Short-Term Enhancement of Visual Field Sensitivity in Glaucomatous Eyes Following Surgical Intraocular Pressure Reduction

PURPOSE: To examine the hypothesis that surgical intraocular pressure (IOP) reduction leads to enhancement of visual field (VF) sensitivity in glaucomatous eyes. DESIGN: Prospective case-control study. METHODS: Patients with uncontrolled IOP requiring trabeculectomy or aqueous drainage device were enrolled. Controls consisted of medically treated glaucoma patients with stable IOP and no change in medical therapy during follow-up. Two baseline preoperative VFs and 3 follow-up VF examinations at 1, 2, and 3 months postoperatively were used for analysis. The same number of VF examinations measured within an 18-month interval was used for control eyes. VF locations with significant change were defined as exceeding 95% test-retest confidence limits based upon the mean sensitivity using the 2 baseline VF exams. The number of significantly changing locations per eye and changes in mean and pattern standard deviation (PSD) from the mean baseline fields were compared between groups using a Poisson generalized estimating equation model. RESULTS: Thirty eyes of 30 surgically treated glaucoma patients and 41 eyes of 28 stable controls were enrolled. Postoperative IOP was decreased at follow-up 3 compared with baseline (P < .001) in the surgical eyes, but was similar in control eyes (P = .92). At follow-up 3, the number of test locations improving in central (P = .014) and peripheral (P = .019) VF locations was significantly greater in the surgical eyes. The number of eyes with improved PSD at follow-up 3 was significantly greater in the surgical eyes compared with controls (P = .02). CONCLUSIONS: Short-term enhancement of central and peripheral VF sensitivity occurs after surgical reduction of IOP in glaucomatous eyes and may represent a potential biomarker for retinal ganglion cell response to therapeutic interventions in glaucoma. (C) 2015 by Elsevier Inc. All rights reserved.