Structure-Function Correlation of Virtual Reality and Standard Perimetry With Peripapillary RNFL OCT in Glaucoma Patients

Purpose: To compare the structure-function relationship of a virtual reality-based visual field test (Radius XR) with standard automated perimetry using either the SITA Fast or SITA Faster strategy, based on peripapillary retinal nerve fiber layer (pp-RNFL) thickness measured by spectral-domain optical coherence tomography (SD-OCT). Methods: This cross-sectional study included 116 eyes from 71 patients with glaucoma or suspected glaucoma. Participants underwent 24-2 visual field testing with Radius XR (RATA Fast) and a single standard automated perimetry strategy (either SITA Fast or SITA Faster). Peripapillary RNFL thickness was measured with SD-OCT within six months. Global and sectoral structure-function relationships were evaluated using linear mixed-effects models, with visual field locations mapped to corresponding peripapillary RNFL sectors based on the Garway-Heath map. Results: Structure-function associations between global pp-RNFL thickness and mean deviation were observed across testing modalities, with marginal R² values of 0.36 for Radius XR (RATA Fast), 0.43 for SITA Fast, and 0.29 for SITA Faster derived from linear mixed-effects models. Sectoral analyses demonstrated the strongest associations in the supratemporal and inferotemporal regions across all modalities. Conclusions: Radius XR achieved structure-function correlations comparable to standard automated perimetry, particularly in clinically relevant RNFL sectors, supporting its role in glaucoma assessment. Translational Relevance: Virtual reality-based perimetry provides structure-function relationships consistent with standard perimetry while improving accessibility, facilitating broader integration of functional testing into clinical and community-based glaucoma care.