脳血管撮影により発見された内頸動脈・脳底動脈吻合遺残の2例

2 CASES OF PERSISTENT CAROTIDBASILAR ANASTOMOSIS:Primitive Trigeminal and Hypoglossal Artery

I．緒言

　近年脳血管撮影法の進歩，普及によつて種々の脳血管奇形を育する症例の報告が見られるようになつてきている。内頸動脈・脳底動脈吻合遺残persistent carotid ba—silar anastomosisもその一つで胎生期脳発育過程における原始動脈の残存に基づくものである。この内頸動脈・脳底動脈吻合遺残としてはprimitive trigeminal artery，primitive acoustic arteryおよびprimitive hypoglos—sal arteryの三者が代表的なものであるが，これらの報告例が増すにつれて，遺残動脈と神経症状との関連についても検討が行なわれるようになつてきている。

　著者らは前交通動脈瘤症例と頭部外傷症例のおのおのに脳血管撮影により内頸動脈・脳底動脈吻合遺残を発見し，前者はprimitive trigeminal artery，後者はprim—itive hypoglossal arteryであることを明らかにしたので，これらの症例について報告するとともに，胎生学的ならびに臨床的意義についても述べてみたいと思う。

Cerebral angiography are routine examination procedure in neurological and neurosurgical field at present time and demonstration of the various vas-cular changes of central nervous system became easier.

The persistent carotid-basilar anastomosis, primit-ive trigeminal, acoustic and hypoglossal arteries, are typical congenital anomaly of intracranial artery and the number of these anomalies shall increase due to extensive use of cerebral angiography.

The authors had experienced 2 cases who has per-sistent carotidbasilar anastomosis demonstrated an-giographically.

The first case is 34 year old man who admitted with spontaneous subarachnoid hemorrhage. The carotid cerebral angiography done to reveal the ce-rebral aneurysm and demonstrated the primitivetrigeminal artery on right side beside anterior com-municating aneurysm.

The second case is 36 year old house wife who admitted with anisocoria after head injury. The carotid cerebral angiography had scheduled to exa-mine the intracranial hematoma and demonstrated the primitive hypoglossal artery on right side with-out evidence of traumatic intracranial hematoma. The intracranial blood circulation of this case had examined in detail by brachial cerebral panangio-graphy and proved that the development of ipsilate-ral vertebral artery was very poor with blind end in the level of third cervical spine.

The majority of persistent carotid-basilar anasto mosis had observed accidentaly and authors cases had also demonstrated by cerebral angiography do-ne for another diagnostic object.

However the clinical symptom of persistent car-otid-basilar anastomosis did not pointed by another authors out, it is very interesting from stand point of embryology that the primitive trigeminal artery had observed in the case of anterior communicat-ing aneurysm.