Purpose
Retinal dystrophies are commonly characterized by abnormalities in lipofuscin metabolism and accumulation. Although many are considered macular diseases, they are in fact panretinal diseases and may have FAF abnormalities throughout the retinal periphery. Ultra-widefield fundus autofluoresence (FAF) is an emerging technology that allows for the characterization of the peripheral retinal features of vitreoretinal diseases. In this study, we describe the FAF patterns of several retinal dystrophies and their genotypic/phenotypic associations.
Methods
An IRB-approved retrospective consecutive case series was performed of retinal dystrophy patients who underwent ultra-widefield FAF imaging. Patients were imaged with the Optos 200Tx system. Spectral domain OCT was used to measure macular thickness. Visual acuity was measured using a standard Snellen chart. Clinical variables, genotypes, and phenotypic characteristics were reviewed.
Results
Thirty-two patients were identified. The diseases included in this study were Retinitis Pigmentosa (n = 11), Stargardt disease (n = 7), Leber Congenital Amaurosis (n = 4), Rod-Cone Dystrophy (n = 3), Congenital Stationary Night Blindness (n = 2), Pattern Dystrophy (n = 2), North Carolina Macular dystrophy (n = 1), Doyne honeycomb macular dystrophy (n = 1), and Goldman-Favre enhanced S cone syndrome (n = 1). Macular FAF abnormalities were noted in 100% of cases. 48% of cases had peripheral FAF abnormalities. All patients with Retinitis Pigmentosa 100% demonstrated peripheral FAF abnormalities with focal areas of hyper- and hypofluorescence. Patients with vision worse than 20/60 had an average central subfield thickness (CST) of 170 um whereas patients with vision better than 20/60 had CST of 245 um. (p<0.001)
Conclusions
Distinctive macular and peripheral FAF patterns are identified in a large percentage of patients with retinal dystrophies. The functional and prognostic significance of these abnormalities is not completely understood and deserves further research. Ultra-widefield imaging may provide important information to facilitate diagnosis and follow-up of these challenging cases.
Keywords: 696 retinal degenerations: hereditary •
688 retina •
550 imaging/image analysis: clinical