Abstract
During needle insertion procedures, the insertion of the needle is accompanied by tissue fracture, which is the result of needle tissue interactions. The tissue fracture toughness is an important parameter to describe the resistance of tissue to crack generation, as well as to quantify the energy absorbed by the tissue during crack propagation. Fracture toughness can be affected by many factors, such as needle insertion speed, needle tip bevel angel and tissue Young’s modulus. However, existing studies on fracture toughness estimation did not consider the effect of Young’s modulus. In this paper the influence of three major factors on fracture toughness, specifically, insertion velocity, needle diameter and tissue Young’s modulus, are systematically studied. testbed is constructed, and the experiments are designed using polyvinyl alcohol tissue phantom with different insertion velocity, needle diameter and Young’s modulus. Experiments results show that the fracture toughness is positive proportional to insertion velocity, and Young’s modulus, and negative proportional to needle diameter. In addition, the sensitivity analysis shows that the effect of Young’s modulus to fracture toughness is less than other influencing factors.
