TY - JOUR
T1 - Characterizing poroelasticity of biological tissues by spherical indentation
T2 - An improved theory for large relaxation
AU - Wang, Ming
AU - Liu, Shaobao
AU - Xu, Zhimin
AU - Qu, Kai
AU - Li, Moxiao
AU - Chen, Xin
AU - Xue, Qing
AU - Genin, Guy M.
AU - Lu, Tian Jian
AU - Xu, Feng
N1 - Publisher Copyright:
© 2020
PY - 2020/5
Y1 - 2020/5
N2 - Flow of fluids within biological tissues often meets with resistance that causes a rate- and size-dependent material behavior known as poroelasticity. Characterizing poroelasticity can provide insight into a broad range of physiological functions, and is done qualitatively in the clinic by palpation. Indentation has been widely used for characterizing poroelasticity of soft materials, where quantitative interpretation of indentation requires a model of the underlying physics, and such existing models are well established for cases of small strain and modest force relaxation. We showed here that existing models are inadequate for large relaxation, where the force on the indenter at a prescribed depth at long-time scale drops to below half of the initially peak force (i.e., F(0)/F(∞) > 2). We developed an indentation theory for such cases of large relaxation, based on Biot theory and a generalized Hertz contact model. We demonstrated that our proposed theory is suitable for biological tissues (e.g., porcine liver, spleen, kidney, skin and human cirrhosis liver) with both small and large relaxations. The proposed method would be a powerful tool to characterize poroelastic properties of biological materials for various applications such as pathological study and disease diagnosis.
AB - Flow of fluids within biological tissues often meets with resistance that causes a rate- and size-dependent material behavior known as poroelasticity. Characterizing poroelasticity can provide insight into a broad range of physiological functions, and is done qualitatively in the clinic by palpation. Indentation has been widely used for characterizing poroelasticity of soft materials, where quantitative interpretation of indentation requires a model of the underlying physics, and such existing models are well established for cases of small strain and modest force relaxation. We showed here that existing models are inadequate for large relaxation, where the force on the indenter at a prescribed depth at long-time scale drops to below half of the initially peak force (i.e., F(0)/F(∞) > 2). We developed an indentation theory for such cases of large relaxation, based on Biot theory and a generalized Hertz contact model. We demonstrated that our proposed theory is suitable for biological tissues (e.g., porcine liver, spleen, kidney, skin and human cirrhosis liver) with both small and large relaxations. The proposed method would be a powerful tool to characterize poroelastic properties of biological materials for various applications such as pathological study and disease diagnosis.
KW - Diffusion coefficient
KW - Mechanical characterization
KW - Porous biomaterials
KW - Shear modulus, Poisson ratio
UR - http://www.scopus.com/inward/record.url?scp=85081653836&partnerID=8YFLogxK
U2 - 10.1016/j.jmps.2020.103920
DO - 10.1016/j.jmps.2020.103920
M3 - Article
AN - SCOPUS:85081653836
SN - 0022-5096
VL - 138
JO - Journal of the Mechanics and Physics of Solids
JF - Journal of the Mechanics and Physics of Solids
M1 - 103920
ER -