Measurement of thickness of retinal nerve fiber layer by scanning laser polarimetry and high-pass resolution perimetry in patients with primary open-angle or normal-tension glaucoma

Purpose: To evaluate the correlation between neural capacity, determined by high-pass resolution perimetry, and thickness of the retinal nerve fiber layer, evaluated by scanning laser polarimetry, in patients with primary open-angle glaucoma or normal-tension glaucoma. Methods: Thickness of the peripapillary retinal nerve fiber layer was measured by scanning laser polarimetry in 19 eyes of 19 patients with primary open-angle glaucoma and in 23 eyes of 23 patients with normal-tension glaucoma. There were no significant differences between the two groups in mean age, sex ratio, or mean neural capacity. Results: Neural capacity was significantly correlated with thickness of the retinal nerve fiber layer in all 42 eyes (r = 0.31, P = 0.0429). Neural capacity was significantly correlated with thickness of the retinal nerve fiber layer in the eyes of patients with primary open-angle glaucoma (r = 0.60, P = 0.0061), but not in the eyes of patients with normal-tension glaucoma (r = 0.04; P = 0.8522). Conclusion: The degree of correlation between neural capacity determined by high-pass resolution perimetry and thickness of the retinal nerve fiber layer measured by scanning laser polarimetry appeared to differ in patients with primary open-angle glaucoma vs those with normal-tension glaucoma.