Investigation of Needle-tissue Friction Force and Geometric modeling of Hypodermic Needle

Open Access
Author:
Abdullah, Arif Md
Graduate Program:
Mechanical Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
April 01, 2013
Committee Members:
  • Jason Zachary Moore, Thesis Advisor
Keywords:
  • Needle-Tissue Friction
  • Brachytherapy
  • Surface Texture
  • Hypodermic Needle
  • Needle Modeling
  • Patient Pain
  • Needle Tip Volume
Abstract:
This thesis investigates how surface roughness and insertion speed affects the frictional force at the needle-tissue interface and forms an analytical model for defining the tip geometry of a three bevel hypodermic needle. High frictional forces between the needle surface and tissue create high insertion forces that reduce needle positioning accuracy in procedures such as brachytherapy radiation treatment and needle biopsy. Failure to accurately place needles inside the body reduces the efficacy of the procedure and can lower the patient’s quality of life. The first part of this thesis experimentally investigates the frictional force and needle positioning accuracy at the needle-tissue interface. It was found that, rougher surface texturing of the needles generally reduced the friction forces and higher insertion speeds resulted in increased frictional forces. Texturing was also shown to improve the targeting accuracy of the needles across all the speeds. Analytical models for defining needle tip geometry can play important roles in needle performance evaluation and comparison by providing insight about different needle tip features. These models can also be applied to calculate the needle tip volume for a given insertion depth. Knowledge about how the needle tip volume changes with increasing insertion depth is important as needles with thinner profile near the tip have been reported to reduce patients’ pain. Minimizing needle insertion pain can improve patient adherence to diabetes treatments. The second part of this thesis formulates an analytical model for defining the geometry of a three-bevel hypodermic needle and uses the model to calculate the needle volume at varying insertion depths.