[Low tension glaucoma. Contribution to etiology (author's transl)].

A report on a patient with pathological cupping of the disc and visual field defects similar to those found in glaucoma. In the sitting position the IOP was 18 and 21 mm Hg and in lying over 30 mm Hg. This abnormal positional effect was measured with the pneumotonograph which is based on a new principle of applanation independent of position. The classification of glaucoma simplex and low tension glaucoma as well as the differentiation from pseudoglaucoma are discussed.