Application of iris angiography combined with ultra-wide-field fundus fluorescein angiography in diabetic retinopathy

Abstract

Objective: To explore the application and value of iris angiography combined with ultra-wide-field fundus fluorescein angiography (UWFA) in diabetic retinopathy (DR). Methods: This was a cross-sectional study. From May 2016 to December 2019, 60 consecutive DR patients (120 eyes) including 30 patients (60 eyes) with severe non-proliferative DR (NPDR) and proliferative DR (PDR), respectively, who underwent iris angiography combined with UWFA in Tianjin Medical University Eye Hospital were enrolled in the study. There were 25 males and 35 females, with an average age of (53.5±10.7) years. All of the patients underwent ophthalmologic examination including visual acuity, intraocular pressure, slit-lamp microscopy, slit-lamp funduscopy, ultra-wide-field fundus photography, and iris angiography combined with UWFA. Iris angiography included iris fluorescein angiography (IFA) and iris indocyanine green angiography. The onset time of the iris vascular fluorescein leakage was recorded, and the circumference range of the pupil margin fluorescein leakage was measured by a self-developed software. Wilcoxon rank sum test was used to compare and analyze the difference in the onset time and the range of the iris vascular fluorescein leakage between the severe NPDR and PDR groups. Results: IFA showed that the onset time of the iris vascular fluorescein leakage was 31.00 (25.75, 34.00) s and 27.00 (21.75, 29.50) s in the severe NPDR group and the PDR group, respectively. The difference between two groups was statistically significant (Z=-2.13, P=0.033). The range of the iris vascular fluorescein leakage was 20.00(10.75, 75.00)° and 135.00(60.00, 182.50)° in the severe NPDR group and the PDR group, respectively. There was significant difference between two groups (Z=-4.23, P<0.001). Neovascularization of the iris was not found in all patients with PDR by slit-lamp microscope examination, but was found in 8 eyes by IFA and iris indocyanine green angiography. UWFA findings demonstrated that there was no strong fluorescence in retinal neovascularization elsewhere and/or neovascularization of the optic disc in severe NPDR patients. However, that could be seen in all PDR patients. Among them, 10 eyes had terminally petaloid or focal fluorescein leakage in macular area. Conclusions: Iris angiography combined with UWFA and quantitative analysis method could not only accurately assess the degree of fundus lesions, but also obtain more accurate and comprehensive iris vascular information, which provided help for comprehensive and personalized treatment of DR. (Chin J Ophthalmol, 2021, 57: 916-921).