Purpose
To report a novel finding of foveal SD-OCT hyper-reflectivity extending above the external limiting membrane which may precede photoreceptor atrophy in eyes with Stargardt Disease.
Methods
This was a retrospective review of SD-OCT and fundus autofluorescence imaging from 3 institutions. Imaging of both Stargardt patients and of their asymptomatic siblings, some having genetic confirmation of their diagnosis, were analyzed.
Results
Six patients were identified as having the novel SD-OCT biomarker including 2 asymptomatic young siblings (4 and 5 yrs old) of an 8-year-old boy with genetically confirmed Stargardt disease and 20/200 VA. Ultra-widefield autofluorescece (UWF-AF) imaging showed mildly increased FAF in the young siblings and marked hyper-AF in the 8 year-old with clinical findings. Additional cases included a 23-year-old (VA 20/25) and a 27-year-old (VA 20/200), both with genetic confirmation of Stargardt disease. The SD-OCT abnormality was not detected in any Stargardt patient over 40 yrs.
Conclusions
The proposed SD-OCT biomarker appears to be present prior to symptomatic vision loss in patients as young as 4 yrs. We hypothesize that cellular degeneration at the level of the outer nuclear layer may produce this finding. The biomarker is likely transient and may be lost with further outer retina degeneration.
Keywords: 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) •
696 retinal degenerations: hereditary •
539 genetics