Peripapillary Versus Macular Thinning to Detect Progression According to Initial Visual Field Loss Location in Normal-Tension Glaucoma

Am J Ophthalmol. 2024 May 18:S0002-9394(24)00214-9. doi: 10.1016/j.ajo.2024.05.012. Online ahead of print.

Abstract

Purpose: To investigate the predictive capabilities of peripapillary retinal nerve fiber layer (pRNFL) and macular ganglion cell-inner plexiform layer (mGCIPL) thinning to detect visual field (VF) progression in normal-tension glaucoma patients with an initial parafoveal scotoma (IPFS) or nasal step (INS).

Design: Retrospective cohort study.

Methods: 185 early-stage glaucoma eyes, followed for 10 years, were retrospectively stratified into IPFS and INS groups. Progressive pRNFL and mGCIPL thinning were assessed using spectral-domain optical coherence tomography and VF progression using both event- or trend-based analysis. Kaplan-Meier survival analysis compared VF survival in each VF phenotype with or without progressive pRNFL and mGCIPL thinning. Cox proportional regression analysis identified VF progression factors.

Results: VF progression was detected in 42 IPFS (n=86) and 47 INS (n=99) eyes. Among VF progressors, pRNFL thinning was significantly faster in INS group compared to IPFS group (P < 0.01), while mGCIPL thinning was similar (P = 0.16). At five years, eyes with progressive mGCIPL thinning showed significantly lower VF survival in both VF phenotypes (all P < 0.05). Progressive pRNFL thinning showed significantly lower VF survival only in INS eyes (P = 0.015). Cox multivariate regression revealed that mGCIPL thinning predicted subsequent VF progression in IPFS eyes, while mGCIPL and pRNFL thinning had significant associations with VF progression in INS eyes.

Conclusions: mGCIPL outperforms pRNFL at early follow-up in detecting VF progression in IPFS eyes but not INS eyes. Appropriate selection of structural parameters (mGCIPL vs pRNFL) maximizes early VF progression detection according to initial VF defect location.

Keywords: Normal-tension glaucoma; ganglion cell-inner plexiform layer; guided progression analysis; initial nasal step; initial parafoveal scotoma; retinal nerve fiber layer.