An enhanced interactive endoscope model based on position-based dynamics and Cosserat rods for colonoscopy simulation

Abstract

Virtual simulators play a significant role in training surgeons for endoscopic procedures, improving their abilities in real-world scenarios while reducing patient exposure. However, due to the complexity of the organs’ behavior, building realistic virtual simulators is still a challenge. In this paper, we propose an approach to modeling the endoscope and its interaction with the colon with a focus on compatibility between colon simulation, endoscope simulation, and user interaction. Instead of using a traditional physics-based approach, which is computationally expensive, we rely on efficient position-based methods that were originally built for video games, where high accuracy is traded for interactive plausibility. We propose a Cosserat rod constraint to model the endoscope and designed a user-centered interface that allows the simulator to run on commodity computers instead of dedicated training hardware. We implemented our model and interface on Unity and evaluated our virtual endoscope for compatibility with a deformable colon. Results show that the model performs in real-time, the dynamic elongation of the scope is stable, and the typical maneuvers made in total colonoscopy can be effectively made with the interface.