The size of the neuroretinal rim area of the disk was measured with the Optic Nerve Head Analyzer in 57 eyes of 57 patients with low-tension glaucoma (LTG), glaucoma simplex (POAG), and pigmentary glaucoma. The visual fields were examined with Program 33 or 31 (30 degrees eccentricity, 6 degrees grid) of the Octopus 201 Perimeter. The mean sensitivity loss per test point in the central field, in the field quadrants, and in the ranges from 0 degrees-10 degrees, 10 degrees-20 degrees, and 20 degrees-30 degrees were calculated with the Delta program. In addition, the mean loss per disturbed point, which gives the mean depth of scotomata, was calculated. In LTG a larger vertical cup/disk ratio (CDR) was found than in POAG for the same amount of total loss. The comparison of eyes with neuroretinal rim areas of equal size revealed that in contrast to POAG and pigmentary glaucoma, eyes with LTG had a smaller mean sensitivity loss; deeper, more localized scotomata; more visual field defects in the lower field in the initial stages; more scotomata in the area up to 20 degrees. The differences between glaucoma with and without high intraocular pressure were found to be most pronounced in the initial stages of the disease. These differences appear to be caused by the varying amounts of vascular pathogenesis involved. Therefore, at least two pathomechanisms have to be considered in glaucoma.