Multifrequency tabletop magnetic resonance elastography for ex-vivo characterization of murine intestinal tissue...

Magnetic resonance elastography (MRE) is an established diagnostic tool for assessing liver and intestinal fibrosis. However, reliable biomechanical characterization of murine gastrointestinal (GI) tract remains challenging due to its small size, high compliance, and the lack of standardized protocols and reference data. Tabletop magnetic resonance elastography (ttMRE) provides a scalable, cost-effective ex-vivo approach to quantify viscoelastic properties of small samples using multifrequency shear wave measurements while preserving the tissue's architecture. Here, we establish the first ttMRE protocol for the ex-vivo biomechanical assessment of the murine ileum and colon. The protocol enables measurements of shear wave speed and shear wave penetration frate in the frequency range between 0.8 and 4 kHz for viscoelastic dispersion analysis based on different rheological models. Among two-parameter models, the springpot model best fitted the experimental data yielding similar median shear modulus (μ_SP) values of 4.5 [3.8, 4.7] kPa and 4.8 [4.3, 5.4] kPa and power law-exponent 0.56 [0.52, 0.59] and 0.58 [0.57, 0.60] for colon and ileum, respectively. Our work establishes a ttMRE protocol and provides preliminary baseline values for murine intestinal biomechanical properties. The method may facilitate investigations of disease progression, extracellular matrix remodeling, and therapeutic response in mouse models of inflammatory bowel diseases.