Viscoelastic characterization of in-vitro canine liver tissue

Samples of in-vitro canine liver tissue have been subjected to mechanical testing in order to determine their viscoelastic properties, namely, the frequency-dependent complex modulus. Samples include normal tissue, as well as thermal lesions prepared by radiofrequency ablation at various temperatures and cook times. Results are fitted according to the Kelvin-Voigt and Kelvin-Voigt fractional derivative models. The data agrees much better with the Kelvin-Voigt fractional derivative model, suggesting that this model may better represent the viscoelastic properties of some soft tissues. Results are then used in introducing the concept of the complex modulus contrast, whose applications to elastography are discussed.