Abstract
Purpose: :
To determine whether intravitreal injections of anti-VEGF agents in patients with a prior trabeculectomy result in bleb failures/leaks and to assess whether a prior trabeculectomy alters the efficacy or frequency of intravitreal anti-VEGF agents in patients with CNV, RVO, and DME.
Methods: :
Included were patients who received intravitreal injections of anti-VEGF agents (ranibizumab or bevacizumab) in an eye that had previously had a trabeculectomy at a single academic center from January 1st, 2002 to January 1st, 2008. The primary outcome measure was the rate of trabeculectomy failure. Secondary outcome measures included the frequency of injections, changes in visual acuity, and complications from the intravitreal injections.
Results: :
Seven patients (4 male, 3 female, mean age 72 years [range 46-86]) met the inclusion criteria. Diagnoses included CNV secondary to age-related macular degeneration (4), CNV secondary to angioid streaks (1), and macular edema secondary to diabetes (1) and RVO (1). The mean time from trabeculectomy to intravitreal injection was 22.9 months (range 5-45 months). Mean follow-up of patients was 29.6 months (2-61 months).One of 7 eyes required a bleb revision 6 months following an intravitreal injection. The remaining eyes had a stable intraocular pressure during follow-up. A mean of 2.7 (range 1-5) intravitreal injections were required in the first 6 months after initial injection. Five of the 7 patients have not required further treatment, while 2 patients required 3 and 4 additional injections over a 9 and 26 month time period, respectively. None of the eyes developed endophthalmitis and a single eye developed a vitreous hemorrhage after intravitreal injection. Snellen visual acuity improved by 2 or more lines in 6/7 patients, and remained unchanged in 1 patient.
Conclusions: :
The use of intravitreal anti-VEGF injections in patients with prior trabeculectomies was effective in improving or stabilizing visual acuity of all patients in this series. The presence of a trabeculectomy site appears to increase the frequency of repeat injections, but further studies are needed to determine if anti-VEGF injections may increase the likelihood of a bleb-related complication.
Keywords: injection • outflow: trabecular meshwork • choroid: neovascularization