Relationship between the Oxfordshire Community Stroke Project classification and vascular abnormalities in patients with predominantly intracranial atherosclerosis

BACKGROUND: The Oxfordshire Community Stroke Project (OCSP) classification is a stroke classification based on clinical features collected at bedside. Previous studies reported good correlation between vascular abnormalities and OCSP mainly in populations not at risk of intracranial atherosclerosis. There have been limited data on the relationship between intracranial atherosclerosis and the OCSP classification. METHODS: Consecutive Chinese patients admitted to a regional hospital with acute ischemic stroke were studied in Hong Kong. Stroke subtype was classified as total or partial anterior circulation infarct (TACI or PACI), posterior circulation infarct (POCI), or lacunar infarct (LACI), according to the OCSP method. Transcranial Doppler (TCD) was performed whenever possible to evaluate the intracranial arteries as well as the carotid arteries. National Institute of Health Stroke Scale (NIHSS) was used to assess the severity of stroke on admission. RESULTS: Six hundred and ninety-nine consecutive patients were studied. On admission, 24 patients were classified as TACI (3.4%), 96 PACI (13.7%), 111 POCI (15.9%), and 468 LACI (67.0%). Of the 345 patients who had TCD evidence of intracranial or carotid artery abnormalities, 75% had intracranial involvement only, 5% extracranial involvement only and 20% had both intracranial and extracranial involvement. The frequencies of arterial abnormalities were found in 58% of TACIs, 48% of PACIs, 48% of POCIs and 50% of LACIs. There was no evidence that the frequencies of arterial abnormalities were different between the OCSP groups (P=0.8). Middle cerebral artery velocity was abnormal in 9 TACIs (38%), 32 PACIs (33%), 35 POCIs (32%) and 177 LACIs (38%) (P=0.6). Vertebrobasilar velocities were abnormal in 4 TACIs (17%), 20 PACIs (21%), 29 (26%) and 87 LACIs (19%) (P=0.3). The OCSP subtypes were associated with POCIs the severity of stroke. NIHSS score of > or =9 was found in 83% of TACIs, 18% of PACIs, 9% of POCIs, and 12% of LACIs (P<0.0001). CONCLUSIONS: OCSP classification is not significantly related to the presence of vascular abnormalities among patients with predominantly intracranial atherosclerosis.     

Circulating microemboli in 33 patients with intracranial arterial stenosis.

BACKGROUND: Intracranial arterial stenosis is a rare cause of stroke in Caucasians. Detection of clinically silent circulating microemboli by transcranial Doppler sonography is now widely investigated in patients with carotid artery disease in the hope to identify patients at increased risk for stroke. METHODS: In 33 patients with intracranial internal carotid (n = 12), middle cerebral (n = 18), posterior cerebral (n = 2), or basilar artery stenosis (n = 1), we performed a 1-hour microembolus detection downstream to the stenosis in the middle or in the posterior cerebral artery, respectively. The stenosis was assessed by transcranial Doppler and duplex ultrasound. 18 patients had been symptomatic in the dependent territory. RESULTS: Five patients with ischaemic symptoms within the last 8 days and with a peak systolic flow velocity of > or =210 cm/s in the stenosis showed microembolic signals at a rate of 3-25 events/h, despite effective anticoagulation. All these 5 patients had a lesion pattern on cranial CT or MRI scan suggesting embolic origin. All the asymptomatic patients (n = 15) and all the patients with a peak systolic intrastenostic velocity of 160 to <210 cm/s (n = 13) did not show microembolic signals at all. CONCLUSION: Microembolic signals occur in recently symptomatic patients with high-grade intracranial arterial stenosis indicated by a sonographically measured stenotic peak flow velocity of > or =210 cm/s. Therapeutic anticoagulation was not sufficient to suppress microemboli formation.     

Mechanisms of single and multiple borderzone infarct: transcranial Doppler ultrasound/magnetic resonance imaging correlates

BACKGROUND AND PURPOSE: Hemodynamic patterns after borderzone (BZ) infarction are variable and dynamic. However, stroke mechanisms in different types of BZ infarctions have not been systematically studied by magnetic resonance angiography (MRA) and transcranial Doppler ultrasonography (TCD). METHODS: Forty-nine patients who experienced a stroke limited to the territory of either the superficial or internal borderzone proved on MRI included in our registry, corresponding to 4% of 1,200 patients with ischemic stroke, were studied. All these patients underwent MRA, extracranial Doppler ultrasonography, TCD and other investigations from the standard protocol of our registry. Twenty of them (41%) had a posterior BZ infarct, 14 (29%) an anterior BZ infarct, 10 (20%) a subcortical BZ infarct and 5 (10%) bilateral BZ infarcts. RESULTS: Unilateral internal carotid artery (ICA) tight stenosis or occlusion ipsilateral to the lesion was present in 14 patients (70%) with a posterior BZ infarct, in 72% of those with an anterior BZ infarct, in 80% of those with a subcortical BZ infarct and in 80% of those with bilateral BZ infarcts. TCD showed cross-filling of the middle cerebral artery via the anterior communicating artery in 5 patients (25%) with a posterior BZ infarct and 10% had an increased mean flow velocity (MFV) in the ipsilateral P1 posterior cerebral artery (PCA). In patients with an anterior BZ infarct, 3 (23%) had an MFV increase in the contralateral A1 anterior cerebral artery (ACA), and 2 (15%) had a higher MFV in the ipsilateral PCA. An elevated velocity at midline depths with reversed A1 ACA flow direction was seen in 2 patients (20%) with a subcortical infarct, and 1 patient (10%) had an MFV increase in the ipsilateral P1 PCA. Left ventricular systolic dysfunction (ejection fraction <40%) was present in 50% of patients with a posterior BZ infarct, in 36% of those with an anterior BZ infarct, in 20% of those with a subcortical BZ infarct and bilateral BZ infarcts each. CONCLUSION: The association of severe ICA stenosis or occlusion with cardiopathies and left ventricular dysfunction may play a critical role in those with BZ infarcts having inadequate collateral supply, while a cardioembolism or acute ICA dissection may also cause BZ infarction due to the rapidity of the occlusive process and the inability of the cerebral vasculature to recruit collateral pathways quickly enough.     

临床特征、影像和血管病变分型对脑梗死预后的预测

目的比较牛津地区卒中计划（Oxfordshire Community Stroke Project，OCSP）、影像和血管病变3种分型方法对脑梗死患者预后估计的差异。方法选取2000年1月至2002年5月在北京协和医院神经科住院治疗的脑梗死患者，根据OCSP分型将患者分为腔隙性梗死（LACI）、完全前循环梗死（TACI）、部分前循环（PACI）和后循环梗死（POCI）4种亚型。根据头部MRI所示脑梗死部位，将患者分为皮质、基底节区、放射冠和后循环梗死四种亚型。应用数字减影血管造影、磁共振血管成像、颈部血管彩超和脑血管造影评价患者的血管病变，并参考TOAST（Trial of Org 10172 in Acute Stroke Treatment）分型原则将患者分为大血管病变和小血管病变两型。应用Barthel指数（BI）和Rankin评分（Rs）了解不同亚型患者病后1年的功能状态，应用Kaplan—Meier法计算累积生存概率，评价不同亚型患者复发和死亡事件发生的差异。结果在调整各项危险因素后，OCSP分型与病后1年时的BI（P=0．004）、RS（P=0．004）显著相关，如加入病灶大小进行调整后，OCSP分型与BI和RS均无显著相关（P〉0．05），而与病灶大小显著相关（P=0．001）。影像分型与病后1年时的BI、Rs显著相关（P〈0．05），如加入病灶大小进行调整后，影像分型仍与BI、RS显著相关（P〈0．05）。OCSP和影像各亚型患者的复发和死亡事件差异无显著意义（P=0．76，P=0．51）。小血管病变患者复发和死亡事件的发生显著低于大血管病变（0 VS 17．9％，P=0．03）。结论不同分类方法对脑梗死预后的预测作用存在差异。     

不同脑梗死亚型患者血清Fractalkine浓度的差异

目的：探讨不同牛津郡社区卒中项目（OCSP）亚型急性脑梗死患者血清Fractalkine（FKN）浓度的变化。方法：45例急性脑梗死患者按OCSP分型分为完全前循环梗死（TACI）组、部分前循环梗死（PACI）组、后循环梗死（POCI）组和腔隙性梗死（LACI）组。采用酶联免疫吸附法检测发病1～3d、7d、14d和28d时血清FKN浓度，比较各组间的差异。分析FKN浓度与相应时间点美国国立卫生研究院卒中量表（NIHSS）评分和3个月时Barthel指数（BI）的相关性。结果：各种亚型急性脑梗死患者血清FKN浓度均升高，TACI组最为显著；在不同时间点，血清FKN浓度变化大致为TACI〉PACI〉LACI〉POCI，与相应时间点NIHSS评分呈正相关，与3个月时BI呈负相关。结论：血清FKN浓度的变化可能提示急性脑梗死各OCSP亚型患者炎症损伤的差异，并影响神经功能缺损程度和患者3个月时的转归。     

Combined carotid and transcranial ultrasound findings compared with clinical classification and stroke severity in acute ischemic stroke

BACKGROUND: The aim of this study was to assess the association between cerebral hemodynamics and the clinical picture as defined by the Oxfordshire Community Stroke Project (OCSP) classification, as well as the clinical severity as defined by the National Institute of Health Stroke Scale (NIHSS) within the first 6 h of an acute middle cerebral artery (MCA) stroke onset. METHODS: 70 unselected patients were grouped according to the OCSP classification and NIHSS. All patients immediately had extracranial and transcranial Doppler (TCD) ultrasound examinations. RESULTS: In the study population as a whole, there was a significant association between intracranial vascular pathology and the OCSP classification (p<0.001) as well as the NIHSS score (p<0.001). In patients with severe stroke, however, TCD demonstrated the hypothesized proximal MCA(1) occlusion in only 34% of patients with an OCSP-defined total anterior circulation syndrome and in 42% of patients with an NIHSS score of >or=15. In moderate stroke, the OCSP classification was misleading in almost half of the patients with a partial anterior circulation syndrome, i.e. a hypothesized distal MCA(2) occlusion suitable for thrombolysis. CONCLUSIONS: Neither the OCSP classification nor the NIHSS grading provided reliable information about the site or presence of intracranial arterial occlusion in acute stroke within the first 6 h after stroke onset in the individual patient. The results of this study strongly suggest that selection of acute ischemic stroke patients for thrombolysis should also include an assessment of cerebral hemodynamics.     

Relationship between subtypes of MRI-confirmed acute ischemic stroke based on OCSP and TOAST classifications

BACKGROUND： Two classification systems exist for subtypes of acute cerebral infarction. One was developed for the Trial of Org 10172 in Acute Stroke Treatment （TOAST）, based primarily on etiology. The other is the Oxfordshire Community Stroke Project （OCSP）, based on clinical features.
OBJECTIVE： To evaluate the relationship between OCSP and TOAST classifications in terms of stroke location and etiology in 126 patients with acute ischemic stroke confirmed by transcranial magnetic resonance imaging （MRI）.
DESIGN, TIME AND SETTING： Retrospective case analysis. Transcranial MRI, diffusion weighted imaging, and magnetic resonance angiography were performed in 126 patients with acute stroke during the first 48 hours following admission to the Department of Neurology, Navy General Hospital of Chinese PLA.
PARTICIPANTS： A total of 126 patients with acute stroke, comprised of 71 males and 55 females, admitted to the Navy General Hospital of Chinese PLA between December 2005 and April 2006 were included.
METHODS： Of 126 patients with acute stroke, 13 exhibited total anterior circulation infarcts （TACI）, 51 had partial anterior circulation infarcts （PACI）, 28 suffered posterior circulation infarcts （POCI）, and 34 had lacunar infarcts （LACI） based on OCSP classification. However, according to TOAST classification, 19 cases were a result of large-artery atherosclerosis, 32 by cardioembolism, 36 by small-vessel occlusion, 1 by stroke of other determined etiology, and 38 by stroke of undetermined etiology.
MAIN OUTCOME MEASURES： The corresponding relationship of the subtypes of acute stroke based on OCSP and TOAST.
RESULTS： Of patients with TACI, 8 （61.5%） were caused by cardioembolism. Of patients with PACI, 16 （31.4%） were caused by large-artery atherosclerosis and 17 （33.3%） by cardioembolism. Of patients with POCI, 12 （42.8%） were a result of small-vessel occlusion. Of patients with LACI, 17 （50.0%） were caused by hypertension and arteriolar sclerosi     

Intracranial large artery disease among OCSP subtypes in ethnic South Asian ischemic stroke patients

The site of vascular stenosis correlates well with the Oxfordshire Community Stroke Project (OCSP) classification among Caucasians, but not among ethnic Chinese patients. We prospectively studied 205 consecutive ethnic South Asian ischemic stroke patients to investigate the prevalence of intracranial large artery disease determined by transcranial color-coded doppler and magnetic resonance angiography among OCSP subtypes. The distribution of OCSP subtypes was 7% total anterior circulation infarction (TACI), 17% partial anterior circulation infarction (PACI), 14% posterior circulation infarction (POCI) and 62% lacunar infarction (LACI). Significant intracranial large artery disease was common among all OCSP subtypes; 79% with TACI, 47% PACI, 65% POCI and 44% LACI. This is similar to ethnic Chinese data and is likely due to the predominance of intracranial disease over extracranial disease. Clinical axioms using OSCP subtypes based on Caucasian data may be misleading if applied to ethnic South Asians.     

缺血性脑卒中OCSP分型与神经影像学及脑血管改变之间的关系

目的以OCSP分型为基础,结合影像学和DSA表现探讨缺血性卒中OCSP分型、神经影像学改变、血管改变之间的关系。方法回顾性分析227例经DSA证实存在血管狭窄患者的临床资料,据患者主要症状和体征、MRI、CT、DSA的结果进行OCSP分型、影像学分型、及血管病变部位分型。分析OCSP分型与神经影像学及脑血管改变之间的关系。结果 OCSP各型所占的比例依次为:(1)部分前循环梗死型(PACI)占47%;后循环梗死型(POCI)占31%;完全前循环梗死型(TACI)占13%;腔隙性梗死型LACI占9%。(2)OCSP分型中前循环梗死型(TACI+PACI)、腔隙性梗死型(LACI)、后循环梗死型(PCI)与影像学分型中皮质梗死和低灌流区梗死(CO+LFI)、皮质下小梗死(SSI)、后循环病变部位梗死(PCI)的一致率分别为77.97%、79.30%、79.30%。(3)OCSP分型中前循环型(TACI+PACI)和后循环型(POCI)与前循环血管狭窄(ICA+MCA)和后循环血管狭窄(VA+BA)一致率分别为78.41%、71.84%。结论 OCSP分型与神经影像学改变分型和血管改变分型的一致性较好。     

大脑中动脉粥样硬化的狭窄度与卒中机制——一项高分辨磁共振研究

目的本研究旨在探索大脑中脉(middle cerebral artery,MCA)狭窄率与MCA斑块形态学及梗死类型的相关性,并探索不同狭窄率患者卒中的发生机制。方法连续收集2009-2014年于北京协和医院就诊的2周内发生MCA供血区缺血性卒中并进行高分辨磁共振(high-resolution magnetic resonance imaging,HRMRI)扫描的患者。纳入MCA M1段存在斑块的患者,排除心源性、颅外大动脉粥样硬化及其他病因的卒中患者。在弥散加权成像(diffusion weighted imaging,DWI)上将梗死类型分为穿支、皮层、分水岭和混合型梗死,并测量梗死体积。在矢状位HRMRI上测量MCA M1段狭窄率,并收集斑块位置、长度、厚度、信号和斑块连续性等形态学指标。将狭窄率50%的患者分入重度狭窄组,将狭窄率≤50%的患者归入轻度狭窄组。结果研究共纳入102例患者,其中重度狭窄组39例,轻度狭窄组63例。重度狭窄组患者卒中,穿支梗死14例(35.9%),皮层梗死9例(23.1%),分水岭梗死4例(10.3%),混合型梗死12例(30.8%);轻度狭窄组患者中,穿支梗死44例(69.8%),皮层梗死8例(12.7%),分水岭梗死3例(5.8%),混合型梗死8例(12.7%),两组构成类型比较,差异有显著性(P=0.014)。与轻度狭窄组比较,重度狭窄组患者斑块更长(P0.001)、更厚(P0.001)、更多混合信号斑块(P0.001)。斑块厚度(P0.001,OR 87.792,95%CI 13.120~587.453)和斑块混合信号(P=0.007,OR 7.358,95%CI 1.725~31.382)是MCA狭窄率50%的独立预测因子。重度狭窄组中,梗死体积与斑块表面不连续(P=0.004)相关。轻度狭窄组中,梗死类型与斑块表面不连续(P=0.002)及斑块厚度(P=0.032)相关。且斑块表面不连续是发生栓塞性梗死的独立预测因子(P=0.003,OR 5.778,95%CI 1.788~18.672)。结论 MCA狭窄率50%和≤50%的患者具有不同的卒中分型比例和斑块形态学;狭窄率≤50%的斑块表面不连续是栓塞性梗死独立预测因子,提示轻度狭窄MCA斑块破裂可能是引起栓塞性病灶的机制。     

Three-dimensional transcranial Doppler blood flow mapping in patients with cerebrovascular disorders

We investigated 60 patients with cerebrovascular disorders using a three-dimensional transcranial Doppler blood flow mapping system. A composite display of the circle of Willis is created with computer assistance, allowing accurate vessel identification and optimal data documentation of blood flow velocity and direction in the basal cerebral arteries. The basilar artery was insonated in every patient; the middle cerebral artery and the most distal internal carotid artery were found in 95% of the patients, the anterior cerebral artery in 85%, and the posterior cerebral artery in 84%. Insonation problems occurred predominantly in elderly women. Transcranial Doppler blood flow mapping showed an abnormal result in 23 of 60 patients (38%). An intracranial stenosis with greater than 50% diameter reduction or occlusion was found in 10 of 31 patients (32%) with completed stroke, reversible ischemic neurologic deficit, or transient ischemic attack. Collateral blood flow mechanisms could be demonstrated in patients with extracranial carotid artery occlusions. Intra-arterial cerebral angiography performed in 21 patients confirmed the transcranial Doppler blood flow mapping diagnosis in 19 (90.5%). In one patient an arteriovenous malformation diagnosed by transcranial Doppler blood flow mapping was confirmed by magnetic resonance imaging.     

单侧颈内动脉狭窄或闭塞的影像学梗死类型及脑血流动力学评价

目的研究单侧动脉粥样硬化性颈内动脉狭窄或闭塞(ICASO)性脑梗死患者影像学梗死类型及其脑血流动力学改变,以探讨脑梗死发生的可能机制。方法 87例经脑血管造影明确诊断的单侧动脉粥样硬化性ICASO性脑梗死患者,MRI和TCD检查分析影像学梗死类型及不同类型之间存在的脑血流动力学差异。结果 MRI所见脑梗死类型共分为区域梗死(30例,34.48%)、皮质下梗死(27例,31.03%)、边缘带梗死(18例,20.69%)和弥散小梗死(12例,13.79%),不同脑梗死类型发生率之间差异具有统计学意义(χ~2=7.156,P=0.028);脑梗死类型与颈内动脉狭窄程度呈负相关(r=-0.275,P=0.010),重度狭窄以皮质下梗死、边缘带梗死多见(均11/36,30.56%),完全闭塞则以区域梗死常见(17/34,50.00%)。脑血流动力学观察显示,不同脑梗死类型患侧大脑中动脉平均血流速度和搏动指数与健侧存在明显的不对称性(均P=0.000),其中以区域梗死最低,次之为边缘带梗死。结论 ICASO以区域梗死多见,且脑血流动力学障碍存在于各种脑梗死类型中。提示应综合考虑脑梗死类型和脑血流动力学改变,从而选择恰当的防治方法。     

Significance of hyperintense vessels on FLAIR MRI in acute stroke

OBJECTIVE: To describe hyperintense vessels sign (HVS) in patients with acute stroke on fluid-attenuated inversion recovery (FLAIR) MRI and determine its clinical significance and utility. BACKGROUND: Enhancement of vessels on postcontrast MRI in patients with acute stroke is considered an indicator of early brain ischemia. Recently, the FLAIR technique has shown promise in earlier and better detection of ischemic brain parenchymal lesions. METHODS: Two observers retrospectively reviewed 304 MRI of patients with stroke and identified 30 patients with acute middle cerebral artery stroke and HVS on FLAIR obtained within 24 hours of symptom onset. These patients were evaluated with contrast-enhanced MRI (n = 9), MR angiography of carotid and intracranial circulation (n = 30), cerebral angiography (n = 8), transcranial Doppler (n = 17), and SPECT (n = 16). The extent of HVS was compared with final infarct size and NIH Stroke Scale score. RESULTS: HVS on FLAIR was seen in 10% of the patients with acute stroke. HVS was associated with large vessel occlusion or severe stenosis (>90%). Intravascular enhancement on contrast MRI was observed in vessels that were hyperintense on FLAIR. Both cortical and subcortical infarcts demonstrated HVS. MR angiographic and cerebral angiographic findings of large vessel occlusion or severe stenosis (>90%), slow flow, low velocities by transcranial Doppler, and hypoperfusion on SPECT correlated with HVS. HVS was the earliest ischemic change in three patients scanned within 3 hours of ictus. Final infarct size was smaller than the area showing HVS in all patients. CONCLUSION: HVS on FLAIR MRI is an indicator of slow flow and early ischemia as a result of large vessel occlusion or stenosis and inadequacy of collateral circulation. HVS does not mean that infarction has occurred but indicates brain tissue at risk of infarction. It should prompt consideration of revascularization and flow augmentation strategies.     

Intracranial clot dissolution is associated with embolic signals on transcranial Doppler.

Reperfusion of intracranial arteries can be detected by transcranial Doppler (TCD). The authors report microembolic signals (MES) on TCD as a sign of clot dissolution and recanalization. Microembolic signals were detected during routine diagnostic TCD examination performed in the emergency room in patients eligible for thrombolytic therapy. Microembolic signals were found at the site of M1 middle cerebral artery (MCA) high-grade stenosis or near-occlusion. Transcranial Doppler was performed before, during, and after thrombolytic therapy. Of 16 consecutive patients, 3 (19%) had MES on TCD. All three patients had a severe MCA syndrome at 2 hours after stroke onset scored using the National Institutes of Health Stroke Scale (NIHSS). In patient #1 (NIHSS 12), clusters of MES were detected distal to a high-grade M1 MCA stenosis preceding spontaneous clinical recovery by 2 minutes. Because of subsequent fluctuating clinical deficit, intraarterial thrombolysis was given with complete recovery. In patient #2 (NIHSS 20), TCD detected an M1 MCA near-occlusion. At 1.5 hours after intravenous tissue plasminogen activator, TCD showed minimal MCA flow signals followed by MES, increased velocities, and normal flow signals in just 2 minutes. She gradually recovered up to NIHSS 8 in 5 days. In patient #3 with NIHSS 22 and an M1 MCA near-occlusion, TCD detected MES 15 minutes after TPA bolus followed by MCA flow velocity improvement from 15 cm/sec to 30 cm/sec. The patient recovered completely by the end of tissue plasminogen activator infusion. The authors conclude that embolic signals detected by TCD at the site of arterial obstruction can indicate clot dissolution. Intracranial recanalization on TCD can be associated with MES and changes in flow waveform, pulsatility, and velocity if insonation is performed at the site of arterial obstruction.     

Carotid artery stenosis in ischemic stroke patients with nonvalvular atrial fibrillation.

PURPOSE: To study the prevalence, severity and clinical relevance of carotid atherosclerosis in ischemic stroke patients with nonvalvular atrial fibrillation (NVAF). MATERIAL AND METHODS: We reviewed carotid duplex sonography, computed tomography (CT) and clinical features in 103 consecutive ischemic stroke patients with NVAF. Both sonography and CT were performed within 3-7 days after stroke. There were 64 men and 39 women with a mean age at stroke onset of 69 years. RESULTS: High-grade (> or =50%) stenosis of the extracranial carotid artery was detected in 25 patients (24.3%), including 11 patients (10.6%) with internal carotid artery (ICA) occlusion. In 15 (66.7%) of the patients who had high-grade carotid stenosis, the lesion was ipsilateral to the infarct, including 8 ICA occlusions. Patients with high-grade stenosis smoked more cigarettes (p < 0.05) and had more peripheral vascular diseases (p < 0.05). Besides NVAF, all patients had more than one vascular risk factor. The clinical presentations (transient ischemic attacks, minor or major strokes) showed no significant difference between the groups of <50% and > or =50% stenosis. Clinical outcome was worse (dead and totally dependent in daily activities) in the group of high-grade stenosis (p < 0.05). Patients with high-grade carotid stenosis showed more cortical infarcts on cerebral CT (p < 0.01). Six out of 7 patients with a hemorrhagic transformation on the initial cerebral CT were in the low-grade carotid stenosis group, though this was statistically insignificant. CONCLUSIONS: Ischemic stroke with NVAF is not always cardiogenic. High-grade stenosis of the extracranial carotid artery is found in one fourth of ischemic stroke patients with NVAF and is related to more cortical infarction and worse clinical outcome. We speculate that ischemic stroke patients with NVAF who have high-grade carotid stenosis are less likely to develop hemorrhagic infarct. The pathogenesis of cerebral infarction and the therapeutic strategy in this clinical condition are complicated by the coexistence of carotid arterial lesions and cardiac disease.     

2型糖尿病患者无症状的大脑中动脉狭窄的危险因素分析

目的 探讨住院2型糖尿病患者无症状大脑中动脉（MCA）狭窄的相关危险因素。方法回顾性总结227例2型糖尿病住院患者的病历资料，排除合并中风或中风史以及其他颅内疾病患者。用TCD诊断MCA狭窄。结果227例患者中MCA狭窄者共61例，狭窄率（26．9％），狭窄组病人年龄、病程、收缩压、尿酸水平、合并高血压和心电图异常率明显高于非狭窄组；Logistic回归分析显示糖尿病病人的病程以及合并高血压是无症状颅内动脉狭窄的独立危险因素。结论糖尿病病程延长及合并高血压是无症状MCA狭窄的独立危险因素。     

The validity of a simple clinical classification of acute ischaemic stroke

The aim of the study reported here was to test the validity of a simple clinical classification of acute ischaemic stroke (Oxfordshire Community Stroke Project, OCSP) in predicting the site and size of cerebral infarction on computed tomography (CT). Consecutive patients admitted to hospital with acute ischaemic stroke were prospectively identified and classified into one of four clinical syndromes according to the OCSP classification, blind to the result of CT. The CT brain scans were classified blind to the clinical features into those demonstrating: small, medium or large cortical infarcts; small or large subcortical infarcts in the anterior circulation territory; and posterior cerebral circulation territory infarcts. A total of 108 patients were included. A recent infarct was seen. on the CT scan in 91 patients (84%), and the clinical classification correctly predicted the site and size of the cerebral infarct in 80 of these (88%; 95% confidence interval 77–92%). The positive predictive value was best for large cortical infarcts (0.94) and worst for small subcortical infarcts (0.63). The OCSP clinical classification is a reasonably valid way of predicting the site and size of cerebral infarction on CT and can, therefore, be used very early after stroke onset before the infarct appears on the scan.     

How well does the Oxfordshire Community Stroke Project classification predict the site and size of the infarct on brain imaging?

OBJECTIVES: The Oxfordshire Community Stroke Project (OCSP) classification is a simple clinical scheme for subdividing first ever acute stroke. Several small studies have shown that when an infarct is visible on CT or MRI, the classification predicts its site in about three quarters of patients. The aim was to further investigate this relation in a much larger cohort of patients in hospital with ischaemic stroke. METHODS: Between 1994 and 1997, inpatients and outpatients with ischaemic stroke were assessed by one of several stroke physicians who noted the OCSP classification. A neuroradiologist classified the site and extent of recent infarction on CT or MRI. RESULTS: Of 1012 patients with ischaemic stroke, 655 (65%) had recent visible infarcts. These radiological lesions were appropriate to the clinical classification in 69/87 (79%) patients with a total anterior circulation syndrome, 213/298 (71%) with a partial anterior circulation syndrome, 105/144 (73%) with a lacunar syndrome, and 105/126 (83%) with a posterior circulation syndrome. Overall, 75% of patients with visible infarcts were correctly classified clinically. If patients without a visible infarct did have an appropriate lesion in the brain (best case), the classification would have correctly predicted its site and size in 849/1012 (84%) patients, compared with only 492/1012 (49%) in the worst case scenario. CONCLUSION: The OCSP classification predicted the site of infarct in three quarters of patients. When an infarct is visible on brain imaging, the site of the infarct should guide the use of further investigations, but if an infarct is not seen, the OCSP classification could be used to predict its likely size and site.     

Clinical implication of cerebral artery calcification on brain CT

BACKGROUND AND PURPOSE: Arterial calcification is a process of atherosclerosis, usually taking place within advanced atheromatous plaque. In the coronary arteries, calcification seen on computed tomography (CT) often indicates severe stenosis, and is noted in almost all patients with coronary symptoms. Calcification of the cerebral arteries is also frequently observed on brain CT, but its clinical significance has yet to be clarified. To evaluate the clinical significance of cerebral arterial calcification on brain CT, we investigated the angiographic and transcranial Doppler ultrasonography (TCD) findings of calcified cerebral arteries. METHODS: The subjects were 57 patients with ischemic stroke, all of whom underwent brain CT, digital subtraction cerebral angiography and TCD. Stroke subtypes were defined according to TOAST classification. Two clinicians who were blinded in respect to the patients' clinical history and to each other's interpretation, determined the presence of cerebral arterial calcification and the degree of angiographic stenosis. RESULTS: Cerebral artery calcification was noted in 23 patients (40%) out of a total of 46 arteries, consisting of 23 internal carotid, 15 vertebral, 5 basilar, 2 middle cerebral and 1 anterior cerebral artery. The patients with calcification were significantly older and more hypertensive than those without calcification. All the patients with calcification showed either large artery atherosclerosis or lacunar stroke. Hemodynamic alterations measured by TCD were rarely observed in calcified arteries. The severity and extent of the atherosclerotic changes were significantly greater in the patients with calcification than those without calcification. CONCLUSION: These results suggest that cerebral arterial calcification does not directly indicate hemodynamically significant atherosclerotic stenosis involving calcified segments, but indicates the underlying etiology of either large artery atherosclerosis or lacunar stroke, and raises the possibility of a diffuse atherosclerotic process being present in the cerebral circulation.     

Three-dimensional transcranial Doppler in acute ischemic stroke in the territory of the middle cerebral artery: Clinical and CT correlation

We studied 34 patients with acute ischeiic stroke in the territory of the middle cerebral artery (MCA) by three-dimensional transcranial Doppler (TCD-3D). The parameters analyzed were: mean blood flow velocity, systolic and diastolic velocities; indices of pulsatility, hemisphere asymmetry and pulsatility transmission. Of the 34 patients 11 presented marked slowing of flow velocity in the MCA on the infarct side with an asymmetry index (AI) of over 40%, 8 patients with slightly reduced flow velocity in the MCA and an AI of 25–40%, 2 patients in whom there was indirect evidence of collateral circulations in the anterior cerebral artery distribution together with slowing of MCA flow; 5 patients had stenosis of the MCA, 9 patients showed no alterations of the Doppler parameters. The correlation between neurological symptom pattern and AI was significant (r=0.76). Noninvasive, easy to perform, performable at once and reliable, TCD-3D is a great improvement on traditional transcranial Doppler and is especially useful in assessing the hemodynamics of the cerebral circulation in ischemic stroke.