VISUAL IMPAIRMENT IN RETINITIS PIGMENTOSA.

PURPOSE: Retinitis pigmentosa (RP) is an inherited pigmentary retinal dystrophy where patients experience poor peripheral, night, and eventually central vision. There are statements in the literature which suggest visual acuity loss can progress to total blindness in these patients. This study sought to examine these statements by performing a retrospective analysis of the visual acuity measured in a large cohort of RP patients. METHODS: The charts of 1,095 RP patients were reviewed in this retrospective cross-sectional analysis. They included all of the RP patients examined by one of the authors (G.A.F.). Patients with sector RP or a delimited form of this disease were not included. The review was focused on the analysis of patients with 20/200 or worse vision in the better-seeing eye (N = 215). RESULTS: We determined that 0.46% of the enrolled patients progressed to no light perception in each eye. Ninety-two percent of the 1,095 patients examined were able to read a visual acuity chart. There were 6.8% who saw only hand motion, count fingers, or light perception. CONCLUSION: No light perception was measured in only 0.46% of patients. Thus, only a very small number of the RP patients in our cohort progressed to total blindness.