[Gaze-evoked eyelid closure. Report of two cases].

Various types of associated movements of eyeballs with other cranial muscles have been described in the literature. Only a few observations, however, have been reported on the relation of ocular movements and facial muscles innervated by the facial nerve, especially the orbicularis oculi muscles. We report two cases presenting gaze-evoked involuntary contraction of the orbicularis oculi muscle and unilateral eyelid closure. Case 1 was a 38-year-old housewife who was admitted to our hospital because of gait disturbance and sensory deficits below the neck. She had a 5-year history of left facial palsy, disturbed horizontal eye movements, retrobulbar optic neuritis, spastic paraparesis and bladder and rectal disturbances, some of which had relapsed a few times. Neurological abnormalities were summarized as follows: bilateral pale discs, right Horner's sign, horizontal nystagmus, left facial nerve palsy of peripheral type, spastic paraparesis with left-sided predominance, sensory disturbances below the third cervical segment, truncal and limb ataxia, and bladder and rectal disturbances. Gaze-linked synchronized contraction of the left facial muscles was observed and on the left lateral gaze marked spasm of the left orbicularis oculi muscle with occasional lid closure was evoked. Case 2 was a 72-year-old female with cerebellar hemorrhage. Neurological abnormal findings included mild disorientation, meningeal irritation signs, horizontal nystagmus on lateral gaze, reduced response of reflex eye movement to the left, minimal weakness of the left facial muscles, ataxic dysarthria, mild left hemiparesis and hemisensory deficits with face, truncal and limb ataxia. She could move eyeballs to any direction but with effort to the left.(ABSTRACT TRUNCATED AT 250 WORDS)