Skin Tissue Deformation and Permeability related to Pressure Driven Flow*

Skin tissue is a porous, permeable, fluid filled, and deformable media.  However, currently there is limited understanding of the characteristics of fluid flow through skin tissue.  There are several motivations for gaining a better understanding of how fluid flows through skin tissue.  The fundamental knowledge of how fluid flows through skin tissue can be useful to improve intradermal injection technologies, to provide a reference for comparison when designing artificial skin grafts, and for future skin tissue related biomedical applications and inventions. 

In this study, we apply a pressure gradient to induce fluid flow across skin tissue, while simultaneously using Optical Coherence Tomography (OCT) to visualize the local deformation of the skin tissue and Digital Image Correlation (DIC) to calculate the resulting strain field in the skin tissue.   It has been observed that the initial permeability of skin tissue is on the order of 10^-14 m², and that the skin’s permeability changes as the tissue deforms (measured using OCT & DIC) under the driving fluid flow.  The aim of this work is to develop a model for how pressure gradient and fluid flow strain skin tissue and how changes in tissue strain affect the tissue’s permeability.