Factors associated with vision loss in Black or Hispanic patients 1 year after standalone or combined Ahmed glaucoma valve surgery

Abstract

Purpose: To determine factors associated with vision loss 1 year after Ahmed glaucoma valve (AGV) surgery in Black or Hispanic patients, who bear disproportionate glaucoma burdens yet have been underrepresented in pivotal trials.

Methods: This retrospective study included Black or Hispanic patients who received AGVs standalone or combined with phacoemulsification and/or cyclodestructive lasers. Univariate and multivariate generalized estimating equations evaluated the effects of baseline, surgical, and postoperative factors on vision loss of two Snellen lines or more at the 1-year follow-up visit. The primary term was the hypertensive phase (HP), which signified an intraocular pressure (IOP) reading > 21 mmHg within the first 3 postoperative months after reduction below 22 in the first week, without other tube malfunction.

Results: Of 241 eyes from 186 patients, vision loss of ≥ 2 lines at the 1-year follow-up visit occurred in 21.6% (N = 52). Vision loss of ≥ 2 lines occurred in 52.5% of eyes at week 1, 36.9% of eyes at month 1, and 27.0% of eyes at month 3. Between 6 months and 1 year, vision loss frequencies stabilized. In the multivariate model, HP (OR = 4.71 (2.14, 10.38)), total quadrants with split fixation (1.47 (1.20, 1.81)), follow-up non-glaucomatous eye pathology (2.89 (1.44, 5.80)), and concurrent cataract surgery (0.42 (0.22, 0.82)) each met significance (p < 0.05).

Conclusion: Post-AGV vision loss in the early follow-up period among Black or Hispanic patients was often transient. Hypertensive phase and split fixation each increased the odds of vision loss at 1 year, while concurrent cataract surgery decreased the odds.

Keywords: Ahmed glaucoma valve; Disparities; Glaucoma surgery; Hypertensive phase; Tube shunt; Visual acuity.