CT脑灌注成像与CT血管成像对颈动脉狭窄性短暂性脑缺血发作的诊断价值

目的探讨CT脑灌注成像与CT血管成像对颈动脉狭窄所致短暂性脑缺血发作的诊断价值。方法对我院2012-01—2014-01收治的36例临床诊断为短暂性脑缺血发作患者的影像学资料进行回顾性分析,所有患者均行颅CT平扫、CT脑灌注成像和CT血管成像检查,测定兴趣区及对侧相应区域局部脑血流量(rCBF)、局部脑血容量(rCBV)、平均通过时间(MTT)和达峰时间(TTP),评价颈动脉的狭窄程度与斑块的性质。结果 36例患者行CT平扫均未发现与临床症状相对应的病灶,CT血管造影显示责任血管狭窄28例,发现颈动脉斑块54块,而CT灌注成像显示异常24例,阳性率85.71%,其中病灶侧TTP、rCBF、MTT值与对照侧比较差异均有统计学意义(P0.05),而rCBV与对照侧对比差异无统计学意义(P0.05);CT血管造影显示责任血管无狭窄8例,而CT灌注成像异常3例,阳性率37.5%,二者比较差异有统计学意义(P0.05)。Ⅰ期患者MTT低于Ⅱ期,rCBF高于Ⅱ期,差异均有统计学意义(P0.05);Ⅰ期、Ⅱ期rCBV相似,差异无统计学意义(P0.05)。经半年随访,其中5例发展成为脑梗死。结论 CT脑灌注成像结合CTA可同时观察短暂性脑缺血发作患者脑组织的血流动力学变化与颈内动脉的血管形态变化,对短暂性脑缺血发作的诊断具有重要价值,值得临床推广应用。     

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。     

CT灌注成像联合数字减影血管造影在颈内动脉系统脑梗死中的诊断价值

目的探讨CT灌注成像(CTPI)联合数字减影血管造影在颈内动脉系统脑梗死中的诊断价值。方法选择颈内动脉系统脑梗死患者30例为研究对象,均接受CTPI及数字减影血管造影检查。观察CTPI对脑梗死诊断情况,比较不同感兴趣区相关参数的差异。分析数字减影血管造影显示脑动脉狭窄与CTPI检查相关性。结果 (1)CTPI对颈内动脉系统脑梗死诊断准确率为100.0%。与镜像区比较,病变部位CTPI参数CBV、CBF显著降低,MTT显著延长,差异有统计学意义(P0.05);(2)数字减影血管造影显示26例存在血管狭窄,其中单发狭窄20例,包括颈总动脉3例,颈内动脉5例,大脑前动脉4例,大脑中动脉8例;多发狭窄6例;(3)CTPI阳性与数字减影血管造影责任血管一致者比例为86.7%。结论 CTPI可清晰显示颈内动脉系统脑梗死脑内病灶,数字减影血管造影可以清晰显示责任血管,两者具有较好的一致性。     

探讨CT脑灌注与血管造影在急性脑梗死中的应用

目的探讨CT脑灌注与血管造影在急性脑梗死中的临床应用效果。方法急性脑梗死患者中抽取69例为研究对象,对其分别实施CT脑灌注与血管造影检测,分析平扫及灌注成像表现,对比缺血区与脑血流参数与其对侧相应区域灌注参数,进行脑内动脉、颈段血管造影图像的重建。结果 (1)经头颅平扫显示有早期脑梗死征象者41例,无灌注异常区域28例。经CT脑灌注成像检查显示,患者脑梗死区的血流量、脑血容量均明显低于对侧镜像区,其中梗死区域对侧镜像区的血流量对比差异均有统计学意义(P0.01),而脑血容量对比差异无统计学意义(P0.05);(2)脑梗死区对比剂峰值时间与对比剂平均通过时间均明显长于对侧镜像区(均P0.01);(3)患者的血管造影图重建结果显示,单侧颈内动脉狭窄37例,单侧大脑动脉狭窄16例,左侧大脑动脉闭塞11例,左侧颈内动脉闭塞5例。结论 CT脑灌注可准确并及时反应患者脑部缺血程度、缺血位置,并预测其半暗带,而脑部血管造影可反映其病变血管位置、病变程度,联合应用CT脑灌注与血管造影检测法有助于早期、准确诊断急性脑梗死。     

64层螺旋CT脑灌注联合CT血管造影对颈内动脉狭窄或闭塞的诊断价值

目的探讨64层螺旋CT脑灌注联合CT血管造影对颈内动脉狭窄或闭塞的诊断价值。方法选取因颈内动脉狭窄或闭塞在我院进行治疗的80例患者,对其进行64层螺旋CT脑灌注、CT血管造影扫描。观察64层螺旋CT脑灌注的平均通过时间、对比脑血流量、脑血容量、对比剂峰值时间,观察血管造影后患者的劲内动脉狭窄程度。结果短暂性脑缺血发作、急性脑梗死患者患侧的对比剂峰值时间均明显长于健侧的对比剂峰值时间,差异有统计学意义(P<0.05)。结论采用64层螺旋CT脑灌注联合CT血管造影,能同时诊断颈内动脉狭窄或闭塞的脑部血流灌注及颈动脉狭窄的程度。     

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。     

CT脑灌注与血管造影在急性脑梗死中的临床应用

目的研究CT脑灌注与血管造影在急性脑梗死中的临床应用价值。方法对34例急性脑梗死患者行CT平扫、CT脑灌注和血管造影检查,观察成像,与对侧健区进行比较,重建血管造影图像,治疗后行CT复查。结果 CT平扫发现同临床症状相对应的病灶比例为76.47%;CT脑灌注显示血流量降低;病变区的脑容量同对侧健区的脑容量差异无统计学意义(P0.05),脑血流量低于对侧健区;对比峰值时间和对比剂平均通过时间病变区均高于对侧健区(P0.05);血管造影显示患者均存在颈内动脉闭塞或狭窄现象。结论对急性脑梗死采用CT脑灌注与血管造影可以准确显示病变区的血管情况,可作为早期诊断的重要依据。     

CT灌注成像与经颅多普勒超声对后循环短暂性脑缺血发作的诊断价值

目的 探讨CT灌注成像、经颅多普勒超声对后循环短暂性脑缺血发作的诊断价值.方法 对42例后循环短暂性脑缺血发作的患者进行后循环CT灌注成像、经颅多普勒超声检查.结果 CT灌注成像显示低灌注者33例;经颅多普勒超声显示36例患者,共49条血管异常,其中血管狭窄VA 12条,BA 4条,动脉硬化VA 30条,BA 3条;TCD检查提示血管异常的36例患者中,CTPI检查提示低灌注32例.结论 CT灌注成像和经颅多普勒超声是筛选及早期发现血管病变部位的有效手段,利于TIA的诊断和治疗方案的选择.     

颅内血管狭窄与短暂性脑缺血早期发展为脑梗死的相关性

目的研究颅内血管狭窄与短暂性脑缺血早期发展为脑梗死的相关性。方法收集128例于我院确诊为短暂性脑缺血的患者,通过颅脑磁共振弥散加权成像(DWI)判断患者住院1周内有无新鲜脑梗死及计算转化为脑梗死的百分率。通过头颈CT血管造影(CTA)检查所有患者颅内血管的狭窄程度、狭窄数量以及狭窄部位,分析颅内血管异常与短暂性脑缺血转化为脑梗死的相关性。结果 128例短暂性脑缺血患者发展为早期脑梗死的发生率为29.68%,短暂性脑缺血患者的血管狭窄程度与短暂性脑缺血后早期脑梗死发生率呈正相关(P0.001),责任血管狭窄患者的短暂性脑缺血后早期脑梗死发生率显著高于非责任血管狭窄患者(P=0.002);动脉近端狭窄患者的短暂性脑缺血后早期脑梗死发生率显著高于动脉远端狭窄患者(P0.001),颅内动脉狭窄数量与短暂性脑缺血后早期脑梗死发生率相关(P0.001)。结论颅内血管狭窄是短暂性脑缺血早期发展为脑梗死的独立危险因素,通过头颈CT血管造影检查有利于评估短暂性脑缺血患者早期发展为脑梗死的风险。     

急性缺血性脑血管病76例多模式CT影像学分析

目的探讨76例急性缺血性脑血管病(AICVD)的多模式CT影像学特点。方法采用320排多层螺旋CT对76例AICVD(发病时间24h)患者急诊进行CT平扫(NCCT)+CT灌注成像(CTP)+CT血管成像(CTA)一站式扫描检查,分析灌注区脑血流量(CBF)、脑血容量(CBV)、平均通过时间(MTT)、达峰时间(TTP)等灌注参数变化及CT血管成像(CTA),并于入院后3d内行头颅MRI,评估其脑灌注特点及血管影像。结果在获取的76例CTP数据中,通过感兴趣区识别划分筛查,有59例患者有明确的异常CTP,有17例患者未发现明确感兴趣区。59例异常CTP中包括急性脑梗死47例,短暂性脑缺血发作(TIA)12例。急性脑梗死患者异常CTP特点:发病在4.5h以内的4例患者CTP表现为患侧CBF均较健侧下降,CBV正常或者轻度增高,MTT、TTP延长;发病时间在4.5~6h内的4例:其中2例CTP表现为CBF降低,CBV正常,MTT、TTP延长,2例表现为CBF降低,CBV轻度降低,MTT、TTP延长;发病时间在6~24h内的39例:其中30例梗死区与CTP异常脑灌注区部位一致,均表现CBF明显降低,CBV明显降低,MTT、TTP延长;12例TIA患者CTP均发现与临床症状相对应的灌注异常:MTT、TTP延长,CBF正常或减低,CBV升高。CTA发现责任动脉重度狭窄5例,血管闭塞10例,7例可见血流缓慢,排空延迟及侧支血管形成。结论多模式CT能够对AICVD提供血流灌注参数的变化及血管情况、供血区的血流动力学变化,对临床诊治具有一定参考价值,主要用于评估大脑半球卒中,多模式CT有临床价值。     

Advanced CT imaging (functional CT).

Computed tomography can provide anatomic and functional information about the brain. The conventional CT of the brain can be coupled with a cerebral blood flow examination using the stable xenon CT technique and with a CT angiography. Distinct subgroups of patients based on variations in cerebral blood flow and vascular pathology have been demonstrated. The addition of the functional information has become extremely important in triaging and determining the appropriate intervention in the patient with an acute neurological deficit.     

Fetal CT

Introduction Fetal CT is helpful in the diagnosis of bony anomalies, particularly with 3D reconstructions.Discussion Because of the potential risks of irradiation, CT should not be performed before 32 weeks' gestation and should be restricted to a carefully selected group of patients.     

脑CT灌注成像联合CT血管成像在超急性期脑梗死中的应用

目的 评价CT平扫、CT灌注成像(CTPI)与CT血管成像(CTA)相结合的技术在超急性期脑梗死(HCI)中的应用.方法 对21例HCI患者行CT、CTPI和CTA检查,对比观察CT、CTPI和CTA图像,分析最终病灶大小与CTPI和CTA的关系.结果 21例脑梗死患者均于发病6h内就诊.CT平扫仅于4例中见早期表现;CTPI在20例中发现灌注异常;CTA在16例中显示异常.结论 CTPI联合CTA能够在超早期有效地诊断脑梗死.     

Processing and interpretation times of CT angiogram and CT perfusion in stroke

OBJECTIVE: To determine the mean time for acquiring computed tomogram perfusion (CTP) and CT angiogram (CTA) images in acute stroke. To determine and compare processing and interpretation times amongst three groups of radiologists with varying degree of expertise: two radiology residents (Group I), two neuroradiology fellows (Group II) and four consultant neuroradiologists (Group III). METHODS: The mean time of acquisition of CTA and CTP studies was calculated among ten patients presenting with acute stroke. All readers had to process the CTA and CTP images, interpret them (for presence or absence of thrombus and penumbra) and save them on the GE Advantage Windows workstation. The mean time for processing and interpreting these studies was calculated. RESULTS: The mean time for acquisition of CTA and CTP studies in the ten patients was 14.6 +/- 5.9 minutes. The time taken for CTA processing and interpretation in Groups I, II and III was 2.3 +/- 1.3 min, 1.6 +/- 0.4 min and 1.5 +/- 0.7 min respectively. The time required for CTP processing and interpretation by the same groups was 5.2 +/- 1.7 min, 4.5 +/- 1.5 min and 4.1 +/- 1.1 min respectively. There was a statistically significant difference of means between Groups I and III in the CTA and CTP processing and interpretation times (p=0.02, p=0.01 respectively) but no statistical difference between Groups I and II (p=0.15, p=0.22 respectively) or Groups II and III (p=0.31, p=0.30 respectively). CONCLUSION: The CTA and CTP studies can be performed, processed and interpreted quickly in acute stroke.     

Incidence of contrast nephropathy from cerebral CT angiography and CT perfusion imaging

The incidence of contrast-induced nephropathy was examined in 1,075 patients receiving routine CT angiography and CT perfusion brain imaging at a single institution. Fifty-two patients had a creatinine rise of > or =0.5 mg/dL. In four patients (0.37%), the administration of IV contrast medium possibly contributed to renal failure. Two patients (0.19%) received temporary hemodialysis during hospitalization. The incidence of contrast nephropathy in neurovascular patients is low.     

Diagnosing Brain Death by CT Perfusion and Multislice CT Angiography

Introduction

Although the diagnosis of brain death (BD) is usually based on clinical criteria, in sedated patients, ancillary techniques are needed. This study was designed to assess the accuracy of cerebral multislice computed tomographic angiography (CTA) and CT perfusion (CTP) in diagnosing BD.

Methods

Prospective observational study in 27 BD patients.

Results

All patients were diagnosed as BD based on clinical and electroencephalogram findings. After BD diagnosis, CTP was performed followed by 64-detector multislice CTA from the aortic arch to the vertex. Images were reconstructed from 0.5 mm sections. In 24 patients, a lack of cerebral blood flow (CBF) was detected by CTP, and CTA revealed luminal narrowing of the internal carotid artery in the neck and absence of anterior and posterior intracranial circulation (sensitivity 89%). CTA detected CBF exclusively in extracranial portions of the internal carotid and vertebral arteries. Two patients with anoxic brain injury and decompressive craniectomy showed CBF in the CTA such that the CTP results were considered false negatives, given BD had been confirmed by clinical and EEG findings, along with evoked potentials. In one clinically BD patient, in whom an alpha rhythm was detected in the electroencephalogram, CBF was only observed in the intracranial internal carotid with no posterior circulation noted. This patient was therefore considered exclusively brain stem dead.

Conclusions

The radiological protocol used shows a high sensitivity and excellent specificity for detecting the cerebral circulatory arrest that accompanies BD. As a rapid, non-invasive, and widely available technique it is a promising alternative to conventional 4-vessel angiography.