磁共振黑血iMSDE序列在颈动脉狭窄诊断中的初步临床应用体会

目的通过与数字减影血管造影(DSA)比较,评价MR黑血运动致敏驱动平衡改良技术(improved motionsensitized driven equilibrium,iMSDE)序列在诊断颈动脉狭窄中的临床价值。方法对32例患者的39支粥样硬化狭窄性颈动脉进行DSA及黑血iMSDE成像,比较两者在评估狭窄处最小管腔直径、狭窄处斑块累及长度、斑块破溃和判断最大狭窄部位的差异。结果黑血iMSDE成像与DSA相比:在判断颈动脉最大狭窄部位有较好的一致性(Kappa值=0.894);狭窄处最小管腔直径无显著性差异[(3.3±0.9)mm vs(3.2±0.8)mm,P=0.098];黑血iMSDE成像所示狭窄处斑块累及长度明显大于DSA[(21.9±5.6)mm vs(15.3±3.4)mm,P<0.001];黑血iMS-DE成像与DSA显示斑块破溃一致性较好。结论磁共振黑血iMSDE成像能清晰显示颅外段颈动脉管壁结构和粥样斑块的形态,并为临床提供较可靠和有价值的信息。     

颈动脉粥样硬化斑块动物模型的MRI评价

目的:利用新西兰兔建立颈动脉粥样硬化模型,探索颈动脉粥样硬化斑块模型建立的可行性,并通过MR特殊线圈检测斑块,与病理对照观察斑块的MRI表现,为进一步研究颈动脉粥样硬化斑块与脑缺血的关系奠定基础。材料和方法:利用高脂饮食饲养成年兔20只,饲养前均行颈动脉检查,作为正常对照。8周后,在DSA辅助下经球囊损伤一侧颈动脉内膜,造影观察到内壁毛糙后停止操作。7d后行MR扫描观察颈动脉管壁信号变化。继续高脂饲养2个月后,多次行颈动脉MR检查,最后取病理对照。结果:20只兔饲养至3周时由于各种原因死亡4只,行球囊拉损术时死亡4只,其余12只均造模成功,成功率为75%(12/16)。第一次MRI显示管壁T_1WI、PDWI及T_2WI均为高信号,第2-6次MRI检查显示管壁内膜明显增厚,病理显示管壁内膜下局部泡沫细胞明显增多,同时平滑肌细胞积聚,形成类似于人类病变的粥样斑块。结论:高脂饮食饲养后行颈动脉球囊拉损制作兔颈动脉粥样硬化斑块是切实可行的办法,MRI是良好的检测颈动脉损伤和显示颈动脉斑块的方法。     

颈动脉粥样斑块3T MR高分辨成像和MRA诊断

目的:应用3.0T MR高分辨管壁成像和MR血管造影在体显示颈动脉粥样斑块,探讨MR对颈动脉斑块的诊断价值。方法:经彩超检查证实的症状性颈动脉狭窄37例,所有病例行管腔MRA和管壁高分辨MR检查,MR检查序列包括3DTOF、DIR T1WI、T2WI、PDWI和MRA。其中,17例检查前1周内行CT血管造影检查,9例患者检查后1周内行颈动脉内膜剥脱术。根据颈动脉内膜剥脱术手术部位,将获得的病理标本与MR图像逐层对照,研究斑块脂质成分、纤维成分和纤维帽、斑块钙化、出血和脂质坏死池等MR表现,探讨斑块变性的MR表现及其病理基础。结果:37个病例共发现52条颈动脉分叉处斑块,其中,管腔轻度狭窄24条(46.1%),中度狭窄19条(36.5%),重度狭窄7条(13.5%),闭塞2条(3.9%)。斑块钙化21条(40.4%)、无钙化斑块31条(59.6%);31条软斑块中纤维成分为主斑块8条(15.6%),有明显脂质核心斑块23条(44.2%);其中,伴斑块出血5条(10%)、脂质坏死核心3条(6%),纤维帽撕裂(溃疡或纤维帽撕裂)3条(6%)。相对于胸锁乳突肌,脂质坏死池在TOF、T1WI、PDWI、T2WI均呈显著高信号,钙化在各序列均呈低信号。斑块内出血的信号与出血的时间有关,新鲜出血各序列表现为点、结节或片状高信号,亚急性出血或者陈旧出血的信号与出血时间长短有关。结论:颈动脉MRA和管壁高分辨成像是评估颈动脉斑块风险性的有效手段,无创性MRA可以显示颈动脉斑块的狭窄程度;管壁高分辨成像可以直接显示斑块纤维帽、斑块内结构和成分,预测斑块脱落的风险性。     

1.5T MRI评价颈动脉粥样硬化与脑梗死的相关性研究

目的:通过MRI检测探讨颈动脉粥样硬化与脑梗死之间的关系。方法:选取2014年10月-2015年12月我院收治的60例MRI证实的脑梗死患者和同期检查的60例体检正常的无脑梗死健康者(对照组),两组行MRI检查,扫描序列包括二维时间飞跃法(2D-TOF)成像、T1WI、T2WI及增强颈部血管成像,研究并分析斑块内成分及其分型。结果:60例急性脑梗死患者中有55例颈动脉颅外段检出粥样硬化斑块,与对照组比较(15/60)差异有统计学意义(P<0.05);两组人群颈动脉粥样硬化斑块的分布情况比较差异无统计学意义(P>0.05);两组人群颈动脉粥样硬化斑块不稳定斑块发生率比较有统计学意义(P<0.05)。结论:颈动脉粥样硬化与脑梗死之间有密切的相关性,对中老年人常规进行1.5T MRI颈动脉粥样斑块成分预测,可作为脑梗死发生的预测因素,对积极防治颈动脉粥样硬化斑块导致的脑梗死发生具有非常重要的意义。     

颈动脉粥样硬化的高分辨力MRI研究

目的:评价高分辨力MRI在显示和评价颈动脉粥样硬化斑块方面的价值。方法:采用3in表面线圈,DIRT1WI、FSET2WI和3DTOF序列对19例患者及3例志愿者进行颈动脉高分辨力MRI成像,评价有无硬化斑块并对其初步分型。结果:MRI清晰显示15例31处颈动脉粥样硬化改变,包括颈总动脉4处,颈动脉分叉17处,颈内动脉9处及颈外动脉1处。硬化斑块在DIRT1WI、FSET2WI表现为管壁不规则增厚,根据其信号改变参照AHA分类分为Ⅲ型12个、Ⅳ～Ⅴ型11个,Ⅵ型2个,Ⅶ型6个。在显示血管壁改变方面DIRT1WI优于其它序列。结论:高分辨力MRI能清晰显示颈动脉粥样硬化改变,根据其信号改变能判断其组成成分及其性质,为临床选择治疗方案及预后提供帮助。     

高分辨力MRI对颈动脉粥样硬化斑块稳定性评估的价值

目的 :探讨高分辨力MRI对动脉粥样硬化斑块稳定性评估的价值。方法 :选择28例经颈动脉超声诊断为颈动脉粥样硬化斑块的患者行斑块高分辨力MRI检查,观察颈动脉粥样硬化斑块的成分。结果:28例17个不稳定性斑块和15个稳定性斑块中,高分辨力MRI显示钙化、脂质核心、纤维帽、斑块内出血及纤维斑块差异均有统计学意义(均P0.05)。结论:高分辨力MRI对斑块成分及稳定性判定有重要价值。     

MR测定颈动脉易损斑块特征与急性缺血性脑卒中的关系

目的 分析急性缺血性脑卒中患者症状侧颈动脉粥样硬化病变特征与扩散加权成像(DWI)证实的急性脑梗死(ACI)发生及严重程度的关联性.方法 入组发生单侧肢体症状(颈内动脉供血区)的ACI患者103例,均在发病后1周内行颈动脉磁共振黑血成像(MR-BBI)及头颅常规MRI,测得症状侧颈动脉粥样硬化病变参数(管腔狭窄率、斑块负荷和成分)和相应供血区ACI病灶分布及大小,借此分析症状侧颈动脉斑块特征与ACI发生、大小的关联程度.结果 研究发现,症状侧颈动脉管壁体积标准化指数(PWV)及富脂质核(LRNC)含量是同侧供血区ACI病灶发生及大小的独立危险因素(校正管腔狭窄和临床因素前后,P<0.05).结论 ACI发生及大小与同侧供血颈动脉的斑块易损特征(高斑块负荷和大LRNC)相关联.MR-BBI能细致化评估斑块易损特征,有利于临床分层急性缺血性脑卒中的风险性及严重程度.     

破裂与非破裂颈动脉粥样硬化斑块周围血流动力学的MRI分析

目的 分析颈内动脉起始部粥样硬化斑块周围血流动力学改变,探讨可能导致纤维帽破裂的流体力学因素.方法 前瞻性纳入19例颈内动脉起始部粥样硬化病变患者,进行颈动脉MRI.观察斑块形态结构,并据此将斑块分为纤维帽完整组和纤维帽破裂组.利用颈动脉MR增强血管成像原始图像进行血流动力学分析,计算颈动脉分叉部血管管壁切应力(WSS)、静态压、血管狭窄率等数据,两组之间比较采用两独立样本的Mann-Whitney U检验和t检验.结果 19例颈内动脉起始部斑块中,纤维帽完整组8例、斑块纤维帽破裂11例.纤维帽完整组最大管壁切应力、平均管壁切应力、最小静态压及平均静态压对应的中位数(上下四分位数范围)分别为42.92(27.13～68.19)、32.04(21.21～55.68)、-1 717.36(-3 433.61～-721.10)、-1 341.64(-2 868.00～-612.86)Pa,纤维帽破裂组对应的数据分别为67.18(60.46～139.51)、55.76(40.41～124.57)、-3884.02(-18767.39～-2886.33)、-3065.92(-16064.18～-1 915.09)Pa,两组间差异有统计学意义(U值分别为18.00、18.00、17.00、18.00,P值均＜0.05).斑块纤维帽完整组和纤维帽破裂组颈内动脉狭窄率分别为(47.13±13.50)％、(62.91±11.96)％,两组之间比较差异有统计学意义(t=2.69,P=0.02).结论 破裂与非破裂颈动脉粥样硬化斑块间的血流动力学存在差异,可能会对斑块破裂造成影响.     

磁共振测定颈动脉粥样硬化特征与急性脑梗死的关系

目的:应用3.0T磁共振测定颈动脉斑块负荷、成分与急性脑梗死的发生及梗塞体积的相关性。方法:对62例急性颈内动脉供血区脑梗死患者行颈动脉血管壁磁共振检查,测量颈动脉管腔狭窄率和斑块负荷(最大管壁厚度及管壁体积标准化指数),评价斑块成分(坏死脂核,出血,钙化及纤维帽破裂),测得DWI急性脑梗死体积,计算OR值和Spearman秩相关系数。结果:症状侧颈动脉狭窄程度、最大管壁厚度、管壁体积标准化指数和斑块内出血、钙化和纤维帽破裂的发生率均高于非症状侧(P值均<0.05);症状侧颈动脉管壁体积标准化指数与同侧颈内动脉供血区急性脑梗死体积有较强的正相关(Spearman秩相关系数0.327,P<0.05)。斑块内出血和钙化是较强的急性脑梗死暴露因素(OR值分别为2.4和2.1,P值均<0.05)。结论:症状侧与非症状侧颈动脉斑块特征存在差异,且与急性脑梗死存在相关,提示这些特征可能为斑块不稳定重要因素。     

磁共振测定颈动脉斑块负荷与脑梗死缺血灶体积的关系

目的 应用3.0T磁共振测量急性脑缺血患者头颅缺血灶体积和颈动脉斑块负荷,探究两者之间的关系.方法 94例急性脑缺血患者在发病1周内行头颅和颈动脉磁共振多序列检查(头颅T1WI、T2WI、T2 FLAIR、DWI;颈动脉亮血3DTOF,黑血T1WI、T2WI及MPRAGE),测得脑内缺血灶的体积和颈动脉的管腔面积(LA)、血管总面积(TVA),并计算出管壁面积(WA)和管壁标准化指数(NWI).结果 (1)94例病例中,90例的图像符合研究要求;(2)两侧颈内动脉供血区缺血灶体积间差异均无统计学意义(P＞0.05);(3)两侧颈动脉的平均血管总面积(TVA)、管腔面积(LA)、管壁面积(WA)和管壁标准化指数(NWI)间的差异无统计学意义(P＞0.05);(4)缺血侧颈动脉的管壁标准化指数(NWI)较非缺血侧大,差异有统计学意义(P＜0.05) ;(5)颈动脉斑块负荷与同侧大脑缺血灶体积间存在明显的正相关(P＜0.01).结论 颈动脉粥样硬化与脑梗死的发生密切相关,3.0T磁共振黑血技术能定量测量颈动脉斑块负荷,从而对预测脑缺血事件的发生以及监测病情的进展、评价预后提供帮助.     

Association of carotid atherosclerotic plaque features with acute ischemic stroke: A magnetic resonance imaging study

Background and purpose

It remains unclear whether direct vessel wall imaging can identify carotid high-risk lesions in symptomatic subjects and whether carotid plaque characteristics are more effective indicators for cerebral infarct severity than stenosis. This study sought to determine the associations of carotid plaque characteristics by MR imaging with stenosis and acute cerebral infarct (ACI) sizes on diffusion weighted imaging (DWI).

Materials and methods

One hundred and fourteen symptomatic patients underwent carotid and brain MRI. ACI volume was determined from symptomatic internal carotid artery territory on DWI images. Ipsilateral carotid plaque morphological and compositional characteristics, and stenosis were also determined. The relationships between carotid plaque characteristics, stenosis and ACIs size were then evaluated.

Results

In carotid arteries with 30–49% stenosis, 86.7% and 26.7% were found to have lipid-rich necrotic core (LRNC) and intraplaque hemorrhage, respectively. Furthermore, 45.8% of carotid arteries with 0–29% stenosis developed LRNCs. Carotid morphological measurements, such as % wall volume, and the LRNC size were significantly associated with ipsilateral ACIs volume before and after adjustment for significant demographic factors (age and LDL) or stenosis in patients with carotid plaque (all p < 0.05).

Conclusions

A substantial number of high-risk plaques characterized by vessel wall imaging exist in carotid arteries with lower grade stenosis. In addition, carotid plaque characteristics, particularly the % wall volume and LRNC size, are independently associated with cerebral infarction as measured by DWI lesions. Our findings indicate that characterizing atherosclerotic plaque by MR vessel wall imaging might be useful for stratification of plaque risk and infarction severity.     

Multislice dark-blood carotid artery wall imaging: a 1.5 T and 3.0 T comparison

PURPOSE: To compare two multislice turbo spin-echo (TSE) carotid artery wall imaging techniques at 1.5 T and 3.0 T, and to investigate the feasibility of higher spatial resolution carotid artery wall imaging at 3.0 T. MATERIALS AND METHODS: Multislice proton density-weighted (PDW), T2-weighted (T2W), and T1-weighted (T1W) inflow/outflow saturation band (IOSB) and rapid extended coverage double inversion-recovery (REX-DIR) TSE carotid artery wall imaging was performed on six healthy volunteers at 1.5 T and 3.0 T using time-, coverage-, and spatial resolution-matched (0.47 x 0.47 x 3 mm3) imaging protocols. To investigate whether improved signal-to-noise ratio (SNR) at 3.0 T could allow for improved spatial resolution, higher spatial resolution imaging (0.31 x 0.31 x 3 mm3) was performed at 3.0 T. Carotid artery wall SNR, carotid lumen SNR, and wall-lumen contrast-to-noise ratio (CNR) were measured. RESULTS: Signal gain at 3.0 T relative to 1.5 T was observed for carotid artery wall SNR (223%) and wall-lumen CNR (255%) in all acquisitions (P < 0.025). IOSB and REX-DIR images were found to have different levels of SNR and CNR (P < 0.05) with IOSB values observed to be larger. Normalized to a common imaging time, the higher spatial resolution imaging at 3.0 T and the lower spatial resolution imaging at 1.5 T provided similar levels of wall-lumen CNR (P = NS). CONCLUSION: Multislice carotid wall imaging at 3.0 T with IOSB and REX-DIR benefits from improved SNR and CNR relative to 1.5 T, and allows for higher spatial resolution carotid artery wall imaging.     

Comparison between 2D and 3D high-resolution black-blood techniques for carotid artery wall imaging in clinically significant atherosclerosis

PURPOSE: To compare two- (2D) and three-dimensional (3D) black-blood imaging methods for morphological measurements of the carotid artery wall and atherosclerotic plaque. MATERIALS AND METHODS: A total of 18 subjects with 50% to 79% carotid stenosis were scanned with 2D (2-mm slice thickness) and 3D (1-mm/0.5-mm actual/interpolated slice thickness) T1-weighted fast spin-echo (FSE) black-blood imaging sequences with double inversion-recovery (DIR) blood suppression. Morphological measurements (lumen area, wall area, vessel area, mean wall thickness, and maximal wall thickness), signal-to-noise ratio (SNR) in the wall and lumen, and wall-lumen contrast-to-noise ratio (CNR) were compared between 2D and 3D images. The effect of improved slice resolution in 3D imaging was evaluated for visualization of small plaque components. RESULTS: Lumen SNR (P = 0.16), wall SNR (P = 0.65), and CNR (P = 0.94) were comparable between 2D/3D. There was no difference in average lumen area (P = 0.16), average wall area (P = 0.99), average vessel area (P = 0.0.58), mean wall thickness (P = 0.09), and maximum wall thickness (P = 0.06) between 2D/3D. Distributions of small plaque components such as calcification were better characterized by the 3D acquisition. There was a higher sensitivity to motion artifacts with 3D imaging, resulting in three examinations with low image quality. CONCLUSION: 2D and 3D protocols provided comparable morphometric measurements of the carotid artery. The major advantage of 3D imaging is improved small plaque component visualization, while the 2D technique provides higher reliability for image quality.     

Reconstruction of carotid bifurcation hemodynamics and wall thickness using computational fluid dynamics and MRI.

A thorough understanding of the relationship between local hemodynamics and plaque progression has been hindered by an inability to prospectively monitor these factors in vivo in humans. In this study a novel approach for noninvasively reconstructing artery wall thickness and local hemodynamics at the human carotid bifurcation is presented. Three-dimensional (3D) models of the lumen and wall boundaries, from which wall thickness can be measured, were reconstructed from black-blood magnetic resonance imaging (MRI). Along with time-varying inlet/outlet flow rates measured via phase contrast (PC) MRI, the lumen boundary was used as input for computational fluid dynamic (CFD) simulation of the subject-specific flow patterns and wall shear stresses (WSSs). Results from a 59-year-old subject with early, asymptomatic carotid artery disease show good agreement between simulated and measured velocities, and demonstrate a correspondence between wall thickening and low and oscillating shear at the carotid bulb. High shear at the distal internal carotid artery (ICA) was also colocalized with higher WSS; however, a quantitative general relationship between WSS and wall thickness was not found. Similar results were obtained from a 23-year-old normal subject. These findings represent the first direct comparison of hemodynamic variables and wall thickness at the carotid bifurcation of human subjects. The noninvasive nature of this image-based modeling approach makes it ideal for carrying out future prospective studies of hemodynamics and plaque development or progression in otherwise healthy subjects.     

Measurement of carotid wall volume and maximum area with contrast-enhanced 3D MR imaging: initial observations

PURPOSE: To investigate whether postcontrast three-dimensional (3D) magnetic resonance (MR) imaging would yield more accurate measurement of carotid artery wall volume and maximum wall area, which are both measures of plaque burden, than precontrast 3D MR imaging. MATERIALS AND METHODS: Eleven consecutive patients scheduled to undergo carotid endarterectomy were recruited for the study. A 3D fast gradient-recalled-echo sequence was applied to acquire both precontrast and postcontrast images of the carotid artery wall. The same sequence was used to image the ex vivo excised plaque as a reference for measurement of carotid wall volume and maximum wall area. RESULTS: The mean difference in maximum wall area between the precontrast in vivo measurements and the ex vivo measurements (mean +/- SD, 18.22 mm2 +/- 15.61) was significantly larger than that between the postcontrast in vivo measurements and the ex vivo measurements (12.33 mm2 +/- 14.49) (P =.02). The difference in wall volume between the precontrast in vivo measurements and the ex vivo measurements (41.81 mm3 +/- 36.51) was larger than that between the postcontrast in vivo measurements and the ex vivo measurements (32.73 mm3 +/- 35.00) (P =.004). Postcontrast images yielded better correlation with ex vivo images than did precontrast images, in both carotid luminal area (R = 0.88 for postcontrast images, R = 0.80 for precontrast images) and outer wall boundary area (R = 0.79 for postcontrast images, R = 0.71 for precontrast images) measurements. CONCLUSION: Postcontrast 3D MR imaging may be useful in the measurement of carotid artery plaque burden.     

Characterization of atherosclerotic plaque of carotid arteries with histopathological correlation: vascular wall MR imaging vs. color Doppler ultrasonography (US)

PURPOSE: To investigate whether the vessel wall MRI of carotid arteries would differentiate at-risk soft plaque from solid fibrous plaque by identifying liquid components more accurately than color Doppler ultrasonography (US). MATERIALS AND METHODS: This study included 54 carotid arteries in 54 consecutive patients who underwent carotid endarterectomy. MRI was performed using black-blood fat-suppressed (FS) T1-and FS T2-weighted TSE sequences. A total of 68 major segments of the 54 carotid plaques were grouped into four MR categories based on signal intensity index (SII). MR criteria used for the diagnosis of plaque vulnerability were: at-risk soft plaque including a segment of liquid component (category A or B), solid fibrous plaque (category C or D). The MR and US findings were compared with histopathological findings of endarterectomy specimens. RESULTS: Intraoperative findings and microscopic examination of endarterectomy specimens revealed 24 at-risk soft plaques and 30 solid fibrous plaques. The sensitivity, specificity, and accuracy for diagnosing at-risk soft plaque are 96%, 93%, and 94% for MR, and 75%, 63%, and 69% for color Doppler US, respectively. The slice-by-slice MR evaluation of carotid wall also revealed detailed information of plaque segments and correlated well with the features of corresponding histologic sections. CONCLUSION: Vessel wall MRI with MRI category could have a potential to more accurately diagnose an at-risk soft plaque predominantly composed of liquid components in comparison with color Doppler US.     

Parallel and nonparallel simultaneous multislice black-blood double inversion recovery techniques for vessel wall imaging

PURPOSE: To reduce long examination times of black-blood vessel wall imaging by acquiring multiple slices simultaneously and by using parallel acquisition techniques. MATERIALS AND METHODS: DIR-rapid acquisition with relaxation enhancement (RARE) techniques imaging up to 10 simultaneous slices per acquisition with single and multiple 180 degrees -reinversion pulses were developed. A slab-selective reinversion multislice DIR-RARE sequence incorporating generalized autocalibrating partially parallel acquisitions (GRAPPA) imaging was implemented. Four-channel and eight-channel carotid coils were built to test these sequences. A total of 11 subjects were studied. Contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) efficiency factor (SEF, SNR/unit time/slice) were measured from aortic images of three healthy subjects to determine optimal MR parameters. The DIR-RARE-GRAPPA sequence was run on aortas and carotid arteries of the five remaining healthy subjects and three atherosclerotic patients with optimal parameters (acquisition times 12-21 seconds). RESULTS: SEFs of slab-selective protocols were significantly higher than those of slice-selective protocols, and SEFs of DIR-RARE-GRAPPA protocols were significantly higher than corresponding non-GRAPPA protocols (P < 0.05). CNR was not significantly different for all imaging protocols. The DIR-RARE-GRAPPA multislice sequence showed 8.35-fold time improvement vs. single-slice DIR-2RARE sequence. CONCLUSION: Future MRI atherosclerotic plaque studies can be performed in substantially shorter times using these methods.     

应用高分辨MRI评估颈动脉斑块与体质指数的相关性

目的通过高分辨MRI,探讨患者颈动脉粥样硬化斑块与体质指数的相关性。方法选择行颈动脉磁共振检查的患者64例,将体质指数BMI<24.0kg/m 2患者分为非肥胖组(31例),BMI≥24.0kg/m 2分为肥胖组(33例),比较两组患者颈动脉斑块成分及负荷的差异。结果肥胖组缺血性脑卒中〔21(63.60)vs 11(35.50),P=0.024〕及高血脂〔16(48.50)vs 7(22.60),P=0.031〕患者较非肥胖组多。肥胖组斑块内钙化体积〔(13.32±21.08)mm 3 vs(3.00±11.0)mm 3,P=0.017〕及脂质核体积〔(75.45±123.62)mm 3 vs(18.80±62.75)mm 3,P=0.026〕明显大于非肥胖组。肥胖组与非肥胖组的易损斑块(P=0.021)、斑块最大管壁厚度(P=0.025)、管壁标准化指数(P=0.010)比较,差异有统计学意义。结论高分辨MRI可评估不同体质指数患者颈动脉斑块的稳定性,为肥胖患者病情预测及临床干预提供可靠参考依据。     

颈动脉增强对评价颈动脉斑块稳定性的作用

目的:通过分析颈动脉粥样硬化(AS)血管壁的强化特征,评价血管壁强化程度与斑块稳定性之间的关系.方法:148例临床疑为颈部血管狭窄的患者中61例行CTA、87例行CE-MRA检查,分析斑块的类型并测量邻近血管壁的强化程度以及管腔狭窄程度,评价管壁强化特征与斑块稳定性之间的关系.CTA组部分患者与DSA对照.结果:CTA组:狭窄血管74支,轻度狭窄34支,中度狭窄24支,重度狭窄19支,3支完全闭塞;软斑块32块,硬斑块25块,溃疡斑6块,软斑块处血管壁强化明显高于硬斑块,部分患者与DSA比较,二种检查方法对血管狭窄的显示无显著性差异.CE-MRA组:狭窄血管79支,轻度狭窄28支,中度狭窄33支,重度狭窄13支,5支完全闭塞;软斑块28块,硬斑块49块,血栓2块,软斑块处血管壁强化明显高于硬斑块.结论:CTA和CE-MRA在评价颈动脉粥样硬化斑块的稳定性方面各有优势,能够为临床预测缺血性脑卒中提供非常可靠准确的信息.