Simulation of artificial anal sphincter motion and interaction with intestinal environment using SOFA

Area of Science:

• Biomedical Engineering
• Medical Device Simulation
• Computational Mechanics

Background:

• Artificial anal sphincter (AAS) is an implantable device for fecal incontinence.
• Simulation aids research and reduces biological testing for AAS development.
• Further exploration of AAS clamping motion and sensor interaction with the intestine is needed.

Purpose of the Study:

• To present a simulation of the artificial anal sphincter's clamping and sensing.
• To model the interaction between the AAS and the intestinal environment.
• To validate the simulation using in vitro experiments.

Main Methods:

• Simulation Open Framework Architecture (SOFA) was used for modeling.
• A finite element model of the intestine was created based on soft tissue properties.
• In vitro experiments were conducted to validate simulation accuracy.

Main Results:

• The AAS sensor system demonstrated good performance during clamping and fecal accumulation.
• Optimal sensory capabilities were observed at AAS roll angles between 20° and 40°.
• Simulation showed a 10%-20% mean absolute error compared to experimental sensor forces.

Conclusions:

• The novel simulation accurately models AAS interaction with the intestinal environment.
• Simulation data can guide improvements in AAS sensor perception.
• This work supports further research and development of artificial anal sphincters.