Intereye comparison of visual field progression in eyes with open-angle glaucoma

To investigate the intereye correlations between and differences in the rates of visual field (VF) progression in eyes with bilateral open-angle glaucoma.

Retrospective, longitudinal, observational study.

Patients with bilateral open-angle glaucoma with 8 or more reliable 30 - 2 standard automated perimetry tests over a period of more than 2 years were enrolled. The rate of change of the MD (MD slope) was used as the indicator for the rates of VF progression. Descriptive statistics of the absolute intereye difference in the MD slope values were computed. Factors associated with a large intereye difference (> 0.42 dB/year) were explored.

One hundred eighty-eight eyes from 94 patients (56 women) were enrolled. A significant intereye correlation of the rates of visual field progression (P = .002) was found. The mean ± standard deviation and median intereye differences of the MD slope values were 0.29 ± 0.31 and 0.18 dB/year (range: 0-1.41), respectively. The 5th, 10th, 25th, 75th, 90th, and 95th percentiles of intereye differences were 0.01, 0.02, 0.08, 0.42, 0.72, and 0.91 dB/year, respectively. Older age and slower progression were significantly associated with large intereye difference.

A significant intereye correlation in the rate of VF progression was found in eyes with bilateral open-angle glaucoma. We showed the distributions and associated factors of intereye differences in VF progression. These data may be used for improving the estimation of rates of VF progression.