Clinical Findings in Four Siblings with Genetically Proven Oguchi Disease

Purpose: To assess the clinical findings in normal daylight status and 3 h of dark‑adapted status in family members with Oguchi disease (OD). Methods: Four siblings with OD and their parents were included in this case series. The presence of disease was confirmed with genetic analysis and comprehensive clinical evaluation. Corrected distant visual acuity (CDVA), automated visual field analysis (VFA), optical coherence tomography (OCT), OCT angiography (OCTA), colored fundus photography, fundus autofluorescence (FAF), fundus fluorescein angiography (FFA), electroretinography (ERG), and dark adaptation test (DAT) results were obtained in normal daylight status. On the next day, after 3 h of dark adaptation, the patients were re‑evaluated. The findings obtained in normal daylight status and 3 h dark‑adapted status were compared. Results: The mean age of the four sibling subjects was 15.25 ± 2.2 years. All subjects had 20/20 CDVA and normal VFA. There was no abnormality in OCT and OCTA in normal daylight status and 3 h of dark‑adapted status. Colored fundus photographs showed characteristic golden‑yellow colored reflex in the mid‑peripheral retina in normal daylight status, and discoloration in 3 h of dark‑adapted status. In FAF and FFA, no abnormal pattern was observed in normal daylight status and 3 h of dark‑adapted status. ERG showed rod function alterations and normal cone function. DAT showed delayed rod adaptation and normal cone adaptation. ERG and DAT findings remained unchanged after 3 h of dark adaptation. Conclusion: After 3 h of dark adaptation, golden‑yellow fundus color returns to normal in patients with OD; however, rod function alterations and normal cone function in ERG, as well as delayed rod adaptation and normal cone adaptation in DAT remain unchange.