血流剪切应力和剪切率与动脉粥样硬化斑块形成的关系

目的：应用超声多普勒探讨剪切应力和剪切率与动脉粥样硬化斑块形成的关系。方法：对180例患者，572个动脉粥样硬化斑块的分布情况进行统计分析，观测血流剪切率与剪切应力。结果：572个动脉粥样硬化斑块发生在颈动脉窦部及分叉处267个（46．68％），颈总动脉起始部188个（32．86％），颈总动脉中段26个（4．55％），肠系膜上动脉起始处15个（2．62％），肾动脉起始处9个（1．57％），髂总动脉起始部47个（8．2％），髂总动脉分叉处13个（2．27％），股动脉7个（1．22％），升主动脉没有斑块形成。斑块多发生在动脉分叉（起始）处、分叉周围及动脉增宽区。结论：血流剪切应力增高和剪切应力与剪切率减低是导致动脉粥样硬化斑块形成的重要因素。     

闭塞性动脉硬化症髂股动脉形态学表现与中医证型的相关性研究

目的:探讨闭塞性动脉硬化症(arteriosclerosis obliterans,ASO)髂股动脉各分支截面积与中医辨证分型的相关性。方法:收集ASO住院患者79例,其中血瘀型54例,湿热下注型25例,并选取非ASO患者30例作为对照,分别行MSCT髂股动脉造影检查,对每组的腹主动脉远端分叉、髂总动脉分叉及股总动脉分叉横截面积进行测量、计算,并统计比较。结果:髂股动脉多数分支的内面积和相对狭窄度ASO组明显小于对照组,右股总动脉内面积血瘀型小于湿热下注型,左股深动脉相对狭窄度湿热下注型明显小于血瘀型;腹主动脉远端分叉内面积扩张率ASO组明显小于对照组,右髂总动脉内面积扩张率湿热下注型小于血瘀型,双侧股总动脉内面积扩张率湿热下注型大于血瘀型及对照组。结论:ASO患者髂股动脉截面积与非ASO患者差异具有统计学意义,而ASO患者各中医证型之间亦存在一定差别。     

Study of ilio-femoral artery anatomy using multi-slice spiral CT angiography

目的:探讨多层螺旋CT血管成像(MSCTA)对髂-股动脉解剖学研究的价值及临床意义.方法:搜集符合要求的病例350例,所有病例行16层螺旋CT增强扫描,采用容积再现技术对髂-股动脉进行三维重建.测量动脉分叉到髂嵴连线、股骨头上缘连线的垂直距离及动脉分叉夹角.结果:腹主动脉分叉到髂嵴连线的垂直距离为(5.71±13.64) mm.腹主动脉分叉、左右髂总动脉分叉、左右股总动脉分叉到股骨头上缘连线的垂直距离男性组分别为(121.20±12.87)、(85.38±13.48)、(82.59±14.48)、(42.56±10.91)、(41.38±10.71) mm,女性组分别为(127.35±13.78)、(92.43±13.59)、(89.11±13.10)、(36.27±10.82)、(36.45±11.25) mm.腹主动脉分叉夹角、左右髂总动脉分叉夹角男性组分别为(41.63±14.29)°、(25.83±12.31)°、(25.70±12.38)°,女性组分别为(43.40±11.37)°、(24.89±11.15)°、(21.80±10.98)°.结论:MSCTA能清晰显示髂-股动脉及其与髂嵴、股骨头的位置关系,是髂-股动脉影像解剖学研究和介入治疗前评价的有效方法.     

髂-股动脉MSCT血管成像解剖学研究

目的:探讨多层螺旋CT血管成像(MSCTA)对髂-股动脉解剖学研究的价值及临床意义。方法:搜集符合要求的病例350例,所有病例行16层螺旋CT增强扫描,采用容积再现技术对髂-股动脉进行三维重建。测量动脉分叉到髂嵴连线、股骨头上缘连线的垂直距离及动脉分叉夹角。结果:腹主动脉分叉到髂嵴连线的垂直距离为(5.71±13.64)mm。腹主动脉分叉、左右髂总动脉分叉、左右股总动脉分叉到股骨头上缘连线的垂直距离男性组分别为(121.20±12.87)、(85.38±13.48)、(82.59±14.48)、(42.56±10.91)、(41.38±10.71)mm,女性组分别为(127.35±13.78)、(92.43±13.59)、(89.11±13.10)、(36.27±10.82)、(36.45±11.25)mm。腹主动脉分叉夹角、左右髂总动脉分叉夹角男性组分别为(41.63±14.29)°、(25.83±12.31)°、(25.70±12.38)°,女性组分别为(43.40±11.37)°、(24.89±11.15)°、(21.80±10.98)°。结论:MSCTA能清晰显示髂-股动脉及其与髂嵴、股骨头的位置关系,是髂-股动脉影像解剖学研究和介入治疗前评价的有效方法。     

MSCT主动脉血流动力学分析及MSCTA的临床应用价值探讨

目的：探讨多层螺旋CT主动脉的血流动力学及MSCTA的临床应用价值。方法：采用多层螺旋CT对20例主动脉进行全程血管造影，测量主动脉5处CT值，即主动脉根部、主动脉弓部、平膈顶处、肾动脉起始处、髂总动脉分叉处。并对全程主动脉造影的MSCTA进行多平面重建(multi-planar reconstruction，MPR)、最大密度投影法(maximum intensity projection，MIP)、仿真内窥镜(virtual endoscopy，VE)、容积重建(volume rendering，VR)、表面阴影显示法(surface shadow display，SSD)重建。结果：20例主动脉全程MSCTA进行多种处理后显示主动脉夹层6例、腹主动脉瘤8例、主动脉粥样硬化症1例、右侧髂总动脉瘤1例及正常主动脉4例。主动脉各测量点平均CT值分别为主动脉根部208．05HU、主动脉弓部233．45HU、平膈顶处236．65HU、肾动脉起始处237．65HU、髂总动脉分叉处222．6HU。结论：利用MSCT可以对主动脉的血流动力学进行评价。主动脉全程的MSCTA有很大的临床应用价值。     

高血压病人颈动脉及股动脉改变的超声研究

目的超声观察高血压组和对照组的颈动脉及股动脉的结构和血流动力学信息。方法研究对象分为高血压组和正常对照组各80例,二维观察颈总动脉(CCA))及股总动脉(CFA)内径,内中膜厚度及有无斑块形成,利用彩色多普勒超声测量其收缩期血流峰值速度(PSV)、阻力指数(RI)并对照。结果高血压组较对照组颈动脉及股动脉内径和内膜厚度增加(P<0.05);高血压组的斑块发生率明显高于正常对照组(P<0.01);高血压组的PSV、RI较对照组无显著差异(P>0.05);高血压组中有斑块和无斑块的PSV、RI无显著差异(P>0.05)。结论超声检查无创、方便、可重复,不仅能够准确评价颈动脉及股动脉的血管壁结构,而且可检测血流动力学信息,从而成为临床高血压病防治中效果监测的可靠手段。     

MR评估在体血管壁切应力的方法探讨

目的 研究一种临床适用的MR技术在体无创性评估颈总动脉血管壁切应力(WSS)的方法.方法 选取1名健康志愿者,对其右侧颈总动脉行相位对比法MR血流定量扫描,应用三维抛物面(3DP)模型函数拟合方法,结合图像后处理技术,计算局部WSS,获取颈总动脉的血管横截面积、平均血流速度、最大速度及瞬时血流率等血流动力学参数,综合评估颈总动脉的血流动力学状态.结果 颈总动脉局部WSS值范围为(0.75±0.41)N/m2;平均血流速度为(23.4±12.0)cm/s,血管横截面积为(32.2±2.9)mm2;血流率为(7.8±4.6)ml/s.结论 MR血流定量技术结合3DP模型方法可以对颈动脉局部WSS大小、分布和变化进行评估.     

老年原发性高血压患者动态脉压与颈动脉粥样硬化相关性研究

目的:探讨老年原发性高血压患者动态脉压与颈动脉粥样硬化间的关系。方法:根据动态全天平均脉压将100例老年原发性高血压患者分为两组。所有患者均经超声检测颈总动脉、颈内动脉和颈外动脉分叉处的内膜中层厚度、血管内径,并计算斑块发生率。以颈总动脉最大内膜中层厚度(IMT max)作为评价颈动脉粥样硬化程度的指标。结果:脉压差大于60mmHg的患者颈总动脉内径、颈总动脉最大内膜中层厚度、颈动脉斑块发生率明显高于脉压差为40~60mmHg患者(P<0.05)。Pearson相关分析显示,平均脉压、平均收缩压及病程与颈总动脉最大内膜中层厚度呈明显正相关(r分别为0.410、0.217、0.247,P<0.05),而平均舒张压与颈总动脉最大内膜中层厚度呈负相关(r=-0.404,P<0.01)。结论:老年原发性高血压患者脉压差与颈动脉粥样硬化斑块和内中膜厚度相关,脉压差可能参与动脉粥样硬化的形成和发展。     

腹盆腔血管数字化三维模型指导血管内介入插管方式选择研究

目的利用腹盆腔血管及腰骶椎数字化三维模型,探讨左右髂总动脉分叉角度及分叉开口位置与髂总动脉长度的关系,从而指导血管内介入插管方式的选择。方法选取2011年9月至2013年5月在我科接受腹盆腔CTA检查患者439例,采用数字化三维重建技术构建患者腹盆腔血管及腰骶椎数字化三维模型,Mimics软件联合Geomagic软件对左右髂总动脉间分叉角度和左右髂总动脉长度进行测量,观察并记录左右髂总动脉分叉角度所对应椎体。通过统计学软件对左右髂总动脉分叉角度与其对应椎体位置及左右髂总动脉长度进行相关性分析。结果成功构建439例患者腹盆腔血管和腰骶椎三维模型,均清楚显示左右髂总动脉分叉角度及分叉开口位置。439例患者中左右髂总动脉分叉角度为平均(49.1±12.4)°,分叉开口位于L3~4有38例,L4上1/3有63例,L4中1/3有89例,L4下1/3有135例,L4~5有114例。左右髂总动脉平均长度分别为(45.6±15.6)mm和(43.3±15.4)mm。Pearson相关分析显示,左右髂总动脉分叉角度与其分叉开口位置高度存在负相关关系(r=-0.172,P<0.05),该分叉角度与左右髂总动脉长度也存在负相关关系(左侧:r=-0.171,P<0.05;右侧:r=-0.164,P<0.05)。结论左右髂总动脉分叉开口位置越低,其角度越大,相应髂总动脉长度越短,经股动脉行对侧髂内动脉直接插管距离短、易操作,成功率高;反之,插管路径就延长,直接插管难度增加,需用成襻插管技术,或进一步结合髂内外动脉分叉角度,评估是选择对侧还是同侧髂内动脉插管。     

髂-股动脉多层螺旋CT测量

目的:采用16层螺旋CTA对髂-股动脉进行测量,为经髂-股动脉介入诊疗提供影像学数据。方法:收集2010年6月～9月符合要求的连续病例350例,按照年龄21～40岁、41～60岁、61～89岁分为A、B、C组。经肘正中静脉注射对比剂后,用16层螺旋CT进行包括盆腔区的增强扫描,薄层重建图像用容积再现技术对髂-股动脉进行三维重建。测量动脉分叉到髂嵴连线、股骨头上缘连线的垂直距离及动脉分叉夹角。相同性别不同年龄组间采用单因素方差分析,相同年龄组不同性别采用两独立样本t检验,不同侧别间采用配对样本t检验。结果:腹主动脉分叉、左右髂总动脉分叉、左右股总动脉分叉到股骨头上缘连线的垂直距离男性A组分别为(132.5±12.8)mm、(87.1±14.9)mm、(88.8±11.3)mm、(43.4±13.7)mm、(41.5±15.0)mm,B组为(126.5±11.6)mm、(84.8±14.2)mm、(89.1±12.9)mm、(44.3±10.1)mm、(46.2±10.1)mm,C组为(115.6±10.7)mm、(80.3±14.3)mm、(82.3±13.6)mm、(39.1±10.0)mm、(40.4±10.0)mm,女性A组分别为(135.4±12.1)mm、(91.3±15.1)mm、(97.4±14.1)mm、(36.5±10.3)mm、(36.2±10.3)mm,B组为(129.8±12.7)mm、(92.7±12.5)mm、(96.0±13.3)mm、(36.5±10.8)mm、(35.8±10.9)mm,C组为(121.2±13.1)mm、(84.0±11.3)mm、(86.3±11.4)mm、(36.4±12.2)mm、(36.9±11.0)mm。除男性左髂总动脉分叉、女性左右股总动脉分叉到股骨头上缘连线的垂直距离外,不同年龄组间差异均有统计学意义(P<0.05)。腹主动脉分叉夹角、左右髂总动脉分叉夹角男性A组分别为(38.2±5.8)°、(26.6±16.9)°、(30.5±10.8)°,B组为(38.1±11.3)°、(25.3±10.8)°、(24.8±11.2)°,C组为(45.1±16.5)°、(25.8±12.5)°、(25.6±13.2)°,女性A组分别为(46.9±10.9)°、(28.2±13.5)°、(28.9±10.2)°,B组为(40.7±11.2)°、(20.3±10.3)°、(21.6±9.7)°,C组为(45.1±11.2)°、(21.0±9.9)°、(27.0±12.1)°,男女腹主动脉分叉夹角、男性左右髂总动脉分叉夹角不同年龄组间差异有统计学意义(P<0.05)。两侧对比三组的髂总动脉分叉点至股骨头上缘连线垂直距离差异均有统计学意义(P<0.05)。结论:16层螺旋CTA可对髂-股动脉进行准确测量,为介入诊疗提供数据。     

动脉粥样硬化模型中颈动脉分叉流场的数值模拟

目的实现动脉粥样硬化（atherosclerosis，AS）模型中颈动脉分叉流场的模拟。方法本文通过建立的动脉粥样硬化模型，连续切片HE染色后采集图像，以OLYSIA软件测定了颈动脉分叉各处的管径以及斑块的面积、周长和高度，采用Gambit软件建立了兔颈动脉分叉的正常对照和动脉粥样硬化斑块的几何模型。结果1）得到兔颈动脉分叉几何模型；2）以128 S^-1下测定的血液表观粘度作为血液粘度．其对照组和动脉粥样硬化模型组血管壁面最低剪切应力分别为1．140Pa、0．283Pa，对照组的颈动脉分叉处血管壁面最低剪切应力是动脉粥样硬化模型组的4．028倍。结论低血管壁面剪切应力，是动脉粥样硬化的危险性血流动力学因素。     

A new stent designed for carotid artery application. An experimental study

PURPOSE: To evaluate a new stent developed for treating arterial stenoses located adjacent to the bifurcation of the carotid artery. MATERIAL AND METHODS: Eight 4-cm-long nitinol stents, each with a diameter of 6 mm in its distal half and 9 mm in its proximal half, were tested in 4 pigs. In each animal, the abdominal aorta was catheterized through the left common carotid artery, and 2 stents were inserted into the right and left iliac arteries, respectively, with the wider portion in the common iliac artery and the narrower portion in the corresponding external iliac artery. The pigs were killed after 24 hours, or 1, 4 or 8 weeks, following control angiography. The arteries were examined macroscopically and by scanning electron microscopy. RESULTS: All stents remained in the intended position, fitting the arterial wall, following successive expansion to their maximum diameter and after 4 weeks were completely covered by endothelium. The arteries remained patent, with preserved flow to the side branches through the stent mesh. A small thrombus was found in I artery CONCLUSION: In animal experiments, the new stent was safely inserted over the arterial bifurcation, remained in place and was covered by endothelium while flow through side branches was preserved.     

Magnetic resonance imaging of atherosclerotic plaques using superparamagnetic iron oxide particles

Experimental data show accumulation of superparamagnetic iron oxide (SPIO) particles in atherosclerotic plaques. SPIO uptake occurred in plaques, suggesting an increased endothelial permeability and macrophage infiltrates as signs of inflammatory plaque activity. We incidentally observed SPIO uptake in aortic and arterial wall segments in patients who had originally received the magnetic resonance (MR) contrast agent for staging lymph node metastases. Twenty patients (19 male, 1 female; mean age, 64; range, 41-78 years) with bladder or prostate cancer underwent MR imaging (MRI) using a T2*-weighted high-resolution gradient-echo sequence prior to and 24-36 hours after intravenous injection of 2.6 mg of Fe/kg of SPIO (Sinerem). The aorta, both common external and internal iliac, as well as both superficial femoral arteries, were retrospectively analyzed for atherosclerotic wall changes. One patient was excluded. A positive finding was defined as an area of pronounced signal loss on postcontrast images clearly confined to the arterial wall, which was absent in the precontrast examination or increased in size. Such a finding was observed in one to three arteries in 7 of the 19 patients. The pronounced signal loss in the wall of the aorta and pelvic arteries seen in part of an elderly patient population after intravenous SPIO administration strongly suggests that this contrast agent accumulates in human atherosclerotic plaques.     

Effect of contrast enhancement on the measurement of carotid arterial lumen and wall volume using MRI

PURPOSE: To investigate whether gadolinium (Gd)-based contrast enhancement (CE) affects high-resolution magnetic resonance imaging (MRI) measurements of carotid arterial wall volume. MATERIALS AND METHODS: The common carotid artery (CCA), bifurcation, and internal carotid artery (ICA) of 50 consecutive patients were imaged using 1.5T MRI. T1-weighted (T1W) images were obtained before and after Gd administration. Pre- and post-CE measurements were compared among different arterial locations of the CCA, bifurcation, and ICA, and among different atherosclerotic lesion types. RESULTS: In comparison to pre-CE T1W images, post-CE images showed an increase in the apparent wall volume measurement of 28.2% (108.7 mm3 vs. 84.7 mm3, P < 0.001). The post-CE measurement increases in wall volume for the CCA, bifurcation, and ICA were 26.7%, 29.2%, and 28.0%, respectively. CONCLUSION: Gd CE causes a significant increase in the apparent volume of the carotid wall throughout multiple carotid artery locations, which may be associated with improved visibility or neovascularization.     

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.     

Association of vascular 18F-FDG uptake with vascular calcification.

Both calcification and FDG uptake have been advocated as indicators of atheroma. Atheromas calcify as cells in the lesion undergo apoptosis and necrosis during evolution of the lesion and at the end stage of the lesion. FDG concentrates in lesions due to the relatively dense cellularity in regions of inflammation of active atheromas. This investigation examines the geographic relationship of focal vascular (18)F-FDG uptake, as a marker of atherosclerotic inflammation, to arterial calcification detected by contemporaneous CT. METHODS: We reviewed PET/CT images from 78 patients who were referred for tumor staging for the presence of vascular (18)F-FDG uptake and vascular calcification. Arterial wall (18)F-FDG accumulation greater than adjacent blood-pool activity was considered inflammation. Arterial attenuation of >130 Hounsfield units was considered calcification. Sites in the ascending and descending aorta, the carotid and iliac arteries, and the coronary territories were examined on the emission, CT, and fusion images on a point-by-point basis. When lesions were seen, we evaluated whether they were overlapping or discrete. RESULTS: The (18)F-FDG arterial distribution was consistent with established atherosclerotic topography, with increased uptake in the thoracic aorta, at the carotid bifurcation, and in the proximal coronary vessels. Arteries typically displayed a patchwork of normal vessel, focal inflammation, or calcification; inflammation and calcification overlapped in <2% of cases. Arterial inflammation preceded calcification, in terms of mean patient age. Coronary inflammation was more prevalent in patients with more cardiovascular risk factors. CONCLUSION: Vascular calcification and vascular metabolic activity rarely overlap, suggesting these findings represent different stages in the evolution of atheroma.     

Fly through ultrasound imaging in assessment of carotid atherosclerosis: a pictorial essay

To assess fly through ultrasound imaging (FTUS) in evaluation of carotid artery atherosclerosis, we prospectively performed conventional sonography and FTUS of the carotid artery on 66 patients with suspicion for atherosclerosis. Characteristics of arterial intima, atherosclerotic plaque, luminal narrowing, and carotid stent graft displayed on FTUS were compared with that on conventional sonography. On FTUS, normal carotid artery wall was smooth in appearance, mild carotid atherosclerosis appeared focal arterial wall irregularity and small plaque formation, arterial luminal reduction resulted from progressive artery plaques, and carotid stent had irregular inner lumen and tight fit against the arterial wall. A total of 38 plaques were detected by conventional sonography, while 48 plaques were depicted by FTUS in 25 patients. Using magnetic resonance angiography as a reference standard, 17 cases with >50% and 3 cases with < 50% luminal reduction measured on FTUS. However, all those 20 cases were measured with >50% luminal reduction on conventional sonography. Compared with conventional sonography, FTUS can dynamically display intraluminal structure on real-time three-dimensional imaging morphologically to improve the accuracy in detecting atherosclerotic plaque and assessing luminal narrowing in the carotid artery.     

糖尿病终末期肾病颈动脉粥样硬化的危险因素分析

目的探讨糖尿病终末期肾病(ESRD-DM)血液透析患者颈动脉粥样硬化(AS)的危险因素。方法检测57例原发于糖尿病的血液透析(HD)患者一般临床指标,同时应用高分辨彩色B超测患者颈动脉内膜-中层厚度(CCA-IMT)及粥样硬化斑块情况。结果粥样硬化斑块阳性的ESRD-DM的HD患者血浆白蛋白(A lb)显著低于粥样硬化斑块阴性患者;而HD时间、低密度脂蛋白(LDL)、C-反应蛋白(CRP)、颈动脉IMT显著高于粥样硬化斑块阴性的患者;患者颈AS的危险因素为LDL、CRP。结论ESRD-DM的HD患者营养状况及低蛋白血症明显,血CRP升高、血脂异常,AS明显而严重,AS可能与CRP、LDL有关。