ObjectiveTo evaluate macular microvessel changes in familial exudative vitreoretinopathy (FEVR) by optical coherence tomography angiography. MethodsCross-sectional clinical case-control study. From November 2019 to November 2020, 21 FEVR patients (41 eyes) from Weifang Eye Hospital were selected; 17 healthy volunteers (28 eyes) with the same age and gender as FEVR group were selected as normal control group. According to the best corrected visual acuity (BCVA) 1.0 and ＜1.0, FEVR group was divided into normal visual acuity group (27 eyes) and visual acuity decreased group (14 eyes). All enrollees received BCVA and OCTA. BCVA was performed with an international standard visual acuity chart, which was converted to logarithm of the minimum angle of resolution (logMAR) vision. The OCTA instrument was used to scan the macular area of all the examined eyes in the range of 3 mm×3 mm, 6 mm×6 mm, and the blood vessel density (VD) and blood perfusion density (PD) within the range of 3 mm×3 mm, 6 mm×6 mm were measured and the area, circumference, and morphological index of the foveal avascular zone (FAZ) within the range of 6 mm×6 mm. Quantitative data were compared between groups by independent sample t test. Statistical data were compared by χ2 test. The area under curve (AUC) of each index was determined according to receiver operating characteristic curve (ROC curve), and the predictive value of each index was evaluated. ResultsIn the macular area of 6 mm×6 mm, VD, PD, FAZ area and FAZ perimeter of FEVR group were all lower than those of normal control group, and the differences were statistically significant (t=−3.350, −2.387, −3.519, −3.029; P＜0.05). In macular area of 3 mm×3 mm and 6 mm×6 mm, compared with normal vision group and vision loss group, both VD and PD decreased. The differences were statistically significant (t=2.088, 2.114, 2.160, 2.545; P＜0.05). In the macular area of 6 mm×6 mm , the FAZ morphological index of the two groups was significantly different (t=2.409, P＜0.05). ROC curve analysis showed that all the indicators had low diagnostic value for FEVR (AUC＜0.5). ConclusionThere are microvascular abnormalities in macular area in FEVR patients, and the decrease of blood vessels and the change of FAZ shape may be related to the loss of visual acuity.