An inverse method for imaging the local elasticity of atherosclerotic coronary plaques
An inverse method for imaging the local elasticity of atherosclerotic coronary plaques
复制标题
DOI：
10.1109/titb.2007.907980
复制
发表时间：
2008-05-01
影响因子：
--
通讯作者：
van der Steen, Antonius F. W.
中科院分区：
文献类型：
--
作者：
Baldewsing, Radjkumarsing Radj A.;Danilouchkine, Mikhail G.;van der Steen, Antonius F. W.
薄帽纤维粥样斑块（TCFA）的破裂是急性冠状动脉事件的主要原因。TCFA有一个致血栓的软脂质核心，通过一个薄的、可能发炎的硬帽与血流隔离。大多数动脉粥样硬化斑块在整体结构组成方面类似于TCFA，但具有更复杂、异质的形态。材料分布的评估对于量化斑块的机械稳定性和确定斑块稳定药物的作用至关重要。我们描述了一种新的自动逆弹性方法，血管内超声（IVUS）modulography，这是能够重建的异质杨氏模量分布。弹性图（即，空间应变分布）是该方法的输入，并且使用临床上可用的技术IVUS弹性成像来测量。我们的方法采用了一种新的分而治之的策略，允许重建TCFA以及具有局部软组织，弱化组织区域的异质斑块。该方法被施加到离体弹性图，这是从死后的人冠状动脉斑块的横截面模拟。为了证明该方法的临床可行性，从人类动脉粥样硬化冠状动脉测量弹性图进行了分析。一个弹性图是在体外测量的;另一个是在体内测量的。该方法近似所有模拟斑块的真实杨氏模量分布，而体外重建与组织学一致。总之，IVUS模块化成像结合IVUS弹性成像具有强大的潜力成为检测斑块、评估与其破裂倾向相关的信息以及成像其异质弹性材料成分的全方位模式。
The rupture of thin-cap fibroatheroma (TCFA) plaques is a major cause of acute coronary events. A TCFA has a trombogenic soft lipid core, shielded from the blood stream by a thin, possibly inflamed, stiff cap. The majority of atherosclerotic plaques resemble a TCFA in terms of overall structural composition, but have a more complex, heterogeneous morphology. An assessment of the material distribution is vital for quantifying the plaque's mechanical stability and for determining the effect of plaque-stabilizing pharmaceutical agents. We describe a new automated inverse elasticity method, intravascular ultrasound (IVUS) modulography, which is capable of reconstructing a heterogeneous Young's modulus distribution. The elastogram (i.e., spatial strain distribution) of the plaque is the input for the method, and is measured using the clinically available technique, IVUS elastography. Our method incorporates a novel divide-and-conquer strategy, allowing the reconstruction of TCFAs as well as heterogeneous plaques with localized regions of soft, weakened tissue. The method was applied to ex vivo elastograms, which were simulated from the cross sections of postmortem human coronary plaques. To demonstrate the clinical feasibility of the method, measured elastograms from human atherosclerotic coronary arteries were analyzed. One elastogram was measured in vitro; the other, in vivo. The method approximated the true Young's modulus distribution of all simulated plaques, while the in vitro reconstruction was in agreement with histology. In conclusion, the IVUS modulography in combination with the IVUS elastography has strong potential to become an all-encompassing modality for detecting plaques, for assessing the information related to their rupture-proneness, and for imaging their heterogeneous elastic material composition.