Optic disc findings in normal tension glaucoma.

One hundred thirty stereo photographs of optic discs in patients with normal tension glaucoma (NTG) were reviewed in order to identify characteristics of the three following types of NTG: focal ischemic, senile sclerotic, and generalized cup enlargement. Twenty patients in each group were selected. Focal ischemic patients were more frequently women, had a higher incidence of migraine, a relatively smaller disc size, and localized superior scotoma that often threatened fixation. Senile sclerotic patients were generally elderly, had a higher incidence of surgery under general anesthesia, had more ischemic heart disease or systemic hypertension, had a small rim area, and also had extensive peripapillary atrophy as well as combined diffuse and localized visual field defects. Generalized cup enlargement patients were younger, had a relatively larger disc size and a greater incidence of purely diffuse visual field loss. Results of our study suggest that the different characteristics of the groups are related to pathogenic mechanisms specific to each group.