Long-Term Follow-up on Glaucoma Patients With Initial Single-Hemifield Defect: Progression Patterns and Associated Factors

Purpose: The purpose of this study was to investigate the clinical outcomes of primary open-angle glaucoma (POAG) with an initial single-hemifield defect on visual field (VF) testing and the related risk factors for the involvement of the opposite hemifield during follow-up. Methods: This longitudinal observational study included 108 POAG eyes of 108 patients who met the following conditions: (1) single-hemifield defect at initial VF examination; (2) follow-up >5 years. Eyes having undergone noncataract surgeries and laser treatment during the follow-up period were excluded. Patients were divided into group A (sparing of opposite hemifield) and group B (involvement of opposite hemifield) according to the patterns of VF progression. Baseline demographic and clinical characteristics were compared between the 2 groups. The Cox proportional hazards model was used to identify the risk factors for the involvement of the opposite hemifield. Results: A total of 63 eyes (58.3%) were classified as group A and 45 (41.7%) as group B. The average follow-up period was 7.9 years. Between the 2 groups, significant differences were found in the age (55.7 +/- 10.7 vs. 61.0 +/- 10.5 y, P=0.015) and presence of optic disc vertical tilt (54.0% vs. 28.9%, P=0.034). According to the multivariate Cox proportional hazards model, older age (hazard ratio=1.704; P=0.025) and absence of optic disc vertical tilt (hazard ratio=1.430; P=0.017) were risk factors for the involvement of the opposite hemifield. Conclusions: In 108 POAG eyes with an initial single-hemifield defect, 41.7% showed involvement of the opposite hemifield during the average 8.0-year follow-up. Older age and absence of optic disc vertical tilt were significantly associated with a greater probability of involvement of the opposite hemifield.