Elasticity measurement of Biological tissue using a Probe Type Instrument
In this paper, the elastic properties of chicken and bovine livers were measured using a probe type instrument. The design of the instrument and the method for calculation the parameters were presented, followed by the experimental validation of the method using artificial material. The validated method was then used to measure the chicken and bovine livers. Good agreements in curve fitting were obtained using the proposed method. Experimental results showed that the chicken liver demonstrated stronger nonlinear behaviors comparing to the bovine liver. I. I NTRODUCTION Surgical simulation provides an good option for surgical training and optimal surgical planning before actual surgery. To this end, accurate computer model of human organs and tissues are required, which further requires accurate physical properties of these tissues. However, measuring such properties in vivo is a very challenging task due to the complex internal environment and limited space inside body. To take this challenge, in this research, a probe type device was proposed towards portable measuring system for calibrating tissue properties. II. M ETHOD Most of human organs and tissues are supposed to be incompressible and the Poisson's ratio g was considered to be close to 0.5. In this work, we set Poisson's ratio g as a constant of 0.49 and we are focusing on the calculation of elasticity, i.e. the Young's modulusE. According to Hertz contact mechanics, the contact forceF between a sphere and a flat elastic surface is given by: F 4 3 E 1 g2 R 1 2 d 3 2 (1) whereR denotes the radius of the sphere and d enotes the indentation depth. The relationship was further extended to Eq.