[Moyamoya disease with persistent primitive hypoglossal artery. Case report].

A 44-year-old female developed aphasia and visual disturbance of the left eye. Four-vessel angiography showed occlusion of the extra- and intracranial portions of the right internal carotid artery, severe stenosis of the left internal carotid fork, bilateral moyamoya vessels, and a persistent primitive hypoglossal artery on the left side. Measurement of cerebral blood flow by 133xe inhalation revealed decreased flow and no response to acetazolamide loading in the left cerebral hemisphere. The patient underwent superficial temporal artery-middle cerebral artery anastomosis, first on the left and then on the right side. There have been no other reported cases of moyamoya disease associated with a persistent primitive hypoglossal artery. Although the cause of moyamoya disease remains to be established, it is generally believed that stenotic changes of the carotid fork cause the development of moyamoya vessels as collateral pathways. According to this theory, there is no significant etiological relationship between moyamoya disease and persistent primitive hypoglossal artery. However, persistent primitive hypoglossal artery is compatible with moyamoya disease in terms of providing a collateral pathway via the vertebrobasilar system.