Risk factors for tube exposure following Baerveldt glaucoma implantation and overlying tissue thickness assessed by...

We identified clinical factors associated with tube exposure following Baerveldt glaucoma implantation (BGI) and used anterior segment optical coherence tomography (AS-OCT) to assess postoperative tissue thickness over the tube.

Retrospective, single-center cohort study.

In this single-center retrospective cohort study, 405 eyes underwent BGI (BG101-350) with preserved scleral patch grafts between October 2014 and December 2022. Tube exposure was documented through clinical records and slit-lamp examination. Risk factors were evaluated using Firth's penalized logistic regression. Overlying tissue thickness at 1 year postoperatively was measured via AS-OCT, and its association with clinical variables was analyzed using linear regression.

The mean follow-up was 630.7 days, and tube exposure occurred in 12 eyes (2.96%). Neovascular glaucoma (NVG) (odds ratio [OR] 5.03, p = 0.033) and anterior chamber (AC) tube insertion (OR 6.07, p = 0.017) were independently associated with exposure. Overlying tissue was significantly thinner with AC insertion compared with ciliary sulcus or pars plana placement (Kruskal-Wallis with Bonferroni-adjusted Dunn's tests; AC vs sulcus, p = 0.039; AC vs pars plana, p < 0.001). Among eyes with AC insertion, prior micropulse transscleral cyclophotocoagulation (MP-CPC) was associated with greater tissue thickness (estimate 0.173; p = 0.032).

AC insertion and NVG were associated with an increased risk of tube exposure after BGI. AS-OCT revealed thinner tissue over AC-placed tubes, providing a structural basis for this risk. Avoiding AC insertion may reduce exposure; the observed association between prior MP-CPC and thicker tissue requires prospective validation.