Bevel-Tip Needle Deflection Modeling, Simulation, and Validation in Multi-Layer Tissues (2311.18075v1)

Abstract: Percutaneous needle insertions are commonly performed for diagnostic and therapeutic purposes as an effective alternative to more invasive surgical procedures. However, the outcome of needle-based approaches relies heavily on the accuracy of needle placement, which remains a challenge even with robot assistance and medical imaging guidance due to needle deflection caused by contact with soft tissues. In this paper, we present a novel mechanics-based 2D bevel-tip needle model that can account for the effect of nonlinear strain-dependent behavior of biological soft tissues under compression. Real-time finite element simulation allows multiple control inputs along the length of the needle with full three-degree-of-freedom (DOF) planar needle motions. Cross-validation studies using custom-designed multi-layer tissue phantoms as well as heterogeneous chicken breast tissues result in less than 1mm in-plane errors for insertions reaching depths of up to 61 mm, demonstrating the validity and generalizability of the proposed method.

• The paper introduces a 2D mechanics-based model that captures nonlinear, strain-dependent behaviors of soft tissues.
• The paper employs real-time finite element simulation to steer the needle with three degrees of freedom in various tissue layers.
• The paper validates its model using multi-layer phantoms and real tissues, achieving in-plane errors of less than 1mm over 61mm insertion depths.

Introduction

Percutaneous needle-based procedures, such as biopsies and injections, play a crucial role in modern medical diagnostics and treatments. The accuracy of these procedures is paramount as it directly impacts clinical outcomes. One of the significant challenges in performing precise needle insertions is needle deflection that occurs due to interactions with soft tissue. This paper presents a novel approach to predicting and accounting for needle deflection during insertions into multi-layer soft tissues.

Modeling Bevel-Tip Needle Interactions with Soft Tissues

The cornerstone of the research is a mechanics-based model for a 2D bevel-tip needle which accounts for the nonlinear and strain-dependent behavior of soft tissues, typically not captured in simpler models. In the proposed framework, real-time finite element simulation is employed to facilitate control inputs along the needle's length, offering full three degrees of freedom for planar motions. This flexibility in control allows the simulation of varying clinical scenarios, including multi-layer tissue penetration that mimics real biomedical settings.

Simulation and Experimental Validation

To validate the model, researchers conducted cross-validation studies using custom-designed multi-layer soft tissue phantoms and real chicken breast tissues. The simulation's outputs were compared to needle insertion depths of up to 61 mm, with the results exhibiting in-plane errors of less than 1mm, underscoring both the model's validity and its general applicability across different soft tissue scenarios.

Moving Forward

The success of this modeling approach in reflecting the real-world behavior of needles in soft tissues illustrates its potential effectiveness in enhancing the accuracy of needle-based medical procedures—potentially leading to improved patient outcomes in clinical settings. Future developments could see the extension of this model to three-dimensional applications and the integration of real-time feedback mechanisms, such as intraoperative imaging, which would further solidify its clinical utility in precision-focused medical interventions.