Moyamoya disease with occlusion of bilateral vertebral arteries and the basilar artery fed by the collateral vessels of vertebral arteries: A rare case report.

The main change of moyamoya disease (MMD) is steno-occlusion at the terminal portion of the bilateral internal carotid arteries (ICAs). Occlusion of distal portions of the bilateral vertebral arteries (VAs) in MMD has never been reported. An 18-year old female was admitted with repeated headache for 13years. Cerebral digital subtraction angiography (DSA) demonstrated occlusion of bilateral ICAs at their terminal portions, moyamoya vessels at the skull base, occlusion of bilateral distal VAs and the basilar artery (BA) fed by the tortuous collateral vessels arising from the cervical segment of VAs. We report this unique case for its rarity and discuss its mechanism.