Objective To explore the relationship between optic nerve tissue thickness and enlarged perivascular space(EPVS)in patients with recent small subcortical infarct(RSSI).Methods A total of 72 RSSI patients admitted to Department of Neurology of Changzhou Second People's Hospital affiliated to Nanjing Medical University from November 2021 to December 2022 were re-cruited in this study.All patients underwent cranial MRI,optical coherence tomography(OCT)and fundus photography.The thickness of retinal nerve fiber layer(RNFL)and ganglion cell-inner plexiform layer(GCL-IPL)were measured by software semi-automatic segmentation,and fundus lesions such as fundus hemorrhage and exudation were observed through fundus photography.The severity of EPVS was graded by visual quantitative evaluation,and then the patients were divided into no to mild EPVS group(32 cases)and moderate to severe EPVS group(40 cases).Basal gan-glia EPVS(BG-EPVS)and semioval center EPVS(CSO-EPVS)were further graded and grouped into no to mild BG-EPVS group(31 cases)and moderate and severe BG-EPVS group(41 cases),and no to mild CSO-EPVS group(39 cases)and moderate and severe CSO-EPVS group(33 cases).The clinical data of each group were compared separately.Results There were statistical differences in age,ratio of hypertension and thicknesses of RNFL and GCL-IPL between the no to mild EPVS group and the moderate to severe EPVS group(P＜0.05,P＜0.01),between the no to mild BG-EPVS and the moderate to severe BG-EPVS group(P＜0.01).Multivariate logistic re-gression analysis showed that age(OR=1.207,95％CI:1.028-1.416,P=0.021),hypertension(OR=7.264,95％CI:1.079-11.929,P=0.042),RNFL thickness(OR=0.753,95％CI:0.617-0.915,P=0.004)and GCL-IPL thickness(OR=0.848,95％CI:0.758-0.949,P=0.004)were independent factors of BG-EPVS grade.Spearman correlation analysis indicated that the thicknes-ses of RNFL and GCL-IPL were negatively correlated with BG-EPVS grade(r=-0.571,r=-0.649,P＜0.01).Conclusion RNFL and GCL-IPL thicknesses are independent factors for BG-EPVS grade and negatively correlated with BG-EPVS grade.OCT has important clinical value in assessing the severity of EPVS lesions in RSSI patients.