田中 弘二

一過性脳虚血発作（transient ischemic attack; TIA）で入院中に発症した虚血性脳卒中に対しrt-PA 静注療法を施行した，既報の1 例を除く4 例を分析した．男性2 例，年齢74 から89 歳，先行したTIA のABCD2 スコアは4 から6，1 例に入院時拡散強調画像で左視床内側に高信号病変を認めた．4 例中3 例が心房細動を有し，入院時ないし発症時に主幹動脈閉塞所見がみられた．TIA から虚血性脳卒中発症までの時間は2 時間から3 日で，発症時のNIH Stroke Scale スコアは7 から30，発症からrt-PA 静注療法開始までの時間はそれぞれ33，33，160，170 分であった．90 日後のmodified Rankin Scale は0 が2 例，5 が1 例，不明1 例であった．TIA は入院後早期に虚血性脳卒中を発症する危険がありrt-PA 静注療法を含む超急性期治療の適応を念頭におく必要がある．

We herein report two autopsy cases of severe cardioembolic stroke with oscillating thrombi in the bilateral extracranial internal carotid arteries (ICAs) demonstrated on carotid ultrasonography performed on admission. An autopsy study of Case 1 conducted on the third hospital day revealed no thrombi, while that of Case 2 conducted on the 42nd hospital day revealed red thrombi in the extracranial ICAs. Our postmortem studies confirm that oscillating thrombi may be seen in the region of blood stasis caused by occlusion of the distal portion of the ICA, thus reflecting a pre-state of thrombus formation.<br>

An 85 year-old woman with hypertension and dyslipidemia was admitted with visual impairment, left hemiparesis, and sensory disturbance. A systolic bruit was not audible in her neck or supraclavicular fossa. Magnetic resonance imaging revealed a fresh infarct in the right occipital lobe and magnetic resonance angiography (MRA) showed occlusion of the right posterior cerebral artery (PCA). Carotid ultrasonography showed no stenotic lesions. We performed transesophageal echocardiography (TEE) and found a mobile lesion in the origin of the innominate artery. After several days, we performed real-time three-dimensional (3D) TEE for further evaluation. We found that the mobile lesion was stringy with a length of 2.7 cm and moving in a circle around the point of adhesion. We could also detect the lesion by ultrasonography with a sector probe from the superior thoracic aperture. The lesion could not be detected by cervical MRA or computed tomography angiography.<br>The patient had no cardiogenic embolic source such as atrial fibrillation or a right to left shunt. There was no abnormal vascular form of dissection or aneurysm. We considered the mobile thrombogenic lesion to have originated from a ruptured atherosclerotic plaque with thrombus.<br>3D TEE may be a useful method for real-time three-dimensional evaluation of a mobile lesion located in the innominate artery or aortic arch, which is often difficult to evaluate by other methods.

A 66-year－old man was admitted with dizziness, and suffering from hypertension, hyperlipidemia, brain hemorrhage, and brain infarction. There was a difference in blood pressure between the right arm (77/61 mmHg) and the left (120/60 mmHg) , and the pulse of the right radial artery was markedly diminished. A systolic bruit was audible in the right supraclavicular fossa. Doppler ultrasonography demonstrated a "post-stenotic pattern" in the right vertebral artery (VA) and right common carotid artery (CCA) , characterized by diminished peak systolic flow velocity. We then performed aortic arch angiography and confirmed the presence of severe innominate artery stenosis. The stenosis was successfully treated by balloon angioplasty and stenting. After the treatment, the pulse of the right radial artery became easily palpable, the post－stenotic pattern by Doppler ultrasonography normalized, and the blood pressures in the bilateral arms equalized. When Doppler ultrasonography indicates a post－stenotic pattern in the right VA and the right CCA, stenosis of the innominate artery and occlusion of the left VA should be investigated.

Angiotensin converting enzyme(ACE)阻害薬内服中，rt-PA静注療法直後に舌の血管性浮腫をきたした心原性脳塞栓症の1例を報告した．症例は75歳女性．高血圧症，慢性心房細動，慢性心不全に対しACE阻害薬(イミダプリル10 mg/日)内服中であった．来院時，意識障害，roving eye movement，右上下肢の不全片麻痺，重度の失語を認め，NIHSSは35点と評価した．頭部MRIにて左中大脳動脈領域に新鮮梗塞を認め，MRAにて左中大脳動脈M2以降の描出が不良であった．心原性脳塞栓症の診断で，発症から1時間43分でrt-PA投与した．rt-PA投与終了後，麻痺の改善を認め一時NIHSS 16点となったが，右優位の舌の著明な浮腫が出現し，メチルプレドニゾロン500 mg点滴投与を行った．rt-PA投与17時間後に意識障害の増悪，左不全片麻痺，右共同偏視が出現．MRIにて右中大脳動脈領域への脳梗塞再発を認めた．舌の浮腫は呼吸障害を起こすことなく36時間後には消失した．rt-PA投与後の血管性浮腫が舌に限局する場合は発見が遅れる可能性があり注意が必要である．

遺残原始舌下動脈(persistent primitive hypoglossal artery：PPHA)を伴い，脳底動脈への心原性塞栓によりtop of the basilar syndromeを来した1例を報告した．症例は94歳，女性．意識障害のため最終未発症時刻から15時間後，当院へ救急搬送された．来院時，深昏睡で自発運動はなく，眼球は正中固定し対光反射は消失，NIHSSは40点と評価した．心電図モニターにて心房細動を認めた．頭部MRIにて両側視床，大脳脚を含む中脳に新鮮梗塞を認めた．MRAにて右内頸動脈より分岐するPPHAから起始する脳底動脈が末端で閉塞している所見を認めた．PPHAを伴う症例においては椎骨動脈，後交通動脈などの後方循環の発達が悪く，症状が重篤化しやすいと考えられる．