To compare the results of Ahmed glaucoma valve (AGV) implantation in eyes containing silicone oil to those without silicone oil.
This was a multicenter, retrospective, comparative study of 94 eyes in 94 patients with mean follow-up of 2 years, comparing surgical outcomes in eyes with silicone oil (N=47) to matched patients without silicone oil (N=47). Success was defined as intraocular pressure (IOP) of ≥6 and ≤21 mm Hg and 20% reduction of IOP from preoperative level, with or without glaucoma medicines, and without further glaucoma surgery or loss of light perception.
The mean IOP and number of medications at the last follow-up were comparable between the 2 groups (P=0.26 and P=0.12). The cumulative probability of success by life-table analysis was 85% at 6 months, 80% at 1 year, 70% at 2 and 3 years, and 47% at 4 years in silicone oil group, and 100% at 6 months and 1 year, and 76% at 2, 3, and 4 years in the control group (P=0.03). Complications were similar in the 2 groups (P=0.663). The duration of postoperative topical steroid use was significantly longer in the silicone oil group (P=0.0003). Silicone oil was identified as a risk factor for surgical failure by the Cox hazard model (risk ratio=3.43; P=0.04).
The AGV can control the IOP in the majority of eyes after pars plana vitrectomy and silicone oil injection. However, the presence of silicone oil is associated with increased risk of surgical failure in eyes treated with the AGV.