Sequential Glaucoma Implants in Refractory Glaucoma

PurposeTo evaluate the efficacy of a second glaucoma implant in eyes with prior glaucoma implant surgery and inadequate intraocular pressure (IOP) control.DesignRetrospective observational cohort study.MethodsPatients undergoing a second glaucoma implant surgery from 1996 to 2008 were included. Outcome measures included visual acuity, IOP, glaucoma medication use, and complications. Success was defined as IOP < 21 mm Hg (criterion 1) and IOP < 17 mm Hg (criterion 2), with at least 25% reduction in IOP and no prolonged hypotony.ResultsForty-three eyes (43 patients) had a mean follow-up of 32.6 ± 21.6 months. Life-table analysis demonstrated success rates of 93%, 89%, and 83% using criterion 1 and 83%, 75%, and 75% using criterion 2 at 1, 2, and 3 years, respectively. At last follow-up, mean IOP (13.6 ± 4.6 vs 24.7 ± 7.5 mm Hg; P < .001) and mean number of medications (1.4 ± 1.2 vs 3.9 ± 1.2; P < .001) were lower following the second implant. There was no difference in preoperative and most recent logarithm of the minimal angle of resolution (logMAR) visual acuities (0.86 ± 0.13 vs 1.1 ± 0.13; P = .07). The most frequently used second implants were similar in percentage IOP reduction (Baerveldt implant, 45 ± 19%; Ahmed valve, 40 ± 18%; P = .4).ConclusionsA second glaucoma implant may effectively lower IOP in eyes with refractory glaucoma.