Outcomes and bleb-related complications of trabeculectomy

Abstract

Purpose: To determine rates of success and complications of trabeculectomy surgery.

Design: Case series.

Participants: Consecutive patients undergoing trabeculectomy by 2 surgeons between May 2000 and October 2008.

Intervention: By using the Wilmer Institute's billing database, we identified all patients at least 12 years of age coded as having undergone trabeculectomy between May 2000 and October 2008 by 1 of 2 glaucoma surgeons and whose surgery was not combined with another operation. From the chart, we abstracted demographic information on the patients and clinical characteristics of the eyes. The Kaplan-Meier product-limit method and Cox proportional hazard models were used to look at success rates and characteristics associated with inadequate intraocular pressure (IOP) reduction. Complications were tabulated.

Main outcome measures: (1) Success rate of trabeculectomy, as determined by the achievement of each of 4 different IOP goals, with or without IOP-lowering medications; and (2) incidence of surgical complications.

Results: During the study period, 797 eyes of 634 persons underwent trabeculectomy without concurrent surgery. The success rates 4 years after surgery, with or without the use of IOP-lowering eye drops, were 70%, 72%, 60%, and 44%, for achievement of target IOP, ≤18 mmHg and ≥20% IOP reduction, ≤15 mmHg and ≥25% reduction, and ≤12 mmHg and ≥30% reduction, respectively. Increased chance of success was associated with European-derived race; use of mitomycin C (MMC); higher concentrations of MMC, when used; and higher preoperative IOP. Age and previous intraocular surgery were not associated with surgical success. Complications included worsening lens opacity in 242 of 443 phakic eyes (55%), loss of ≥3 lines of acuity (Snellen) in 161 eyes (21%), surgery for bleb-related problems in 70 eyes (8.8%), and infection occurring >6 weeks after surgery in 27 eyes (3.4%). A total of 101 eyes of 94 patients had at least 1 subsequent operation for inadequate IOP control.

Conclusions: Trabeculectomy surgery performed by 2 experienced glaucoma specialists achieved target IOP at 4 years in 70% of those operated and was associated with progressive cataract and small risks of bleb-related complications. These results are comparable to those reported in smaller series.