We observed bilateral ocular neuromyotonia in a 45-year-old woman prev
iously treated for a pituitary adenoma. She experienced episodic diplo
pia attributable to dysfunction of muscles innervated by both oculomot
or nerves. Oculography demonstrated episodes of tonic adduction with s
lowing and restriction of saccades in all directions, but no oscillato
ry component. A combination of impaired phasic firing in agonist muscl
es and tonic contraction of antagonist muscles explains the paroxysms
of eye movement limitation in this disorder.