Safety And Efficacy Of Achieving Single-Digit Intraocular Pressure Targets With Filtration Surgery In Eyes With Progressive Normal-Tension Glaucoma

PURPOSE: Whereas achieving intraocular pressure (IOP) targets ≤10 mm Hg typically requires surgical intervention, we sought to examine the safety and efficacy of trabeculectomy in normal-tension glaucoma (NTG). METHODS: Patients with progressive NTG undergoing trabeculectomy with preoperative IOP ≤ 15 mm Hg during the 12-month period prior to surgery were identified at a single academic institution. Failure was defined as IOP reduction < 20% below baseline (criteria A), < 30% (criteria B), or < 40% (criteria C), reoperation for glaucoma, or loss of light perception vision. RESULTS: Thirty eyes of 28 patients (mean age 73 ± 8.7 years) were enrolled with a mean follow-up period of 50 ± 31 mos. Mean postoperative IOP (8.6 ± 2.9 mm Hg) and medications (0.6 ± 1.0) at final follow-up was significantly (p<0.001) reduced compared to prior to surgery (13.2 ± 1.4 mm Hg and 2.5 ± 1.2, respectively). The cumulative probability of failure during 5 years of follow-up was 32% (criteria A), 48%, (criteria B), and 67% (criteria C). The probability of successfully achieving an IOP goal ≤10 mm Hg was 68% at 4 years follow-up. CONCLUSIONS: Trabeculectomy is a safe and effective method for achieving single digit IOP targets in NTG eyes with progression at low IOP

Effectiveness of Single-Digit IOP Targets on Decreasing Global and Localized Visual Field Progression After Filtration Surgery in Eyes With Progressive Normal-Tension Glaucoma

To examine the effectiveness of achieving single-digit intraocular pressure (IOP) targets with filtration surgery on decreasing global and localized visual field (VF) progression in eyes with progressive normal-tension glaucoma (NTG). A retrospective chart review was conducted to identify NTG patients who underwent trabeculectomy with mitomycin C between 2006 and 2010 for progressive VF loss with preoperative IOP≤15 mm Hg during the 12 months before surgery. All eyes had glaucomatous optic neuropathy and progressive VF loss, uncontrolled IOP on maximum therapy, and a minimum of 2 baseline preoperative and 4 postoperative VF examinations. VF progression was assessed using Guided Progression Analysis (GPA) and Progressor software. Fifteen eyes of 14 patients (mean age 71.8±7.5 y) were enrolled with mean follow-up of 71±26 months. Mean postoperative IOP (8.5±3.5 mm Hg) was significantly (P<0.001) reduced compared with preoperatively (13.1±1.5 mm Hg). The probability of achieving an IOP goal ≤10 mm Hg was 66% at 4 years' follow-up. The overall rate of postoperative VF progression using any method was 13.3% (1 eye using Progressor; 1 eye using GPA and Progressor). Average postoperative slope of MD (-0.25±0.86 dB/y) and pattern SD (0.49±0.83 dB/y) were improved (P=0.05 and 0.07) compared with the preoperative slopes (-1.05±0.66 and 1.21±0.71 dB/y). Achieving single-digit IOP targets with filtration surgery has a beneficial effect on reducing global and localized rates of VF progression in NTG eyes with progression at low IOP