Abstract
Abstract: :
Purpose: To study the central retinal disease expression in Best macular dystrophy (BMD), an autosomal dominant retinopathy caused by VMD2 mutations, using optical coherence tomography (OCT) and to relate these structural changes to changes in visual function. Methods: BMD patients (ages 5-61) with known VMD2 mutations were evaluated clinically with OCT. Longitudinal reflectivity profiles (LRPs) were quantified and used to identify the structural changes. Visual thresholds were also measured using automated perimetry. Results: BMD central retinas showed different OCT abnormalities at the level of the highly reflective deep retinal band termed the outer retina-choroid complex (ORCC). There were three types of change: (1) ORCC elevation with associated ORCC thickening/disruption and increased backscatter; (2) ORCC splitting with/without intervening hyporeflective areas and (3) ORCC and retinal thinning. ORCC elevation often occurred adjacent to ORCC splitting. These micropathological features were accompanied by functional changes. Thresholds were least affected by ORCC elevation, ORCC splitting resulted in moderate threshold elevation, and ORCC and retinal thinning was associated with the most severe dysfunction. Conclusion: Interpretation of the cross-sectional images of BMD, bolstered by limited histopathology but extensive clinical observations, suggests lesions can begin along the base of the RPE, disrupt these cells and their interface with the photoreceptors, lead to photoreceptor loss and central visual disturbance.
Keywords: 562 retinal degenerations: hereditary • 460 macula/fovea • 432 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)