Minimally Invasive Flexible Needle Manipulation Based on Finite Element Simulation and Cross Entropy Method

TL;DR

A novel approach for minimally invasive flexible needle manipulations is presented by pairing a real-time finite element simulator with the cross-entropy method and it is shown how electromagnetic (EM) tracking can be readily incorporated into the framework to provide controller feedback.

Abstract

We present a novel approach for minimally invasive flexible needle manipulations by pairing a real-time finite element simulator with the cross-entropy method. Additionally, we demonstrate how a kinematic-driven bang-bang controller can complement the control framework for better tracking performance. We show how electromagnetic (EM) tracking can be readily incorporated into the framework to provide controller feedback. Tissue phantom experiment with EM tracking shows the average targeting error is $0.16 \pm 0.29mm$.

Figures (7)

• Figure 1: Model schematic generated by the simulator. Three actions, $\delta b_x$, $\delta g_y$, and $flip$ correspond to needle insertion, needle guide translation, and bevel direction change, respectively. Needle guide is separated from skin entry point by distance $G$.
• Figure 2: Insertion plans returned by CE using manipulation and steering strategies. The manipulation strategy attempts to find a non-zero insertion angle such that needle bevel can be effectively used to steer towards target, while a pure steering strategy relies only on changing of bevel direction to achieve steering.
• Figure 3: Comparison between different feedback modalities: (a) EM tracking, (b) medical imaging, and (c) fiber Bragg grating with the proposed FE-based framework.
• Figure 4: Indicator value correlates measurement error in a piecewise linear fashion. Indicator values beyond 0.3 are not shown to better visualize data in the ideal environment.
• Figure 5: Tissue phantom experiment setup. Needle driver generates $\delta b_x$ and $flip$, and linear stage (not shown) generates needle guide $\delta g_y$ attached to the aluminum profile. Three EM reference markers are used to monitor field distortion.