Abstract
Purpose: :
To evaluate the efficacy of revision of the Ahmed Glaucoma Valve (AGV) in reducing intraocular pressure (IOP) in patients with uncontrolled glaucoma after implantation of this device.
Methods: :
This is a retrospective, non-comparative, interventional clinical case series. Medical records were reviewed of a consecutive series of 18 eyes of 18 patients who required additional surgical intervention for control of IOP following previous implantation of the AGV (model S-2 or FP-7). The need for AGV revision was based upon the treating physician’s clinical impression that IOP control was inadequate in spite of maximum tolerated medical therapy. A conjunctival incision was made over the anterior edge of the plate of the AGV, and removal of the fibrous capsule over the plate was performed. The tissue overlying the plate was treated with mitomycin-C 0.5 mg/ml for 5 minutes. The conjunctival incision was closed with a running polyglactin suture. Surgical success was defined by IOP between 6 to 21mmHg with or without glaucoma medication without reoperation or loss of light perception.
Results: :
The mean preoperative IOP was 30.2 mmHg. The mean patient age was 57.9 years (range: 6 to 89 years). The mean period between implantation and revision of the AGV was 13.9 months. The mean follow-up after AGV revision was 13.0 months (range: 3 to 48 months). A significant reduction in IOP following surgery was seen 6 months (19.8mmHg, p=0.001) and 1 year (15.3 mmHg, p=0.0001) following revision. Surgical success was observed at final follow-up in 50% of eyes.
Conclusions: :
Surgical revision of the AGV with removal of the fibrous capsule overlying the plate can result in significant improvement of IOP in many patients. This procedure may be considered as a reasonable alternative to insertion of a second AGV when recurrent IOP occurs following placement of an initial implant.
Keywords: intraocular pressure • anterior segment • wound healing