TRANSAXIAL COMPRESSION TECHNIQUE FOR SOUND VELOCITY ESTIMATION

摘要

An improved ultrasonic pulse-echo method and apparatus that has particular application in estimating sound velocity in organic tissue is disclosed. The method employs a standard transducer or transducer containing device which is translated transaxially, thereby compressing or displacing a proximal region of a target body in small known increments. At each increment, a pulse is emitted and an echo sequence (A-line) is acquired from regions within the target along the sonic travel path or beam of the transducer. Segments of the echo sequence corresponding to a distal region within the target are selected as a reference to estimate the incremental change in echo arrival time. A plot of these arrival time estimates versus the target compression depth is then generated and a least squares linear fit is made. The slope of the linear fit is c-1, where c is an estimate of the speed of sound in the target.