Abstract
Purpose :
Patients with advanced glaucoma can need IOP’s below the normal range to prevent further glaucomatous progression. Trabeculectomy surgery with anti-fibrotic supplementation and glaucoma drainage device (GDD) surgery have been the common surgical methods to lower IOP when medication is insufficient. The TVT study1 suggested similar mean IOP’s in the low teen level with both techniques. However, for patients that require very low IOP’s (10 or less) it is unclear which surgical procedure is more likely to be successful.
Methods :
A retrospective, single-center review of 60 pseudophakic patients with a diagnosis of POAG, Pseudoexfoliation or Pigmentary glaucoma, undergoing either a GDD implant or a trabeculectomy with adjunctive antifibrosis therapy as an initial glaucoma procedure (n=28 for GDD and n=32 for trab). Patient demographics, preoperative and postoperative IOP's, visual acuities, ocular medications, complications, and need for additional surgeries were recorded.
Results :
Demographically, there was no significant difference between the groups for age, gender and diagnoses but there were more African Americans in the Tube group (39% versus 13%). Mean IOP's at 1, 3, and 4 years post-op were 13.1 (SD=5.4), 12.6 (SD=5.7), 13.5 (SD=6.4) mmHg, and 8.9 (SD=5.0), 7.3 (SD=3.6), 6.9 (SD=3.9) mmHg for the drainage implant and trabeculectomy groups respectively. The IOP’s were statistically different at all these time-points (p<0.05). The number of patients with a mean IOP 10 mmHg or less at 2 years was 5/19 (26.3%), for the GDD patients and 15/23 (65.2%), for trabeculectomy patients (p=0.028). At 3 years worsening of visual acuity (2 lines Snellen or more) occurred in 4/16 patients in the GDD group, with 4/16 improving 2 lines or more. 3/21 in the Trabeculectomy group worsened, with 2/21 improving. There were no significant differences between the two procedures for decrease of visual acuity at 1, 2, 3 or 4 years.
Conclusions :
Trabeculectomy gives lower mean IOP and is more likely to provide a pressure of 10 or less than GDD’s in pseudophakic primary glaucoma patients with no differences noted in visual acuity.
1. Gedde, S. J., Schiffman, J. C., Feuer, W. J., et al. (2012). Treatment outcomes in the Tube Versus Trabeculectomy (TVT) study after five years of follow-up. Am J Ophthalmology, 153(5), 789–803.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.