Progression in Preperimetric Glaucoma Eyes With and Without Microvasculature Dropout

To investigate whether baseline microvasculature dropout (MvD) is associated with subsequent structural and functional changes in preperimetric glaucoma.

Subgroup analysis of prospective cohort study data.

This study included 93 eyes from 70 participants with a glaucomatous optic disk appearance but no repeatable visual field defects, who were followed with optical coherence tomography, optical coherence tomography angiography, and visual field (VF) over a mean of 4.9 years. Circumpapillary retinal nerve fiber layer thickness and circumpapillary capillary density (cpCD) were assessed. Eyes were grouped based on the presence or absence of MvD at baseline. Mixed-effects models were used to identify factors associated with structural and functional progression.

Mean age was 67.7 (95% CI, 65.4-70.0) years. Among the 93 eyes, those with baseline MvD (32 eyes) showed faster loss of cpCD (-0.88 [95% CI, -1.08 to -0.67] %/year) compared to eyes without MvD (-0.23 [95% CI, -0.42 to -0.04] %/year). In multivariable models, the presence of MvD was independently associated with faster cpCD loss (-0.63 [95% CI, -0.95 to -0.32] %/year, P < .001). In contrast, it was not associated with circumpapillary retinal nerve fiber layer loss (0.03 [95% CI, -0.33 to 0.38] µm/year, P = .886). Moreover, PPG eyes that had MvD at baseline developed VF loss more frequently than those without MvD. (62.5% vs 26.2%, P < .001).

Baseline MvD in PPG is associated with both faster vessel density loss and subsequent VF loss, and higher rates of developing glaucomatous visual field damage. Assessment of MvD can be used to estimate risk and guide the frequency of follow-up in patients with PPG.