A guide to analysing tongue motion from ultrasound images

This paper is meant to be an introduction to and general reference for ultrasound imaging for new and moderately experienced users of the instrument. The paper consists of eight sections. The first explains how ultrasound works, including beam properties, scan types and machine features. The second section discusses image quality, including the interpretation of anatomical features and artefacts seen in the image. The third section discusses the validity of the data collection procedures, including the effects of stabilizing the transducer and head position, and discusses some methods for stabilization. Section four discusses validation of the ultrasound and stabilization systems. The fifth section presents a sample recording set-up, supplemental information, and normalization strategies for sessions and subjects. In section six are methods of extracting contours from ultrasound images, displaying them, and analysing them. The seventh section considers the tracking of pellets on the tongue surface and the differences between tracking tissue points and continuous surfaces. The last section presents methods, challenges and results of 3D, computerized reconstruction of tongue surfaces. An outline of the paper can be found in Appendix I.