Initial intraocular pressure (IOP) reduction following Gonioscopy-assisted transluminal trabeculectomy (GATT) is greater in patients with pseudoexfoliative glaucoma (PXG) than in those with primary open-angle glaucoma (POAG), but this difference is eliminated over the course of the following year with the goal of contrasting the effects of GATT on the eyes to POAG and PXG with a unicentric, retrospective, and comparative case series. There were a total of 202 eyes (91 POAG and 111 PXG). GATT was done either independently or in tandem with cataract surgery. Success (defined as an IOP less than 20% from baseline or IOP between 6 and 21 mmHg, without future glaucoma surgery) and complications were measured at 1, 3, 6, 9, 12, 18, 24, and 36 months following surgery. Kaplan-Meier survival analyses were used to compare the chances of surviving over time. Patients in the POAG group reduced their glaucoma medication use by a median of 2 pills per day, resulting in a mean IOP reduction of 8.8 mmHg (34.4%). The average intraocular pressure (IOP) in the PXG group was reduced by 12.8 mm Hg (44.60%) while taking 2.3 fewer medicines. The mean IOP improvement was greater in PXG than in POAG until the 2-year visit (P<0.05 for all), but the difference was no longer statistically significant. The cumulative likelihood of success was substantially higher in PXG (97.6%) than in POAG (86.8%) after the 1st year (P=0.01), but after the 2nd and 3rd years (P=0.07 and P=0.24), there was no significant difference. Patients with POAG and PXG who underwent GATT reported decreased IOP and a lighter drug load. PXG had a much higher success rate than POAG in the first year after GATT, but both had success rates of around ~75% in the following years.