Finite-element modeling of soft tissue rolling indentation

Area of Science:

• Robotics and Mechanical Engineering
• Biomedical Engineering
• Computational Mechanics

Background:

• Minimally invasive surgery (MIS) often involves loss of haptic and tactile feedback.
• Rolling mechanical imaging using wheeled probes shows promise for restoring this feedback.
• Understanding wheel-tissue interaction dynamics is crucial for signal interpretation.

Purpose of the Study:

• To develop and validate a finite-element (FE) model for simulating wheel-rolling tissue deformations.
• To precisely locate abnormalities within soft tissues using a rolling FE model (RFEM).
• To enhance surgeons' diagnostic abilities in MIS.

Main Methods:

• A rolling FE model (RFEM) was developed using ABAQUS FE software.
• Soft tissue was modeled as a nonlinear hyperelastic material with geometrical nonlinearity.
• The RFEM was validated using a silicone phantom and a porcine kidney sample.

Main Results:

• The RFEM accurately predicted wheel-tissue interaction forces during rolling indentation.
• The model successfully identified the location and depth of simulated tumors.
• The FE model demonstrated good accuracy in predicting tissue deformations.

Conclusions:

• The proposed RFEM provides an accurate method for simulating wheel-tissue interactions.
• This technology can significantly improve the localization of soft tissue abnormalities.
• The RFEM has the potential to enhance diagnostic capabilities in robotic-assisted MIS.