三维可变翻转角快速自旋回波成像技术在颈动脉高分辨磁共振成像中的应用

目的 探讨三维T2可变翻转角加权快速自旋回波成像技术（three dimensional-T2 weighted imagingsampling perfection with application optimized contrasts using different flip angle evolutions,3D-T2WISPACE） 序列在颈动脉高分辨率磁共振成像中的应用价值。 方法 收集临床怀疑颈动脉病变患者30例,进行高分辨多对比颈动脉磁共振成像（m a g n eti c resonance imaging,MRI）,行冠状位3D-T2WI-SPACE序列并应用3D后处理软件进行斜矢状位和轴位重 建。比较3D-T2WI-SPACE序列和横轴位黑血T2WI序列的信噪比及图像质量,并对图像成像范围、对病 变诊断信息提供的充分程度进行比较。 结果 60支颈动脉中,正常13支,病变47支。其中颈动脉粥样硬化病变44支,颈动脉夹层1支,不明 原因的特发性狭窄2支。30例病例图像质量评价中,3D-T2WI-SPACE序列图像质量2级5例,3级25 例;T2WI序列图像质量2级4例,3级26例。3D-T2WI-SPACE序列对诊断信息提供的充分程度略优于 高分辨T2WI。3D-T2WI-SPACE序列与高分辨率T2WI图像的覆盖范围分别为（114.7±22.4）mm和46 mm。 3D-T2WI-SPACE序列图像与高分辨T2WI的信噪比平均值分别为15.7±3.5及22.7±14.7,差异无显著性 （P =0.163）。 结论 3D-T2WI-SPACE技术可作为颈动脉高分辨成像序列中的必要辅助序列。应用3D-T2WI-SPACE 序列结合重建技术,可为临床诊断提供更多信息。     

磁敏感加权成像在苍白球内侧核脑深部电刺激术中的应用价值

目的 评价磁敏感加权成像（susceptibility-weighted imaging,SWI）对帕金森病病人苍白球内侧核（globus pallidus interna,Gpi）的定位价值。方法 回顾性分析37例行脑深部电刺激术（deep brain stimulation,DBS）帕金森病病人的临床资料,均行3.0T MRI SWI、T2WI和T1WI序列检查。分别测量不同序列中Gpi与周围脑白质的对比度（contrast ratio,CR）及对比噪声比（contrast-to-noise ratio,CNR）,并由有经验的影像医师对图像质量进行评分,统计比较3组序列的CR、CNR和图像质量评分。结果 3组序列间Gpi图像质量评分差异有统计学意义（χ~2=48.708,P=0.000）;经两两比较,SWI序列成像效果最佳,T2WI序列次之,T1WI序列最差。3组序列间CR (F=149.451,P=0.000）、CNR (F=91.836,P=0.000）差异均有统计学差异。结论相较于常规T2WI和T1WI,SWI序列可提高MRI对Gpi的显示能力,在DBS手术Gpi精确定位中具有广阔的应用前景。     

颅内动脉粥样硬化三维流动散相磁共振成像的可行性

【摘要】 目的 探讨使用三维流动散相磁共振成像技术进行颅内动脉粥样硬化斑块成像的可行性。 方法 在3.0T磁共振扫描仪上对10例经数字减影血管造影证实症状性颅内动脉狭窄程度>70%的患者进行颅内动脉斑块成像,扫描序列包括三维流动散相准备的梯度回波成像序列（three dimensional flow-dephasing-prepared fast spoiled gradient recalled echo,3D FDP-FSPGR）和二维双反转恢复序列（two dimensional double inversion recovery,2D DIR）,比较两个序列所得图像的对比噪声比、管腔面积与斑块面积测量结果。 结果 3D FDP-FSPGR和2D DIR图像的对比噪声比分别为10.16±4.28和14.81±5.26,差异无显著性（t =2.03,P >0.05）。测量3D FDP-FSPGR和2D DIR图像的狭窄处管腔面积分别为2.2±1.2 mm2和2.2±1.3 mm2,斑块面积分别为18.8±1.4 mm2和18.5±0.9 mm2,均具有较好的一致性（管腔面积组间相关系数＝0.96,斑块面积组间相关系数＝0.95）。2D DIR成像范围8 mm,扫描时间4.8 min,3D FDPFSPGR成像范围48 mm,扫描时间3.7 min。 结论 与2D DIR相比,3D FDP-FSPGR可在较短时间内获取大范围颅内动脉主干的三维管壁图像,图像质量可以满足临床需求,成像技术可靠,能为临床制订治疗方案提供更全面准确的影像学依据。     

大脑中动脉粥样硬化狭窄斑块的高分辨率磁共振管壁成像

目的探讨高分辨率磁共振(HR-MRI)管壁成像技术评价大脑中动脉粥样硬化狭窄斑块的临床应用价值。方法对72例患者行3D-TOF和HR-MRI序列(包括T2WI、T1WI和增强T1WI)的扫描。分析斑块所在的位置及定性地将斑块分为等、高、低和混杂信号4类,并定量测量斑块强化率。比较非急性卒中组和急性卒中组MCA斑块的上述形态学特征。结果最终纳入本研究的72例狭窄患者中,非急性卒中组44例,急性卒中组28例。管壁成像显示,急性卒中组的混杂信号斑块明显多于非急性卒中组(P<0.0001);斑块强化率在急性卒中组中也较高(P=0.0218)。结论高分辨率MRI技术可无创性的评估大脑中动脉粥样硬化斑块疾病,综合考虑斑块强化率及混杂信号两个因素可以提高对急性卒中的预测价值,并对制定临床治疗策略提供帮助。     

高分辨MRI对颈动脉粥样硬化斑块成分显示的病理对照研究

目的分析和评价高分辨MRI对颈动脉粥样硬化斑块不同成分的显示效果,为颈动脉内膜切除术术前判断斑块稳定性提供参考。方法对26例行颈动脉内膜切除术的颈动脉粥样硬化性狭窄患者术前高分辨MRI 4种不同序列的影像(T1WI、T2WI、PDWI和3D TOF)与斑块标本病理进行逐层对照,分析斑块内不同成分的MRI影像特点。结果获得斑块28块,切为238段,主要分布于颈总动脉和颈内动脉,以复杂斑块为特征的Ⅳ～Ⅴ型58段(24.37%)和Ⅵ型79段(33.19%)为主;斑块内纤维帽主要表现为TOF序列的带状低信号,钙化和纤维化组织分别表现为在各序列影像上的不规则低信号和不特定信号,脂质池和坏死核呈T1WI、PDWI和3D TOF序列的等至稍高信号,近期出血表现为T1WI、T2WI和PDWI序列的明显高信号。结论高分辨MRI不仅可以清晰显示动脉粥样硬化斑块,进行动脉管腔狭窄程度的测定,通过多序列影像联合分析还可以分辨斑块内部不同成分,有助于术前对斑块稳定性的判断。     

磁共振弥散成像在脑梗塞急性期诊断方面的价值

目的总结脑梗塞的磁共振弥散成像表现,非比较弥散成像技术与传统磁共振成像（MRI）技术（如MRT1WI、T2WI及FLAIR序列）在急性期脑梗塞诊断方面的差别,阐明弥散成像诊断急性期脑梗塞的优越性。方法应用基于平面回波成像（EPI）的弥散成像技术,并结合传统MR成像技术（如MRT1WI、T2WI及FLAIR序列）分析17例脑缺血发作2小时至2天病人图像特点。结果弥散成像最早在梗塞发生2小时发现病灶,表现为缺血区的局限性高信号影,边界清楚。发病时间在6小时以内者共7例（41.18％）,弥散成像均能清楚显示病灶,而传统MR成像技术本能显示;发作时间在6小时至2天者共10例（58．82％）,弥散成像和传统MR成像技术均能显示病灶,其中7例（70．00％）弥散成像显示的范围要大于同层面T2WI像。结论弥散成像在检测和定位急性期脑梗塞方面较为敏感,这对于指导临床治疗和促进预后均有很大的价值。     

磁敏感成像诊断颅内多发海绵状血管瘤的价值

目的：探讨磁敏感加权成像（SWI）对颅内多发海绵状血管瘤的诊断价值。方法：采用SWI序列并与常规MRI扫描序列进行对照,对5例颅内多发海绵状血管瘤患者进行扫描,分析MR不同扫描序列对颅内多发海绵状血管瘤图像的区别。结果：5例患者中T1WI发现海绵状血管瘤病灶15个,T2WI发现病灶37个,T2 FLAIR发现病灶53个,SWI发现病灶179个。结论：MR SWI序列在颅内多发海绵状血管瘤显示方面具有较高敏感性,尤其对于小病灶的检出,应将其列入颅内多发海绵状血管病常规检查。     

基于多对比度磁共振血管壁成像技术对前循环症状性颅内外动脉粥样硬化斑块特征的对比研究

目的 基于多对比度MRI血管壁成像技术,比较颅内动脉、颅外动脉粥样硬化斑块的特征。 方法 回顾经3D多对比度头颈联合MRI血管壁成像检查确定存在前循环症状性颅内外动脉粥样硬化 斑块的患者资料。观察斑块分布情况;测量斑块负荷,包括斑块最大管壁厚度、长度、管腔狭窄程度; 分析斑块内成分,包括脂质坏死核、出血、钙化,对比分析颅内动脉和颅外动脉粥样硬化斑块的影像 学特征。 结果 在入组的45例患者中,共检出颅内、外动脉粥样硬化斑块203个,其中颅外动脉斑块156 个（76.8%）,颅内动脉斑块47个（23.2%）。颅外动脉粥样硬化斑块最大管壁厚度（[ 3.2±1.0）mm vs （1.9±0.4）mm,P <0.001]、斑块长度[10.7（7.5～13.7）mm vs 4.3（2.6～6.3）mm,P <0.001]大于颅内动 脉,而颅内动脉管腔狭窄程度[28.0%（20.0%～38.5%）vs 18.8%（10.8%～30.5%）,P <0.001]重于颅外 动脉。颅外动脉粥样硬化斑块内脂质坏死核的发生率高于颅内动脉（66.0% vs 21.3%,P <0.001）,而 斑块内出血的发生率颅内动脉高于颅外颈动脉（27.7% vs 13.5%,P =0.027）。 结论 在合并有颅内外动脉粥样硬化斑块的患者中,颅外动脉的斑块最大管壁厚度、斑块内脂质 坏死核的发生率高于颅内动脉,而管腔狭窄程度、斑块内出血的发生率低于颅内动脉。     

磁敏感加权成像在脑海绵状血管瘤的定量分析

目的探讨磁敏感加权成像（SWI）序列对脑海绵状血管瘤诊断的敏感性,定量评价SWI序列较常规MRI序列及弥散加权成像（DWI）序列对脑海绵状血管瘤的诊断价值。方法回顾分析经临床及病理证实的27例脑海绵状血管瘤患者磁共振影像,对T1WI、T2WI、DWI及SWI序列在病灶检出数目、病灶面积方面进行测量。结果 T1WI检出病灶共31个,T2WI检出病灶35个,DWI检出病灶46个,SWI检出病灶106个。单个病灶最大面积：T1WI平均（0.80±0.38）cm^2,T2WI平均（0.96±0.43）cm^2,DWI平均（1.14±0.56）cm^2,SWI平均（1.43±0.61）cm^2。结果显示：SWI较T1WI、T2WI、DWI序列病灶检出数目多。在病灶面积显示方面,SWI序列明显优于T1WI、T2WI、DWI序列,且存在显著差异,P均〈0.05。结论SWI序列在检出脑海绵状血管瘤的病灶范围和数目方面明显优于T1WI、T2WI、DWI序列,具有重要临床应用价值。     

不同机制症状性颅内动脉粥样硬化性疾病的高分辨率磁共振特征

目的 探究不同机制大动脉粥样硬化型卒中患者颅内动脉粥样硬化斑块的特征是否存在差别。 方法 依据中国缺血性卒中亚型（Chinese Ischemic Stroke Subclassification,CISS）分型标准连续收录症 状性颅内动脉粥样硬化性疾病（symptomatic intracranial atherosclerotic stenosis,sICAS）患者作为研究 对象,并依据梗死机制将sICAS患者分组,无症状性ICAS患者作为对照组。对所有入组患者的责任动 脉管壁行高分辨率磁共振（high-resolution magnetic resonance imaging,HR MRI）扫描,比较不同机制 sICAS患者动脉粥样硬化斑块的特征。 结果 共有56例sICAS患者、9例无症状性ICAS患者纳入本研究。与无症状性ICAS患者比较,sICAS患者 颅内动脉粥样硬化斑块的特征表现为：病变局部正性重构率高、负性重构率低;动脉粥样硬化斑块 更多位于穿支动脉开口处。但不同机制sICAS患者颅内动脉粥样硬化斑块特征未发现明显差别。入组 患者中10例经经颅多普勒（transcranial Doppler,TCD）/磁共振血管成像（magnetic resonance angiography, MRA）检查未发现颅内动脉狭窄,经HR MRI检查发现存在粥样硬化斑块。 结论 HR MRI有助于发现sICAS患者不稳定斑块的存在,但不同机制sICAS患者颅内动脉粥样硬化斑 块的HR MRI特征差异无显著性。     

Intracranial internal carotid artery stenosis with vulnerable plaques successfully treated by stenting under cerebral protection

Percutaneous transluminal angioplasty with stenting (PTA/stenting) for intracranial atherosclerotic stenoses is usually performed without any protection devices. We report a unique case of atherothrombotic stenosis with the vulnerable plaque in the cavernous portion of the internal carotid artery (ICA), which was successfully treated by PTA/stenting under cerebral protection with the flow reversal system.A 68-year-old woman presented repetitive transient ischemic attacks in the right ICA territory. Cerebral angiography revealed 80% stenosis in the cavernous portion of the right ICA. High-resolution magnetic resonance imaging (HR-MRI) demonstrated lipid-rich plaques at this lesion. PTA/stenting was performed with a proximal protection device under flow reversal. A filter device captured much amount of atherothrombotic debris with lipid-rich macrophages and leukocytes, which was consistent with HR-MRI findings.Some selected cases of intracranial atherothrombotic ICA stenoses may need endovascular treatment with cerebral protection system. HR-MRI is useful to evaluate plaque characteristics even in the cavernous portion of the ICA.     

MRI findings in 32 consecutive lipomas using conventional and advanced sequences.

Intracranial lipomas are histologically benign and usually incidental magnetic resonance imaging findings that must be differentiated from ominous lesions. The authors describe 32 lipomas in 30 patients using conventional spin-echo (CSE) T1-weighted images (T1WI), CSE proton density (PDWI), CSE T2-weighted images (T2WI), fast spin-echo (FSE) T2WI, and FSE fluid-attenuated inversion recovery (FLAIR). Lipomas occurred most commonly in the trigonal choroid plexus, cerebral convexity, pericallosal, and quadrigeminal cistern regions. Lipomas were hyperintense on CSE T1WI and of variable appearance on CSE PDWI and CSE T2WI. Lipomas were isointense to hyperintense on FSE T2WI and hyperintense on FLAIR. Chemical shift artifact (CSA) usually was present on either CSE PDWI or CSE T2WI but was not seen on FSE images. One patient had intracranial hypotension associated with a large convexity lipoma. The authors conclude that lipomas appear different on CSE T2WI than on FSE T2WI. CSE PDWI and CSE T2WI are complementary in detecting CSA. The lack of CSA being detected in lipomas on FSE images most likely relates to inherent bandwidth differences compared with those of CSE. The hyperintense appearance of lipomas on FSE FLAIR and FSE T2WI may be confused with subacute hematomas. The authors recommend that if CSE technique by itself is used to exclude lipomas (in centers that are not using FSE), then T1WI, PDWI, and T2WI usually are sufficient. For centers using FSE routinely, fat saturation or CSE sequences also may be needed to exclude lipomas. Finally, the authors' series suggests that intracranial lipomas may occur in lateral locations more frequently than reported previously.     

Wall characteristics and mechanisms of ischaemic stroke in patients with atherosclerotic middle cerebral artery stenosis: a high-resolution MRI study

Objective:: To evaluate the characteristics of atherosclerotic middle cerebral artery (MCA) stenosis by high-resolution magnetic resonance imaging (HR-MRI) and determine the relationship between wall characteristics and infarction patterns.

Methods:: Thirty-six patients with acute ischaemic stroke due to MCA stenosis underwent diffusion-weighted magnetic resonance imaging (DWI) and HR MRI. Wall characteristics of MCA, including irregular surface, superior location, T2-hyperintense of plaques and positive remodelling (PR), were analysed. Characteristics of acute infarct on DWI were categorised according to the number (single or multiple infarcts) and the pattern of cerebral infarcts (cortical, border zone or perforating artery territory infarcts). The relationship between wall characteristics and infarction patterns was evaluated.

Results:: PR was observed in 20 patients, irregular surface plaque in 18 patients, superior location of plaques in 14 patients and T2-hyperintense foci in 13 patients. Seventeen patients had multiple acute cerebral infarcts and 13 showed single acute cerebral infarcts. Border zone infarcts were the most common (76.5%) among multiple acute infarcts. Penetrating artery infarcts (PAI) accounted for 76.9% of all single infarcts. Multiple infarcts were more frequently observed in patients with PR (P = 0.007) or plaque surface irregularity (P = 0.035). Single infarcts, especially PAI, were more prevalent in patients with superior plaque (P = 0.030). No statistically significant differences were observed between multiple and single infarcts in patients with T2-hyperintense lesions (P?=?0.638).

Conclusions:: PR or irregular surface plaques were associated with artery-to-artery embolism. Superior location of plaques was associated with PAI. HR-MRI provides insights into intracranial atherosclerosis in vivo, predictive of infarction patterns.     

颈动脉粥样硬化斑块与脑梗死关系的高分辨磁共振研究

目的探讨高分辨磁共振(MRI)对颈动脉粥样硬化斑块与脑梗死关系的评估价值。方法选取驻马店市精神病医院2014-01—2016-01收治的32例经高分辨MRI检查证实的脑梗死患者为试验组,以同期我院体检的行MRI扫描的25例无脑梗死患者作对照(对照组),采用三维时间飞跃法(3D-TOF)、T1加权(T1WI)、T2加权(T2WI)及增强颈部血管成像等扫描序列,分析颈动脉斑块的成分、分型及其与脑梗死的关系。结果试验组有颈动脉粥样硬化斑块者30例(93.75%),无颈动脉粥样硬化斑块者2例(6.25%);对照组有颈动脉粥样硬化斑块者6例(24.00%),无颈动脉粥样硬化斑块者19例(76.00%);试验组颈动脉粥样硬化斑块的发生率明显高于对照组(P0.01)。试验组共发现60块颈动脉粥样硬化斑块,其中Ⅰ~Ⅱ型7块(11.67%),Ⅲ型8块(13.33%),Ⅳ~Ⅴ型19块(31.67%),Ⅵ型21块(35.00%),Ⅶ型2块(3.33%),Ⅷ型3块(5.00%);对照组共发现14块颈动脉粥样硬化斑块,以稳定性斑块为主,Ⅰ~Ⅱ型13块(92.86%),Ⅳ型1块(7.14%)。2组颈动脉不稳定斑块发生率比较差异有统计学意义(P0.05)。脑梗死患者颈总动脉、分叉处及颈内动脉3个部位的粥样硬化斑块分布情况差异无统计学意义(P0.05)。结论高分辨MRI可清晰显示颈动脉粥样斑块的内部成分,且颈动脉粥样硬化斑块与脑梗死的发生有密切的相关性,高分辨MRI可对脑梗死的发生风险作出预测,为临床防治脑梗死及疗效评价提供重要的影像学依据。     

Volumetric evaluation of the ischemic lesion size with serial MRI in a transient MCAO model of the rat: comparison of DWI and T1WI

Magnetic resonance imaging (MRI) is applied in many studies on experimental cerebral ischemia in rodents to monitor the temporal evolution of ischemic damage. We report a protocol to evaluate the infarct size after middle cerebral artery occlusion with reperfusion (MCAO/R) in male Wistar rats. Imaging was performed with a 2.35 T scanner and we focused on diffusion-weighted imaging (DWI), T2-weighted imaging (T2WI) and postcontrast T1-weighted imaging (T1WI). We show the detailed procedure of volumetry, the contrast-to-noise ratio (CNR) and the intraindividual variability of infarct and hemispheric volumes at different reperfusion times. The presented method is of low variability if image contrast between ischemic and nonischemic tissue is very high, which is the case not only for all sequences at 8 and 12 h of reperfusion but also for DWI after 3 and 5 h of reperfusion. Furthermore, we describe the so-called mismatch region of lesion sizes depicted on DWI and postcontrast T1WI that suffers from cytotoxic edema but lacks contrast enhancement.     

Application of High-Resolution CUBE Sequence in Exploring Stroke Mechanisms of Atherosclerotic Stenosis of Middle Cerebral Artery

Background

This study aimed to analyze the vascular wall and atherosclerotic plaques of the middle cerebral artery (MCA) and compare their differences between patients with cerebral infarction and transient ischemic attack (TIA) using 3-dimensional fast-spin-echo T1-weighted sequence (namely CUBE).

流行性乙型脑炎的影像学特点

目的：分析流行性乙型脑炎的MRI表现特征，探讨MRI对流行性乙型脑炎诊断价值。方法：回顾分析经临床和血清学证实的4例流行性乙型脑炎不同发病时期的MRI资料，其中成人1例，儿童3例。MRI均采用常规横轴位T1WI和T2WI，冠状面FLAIR及DWI。成年患者还经钆喷酸葡胺（GD2DTPA）增强检查。结果：4例患者MRI都有双侧丘脑、中脑病变，其中2例还有大脑皮质病变。增强扫描病灶未见强化。结论：流行性乙型脑炎的MRI特征是双侧丘脑和中脑异常信号。     

高分辨磁共振成像评价他汀治疗逆转颈动脉粥样硬化斑块研究进展

动脉粥样硬化斑块破裂继发血栓形成可引起急性心脑血管事件,严重威胁人类健康。而 他汀治疗可延缓甚至逆转动脉粥样硬化斑块进展,但目前临床上缺少评价他汀治疗对斑块影响的 无创性影像检查技术。高分辨磁共振成像技术(high-resolution magnetic resonance imaging,HR-MRI)作 为一项新兴组织成像技术,具有良好的组织一致性,能够准确分析动脉粥样硬化斑块负荷,判定及 定量分析斑块内各组分（包括纤维帽、富含脂质核心、钙化及出血等）,通过选择超小超顺磁性氧化 铁作为对比剂还可以评价斑块内炎症水平。本文就HR-MRI评价他汀治疗逆转颈动脉粥样硬化斑块 进展做一简要综述。     

高分辨磁共振成像在基底动脉粥样硬化性疾病中的临床应用

高分辨磁共振成像可以清晰显示基底动脉的管壁和斑块结构,这对于探究基底动脉粥样硬化性重塑、斑块成分和斑块分布具有重要临床价值,有助于阐明基底动脉粥样硬化与缺血性卒中的关系。     

Middle cerebral artery plaque imaging using 3-Tesla high-resolution MRI

Diagnosis of deep subcortical infarcts based on atherosclerosis of the middle cerebral artery (MCA) is important because this type of infarct is usually more aggressive than typical lacunar infarcts. However, current imaging techniques are of limited utility in the diagnosis of MCA plaques. Here, we report the use of 3-Tesla (3T) high-resolution moderate T(2)-weighted imaging (HRT(2)WI) to detect MCA plaques in three patients with acute MCA perforator territory infarcts. MCA plaques were seen with HRT(2)WI in a patient with MCA stenosis, which was observed by magnetic resonance angiography (MRA). Of the two patients without MCA stenosis (also confirmed by MRA), one had thin MCA plaques and the other had normal walls based on HRT(2)WI. Progression of symptoms occurred in the patients with plaques. We conclude that 3T HRT(2)WI can identify plaque on MCA walls and has the potential to identify patients at risk for stroke progression or recurrence.