Advanced imaging of corneal neovascularisation with a novel swept-source AS-OCTA system.

Abstract

To explore the clinical application of a novel swept-source anterior segment optical coherence tomography angiography (AS-OCTA) system for imaging corneal neovascularisation (CoNV), assessing limbal vasculature and detecting short-term vascular changes following pharmacologic vasoconstriction. This cross-sectional observational study included 20 eyes: 10 with clinically diagnosed CoNV of various aetiologies and 10 healthy controls. Each eye underwent AS-OCTA imaging using the BMizar 400kHz Full-Range Swept-Source OCT system at baseline and after administration of 10% phenylephrine (PE). FlowArea (mm²) was automatically calculated across predefined circular regions of interest (ROIs) encompassing the cornea, limbus and episclera. In corneal and limbal ROIs, en face images were segmented into three depth layers: total (epithelium to endothelium), superficial (epithelium to 150 µm) and deep (150 µm to endothelium). CoNV eyes exhibited significantly higher total and deep corneal FlowArea compared with controls (p=0.0002 and p=0.0005, respectively). Post PE, a significant reduction in FlowArea was observed in the total and deep corneal layers of CoNV eyes (p=0.006 and p=0.009, respectively), and in the limbal region of both groups, with significant reductions observed in CoNV and controls (p=0.006 and p=0.003, respectively). This AS-OCTA platform enabled high-resolution, depth-resolved visualization of CoNV and revealed vascular changes following topical vasoconstriction. The extended field of view allowed simultaneous assessment of corneal, limbal and episcleral vasculature within a single scan session, supporting its potential role in both diagnostic evaluation and longitudinal monitoring of anterior segment diseases.