Christiansen, David L.
Ryan, Peter L.
Other Advisors or Committee Members
Elder, Steven H.
Date of Degree
Dissertation - Open Access
Doctor of Philosophy
James Worth Bagley College of Engineering
Department of Agricultural and Biological Engineering
Pelvic organ prolapse is characterized by the failure of vaginal wall support and protrusion of the pelvic organs through the vaginal orifice. Exact etiology of pelvic organ prolapse is not completely understood. The surgical procedures for pelvic organ prolapse utilize various biomaterials for holding the organs in place. However, the biomaterials used for restoring these organs have a high rate of failure in a complicated anatomical and biomechanical environment. With the given issues at hand, animal models are the best answer for understanding the pathophysiology of prolapse, and determining the cause of failure of these surgical interventions. For this study, we are investigating sheep as an animal model for human pelvic organ prolapse. We compared the anatomy of the sheep pelvic floor with humans. We found that anatomical parameters are a good measure/biomarker for estimating structural and anatomical changes in the body of the animal. As the anatomical measurements are applied to human vaginal prolapse, we can apply the same principles in sheep and further explore the feasibility of using sheep as an animal model for prolapse. Additionally, we evaluated location dependent biomechanical properties of the sheep vaginal tract. We have characterized the structure-property relationship of sheep vaginal wall tissue in the top third and middle third regions. We found that in contrast to current published research, sheep vaginal tissues are anisotropic in nature. This anisotropic characteristic of the sheep vaginal wall tissue is a direct function of the microstructural arrangement of collagen, elastin, smooth muscle and other extracellular matrix components. We also developed decellularized scaffolds as potential biomaterials, which can be potentially utilized in prolapse surgeries. We developed three different types of vaginal tissue scaffolds using SDS, Triton X-100, and trypsin for reconstructive surgery applications. During the decellularization, all of the cellular components are removed, which leaves the acellular ECM behind. We analyzed the biomechanical properties and microstructural properties of these scaffolds and found that the SDS samples were better in all aspects of the preclinical evaluation. Future studies will aim at applying the anatomical and biomechanical techniques used in this study to prolapsed sheep vaginal wall tissues.
Patnaik, Sourav, "Investigation of Sheep Reproductive Tract as an Animal Model for Pelvic Organ Prolapse and Urogyencological Research" (2015). Theses and Dissertations MSU. 2851.