Optical coherence tomography angiography findings before and after onset of foveal retinal neovascularization in diabetic retinopathy

PURPOSE: To report a rare case of foveal retinal neovascularization (RNV) in a patient with diabetic retinopathy in whom the retinal microcirculation structure before and after the onset of the disease was evaluated using optical coherence tomography angiography (OCTA). OBSERVATIONS: A 54-year-old woman with diabetes mellitus was referred to our department for fundus evaluation, and was diagnosed with cataract and severe non-proliferative diabetic retinopathy in the left eye. Two years after we performed cataract surgery and pan-retinal photocoagulation in the left eye, OCTA detected a previously unidentified foveal RNV arising from the perifoveal capillary network. The vitreous retinal interface slab of OCTA and cross-sectional OCT images confirmed that this foveal RNV was an aberrant vessel invading the vitreous cavity. CONCLUSIONS AND IMPORTANCE: The findings in this case indicate that foveal RNV in diabetic retinopathy is derived from vessels outside the foveal avascular zone (FAZ), and OCTA is a useful examination for the diagnostic investigation of foveal RNV.