FUNDUS ALBILINEATUS EVANESCENS : A NEW RECESSIVE RETINAL DYSTROPHY?

Abstract

Abstract: : Purpose: To describe the phenotype and follow–up of a new recessive retinal dystrophy. Methods:The probant from a consanguineous Turkish family was clinically investigated at 5 months of age and followed for the next 8 years. Complete eye examination was regularly performed, including fluorescein angiography, full–field electroretinography (ERG) and ocular coherence tomography (OCT). Twenty six family members were also examined for similar changes and blood was drawn. Results:At five months of age, refraction revealed a severe hyperopia of +10 diopters OU with axial length of 16.5mm OD and 17.3mm OS. Fundus examination showed a dystrophic maculo–papillar bundle and a vascularized fovea. Multiple whitish deep intraretinal linear lesions were present in the mid–periphery, with no preferential orientation, and sparing the macula. These lesions were angiographically hypofluorescent. ERG performed elsewhere was interpreted as normal. By 8 years of age, visual acuity was 20/25 OD and 20/30 OS with S+14 OU without nystagmus nor strabismus. Goldmann visual field was normal. The whitish linear deposits had disappeared and were replaced by small areas of slight retinal pigment epithelium alterations. Full field ERG revealed normal amplitudes but mildly delayed culmination time of both scotopic and photopic b wave. OCT revealed a thickened macula for age, measuring 398 microns. The presence of this phenotype was excluded in all examined family members. Conclusions:This phenotype which consists of evanescent white linear intraretinal deposits, mildly dystrophic macula and hyperopia represents a new disorder and appears to follow a recessive mode of inheritance. This condition is a mild and non progressive amblyogenic disease. The structure of the pedigree is amenable to homozygosity mapping.

Keywords: retinal degenerations: hereditary • gene/expression • genetics