PURPOSE: As obesity has reached pandemic proportions worldwide, improving technical solutions for its treatment requires robust planning and numerical modelling. Yet existing material models obtained from biaxial tensile test are scarce and based only on frozen human or porcine samples, without histological quantitative consideration. Our objective was to generate fresh-human biaxial data including microstructure orientation/dispersion and provide patient-specific material models suitable for biofidelic FE modelling. METHODS: ) and three displacement ratios (1:1, 1:2, 2:1). Full-field strain was measured by digital image correlation. Collagen orientation/dispersion were extracted from histology using machine learning techniques. An incompressible anisotropic hyperelastic law (neo-Hookean matrix + two fibre families) was fitted per specimen across all ratios/directions. RESULTS: > 0.7 both in circumferential and longitudinal in respectively 85 and 81% of specimen. CONCLUSION: Fresh-human, full-field biaxial data coupled to quantified collagen architecture yield specimen-level parameters and region-specific safe-stretch thresholds, enabling biofidelic, patient-specific FE simulations of gastric procedures and device-tissue interaction.
Fournier et al. (Wed,) studied this question.