Ocular neuromyotonia: a case report

Ocular neuromyotonia is a rare clinical entity, which is characterized by spontaneous spasm of ocular muscles resulting in paroxysmal diplopia and strabismus. Inappropriate discharges from ocular motor neurons or axons with unstable cell membranes may cause the sustained contraction of their respective ocular muscles. In most cases, ocular neuromyotonia resulted from radiation therapy to the parasellar and sellar regions or compressive lesions on ocular motor nerves. Among 30 patients reported in the literatür only six patients were accepted as idiopathic. Here, we reported a patient with third nerve myotonia representing with spells of diplopia. No lesion was found and she was accepted as idiopathic ocular neuromyotonia.