[Bilateral abducens nerve palsy followed by pseudoathetosis due to pontine hemorrhage--clinical and neuroradiological study].

Reported here are two cases with pontine hemorrhage presented with bilateral abducens nerve palsy and followed by pseudoathetosis, ataxia, and hemiparesis on the contralateral side of the lesion. The first case, a 57-year-old man, who suffered from bilateral abducens nerve palsy, deafness and hypoesthesia, ataxia, and hemiparesis of the right side of the body. MRI showed the confined lesion in the left side of tegmentum at the level of middle pons. When the abducens nerve palsy began to improve, pseudoathetosis of the right fingers appeared. About six months later, symptoms almost recovered, except for ataxia. The second case, a 48-year-old man who suffered from bilateral abducens nerve palsy, deafness of the left ear, and ataxia, hypoesthesia, and hemiparesis of the left side of the body was admitted. MRI disclosed a small lesion on the right side of the tegmentum at the level of middle pons. When the bilateral abducens nerve palsy was beginning to improve, pseudoathetosis of the left hand appeared. Three months later, pseudoathetosis of the left hand disappeared. Both patients presented here had a similar lesion in the tegmentum at the level of middle pons on the side contralateral to the side in which the pseudoathetosis was seen. Considering the clinical symptoms and radiological findings of these cases, it appears that a lesion which causes such rare neurological symptoms may involve the medial lemniscus, spinothalamic tract, lateral lemniscus, spinocerebellar fiber, and central tegmental tract at the tegmentum of the middle pons on the side contralateral to the cerebellar signs and pseudoathetosis.