1989 Volume 11 Issue 4 Pages 416-421
We have reported here a case of paramedian thalamic and midbrain infarct presenting bilateral oculomotor nerve palsy and unilateral asterixis. A 68-year-old man with a history of hypertension and WPW syndrome developed paroxysmal atrial flutter on January 11 1988. An electrical cardioversion was done and his electro-cardiogram returned to sinus rhythm. On the next day morning, he suddenly lost his consciousness after he left his bed and was admitted to our hospital. On examination abnormal neurological findings included bilateral oculomotor nerve palsy, right cerebellar ataxia, transient loss of consciousness and transient unilateral ataxia. As CT and MRI studieis revealed left thalamic and midbrain lesion, paramedian thalamic and midbrain infarct was suspected, which was caused by occlusion of paramedian branches of midbrain artery. Bilateral oculomotor nerve palsy due to cerebral infarction is rare and only 17 cases have so far accumulated in the literatures as far as we know. But in case of occlusion of paramedian mesencephalic artery bilateral oculomotor nerve palsy is supposed to occur more frequently than expected. In addition unilateral asterixis due to midbrain origin is also rare. In a reported case, occlusion of the paramedian mesencephalic artery was suggested by the brain CT image. Even in the literatures of unilateral asterixis caused by thalamic lesion, some authers suggested that midbrain lesion played an important role in the genesis of unilateral asterixis. On the basis of these reports plus CT and MRI findings of our patient, we supposed that occlusion of midbrain paramedian branches had potential participation in the occurrence of unilateral asterixis.
