Impaired cognitive function due to cerebellar infarction and improvement after stent-assisted angioplasty for intracranial vertebral artery stenosis--case report.

A 69-year-old female presented with multiple cerebellar infarctions and mild cognitive dysfunction. Cerebral angiography revealed severe right vertebral artery (VA) stenosis just proximal to the origin of the posterior inferior cerebellar artery. Neuropsychology tests showed the mini-mental state examination (MMSE) score was 21, and the Wechsler Adult Intelligence Scale-Revised (WAIS-R) score was 70. Cerebrovascular reactivity (CVR) was decreased in the bilateral cerebral and cerebellar hemispheres. Stent-assisted angioplasty of the right VA was performed to prevent recurrence of the cerebellar infarction. Post-procedure, the neuropsychology tests showed cognitive improvement to MMSE score of 26 and WAIS-R score of 84. CVR had also improved in the bilateral cerebral hemispheres. Cerebellar hypoperfusion due to VA stenosis had probably caused functional depression of the cerebello-cerebral pathway, a condition referred to as crossed cerebello-cerebral diaschisis. In this case, cognitive dysfunction was reversed due to recovery of the cerebello-cerebral pathway.