Primary Tube or Trabeculectomy for Glaucoma: 1-Year Outcomes
Ophthalmology, May 2018
Gedde et al. reviewed 1-year treatment outcomes of the primary tube versus trabeculectomy (PTVT) study and found that trabeculectomy plus mitomycin C (MMC) achieved greater success than did tube-shunt surgery.
This multicenter randomized study included 242 patients (242 eyes) with medically uncontrolled glaucoma and no previous incisional ocular surgery. Patients were enrolled at 1 of 16 centers and were assigned randomly to receive a tube shunt (350-mm2 Baerveldt glaucoma implant; n = 125) or trabeculectomy and MMC (0.4 mg/mL for 2 minutes; n = 117). Outcome measures were intraocular pressure (IOP), number of glaucoma medications, visual acuity, visual field findings, surgical complications, and treatment failure. Failure was defined as any of the following: IOP > 21 mm Hg or reduced by 20% or less from baseline on 2 consecutive follow-up visits after 3 months, IOP ≤ 5 mm Hg on 2 consecutive follow-up visits after 3 months, reoperation for glaucoma, or loss of light-perception vision.
The cumulative probability of failure in the year of follow-up was 17.3% for the tube group and 7.9% for the trabeculectomy group. At 1 year, the mean (± standard deviation [SD]) IOP was 13.8 (4.1) mm Hg for those with a tube shunt and 12.4 (4.4) mm Hg for those with trabeculectomy. The number of glaucoma medications (± SD) at 1 year was 2.1 (1.4) in the tube group and 0.9 (1.4) in the trabeculectomy group.
Postoperative complications occurred in 29% of tube recipients and 41% of trabeculectomy cases. Serious complications resulting in reoperation or a loss of at least 2 Snellen lines occurred in 1 patient (< 1%) in the tube group and 8 (7%) in the trabeculectomy group.
In general, the minimally invasive glaucoma procedures introduced in recent years have been less effective than tubes or trabeculectomy for lowering IOP. The authors stressed that selecting a suitable glaucoma operation involves considering risk/benefit profiles on a case-by-case basis, and they noted that they plan to report 3- and 5-year outcomes of the PTVT study.
The original article can be found here.