Predictability of ab-interno trabeculectomy success in the subsequent eye: A contralateral eye comparison study

Background To determine whether the outcome of the first eye may serve as a predictor for intraocular pressure (IOP)-lowering effectiveness in the second eye following bilateral ab interno trabeculectomy. Methods This retrospective single-centre study included 168 eyes from 84 participants, who underwent combined Trabectome surgery with phacoemulsification cataract surgery in a hospital setting. The clinical endpoint was defined as either 'success' or 'failure' based on four separate scores at the longest follow-up time point: IOP at follow-up <21 mm Hg (Score A) or IOP < 18 mm Hg (Score B), without re-surgery and IOP reduction >20%; IOP <= 15 mm Hg without re-surgery and IOP reduction >= 40% (Score C); and the sole absence of re-surgery according to the discretion of the surgeon (Score D). Results No significant difference was observed between the outcomes of first and second eyes. The frequency of success in the second eye after effective surgery in the first eye significantly exceeded that after prior failure. Within our analysis, the probability calculations determined a 75% chance of success following prior success for Score A. If surgery in the first eye failed, the chance of success in the subsequent eye was 37%. The corresponding probabilities were 79% and 32% for Score B, 56% and 9% for Score C, and 99% and 50% for Score D. Conclusion The results of our study offer a useful tool to assess the success of subsequent eye surgeries based on the outcome in the initial eye, owing to the high predictive potential.

Automated summary

The study found that the outcome of the first eye surgery can be used as a useful tool to assess the success of subsequent eye surgeries, with high predictive potential.