Evaluation of peripapillary capillary perfusion density in relation to homocysteine levels in patients with pseudoexfoliation syndrome

This study aimed to investigate the effect of plasma homocysteine levels on peripapillary microvascular perfusion in individuals with pseudoexfoliation syndrome (PEX). PEX is increasingly considered not only an ocular condition but also a systemic disease with vascular involvement. Elevated homocysteine, known to impair endothelial function and promote vascular damage, may contribute to microcirculatory disturbances in the optic nerve head. Optical Coherence Tomography Angiography (OCTA), a non-invasive imaging modality, was used to evaluate peripapillary vessel density and its relationship with homocysteine levels. The prospective study included 60 participants (97 eyes) aged between 45 and 90 years, who were divided into three groups: PEX patients with normal homocysteine levels, PEX patients with elevated homocysteine levels, and PEX-free controls. Comprehensive ophthalmological assessments, including intraocular pressure, retinal nerve fiber layer (RNFL) thickness, macular measurements, and optic disc parameters, were performed using OCT and OCTA. Plasma homocysteine levels were measured via chemiluminescent immunoassay. Findings revealed a significant reduction in peripapillary vessel density (both VAD and VLD) among PEX patients with elevated homocysteine levels. This group also exhibited higher intraocular pressure compared to controls. A negative correlation was observed between homocysteine levels and peripapillary microvascular density, and this relationship appeared more pronounced in patients with coexisting systemic diseases such as hypertension and diabetes. The results suggest that homocysteine may play a critical role in the pathogenesis of PEX by contributing to microvascular impairment around the optic nerve. OCTA-derived vascular parameters may serve as useful biomarkers for early detection of glaucomatous changes and risk stratification in PEX patients.