Bent ab interno needle goniotomy versus gonioscopy-assisted transluminal trabeculotomy in primary open angle glaucoma: a randomised clinical trial, 24-month outcomes

BACKGROUND: To evaluate and compare 24-month outcomes of Bent Ab interno Needle Goniotomy (BANG) and Gonioscopy-Assisted Transluminal Trabeculotomy (GATT) in pseudophakic primary open angle glaucoma (POAG) patients. METHODS: Parallel, double-arm, 1:1 ratio, single masked, randomised clinical trial. Pseudophakic POAG eyes with mild to moderate glaucoma and intraocular pressure (IOP) ≥ 18 mmHg under a maximum of 3 antiglaucoma medications were randomised to BANG or GATT. Main outcomes were mean IOP reduction from baseline and surgical success at 24-months. Complete surgical success was defined as IOP ≤ 18 mmHg and 20% IOP reduction from baseline under no medication. Qualified success followed the same parameters, but allowed the use of medication. Additional glaucoma surgery, clinical hypotony or loss of light perception were considered failures. RESULTS: A total of 45 eyes (22 BANG and 23 GATT) were included. At endpoint, in the BANG and GATT groups, mean IOPs were reduced by 16.0% (p < 0.01) and 22.44% (p < 0.01) (time-group analysis: p = 0.048), whereas medication was reduced by 6.22% (p = 0.89) and 69.78% (p < 0.01) (time-group analysis: p < 0.01), respectively. GATT eyes presented a higher number of medication-free eyes (11 vs. 2, p < 0.01) and IOPs in the low-teens (4 vs. 0, p = 0.02). GATT eyes achieved higher rates of complete (55.0% vs. 4.5%, p < 0.01) and qualified success (64.7% vs. 11.4%, p < 0.01). Additional surgery was needed in 3 (13.63%) BANG eyes and 4 (18.18%) GATT eyes (p = 1.0). CONCLUSION: GATT eyes achieved higher success rates, lower mean IOPs and required less antiglaucoma medication than BANG eyes after 24-months. Both techniques showed a good safety profile and low need for additional surgery.