Magnification corrected measurements of the neuroretinal rim area of the optic nerve head were correlated with semiquantitative scores of diffuse and localized loss of retinal nerve fibers. The study comprised 134 patients, including 33 normal control subjects, 50 patients with suspected glaucoma, and 51 patients with glaucoma. Both of these estimates of the amount of neural tissue in the eye were highly significantly correlated with the rim area, with the diffuse nerve fiber loss score having somewhat higher correlation coefficient than the localized nerve fiber loss score.