MEASURING THE ELASTIC-MODULUS OF SMALL TISSUE SAMPLES

Independent measurements of the elastic modulus (Young' s modulus) of tissue are a necessary step in turning elasticity imaging into a clini cal tool. A system capable of measuring the elastic modulus of small t issue samples was developed. The system tolerates the constraints of b iological tissue, such as limited sample size less than or equal to 1. 5 cm(3)) and imperfections in sample geometry. A known deformation is applied to the tissue sample while simultaneously measuring the result ing force. These measurements are then converted to an elastic modulus , where the conversion uses prior calibration of the system with plast isol samples of known Young's modulus. Accurate measurements have been obtained from 10 to 80 kPa, covering a wide range of tissue modulus v alues. In addition, the performance of the system was further investig ated using finite element analysis. Finally, preliminary elasticity me asurements on canine kidney samples are presented and discussed. (C) 1 998 Dynamedia, Inc.