Outcomes of Gonioscopy - Assisted Transluminal Trabeculotomy in Eyes with prior failed Glaucoma Surgery

Abstract

Purpose: To report outcomes of Gonioscopy - assisted Transluminal Trabeculotomy(GATT) in eyes with prior failed glaucoma surgery. Patients and Methods: A retrospective study involving 30 eyes of 30 patients, all of whom had open angles on gonioscopy, experienced prior glaucoma surgery failures, and subsequently underwent GATT. The primary outcome measure was success defined as complete when the intraocular pressure (IOP) was >5 and ≤21/16 mmHg without glaucoma medications and qualified with medications. Results: The mean age was 51.8±16.1 years. Twenty-one eyes underwent GATT and 9-eyes underwent Phaco-GATT. Twenty-seven eyes had failed trabeculectomy and 3 eyes had failed glaucoma drainage device. Post GATT, the IOP decreased from 27.1±7 to 16.9±6 mmHg (P<0.001) at the end of 15 months, with a mean drop in AGM from 4.9±1.0 to 2±1.6. At postoperative 1-year, the probability of complete success was 20%(95% CI: 9, 43] for an IOP criterion of both 21 and 16 mmHg. The qualified success probability at 1-year was 82%(67,100) for an IOP criterion of 21 mmHg and 57%(38, 84) for an IOP criterion of 16 mmHg. Risk factor for failure was older age (hazard ratio (HR) 1.03, 95% CI;1.01,1.06). The complications noted were hyphema in 14 eyes(46%), majority resolved within one week and all by 2 weeks. None needed any intervention. Conclusions: This study concludes that GATT can be an effective and safe surgical alternative for managing IOP in eyes with prior failed glaucoma surgeries, associated with minimal complications.