Moyamoya disease and Down syndrome: case report and review of the literature.

We present the case of a 29-year-old woman with Down syndrome who developed bilateral frontal ischemic stroke. Cerebral angiography demonstrated an occlusion of the both supraclinoid internal carotid arteries associated with dilated collateral vessels, consistent with moyamoya disease. We review the clinical and radiological features of moyamoya disease associated with Down syndrome and discuss a few major physiopathologic hypotheses to explain this association.