Session: 07-04-01: Biomaterials and Tissue: Modelling, Fabrication and Characterization

Paper Number: 192322

Force Response of Percutaneous Needle Insertion in Viscoelastic Soft Tissue: Experimental and Numerical Analysis 

Percutaneous needle insertion is widely used in minimally invasive medical procedures such as biopsy, ablation, drug delivery, and other image-guided interventions. During these procedures, the force generated as the needle moves through soft tissue can affect targeting accuracy, tissue deformation, needle path stability, and procedural safety. A better understanding of how material stiffness and insertion speed influence the force response is important for improving needle placement, developing robotic needle-insertion systems, and creating more realistic surgical training models. In this study, needle insertion into viscoelastic tissue-mimicking gels was investigated using experimental measurements and numerical simulation. An 18G stainless-steel hollow needle was inserted into two groups of tissue-mimicking gels with different stiffness levels. The softer gel had a Young’s modulus of 13.32 ± 1.94 kPa, while the stiffer gel had a Young’s modulus of 25.19 ± 4.68 kPa. The needle was inserted to a depth of 60 mm at three constant insertion speeds of 2.5, 5, and 10 mm/s. During each test, the force between the needle and the gel was measured during both insertion and extraction. The force response was evaluated using several indicators, including peak insertion force, insertion slope, mean insertion force, mean extraction force, peak extraction force, and hysteresis. These indicators were used to compare the effect of gel stiffness and needle insertion speed on the overall needle–gel interaction. The experimental results showed that gel stiffness had a clear effect on the force response. At all insertion speeds, higher forces were measured as the needle moved into and out of the stiffer gel compared with the softer gel. The stiffer gel also showed greater hysteresis, indicating higher energy loss as the needle was inserted into and extracted from the gel. In addition, insertion speed affected the measured force response. As the needle moved into the gel at higher speeds, most force indicators increased, showing clear rate-dependent behavior. This behavior is related to the viscoelastic properties of the gel, where the material response depends on the rate of deformation. An Arbitrary Lagrangian–Eulerian model was developed in LS-DYNA to simulate the needle moving through the gel and to predict the insertion-force response. Four numerical cases were compared with the experimental results to evaluate the effects of gel stiffness and needle insertion speed. The model captured the general trend of increasing insertion force as the needle moved deeper into the gel. The errors in the predicted peak insertion forces ranged from 0.4% to 13.1%. Overall, the experimental and numerical results showed that both gel stiffness and needle insertion speed strongly affected the force generated during needle insertion and extraction. The developed model provides a useful approach for predicting the force response during needle insertion into viscoelastic soft materials.

 

Presenting Author: Parsaoran Hutapea Temple University

Presenting Author Biography: Dr. Parsaoran Hutapea is a Professor in the Department of Mechanical Engineering. He received his BS, MS, and PhD all in Aerospace Engineering from North Carolina State University, Raleigh, North Carolina. He was a Postdoctoral Fellow in the Department of Mechanical Engineering and Mechanics at Lehigh University, Bethlehem, Pennsylvania. Dr. Hutapea is a Fellow of the American Society of Mechanical Engineers.

Authors:

Hamidreza Ghasempoor Temple University
Parsaoran Hutapea Temple University