Abstract
Purpose:
To analyze structural changes and macular morphology with Spectral Optical coherence tomography (SD OCT) and Fundus Autofluorescence (FAF) in patients with Stargardt’s disease (STGD1) and to correlate between visual acuity (VA) and macular patterns.
Methods:
Forty eyes of 20 patients, with mean age of 26.2 ± 12.7 years and with STGD1 phenotypes, underwent full ophthalmic examination with best corrected visual acuity (BCVA), fundus photography, FAF and SD-OCT imaging. The levels and the distribution of autofluorescence (AF) and atrophic lesions were evaluated. The different macular retinal layers were analyzed with SD-OCT and total retinal thickness was measured between the internal limiting membrane and the retinal pigment epithelium. Patients were separated in 2 groups one with BCVA ≥ 0.05 and the other with BCVA< 0.05.
Results:
We found 5 different patterns in FAF. Type A: Homogeneous high AF of the entire retina (2 eyes); Type B: Heterogeneous high and low retinal AF with low central AF (16 eyes); Type C: Numerous small areas of atrophy in heterogeneous low AF (4 eyes); Type D: A large an isolated central retinal atrophy (12 eyes); Type E: A central retinal atrophy but without foveolar involvement (6 eyes). Six different patterns were found in SD-OCT. Group I: Normal foveal depression and clivus, regular photoreceptor inner/outer segment junction line (IS/OS) with hyper reflectivity of outer nuclear layer (2 eyes). Group II: subnormal foveal depression and clivus, foveal disorganization and/or loss of IS/OS junction (11 eyes). Group III: absence of foveal depression and clivus, loss of the IS/OS junction and the photoreceptors layer (17 eyes). Group IV: Macular hole aspect (4 eyes). Group V: large retinal atrophy with macular layers disorganization (3 eyes). Group VI: Pseudo-coloboma image with large atrophy of all macular layers (3 eyes). Foveal thickness was significantly reduced in all patients with STGD1 (mean central retinal thickness: 107.92 ± 42 µm) excepted in group I with subclinical STGD1. There was a statistically significant correlation between autofluorescence pattern and SD-OCT pattern (p=0,03) and between BCVA and SD-OCT pattern (p=0,04).
Conclusions:
Both SD-OCT and FAF are useful in the management of STGD1. Correlation between structure and function should be useful in guiding selection of patients for future therapeutic trials.
Keywords: 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) •
696 retinal degenerations: hereditary •
585 macula/fovea