Department of Biomedical Engineering, Boston University, 44 Cummington Street, Boston, MA 02215, USA; Hearing Research Center, Boston University, 44 Cummington Street, Boston, MA 02215, USA.
Department of Mechanical Engineering, Boston University, 110 Cummington Street, Boston, MA 02215, USA.
J Biomech. 2014 Apr 11;47(6):1270-7. doi: 10.1016/j.jbiomech.2014.02.025. Epub 2014 Feb 20.
We describe a method to use point-stiffness (PtSt) measurements, i.e., indentation measurements, to obtain elastic moduli of different organ of Corti (OC) tissues. A detailed finite element (FE) model of the OC is used to account for geometric effects in the indentation measurements. We also present a sensitivity analysis, performed within a Bayesian estimation framework, that can be used to improve experimental design. The sensitivity analysis shows that the basilar membrane (BM) PtSt is most sensitive to changes in the BM properties and to changes in the pillar cells (PC) properties. This result suggests that the BM and the PC dominate the macromechanics of the OC. The most likely values of the Young׳s modulus predicted for the middle turn for the BM arcuate, BM pectinate, and the PC are found to be 935 KPa (range 640-1360 KPa), 300 KPa (range 190-460 KPa), and 3 GPa (range 1-9 GPa), respectively.
我们描述了一种使用点刚度(PtSt)测量值(即压痕测量值)来获得不同耳蜗组织(OC)弹性模量的方法。使用详细的有限元(FE)模型来解释压痕测量中的几何效应。我们还提出了一种基于贝叶斯估计框架的灵敏度分析,可以用于改进实验设计。灵敏度分析表明,基底膜(BM)的 PtSt 对 BM 特性和柱细胞(PC)特性的变化最敏感。这一结果表明,BM 和 PC 主导着 OC 的宏观力学。对于 BM 弧形、BM 梳状和 PC 的中间转角,预测的杨氏模量的最可能值分别为 935 KPa(范围 640-1360 KPa)、300 KPa(范围 190-460 KPa)和 3 GPa(范围 1-9 GPa)。