[Locked-in syndrome due to bilateral cerebral peduncular infarctions with occlusion of persistent primitive trigeminal artery].

A 61-year-old woman with diabetes mellitus was admitted to our hospital with right hemiparesis and dysarthria. Brain MRI showed bilateral cerebral peduncular infarctions. Three days after admission, she was unable to generate any voluntary movements, except for those of the eye, suggesting locked-in syndrome (LIS). She could not speak, but showed good comprehension by blinking in response to verbal commands. Brain CT 5 days later revealed subarachnoid hemorrhage (SAH) around quadrigeminal and ambient cistern. Cerebral angiogram on the following day revealed no aneurysm, occlusion of right persistent primitive trigeminal artery (PPTA) and a little flow of the bilateral vertebral arteries. Eye movements were impossible in all directions on the 11th day and MRI showed new infarctions of the midbrain and the ventral portion of the pons. However, an EEG on the 20th day was almost normal. We speculated that low blood flow in the basilar artery from the PPTA caused bilateral cerebral peduncular infarctions, and that weakness of the PPTA caused SAH.