Correlation of visual field progression between eyes in patients with open-angle glaucoma

Abstract

Purpose To investigate the correlation of visual field progression between eyes in patients with chronic forms of open-angle glaucoma (OAG) and to determine risk factors for progression. Design Retrospective observational case series. Participants One hundred fifty-two patients seen between April and November 2000 undergoing bilateral treatment for at least 2 years for OAG and who were followed with standard automated perimetry at the University of Washington Medical Center Eye Clinic. Methods Visual field progression was defined using criteria modified from Anderson and Advanced Glaucoma Intervention Study (AGIS) scoring. Progression from a normal to an abnormal visual field required abnormality of two of three criteria (glaucoma hemifield test, corrected pattern standard deviation, and total deviation plot abnormality) on at least two consecutive fields. For abnormal visual fields, criteria for progression were modified from Anderson and were based on worsening observed at three adjacent points on the total deviation plot on at least two consecutive fields. Another definition of progression was a change in AGIS score of four or more points. Main outcome measures Visual field progression. Results The mean follow-up period was 7.5 ± 3.6 years. Fifty-four patients (35.5%) showed progression of the more severely affected of the two eyes (worse eye), and 37 patients (24.3%) had progression in the less affected fellow (better) eye. Among these patients, 24 (15.8%) had bilateral progression (44% and 65% of worse and better eyes with progression, respectively). The between-eye correlation for progression was statistically significant (chi-square with Yates’ continuity correction; χ = 16.7, P = 0.00004; R = 0.348, P = 0.00001). The Kaplan-Meier estimates at 10 years for progression in the worse eye, the better eye, and both eyes was 44%, 33%, and 21%, respectively. Conclusions Between-eye correlation of visual field progression in patients with chronic OAG was statistically and clinically significant. Patient-specific factors may play an important role in visual field progression in OAG. Documented progression of visual field loss in one eye may prompt the physician to consider reducing the target intraocular pressure in both eyes.