Detection of Neovascularisation in the Vitreoretinal Interface Slab Using Widefield Swept-Source Optical Coherence Tomography Angiography in Diabetic Retinopathy

BACKGROUND/AIMS: To compare the efficacy of diabetic retinal neovascularisation (NV) detection using the widefield swept-source optical coherence tomography angiography (WF SS-OCTA) vitreoretinal interface (VRI) Angio slab and SS-OCT VRI Structure slab. METHODS: A prospective, observational study was performed at Massachusetts Eye and Ear from January 2019 to June 2020. Proliferative diabetic retinopathy (PDR), non-proliferative diabetic retinopathy (NPDR) and diabetic patients with no diabetic retinopathy were included. All patients were imaged with WF SS-OCTA using the 12- x 12-mm Angio scan protocol centred on the fovea and optic disc. The en-face SS-OCTA VRI Angio slab and SS-OCT VRI Structure slab were evaluated for the presence or absence of NV. SS-OCTA B-scan was used to classify NV according to cross-sectional morphology (forward, tabletop, or flat). All statistical analyses were performed using SPSS V.26.0. RESULTS: One hundred and forty-two eyes of 89 participants were included in the study. VRI Angio detected NV at higher rates compared to VRI Structure (P < .05). Combining VRI Angio and Structure improved detection rates compared to VRI Angio alone (P < .05). Due to segmentation errors of the ILM, NV with flat morphological classification had lower rates of detection on VRI Angio compared to NV with forward and tabletop morphology (P < .05). CONCLUSIONS: WF SS-OCTA 12- x 12-mm VRI Angio and SS-OCT VRI Structure imaging centred on the fovea and optic disc detected NV with high sensitivity and low false positives. The VRI slab may be useful to diagnose and monitor PDR in clinical practice.