Autoimmune retinopathy: findings and limitations from optical coherence tomography angiography.

BACKGROUND AND OBJECTIVE: To report novel findings and limitations from optical coherence tomography angiography (OCTA) in the evaluation of autoimmune retinopathy (AIR). STUDY DESIGN: We retrospectively reviewed features of five patients diagnosed with AIR and five controls. OCTA scans were obtained and manually segmented to provide accurate measurements of foveal avascular zone (FAZ), vessel density, and retinal thickness at different levels. RESULTS: The total retina and superficial vessel density throughout the whole scan were similar between AIR and controls (p = 0.14 and p = 0.11), whereas deep vessel density was decreased in AIR compared controls (p = 0.02). Decreased vessel density was most pronounced in the parafoveal and perifoveal areas (p = 0.01 and p = 0.01). AIR patients also had reduction of total retinal thickness in the perifoveal zone (p = 0.03), corresponding to outer retinal thinning (p = 0.001). CONCLUSION: This small series shows that AIR patients have reduced deep vessel density, particularly in the parafoveal and perifoveal regions and a decrease in macular thickness. These findings show correlation with the classic "flying saucer" sign seen on OCT.