Extending The Phenotypical description Of Patients With Early Onset Severe Retinal Degeneration (EOSRD) Caused By RPE65–Mutations

Abstract

Abstract: : Purpose: To describe the ocular phenotype of patients with autosomal recessive early onset severe retinal degeneration (EOSRD) associated with RPE65 mutations longitudinally and crossectionally. Methods: Six children (4 families) and 3 adult siblings with RPE65 mutations on both alleles. Clinical examination, psychophysics (colour vision, kinetic visual fields), fullfield ERG, optical coherence tomography (OCT) and fundus autofluorescence (AF). Results: Visual acuity and visual fields were measurable in all young patients (aged 5 to 14 y, fields not tested in the 5 y old), but only in 1/3 of the older patients (aged 43 to 54 y). Fine nystagmus was present in 4/6 of the young and 2/3 of the older patients. Photophobia was absent in all young and present in all elder patients. Funduscopic changes were discrete during the first decade of life in 5/6, one patient had clear macular changes already at age 5. All 3 elder siblings had macular changes, peripapillary hypopigmentation and severely constricted vessels, but no bone spicules. Some colour vision was present in all patients with measurable visual acuity. Rod ERGs were absent at any age, cone ERGs were detectable in three children under 1 year. OCT performed in 5/6 children and in one adult was indicative of viable photoreceptors in all young patients. Fundus autofluorescence (AF) was absent at any age (Lorenz et al., Ophthalmology, in press). Conclusions: Visual function in childhood was better than typically seen in Leber Congenital Amaurosis (LCA), hence the classification as EOSRD appears more appropriate. The progressive retinal changes appear to have a relatively characteristic pattern with limited inter– and intrafamilial variation. The most prominent feature is the absence of AF from childhood on. OCT would indicate viable photoreceptors at least during the first 15 years of life.

Keywords: retinal degenerations: hereditary • photoreceptors • retinal pigment epithelium