[Reasons for postoperative deterioration of visual fields in cases of advanced primary open-angle glaucoma (author's transl)].

In 86 patients suffering from advanced glaucomatous field defects visual functions were evaluated up to 12 years postoperatively. There was a 50% deterioration in visual acuity in 29 eyes (34%). This was mainly caused by new cataract formation. Visual fields were examined on the Tübingen perimeter. In 12 out of 80 eyes there was suspected deterioration and in another 28 eyes (35%) confirmed deterioration. In no case did surgery cause the preoperative field to disintegrate. The deterioration, which usually accelerates slowly, is a consequence of general vascular diseases such as diabetes mellitus, arteriosclerosis or hypertonia.