多种CT影像诊断急性缺血性脑血管病的优势

doi:10.3969/j.issn.1673-5374.2013.07.010

摘要/Abstract

摘要：

对发病6h内的34例脑梗死患者及18例短暂性脑缺血发作患者依次行多层螺旋CT平扫，CT灌注成像及CT血管成像检查。CT灌注成像显示脑梗死组和短暂性脑缺血发作组分别有29例和10例患者出现与临床症状相对应的血流灌注异常。CT血管成像发现41例患者有不同程度与临床症状相对应的血管狭窄，脑梗死组33例、短暂性脑缺血发作组8例，其中颅内动脉狭窄发生率高于颅外动脉，主要位于颅内的大脑中动脉主干及颈内动脉虹吸部，颅外的颈总动脉分叉处和椎动脉开口处。CT血管成像发现责任血管，同时CT灌注成像异常患者34例(83％)；而CT血管成像未发现责任血管，但CT灌注成像异常患者5例(45%)。同时临床神经功能缺损程度评分≥5分的患者脑梗死发生率明显高于＜5分者。说明多种CT影像联合应用能够早期诊断急性缺血性脑血管病，并可以从形态和功能学上综合分析急性缺血性脑血管病的病因和程度。

关键词: 神经再生, 神经影像, 多层螺旋CT, CT灌注成像, CT血管成像, 缺血性脑血管疾病, 诊断, 脑梗死, 短暂性脑缺血发作, 血流灌注, 神经功能缺损, 基金资助文章, 图片文章

Abstract:

Thirty-four patients with cerebral infarction and 18 patients with transient ischemic attack were examined by multi-slice spiral CT scan, CT perfusion imaging, and CT angiography within 6 hours after onset. By CT perfusion imaging, 29 cases in the cerebral infarction group and 10 cases in the transient ischemic attack group presented with abnormal blood flow perfusion, which corresponded to the clinical symptoms. By CT angiography, various degrees of vascular stenosis could be detected in 41 patients, including 33 in the cerebral infarction group and eight in the transient ischemic attack group. The incidence of intracranial artery stenosis was higher than that of extracranial artery stenosis. The intracranial artery stenosis was located predominantly in the middle cerebral artery and carotid artery siphon, while the extracranial artery stenosis occurred mainly in the bifurcation of the common carotid artery and the opening of the vertebral artery. There were 34 cases (83%) with convict vascular stenosis and perfusion abnormalities, and five cases (45%) with perfusion abnormalities but without convict vascular stenosis. The incidence of cerebral infarction in patients with National Institutes of Health Stroke Scale scores ≥ 5 points during onset was significantly higher than that in patients with National Institutes of Health Stroke Scale scores < 5 points. These experimental findings indicate that the combined application of various CT imaging methods allows early diagnosis of acute ischemic cerebrovascular disease, which can comprehensively analyze the pathogenesis and severity of acute ischemic cerebrovascular disease at the morphological and functional levels.

Key words: neural regeneration, neuroimaging, clinical practice, multi-slice spiral CT, CT perfusion imaging, CT angiography, ischemic cerebrovascular disease, diagnosis, cerebral infarction, transient ischemic attack, perfusion, neurological function deficit, grants-supported paper, photographs-containing paper, neuroregeneration

. 多种CT影像诊断急性缺血性脑血管病的优势[J]. 中国神经再生研究(英文版), 2013, 8(7): 655-661.

Gang Wang, Xue Cheng, Xianglin Zhang. Use of various CT imaging methods for diagnosis of acute ischemic cerebrovascular disease[J]. Neural Regeneration Research, 2013, 8(7): 655-661.

参考文献

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引言

表1 美国国立卫生研究院卒中量表（ NIH Stroke Scale，NIHSS ）

项目	评分标准
1a.意识水平：即使不能全面评价（如气管插管、语言障碍、气管创伤及绷带包扎等），检查者也必须选择1个反应。只在患者对有害刺激无反应时（不是反射）才能记录3分。	0 清醒，反应灵敏 1 嗜睡，轻微刺激能唤醒，可回答问题，执行指令 2 昏睡或反应迟钝，需反复刺激、强烈或疼痛刺激才有非刻板的反应 3 昏迷，仅有反射性活动或自发性反应或完全无反应、软瘫、无反射
1b.意识水平提问：月份、年龄。仅对初次回答评分。失语和昏迷者不能理解问题记2分，因气管插管、气管创伤、严重构音障碍、语言障碍或其他任何原因不能完成者（非失语所致）记1分。可书面回答。	0 两项均正确 1 一项正确 2 两项均不正确
1c.意识水平指令：睁闭眼；非瘫痪侧握拳松开。仅对最初反应评分，有明确努力但未完成的也给分。若对指令无反应，用动作示意，然后记录评分。对创伤、截肢或其他生理缺陷者，应予适当的指令。	0 两项均正确 1 一项正确 2 两项均不正确
2.凝视：只测试水平眼球运动。对随意或反射性眼球运动记分。若眼球偏斜能被随意或反射性活动纠正，记1分。若为孤立的周围性眼肌麻痹记1分。对失语者，凝视是可以测试的。对眼球创伤、绷带包扎、盲人或有其他视力、视野障碍者，由检查者选择一种反射性运动来测试，确定眼球的联系，然后从一侧向另一侧运动，偶尔能发现部分性凝视麻痹。	0 正常 1 部分凝视麻痹（单眼或双眼凝视异常，但无强迫凝视或完全凝视麻痹） 2 强迫凝视或完全凝视麻痹（不能被头眼反射克服）
3.视野：若能看到侧面的手指，记录正常，若单眼盲或眼球摘除，检查另一只眼。明确的非对称盲（包括象限盲），记1分。若全盲（任何原因）记3分。若频临死亡记1分，结果用于回答问题11。	0 无视野缺损 1 部分偏盲 2 完全偏盲 3 双侧偏盲（包括皮质盲）
4.面瘫：	0 正常 1 轻微（微笑时鼻唇沟变平、不对称） 2 部分（下面部完全或几乎完全瘫痪） 3 完全（单或双侧瘫痪，上下面部缺乏运动）
5、6.上下肢运动：置肢体于合适的位置：坐位时上肢平举90^o，仰卧时上抬45^o，掌心向下，下肢卧位抬高30^o，若上肢在10秒内，下肢在5秒内下落，记1～4分。对失语者用语言或动作鼓励，不用有害刺激。依次检查每个肢体，从非瘫痪侧上肢开始。	上肢： 0 无下落，置肢体于90^o （或45^o ）坚持10秒 1 能抬起但不能坚持10秒，下落时不撞击床或其他支持物 2 试图抵抗重力，但不能维持坐位90^o或仰位45^o 3 不能抵抗重力，肢体快速下落 4 无运动 5 截肢或关节融合，解释： 5a左上肢；5b右上肢
	下肢： 0 无下落，于要求位置坚持5秒 1 5秒末下落，不撞击床 2 5秒内下落到床上，可部分抵抗重力 3 立即下落到床上，不能抵抗重力 4 无运动 5 截肢或关节融合，解释： 6a 左下肢； 6b右下肢
7．肢体共济失调：目的是发现一侧小脑病变。检查时睁眼，若有视力障碍，应确保检查在无视野缺损中进行。进行双侧指鼻试验、跟膝径试验，共济失调与无力明显不呈比例时记分。若患者不能理解或肢体瘫痪不记分。盲人用伸展的上肢摸鼻。若为截肢或关节融合记9分，并解释。	0 无共济失调 1 一个肢体有 2 两个肢体有，共济失调在：右上肢1=有，2=无 3 截肢或关节融合，解释：左上肢1=有，2=无 4 截肢或关节融合，解释：右上肢1=有，2=无 5 截肢或关节融合，解释：左下肢1=有，2=无 6 截肢或关节融合，解释：右下肢1=有，2=无
8．感觉：检查对针刺的感觉和表情，或意识障碍及失语者对有害刺激的躲避。只对与脑卒中有关的感觉缺失评分。偏身感觉丧失者需要精确检查，应测试身体多处[上肢（不包括手）、下肢、躯干、面部]确定有无偏身感觉缺失。严重或完全的感觉缺失记2分。昏睡或失语者记1或0分。脑干卒中双侧感觉缺失记2分。无反应或四肢瘫痪者记2分。昏迷患者（1a=3）记2分。	0 正常 1 轻-中度感觉障碍，（患者感觉针刺不尖锐或迟钝，或针刺感缺失但有触觉） 2 重度-完全感觉缺失（面、上肢、下肢无触觉）
9．语言：命名、阅读测试。若视觉缺损干扰测试，可让患者识别放在手上的物品，重复和发音。气管插管者手写回答。昏迷者记3分。给恍惚或不合作者选择一个记分，但3分仅给不能说话且不能执行任何指令者。	0 正常 1 轻-中度失语：流利程度和理解能力部分下降，但表达无明显受限 2 严重失语，交流是通过患者破碎的语言表达，听者须推理、询问、猜测，交流困难 3 不能说话或者完全失语，无言语或听力理解能力
10．构音障碍：读或重复表上的单词。若有严重的失语，评估自发语言时发音的清晰度。若因气管插管或其他物理障碍不能讲话，记9分。同时注明原因。不要告诉患者为什么做测试。	0 正常 1 轻-中度，至少有些发音不清，虽有困难但能被理解 2 言语不清，不能被理解，但无失语或与失语不成比例，或失音 3 气管插管或其他物理障碍，解释：
11．忽视：若患者严重视觉缺失影响双侧视觉的同时检查，皮肤刺激正常，记为正常。若失语，但确实表现为对双侧的注意，记分正常。视空间忽视或疾病失认也可认为是异常的证据。	0 正常 1 视、触、听、空间觉或个人的忽视；或对一种感觉的双侧同时刺激忽视 2 严重的偏侧忽视或一种以上的偏侧忽视；不认识自己的手；只能对一侧空间定位

材料方法

Design
A clinical observation focused on the neuroimaging.

Time and setting
Experiment was performed in January 2012 at the First Affiliated Hospital of Liaoning Medical University, China.

Subjects
A total of 52 patients with acute ischemic cerebrovascular disease were recruited from the First Affiliated Hospital of Liaoning Medical University, China between August 2009 and October 2011 (29 males and 23 females). The patient age range was 45–83 years (64 ± 13 years). All cases had stroke-associated clinical symptoms and signs, and a diagnosis consistent with the Diagnostic Criteria for Cerebrovascular Disease formulated by the Fourth National Conference of Chinese Medical Association in 1995[19], including: (1) acute onset; (2) recurrent episodes of vertigo or dizziness in the middle-aged or elderly, due to head position or posture changes; each episode lasts for a few minutes to 1 hour, and symptoms and signs disappear within 24 hours; (3) motion and sensation disorders; (4) vision loss in single or double eyes; and (5) excluding other diseases such as otogenic vertigo.

Inclusion criteria were: (1) all patients underwent CT scan within 6 hours after acute stroke onset, followed by CT perfusion imaging. CT angiography after intracranial hemorrhage was excluded and no responsible lesions were found. Patients and their relatives gave informed consent; (2) neurological impairment was evaluated by the National Institutes of Health Stroke Scale; and (3) there were 1–8 days duration between the first CT examination and follow-up CT examination.
Exclusion criteria were: (1) intracranial hemorrhage patients; (2) patients with hemorrhage disease, hemorrhagic diathesis, cardiac insufficiency, severe liver disease, hyperthyroidism, or hypothyroidism; and (3) pregnant patients.

The study was in accordance with the ethical requirements in Declaration of Helsinki.

Methods
“One-stop” multi-slice spiral CT scan
One-stop detection of CT scan, CT perfusion imaging, and CT angiography was performed using the GE Light speed 16 MSCT (Bethesda, MD, USA). Scanning parameters of CT scan were: starting at canthomeatal line, 120 kV voltage, 250 mA current, slice thickness 5 mm, layer space 5 mm, matrix 512 × 512, and field of view 23 cm. Scanning parameters of CT perfusion imaging were: the basal ganglia used as region of interest, “Toggling-table” technology, cine scanning mode[20], scan speed 1 layer/s, 80 kV voltage, 200 mA current, slice thickness 5 mm, time interval 0.5 second, scanning time 50 seconds, and delay time 8 seconds. A 40 mL of nonionic contrast agent iohexol (100 mL: 35 g iodine; Hokuriku Industry, Beijing, China) was injected (4.0 mL/s) using a high-pressure syringe via the elbow vein, and a synchronous dynamic scanning was performed when contrast agent injection began. At 10 minutes after CT perfusion imaging scan, a CT angiography scanning was performed at 120 kV voltage and 250 mA current; 100 mL of contrast agents were injected at 4 mL/s speed, with a delay of 18–23 seconds. The scanning ranged was from the head to the carotid artery.

Data processing
Data were processed on the ADW4.2 workstation (GE Medical System, Milwaukee, WI, USA) using the Perfusion 3.0 software package. The cerebral blood flow, cerebral blood volume, contrast agent mean transit time, and time to peak at the region of interest and the contralateral side were measured. Post-processing technology including multiple planar reconstruction, curved planar reconstruction, maximum intensity projection, and volume rendering, was applied to reconstruct and analyze the head and neck arteries and to measure the stenosis diameter in the carotid artery. The measuring level was perpendicular to the vascular major axis, and the diameter of the normal blood vessels at both ends of the stenosis vessels served as controls. According to the North American Symptomatic Carotid Endarterectomy Trial, the degree of stenosis was divided into four grades: I, mild stenosis (0–29%); II, moderate stenosis (30–69%); III, severe stenosis (70–99%); and IV, occlusion (100%)^[21].

National Institutes of Health Stroke Scale scores
Prior to CT examination, patients were assessed with the National Institutes of Health Stroke Scale. Patients were not forced to train, such as repeatedly performing a task. Higher scores indicated more severe neurological impairment[22] (supplementary Table 1 online).

Statistical analysis
All data were analyzed using SPSS 11.5 software (SPSS, Chicago, IL, USA). Measurement data are expressed as mean ± SD, and statistical comparisons were performed using two-sample t-test of a paired design and a group design. Count data were analyzed using the chi-square test. A P value less than 0.05 was regarded of significantly different.

Acknowledgments: We thank Jinglan Gao and Kejian Wu from the Department of Radiology in the First Affiliated Hospital of Liaoning Medical University for multi-slice spiral CT scanning technology, and Na Xu for data collection and clinical trials.
Funding: This study was supported by the Youth Fund of the First Clinical College of Liaoning Medical University, No. 2010C20.
Author contributions: Gang Wang was responsible for the funds, study concept and design, data analysis and statistical processing, and manuscript writing. Xue Cheng provided technical and information support, and experimental data. Xianglin Zhang instructed the study and supervised the paper. All authors had read and approved the final version of the manuscript submitted.
Conflicts of interest: None declared.
Ethical approval: This study is approved by the Ethics Committee in the First Clinical College of Liaoning Medical University in China.
Author statements: The manuscript is original, has not been submitted to or is not under consideration by another publication, has not been previously published in any language or any form, including electronic, and contains no disclosure of confidential information or authorship/patent application/funding source disputations.
Supplementary information: Supplementary data associated with this article can be found, in the online version, by visiting www.nrronline.org.

讨论

文章快阅

延伸阅读

1实验设计构思介绍：

短暂性脑缺血发作及脑梗死是临床上缺血性脑血管病的主要类型。很多短暂性脑缺血发作患者因为存在较为严重的血管狭窄或闭塞，最终会发生完全性的脑卒中，所以必须早期诊断、早期治疗。脑梗死是神经系统常见病、多发病，迄今为止，除时间窗内的溶栓治疗外，尚无其他特效治疗。经典的溶栓时间窗为发病后3～6 h，溶栓的关键是抢救缺血半暗带，很多研究表明，经典时间窗内的患者不一定都存在缺血半暗带，相反，时间窗以外的部分患者却存在缺血半暗带。近年来，随着多层螺旋CT的出现，CT灌注成像和CT血管成像在早期缺血性脑血管病诊断中的应用，引起了人们越来越多的关注，因此，实验采用MSCT平扫、CT灌注成像及CT血管成像“一站式”检查方法，探讨其在急性缺血性脑血管病中的应用价值。

2 国内外同类研究水平的介绍：

目前，临床上用于组织血流灌注的功能性成像检查方法较多，如正电子发射体层成像、单光子发射体层成像、氙CT、磁共振波谱、弥散和MR灌注成像等。由于这些检查设备比较昂贵，有的还需特殊装备，成像时间较长，在一定程度上限制了其推广与普及。而CT灌注成像具有经济实用、扫描设备简单、检查时间短(仅需数分钟)、图像的空间分辨率高，并能获得脑血流量、峰值时间、对比剂通过时间等多个脑血流动力学参数等优点，可在急性缺血性脑血管疾病的超早期发现病灶，相对脑血流量减少是其最显著的改变，相对脑血流量像在显示缺血性区域方面已被证实为有效和可靠的方法。CT血管成像肘静脉给药，创伤小，可以避免数字化血管造影创伤性检查造成的血管痉挛、动脉硬化斑块脱落等并发症，易为患者接受。CT血管成像同时显示全脑多支血管，可任意旋转多方位观察，有利于血管状态的显示，克服了数字化血管造影投射角度局限性的缺点。最大强度投影对钙化的显示比数字化血管造影敏感。数字化血管造影空间分辨率高，目前仍被作为金标准，对显示细小血管优于CT血管成像。总之，CT灌注成像联合CT血管成像检查安全、经济、简便、快捷，发病后即可进行。CT灌注成像早期显示急性脑缺血病灶的范围并能获得脑血流量、脑血容量、峰值时间等多个脑血流动力学参数，定量分析脑组织血流灌注状态。CT血管成像可多方位动态观察脑血管，清楚地显示脑供血动脉的形态变化及引起脑缺血的其他原因。总之，CT灌注成像联合CT血管成像检查可在短暂性脑缺血发作疾病诊断中对患者进行颅脑CT平扫、CT灌注成像、CT血管成像检查及CT增强扫描，获得多方面的信息从多个角度对其进行综合评价分析，可为临床医师选择合理的治疗方法尽早进行治疗，提供客观的影像依据。

3与其他同类研究的比较：

多层螺旋CT“一站式”检查应用简单、快速、准确、经济，无明显副作用,易于推广，10-15 min内就可完成3项扫描，特别适用于急诊；一次检查即可获得普通CT平扫、增强扫描、脑血流灌注成像、脑血管情况等多方面信息的优势。CT灌注成像显示与神经系统损害相对应的脑组织局部灌注异常区，CT血管成像显示相应的动脉血管狭窄的程度。它们联合应用可以有效评估脑缺血的血流情况和动脉狭窄程度，为临床的治疗提供强有力的技术支持。通过此方法有助于明确脑缺血患者的发病部位和性质、血管状况、有无可挽救的脑组织等，从而对下一步的治疗决策、评价疗效和预后评估提供依据，节约宝贵的治疗时间。

4 本文先进性：

检索Pubmed数据库，检索时间为2012-01，检索时间范围1998/2012，检索关键词为：computed tomography，perfusion imaging；angiograph；ischemic cerebrovascular disease。检出相关文章：218篇。

5 专家意见与答疑

专家意见：本文章的研究内容在国内外已有相关研究，并且临床观察例数远多于本研究例数。

作者答疑：国内外关于急性脑血管病CT灌注的研究较多，但是，本实验在此基础上将多种CT检查方法结合，并密切结合临床神经功能缺损程度评分及血管狭窄的部位和程度，“一站式”完成CT所有检查，国内外尚未见相关报导。由于前来就诊的患者大多数发病时间已超过6h，故收集病例数相对较少，后续实验将继续补充，并进行深入研究。