Abstract
Purpose: :
To evaluate efficacy of a second glaucoma implant in eyes with inadequate IOP control following a primary implant.
Methods: :
Medical records of all patients undergoing a second glaucoma implant surgery from 1996 to 2008 were reviewed. Patient demographics, ocular findings, glaucoma medications, and surgical complications were recorded. Success was defined as IOP < 21mm Hg with at least 25% reduction in IOP and no prolonged hypotony (IOP <4mm Hg).
Results: :
We enrolled 46 eyes of 43 patients (mean age, 53±23 yrs). Previous surgeries included failed trabeculectomy (43 eyes), cataract surgery (40 eyes) and glaucoma implants in all eyes (Baerveldt, 23 eyes; Ahmed, 14 eyes; Molteno, 6 eyes; Schockett, 2 eyes and Krupin, 1 eye). Mean follow-up following second implant was 32±22 months. Life-table analysis demonstrated success rates of 91%, 87% and 82% at 1, 2 and 3 years, respectively. Mean IOPs (13.1±5.3 vs. 24.8±7.6mm Hg, p<0.001) and number of medications (1.5±1.3 vs. 4.0±1.3, p<0.001) were lower following the second implant. No major intraoperative complications occurred. There was no difference in preoperative and most recent LogMAR visual acuities (0.88 ± 0.14 vs. 1.0±0.15, p=0.08). The most frequently used second implants resulted in similar percentage IOP reduction from preoperative IOP before the second implant (Baerveldt: 46±20%; Ahmed: 40±18%, p=0.3). The most frequently used implant combinations were similar in percentage IOP reduction from IOP before any device implantation (Baerveldt-Ahmed: 55±14%; Ahmed-Baerveldt: 55±18%; Baerveldt-Baerveldt: 53±15%, p=0.9). There was no correlation between total surface area of both implants and percentage IOP reduction from baseline IOP prior to the first tube implant (p=0.3).
Conclusions: :
A second glaucoma implant may effectively lower IOP in eyes with refractory glaucoma.
Keywords: clinical (human) or epidemiologic studies: outcomes/complications • clinical (human) or epidemiologic studies: systems/equipment/techniques • clinical research methodology