Detection of glaucomatous nerve fiber damage. Laser polarimetry in comparison with equivalent visual field loss

Abstract

A total of 45 eyes of 45 patients were equally divided into three age-matched groups (controls, glaucoma, suspected glaucoma). All patients were examined using laser polarimetry and automated visual field testing. We compared the agreement of the location of visual field defects with changes in the nerve fiber layer. In addition we calculated the change in NFLT along a peripapillary circle at four different distances of the optic disc margin. The localization of nerve fiber defects corresponds to the localization of the visual field defect exactly in eight of 15 eyes and roughly in another five. Six of the eyes suspected of having glaucoma showed pathological results with the nerve fiber analyzer (NFA) although visual fields were normal. There was a significant difference for NFLT change towards the periphery between the three groups. While the NFA does not always allow a definite correlation between morphological defects and resulting functional impairment, a decrease in the NFLT with increasing distance from the optic disc margin seems helpful for clinical classification. The value of this new method has yet to be proven in longitudinal clinical studies.