Abstract
Purpose: :
To compare the efficacy and safety of the Baerveldt–250mm2 Glaucoma Implant and the Ahmed S2 Glaucoma Valve in the treatment of adult glaucoma.
Methods: :
Retrospective, comparative, interventional case series consisting of 169 patients who received either the Baerveldt–250mm2 Glaucoma Implant (111 eyes of 111 patients) or the Ahmed S2 Glaucoma Valve (58 eyes of 58 patients) by the IU Glaucoma Service from 1996 to 2002. Eyes that had previous drainage implant procedures were excluded from both groups. If both eyes of a single patient received an implant, the second eye to undergo implantation was excluded from the study. Main outcome measures included intraocular pressure (IOP), visual acuity, number of glaucoma medications, and surgical complications. Success was defined as IOP > 5 mmHg and < 22 mmHg (with or without anti–glaucoma medications), and without further glaucoma surgery, devastating complication (i.e. suprachoroidal hemorrhage, retinal detachment), or loss of light perception attributable to drainage implantation.
Results: :
The two groups were similar with regards to age, gender, race, NVG diagnosis, number of prior ocular surgeries, preoperative IOP, and number of preoperative glaucoma medications. Mean duration of follow–up was 22.4 months for Baerveldt eyes and 19.2 months for Ahmed eyes. At last follow–up visit, eyes in the Baerveldt group had significantly lower mean IOP (15.8 ± 7.5 vs. 19.8 ± 9.6 mmHg, p=0.004, t test) and fewer anti–glaucoma medications (0.8 ± 1.0 vs. 1.4 ± 1.2 medications, p=0.003, Mann–Whitney) than eyes in the Ahmed group. Although Kaplan–Meier survival was slightly better for Baerveldt eyes, the difference was not statistically significant. For all eyes, preoperative IOP was a significant predictor of eventual failure (HR: 1.03 per mmHg, p=0.004, Cox Proportional Hazard).
Conclusions: :
The Baerveldt–250mm2 Glaucoma Implant and the Ahmed S2 Glaucoma Valve are effective drainage implant options that may be used in the treatment of adult refractory glaucoma. Both devices control IOP and exhibit similar surgical outcomes. Our study suggests that the Baerveldt–250mm2 device may be more effective at lowering intraocular pressure. Regardless of the device used, preoperative IOP is a risk factor for eventual failure.
Keywords: intraocular pressure • clinical (human) or epidemiologic studies: outcomes/complications