loss, and either a rod-cone or cone-rod pattern on electrophysiology, the latter expanding the known clinical spectrum of USH2A-retinopathy. [ABSTRACT FROM AUTHOR]