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。     

CT血管造影联合CT灌注在缺血性脑卒中的临床应用

目的探讨血管造影联合CT灌注在缺血性脑卒中的临床价值。方法选择2012-03—2014-03在我院诊治的缺血性脑卒中患者42例,采用东芝320排CT行头部CTA及CTP检查。观察两种检查方法对缺血性脑卒中的诊断情况,探讨颅内及颈部血管的狭窄与脑组织灌注异常区的关系。结果 CTP检查发现与临床症状相符的异常灌注区36例,感兴趣区的脑血容量及脑血流量较镜像区显著降低(P0.05);感兴趣区的平均通过时间显著延长(P0.05)。CTA检查发现颈部及颅内血管狭窄32例,10例未发现有血管狭窄。CTA有责任血管狭窄患者CTP阳性率(71.43%)显著高于CTA无责任血管狭窄者(14.29%)。结论缺血性脑卒中行CT血管造影联合CT灌注能准确反映脑组织血流动力学变化,有效判定颈部及颅内责任血管是否存在狭窄,为临床诊断提供依据。     

64层螺旋CT灌注成像和血管成像在急性缺血性脑卒中的应用

目的：探讨64层螺旋CT 灌注成像（CTP）、CT血管成像（CTA）在急性缺血性脑卒中的应用价值。方法对30例急性缺血性脑卒中患者,于发病12 h内行头CT平扫、CTP、CTA检查,分析平扫及灌注CT表现,计算灌注缺损区CBF、CBV、MTT各参数值,与对侧相应区灌注参数进行比较,重建颈段和脑内动脉CTA图像,并于发病2～7 d复查CT平扫。结果30例急性缺血性脑卒中患者,15例C T平扫未发现异常,14例可见腔隙梗死灶或软化灶,1例可见脑梗死早期低密度改变。10例C T P未见明显异常,20例C T P发现与临床症状相对应的大小不等的灌注减低区,18例可见不同范围缺血半暗带。CTA 显示12例未见明显异常,18例可见血管狭窄或闭塞。结论 CTP、CTA能够快速准确反映缺血部位及范围,显示缺血半暗带,判断闭塞血管,对早期诊断急性脑梗死和指导溶栓治疗具有重要价值。     

缺血性脑卒中早期CT灌注成像的临床应用价值

目的 探讨缺血性脑卒中早期CT灌注成像（CTPI）的临床应用价值。方法 对45例发病24h内的缺血性脑卒中患者行头颅CT平扫与CTPI检查,计算缺血半暗带区及梗死区相对脑血流量（rCBF）、相对脑血容量（rCBV）、相对平均通过时间（rMTT）、相对峰值时间（rTTP）、相对峰值增强（rPE）的灌注参数及各个参数图异常灌注区面积。结果 CT平扫显示脑缺血性改变29例,其中为责任病灶21例,未见异常16例,未见责任病灶24例;对缺血性脑卒中早期诊断的敏感性为46．67％（21／45）,特异性为72．41％（21／29）。CTPI显示灌注异常44例,均为责任病灶;灌注正常1例,后经头颅MRI证实为急性脑干梗死;对缺血性脑卒中早期诊断的敏感性为97．78％（44／45）,特异性为100％（44／44）。CTPI较CT平扫对急性脑缺血性病灶更敏感（P〈0．01）。缺血半暗带区及梗死区各个灌注参数相对值之间呈正相关（均P〈0．01）。CTPI各个参数图异常灌注区面积之间呈正相关（均P〈0．01）。结论 CTPI能够早期诊断缺血性脑卒中;定量分析可区分中心梗死区、缺血半暗带区,有助于早期选择治疗方案。     

CT脑灌注与血管造影在急性缺血性脑卒中的临床应用与分析

目的探讨CT脑灌注(CTPI)与血管造影在急性缺血性脑卒中中的临床应用价值。方法选择29例急性缺血性脑卒中患者为研究对象,采用东芝Aquilion 64排CT行头颈部CTA及CTPI检查,观察两者对急性缺血性脑卒中诊断情况,分析CTPI与CTA对急性缺血性脑卒中诊断的一致性。结果①29例患者CT灌注图上发现与临床症状相对应的灌注异常区共25例,阳性率为86.2%(25/29),高于普通CT扫描的27.6%(8/29),差异具有统计学意义(P0.05)。②灌注异常区的CBF、CBV、MTT三组参数值与镜像健侧相比差异有显著统计学意义(P0.05);③CTA血管检查结果发现单纯颈内动脉狭窄5处;单纯颅内动脉狭窄10处;颈内动脉及颅内动脉均狭窄4例。④病例组CTPI联合CTA检查结果比较,病例组存在责任血管的患者CTPI检查阳性率为65.51%(19/29)高于无责任血管者的20.69%(6/29),差异具有统计学意义(P0.05)。结论 CTPI与CTA可以清晰的显示缺血性脑卒中脑内病灶及责任动脉,能够提高更多有价值的信息。     

多层螺旋CT脑灌注成像与平扫CT值差值的测量对诊断急性脑梗死的价值

目的探讨多层螺旋CT(MSCT)脑灌注成像与测量CT值的差值(△Hu)在急性脑梗死早期诊断中的价值。方法对34例临床拟诊为急性脑梗死的患者行头部CT平扫和脑CT灌注成像。评价脑CT灌注成像的达峰时间(TTP),脑血流量(CBF),脑血容量(CBV),测量两侧对称部位CT值的差值(△Hu)。全部病例3⁷ d内复查头部CT及临床随访。另选取34例无脑部疾病、神经系统功能正常的为对照组。结果 34例病例中,头部CT平扫肉眼观察发现可疑病灶15例,测量对称部位CT值差值发现可疑病灶21例;脑CTP显示:32例脑CTP灌注异常,2例脑CTP灌注正常,脑CTP显示患者感兴趣区内脑血流量(rCBF)、脑血容量(rCBV)、对比剂达峰时间(rTTP)明显改变,病灶侧与对照侧、病灶中心区与周边区比较,差异有显著意义(P<0.01)。头部CT平扫肉眼观察发现病灶的敏感度44.11%,脑CTP发现病灶的敏感度94.11%。结论脑CTP检查能够早期诊断急性脑梗死,定量分析可区分中心梗死区与缺血半暗带区,有助于临床医生判断梗死病灶的存在和早期选择治疗方案。     

脑灌注成像在急性脑血管病诊断中的应用

目的探讨脑灌注成像在急性脑血管病诊断中的应用。方法 2010-01～2011-01急性缺血性脑梗死患者189例,急性期进行常规CT平扫及CT灌注成像检查,并进行随访,于发病1周后进行CT平扫。结果 189例急性缺血性脑血管患者急性期常规CT扫描检出80例有脑梗死病灶,检出率42.33%;脑CT灌注成像检出180例有脑梗死病灶,检出率95.24%。结论脑CT灌注成像检查可及早、准确检测脑内缺血性病变的位置、范围及程度等脑血流动力学变化,为治疗起到良好的指导作用。     

急诊MRI快速评价对静脉溶栓治疗超急性期缺血性脑卒中的指导作用

目的探讨急诊MRI快速评价对静脉溶栓治疗超急性期缺血性脑卒中的指导价值。方法对224例发病不足12h的急性脑梗死患者予以CT平扫或MR颅脑快速成像序列扫描,其中91例超急性期缺血性脑卒中患者予以静脉溶栓治疗。对比治疗前后美国国立卫生院神经功能缺损评分(NIHSS)、Barthel指数(BI评分)、改良Rankin评分(mRS评分)变化,随访3个月,记录其并发症发生率及病死率。结果末次随访时,91例患者NIHSS评分及mRS评分均较治疗前显著降低,且BI评分较治疗前显著增高,差异有统计学意义(P0.05);在为期3个月的随访中,91例患者中仅1例(1.1%)因症状性颅内出血并发脑疝死亡,非症状性颅内出血9例(9.9%),症状性颅内出血3例(3.3%)。结论对经急诊MRI快速评价指导超急性期缺血性脑卒中患者予以静脉溶栓治疗的效果确切,可有效促进其神经功能恢复,对全面提升预后质量、改善其生活自理能力等具有积极影响,值得临床推广。     

多时相CTA联合脑CTP对缺血性脑卒中患者诊断的价值研究

目的 分析多时相计算机断层扫描血管造影(CTA)联合计算机断层扫描灌注成像(CTP)对缺血性脑卒中患者诊断的临床价值.方法 收集来东南大学附属中大医院江北院区就诊的临床高度怀疑的患者160例,采用多时相CTA和CTP对患者进行检查,分析CTP与多时相CTA对缺血性脑卒中检查的影像学特征及临床诊断价值,然后对梗死区与半暗...     

CT灌注成像联合CT血管造影在颈内动脉系统短暂性脑缺血发作中的应用研究

目的探讨CT灌注成像联合CT血管造影在颈内动脉系统短暂性脑缺血发作中的应用价值。方法颈内动脉系统短暂性脑缺血发作患者63例,于症状发作后7d内采用东芝320排螺旋CT行头部CT灌注成像以及CT血管造影,观察并比较感兴趣区以及镜像区CT灌注成像各参数,以及两种影像学检查的符合情况。结果比较感兴趣区与镜像区CT灌注成像各参数发现,感兴趣区与镜像区脑血容量无显著性差异(P0.05);感兴趣的脑血流量显著低于镜像区(P0.05);感兴趣区的造影剂通过时间显著短于镜像区(P0.05)。CT血管造影发现责任血管狭窄54例,其中灌注异常患者43例,CT血管造影未发现责任血管狭窄9例,灌注异常3例,CT灌注异常在有责任血管狭窄的阳性率显著高于无责任血管狭窄(P0.05)。结论 CT灌注成像可反映颈内动脉系统短暂性脑缺血发作的脑灌注状态,CT血管造影可用于检测责任血管的病变情况,CT灌注成像联合CT血管造影可为颈内动脉系统短暂性脑缺血发作的病因以及为诊断提供影像学依据。     

Magnetic resonance perfusion imaging in acute ischemic stroke using continuous arterial spin labeling

BACKGROUND AND PURPOSE: Continuous arterial spin-labeled perfusion MRI (CASL-PI) uses electromagnetically labeled arterial blood water as a diffusible tracer to noninvasively measure cerebral blood flow (CBF). We hypothesized that CASL-PI could detect perfusion deficits and perfusion/diffusion mismatches and predict outcome in acute ischemic stroke. METHODS: We studied 15 patients with acute ischemic stroke within 24 hours of symptom onset. With the use of a 6-minute imaging protocol, CASL-PI was measured at 1.5 T in 8-mm contiguous supratentorial slices with a 3.75-mm in-plane resolution. Diffusion-weighted images were also obtained. Visual inspection for perfusion deficits, perfusion/diffusion mismatches, and effects of delayed arterial transit was performed. CBF in predetermined vascular territories was quantified by transformation into Talairach space. Regional CBF values were correlated with National Institutes of Health Stroke Scale (NIHSS) score on admission and Rankin Scale (RS) score at 30 days. RESULTS: Interpretable CASL-PI images were obtained in all patients. Perfusion deficits were consistent with symptoms and/or diffusion-weighted imaging abnormalities. Eleven patients had hypoperfusion, 3 had normal perfusion, and 1 had relative hyperperfusion. Perfusion/diffusion mismatches were present in 8 patients. Delayed arterial transit effect was present in 7 patients; serial imaging in 2 of them showed that the delayed arterial transit area did not succumb to infarction. CBF in the affected hemisphere correlated with NIHSS and RS scores (P=0.037 and P=0.003, Spearman rank correlation). The interhemispheric percent difference in middle cerebral artery CBF correlated with NIHSS and RS scores (P=0.007 and P=0.0002, respectively). CONCLUSIONS: CASL-PI provides rapid noninvasive multislice imaging in acute ischemic stroke. It depicts perfusion deficits and perfusion/diffusion mismatches and quantifies regional CBF. CASL-PI CBF asymmetries correlate with severity and outcome. Delayed arterial transit effects may indicate collateral flow.     

Clinical application of brain perfusion imaging in detecting stroke mimics: A review

Stroke mimics constitute a significant proportion of patients with suspected acute ischemic stroke. These conditions may resemble acute ischemic stroke and demonstrate abnormalities on perfusion imaging sequences. The most common stroke mimics include seizure/epilepsy, migraine with aura, brain tumors, functional disorders, infectious encephalopathies, Wernicke's encephalopathy, and metabolic abnormalities. Brain perfusion imaging techniques, particularly computed tomography perfusion and magnetic resonance perfusion, are being widely used in routine clinical practice for treatment selection in patients presenting with large vessel occlusion. At the same time, the utilization of these imaging modalities enables the opportunity to better diagnose patients with stroke mimics in a time-sensitive setting, leading to appropriate management, decision-making, and resource allocation. In this review, we describe patterns of perfusion abnormalities that could discriminate patients with stroke mimics from those with acute ischemic stroke and provide specific case examples to illustrate these perfusion abnormalities. In addition, we discuss the challenges associated with interpretation of perfusion images in stroke-related pathologies. In general, perfusion imaging can provide additional information in some cases—when used in combination with conventional magnetic resonance imaging and computed tomography—and might help in detecting stroke mimics among patients who present with acute onset focal neurological symptoms.     

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。     

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.     

Emergency imaging of cerebrovascular accidents

Over the last 25 years, advances in neuroimaging have significantly changed the evaluation and management of acute stroke syndromes. In the seventies, computed tomography (CT) could differentiate between ischemic and hemorrhagic stroke. Magnetic resonance imaging (MRI) is nowadays the imaging modality of choice in the initial assessment of acute stroke. MRI images can better discriminate acute, subacute and chronic infarcts, differentiate venous from arterial infarcts, detect arterial dissection, stenosis or occlusion. Diffusion-weighted images are highly sensitive and specific to acute infarction and the combination with perfusion technique is suitable to define potentially reversible ischemia (area of cerebral "mismatch" which is thought to represent the so-called ischemic penumbra). This penumbra is a potential therapeutic target of valuable interest for the treating physician.     

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。     

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.