アポリポ蛋白Eの各表現型,特にε4保有の有無と虚血性脳血管障害発生との関連を脳ドック受診例を中心に,既知の危険因子を含め検討した.対象は40歳以上70歳未満(平均60±7歳)の無症候性脳梗塞(ラクナ梗塞)31例,無症候でMRAにより診断された50%以上の頭蓋内主幹動脈狭窄25例(平均58±7歳),既往に脳梗塞がなくMRI,MRA上にも病変のない対照200例(平均59±6歳)である.頭蓋内主幹動脈狭窄郡ではε4保有率が高く,既知の危険因子を含め検討しても,特にε4と狭窄群には有意な相関(p<0.05)がみられた.無症候性脳梗塞群と高血圧との間には相関がみられたが,ε4との有意な関連は認められなかった.穿通枝領域のラクナ梗塞と頭蓋内主幹動脈狭窄では,通常病態発生機序や成因は異なるものである事を再確認すると共に,ε4が頭蓋内主幹動脈狭窄症例の原因となるアテローム血栓の発生に関与していると推察した.

抄録全体を表示

軽度狭窄性頸動脈病変例の予後を知る目的で,60歳以上の347例に頸動脈超音波検査を行ない,生命予後を検討した.頸動脈病変は広がりから無病変群(n=153),片側病変群(n=103),両側病変群(n=91)に,形態からnodular plaque群(n=66),mural plaque群(n=118),軽度狭窄群(n=10)に分類した.平均3.9年の追跡期間で66例が死亡した.脳梗塞,虚血性心疾患を併せた血管性事故による年間死亡率は無病変群の0.5%に対して,広がり別では片側病変群1.7%,両側病変群4.0%,形態別ではnodular plaque群1.8%,mural plaque群3.6%,狭窄群0%で,両側病変群,mural plaque群の予後が悪かった.ハザード比も血小板凝集能亢進とともに両病変が有意に高かった.以上から軽度狭窄性病変でも広範な病変例やmural plaque例では血管性事故による予後が悪く,この中には抗血小板療法が考慮されるべきものが含まれていた.

抄録全体を表示

Screen filtration pressure(SFP)法による全血血小板凝集計を用いて,チクロピジン(TIC)とアスピリン(ASA)の抗血小板作用を測定し,比濁法と比較した.対象は脳血栓症慢性期患者85例(TIC群51例,ASA群34例),対照群25例である.全血凝集の測定はADPとcollagenを凝集惹起物質として採血5分後と60分後に行い,血小板凝集能の指標として血小板凝集閾値係数(PATI)を算出した.TIC群とASA群の全血凝集能は,対照群に比べて抑制されていた.全血ADP凝集は,対象群とTIC群では採血5分後より60分後で高値を示したが,ASA群では変化がなかった.全血collagen凝集は,TIC群では採血5分後より60分後で高値を示したが,対照群とASA群では変化がなかった.全血凝集能と比濁法では,ADP凝集では3群で,collagen凝集ではTIC群で負の相関があった.全1血SFP法は,抗血小板薬の評価に有効であった.

抄録全体を表示

脳梗塞発症24時間以内から3～5週にかけて,リンパ球接着分子LFA-1の発現が経時的に上昇することを報告した.今回,慢性期ラクナ梗塞40例,健常対照25例を対象にリンパ球接着分子LFA-1,VLA-4とそのリガンドである血管内皮接着分子ICAM-1,VCAM-1を測定し,脳血管障害危険因子との関連について検討した.LFA-1,VLA-4はflow cytometerを用いリンパ球の高発現分画(%)を,可溶性(s)ICAM-1,sVCAM-1はELISA法で測定した.その結果,LFA-1α・βとsICAM-1はいずれも健常対照に比較し有意な高値を示した.一方,VLA-4βには有意差がなかったが,sVCAM-1は有意な高値を認めた.脳血管障害危険因子との関係ではLFA-1a・βは喫煙,sVCAM-1は糖尿病,喫煙で高値傾向を示した.

抄録全体を表示

症例は68歳,男性.突然の右半身の触覚低下,深部覚脱失,右頸部から肩にかけての全感覚脱失,軽度の右片麻痺,排尿障害で発症した.MRIのT2強調画像にて右側の下部延髄から高位頸髄の後脊髄動脈領域に限局した高信号域を,右椎骨動脈内にintimalflapを認め,脳血管造影にて右椎骨動脈のtapering occlusionを認めたことから椎骨動脈解離に起因する後脊髄動脈領域の脊髄梗塞と診断した.脊髄梗塞の中でも椎骨動脈解離により後脊髄動脈症候群を来した症例はまれであり,貴重な症例と考えられた.

抄録全体を表示

症例は74歳,女性.薬物療法に反応せず,左上下肢の脱力が進行したため,発症4日目に紹介入院となった.意識レベルはJCSI-2であり,右方共同偏視,左半側空間無視,MMT2/5の左片麻痺がみられた.来院時の頭部MRI拡散強調画像で,既に右深部境界領域の梗塞像が出現し,灌流画像では右大脳半球の平均通過時間の延長がみられた.脳血管造影を施行すると右内頸動脈起始部に高度狭窄病変が存在した.経皮的脳血管形成術を施行したが,直後には臨床上の改善はなく,入院3日目より,高気圧酸素療法を開始したところ,1回目の治療終了直後から意識は清明化し,共同偏視や半側空間無視は消失した.左上下肢の脱力も日々改善し,計12回の高気圧酸素療法終了時の入院16日目には,MMT4/5の左片麻痺の状態で転院した.内頸動脈高度狭窄による進行性脳梗塞では,発症から4日目でも血行再建術と高気圧酸素療法の併用が有効な例がある.

抄録全体を表示

Recent changes in lifestyle have caused an increase in extracranial internal carotid artery (ICA) lesions in Japan. The prevalence of severe ICA atherosclerosis with>50% stenosis in the Suita City was 4.4% (7.9% in men and 1.3% in women), being almost equal to that reported in developed western countries. Several clini-cal studies also indicated that atherothrombotic brain infarction particularly due to extracranial ICA lesions has rapidly been increasing in frequency in Japan. The ICA lesions have strong relationships to cardiovascu-lar risk factors and coronary heart diseases.
Carotid ultrasonography is a rapid, noninvasive and accurate way to examine ICA lesions. Diffusion MRI studies will provide new knowledge how ICA lesions produce infarcts particularly in borderzone areas.
The efficacy of carotid endarterectomy (CEA) in the management of severe ICA stenosis was established in US, Canada, and Europe, but not in Japan. Carotid artery stenting remains a matter of investigations. Clini-cal evidence on the effectiveness and limitations of such surgical interventions and medicla management with antithrombotic agents and HMG-CoA blockers should be collected for Japanese patients with ICA lesions.

抄録全体を表示

We have experienced 188 carotid endarterectomies for symptomatic and asymptomatic carotid stenosis. From those experiences we proposed issues as indicated above. Pathological features of the Japanese plaque are similar to those of the American Caucasians. The Japanese plaques are rather early stage of the disease. Pathological feature of familial hypercholesterolemia in Japanese patients is identical of the Americans, suggesting importance of diet. Discussion on evidence-based medicine (EBM) is focused on carotid endarterectomy. Surgical indication for asymptomatic carotid stenosis is a matter of issue and we should be careful for EBM data reading. Post endarterectomy restenosis is not a rare condition and we should pay attention to this pathology. Our experience is presented. Endarterectomy versus endvascular stent placement is a matter of issue and we discussed indications for those procedures. Finally, request from neurosurgeon to internist is listed.

抄録全体を表示

Atherosclerosis in cervico-cephalic arteries is a lesion responsible for atherothrombotic brain infarcts. The pathological studies on the diversity of brain infarcts found in the autopsy cases with significant athero- sclerosis of the carotid arteries are summarized. All five autopsy cases with occlusive carotid thrombosis showed arterial territorial infarcts and no borderzone infarcts. Fifteen autopsy cases with atheromatous embolism in the brain, however, showed two types of brain infarcts (6 with arterial territorial infarct, 9 with bor-derzone infarct). This diversity of the lesion appeared to be correlated with histological features of the embolic materials (cholesterol crystal with or without other atheromatous components, especially fibrin). These variation in the components of the emboli may determine the size and location of the lodged arteries and feasibility of re-opening and hemorrhagic transformation. Recent development of transcranial Doppler and diffusion-weighted MRI enabled us to betect and follow-up very early stage of brain embolism and their silent recurrence, and may be valuable for clarifying the pathophysiology of brain embolism which occur based on the carotid atherosclerosis.

抄録全体を表示

Oxidized LDL (Ox-LDL) has been suggested as a key factor in atherogenesis. Ox-LDL can be specifically bound and internalized by Ox-LDL receptors, which transforms macrophages into foam cells and induces proinflammatory responses in vascular cells. These play crucial roles in the formation and deatabilization of atherosclerotic plaques. LOX-1 is a 40-50 kDa type II membrane glycoprotein, which acts as a cell surface receptor for Ox-LDL, in vascular endothelial and smooth muscle cells as well as macrophages. Ox-LDL uptake by LOX-1 down-regulates Bcl-2 expression, uprgulates Bax expression, and thereby induces apoptosis of cultured vascular smooth muscle cells. In addition, expression of Bax and LOX-1 was colocalized in atherosclerotic lesions of human carotid arteries. SR-PSOX, a novel class of Ox-LDL receptor in macrophages, is a type I membrane glycoprotein whose molecular weight is appoximately 30kDa. SR-PSOX is abundantly expressed by macrophages, but not smooth muscle or endothelial cells, accumulated in the intima of human carotid atherosclerotic plaques. Ox-LDL receptors, such as LOX-1 and SR-PSOX, may play key roles in atherosclerotic plaque formation including human carotid arteries.

抄録全体を表示

Carotid endarterectomy has been established as the gold standard for the treatment of carotid stenosis. However, patients with high risk characteristics including advanced age, heart/lung diseases, diabetes mellitus, and vascular co-morbidities represent a large segment of the perioperative morbidity and mortality reported from endarterectomy trials. Carotid stenting has been presented as an alternative treatment especially for these high risk patients for several years. Recently, Wholey et al. repoted the outcome of carotid stenting collecting from a large number of hospitals. The initial success rate of stent implantation was 98.4%, and the complication rate within 30 days after the procedure were as follows ; transient ischemic attack : 2.82 %. minor stroke : 2.72%, major stroke : 1.49%, death: 0.86%. According to this report, carotid stenting seems feasible and safe. However, carotid stenting has two major problems to be solved, distal embolization and restenosis. Distal embolization of atherosclerotic debris as a consequence of stent implantation was the major reason of neurological complications, however recent investigations showed that distal protection devices can reduce the complication caused by distal embolization markedly. Restenosis, renarrowing of the lesion, was another problem, however the newest technology and knowledge developed in the field of cardiovascular interventions will solve this problem.

抄録全体を表示

Stroke patients have longer length of hospital stay. After the introduction of 3 types of critical pathway dedicated for various severity of acute ischemic stroke in 1995, the average length of hospital stay of both stroke and non-stroke patients declined from 30.0 days (1993) to 14.9 days (1999) in our hospital. Rehabilitation in the recovery stage could be done in the specialized rehabilitation hospitals within Kumamoto due to inter-hospital cooperation. Our acute stroke team can concentrate on the treatment of stroke in the acute stage (within 2-3 week from the onset). We have been developing this stroke management system based on an acute stroke unit with referral to a rehabilitation unit in other hospital (inter-hospital referral model) in contrast to the conventional system with a combined acute and rehabilitation stroke unit in a single hospital (intra-hospital referral model). Eight-hundred and six patients (459 male, 347 female, 71.0±12.2 years old) with acute ischemic stroke were admitted to three hospitals between May 1999 and April 2000. The average NIHSS was 8.2 (median 5). 41.3% of the patients admitted within 3 hours of stroke onset. The length of hospital stay was 17.3±17.4 (median 14) days. Two-fifth of all patients discharged to their home, and 76.6% of them discharged within 14 days. Another 2/5 patients were transferred to rehabilitation hospitals, and 62.1% of them discharged within 21 days. The reduction of length of hospital stay was achieved by the use of critical pathway and the inter-hospital cooperation.

抄録全体を表示

Recent advances of diagnosis and therapy have been promoting the improvement of clinical outcomes in stroke patients. However, procedures for diagnosis and therapy have been complicated according to the advance, and the sufficient knowledge and medical ability are required in the stroke treatment. Stroke care unit (SCU) has been introduced to emergency medical centers in Japan, but its criterion has not been fully established especially for medical staffs. The guideline for stroke management will be published by the joint committee in the next year. For acute stroke patients, it is desirable that the medical specialist carry out the treatment according to the established guideline in SCU. Applying SCU for the improvement of the clinical outcome, the medical specialist is necessary for carrying out the complicated stroke treatment and the management of medical team in SCU.
For the stroke management in a local community, the medical specialist in SCU is suitable for the role of establishing the cooperative medical care system with hospitals and pre-hospital teams.
In the present time, stroke patients are treated in neurosurgical department, neurological department, cardiological department, emergency medical department or other departments. Only a small number of hospitals have SCU. Therefore, the level of stroke treatment should be standardized between those departments. For this purpose, the system of medical specialist for stroke treatment is available.
The establishment of the board qualified system for medical specialist for stroke treatment is required to improve the clinical outcome of stroke patients and necessary in the effective management of SCU. The name of board qualified strokologist is appropriate for such a medical specialist.

抄録全体を表示

In the begining of this century, a dramatic increase of stroke patients is expected in concomitant with continuous increase of older-age population in the developed countries. There are three major phases for stroke management: primary prevention, treatment at acute and chronic phases of stroke. First, we focused on the importance of effective population approach for reducing the mean level of causative risk factors. Selfrating stroke risk scoring system should be developed and prevailed by using modern information technology. Among people at particularly high risk of stroke, genome-based tailor-made prevention strategy should be established. Through the basic research on 'ischemic tolerance', vaccination against stroke should also be developed in the future. Second, we focust on effective treatment of brain attack by establishing primary stroke centers, where other than thrombolytic therapy neuroprotective approaches such as mild hypothermia and gene theapies would become possible. Finally, we focused on the importance of secondary prevention based on pathophysiological mechanism of each patient and well-organized comprehensive rehabilitation based on the promotion of understanding of molecular mechanism of neuronal prasticity. Regenerative medicine such as stem cell seeding and promotion of neurogenesis in the damaged brain should be developed for chronic phase of patients in the near future.

抄録全体を表示