The importance of patient-specific regionally varying wall thickness in abdominal aortic aneurysm biomechanics.
The importance of patient-specific regionally varying wall thickness in abdominal aortic aneurysm biomechanics.
复制标题
患者特定区域不同的壁厚度在腹主动脉瘤生物力学中的重要性。
DOI：
10.1115/1.4024578
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
Finol,EnderA
中科院分区：
文献类型：
--
作者：
Raut,SamarthS;Jana,Anirban;DeOliveira,Victor;Muluk,SatishC;Finol,EnderA
腹主动脉瘤（AAA）是一种血管疾病，使用基于生物力学的评估进行患者特异性风险评估是一种很有前途的临床治疗方法。在影响该评价的诸多因素中，AAA壁厚有望成为一个重要因素。然而，区域差异的患者特异性壁厚并没有被纳入AAA生物力学的建模特征。据我们所知，目前的工作是第一次将患者特定的可变壁厚纳入AAA壁力学估计，而没有对其分布进行潜在的经验假设。在这项工作中，我们提出了一种将区域变化壁厚（“PSNUT”建模策略）纳入AAA有限元建模的新方法，并将该方法应用于28个AAA几何形状的直径匹配队列，以评估源自均匀壁厚的传统假设的壁力学差异。对于后者，我们使用了文献推导的群体平均壁厚（1.5 mm，即“UT”策略）以及患者特异性可变壁厚的空间平均值（即“PSUT”策略）。对于三种不同的壁厚建模策略，壁力学通过四个生物力学参数进行评估：第一主应力的空间最大值、应变、应变能密度和位移。我们进行了统计分析，以解决使用任何均匀壁厚模型与患者特定的区域变化壁厚模型相比导致显著不同的生物力学参数的假设。与PSNUT策略相比，UT建模策略在第一主应力（p = 0.002）、应变（p = 0.0005）和应变能密度（p = 7.83 e-5）的空间最大值上有统计学差异，但在位移（p = 0.773）上无统计学差异。同样，PSUT模型策略与PSNUT模型策略在第一主应力（p = 9.68 e-7）、应变（p = 1.03 e-8）、应变能密度（p = 9.94 e-8）和位移（p = 0.0059）的空间最大值上也存在显著差异。在第一主应力（p = 0.285）、应变（p = 0.152）、应变能密度（p = 0.222）和位移（p = 0.0981）的空间最大值方面，UT策略与PSUT策略的差异无统计学意义。如果AAA有限元分析的重点是估计峰值生物力学参数，如应力、应变和应变能密度，本研究强烈建议使用由腹部计算机断层扫描（CT）分割得出的患者特异性区域变化壁厚。
Abdominal aortic aneurysm (AAA) is a vascular condition where the use of a biomechanics-based assessment for patient-specific risk assessment is a promising approach for clinical management of the disease. Among various factors that affect such assessment, AAA wall thickness is expected to be an important factor. However, regionally varying patient-specific wall thickness has not been incorporated as a modeling feature in AAA biomechanics. To the best our knowledge, the present work is the first to incorporate patient-specific variable wall thickness without an underlying empirical assumption on its distribution for AAA wall mechanics estimation. In this work, we present a novel method for incorporating regionally varying wall thickness (the “PSNUT” modeling strategy) in AAA finite element modeling and the application of this method to a diameter-matched cohort of 28 AAA geometries to assess differences in wall mechanics originating from the conventional assumption of a uniform wall thickness. For the latter, we used both a literature-derived population average wall thickness (1.5 mm; the “UT” strategy) as well as the spatial average of our patient-specific variable wall thickness (the “PSUT” strategy). For the three different wall thickness modeling strategies, wall mechanics were assessed by four biomechanical parameters: the spatial maxima of the first principal stress, strain, strain-energy density, and displacement. A statistical analysis was performed to address the hypothesis that the use of any uniform wall thickness model resulted in significantly different biomechanical parameters compared to a patient-specific regionally varying wall thickness model. Statistically significant differences were obtained with the UT modeling strategy compared to the PSNUT strategy for the spatial maxima of the first principal stress (p = 0.002), strain (p = 0.0005), and strain-energy density (p = 7.83 e–5) but not for displacement (p = 0.773). Likewise, significant differences were obtained comparing the PSUT modeling strategy with the PSNUT strategy for the spatial maxima of the first principal stress (p = 9.68 e–7), strain (p = 1.03 e–8), strain-energy density (p = 9.94 e–8), and displacement (p = 0.0059). No significant differences were obtained comparing the UT and PSUT strategies for the spatial maxima of the first principal stress (p = 0.285), strain (p = 0.152), strain-energy density (p = 0.222), and displacement (p = 0.0981). This work strongly recommends the use of patient-specific regionally varying wall thickness derived from the segmentation of abdominal computed tomography (CT) scans if the AAA finite element analysis is focused on estimating peak biomechanical parameters, such as stress, strain, and strain-energy density.
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影响因子：
4.3
作者：
Fillinger, MF;Marra, SP;Kennedy, FE
通讯作者：
Kennedy, FE
DOI：
10.1016/j.cma.2009.02.004
发表时间：
2009-09-15
影响因子：
7.2
作者：
Taylor CA;Humphrey JD
通讯作者：
Humphrey JD
影响因子：
3.8
作者：
Maier, A.;Gee, M. W.;Wall, W. A.
通讯作者：
Wall, W. A.
影响因子：
3.8
作者：
Shum, Judy;DiMartino, Elena S.;Finol, Ender A.
通讯作者：
Finol, Ender A.