Purpose:
To study angiographic retinal non-perfusion in diabetic retinopathy (DR) and explore its association with retinal neovascularization.
Methods:
Retrospective, observational case series. An imaging database of angiograms performed at a single academic institution was searched for patients with the diagnosis of DR. Ultra wide field fluorescein angiograms were graded with a previously published protocol for quantifying retinal non-perfusion by calculating an ischemic index (ISI), the presence of retinal neovascularization, and the presence of angiographic macular leakage. Charts were reviewed for demographic and clinical information.
Results:
Twenty seven patients were identified and 42 eyes studied; mean patient age was 63 years (SD 22, range 25-92). The mean ISI in all eyes was 34.81% (SD 27, range 1-99). The mean ISI in non-proliferative DR eyes was 15% +/- 21% (range 0%-74%). The mean ISI in proliferative DR eyes was 49% +/- 21% (range 21%- 98%). Increasing ISI was significantly correlated to retinal neovascularization (p>0.0001). An ISI>21% was 100% sensitive and 83% specific for the presence of retinal neovascularization
Conclusions:
Ultra wide field fluorescein angiography provides visualization of retinal non-perfusion in eyes with DR. Eyes which had retinal neovascularization at the time of the angiography were found to have significantly larger areas of retinal non perfusion as evidenced by a higher ISI compared to eyes without retinal neovascularization.
Keywords: diabetic retinopathy • ischemia • edema