Ocular neuromyotonia after gamma knife stereotactic radiation therapy.

Three patients who underwent multiple intracranial operations for recurrent nonsecreting pituitary adenomas followed by gamma knife stereotactic radiosurgery developed diplopia at 1, 5, and 6 years after the treatments. Examination disclosed features of ocular neuromyotonia, a phenomenon attributed to radiation damage to ocular motor cranial nerves. Amply reported after external beam radiotherapy, neuromyotonia has not been described after radiosurgery previously. These patients are, however, exceptional in that all had undergone multiple sellar region operations or received high doses of radiotherapy, or both.