Logo
ScienceStack
Table of Contents
Fetching ...
Sign In

Interactive Surgical Liver Phantom for Cholecystectomy Training

Alexander Schuessler, Rayan Younis, Jamie Paik, Martin Wagner, Franziska Mathis-Ullrich, Christian Kunz

TL;DR

The paper tackles the need for safe, interactive training environments for robot-assisted cholecystectomy by introducing an interactive liver phantom with a latex gallbladder that supports realistic retraction and dissection. It combines a three-part tissue-mimicking phantom with a non-linear force representation, validated against an ex-vivo porcine liver, and demonstrates telemanipulated retraction experiments using a Franka Panda robot. Key contributions include the phantom design, a non-linear $F(x)=a x^2 + b x + c$ force profile (with $c=0$) for gallbladder retraction, and experimental validation showing comparable force-displacement behavior to real tissue, albeit with higher phantom peak forces ($F_{tmax,p}=9.97$ N) than ex-vivo tissue ($F_{tmax,ex}=2.06$ N). The work supports closer alignment between dry-lab and wet-lab training and enables potential sim-to-real reinforcement learning for robotic cholecystectomy applications, aiding safer and more effective surgical skill development. $F(x)=a x^2 + b x + c$ with $c=0$, and $F_{norm}(x)= \frac{F(x)}{F_{tmax}}$, are used to characterize retraction forces, providing a concrete basis for comparing phantom and real tissue behavior.

Abstract

Training and prototype development in robot-assisted surgery requires appropriate and safe environments for the execution of surgical procedures. Current dry lab laparoscopy phantoms often lack the ability to mimic complex, interactive surgical tasks. This work presents an interactive surgical phantom for the cholecystectomy. The phantom enables the removal of the gallbladder during cholecystectomy by allowing manipulations and cutting interactions with the synthetic tissue. The force-displacement behavior of the gallbladder is modelled based on retraction demonstrations. The force model is compared to the force model of ex-vivo porcine gallbladders and evaluated on its ability to estimate retraction forces.

Interactive Surgical Liver Phantom for Cholecystectomy Training

TL;DR

The paper tackles the need for safe, interactive training environments for robot-assisted cholecystectomy by introducing an interactive liver phantom with a latex gallbladder that supports realistic retraction and dissection. It combines a three-part tissue-mimicking phantom with a non-linear force representation, validated against an ex-vivo porcine liver, and demonstrates telemanipulated retraction experiments using a Franka Panda robot. Key contributions include the phantom design, a non-linear force profile (with ) for gallbladder retraction, and experimental validation showing comparable force-displacement behavior to real tissue, albeit with higher phantom peak forces ( N) than ex-vivo tissue ( N). The work supports closer alignment between dry-lab and wet-lab training and enables potential sim-to-real reinforcement learning for robotic cholecystectomy applications, aiding safer and more effective surgical skill development. with , and , are used to characterize retraction forces, providing a concrete basis for comparing phantom and real tissue behavior.

Abstract

Training and prototype development in robot-assisted surgery requires appropriate and safe environments for the execution of surgical procedures. Current dry lab laparoscopy phantoms often lack the ability to mimic complex, interactive surgical tasks. This work presents an interactive surgical phantom for the cholecystectomy. The phantom enables the removal of the gallbladder during cholecystectomy by allowing manipulations and cutting interactions with the synthetic tissue. The force-displacement behavior of the gallbladder is modelled based on retraction demonstrations. The force model is compared to the force model of ex-vivo porcine gallbladders and evaluated on its ability to estimate retraction forces.
Paper Structure (8 sections, 2 equations, 4 figures)

This paper contains 8 sections, 2 equations, 4 figures.

Table of Contents

  1. Introduction
  2. Materials & Methods
  3. Phantom Design
  4. Manufacturing Process
  5. Force Model & Experimental Validation
  6. Results
  7. Discussion
  8. Conclusion

Figures (4)

  • Figure 1: Phantom: Overview of the interactive phantom during a removal procedure. The surgical gripper for grasping the gallbladder and the dissecting instrument for the removal of the gallbladder are visible.
  • Figure 2: Ex-vivo porcine liver: Overview of an ex-vivo porcine liver during cholecystectomy.
  • Figure 3: Manufacturing process: The multi-step manufacturing process of the interactive phantom from manufacturing the molds and single parts to assembling the complete phantom.
  • Figure 4: Non-linear force model: Normalized force-displacement diagram with raw data points from six retraction demonstrations and force model for phantom and ex-vivo porcine liver.