Comparative analysis of ultra-wide-field fluorescein angiography and early treatment diabetic retinopathy study 7 standard field photography in diabetic retinopathy

Abstract

Objective To observe the ocular fundus features and consistency of classification of diabetic retinopathy (DR) by ultra-wide-field fluorescein angiography (UWFA) and the simulated early treatment diabetic retinopathy study (ETDRS) 7 standard field (7SF) imaging. Methods This is a retrospective clinical description study. Ninety-six eyes of 55 DR patients were included. The ages ranged from 25 to 73 years, with a mean age of (41.34±15.07) years. UWFA examination (British Optos 200Tx imaging system) using the protocol for obtaining 7SF images as described in the ETDRS, 7 circular regions with a range of 30 degrees are spliced as 7SF templates to determine the observation range. This template was then overlaid on the UWFA image to identify the potential viewable area of 7SF. And the visualized area of the retina, retinal non-perfusion (NP) area, retinal neovascularization (NV) area, and pan-retinal photocoagulation (PRP) area of UWFA and 7SF were quantified by a retinal specialist. Results UWFA imaging and 7SF imaging have a high degree of consistency in judging DR classification (kappa=0.851, P=0.000). The retinal visual area, NP area, NV area and PRP area of the UWFA imaging were 3.16, 3.38, 2.22 and 3.15 times more comparing with the simulated 7SF imaging (t=213.430, 45.013, 22.644, 142.665; P=0.000, 0.000, 0.003, 0.000). The lesions of 8 eyes were found outside the range of simulated 7SF imaging, including peripheral NP in 5 eyes, NV areas in 3 eyes, respectively. Conclusion UWFA imaging and simulated 7SF imaging are consistent to judge DR classification, but UWFA can find more peripheral retinal lesions. Key words: Diabetic retinopathy/diagnosis; Fluorescein angiography; Tomography, optical coherence