Dae Young Lee, Hoon Seok Jeong, Hae Jung Paik, Dong Heun Nam (Incheon, South Korea)

Purpose:

To compare the efficacy and safety of Ahmed glaucoma valve implantation through the anterior chamber versus through the pars plana.

Patients & Methods:

A retrospective review of the records of 35 eyes (32 patients) that underwent Ahmed Glaucoma Valve surgery from 2007 to 2010. 18 eyes had anterior chamber insertion (AI) versus 17 eyes with pars plana insertion (PI). Demographic, preoperative, and postoperative data including intraocular pressure (IOP), visual acuity, and number of medications, and complications were recorded. Success was defined as postoperative IOP between 5 and 21 mm Hg and at least a 20% reduction from baseline IOP.

Results:

Patients were followed for a mean period of 13.1+/-6.2 months and 12.8+/-5.7 months in the AI and PI group, respectively. Success rates were similar at last follow-up visit: 15 eyes (83.3%) versus 16 eyes (88.2%) for anterior chamber and pars plana implants, respectively. However, eyes in the anterior chamber group had a significantly higher mean IOP (13.3+/-4.5 vs. 17.5+/-5.9 mmHg, P < 0.05, t test) and more antiglaucoma medications (1.9+/-0.8 vs. 1.2+/-0.6 medications, P < 0.05, Mann-Whitney test) than eyes in the pars plana group. There were more complications in the anterior chamber group; however, they did not reach stastistical significance.

Conclusions:

Anterior chamber and pars plana implants have similar success rate. However, the Ahmed glaucoma valve through anterior chamber may be less effective at lowering IOP than the pars plana implant.