On the Status Quo in Mechanical Experimentation and Structural Characterization of the Stomach

Abstract

The prevalence of gastric diseases is rising worldwide, especially among young adults. Many conditions of the stomach seem to be closely related to its mechanical properties, geometry, and underlying microstructure. Due to the complex coupling between these aspects, effective diagnosis and treatment are often difficult. Predictive material models of the stomach (wall) and simulations based on these could significantly contribute to the overall disease understanding, treatment choice, and surgical planning. However, the development of such material models requires experimental data on the mechanical behavior and structure. For this purpose, this review discusses current experimental approaches for the characterization of the stomach. First, all relevant anatomical, physiological, and mechanical aspects are summarized. Based on its complex organ geometry and regionally varying wall architecture, all experimental studies are grouped in terms of sample scale, differentiating between organ- and tissue-level. Further, the review comprises both mechanical and structural investigations for each sample scale. In particular, each experimental approach is evaluated in terms of working principles and applicability to gastric tissue. Key findings from different studies derived from the same technique are compared and discussed in context with the gastric physiology. Finally, current research gaps are identified, and future directions of gastric research are envisioned with the aim of fully characterizing the mechanical behavior and hierarchical structure of this vital organ. This review offers practical guidance for researchers in defining future experimental designs and a concise summary of existing datasets for constitutive modeling of the stomach