Multilayer Macula Vessel Density and Visual Field Progression in Glaucoma

Abstract

Purpose: To evaluate the association of macular superficial vessel density (SVD) and projection-resolved deep vessel density (DVD) with past visual field (VF) progression in patients with primary open-angle glaucoma.

Design: Retrospective cohort.

Methods: In this longitudinal study, 208 eyes of 147 patients with glaucoma from the Diagnostics Innovations in Glaucoma Study were included. Eligible participants were required to have at least five 24-2 VF tests over a minimum follow-up period of 3 years before macular optical coherence tomography angiography imaging. VF progression was defined based on both event-based pointwise linear regression and trend-based methods. The association of macular SVD and DVD with the probability and rate of past VF progression was evaluated using a linear mixed effects model.

Results: Fifty-two (25%) eyes had VF progression based on the pointwise linear regression based criterion at the end of a mean ± standard deviation follow-up duration of 6.9 ± 1.2 years. In the event-based multivariable analysis, a lower baseline SVD was associated with a higher likelihood of past VF progression (odds ratio per 1% lower. 1.28; 95% confidence interval, 1.02-1.59). Similarly, in the trend-based multivariable analysis, lower macular SVD was associated with a faster past rate of mean deviation decline (coefficient = -0.03 dB/year; 95% confidence interval, -0.04 to -0.01). Event-based and trend-based analyses found no significant associations for macular DVD with the likelihood/rate of past VF progression (P > .05).

Conclusions: Lower macular SVD, and not DVD, was associated with a higher probability of past VF progression. Macular optical coherence tomography angiography imaging shows promise for identifying eyes at risk of VF progression in patients with glaucoma.

Figure 1.

Classification performance of superficial vessel density (SVD) and deep vessel density (DVD) [A], and ganglion cell complex (GCC) thickness (B) in the discrimination of eyes with and without visual field progression defined by pointwise linear regression event-based criterion. The classification accuracy is represented as the area under the receiver operating characteristic curve (AUROC) [95% CI].

Figure 2.

“A” shows series of 24-2 visual field tests and their corresponding mean deviation (MD) values for one of the study participants with visual field progression (based on pointwise linear regression criterion) from 2011 to 2019. “B”, and “C” shows en-face Optical Coherence Tomography Angiography (OCTA) images of the same participant at the end of the study follow-up. “B1” and “C1” show the actual enface OCTA images segmented at the superficial and the deep vascular layers, respectively. The respective vessel density (VD) measurements are shown on the top of each image. “B2” and “C2” show the corresponding color-coded heatmaps of the same en-face OCTA images. Note that, some degrees of residual projection artifacts are still visible in the deep vascular layer (as demarcated by arrows in “C1”) even after the implementation of the projection-resolved algorithm.