Abstract:Objective To explore the diagnostic value of optical coherence tomography angiography（OCTA）combined with fundus fluorescein angiography（FFA）in assessing the severity of diabetic retinopathy. Methods A retrospective study included 831 diabetic patients who visited the General Hospital of Southern Theater Command from January 2021 to December 2023. All patients underwent OCTA and FFA examinations，and relevant indicators were collected. Using fundus examination as the gold standard，the sensitivity，specificity，and accuracy of OCTA，FFA，and their combination in diagnosing the severity of DR lesions were analyzed，with Kappa values used for consistency analysis.Based on the results of the fundus examination，the patients were divided into the PDR group（proliferative diabetic retinopathy，n=164），NPDR group（non - proliferative diabetic retinopathy，n=437），and NDR group（no diabetic retinopathy，n=230）. The retinal nerve fiber layer thickness（RNFL）and subfoveal choroidal thickness（SFCT）were compared among patients with different severities of diabetic retinopathy. Results The combined detection of OCTA and FFA showed higher sensitivity and specificity in assessing the severity of diabetic retinopathy compared to single tests，and were highly consistent with the gold standard. Significant differences in RNFL and SFCT were observed among different severity groups（P < 0.01）. In the NDR group，RNFL and SFCT were higher than those in the PDR and NPDR groups，respectively（P < 0.05）. RNFL and SFCT in the NPDR group were also higher than those in the PDR group（P < 0.05）. Conclusion The combined detection of OCTA and FFA has certain diagnostic value in assessing the severity of diabetic retinopathy.