醒后卒中的研究进展

醒后卒中（WUS）是指入睡时无神经系统症状，觉醒后患者本人或目击者发现有卒中症状， 占急性缺血性脑卒中的 14.3%～29.6%。由于发病时间的不确定，通常不适用于急性缺血性卒中时间窗 内特殊治疗。近年来，随着多模式CT及磁共振成像对缺血性卒中梗死灶及缺血半暗带识别的技术发展， 越来越多的证据表明静脉溶栓、机械取栓等治疗方案使 WUS 患者更好地获益。现对 WUS 的病理生理 机制、危险因素、临床及影像学特征、治疗方案的最新进展作一综述     

多模式CT对卒中患者血脑屏障完整性和侧支循环的评估价值

多模式计算机断层扫描（computed tomography,CT）对急性缺血性卒中患者的重要性逐 渐引起临床医生的重视,在脑缺血超急性期,CT平扫可对脑出血或其他脑部疾病进行鉴别,CT血管 造影可评估血管梗死部位和侧支循环状态,CT灌注成像可以通过毛细血管的实际灌注情况来评估 脑组织的活力,并通过计算血脑屏障的表面通透性（permeability surface,PS）判断血脑屏障的完整 性,进一步指导临床医生溶栓及血管性治疗方案的制定,也可以预测卒中后患者发生出血转化的风 险。临床诊疗过程中,结合多模式CT提供的信息,可对急性缺血性卒中患者出现出血转化和临床预后 进行全面评估。     

急性缺血性卒中静脉溶栓前后多模式影像评估分析

目的应用多模式影像学检查对急性缺血性脑卒中静脉溶栓进行评估。方法回顾性分析行急性缺血性卒中静脉溶栓的患者69例,通过对比缺血性脑卒中患者静脉溶栓前后多模式影像检查方法的选择及临床疗效进行研究。结果静脉溶栓前仅检查CT的占68.1%;静脉溶栓前开启多模式影像的占31.9%。静脉溶栓后立刻或同时开启多模式影像的占30.4%。结论结合医院放射科设备配置及卒中中心发展状况,溶栓二线合理选择适合自身特点的多模式影像并判断何时开启多模式影像;结合灌注成像的分析确定梗死核心和缺血半暗带,为超时间窗的rt-PA静脉溶栓和血管内治疗进行指导评估,使更多的缺血性卒中患者从中受益。     

颈动脉粥样硬化斑块的磁共振成像特点

影像学检查在缺血性卒中的诊治、预后评估中的价值毋庸置疑。随着以“病人为中心”、在循证医学基础之上的个体化医疗观念的不断深入,临床对影像学检查的要求也越来越高。在急性缺血性卒中的影像学检查中,准确、快捷是首要的;而对非急性缺血性卒中而言,准确和全面则是下一步治疗和预防的基础。本期的几篇研究论文对此进行了初步的尝试。     

多模式CT在评估急性缺血性卒中脑侧支循环中的应用

多模式计算机断层扫描（computed tomography,CT）包括CT平扫（non-contrast CT,NCCT）、 CT灌注成像（CT perfusion,CTP）、CT血管成像（CT angiography,CTA）,可以对急性缺血性卒中后侧支 循环进行全面评估,评估脑灌注状态,了解脑侧支循环建立或开放情况,判断临床预后,在急性缺血 性卒中的诊疗过程中发挥重要的作用。本文就多模式CT在缺血性卒中中的应用进行综述,以期使患 者获益更多。     

成人缺血性Moyamoya病临床分析

目的 回顾性分析成人缺血性Moyamoya病的临床表现及各种影像学的特点.方法 回顾性分析11例缺血性Moyamoya病患者的临床资料.结果 11例病例中男8例,女3例,年龄30～65岁,平均(48.5±12.59)岁,临床表现多样,影像学表现各异.结论 成人缺血性Moyamoya病临床及影像学表现各异,并与动脉硬化致脑动脉闭塞的治疗策略不同,影像学检查中DSA是有效、安全、必要的检查方法,为下一步治疗提供准确依据.     

影像学指导扩大时间窗急性缺血性卒中溶栓治疗的进展

1996年美国食品及药物管理局（food and drug administration,FDA）规定缺血性卒中静脉应用重组组织型纤溶酶原激活剂（recombinant tissue type plasminogen activator,rt-PA）的时间窗为3 h,但越来越多的证据表明,先进的影像学指导扩大时间窗静脉溶栓治疗具有安全性和有效性。本文将对影像学指导扩大时间窗急性缺血性卒中溶栓治疗的进展进行综述。     

多层螺旋CT灌注成像在缺血性脑卒中的临床应用

多层螺旋CT灌注成像(CT perfusion,CTP)因其成本较低、精确性高、操作容易等优点,在判断脑血流、脑代谢方面为临床提供了新的途径,已逐渐成为缺血性脑卒中的重要诊断方法,对目前指导治疗和观察疗效具有非常重要的意义.现就CTP检查方法和各项指标意义进行阐述,探讨CTP在缺血性脑卒中的临床应用,同时与其他灌注成像方法作比较,提出脑卒中"一站式"CT检查方案.     

CT灌注成像应用于早期缺血性脑血管病的相关研究

目的探讨CT灌注成像（CTPI）对早期缺血性脑血管病的应用价值。方法45例早期急性缺血性脑血管患者中（发病时间≤24h）,行头部常规CT平扫后,立即行CTPI及TCD检查,24-72h后复查颅脑CT。对所得灌注扫描源数据用Adw 4.2软件行后处理得CT灌注参数图并进行诊断,最后对灌注及CT、TCD结果进行分析并行统计学处理。结果CT平扫：敏感度44.44%,特异度68.97%。CTPI：敏感度91.11%,特异度95.35%。TCD：敏感度71.11%。四格表χ2检验证明CTPI较CT平扫、TCD检出早期脑内缺血病灶均敏感（χ2=9.257,χ2=5.874,P〈0.01）;而单纯TCD检查与CT平扫对检出早期脑内缺血病灶无明显差异（χ2=0.458,P〉0.05）。结论脑CT灌注成像的敏感度、特异度及诊断率均明显高于CT及TCD,能很好地评价脑血流动力学改变,准确显示缺血脑组织的部位和范围,可早期诊断急性缺血性脑梗死,并评价其血流灌注情况,为临床早期诊断、预防及治疗脑梗死提供影像学依据,同时对于早期选择治疗方案、指导临床有重要意义。     

64排螺旋CT灌注成像在急性缺血性脑卒中的应用价值

目的探讨64排CT灌注成像在缺血性脑卒中急性期的临床应用价值。方法对44例发病6h内的缺血性脑卒中患者行头部CT平扫及CT灌注成像检查,计算各灌注参数值。结果 44例患者中38例头部CT灌注成像发现与临床症状相应的低灌注区,进行了溶栓治疗;6例患者头部CT灌注成像未发现与临床症状相应的低灌注区,后MR I证实为急性基底节区脑梗死。结论 CT灌注成像能够快速、准确反映缺血部位及范围,对缺血性脑卒中急性期的诊断和治疗有重要价值。     

A Pictorial Essay of Brain Perfusion‐CT: Not Every Abnormality Is a Stroke!

Perfusion‐CT (PCT) of the brain is a rapidly evolving imaging technique used to assess blood supply to the brain parenchyma. PCT is readily available at most imaging centers, resulting in steadily increasing use of this imaging technique. Though PCT was initially introduced and still most widely used to evaluate patients with acute ischemic stroke, a wide variety of other pathologic processes demonstrate abnormal perfusion maps. Therefore, it is important for the radiologist to recognize altered perfusion patterns observed in diseases other than typical ischemic stroke. The goal of this article is to show the perfusion maps and review the perfusion patterns observed in some subtypes of atypical stroke and in neurological entities other than stroke, so that they are recognized and not confused with the PCT patterns observed in patients with typical ischemic stroke.     

Role of neuroimaging before reperfusion therapy. Part 1 – IV thrombolysis – Review

This review paper summarises the yield of the different imaging modalities in the evaluation of patients for IV thrombolysis. Non-contrast CT and CTA or brain MRI combined with MRA are the recommended sequences for the evaluation of patients within the 4.5 hours time window. Multimodal MRI (DWI/PWI), and more recently, CT perfusion, offer reliable surrogate of salvageable penumbra, the target mismatch, which is now currently used as selection criteria for revascularisation treatment in an extended time window. Those sequences may also help the physician for the management of other limited cases when the diagnosis of acute ischemic stroke is difficult. Another approach the DWI/FLAIR mismatch has been proposed to identify among wake-up stroke patients those who have been experiencing an acute ischemic stroke evolving from less than 4.5 hrs. Other biomarkers, such as the clot imaging on MRI and CT, help to predict the recanalisation rate after IVT, while the impact of the presence microbleeds on MRI remains to be determined.     

The establishment of a telestroke service using multimodal CT imaging decision assistance: “Turning on the fog lights”

Telestroke services have been shown to increase stroke therapy access in rural areas. The implementation of advanced CT imaging for patient assessment may improve patient selection and detection of stroke mimics in conjunction with telestroke.We implemented a telestroke service supported by multimodal CT imaging in a rural hospital in Australia. Over 21 months we conducted an evaluation of service activation, thrombolysis rates and use of multimodal imaging to assess the feasibility of the service. Rates of symptomatic intracranial haemorrhage and 90-day modified Rankin Score were used as safety outcomes. Fifty-eight patients were assessed using telestroke, of which 41 were regarded to be acute ischemic strokes and 17 to be stroke mimics on clinical grounds. Of the 41 acute stroke patients, 22 patients were deemed eligible for thrombolysis. Using multimodal CT imaging, 8 more patients were excluded from treatment because of lack of treatment target. Multimodal imaging failed to be obtained in one patient. For the 14 treated patients, median door-imaging time was 38 min. Median door-treatment time was 91 min. A 90-day mRS ⩽2 was achieved in 40% of treated patients. We conclude that a telestroke service using advanced CT imaging for therapy decision assistance can be successfully implemented in regional Australia and can be used to guide acute stroke treatment decision-making and improve access to thrombolytic therapy. Efficiency and safety is comparable to established telestroke services.     

VCTDSA联合CT灌注成像对急性缺血性脑卒中影像诊断价值

目的探讨容积CT数字减影血管造影VCTDSA联合CT灌注成像在急性缺血性脑卒中的诊断价值。方法对30例临床诊断为急性缺血性脑卒中的患者于发病后24h内行VCTDSA联合CT灌注成像,观察CT平扫表现及灌注图像、VCTDSA重建图像结果。测定相应区域脑血流量(CBF),脑血容量(CBV),平均通过时间(MTT)和达峰时间(TTP)。结果 25例急性缺血性脑卒中患者头部CT平扫未发现与临床症状相对应的脑缺血区,CT灌注图上可发现与临床症状相对应的脑缺血区。CT灌注成像表现为CBF下降、CBV下降、MTT延长、TTP延长或无TTP出现。VCTDSA可见23例患者相应责任血管的不同程度的狭窄,其余7例患者未检出相应责任血管狭窄。结论 CT灌注成像在急性缺血性脑卒中的早期诊断中有很重要的价值。VCTDSA能发现缺血病变的原因,为临床进一步治疗提供确切依据。     

缺血性脑血管病搭桥手术前后CT灌注的应用简

目的探讨缺肌『生脑血管病血管搭桥治疗中CT灌注的应用价值。方法对2组实施搭桥手术的缺血性脑血管病患者在手术前后进行CT灌注检查,再对手术前后的结果进行统计学分析。结果手术前2组患者绝大多数都存在着手术侧脑血流量（CBF）和脑血容量（CBV）降低,达峰时间（TTP）延长情况,符合搭桥手术指征。手术后2组患者相对脑血流量（rCBF）均显著升高,显示了搭桥手术对这2组患者缺血区局脑血流灌注的改善效果显著;其中烟雾病组相对脑血容量（rCBV）较手术前升高,而非烟雾病搭桥组rCBV与术前变化不明显;烟雾病组相对达峰时间（TTP）较手术前缩短,非烟雾病组册P改变不明显。结论CT灌注对局部脑血流的评价结果是缺血性脑血管病外科治疗前的重要手术指证;CT灌注对于缺血性脑血管病外科治疗后的疗效评估很有价值。     

Imaging of brain ischemia

The extent of the penumbra and the core of an acute ischemic stroke influence, at the given time, the impact of the recanalization of the occluded vessel on the outcome. Research studies have demonstrated that quantitative MR diffusion imaging and, to a lesser extent, CT perfusion (CTP) could provide an acceptable estimation of the size of the core, while perfusion imaging thresholds could outline critically hypoperfused regions. Several software programs now automatically process reliable quantitative diffusion-weighted imaging (DWI) and perfusion maps in real time, making them available for clinical routine. Studies investigating whether acute MRI profile could select patient for acute recanalization after the 4.5 h time window approved for rtPA administration are ongoing. Transient ischemic attack (TIA) is a major risk factor for stroke but its clinical diagnosis is difficult. MRI can confirm the ischemic nature of transient neurological symptoms among 50% of the patients and the presence of an acute diffusion lesion is an independent risk factor for acute stroke. Multimodal imaging of ischemic stroke and TIA provides a tissue-based characterization of the ischemic lesion that is dramatically influencing the diagnosis and the management of the patients.     

Blood microRNAs as potential diagnostic markers for hemorrhagic stroke

Proper medical treatment of a stroke victim relies on accurate and rapid differentiation between ischemic and hemorrhagic stroke, which in current practice is performed by computerized tomography (CT) or magnetic resonance imaging (MRI) scans. A panel of microRNAs could be an extremely useful clinical tool for distinguishing between hemorrhagic and ischemic stroke. hTis review has shown that blood miRNA proifle can distinguish hemorrhagic from ischemic stroke in patients and in experimental animal models. It also seems likely they can differentiate between intracerebral and subarachnoid hemorrhage stroke. hTe miRNA proifle in cerebrospinal lfuid could be a useful diagnostic tool for subarachnoid hemorrhagic stroke. Decreased or increased miRNA levels may be needed either as prevention or treatment of stroke. Administration in vivo of miR-130a inhibitor or miRNA mimic (miR-367, miR-223) in an intracerebral hemorrhage animal model improved neurological outcomes.