Pseudo-three-dimensional reconstruction of ultrasonic images of the tongue

The purpose of the present investigation was to develop a method for the three-dimensional reconstruction of the surface of the tongue using serial ultrasonic images gathered during the production of the sustained fricative /s/. Using a phased linear array ultrasonic monitoring system, transducer position, subject position, and ultrasonic scan data were recorded simultaneously on composite video for off-line analysis. Reconstruction of a series of ultrasound images was completed using a microcomputer programmed to transform the ultrasonic image contours into three-dimensional space. Additional transformations converting the three-dimensional tongue contours into two dimensions for screen plotting were also developed. Results are discussed in light of previously reported models of the tongue surface.