• The optic nerves of 34 eyes of 34 patients with low-tension glaucoma were compared with those of 41 eyes of 41 patients with high-tension glaucoma. Mean intraocular pressure in the low-tension group was 16.9 ± 0.7 mm Hg (mean ± SEM) compared with 31.7 ± 0.8 mm Hg in the high-tension group. Mean total visual field loss was not significantly different in the two groups, as determined by computerized threshold perimetry (OCTOPUS). The optic disc rim in low-tension eyes was significantly thinner than in high-tension eyes (P =.018); the largest difference occurred inferiorly and infero-temporally (P <.001). The appearance of the optic nerve is useful to distinguish between these two subtypes of glaucoma and may be a more meaningful indicator than intraocular pressure. Our findings support the hypothesis that there are at least two different mechanisms for optic nerve damage in glaucoma.
Caprioli J, Spaeth GL. Comparison of the Optic Nerve Head in High- and Low-Tension Glaucoma. Arch Ophthalmol. 1985;103(8):1145-1149. doi:10.1001/archopht.1985.01050080057020