Migrainous optic neuropathy.

Two patients with histories of classic migraine developed ischemic optic neuropathy during a severe headache. Clinical and radiologic studies excluded other causes for the visual field loss. In both cases, the field loss was permanent. No further visual or neurologic disturbances have occurred in either patient during a 3 1/2- and 2 1/2-year period of follow-up, respectively.