Best's disease

Abstract

Best's disease is an inherited macular dystrophy with autosomal dominant inheritance pattern, characterized by the presence of autofluorescent vitelliform deposition whose development is stereotyped from its manifestation to the fragmentation of the material and then to its resorption. Age at onset is between 7 and 12 years. Except in the presence of complications, patients are more often asymptomatic and the disease is discovered fortuitously. We report the case of 8 year-old only daughter with no particular past medical history. Ophthalmologic examination showed corrected visual acuity 7/10 in the left and right eyes, the examination of the anterior segment was normal, fundus examination showed macular yellowish-white stain (A, B). On fluorescein angiography, hyperfluorescence occurred early followed by a hypofluorescence. Macular imaging by optical coherence tomography (OCT) showed the presence of an empty optical space between the neuroretina and the pigment epithelium (C, D). Assessment was performed: electrooculogram was perturbed using Arden ratio of 146% in the right eye and 179% in the left eye. Electroretinogram, visual fields and color vision test were normal. Fundus examination of parents was normal. The diagnosis of previtelliform BEST's disease was made based on early hypofluorescence, OCT appearance and alteration of the electroretinogram. Differential diagnoses included: stargardt's disease, progressive dystrophy of the cones and X-linked retinoschisis. No treatment was proposed, only simple monitoring.