Rate of visual field loss in progressive glaucoma

Abstract

Objective: To investigate the rate of visual field (VF) loss in progressive glaucoma.

Setting: Outpatient department, nonreferral base.

Methods: A cohort of 34 patients with normal-pressure glaucoma (NPG), 68 patients with primary open-angle glaucoma (POAG), and 125 patients with ocular hypertension (OHT) were followed up for an average of 9 years. Visual fields were obtained annually with automated perimetry. The rate of VF loss as a percentage per year was calculated.

Results: Twenty-three eyes with NPG, 31 with POAG, and 10 with OHT showed progression of VF loss. The mean (+/-SD) rates of VF deterioration were 3.7%+/-3.3% per year in NPG, 2.5%+/-1.8% in POAG, and 2.3%+/-1.3% in OHT converting to POAG, and did not differ significantly. No difference in the rate of VF loss was found between eyes with and without optic disc hemorrhages (2.7%+/-2.9% and 3.1%+/-2.1%, respectively). The rate of VF loss was not related to the initial VF status. The rate of VF loss between the superior and inferior hemifields was correlated in patients with NPG (r(s) = 0.67, P = .04). Comparison of visual field loss with linear regression analysis showed significant slopes in only 37.5% of eyes with progression, which had a progression rate of 4.2%+/-3.0%.

Conclusions: The rate of VF loss did not differ between patients with NPG and POAG. The rate of deterioration was related neither to initial VF status nor to the presence of disc hemorrhages. Linear regression is applicable only in a portion of the patients who have progression of VF loss.