Moyamoya syndrome with unusual angiographic findings and protein C deficiency: review of the literature.

We describe the findings in a six-year-old female with typical clinical symptoms of Moyamoya phenomena, but with an unusual angiographic appearance. The vertebral artery showed segmented occlusion in the upper cervical region, with reconstitution via collateral circulation through muscular branches. The carotid circulation showed involvement of the external carotid artery (ECA) branches and marked narrowing of the internal carotid arteries (ICA) bilaterally, suggesting that this disease is systemic in nature.