Combined extracranial and intracranial atherosclerosis in Korean patients

OBJECTIVES: To evaluate the frequency of intracranial atherosclerosis among patients with steno-occlusive extracranial carotid artery disease and to determine if there are factors related to the combined intracranial atherosclerosis. DESIGN: Cross-sectional study. SETTING: A tertiary referral hospital.Patients We studied 142 consecutive patients who had atherosclerotic steno-occlusive lesions (defined as > or =30% narrowing of the luminal diameter or occlusion) of an extracranial carotid artery confirmed by conventional angiography. We excluded patients who had potential cardiogenic sources of embolism. Potential vascular risk factors for each patient were obtained from medical records.Main Outcome Measure We determined the location and severity of atherosclerotic lesions by conventional angiography. We compared the vascular risk factors between patients with steno-occlusive extracranial carotid artery disease alone and patients with combined intracranial atherosclerosis and extracranial carotid artery disease. RESULTS: Intracranial steno-occlusive lesions (> or =30% stenosis or occlusion) were found in 80 patients (56.3%). Of 121 patients with significant (> or =50% stenosis or occlusion) extracranial carotid artery disease, 58 (47.9%) also had significant lesions of intracranial arteries. Univariate and multivariate analyses showed that diabetes mellitus was the only significant factor associated with combined intracranial atherosclerosis in patients with extracranial carotid artery disease. CONCLUSIONS: Intracranial atherosclerosis is common in Korean patients with steno-occlusive extracranial carotid artery disease. Diabetes mellitus is associated with intracranial atherosclerosis in patients who had steno-occlusive extracranial carotid artery disease.     

Carotid artery auscultation--anachronism or useful screening procedure?

Carotid bruits are supposed to indicate the presence of high-grade common carotid or extracranial internal carotid artery stenosis in a large proportion of patients. Using a stethoscope, we prospectively auscultated 273 carotid arteries of 145 patients blinded to the results of a complete extracranial and intracranial Doppler investigation including extracranial color-coded duplex ultrasound. Fifty-four arteries showed stenosis of > or = 50%-99%, or occlusion of the extracranial internal or the common carotid artery. In 25 of these arteries, a bruit was present. In 9 out of 16 patients with extracranial stenosis from 70%-99%, a bruit was detected. In one additional patient with a middle-grade external carotid artery stenosis, a bruit was also present. In seven additional patients, a bruit was present in the absence of any carotid artery stenosis, cardiac vitium or goiter. The sensitivity of carotid auscultation for the detection of a 70%-99% stenosis of the common or extracranial internal carotid artery was 56% and specificity was 91%. The positive predictive value of a bruit found during carotid auscultation was 27%, and the negative predictive value of a normal auscultation was 97%. Carotid auscultation is a useful screening procedure in the detection of carotid stenosis or occlusion, but requires confirmation by carotid ultrasound.     

Rete mirabile bei segmentaler Agenesie der A. carotis interna

The term carotid rete mirabile refers to an anatomic structure common in several lower mammals (e.g., swine). The blood supply for the intracranial arteries originates from branches of the external carotid artery, predominantly the ascending pharyngeal and internal maxillary arteries. In these animals the intracranial internal carotid artery forms from a dense network of numerous converging, small-caliber vessels. An analogous structure is rarely found in humans. Associated with segmental agenesis of the internal carotid artery, so-called carotid rete mirabile can be observed. In it numerous tortuous vessels with a diameter of 1-2 mm are found along the expected course of the internal carotid artery and coming from branches of the external carotid artery. These vessels converge to the intradural paraclinoid segment of the internal carotid artery, which shows a normal diameter. This rare pattern of collateral supply to the brain is illustrated here on the basis of two clinical case histories. Both patients presented with aneurysmal subarachnoid hemorrhage. In one, histological examination of a vessel biopsy revealed medial fibromuscular dysplasia. In both patients the rete mirabile was found in only one carotid system. The affected carotid canal in the skull base was hypoplastic. Human carotid rete mirabile probably has no inherent pathologic significance, but its frequent association with other intra- and extracranial vascular pathologies should be kept in mind.     

Cerebrovascular angioplasty and stenting for the Prevention of stroke

Until recently, stroke preventive strategies have focused on either medical regimens aimed at antagonizing or reversing atherosclerosis, or surgical intervention for revascularization of the cerebrovascular system. However, with the advent of rapidly emerging microcatheterization techniques and technology, endovascular surgical revascularization of the brain is rapidly emerging as a powerful therapeutic modality. In particular, significant advances already have been made in revascularization of the extracranial carotid artery and many common anatomic sites of intracranial athero-occlusive disease, using special adaptations of conventional percutaneous angioplasty and stenting techniques. This paper reviews the cumulative experience with these emerging techniques, with a particular emphasis on clinical outcomes and future directions. It also reports the substantial cumulative institutional experience of the authors over the past 18 months with both extracranial carotid and intracranial artery stent-assisted carotid angioplasty.     

Comparison of transcranial and cervical continuous-wave Doppler in the evaluation of intracranial collateral circulation

Adequate intracranial collateral circulation reduces risk of stroke in carotid artery surgery. To evaluate their relative accuracies in assessing intracranial collateral blood flow, we prospectively compared transcranial Doppler and continuous-wave Doppler of the cervical carotid arteries combined with compression of the common carotid artery in 28 consecutive patients before carotid endarterectomy. Ten healthy volunteers served as controls. Three patients (11%) were excluded from compression of arteries because of diffuse disease in the common carotid artery. A total of 199 compressions were performed without complications. Lack of a suitable transtemporal window precluded the performance of transcranial Doppler in three patients (12%). The anterior communicating artery was identified in all the normal volunteers and 80% of patients by both methods. The posterior communicating artery was identified by both methods in 16 of 20 attempts in controls. Continuous-wave Doppler identified the posterior communicating artery in 30 of 50 attempts in patients; transcranial Doppler identified the posterior communicating artery in 20 of 44 attempts in patients (p greater than 0.5). Detection of intracranial collaterals correlated with intraoperative carotid artery back pressure measurements in 23 of 25 patients (92%). We conclude that continuous-wave Doppler of the extracranial arteries combined with common carotid artery compression is a safe and easy way to detect intracranial collaterals, with an accuracy equivalent to transcranial Doppler.     

缺血性脑血管病患者颅内外动脉狭窄分布研究

目的 研究缺血性脑血管病患者颅内外动脉狭窄分布特点.方法 本研究收集了1031例在院脑梗死和TIA患者的DSA资料,对其中资料完整的1000例患者进行分析.结果 DSA显示,1000例患者中有680例存在脑动脉狭窄,累计有1417条血管狭窄.发生部位依次为:大脑中动脉狭窄337条、椎动脉远端及基底动脉狭窄291条、颈内动脉颅外段狭窄280条、椎动脉起始段狭窄207条、颈内动脉虹吸段狭窄115条、大脑前动脉狭窄100条、大脑后动脉狭窄70条.大脑中动脉、椎基底动脉系统和颈动脉颅外段是最常见的动脉狭窄好发部位.颅内动脉狭窄331例,颅外动脉狭窄134例,颅内外动脉均见狭窄215例.结论 颅内动脉粥样硬化性狭窄仍是缺血性卒中的重要原因,最近三年,多发病变、颅外动脉病变检出率明显上升,值得关注,控制血压、血糖、血脂可预防脑动脉粥样硬化性狭窄的发生.     

Prevalence of extracranial carotid artery disease detectable by echo-Doppler in an elderly population.

BACKGROUND AND PURPOSE: Little information is available on extracranial carotid artery disease in free-living elderly individuals. We sought to evaluate the prevalence of carotid lesions in the elderly. METHODS: Using echo-Doppler, we assessed the prevalence of possible atherosclerotic lesions in the internal carotid arteries (n = 478) and the external and common carotid arteries (n = 956) of 239 subjects 65-94 years of age living in retirement homes in Seattle, Wash. RESULTS: We found that 152 (31.8%) internal carotid arteries were affected by nonstenosing plaque and 37 arteries (7.7%) had stenosis or occlusion. In addition, 193 (20.2%) external or common carotid arteries showed nonstenosing plaques. There were 128 subjects (53.6%) with internal carotid disease, 106 (44.3%) with evidence of external or common carotid disease, and 75 (31.4%) affected by disease in all three sites. There were 80 subjects (33.5%) with no ultrasound evidence of carotid disease. We found that the presence and severity of carotid disease increased between the decades 65-74 and 75-84. We also demonstrated a positive association between systolic blood pressure and ultrasound evidence of carotid disease that was independent of age. CONCLUSIONS: The prevalence of extracranial artery disease in an apparently healthy population was high, although stenoses in most instances were not severe. We conclude that noninvasive ultrasound methods identify a relatively small fraction of individuals (5% of the total) at high risk for stroke or transient ischemic attack. Echo-Doppler might be used to monitor further disease progression and to evaluate the efficacy of different therapeutic or preventive interventions.     

Risk factors for atherosclerosis of cervicocerebral arteries: intracranial versus extracranial

OBJECTIVES: To search for factors determining the site of atherosclerosis of the cervicocerebral arteries in patients from Bangkok (Thailand) with ischemic stroke in the carotid territory. MATERIAL AND METHODS: Patients with the clinical syndrome of stroke or transient ischemic attack in the carotid territory or with ocular stroke were retrospectively studied. They were divided into an intracranial and an extracranial carotid stenosis group based on their vascular imaging. The stroke risk factors were then compared. RESULTS: There were 49 cases with extracranial carotid stenosis and 51 with intracranial stenosis. Among the patients with extracranial stenosis, 98% had associated intracranial disease, whereas none of those with intracranial stenosis had more than 50% of extracranial carotid stenosis. The presence of diabetes mellitus and a history of ischemic heart disease were found to be significantly more prevalent among patients with extracranial internal carotid artery stenosis. CONCLUSION: Diabetes mellitus as well as a history of ischemic heart disease were found to be more significantly prevalent in patients with combined extracranial internal carotid artery and intracranial stenosis. Extracranial carotid stenosis might represent a more severe atherosclerotic process of the cervicocerebral circulation when compared with intracranial stenosis.     

缺血性脑血管病与颈动脉粥样硬化的关系

目的 探讨颈动脉粥样硬化与缺血性脑血管病的关系。方法 以2001年6月至2004年12月在我院住院的1583例急性缺血性脑血管病患者为研究对象，应用超声诊断仪检测双侧颈动脉，采用非条件Logistic回归分析颈动脉粥样硬化的危险因素及与缺血性脑血管病的关系。结果 86．5％（1369／1583）患者存在不同程度颈动脉粥样硬化；脑梗死组颈动脉粥样硬化患病率（1087／1266，85．9％）较短暂性脑缺血发作组（198／317，62．5％）高。颈动脉粥样硬化病变特点以斑块居多（1286／1583，81．2％），而中重度狭窄发生率较低（214／1583，13．5％）；颈动脉斑块以颈总动脉分叉处最多见（665／1286，51．7％）。斑块发生率及颅外段颈动脉狭窄程度与脑血管病危险因素有明显相关性。结论 佛山地区缺血性脑血管病患者颈动脉粥样硬化病变可能以斑块居多，颈动脉粥样硬化与缺血性脑血管病有关。     

缺血性脑血管病患者颈动脉内-中膜厚度及斑块分级对颅内外大动脉狭窄的预测价值

目的探讨缺血性脑血管病(ICVD)患者颈动脉内-中膜厚度(IMT)和斑块分级对颅内外大动脉狭窄的预测价值。方法对459例ICVD患者进行颈动脉IMT及斑块检测。采用数字减影血管造影(DSA)对患者颅内外大动脉进行检查。根据有无颅内外大动脉狭窄及狭窄部位将患者分为无动脉狭窄组、颅外动脉狭窄组、颅内动脉狭窄组和颅内外动脉狭窄组;根据狭窄程度又将各狭窄组分轻、中、重度狭窄亚组。比较各组间颈动脉IMT及斑块分级,分析其对颅内外大动脉狭窄的预测价值。结果本组中399例ICVD患者(86.9%)伴颅内外大动脉狭窄。各狭窄组间对应亚组的颈动脉IMT及斑块分级比较,差异均无统计学意义。各狭窄组中,中、重度狭窄亚组颈动脉IMT≥1.07 mm,斑块分级为3,均较无动脉狭窄组及轻度狭窄亚组显著增高(P<0.05~0.01)。ROC分析结果显示,颈动脉IMT增厚及斑块分级增加可预测中、重度颅内外大动脉狭窄(均P<0.01)。将颈动脉IMT≥1.07 mm及斑块分级为3作为预测中、重度颅内外大动脉狭窄的截断值,其敏感度均≥49.17%,特异度均≥81.67%,准确度均≥62.78%。结论颈动脉IMT≥1.07 mm及斑块分级为3对I...     

应用64排螺旋CT检测缺血性脑血管病与颈动脉斑块和狭窄的关系

目的探讨缺血性脑血管病与颈动脉斑块以及狭窄的关系。方法以2008年12月~2009年11月在苏大附二院神经内科住院的143例缺血性脑血管病患者为实验组;以同期67例无缺血性脑血管病患者为对照组,所有患者均行64排螺旋CT血管造影,检测其双侧颈动脉(颈总动脉、颈内动脉颅外段、颈内动脉颅内段)斑块类型以及狭窄程度。结果 143例缺血性脑血管病患者中,仅有14例(9.8%)患者未检测出明显斑块,斑块发生率为90.2%,各段颈动脉斑块检出率均明显高于非缺血性脑血管病患者。18.2%缺血性脑血管病患者存在轻度颈动脉狭窄,23.1%患者存在中度颈动脉狭窄,18.9%患者存在重度颈动脉狭窄,颈动脉完全闭塞的患者占8.4%,缺血性脑血管病患者颈动脉狭窄检出率(68.6%)明显大于非缺血性脑血管病患者(29.9%),两者差异具有显著统计学意义。结论颈动脉斑块的形成和颈动脉狭窄是造成缺血性脑血管病的主要原因。颈内动脉的狭窄比颈总动脉常见,且在颈内动脉颅内段,斑块以硬斑块为主,在颈总动脉中,尽管狭窄较颈内动脉相对少,但是斑块类型以软斑块为主,由此可推断在国人,造成缺血性脑血管病的主要原因为颈总动脉不稳定斑块的脱落和颈内动脉本身狭窄所致。     

Distribution and correlates of sonographically detected carotid artery disease in the Cardiovascular Health Study. The CHS Collaborative Research Group.

BACKGROUND AND PURPOSE: This article describes the prevalence of extracranial carotid atherosclerosis assessed by ultrasonography, its association with risk factors, and its relation to symptomatic coronary disease and stroke in men and women aged > or = 65 years. METHODS: Maximum percent stenosis, maximum common carotid artery wall thickness, and maximum internal carotid artery wall thickness were assessed using duplex ultrasound in 5,201 men and women aged > or = 65 years in the Cardiovascular Health Study, a study of the risk factors and natural history of cardiovascular disease in the elderly. Existing coronary disease and stroke were assessed by physical examination and participant history. RESULTS: Detectable carotid stenosis was present in 75% of men and 62% of women, although the prevalence of > or = 50% stenosis was low, 7% in men and 5% in women. Maximum stenosis and maximum wall thickness measurements increased with age and were uniformly greater at all ages in men than in women (p < 0.00001). Established risk factors for atherosclerosis (hypertension, smoking, diabetes) and indications of vascular disease (left ventricular hypertrophy, major electrocardiographic abnormality, bruits, and history of heart disease or stroke) related to all three carotid artery measures in the elderly. Of the three ultrasound measures, the best correlate for a history of coronary disease was maximum internal carotid artery wall thickness. For stroke the best correlate was common carotid artery wall thickness. Multiple logistic regression models of prevalent coronary heart disease and stroke that included the ultrasound findings indicated, after adjustment for age and sex, that maximum internal wall thickness and maximum common carotid wall thickness were significant correlates of both. Maximum stenosis did not add significantly to the correlation. CONCLUSIONS: In the elderly the incidence of carotid atherosclerosis was high, although the frequency of severe disease was low. The prevalence and severity of carotid atherosclerosis continued to increase with age even in the late decades of life, and more disease was found in men than in women at all ages. Known risk factors for atherosclerosis continued to relate to carotid abnormalities in the later decades of life, both in symptomatic and asymptomatic subjects.     

Associations of risk factors with segment-specific intimal-medial thickness of the extracranial carotid artery

BACKGROUND AND PURPOSE: It is generally assumed that risk factors affect extracranial carotid intimal-medial thickness similarly among all arterial segments. This assumption underlies use of single segments or walls of segments as outcome variables for risk factor studies and clinical trials. However, if the impact of risk factors was unequal for various segments or circumferentially asymmetrical within segments, then inferences drawn from a single segment or wall might not be generalizable; furthermore, since individual segments and walls have unique histological characteristics and are differentially exposed to turbulent flow, risk factor relationships with a particular segment or wall may provide inferences regarding pathogenesis of atherosclerosis. METHODS: We evaluated associations of risk factors with intimal-medial thickness at the near and far walls of the common carotid artery, bifurcation, and internal carotid artery in 280 individuals older than 45 years equally divided between coronary artery disease cases and controls and between men and women. RESULTS: The patterns of differences in mean intimal-medial thickness among segments vary, depending on age, history of hypertension, body mass index in women, and coronary (case-control) status. The asymmetry of disease depended on blood glucose concentrations, prior history of diabetes, smoking, and coronary status. Sex, postmenopausal status, LDL cholesterol, systolic blood pressure, and history of myocardial infarction all had statistically significant relationships with intimal-medial thickness that were fairly homogeneous among arterial sites. CONCLUSIONS: Focus on an individual segments or walls of the extracranial carotid arteries may lead to overestimation or underestimation of associations of risk factors with extracranial carotid intimal-medial thickness.     

脑梗死患者的颅外颈动脉超声与CT血管造影的比较

目的:比较颈部超声检查与颈部CTA对颅外颈动脉硬化性狭窄斑块的敏感性。方法:对比分析我科住院的61例脑梗死患者的双侧颈总动脉、颈动脉分叉处、颈内动脉超声检查和CTA检查结果。结果:61例患者中,超声发现斑块110处,CTA发现斑块124处,两者对于颈动脉的斑块检出率差异无显著性意义,两者狭窄程度的一致性是55%,但CTA对颈动脉分叉处斑块敏感性高于超声波检查,对钙化斑更敏感。超声检查血管狭窄的程度高于颈部CTA的结果,超声未能显示椎动脉异常。结论:脑梗死患者的颈部CTA检查优于超声检查,特别适用于椎基底动脉供血不足患者。     

Racial differences in ischemic cerebrovascular disease: Clinical and magnetic resonance angiographic correlations of white and asian patients.

Objectives. We explored racial differences in ischemic cerebrovascular disease. Methods. Clinical and magnetic resonance angiographic (MRA) features were compared in 21 white and 21 Asian patients with symptomatic ischemic cerebrovascular disease. Results. When all carotid artery sites were combined and compared, whites had more stenotic lesions of internal carotid artery origin, and Asians had more stenotic lesions of the middle cerebral artery (MCA) stem. In the vertebrobasilar territory, there were no significant differences in the distribution of extracranial and intracranial stenotic lesions between the two races. In symptomatic territories, the distribution of extracranial and intracranial stenosis were not significant differences for white and Asian patients. In asymptomatic territories, whites had a higher tendency for isolated extracranial stenosis, whereas Asians had an increased incidence of isolated intracranial stenosis. In the combined symptomatic and asymptomatic, carotid and vertebrobasilar territories, there was an increased incidence of extracranial carotid stenotic lesions in white patients and intracranial anterior circulation stenotic lesions in Asians. Demographic factors alone seemed to explain the difference. Conclusions. Racial differences in the occurrence of extracranial and intracranial lesions raise the possibility of different pathophysiologic abnormalities.     

Use of sonography to evaluate carotid atherosclerosis in the elderly. The Cardiovascular Health Study. CHS Collaborative Research Group

Carotid sonography is being performed on more than 5,000 participants in the Cardiovascular Health Study, a prospective, multicenter study of cardiovascular disease in men and women aged 65 years and older. The sonographic methods used to examine and measure the extracranial carotid arteries are described. Initial validation studies were performed on 61 subjects with a mean age of 68.6 years. Analysis of within- and between-sonographer differences and between-reader differences were performed for selected variables. In general, the mean absolute differences for within- and between-sonographer comparisons were small, with even less variability between readers. Variability was less for the common carotid artery than for the internal carotid artery. These data suggest that carotid sonography is a reliable and reproducible method for use in the study of carotid atherosclerosis in population studies.     

Occipital infarction with hemianopsia from carotid occlusive disease

Extracranial internal carotid artery occlusive disease usually produces stroke in the middle cerebral artery territory or the border zone between the middle and anterior cerebral arteries. It is unusual for occipital infarction in the posterior cerebral artery territory to be caused by internal carotid artery disease despite the fact that the posterior cerebral artery may arise directly from the internal carotid artery as an anatomic variation. We describe a patient with a fetal posterior cerebral artery originating from the internal carotid artery, and the initial manifestation of his extracranial internal carotid artery occlusive disease was hemianopsia from occipital infarction.     

Isolated Petrous Carotid Stenosis and Transient Ischemic Attack

Although anterior circulation transient ischemic attacks (TIAs) tend to be more common in patients with extra- cranial carotid arterial disease than in those with intracranial carotid or middle cerebral arterial disease, the authors recently encountered 4 patients with both recurrent, stereotypical TIAs as well as isolated stenosis of their petrous internal carotid artery (ICA). While the gold standard for establishing the diagnosis of intracranial large-artery disease has always been conventional angiography, magnetic resonance angiography changes, confirmed with intra-arterial digital subtraction angiography in 2 of these patients, were quite sufficient to define the occlusive disease in each of the cases. Petrous ICA stenosis is not uncommon, but it has often been overshadowed by the search for extracranial ICA disease that might be amenable to surgical reconstruction.     

彩色多普勒超声检查对颈部动脉狭窄的诊断价值

目的 研究彩色多普勒超声检查对颈部动脉狭窄的诊断价值.方法 对145例缺血性脑血管病患者进行颈部动脉彩色多普勒超声及数字减影血管造影(DSA)检查.以DSA检查结果为标准,分析彩色多普勒超声检查对颈部血管狭窄的敏感性和特异性.结果 本组患者彩色多普勒超声检查对诊断颈动脉分叉部狭窄的敏感性和特异性分别为96.8%和80.6%,对锁骨下动脉狭窄为60.0%和98.7%,对椎动脉狭窄为33.3%和89.0%.彩色多普勒超声检查诊断颈动脉分叉部、锁骨下动脉和椎动脉狭窄的准确度为93.0%、92.8%和82.1%.结论 彩色多普勒超声检查可作为诊断颈动脉分叉部位血管狭窄的有效方法;而其对锁骨下动脉及椎动脉狭窄的敏感性较低,诊断价值不大.     

Treatment of carotid artery stenosis by elective stent placement instead of carotid endarterectomy in patients with severe coronary artery disease

Patients with concomitant cardiac and cerebrovascular disease undergoing revascularization procedures are at high risk of both, cardiac and cerebrovascular complications. The purpose of our study was to evaluate the feasibility of prior elective carotid artery stenting as an alternative treatment procedure to carotid endarterectomy (CEA) in patients with concomitant coronary artery disease (CAD), who clearly needed coronary revascularization. We offered extracranial internal carotid stenting to 85 patients with 89 significant carotid stenoses. Out of these, 19 patients were symptomatic. The quantitative mean reduction in diameter was 77 +/- 11%. Stent implantation was successful in 88 lesions. Two disabling major and 3 reversible minor strokes occurred periprocedurally. Three patients showed asymptomatic restenosis and stent deformation was detected in 2 patients. Based on this experience, carotid stenting in high risk patients with severe coronary artery disease is feasible and safe and might be indicated as an alternative procedure for combined surgery.