Gonioscopy-assisted transluminal trabeculotomy as an option after failed trabeculectomy

Purpose To evaluate the safety and efficacy profile of gonioscopy-assisted transluminal trabeculotomy (GATT) in patients with open-angle glaucoma with a history of previous failed trabeculectomy surgery. Method This case-series study included 26 eyes of 26 consecutive patients with a mean age of 64.1 +/- 4.5 (56-78) years who underwent GATT using the 5/0 prolene suture to treat medically uncontrolled moderate to advanced glaucoma despite the previous trabeculectomy surgery. At baseline and each visit, Snellen best-corrected visual acuity (BCVA), IOP values, cup-to-disc (C/D) ratio, retinal nerve-fiber layer thickness and mean deviation values in visual field test were recorded. Need for medication or further glaucoma surgery were noted. Surgical success was defined as final IOP <= 15 mmHg and >= 20% IOP reduction from baseline without any further glaucoma surgery. Results Twelve (46.2%) patients with primary open angle glaucoma (POAG) and fourteen (53.8%) patients with pseudoexfoliative glaucoma (PEXG) underwent GATT. Average baseline IOP was 25.3 +/- 5.4 (16-45) mmHg. Mean follow-up time was 17.8 +/- 4.1 (12-26) months. Mean baseline BCVA was 0.47 +/- 0.25. Surgical success was achieved in 16 of 26 (61.5%). In ten of patients, medically uncontrolled glaucoma persisted after GATT surgery and they underwent further glaucoma surgery. PEXG patients showed a higher IOP reduction than POAG patients did at last follow-up (45.6% vs 34.8%). Conclusion The present study revealed that GATT was an effective procedure as a second IOP-lowering surgery in PEXG patients having previous failed trabeculectomy. However, in POAG patients having previous failed trabeculectomy, GATT seems to have a limited efficacy.