Surgery offers moderate visual recovery in primary congenital glaucoma

Combined trabeculectomy with trabeculectomy (CTT) confers benefits on patients with primary congenital glaucoma (PCG), suggests a study.

This retrospective study included 220 eyes of 121 patients undergoing surgery for PCG between January 1991 and December 2000 and who returned for follow-up from January 2021 through January 2022. The researchers reviewed the medical records of those who underwent CTT without mitomycin C.

Success was deemed “complete” when intraocular pressure (IOP) was ≥6 and ≤21 mm Hg without glaucoma medication and “qualified” when up to two glaucoma drugs were required. Failure referred to uncontrolled IOP with more than two glaucoma medications, need for a second IOP-lowering procedure, chronic hypotony (IOP <6 mm Hg on two consecutive visits), or any sight-threatening complication.

The research team used a mixed-effects model to estimate eye-based variables and to make comparisons between different visits. They performed Kaplan‒Meier survival analysis to estimate the probabilities of surgical and functional successes. Finally, Cox proportional hazards regression was conducted to assess risk factors for failure and poor visual outcome.

In Kaplan‒Meier survival analysis, complete success rates were 90.7 percent at 1 year, 78.9 percent at 10 years, and 44.5 percent at 20 years. Univariate analysis revealed higher surgical failure among patients with additional nonglaucoma intraocular surgery. In multivariable analysis, no clinical parameter significantly correlated with failure.

Among the eyes examined, 33.2 percent, 16.4 percent, and 50.4 percent achieved good, fair, and poor visual outcomes, respectively. Majority of the eyes (68.9 percent) also had myopia.

In patients who underwent primary CTT, 28 eyes (14.4 percent) required a second surgery for IOP control. Significant intraoperative complications did not occur. Additionally, six eyes had enucleation due to painful blind eye.

“CTT provides good IOP control and moderate visual recovery that remained over a 20-year follow-up after surgery,” the researchers said.