多发性硬化与视神经脊髓炎谱系疾病的OCT评价

目的利用OCT检测MS与NMOSD患者黄斑区神经节细胞复合体(ganglion cell complex,GCC)和视网膜神经纤维层(retinal nerve fiber layer,RNFL)厚度,对其所致的视神经及轴突损伤进行分析。方法采用回顾性对照研究方法。收集河南科技大学第一附属医院治疗的MS患者30例为MS组,NMOSD患者32例为NMOSD组,同期健康受试者30例为对照组。采用OCT检测GCC(上、下象限和平均)和RNFL(鼻、颞、上、下4个象限及平均)的厚度,并进行比较分析。结果 NMOSD组和MS组GCC厚度(上、下象限和平均)及RNFL(4个象限和平均)厚度均显著低于对照组(P0.05)。NMOSD组上、下象限及平均GCC厚度低于MS组(P0.05)。NMOSD组上方RNFL厚度低于MS组(P0.05),但鼻、颞及下方象限RNFL厚度与MS组差异无统计学意义(P0.05)。结论 MS和NMOSD患者均存在明显的视神经及轴突损伤,但NMOSD患者损伤更为明显。     

慢性脑缺血小鼠脑血管形态学变化的活体动态观察

目的 通过建立慢性脑缺血模型,活体动态观察慢性脑缺血后小鼠脑血管形态学变化。 方法 Tie2-GFP转基因小鼠7只,左侧颈总动脉永久性结扎结合右侧颈总动脉短暂结扎方法制备慢 性脑缺血模型,分别在脑缺血前（D0)和脑缺血后7 d（D7）,利用颅窗和激光共聚焦显微镜活体观察 小鼠脑缺血前后皮层毛细血管、细动脉及细静脉的变化情况。 结果 ①缺血前和脑缺血后7 d毛细血管直径分别是（6.62±0.75）μm和（12.50±3.29）μm,脑 缺血后毛细血管直径较缺血前扩张（P＜0.001）;②脑缺血前和脑缺血后7 d毛细血管密度分别为 每感兴趣区域（region of interest,ROI）（11.67±1.72）个和每RO（I 11.08±2.06）个,差异无显著性 （P =0.0583）;③脑缺血前和脑缺血后7 d分支毛细血管、网状毛细血管、集合毛细血管及细动静脉直 通支直径分别为（6.33±0.94）μm vs （12.36±3.20）μm,（6.87±1.10）μm vs （12.37±2.78）μm, （6.37±0.52）μm vs （11.41±3.10）μm及（6.35±0.92）μm vs （13.91±6.17）μm,脑缺血后均扩张 （P分别为＜0.01,＜0.01,＜0.01及＜0.05）,其中细动静脉直通支扩张最显著;④细静脉直径在D0 和D7时分别为（19.59±8.74）μm和（24.81±6.25）μm,脑缺血后细静脉显著扩张（P =0.0054）;而 细动脉直径在D0和D7时分别是（12.71±2.10）μm和（13.20±3.09）μm,无显著性改变（P =0.2947）; ⑤可见细动静脉迂曲、吻合支开放及毛细血管走行改变等血管重构现象。 结论 慢性脑缺血后皮层血管发生毛细血管扩张、细静脉扩张等改变,这些改变可能有助于调节脑 血流量。     

光相干连续断层成像术在视神经脊髓炎谱系病的临床应用

目的探讨光相干连续断层成像术(OCT)在视神经脊髓炎谱系病(NMOSD)的临床应用。方法利用OCT对49例NMOSD患者(NMOSD组)和1 5例健康对照志愿者(对照组)视乳头周围视网膜神经纤维层(RNFL)厚度进行比较;NMOSD组再根据是否伴视神经炎、水通道蛋白抗体状态(AQP4-IgG)等对NMOSD组分为伴视神经炎(NMOSD-ON)亚组(34例);不伴视神经炎(NMOSD-NON)亚组(15例)。比较各亚组的RNFL厚度差异;采用扩展病残状态评分(EDSS)评价神经功能缺损程度,分析EDSS与RNFL是否存在相关性。结果 NMOSD患者受累眼的RNFL各象限厚度与未受累眼和对照组比较显著变薄(P0.01);NMOSD未受累眼与对照组比较,RNFL厚度差异无显著性(P0.05)。AQP4-IgG阳性或阴性NMOSD-ON亚组的RNFL厚度比较差异无显著性(P0.05);RNFL厚度变化与NMOSD残障的严重程度无相关性(P0.05)。结论 RNFL变薄仅在NMOSD受累眼表现,厚度变化与AQP4-IgG无关,OCT可能有助于临床对NMOSD诊疗提供参考指标。     

帕金森病伴糖尿病患者视网膜功能变化及灯盏花素干预效果观察

目的观察帕金森病伴糖尿病患者视网膜功能变化及灯盏花素的干预效果。方法以我院2013-05—2014-05收治的56例(112只眼)帕金森病伴糖尿病患者为研究对象,将其设为观察组;另选取我院同期健康体检者56例(112只眼)为对照组,患者均采用光学相干断层扫描技术(OCT)行视网膜神经纤维层(RNFL)与黄斑区视网膜检查,统计2组患者RNFL厚度、黄斑厚度,记录视野平均缺损深度(MD)。随机将观察组分为A组(28例,56眼)和B组(28例,56眼),A组仅接受原发性疾病内科治疗,B组给予灯盏花素进行干预,3个月后再次检测2组患者上述指标。结果观察组患者平均RNFL厚度(125.53±19.53)μm、黄斑平均厚度(276.05±8.44)μm及MD值(-5.13±1.96)dB均显著低于对照组[(136.53±22.93)μm、(286.93±13.69)μm及(-0.53±2.47)dB],2组间差异有统计学意义(P0.05);3个月后,B组上述指标均优于对照组,2组间对比差异有统计学意义(P0.05)。结论帕金森病伴糖尿病患者视网膜神经纤维层厚度、黄斑厚度较正常人明显变薄,使用灯盏花素进行干预可获得理想效果,改善视功能,适合于临床推广。     

症状性和无症状性颈内动脉狭窄的大脑中动脉微栓子信号监测

目的观察症状性和无症状性颈内动脉狭窄的患者大脑中动脉微栓子信号（microembolicsig-nals,MES）阳性率及MES计数的变化,研究微栓子与临床症状和颈内动脉狭窄程度的关系。方法选取症状性颈内动脉狭窄患者26例,无症状性颈内动脉狭窄患者20例及正常对照组30例;症状性颈内动脉狭窄组又分为短暂性脑缺血发作（transient ischemic attack,TIA）组（12例）和脑梗死组（14例）;症状性和无症状性颈内动脉狭窄的患者均行DSA或CTA检查,并对颈内动脉狭窄程度进行分级;所有颈内动脉狭窄的患者均对颈内动脉狭窄同侧的大脑中动脉进行MES监测,正常对照组则对双侧大脑中动脉进行MES监测。结果有症状和无症状颈内动脉狭窄组的MES阳性率高于正常对照组（P〈0．01）;有症状颈内动脉狭窄组MES阳性率较无症状组高（P〈0．05）;TIA组和脑梗死组比较,MEs阳性率无显著性差异（P〉0．05）;症状性和无症状性颈内动脉狭窄患者,轻、中、重度狭窄三组的MES阳性率比较均有显著性差异（P〈0．05）;MES阳性患者MES计数与颈内动脉狭窄程度呈正相关（r=0．9155,P〈0．01）。结论MES多见在颈内动脉狭窄患者,特别是症状性颈内动脉狭窄的患者,是缺血性脑血管疾病发生的高危因素。     

短暂性脑缺血发作患者血浆高半胱氨酸与尿酸水平相关性研究

目的 探究短暂性脑缺血发作（transient i schemic a ttack,TIA）患者血浆同型半胱氨酸（homocysteine, HCY）和尿酸（uric acid,UA）的水平及二者的相关性。 方法 收集110例TIA患者及115例健康查体者血液标本,分别采用荧光免疫法、比色法测定血浆HCY、 UA的水平。 结果 TIA组血浆HCY和UA浓度分别为（20.47±7.32）μmol/L和（341.17±84.31）μmol/L;对照组血 浆HCY和UA浓度分别为（15.28±4.62）μmol/L和（298.67±64.59）μmol/L。TIA组患者HCY、UA表达显 著高于对照组（均P＜0.001）。Pearson相关分析示TIA组HCY、UA二者呈正相关（r =0.239,P =0.012）。 Logistic回归分析示,尿酸[比值比（odds ratio,OR）1.017,95%可信区间（confidence interval,CI） 1.012～1.023,P <0.001]、HCY（OR 1.077,95%CI 1.003～1.156,P =0.041）为TI A危险因素。 结论 TIA患者血浆HCY、UA水平均增高且二者具有相关性。     

视神经脊髓炎与复发缓解型多发性硬化患者视网膜神经纤维层厚度的对比研究

目的检测视神经脊髓炎（NMO）与复发缓解型多发性硬化（RRMS）患者的视神经纤维层（RNFL）厚度，从而分析NMO与RRMS的轴索损伤情况。方法采用光学相干断层成像（OCT）技术，检测NMO和RRMS患者的RNFL的厚度，并进行统计学分析。结果视神经受累的NMO与RRMS患者，其平均RNFL的厚度分别为：（71．41±22．88），（88．38±12．16）μm；其中以颞侧象限L（51．94±9．29），（69．50±18．02）μml和下象限[（90．59±40．77），（113．94±16．64）μml的RNFL减少更明显，差异具有统计学意义（P〈0．01）。结论NMO患者的平均RNFL厚度较RRMS薄，提示NMO患者的轴索损伤较RRMS为重，并且以颞侧象限和下侧象限的轴索损伤为明显。     

颈动脉迂曲与前循环动脉瘤形成的相关性研究

目的 探讨颈动脉迂曲与前循环动脉瘤形成的相关性。 方法 采用头颈部CTA检查测量2018年1-6月100例前循环动脉瘤住院患者与同期100例无颅内动 脉瘤住院患者的颈总动脉（common carotid artery,CCA）迂曲指数（tortuosity index,TI）、颈内动脉 （internal carotid artery,ICA）TI、颈动脉夹角（ICA角）等指标,来衡量颈动脉的迂曲程度。Pearson相关 分析CCA TI、ICA TI、ICA角与一般危险因素的关系,使用单因素及多因素逐步Logistic回归分析颈动脉 迂曲与前循环动脉瘤形成的关系。 结果 前循环动脉瘤组高脂血症病史（43% vs 58%,P =0.034）、缺血性卒中病史（39% vs 58%, P =0.007）比例低于对照组,而C CA TI（1.409±0.135 vs 1.352±0.137,P =0.004）、I CA TI （1.592±0.186 vs 1.523±0.149,P =0.005）、ICA角（46.450°±6.465°vs 44.303°±6.409°,P =0.016） 均高于对照组。前循环动脉瘤组CCA TI与冠心病病史正相关（r =0.220,P =0.027）,ICA TI与男性正相 关（r =0.244,P =0.025）。I CA TI（OR 4.694,95%CI 0.999～1.099,P =0.018）、I CA角（OR 1.052,95%CI 1.389～23.308,P =0.039）是前循环动脉瘤的独立危险因素,而缺血性卒中史患者较少发生动脉瘤 （OR 0.569,95%CI 0.313～1.017,P =0.045）。 结论 颈内动脉迂曲程度与男性相关,颈总动脉迂曲程度与冠心病病史相关,颈动脉迂曲程度是前 循环动脉瘤形成的独立危险因素,而缺血性卒中史患者较少发生动脉瘤。     

黄斑区视网膜及视盘周围神经纤维层厚度在帕金森病痴呆及非痴呆患者中的特点分析

目的通过Cirrus高分辨率光学相干断层扫描(Cirrus HD-OCT)分析帕金森病(PD)患者的黄斑视网膜厚度及视盘周围视网膜神经纤维层厚度(RNFL)变化特点,以及帕金森病黄斑区各象限视网膜厚度与简易精神状况量表(MMSE)、蒙特利尔认知评估量表(MoCA)总分、日常生活能力评定(ADL)及视空间与执行发生的相关性,并进一步探讨帕金森病痴呆组和非痴呆组的黄斑视网膜及视盘周围RNFL变化。方法选择2018年11月至2019年10月在山西医科大学第一医院神经内科确诊的帕金森病患者25例(50只眼)作为PD组,以及与之年龄、性别相匹配的健康者15例(30只眼)作为对照组,行HD-OCT检查,分析PD组和对照组间及PD非痴呆和痴呆组黄斑视网膜及视盘周围RNFL厚度变化,分析PD患者黄斑区各象限视网膜厚度与认知障碍之间的相关性。采用SPSS20.0统计学软件对两组受检者数据进行分析,以P 0.05为差异有统计学意义。结果 PD组与对照组相比,黄斑区外环上方(t=-2.105,P=0.035)、鼻侧(t=-2.140,P=0.036)、颞侧(t=-2.339,P=0.019)、内环鼻侧(t=-2.072,P=0.042)视网膜厚度差异均具有统计学意义。视盘周围各象限及平均视网膜厚度间差异无统计学意义(P 0.05)。PDD组与n-PDD组相比较,黄斑区外环颞侧与内环各象限(上、下、鼻、颞)视网膜差异有统计学意义(P 0.05),且PDD组黄斑区视网膜厚度较n-PDD组及对照组普遍变薄。PDD组与对照组相比,PDD组外环上方、颞侧及内环各象限(上、下、鼻、颞)视网膜厚度均较对照组差异有统计学意义(P 0.05)。其中内环上方、内环颞侧厚度对于帕金森病痴呆有较好的诊断价值,其受试者工作特征曲线下面积分别为71.4%(95%CI0.547～0.881)、74.7%(95%CI 0.582～0.911)。PDD组与n-PDD组比较,视盘颞侧神经纤维层厚度变薄,差异有统计学意义。结论帕金森病患者黄斑区视网膜厚度较对照组明显变薄,帕金森病痴呆组黄斑区视网膜厚度较非痴呆组及对照组明显变薄,其中内环上方、内环颞侧厚度对于帕金森病痴呆有较好的诊断价值。帕金森病痴呆组患者视盘颞侧神经纤维层厚度较非痴呆组及对照组明显变薄。     

光学相干断层扫描及血管造影在认知损害诊断中的应用及其影响因素分析

目的 探究基于光学相干断层扫描(OCT)及光学相干断层扫描血管造影(OCTA)技术的视网膜标志物在认知损害诊断中的应用，并分析其与人口学特征及共患病之间的关联性。方法 纳入来自上海记忆研究和上海老年研究的受试者374例，经临床诊断分为认知损害组和认知正常组，采集两组人口学及共患病信息，应用OCT及OCTA技术检测其视网膜厚度及血管指标，探索在认知损害诊断中人口学信息及共患病对视网膜标志物的影响。结果 认知损害组视网膜神经纤维层(RNFL)、神经节细胞复合体(GCC)、黄斑区视网膜全层及内层厚度和视网膜浅层及深层毛细血管丛的血管密度与认知正常组比较差异均有显著性(均P<0.05)。年龄对视网膜厚度及血管密度存在显著影响(r=-0.456～-0.123,P<0.05)，经校正性别后仍呈相关性(均P<0.05)。校正性别后，认知正常组视网膜血管密度、认知损害组视网膜厚度和浅层血管密度与年龄均呈相关性(均P<0.05)。女性与更薄的黄斑区视网膜厚度和更大的深层血管密度呈相关性(均P<0.05)；校正年龄后，认知正常组女性的黄斑区视网膜厚度显著更薄(r=-0.312...     

急性脑梗死散在和单一弥散加权成像病损与其供血动脉狭窄的关系

目的 探讨急性脑梗死弥散加权磁共振成像(DWI)上大脑中动脉(MCA)供血区散在性或单一性缺血性病损与其脑供血动脉狭窄或闭塞的关系.方法 回顾性分析73例连续积累的DWI显示一侧MCA供血区脑梗死的病例,入组病例均排除心源性栓塞性脑梗死,所有患者均在发病24 h内进行MRI和MRA等检查,7例患者并进行DSA.采用DWI急性缺血性病损分类方法 分为散在病损组和单一病损组,比较两组的病灶同侧MCA、颈内动脉(ICA)颅内段和颅外段狭窄或闭塞的发生率.结果 散在病损组42例,单一病损组31例.在病损同侧ICA颅外段和MCA闭塞或重度狭窄方面两组差异有统计学意义(28.6%与0,x2=10.6,P=0.001).在病损同侧ICA颅内段并MCA轻中度狭窄方面,两组间差异具有统计学意义(31.0%与9.7%,x2=4.717,P=0.03).散在病损与MCA和(或)ICA严重或多发狭窄呈正相关(OR值为13.7,95%CI:3.6～52.5).在MRA或DSA未发现颅内外大血管狭窄方面,两组间差异具有统计学意义(11.9%与32.3%,x2=4.526,P=0.033).散在病损组与无明显血管狭窄呈负相关(OR值为0.284,95%CI:0.09～0.94).结论 (1)脑梗死急性期DWI显示的MCA区散在性病损患者,MCA和ICA狭窄、甚至闭塞的可能性较大,以ICA颅外段闭塞较为常见;(2)DWI显示单一病损时提示脑供血动脉狭窄程度较轻,范围较局限,小血管病变的可能性相对较高,很少为严重的ICA颅外段狭窄或闭塞.

Abstract：

Objective To investigate the relationship between scattered or single lesion of acute cerebral infarction in middle cerebral artery territory on diffusion-weighted imaging (DWI) and stenosis of middle cerebral artery (MCA) or internal carotid artery (ICA). Methods With exclusion of cardioembolism, 73 consecutive patients with acute cerebral infarction of the unilateral MCA territory on DWI were analyzed. All patients got magnetic resonance imaging (MRI) and angiography (MRA) within 24 hours after onset, and 7 patients also had digital subtraction angiography (DSA). The patients were classified into single lesion group or scattered lesions group according to the DWI findings. The incidence of stenosis or occlusion of ipsolateral MCA, intracranial and extracranial ICA were compared between the two groups. Results 42 patients had scattered lesions and 31 patients had single lesion. The scattered-lesions group had a high incidence of ipsilateral extracranial ICA or MCA occlusion or severe stenosis ( 25.6%versus 0, x2 = 10.6, P = 0.001 ) and a high incidence of ipsilateral intracranial ICA or MCA moderate or mild stenosis (31.0% versus 9.7% ,x2 =4.717, P =0.03 ). A positive correlation was found between the scattered lesions and severe or multifocal stenosis of ipsilateral ICA and MCA ( OR: 13.7, 95% CI: 3.6 to 52.5). There was a low incidence of absence of extra- and intracranial stenosis on MRA or DSA in the scattered-lesions group ( 11.9% versus 32.3%, x2= 4.526, P = 0.033 ). A negative correlation was found between the scattered lesions and absence of large-artery stenosis ( OR: 0.284, 95% CI: 0.09 to 0.94).Conclusions ( 1 ) Patients with acute cerebral infarction and scattered lesions on DWI were more likely to suffer from stenosis or occlusion of ICA or MCA, especially over the extracranial ICA. (2) Patients with single lesion were less likely to have severe or multiple stenosis of MCA and ICA, indicating the relevance of small-vessel pathogenesis.     

Severe ipsilateral carotid stenosis and middle cerebral artery disease in lacunar ischaemic stroke: innocent bystanders?

Objectives Lacunar infarcts are thought to be mostly due to intracranial small vessel disease. Therefore, when a stroke patient with a relevant lacunar infarct does have severe ipsilateral internal carotid artery (ICA) or middle cerebral artery (MCA) disease, it is unclear whether the arterial disease is causative or coincidental. If causative, we would expect ICA/MCA disease to be more severe on the symptomatic side than on the asymptomatic side. Therefore, our aim was to compare the severity of ipsilateral with contralateral ICA and MCA disease in patients with lacunar ischaemic stroke. Methods We studied 259 inpatients and outpatients with a recent lacunar ischaemic stroke and no other prior stroke. We used carotid Duplex ultrasound and transcranial Doppler (TCD) ultrasound to identify ICA and MCA disease, and compared our results with previously published data. Results In our study, there was no difference between the severity of ipsilateral and contralateral ICA stenosis within individuals (median difference 0 %, Wilcoxon paired data p=0.24, comparing severity of ipsilateral and contralateral stenosis). The overall prevalence of severe ipsilateral stenosis was 5 %, and the prevalence of severe contralateral stenosis was 4 % (OR 1.6, 95 % CI 0.6, 4.8). There was no difference in the prevalence of ipsilateral and contralateral MCA disease. A systematic review of the other available studies strengthened this conclusion. Conclusion Carotid stenosis in patients with a lacunar ischaemic stroke may be coincidental. Further studies are required to elucidate the causes of lacunar stroke, and to evaluate the role of carotid endarterectomy. Received: 24 February 2001, Received in revised form: 15 June 2001, Accepted: 3 July 2001     

Diffusion- and perfusion-weighted MRI: influence of severe carotid artery stenosis on the DWI/PWI mismatch in acute stroke

BACKGROUND AND PURPOSE: Diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI) have been used increasingly in recent years to evaluate acute stroke in the emergency setting. In the present study, we compared DWI and PWI findings in acute stroke patients with and without severe extracranial internal carotid artery (ICA) disease. METHODS: Twenty-seven patients with nonlacunar ischemic stroke were selected for this analysis. DWI, PWI, and conventional MRI were performed in all patients within 24 hours of symptom onset and after 1 week. To exclude patients with partial or complete reperfusion, we included only patients with a PWI deficit larger than the DWI lesion. Severe ICA disease (>70% stenosis) was present unilaterally in 9 and bilaterally in 2 patients. Acute DWI lesion volume, the size of the acute PWI/DWI mismatch, and final infarct size (on T2-weighted images) were determined. RESULTS: The PWI/DWI mismatch was significantly larger in patients with severe ICA disease than in patients without extracranial carotid stenosis, both when time-to-peak and mean transit time maps (P<0.01) were used to calculate the mismatch. Quantitative analysis of the time-to-peak delay in the mismatch indicated that a relatively smaller fraction of the total mismatch was critically ischemic in patients with carotid stenosis than in those without. Average lesion volume increased less in the stenosis group (P=0.14), despite the larger PWI/DWI mismatch, and final infarct size was smaller in the stenosis group (P<0.05). In the 2 patients with bilateral ICA disease, variable hemodynamic involvement of the contralateral hemisphere was found in addition to the ipsilateral PWI deficit. CONCLUSIONS: In most acute stroke patients with severe ICA stenosis, a considerably smaller fraction of the total PWI/DWI mismatch is at risk than in patients without carotid disease.     

Low risk of ischemic stroke in patients with reduced internal carotid artery lumen diameter distal to severe symptomatic carotid stenosis: cerebral protection due to low poststenotic flow? On behalf of the European Carotid Surgery Trialists' Collaborative Group

BACKGROUND AND PURPOSE: Patients with recently symptomatic severe carotid stenosis have a high risk of ischemic stroke on medical treatment. The main mechanism of stroke appears to be plaque surface thrombus formation and distal embolism. It is unclear to what extent reduction in blood flow across the stenosis, and the consequent reduction in cerebral perfusion pressure, is also important. Angiographic indices of reduced cerebral perfusion may identify patients at a particularly high risk of stroke who require urgent endarterectomy. The most direct angiographic correlate of poststenotic perfusion pressure is the degree of narrowing of the distal internal carotid artery (ICA) lumen. We sought to develop criteria for the definition of poststenotic narrowing of the ICA and to determine the effect of this and other angiographic characteristics likely to be associated with reduced cerebral perfusion on the risk of ipsilateral ischemic stroke in patients with recently symptomatic carotid stenosis. METHODS: We studied the carotid angiograms of 3007 patients in the European Carotid Surgery Trial. Poststenotic narrowing of the ICA was defined with use of the ratio of the lumen diameter of the ICA to that of the common carotid artery (CCA). The normal range of the ICA/CCA ratio was defined in 2966 symptomatic or contralateral carotid arteries with 0% to 49% stenosis. Arteries with 70% to 99% symptomatic stenosis and an ICA/CCA ratio below this range were categorized as narrowed. We related the presence of narrowing and other angiographic characteristics to the risk of ipsilateral ischemic stroke on medical treatment. RESULTS: An assessment of the ICA/CCA ratio had good interobserver reproducibility. Poststenotic narrowing of the ICA was defined as an ICA/CCA ratio of <0.42. The 5-year risk of ipsilateral carotid territory ischemic stroke on medical treatment was 8% in patients with 70% to 99% stenosis and narrowing of the ICA versus 25% in patients without narrowing (log rank test, P=0.02). This difference remained after correction for other clinical and angiographic variables (hazard ratio 0.40, 95% CI 0.17 to 0.94, P=0. 03). The other angiographic characteristics did not predict stroke. CONCLUSIONS: Poststenotic narrowing of the ICA was associated with a low risk of stroke on medical treatment. This suggests that low flow alone is not usually sufficient to cause ischemic stroke distal to symptomatic carotid stenosis. Poststenotic narrowing may be protective because blood flow distal to the stenosis is insufficient to carry emboli to the brain.     

大脑中动脉区梗死的DWI特点及与其供血动脉狭窄的关系

目的 探讨大脑中动脉(MCA)区脑梗死磁共振扩散加权成像(DWI)成像病灶分布特点及与其供血动脉狭窄程度的关系.方法 回顾性的分析经颅脑磁共振成像(MRI)的DWI序列诊断的急性脑梗死,选择病灶位于MCA分布区,且完善其供血动脉检查,包括头颈部CTA,或颅脑MRA加颈部血管超声的患者108例,排除心源性栓塞、特殊血管病变导致的脑梗死.将梗死按照部位分为腔隙型梗死(SSSI)、皮层下梗死(SI)和混合型梗死(MI),供血动脉分为正常、轻度(50％)、重度(50％)和闭塞.比较不同类型梗死组的供血动脉狭窄的发生率.结果 各种梗死类型的发生率之间差异无统计学意义(x2=1.08,P＞0.05).单纯MCA病变者53例(53/108,49.1％),单纯ICA病变者28例(28/108,25.9％),单纯MCA病变高于单纯ICA病变(x2=12.35,P＜0.01).同侧血管正常者以LI类型的梗死多见,而单纯ICA病变者以MI类型的梗死多见(x2=10.22;10.54,P＜0.01);三种梗死类型在单纯MCA病变患者中差异无统计学意义(x2=0.25,P＞0.05);在单纯MCA病变者中,SI梗死类型多见于MCA闭塞患者(x2=7.45,P＜0.05).LI梗死类型多见于MCA轻度或重度狭窄患者(x2=6.39,P＜0.05).结论 结合DWI和相应血管检查对于明确MCA区动脉粥样硬化性脑梗死的病因和机制有一定帮助.基底节区的腔隙梗死,相应血管检查正常提示小血管病的可能大;MCA存在一定狭窄则可能是穿支受累造成;ICA病变多累及皮层,包括皮层型分水岭区梗死;而不同程度的MCA病变其梗死形态没有本质区别,皮层下梗死更多见MCA闭塞患者.     

Patterns of cerebral perfusion in patients with asymptomatic internal carotid artery disease

BACKGROUND: The perfusion profile of patients with asymptomatic internal carotid artery (ICA) disease has not been well studied. The purpose of this study is to describe the perfusion patterns of patients with asymptomatic ICA disease using computed tomography perfusion (CTP) and its potential value in identifying patients at higher risk for transient ischemic attacks (TIAs) or strokes. METHODS: We analyzed 32 patients with asymptomatic high grade ICA disease who had CTP and computed tomography angiography (CTA) of the head and neck. Twenty-four patients had severe ICA stenosis and eight had ICA occlusion. The degree of ipsilateral external carotid artery (ECA) and contralateral ICA stenosis, patency of the anterior communicating artery (ACOM), A1 segment and posterior communicating artery (PCOM) were evaluated in all patients. RESULTS: Sixteen patients had normal CTP and the other 16 patients had cerebral hypoperfusion, characterized by abnormalities in one or more of the three perfusion maps. Ipsilateral hypoplastic A1 segment was more frequent in the group with cerebral hypoperfusion (p = 0.025). Ipsilateral TIAs occurred in two patients, both with cerebral hypoperfusion. CONCLUSION: Cerebral hypoperfusion is present in half of the patients with asymptomatic ICA disease, predominantly in patients with a hypoplastic ipsilateral A1 segment. These patients likely represent a higher-risk group for symptomatic brain ischemia.     

Ultrasonographic markers of vascular risk in patients with asymptomatic carotid stenosis

Six-hundred twenty-one subjects with unilateral asymptomatic severe internal carotid artery (ICA) stenosis were prospectively evaluated with a median follow-up of 27 months (min=6, max=68). Vascular risk profile, plaque characteristic, stenosis progression, and common carotid artery intima-media thickness (IMT) were investigated in all patients. Outcome measures were occurrence of ischemic stroke ipsilateral to ICA stenosis and vascular death, while myocardial infarction, contralateral strokes, and transient ischemic attack were considered as competing events. A total of 99 subjects (15.9%) suffered from a vascular event. Among them, 39 were strokes ipsilateral to the stenosis (6.3%). Degree of stenosis, stenosis progression, and common carotid artery IMT resulted as independent predictive factors of ipsilateral stroke. Considering a stenosis of 60% to 70% as reference, a degree between 71% and 90% increased the risk by 2.45, while a degree between 91% and 99% increased the risk by 3.26. The progression of stenosis was a strong risk factor (hazard ratio=4.32). Finally, the role of carotid IMT was confirmed as crucial additional measure, with an increased risk by 25% for each 0.1 mm IMT increase. Our data suggest that IMT, stenosis progression and severity should be considered as risk factors for cerebrovascular events in asymptomatic subjects with severe ICA stenosis.     

Vision in multiple sclerosis: the story, structure-function correlations, and models for neuroprotection

Visual dysfunction is one of the most common clinical manifestations of multiple sclerosis (MS). Just over a decade ago, MS clinical trials did not include visual outcomes, but experts recognized the need for more sensitive measures of visual function. Low-contrast letter acuity emerged as the leading candidate to measure visual disability in MS, and subsequent studies found low-contrast acuity testing to correlate well with brain MRI lesion burden, visual-evoked potentials, quality of life (QOL), and retinal nerve fiber layer (RNFL) loss, as measured by optical coherence tomography (OCT). OCT in MS has allowed for assessment of structure-function correlations that make the anterior visual pathway and acute optic neuritis (ON) ideal models for testing novel agents for neuroprotection and repair. New therapies that reduce axonal loss by neuroprotective or myelin repair mechanisms can now be assessed noninvasively by OCT and coupled with visual function data. Based on OCT studies in MS, RNFL thickness is reduced significantly among patients (92 μm) vs controls (105 μm) and is particularly reduced in MS eyes with a history of ON (85 μm). Worsening of visual function by a clinically significant ≥ 7 letters or approximately 1.5 lines for low-contrast acuity is associated with approximately 4.5 μm reductions in RNFL thickness in MS eyes. Longitudinal studies of OCT have also shown RNFL axonal loss over time that occurs even in the absence of acute ON and that correlates with clinically meaningful worsening of vision and QOL, even in patients with benign MS. The latest OCT investigations involve high-resolution spectral-domain (SD) OCT with segmentation and measurement of specific retinal layers using computerized algorithms. These methods allow quantitation of ganglion cell (neuronal) layer loss and axonal degeneration in MS in vivo. In this review, we examine the data from these studies and ongoing trials that highlight the entity of ON as a model to investigate neuroprotection and neurorepair. In doing so, we also present representative group data from studies that have examined visual function, OCT measures, and QOL scales in patients with MS and ON and disease-free controls. These data, and those from recent meta-analyses, may be used to provide reference values for the development of clinical trial protocols.     

Antithrombotic treatment of ischemic stroke among patients with occlusion or severe stenosis of the internal carotid artery: A report of the Trial of Org 10172 in Acute Stroke Treatment (TOAST).

OBJECTIVE: To examine the responses to early IV administration of an anticoagulant or placebo started within 24 hours of stroke among persons with an ipsilateral occlusion or severe stenosis of the internal carotid artery (ICA) identified by carotid duplex imaging. BACKGROUND: Patients with ischemic stroke of the cerebral hemisphere secondary to an ipsilateral occlusion or severe stenosis of the ICA generally have a poor prognosis. Early, accurate identification of these patients might permit improved treatment. METHODS: Exploratory analysis of outcomes at 7 days and 3 months was performed among patients enrolled in the Trial of Org 10172 in Acute Stroke Treatment (TOAST) who had an ischemic stroke in the cerebral hemisphere ipsilateral to an occlusion or a stenosis >50% of the ICA identified by carotid duplex imaging. RESULTS: Regardless of treatment, patients with duplex evidence of an occlusion of the ICA had more severe strokes and poorer outcomes at 7 days and 3 months than patients who had a stenosis. Favorable outcomes at 7 days were noted in 64 of 119 patients given danaparoid (53.8%) and 41 of 108 patients treated with placebo (38.0%; p = 0.023). By 3 months, favorable outcomes were noted in 82 patients given danaparoid (68.3%) and 58 patients administered placebo (53.2%; p = 0.021). CONCLUSIONS: Early identification by duplex imaging of an occlusion or severe stenosis of the ICA ipsilateral to a hemispheric ischemic stroke might improve selection of patients who could be treated with emergent anticoagulation. Further testing of this approach is needed.