Ab interno trabeculectomy: outcomes in exfoliation versus primary open-angle glaucoma

Abstract

Purpose: To compare outcomes in exfoliation glaucoma versus primary open-angle glaucoma (POAG) after ab interno trabeculectomy alone (Trabectome) or in combination with cataract surgery and intraocular lens (IOL) implantation.

Setting: Trabectome Study Group institutions.

Design: Prospective nonrandomized cohort study.

Methods: Outcomes included intraocular pressure (IOP), glaucoma medications, complications, secondary procedures, and success, defined as no secondary surgery and IOP less than 21 mm Hg and a greater than 20% reduction from baseline.

Results: In the ab interno trabeculectomy-alone group, the mean preoperative IOP was 29.0 mm Hg ± 7.5 (SD) in exfoliation glaucoma cases and 25.5 ± 7.9 mm Hg in POAG cases (P<.01). At 1 year, the mean decrease in IOP was -12.3 ± 8.0 mm Hg and -7.5 ± 7.4 mm Hg, respectively (P<.01); the secondary procedure rate was 20.9% and 34.9%, respectively (P=.02); and the cumulative probability of success was 79.1% and 62.9%, respectively (P=.004). In the combined ab interno trabeculectomy-IOL group, the mean preoperative IOP was 21.7 ± 8.4 in exfoliation glaucoma cases and 19.9 ± 5.4 mm Hg in POAG cases (P=.06). At 1 year, the mean decrease in IOP was -7.2 ± 7.7 and -4.1 ± 4.6, respectively (P<.01); the secondary procedure rate was 6.7% and 6.1%, respectively (P=.88); and the cumulative probability of success was 86.7% and 91.0% (P=.73), respectively.

Conclusion: Ab interno trabeculectomy using this new incisional procedure safely lowered IOP to the mid teens, with an overall greater reduction in exfoliation glaucoma and improved success when combined with cataract surgery.