Validations of the microchannel flow model for characterizing vascularized tissues.

Kevin J. Parker,Sedigheh S. Poul,Juvenal Ormachea,Stefanie J. Hollenbach

doi:10.3390/fluids5040228

Abstract

The microchannel flow model postulates that stress-strain behavior in soft tissues is influenced by the time constants of fluid-filled vessels related to Poiseuille’s law. A consequence of this framework is that changes in fluid viscosity and changes in vessel diameter (through vasoconstriction) have a measurable effect on tissue stiffness. These influences are examined through the theory of the microchannel flow model. Then, the effects of viscosity and vasoconstriction are demonstrated in gelatin phantoms and in perfused tissues, respectively. We find good agreement between theory and experiments using both a simple model made from gelatin and from living, perfused, placental tissue ex vivo.

Highlights

Tissue elasticity measurements can provide valuable information related to pathological changes in tissues
The results show that castor oil is almost 12 times more viscous than olive oil
According to the microchannel flow model (MCFM) derivation, each vessel in a vasculature is associated with a characteristic time constant τchar and a branching vasculature, comprised of different vessels from smallest to largest, introduces a spectrum of time constants that contribute to the behavior of the soft tissue under study

Summary

Introduction

Tissue elasticity measurements can provide valuable information related to pathological changes in tissues. Elastography has been extensively applied to the diagnosis of normal and abnormal conditions of tissues such as breast, liver, prostate, thyroid and placenta [1,2]. Athanasiou et al [3], in a study on 48 women with benign or malignant breast lesions, showed that elasticity of malignant lesions was higher than benign cases. Figure, where where an an elastic elastichomogeneous homogeneous material material contains contains aa small small fluid-filled fluid-filled channel open on only one side. 1. An. Anideal idealmodel modelof ofan anelastic, elastic,isotropic isotropicblock blockwith withaa single single interior interior fluid-filled fluid-filled channel channel of of Figure radius r and length. L is considered for the stress derivation in the MCFM. The block cross-sectional radius r and length L is considered for the stress derivation in block cross-sectional area and and height are denoted

Methods

Results

Discussion

Conclusion