Noninvasive measurement of temperature distribution in pseudo body with tissue distribution using ultrasonic CT

Abstract

The purpose of this study is to develop a noninvasive method to obtain temperature distribution in tissues with ultrasonic CT system, using relation between sonic velocity and temperature. In this CT system, successive approximation method based on projection onto convex set method (POCS) and smooth processing is used to reconstruct sonic velocity distribution from projection data (sinogram) of wave propagation time through the tissue. In this study, CT reconstruction from sinogram obtained from the objects composed by multiple tissues was performed experimentally, and following results were obtained. (1) Reconstruction by AART with POCS and smooth processing showed better distributions compared with those by only AART. (2) Temperature distribution by AART with POCS and smooth processing was similar to that measured by thermocouples. (3) Error of shape information showed the adverse effect to reconstruct higher temperature near the center of tissue.