Non-invasive evaluation of diabetic retinal neovascularization using 24×20 mm ultra-widefield optical coherence tomography angiography

PURPOSE: To compare the efficacy of detecting diabetic retinal neovascularization (NV) by single captured 24×20mm ultra-widefield optical coherence tomography angiography (UWF-OCTA) with ultra-widefield color fundus photography (UWF-CFP) and ultra-widefield fluorescein angiography (UWF-FA). METHODS: This cross-sectional study included eyes with diabetic retinopathy (DR) undergoing UWF-FA, UWF-CFP, and UWF-OCTA at Guangdong Provincial People's Hospital (February 2022-May 2023). Images were captured using the Optos California system for UWF-CFP and UWF-FA, and the Toward Pi BM400K system for UWF-OCTA. NV was graded based on defined criteria for each imaging modality, with FA serving as the gold standard. The intraclass correlation coefficient (ICC), specificity and sensitivity were analyzed by SPSS v19. ICC assessed agreement between UWF-OCTA and the other modalities, while specificity and sensitivity were calculated using UWF-FA as the reference. RESULTS: Among ninety eyes (56 participants), UWF-OCTA demonstrated high sensitivity (0.97), specificity (1.0), and accuracy (0.99) for NV detection. UWF-OCTA and UWF-FA showed excellent agreement in NV count within the 24×20 mm field (ICC=0.994, P<0.001) and in total number (ICC=0.904, 95%CI: 0.742-0.959, P<0.001). Combing UWF-OCTA and UWF-CFP panoramically improved NV detection(ICC=0.988, 95%CI: 0.975-0.994, P<0.001). CONCLUSIONS: 24×20 mm UWF-OCTA is highly effective for NV detection, with excellent agreement to UWF-FA. Combined with UWF-CFP, it serves as a reliable, non-invasive alternative to FA for DR evaluation.