Persistent Primitive Hypoglossal Arteryの2例について—脳動静脈奇型を伴った9歳男子の1例及びBrain Stem Syndromeをきたした55歳男子の1例

STUDIES ON 2 CASES OF A PERSISTENT PRIMITIVE HYPOGLOSSAL ARTERY: CASE REPORTS ON A 9-YEAR-OLD MALE PATIENT WITH ARTERIOVENOUS MALFORMATION AND A 55-YEAR-OLD MALE PATIENT WITH BRAIN STEM SYNDROME

Ｉ．はじめに

　先天性脳血管異常として知られる内頸動脈脳底動脈吻合遺残の1つであるpersistent primitive hypoglossalartery （以下P．H．Aと略す）は脳血管撮影の普及に伴いその報告例も増加している。クモ膜下出血発作，脳腫瘍，頭部外傷、脳の奇形疾患等の補助診断法としての脳血管撮影により偶発的に発見されたものがほとんどで，遺残動脈による症状，例えばこの動脈による神経の圧迫による症状，頭部回旋時にみられる失神発作^{8）10）27）}異常血流による耳鳴^6）等に対する血管撮影で発見されることはむしろ少ない。クモ膜下出血発作は原因の明らかなものはほとんどが合併する脳動脈瘤破裂によるもので脳動静脈奇型の破裂によるクモ膜下出血発作はpersistenttrigeminal artery, persitent otic arteryの場合に各1例見られたのみである。我々は最近脳動静脈奇型を合併しこれの破裂によるクモ膜下出血発作の症例とbrainstem syndromeと思われる意識障害の症例にP．H．A．を合併した2症例を経験した。脳動静脈奇型症例は入院中第2回目のクモ膜下出血発作を来たし手術を待たずして死亡した為，剖検所見と脳血管撮影所見を報告しP．H．A．脳底動脈，椎骨動脈の発生学，脳血管写像，P．H．A．と脳血管障害について考察を試みた。

We have reported 2 cases of a persistent hypo-glossal artery.

Case 1 : The patient was a 9-year-old male. His initial symptoms were sudden onset of headache and left hemiplegia. As bloody c.s.f. was demon-strated by the spinal tap, a diagnosis of subarach-noid hemorrhage was established and r-CAG wasperformed. A persistent hypoglossal artery was recognized at the height of the first cervical vertebra (C₁ level) of the internal carotid artery. The thin posterior communicating artery on the right side and vertebral artery on the both sides were noticed. Addition to those arteries, right posterior inferior cerebellar artery was demonstrated as a branch of the right anterior inferior cerebellar artery. Arteriovenous malformation fed by the anterior cerebral artery and the posterior parietal artery was demonstrated at the right parietal region. The second attack of subarachnoid hemor-rhage led the patient to death. At autopsy it was observed that the circle of Willis was normal and the persistent hypoglossal artery entered into the intracranial space passing through the dura with a right hypoglossal nerve. Vertebral artery was recognized on the both sides, espesially hypoplastic on the right side. An intracerebral hematoma was observed at the right parietal region.

Case 2: The patient was a 57-year-old male. On July 9, 1970 he was found lying down in un-consciousness by his family member. He was admitted to a certain hospital, and from around July 20 he got a recovery of his consciousness and regained the ability to walk with the help of another, so that he was discharged on January 25, 1971. He visited our clinic for an exact examina-tion on January 13, 1972. It revealed neurological findings such as drowsiness and bilateral oculomotor nerve palsy. The right retrograde brachial angio-graphy demonstrated right vertebral artery hypo-lastic and non-filling at the C₃ level. A persistent hypoglossal artery was recognized branching off from the internal carotid artery at the C₂ level. Nonfilling appearance of right posterior communi-cating artery was recognized. The right posterior inferior cerebellar artery was branching off from the persistent hypoglossal artery. L-VAG showed the left vertebral artery hypoplastic and nonfilling beyond the point from where it branched off the left posterior inferior cerebellar artery.

There have been no case-reports on a persistent hypoglossal artery complicated by arteriovenous malformation. Subarachnoid hemorrhage of which causes were clear unexceptionally had an aneurysm on the same side. As our case also had an arterio-venous malformation on the same side, it was supposed as a series of malformation on the way of the development of the cerebral vessels. The circle of Willis was found normal in our case as well as in Oertel's case. We have reviewed the literatures and discussed about the developments of the cranial artery and the cerebral angiographic appearances of the persistent hypoglossal artery.