title: Experimental analysis of the mechanical behavior of the viscoelastic porcine pancreas and preliminary case study on the human pancreas.
abstract: The aim of this article is to study the mechanical properties of the pancreas. Up to now, the mechanical properties of the pancreas are not sufficiently characterized. The possibility of intraoperative mechanical testing of pathological pancreata will allow the classification of pancreatic diseases in the future. The application of mechanical parameters instead of the intraoperative frozen section analysis shortens waiting times in the operating room. This study proves the general applicability of shear rheology for the determination of the mechanical properties of pancreas and the assessment of graft quality for transplantation. Porcine and human pancreas samples were examined ex vivo and a nonlinear viscoelastic behavior was observed. Pancreas was found to be more viscous than liver but both abdominal organs showed a similar flow behavior. The shear deformation dependence of healthy human pancreas was similar to porcine pancreas. An increase in the post-mortem time led to an increase in the complex modulus for a post-mortem time up to 8.5 days. Histological investigations showed that an increased amount of collagen coincides with the stiffening of the pancreatic tissue.
authors.affiliation: Clinic for General, Visceral and Vascular Surgery, University Clinic Magdeburg, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Wex
authors.affiliation: Clinic for General, Visceral and Vascular Surgery, University Clinic Magdeburg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Fröhlich
authors.affiliation: Center for Pathology and Forensic Medicine, University Clinic Magdeburg, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Brandstädter
authors.affiliation: Clinic for General, Visceral and Vascular Surgery, University Clinic Magdeburg, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Bruns
authors.affiliation: Clinic for General, Visceral and Vascular Surgery, University Clinic Magdeburg, Germany. Electronic address: anke.stoll@med.ovgu.de.
authors.forename: A
authors.initials: A
authors.lastname: Stoll
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D004548:Elasticity; D006801:Humans; D008099:Liver; D008422:Materials Testing; D009929:Organ Size; D010179:Pancreas / Q000166:cytology; D013045:Species Specificity; D013552:Swine; D014783:Viscosity
keywords: Pancreas Transplantation; Pancreatitis; Shear Rheology; Soft tissue mechanics