Abstract
Purpose: :
To assess the outcome and efficacy of Ahmed Glaucoma Valve (AGV) implantation to control intraocular pressure (IOP) in patients with uveitis.
Methods: :
A retrospective chart review was performed of all patients with uveitis undergoing Ahmed glaucoma implant surgery from 1/2004-5/2008 by two glaucoma specialists with follow-up data included through 11/2010. Patients with any infectious or non-infectious uveitis with resultant uveitic, steroid-induced, or combined-mechanism glaucoma requiring an AGV for adequate IOP control were included. Those who required the use of an intravitreal corticosteroid implant were excluded. The primary outcome was time to failure or revision of the AGV. Failure was defined as having an IOP <6 or >21mmHg with or without medication use at 3 consecutive visits, the need for subsequent glaucoma surgery, or the loss of light perception. Secondary outcomes were mean IOP and number of glaucoma medications used at 1 and 2 years. Kaplan-Meier survival analysis was used to estimate the rate of failure after AGV implantation. A paired t-test was used to assess the significance of reduction of IOP and medication use at 1 and 2 years.
Results: :
There were 60 eyes of 53 patients meeting the inclusion criteria. The mean follow-up time was 28.1 ± 18.5 months (range: 0.5-68.3 months). Seven eyes required revision of their AGV at a mean postoperative time of 19.4 ± 20.4 months (range 0.5-50.8 months). An additional 8 eyes failed after a mean period of 28.8 ± 19.9 months (range 7.8-60.5 months). The estimated survival probability determined by Kaplan-Meier survival analysis was 0.88 (95% confidence interval: 0.79-0.98) at 1 year and 0.83 (95% confidence interval: 0.70-0.96) at 2 and 3 years. A statistically significant decrease in mean IOP from baseline (34.6 ± 9.9 mmHg) was observed at both 1 year (15.6 ± 7.0 mmHg, p=0.0001) and 2 years (14.6 ± 5.2 mmHg, p=0.0001) follow-up. A statistically significant reduction in the mean number of glaucoma medications was also seen from baseline (3.5 ± 0.9) at 1 year (1.5 ±1.4 medications, p=0.0001) and 2 years (1.6 ± 1.3 medications, p=0.0001) follow-up. Complications included hypotony, choroidal detachment and hemorrhage, fibrosis, and valve occlusion in 12 patients. There was no significant decline in vision.
Conclusions: :
Implantation of an AGV in patients with uveitis is effective in controlling IOP and reducing glaucoma medication usage in most patients through at least 2 years after surgery.
Keywords: clinical (human) or epidemiologic studies: outcomes/complications • uvea • wound healing