颈动脉斑块高分辨磁共振成像的临床研究

发布时间：2018-05-01 14:05

本文选题：颈动脉斑块 + 磁共振　；参考：《南方医科大学》2014年硕士论文

【摘要】：第一部分缺血性卒中患者颈动脉斑块的MRI表现特征 [研究目的] 通过3.0T MRI多对比序列研究缺血性卒中患者颈动脉斑块的影像学表现,分析斑块的成分及纤维帽情况,判断斑块稳定性,定量评价斑块负荷,比较易损斑块组与稳定斑块组的斑块成分特征、斑块负荷及临床危险因素是否存在差异。 [材料与方法] 1、研究对象搜集我院2012年至2013年间神经内科同时满足以下入选标准的患者共65例,入选标准：1)年龄在18周岁及以上的缺血性卒中和/或TIA患者；2)为近期发作的缺血性卒中或TIA患者(症状发生在≤14天之内)；3)超声提示颈动脉存在AS斑块或内膜中膜厚度(IMT)≥1.5mm所有患者检查均得到伦理委员会同意并签署知情同意书。 2、主要设备、扫描序列及参数使用Philips公司生产的Achieva3.0T磁共振扫描仪、颈动脉专用8通道相控阵表面线圈进行颈动脉MR多序列对比扫描。扫描序列和参数：颈动脉专用8通道相控阵表面线圈固定患者下颌及颈部,扫描时嘱患者保持静止并尽量减少吞咽动作。对患者的双侧颈动脉先行2D-TOF扫描,MIP法重建MRA图像以获得颈动脉分叉的准确位置,在颈动脉分叉层面上下2cm的范围内行横轴位3D TOF、T1WI、T2WI、MP-RAGE、3DMERGE扫描,各序列主要参数为：(1)3D TOF, TR/TE20ms/4.9ms, FOV140mm×140mm,层厚2mm；(2)T1WI,四反转恢复(QIR), TR/TE800ms/10ms, FOV140mm×140mm,层厚2mm；(3)T2M,多层双反转恢复(MDIR), TR/TE4800ms/50ms, FOV140mm×140mm,层厚2mm；(4)MP-RAGE,3D FFE, TR/TE10ms/4.8ms, FOV140mm×140mm,层厚2mm;(5)3D MERGE,3D FFE, TR/TE10ms/4.8ms, FOV250mm×160mmX70mm,层厚2mm。 3、颈动脉MRI图像质量分级评分按各序列颈动脉MRI图像质量从差到好分为1-4级分别评为1-4分,由两名有经验的放射科医师采用双盲法进行打分,整体图像质量≤2级则数据将不用于统计。 4、颈动脉斑块图像分析及处理由两位经过系统培训的人员利用美国华盛顿大学自主开发的图像分析软件CASCADE对颈动脉MR图像进行分析。分析人员对所有病例临床资料等信息采取盲法原则。颈动脉磁共振分析内容包括：1)颈动脉斑块成分识别：钙化(Calcification, CA)、富含脂质的坏死核(lipid-rich necrotic core, LRNC)、斑块内出血(plaque hemorrhage,IPH)及各成分体积、所占管壁百分比；2)颈动脉粥样硬化斑块形态学测量：血管总面积(total vessel area, TVA)、管腔面积(lumen area, LA)、管壁厚度(wall thickness, WT)、管壁面积(wall area,WA)和管壁标准化指数(normalized wall index, NWI);3)颈动脉斑块表面纤维帽状态判断：完整或者破裂。 5、统计学方法数据运用SPSS13.0统计软件包处理。计量资料以均数±标准差(x±s)表示。易损组与稳定组之间的颈动脉斑块负荷指标、临床危险因素的对比分析使用两独立样本t检验、Fisher's确切概率分析、Wilcoxon秩和检验等。统计学检验均使用双尾侧的检验方法,有统计学意义的检验水平为P0.05。定量数据的结果取两名评价者测得的平均值用于分析,定性数据不一致时协商达成一致意见用于分析。 [结果] 1、65例患者中,59例患者的图像符合研究要求(除外1例为颈动脉夹层患者,3例图像质量较差,2例因一侧颈动脉数据丢失),年龄约43-83岁,平均62.27±9.99岁,其中男性39例,女性20例。高血压患者44例,糖尿病患者21例,吸烟患者20例,总胆固醇(TC)4.86±1.23mmol/L,甘油三脂(TG)1.73±1.18/mmol/L,高密度脂蛋白胆固醇(HDL)1.25±0.29mmol/L,低密度脂蛋白胆固醇(LDL)3.09±1.12mmol/L。分析59例患者总体颈动脉斑块负荷和成分特征；按斑块稳定性分组：易损斑块组10例,稳定斑块组49例。 2、易损斑块组与稳定斑块组的斑块成分的比较：易损斑块组斑块内CA、LRNC、IPH的体积及相应的面积比均与稳定斑块组存在着明显差异(P0.05)。 3、易损斑块组与稳定斑块组的斑块负荷的比较：平均血管总面积(TVA)两者差异无统计学意义(P0.05),而平均管腔面积(LA)及最小管腔面积(minLA)易损斑块组均小于稳定斑块组,差异有统计学意义(P0.05)；平均管壁面积(WA)、平均管壁厚度(WT)、平均标准化管壁指数(NWI)及最大管壁面积(max WA)、最大管壁厚度(max WT)、最大标准化管壁指数(max NWI)易损斑块组均比稳定组大,差异均有统计学意义(P0.05)。 4、易损斑块患者与稳定斑块患者的临床危险因素的差异：除年龄外,两组其余各危险因素差异无统计学意义(P0.05)。 [结论] 1、将MRI“黑血”、“白血”技术相结合观察斑块,能更全面、更准确的观察管壁结构,分析斑块的成分及其体积。 2、易损斑块为斑块内出血及／或纤维帽破裂的斑块,其成分较稳定斑块复杂。 3、易损斑块与稳定斑块的血管负荷指标NWI、WA、WT间有显著性差异,故可用诸负荷指标评价斑块。 4、易损斑块组与稳定斑块组的临床危险因素无显著性差异。第二部分颈动脉斑块与缺血性卒中的相关性研究 [研究目的] 本实验旨在通过MRI定量分析,探讨卒中患者症状侧与无症状侧斑块的负荷及成分的差别,同时分析斑块负荷、斑块成分体积与同侧大脑急性梗塞灶体积间的相关性。 [材料与方法] 1、研究对象及分组研究对象与第一部分相同,65例患者中共61例患者颈动脉图像纳入实验(除外1例夹层,3例图像质量较差),但因其中2例患者右侧部位颈动脉数据丢失,剩余120侧颈动脉斑块图像符合研究要求。血管分为2组,症状侧颈动脉：同侧大脑半球颈内动脉系统供血区发生缺血性卒中的那侧动脉,共有89侧血管,其中33侧血管相应供血区发生了急性脑梗；无症状侧颈动脉：同侧大脑半球颈内动脉供血区未发生明显缺血性脑卒中的那侧动脉,共31侧。 2、仪器设备及参数仪器设备及颈动脉MRI扫描同第一部分,头部采用8通道标准头部接收线圈。主要成像序列为横轴位T1W、T2W、T2W FLAIR、DWI、3D TOF MRA。各序列主要参数为：(1) T1WI, TR/TE2000ms/20ms,层厚=6mm,间距=1mm, FOV=240mm×240mm, Matrix=256×256;(2) T2W, TR/TE3000ms/80ms,层厚=6mm,间距=1mm,FOV=240mm×240mm, Matrix=256×256;(3)T2WI FLAIR, TR/TE11000ms/125ms,层厚=6mm,间距=1mm, FOV=240mm×240mm, Matrix=256×256;(4) DWI, TR/TE1910ms/44.4ms,层厚=6mm,间距=1mm, FOV=240mm×240mm;(5)3D TOF MRA, TR/TE20ms/4.9ms。 3、颈动脉MRI图像质量分级按各序列颈动脉MRI图像质量从差到好分为1-4级分别评为1-4分,由两名放射科医师进行打分,整体图像质量≤2级则数据将不用于统计。 4、图像数据处理及测量由两名拥有5年以上MR诊断经验的放射科医生进行图像分析,分析人员对病例临床资料、颈动脉MR图像等信息采取盲法原则,脑MR图像分析内容包括：有、无T2W FLAIR高信号及其大小；有无DWI高信号及其大小。颈动脉斑块MR图像分析同第一部分。 5、统计学方法数据应SPSS13.0统计软件包处理。计量资料以均数±标准差(x±s)表示。卒中侧和非卒中侧两组间的颈动脉斑块负荷、成分差异采用两独立样本t检验、Fisher's确切概率检验及Wilcoxon秩和检验。颈动脉斑块负荷、斑块各成分体积与同侧大脑DWI高信号病灶体积间的关系采用Spearman相关分析。双侧检验以P0.05为差异有统计学意义。 [结果] 1、症状侧和无症状侧颈动脉斑块特征的差异 1.1卒中患者双侧颈动脉各项指标的差异无统计学意义(P0.05)； 1.2症状侧的颈动脉的管壁面积(WA)、管壁厚度(WT)、管壁标准化指数(NWI)均较无症状侧高,差异有统计学意义(P0.05),血管总面积(TVA)、管腔面积(LA)在症状侧和无症状侧中是没有统计学差异的(P0.05)； 1.3症状侧与无症状侧颈动脉斑块LRNC、IPH的发生率两者间存在显著性差异,而钙化、FCR发生率无统计学意义,而在预测临床症状方面,发现斑块内LRNC、纤维帽破裂的优势比分别为8.578,2.125,而IPH均发生于症状侧；钙化、LRNC、IPH体积在两者间存在显著性差异,以LRNC和IPH明显。 2、斑块负荷与同侧急性脑梗死(DWI高信号)体积的相关性,颈动脉斑块负荷中WT、NWI与同侧大脑半球急性脑梗死的体积间呈正相关关系,以Mean NWI为著,相关程度程度较强r=0.625,而Mean LA与同侧大脑半球急性脑梗死的体积呈负相关关系,但相关程度一般r=-0.461。 3、颈动脉斑块成分中钙化体积、LRNC体积、IPH体积均与同侧大脑半球急性脑梗死体积间呈正相关关系,相关程度一般,r值分别为0.533,0.436,0.461。 [结论] 1、症状侧与无症状侧的颈动脉斑块负荷是有差异的,但双侧病变总体呈对称性改变。 2、症状侧斑块成分较无症状侧复杂,LRNC, IPH与临床缺血事件的发生密切相关,FCR一定程度上也提示发生脑卒中的发生。 3、同侧颈动脉斑块负荷中WT、NWI值越大,即斑块负荷越重,相应同侧大脑半球颈内动脉供血区急性脑梗体积越大,而Mean LA值越小,即血管越狭窄,相应同侧大脑半球急性脑梗死的体积越大。 4、斑块成分越复杂,发生急性缺血事件的可能性越大。
[Abstract]:Part one MRI features of carotid plaques in patients with ischemic stroke
[research purposes]
The imaging findings of carotid artery plaque in ischemic stroke patients were studied by 3.0T MRI multi contrast sequence, the composition of plaque and the condition of fibrous cap were analyzed, plaque stability was judged, plaque load was evaluated, plaque composition characteristics of vulnerable plaque group and stable plaque group were compared, and there was difference between plaque load and clinical risk factors.
[materials and methods]
1, the object of research
A total of 65 patients who met the following criteria for neurology from 2012 to 2013, were selected as criteria: 1) ischemic stroke neutralization / or TIA patients aged 18 and above; 2) ischemic stroke in the near future or TIA patients (symptoms occurring within 14 days); 3) the carotid artery had AS plaque or intima. The thickness of the medial membrane (IMT) was greater than 1.5mm. All patients were approved by the ethics committee and signed informed consent.
2, main equipment, scanning sequence and parameters
The Achieva3.0T MR MRI scanner produced by Philips was used to perform the MR multiple sequence contrast scan of the carotid artery.
Scanning sequence and parameters: the 8 channel phased array surface coil of the carotid artery was used to fix the patient's mandible and neck. The patient kept static and minimized the swallowing. 2D-TOF scan on the bilateral carotid artery of the patient, the MIP method to reconstruct the MRA image to obtain the accurate position of the carotid bifurcation, and the 2cm model at the carotid bifurcation level. 3D TOF, T1WI, T2WI, MP-RAGE, 3DMERGE scan, the main parameters of each sequence are: (1) 3D TOF, TR/TE20ms/4.9ms, FOV140mm x 140mm, layer thick 2mm; (2) four inversion recovery (3); (3) MP-RAGE, 3D FFE, TR/TE10ms/4.8ms, FOV140mm x 140mm, layer thickness 2mm; (5) 3D MERGE, 3D FFE, TR/TE10ms/4.8ms, X *, layer thickness
3, MRI image quality grading of carotid artery
According to the quality of the MRI image of each sequence, the quality of the MRI image was divided into 1-4 points, and two experienced radiologists were scored by double blind method. The overall image quality was less than 2, and the data would not be used for statistics.
4, analysis and treatment of carotid artery plaque image
The MR image of the carotid artery was analyzed by two system trained personnel using the image analysis software CASCADE, which was developed by University of Washington. The analyst took the blind principle for all cases of clinical data. The contents of carotid magnetic resonance analysis included: 1) identification of carotid plaque composition: calcification (Calcification, CA) Lipid-rich necrotic core (LRNC) rich in lipid, hemorrhage (plaque hemorrhage, IPH) and the volume of each component, the percentage of the wall of the tube; 2) the morphological measurement of carotid atherosclerotic plaque: total vascular area (total vessel area, TVA), lumen area (lumen), tube wall thickness, tube wall Wall area (WA) and normalized wall index (NWI); 3) judging the status of fibrous caps on the surface of carotid plaques: complete or ruptured.
5, statistical method
The data were treated with SPSS13.0 statistical software package. The measurement data were expressed with mean standard deviation (x + s). The carotid plaque load index between the vulnerable group and the stable group, the comparative analysis of the clinical risk factors using two independent samples t test, the exact probability analysis of Fisher's, the Wilcoxon rank sum test, and so on. The statistical test used the examination of the double tail side. The test method, the statistical test level is the result of the P0.05. quantitative data, the average value measured by two evaluators is used for the analysis, and the consensus is reached when the qualitative data is inconsistent.
[results]
Of the 1,65 patients, 59 cases were in accordance with the research requirements (excluding 1 cases of carotid artery dissection, 3 cases of poor image quality and 2 cases of loss of carotid artery data), age 43-83 years old, with an average of 62.27 + 9.99 years, including 39 men, 20 women, 44 hypertensive patients, 21 cases of diabetes, 20 cases of smoking, total cholesterol (TC) 4.86 + 1.23mmol/L, glycerol three (TG) 1.73 + 1.18/mmol/L, high density lipoprotein cholesterol (HDL) 1.25 + 0.29mmol/L, low density lipoprotein cholesterol (LDL) 3.09 + 1.12mmol/L. analysis of 59 patients with overall carotid plaque load and composition characteristics, according to plaque stability group: vulnerable plaque group 10 cases, stable plaque group 49 cases.
2, comparison of plaque composition between vulnerable plaque group and stable plaque group: the volume and area ratio of CA, LRNC, IPH and corresponding area in vulnerable plaque group were significantly different from those in the stable plaque group (P0.05).
3, compared with the plaque load in the vulnerable plaque group and the stable plaque group, the average total area of vascular area (TVA) had no significant difference (P0.05), while the average lumen area (LA) and the smallest lumen area (minLA) vulnerable plaque group were less than the stable plaque group, and the difference had the significance (P0.05), the mean tube wall area (WA), and the mean tube wall thickness (WT). The average standardized tube wall index (NWI) and the maximum tube wall area (max WA), the maximum tube wall thickness (max WT), the maximum standardized tube wall index (max NWI) vulnerable plaque group were all larger than the stable group, the difference was statistically significant (P0.05).
4, there were differences in clinical risk factors between vulnerable plaque patients and stable plaque patients: except for age, there was no significant difference in the other risk factors between the two groups (P0.05).
[Conclusion]
1, combining MRI "black blood" and "white blood" technology to observe plaques, we can observe the wall structure more comprehensively and accurately, and analyze the composition and volume of plaques.
2, vulnerable plaque is plaque with hemorrhage and / or fibrous cap rupture, and its composition is more stable than that of plaque.
3, there is a significant difference between vulnerable plaque and stable plaque vascular load index NWI, WA, WT, so the load index can be used to evaluate plaque.
4, there was no significant difference in clinical risk factors between vulnerable plaque group and stable plaque group.
The second part is the correlation between carotid plaques and ischemic stroke.
[research purposes]
The purpose of this study was to investigate the difference in the load and composition of symptomatic and asymptomatic plaques in patients with stroke by MRI quantitative analysis, and to analyze the correlation between plaque load, plaque volume and the volume of acute cerebral infarction in the same side.
[materials and methods]
1, research objects and groups
The subjects were the same as the first part. The carotid artery images of 61 patients in 65 patients were included in the experiment (excluding 1 dissections and 3 cases of poor image quality). However, the carotid artery data in the right part of the 2 patients were lost and the remaining 120 carotid plaques were in accordance with the study requirements. The blood tube was divided into 2 groups, the symptomatic carotid artery: the ipsilateral cerebrum cervix. There were 89 vessels in the artery of the ischemic stroke in the blood supply area of the internal artery system, of which there were acute cerebral infarction in the corresponding blood supply area of 33 vessels, and the asymptomatic lateral carotid artery: there were 31 sides of the artery in the same lateral cerebral hemisphere of the internal carotid artery.
2, instrument and equipment and parameters
The 8 channel standard head receiving coils are used in the first part of the instrument and the MRI scan of the carotid artery. The main imaging sequences are horizontal axis T1W, T2W, T2W FLAIR, DWI, and 3D TOF MRA. sequence main parameters are: (1) T1WI, TR/TE2000ms/20ms, thick =6mm, spacing, 256; (2) =6mm, distance =1mm, FOV=240mm x 240mm, Matrix=256 x 256; (3) T2WI FLAIR, TR/TE11000ms/125ms, layer thickness =6mm, interval =1mm, FOV=240mm * 240mm, 256;
3, MRI image quality classification of carotid artery
According to the MRI image quality of the carotid artery of each sequence from poor to good score of 1-4, the scores were scored 1-4 points respectively. Two radiologists were awarded the score, and the overall image quality was less than 2. The data would not be used for statistics.
4, image data processing and measurement
An image analysis was performed by two radiologists with more than 5 years of MR diagnostic experience. The analyst took the blind principle of the case clinical data and the MR image of the carotid artery. The MR image analysis of the brain included: there was no high signal and size of T2W FLAIR; there was no DWI high signal and its size. The analysis of the MR image of the carotid plaque was the same as the first part. Points.
5, statistical method
The data should be processed by SPSS13.0 statistical software package. The measurement data were represented by mean number + standard deviation (x + s). The carotid plaque load between the two groups of stroke side and non stroke side was measured by two independent sample t test, the exact probability test of Fisher's and the Wilcoxon rank sum test. The carotid plaque load, the volume of plaque and the high DWI in the same side of the brain. The correlation of signal lesion volume was analyzed by Spearman correlation analysis. Bilateral test showed a statistically significant difference between P0.05.
[results]
1, differences in plaque characteristics between symptomatic side and asymptomatic lateral carotid artery.
1.1 there was no significant difference in the indexes of bilateral carotid artery in stroke patients (P0.05).
1.2 the wall area of the carotid artery (WA), the thickness of the tube wall (WT), the tube wall standardization index (NWI) were higher than that of the asymptomatic side (P0.05), the total vascular area (TVA), and the lumen area (LA) in the symptomatic side and asymptomatic side (P0.05).
1.3 there were significant differences in the incidence of LRNC and IPH in symptomatic side and asymptomatic carotid artery plaque, while calcification, and the incidence of FCR were not statistically significant. In predicting the clinical symptoms, LRNC was found in plaque, and the ratio of fibrous cap rupture was 8.578,2.125 respectively, and IPH occurred at the symptomatic side; calcification, LRNC, and IPH volume were stored between the two. In the significant difference, LRNC and IPH are obvious.
2, the correlation between plaque load and the volume of the ipsilateral acute cerebral infarction (DWI high signal), WT, NWI and the volume of acute cerebral infarction in the ipsilateral cerebral hemisphere were positively correlated with the volume of acute cerebral infarction in the same side of the cerebral hemisphere, and the degree of correlation was stronger r=0.625, while Mean LA and the volume of acute cerebral infarction in the same hemisphere were negatively correlated, but the phase of Mean LA was negatively correlated with the volume of acute cerebral infarction in the same hemisphere. General r=-0.461.
3, the volume of calcification, the volume of LRNC, and the volume of IPH in the carotid plaque components were positively correlated with the volume of acute cerebral infarction in the same hemisphere, and the correlation was general, and the R value was 0.533,0.436,0.461., respectively.
[Conclusion]
1, there were differences in carotid plaque burden between symptomatic side and asymptomatic side, but bilateral lesions showed symmetrical changes.
2, the plaque composition on the symptom side is more complicated than the asymptomatic side. LRNC and IPH are closely related to the occurrence of clinical ischemic events. FCR also indicates the occurrence of stroke to some extent.
3, the greater the value of WT and NWI in the ipsilateral carotid artery plaque load, the heavier the plaque load, the greater the volume of acute cerebral infarction in the internal carotid artery supply area of the same hemisphere, and the smaller the Mean LA value, the more narrower the blood vessels are, the larger the volume of the corresponding cerebral hemisphere acute cerebral infarction.
4, the more complex plaque components, the greater the possibility of acute ischemic events.

【学位授予单位】：南方医科大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R743.3;R445.2

【参考文献】