Purpose:
In this study we have 2 main objectives: i) to study the peripheral angiographic features of patients with recalcitrant diabetic macular edema (DME) and peripheral retinal nonperfusion in non-proliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR) and ii) to demonstrate the diagnostic value of wide-field fluorescein angiography in elucidating the role of subtle peripheral pathology in diabetic retinopathy.
Methods:
This is a retrospective observational case series of approximately 50 eyes of 100 patients who have been diagnosed with DME for at least 2 years at a single academic institution. Protocols were approved by the institutional review board at the study site, and consent was obtained from each patient. A retrospective review of all Optos wide-field fluorescein angiograms and spectral domain OCT (SD-OCT) was performed at baseline (1 clinic visit). Three study cohorts were enrolled. Cohort 1 (control) subjects were diagnosed with NPDR without DME or peripheral ischemia. Cohort 2 subjects were diagnosed with NPDR with DME or peripheral ischemia. Cohort 3 subjects diagnosed with PDR and DME with or without previous pan retinal photocoagulation (PRP).
Results:
Our preliminary data demonstrates an increased incidence of peripheral nonperfusion on Optos wide-field fluorescein angiography with recalcitrant DME (on SD-OCT) in all non-control cohorts. Further statistical analysis is to follow. Also, the diagnostic value of the wide-field fluorescein angiogram was demonstrated by detecting subtle peripheral neovascularization that was not found on clinical exam.
Conclusions:
Wide-field fluorescein angiography is an excellent diagnostic instrument that provides a reproducible method to detect subtle peripheral neovascularization in diabetic retinopathy. Areas of untreated retinal nonperfusion may generate biochemical mediators that promote ischemia with or without neovascularization and recalcitrant DME. Targeted retinal photocoagulation will show improvement or resolution of recalcitrant DME.
Keywords: diabetes • macula/fovea • edema