Persistent Primitive Hypoglossal Artery Associated with Cerebral Aneurysm and Cervical Internal Carotid Artery Stenosis : Case Report

症例は71歳女性。主訴は眩暈発作。左頚動脈撮影にて persistent primitive hypoglossal artery (PPHA)と内頚動脈瘤を認め、さらにPPHA分岐部より中枢側の内頚動脈に高度狭窄を認めた。両側椎骨動脈は低形成で、脳底動脈はPPHAから造影された。内頚動脈瘤が破裂する危険性を考慮し、先ず動脈瘤のclippingを行った。1ヶ月後に頚動脈内膜切除術を内シャントを用いて行った。術中測定で内頚動脈の血流量は70ml/minと少なく、PPHAのstump pressurel は25mmHgと低値で後頭蓋窩の低灌流状態が強く疑われた。術後、眩暈発作は消失した。

A 71-year-old female had vertigo attacks once or twice a day secondary to vertebrobasilar insufficiency. Left carotid angiography revealed persistent primitive hypoglossal artery (PPHA) associated with a large internal carotid artery (ICA) aneurysm and severe stenosis of the ICA. The bilateral vertebral arteries were hypoplastic. The basilar artery was opacified via the PPHA but not via vertebral arteries. Clipping of the aneurysm was performed first because the risk of rupture of the aneurysm was not negligible. One month after clipping, carotid endarterectomy using a T-shaped shunt system was successfully performed. The postoperative course was uneventful and the vertebrobasilar ischemic attacks did not recur. Left carotid angiography demonstrated complete obliteration of the aneurysm and disappearance of the carotid artery stenosis. Low ICA flow (70 ml/min) and low stump pressure of the PPHA (25 mmHg) strongly suggested low perfusion of the posterior circulation. Carotid endarterectomy may be essential for augmentation of the posterior circulation in patients with PPHA associated with ICA stenosis.