Position-Based Dynamics Simulator of Brain Deformations for Path Planning and Intra-Operative Control in Keyhole Neurosurgery

Abstract

Many tasks in robot-assisted surgery require planning and controlling manipulators' motions that interact with highly deformable objects. This study proposes a realistic, timebounded simulator based on Position-based Dynamics (PBD) simulation that mocks brain deformations due to catheter insertion for pre-operative path planning and intra-operative guidance in keyhole surgical procedures. It maximizes the probability of success by accounting for uncertainty in deformation models, noisy sensing, and unpredictable actuation. The PBD deformation parameters were initialized on a parallelepiped-shaped simulated phantom to obtain a reasonable starting guess for the brain white matter. They were calibrated by comparing the obtained displacements with deformation data for catheter insertion in a composite hydrogel phantom. Knowing the gray matter brain structures' different behaviors, the parameters were fine-tuned to obtain a generalized human brain model. The brain structures' average displacement was compared with values in the literature. The simulator's numerical model uses a novel approach with respect to the literature, and it has proved to be a close match with real brain deformations through validation using recorded deformation data of in-vivo animal trials with a mean mismatch of 4.73±2.15%. The stability, accuracy, and real-time performance make this model suitable for creating a dynamic environment for KN path planning, pre-operative path planning, and intra-operative guidance.

Toward a Digital Twin for Arthroscopic Knee Surgery: A Systematic Review

“…However, it ignores the accurate modeling of the physical properties of soft tissues. This geometrics-based approach has recently been employed to mimic brain deformation during catheter insertion [103] and to simulate periodical beating of the human heart [104].…”

Efficient Simulation of Volumetric Deformable Objects in Unity3D: GPU-Accelerated Position-Based Dynamics

“…The most widely used methods in computer graphics for simulating dynamic systems are force-based methods. Force-based approaches, such as the finite element method (FEM) and mass-spring systems, rely on computing the forces acting on a system and then integrating those forces to update the positions and velocities of the objects being simulated [29]. While these methods can produce highly accurate simulations, they can be computationally expensive, especially for large or complex systems.…”

Position-based dynamics simulator of vessel deformations for path planning in robotic endovascular catheterization

“…In [47], a device controller is developed that mimics a standard catheter handle, has a vibrotactile feedback, and is easy-to-use by cardiologists. However, joystick controllers with vibrotactile feedback are relatively easy to use and low in cost [14]. We will carry on long-term-following experiments to investigate a proper controller and its training effectiveness.…”

“…Compared with the first two methods, PBD is more suitable for real-time simulations because it does not need a complex mesh generation [11,12,13]. Although PBD is not as accurate as other methods, its high efficiency and close match to real deformations have been reported [14,15]. However, PBD parameters do not have physical meanings, and thus they should be properly tuned.…”