[A case of supranuclear hypoglossal nerve palsy with Avellis' syndrome due to a medullary infarction].

We reported a 72-year-old man with left supranuclear hypoglossal nerve palsy and right Avellis' syndrome due to a medullary small infarction. On admission, he showed slight disturbance of consciousness, ocular lateropulsion to the right side, rotatory nystagmus, dysarthria, absent right gag reflex, curtain sign, absent right palatal reflex, deviation of the uvula toward the left side, raise of only the left palate when the patient attempted to utter, paralysis of the right vocal cord and deviation of the tongue toward the left side. Neither atrophy nor fasciculation was observed on the tongue. 124 days after the onset, he had only the left supranuclear hypoglossal nerve palsy and right Avellis' syndrome. MRI showed a small lesion in the medulla, so lateral area of the medulla and a part of the reticular formation medial to the nucleus ambiguous presumed to be involved. These findings suggest that supranuclear pathway to the hypoglossal nucleus of the opposite side exists in the reticular formation near nucleus ambiguous.