BackgroundTo perform the optical coherence tomography angiography (OCT-A) evaluation of the microvascular structures of the retina and choroidal tissue in asymptomatic patients who received radiotherapy for nasopharyngeal carcinoma and to compare the results to those of healthy individuals. MethodsOphthalmological examinations were performed in all asymptomatic patients without vascular or systemic diseases, or fundus findings who had received radiotherapy at least two years earlier. Then, OCT-A scans were obtained. Foveal, parafoveal, and whole retinal thicknesses, vessel densities in the superficial and deep capillary plexuses, subfoveal choroidal thickness, the non-flow area in the superficial capillary plexus, and the choriocapillaris flow area were measured and compared to the values of the healthy control group. ResultsThe radiotherapy group had significantly lower deep capillary plexus vascular density and subfoveal choroidal thickness values and significantly higher choriocapillaris flow area values compared to the control group. ConclusionsWe consider that OCT-A is useful in the early diagnosis of radiation retinopathy that may develop during follow-up in patients with nasopharyngeal carcinoma who have received radiotherapy.