Prolonged but reversible migraine-like episodes long after cranial irradiation.

The authors describe three patients with prolonged but reversible episodes of severe headaches and focal neurologic deficits developing years after irradiation for cranial neoplasms. Despite extensive evaluations, etiology of episodes in these three and eight other previously reported patients remains undetermined. Whether they all have the same condition is uncertain. Although some had cortical gadolinium enhancement on MRI, all 11 patients returned to baseline over hours to weeks.