**4. Evaluation of outcomes**

All patients underwent a detailed ophthalmic examination, including Humphrey visual field analysis and gonioscopy. Patient progress was reviewed at 1 and 3 days; 1 and 2 weeks; and 1, 2, 3, 4, 5, 6, 9, and 12 months after surgery, and intraocular pressure was studied. Intraocular pressure was measured with a Goldman applanation tonometer. Three measurements were recorded in each eye, the mean of which was used in the calculations, with an interval of 2 weeks before surgery at the same time (±1:00). Postoperatively, intraocular pressure was measured at the same time (±1:00) as at baseline. The optic nerve was examined with a Goldman three-mirror lens and measurements were taken of the size of the disk, the vertical and horizontal cup/disk ratios, the presence of rim notching or splinter hemorrhage, and the presence of peripapillary atrophy. Visual field testing with a Humphrey visual field analyzer (Humphrey-Zeiss, Dublin, CA, USA), Program 30-2 SITA STNADARD™ testing was carried out before surgery and at 6 and 12 months after surgery. Best-corrected visual acuity was measured at the 1-, 2-, 3-, 4-, 5-, 6-, 9-, and 12-month visits, and the logarithm of the minimum angle of resolution (logMAR) was calculated and used for all statistical analyses.

The presence of complications was determined intraoperatively and at every postoperative visit. Hypotony was defined as an intraocular pressure of less than 4 mm Hg after surgery. A shallow anterior chamber was defined as reported by Teehasaenee and Ritch [11]. An intra‐ ocular pressure spike was defined as an intraocular pressure on the first postoperative day of greater than or equal to 3 mm Hg higher than the preoperative level.

The surgery was considered as a success with an intraocular pressure between 6 and 20 mm Hg and an intraocular pressure reduction of greater than or equal to 30% without additional surgery, compared to the preoperative level with medical therapy. A failure was defined when an eye required further glaucoma surgery or lost visual function.

In case of postoperative intraocular pressure measurements of greater than 21 mm Hg in the trabculectomy group, despite all procedures including laser suture lysis, 5-fluorouracil injection, and needling, intraocular pressure-lowering medication was added. In case of complications requiring surgery or still inadequate intraocular pressure control in both groups, additional procedures could be performed as required.

**Study End.** All patients were meant to reach a 12-month follow-up, but the following were considered as endpoints: (1) the need for any further surgical procedure (except laser suture lysis, 5-fluorouracil injection, and needling); (2) an intraocular pressure of greater than 21 mm Hg on two consecutive visits; and (3) patient failure to attend scheduled visits, allowing for a margin of tolerance. If the study was ended before month 12, the last values obtained in the trial were considered as the final data.
