Reevaluating the Definition of Intraretinal Microvascular Abnormalities and Neovascularization Elsewhere in Diabetic Retinopathy Using Optical Coherence Tomography and Fluorescein Angiography

Abstract

To evaluate the agreement between clinical examination, spectral-domain ocular coherence tomography (SD OCT), and fluorescein angiography (FA) in diagnosing intraretinal microvascular abnormality (IRMA) and neovascularization elsewhere (NVE) and define the SD OCT features that differentiate NVEs from IRMAs. Retrospective study. Data were collected from 23 lesions from 8 diabetic patients, seen from July 2012 through October 2013 at Moorfields Eye Hospital, United Kingdom. Main outcomes were SD OCT features and FA leakage of IRMA and neovascular complex. The agreement between 3 evaluations was analyzed by Fleiss' kappa. The following 5 SD OCT features significantly differentiated IRMAs from NVEs: (1) hyperreflective dots in superficial inner retina (P = .002); (2) the outpouching of internal limiting membrane (ILM) (P = .004); (3) the breach of ILM (P = .004); (4) the breach of posterior hyaloid (P = .0005); (5) hyperreflective dots in vitreous (P = .008). The agreement was moderate between 3 evaluations (κ = 0.48, P = 7.11 × 10(-5)) but substantial between clinical and SD OCT evaluation (κ = 0.72, P = .00055). There was no significant agreement between OCT evaluation and FA leakage (κ = 0.249, P = .232). SD OCT will be a valuable adjunct in evaluating IRMA and NVE, since it can verify the histopathologic correlate. SD OCT provides subtle anatomic insights and may be more accurate than clinical examination or leakage on FA, our current method of diagnosing this important endpoint, which has implications in future trial design for proliferative diabetic retinopathy prevention.