Noninvasive two-dimensional strain imaging of arteries:: Validation in phantoms and preliminary experience in carotid arteries in vivo
Noninvasive two-dimensional strain imaging of arteries:: Validation in phantoms and preliminary experience in carotid arteries in vivo
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DOI：
10.1016/j.ultrasmedbio.2006.09.009
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发表时间：
2007-04-01
影响因子：
2.9
通讯作者：
De Korte, Chris L.
中科院分区：
文献类型：
--
作者：
Ribbers, Hermine;Lopata, Richard G. P.;De Korte, Chris L.
心脏病和中风是西方世界的主要死因。颈动脉粥样硬化是中风最重要的预测因素。弹性成像是一种评估动脉粥样硬化斑块的组成和易损性的技术。与血管内应用相反，超声束和径向应变在非侵入性采集中不对齐。在这项研究中，2D位移和应变图像被确定并用于计算径向和周向应变。使用配备11_3L（3至11 MHz）线阵换能器和射频接口的Philips SONOS 7500实时3D超声系统采集射频数据。在不同腔内压力下，在水箱中测量均匀的中空圆柱体模[20%明胶，1% SiC散射体（10 [cm]）]。此外，对患者（n = 12）进行测量，以评价该技术的体内适用性。在体模和患者中进行纵向和横截面记录。应变沿着超声波束（轴向应变），确定使用互相关分析的信号窗口从前和后压缩数据。对于横向应变，使用插值在采集的线之间生成新的超声线。应用基于互相关的搜索算法来确定侧向位移和应变。体模中的纵向轴向应变图像显示从管腔-血管壁界面到外部区域的应变减小，可以通过1/r（2）关系来描述。横向应变图像显示在该方向上没有应变，表明平面应变情况。在横截面视图中，在12点和6点的区域中观察到材料的压缩，而在3点和9点的区域中观察到膨胀。这种模式是根据理论，但只能部分校正：在过渡区，零轴向应变测量。横向应变图像显示互补模式。在患者中，在非动脉粥样硬化的动脉壁中观察到低应变。动脉粥样硬化斑块中存在高应变区和低应变区。高质量的弹性成像在纵向和横截面视图中生成。总之，2D无创弹性成像的动脉粥样硬化斑块是可行的。体模研究显示弹性图符合理论。需要额外的体内验证来评估该技术用于识别斑块易损性和组成的价值。
Cardiac disease and stroke are the major causes of death in the Western World. Atherosclerosis of the carotid artery is the most important predictor of stroke. Elastography is a technique to assess the composition and vulnerability of an atherosclerotic plaque. Contrary to intravascular applications, the ultrasound beam and radial strain are not aligned in noninvasive acquisitions. In this study, 2D displacement and strain images were determined and used to calculate the radial and circumferential strain. Rf-data were acquired using a Philips SONOS 7500 live 3D ultrasound system, equipped with an 11_3L (3 to 11 MHz) linear array transducer and rf-interface. A homogeneous, hollow cylinder phantom [20% gelatin, 1% SiC scatterers (10 [cm)] was measured in a water tank at different intraluminal pressures. In addition, measurements in patients (n = 12) were made to evaluate the in vivo applicability of the technique. Longitudinal and cross-sectional recordings were made, both in phantoms and patients. Strain along the ultrasound beam (axial strain) was determined using cross-correlation analysis for signal-windows from both the pre- and postcompression data. For lateral strain, new ultrasound lines were generated between the acquired lines using interpolation. A cross-correlation based search algorithm was applied to determine lateral displacement and strain. Longitudinal axial strain images in the phantom showed a decreasing strain from the lumen- vessel wall interface to the outer region that can be described by a 1 over r(2) relationship. The lateral strain image showed no strain in this direction indicating a plane strain situation. In the cross-sectional view, compression of the material in regions at 12 and 6 o'clock was observed, whereas expansion was observed in regions at 3 and 9 o'clock. This pattern is in accordance with theory, but can only be partly corrected for: in the transition regions, zero axial strain was measured. The lateral strain image showed a complementary pattern. In patients, low strain was observed in nonatherosclerotic artery walls. High and low strain regions were found in atherosclerotic plaques. High quality elastograms were generated both in longitudinal and cross-sectional views. In conclusion, 2D noninvasive elastography of atherosclerotic carotid plaques is feasible. Phantom studies revealed elastograms in accordance with theory. Additional in vivo validation is needed to assess the value of this technique for identifying plaque vulnerability and composition.