Two-year Results of Gonioscopy-assisted Transluminal Trabeculotomy in Primary Congenital Glaucoma.

ABSTRACT

PRECIS Gonioscopy-assisted transluminal trabeculotomy yielded a 45% reduction in intraocular pressure in primary congenital glaucoma, with a success rate of 86.6%. Hyphema was the most common complication. We did not encounter any vision-threatening complications. BACKGROUND: To assess the outcome of gonioscopy-assisted transluminal trabeculotomy (GATT) in primary congenital glaucoma (PCG) and identify the potential prognostic factors for adverse outcomes. METHODS: This prospective study included patients aged <14 years, presenting with PCG from November 2019 till November 2021. We excluded eyes with hazy cornea, secondary glaucoma, peripheral anterior synechiae ≥ 90°, and eyes in which the extent of GATT was <270°. Success was defined as a final intraocular pressure (IOP)<18 mmHg with IOP reduction>20%. Primary outcomes were reduction in IOP and medications, secondary outcomes were complications and correlation of IOP reduction and surgical success with possible risk factors. RESULTS: We included 60 eyes of 50 patients aged 1-156 months (mean 25.5±36.5). A 353°±21° incision was created, with 85% achieving a 360° incision. There was a significant reduction in IOP and medications at all follow-up intervals up to 2 years, with a mean of 45% IOP reduction. The final success rate was 86.6%, with 76.7% being controlled without medications. There was a significant positive correlation between the preoperative cup-to-disc ratio (CDR) and failure rates (P=0.03) and between the incision extent and the IOP reduction (r=0.4, P=0.001). Hyphema was the most common complication, affecting 33%, and resolved spontaneously in all cases. No vision threatening complications occurred. CONCLUSION: GATT is a safe and effective procedure in eyes with PCG and clear cornea, including eyes that had previous failed glaucoma surgery. Circumferential GATT is associated with more favorable outcomes, while eyes with a larger CDR are at a higher risk for failure.