Effect of tongue-hold swallow on pharyngeal cavity: kinematic analysis using 320-row area detector CT

doi.org/10.11336/jjcrs.11.35 Jpn J Compr Rehabil Sci Vol 11, 2020 ©Kaifukuki Rehabilitation Ward Association 2020 ABSTRACT Aihara K, Inamoto Y, Aoyagi Y, Shibata S, Kagaya H, Sato Y, Kobayashi M, Saitoh E. Effect of tongue-hold swallow on pharyngeal cavity: kinematic analysis using 320-row area detector CT. Jpn J Compr Rehabil Sci 2020; 11: 35-42. Purpose: This study analyzed the effect of the tonguehold swallow (THS) on the pharyngeal cavity during swallowing three-dimensionally using 320-row area detector computed tomography (320-ADCT). We hypothesized a greater decrease in pharyngeal volume with the THS than with the saliva swallow (SS); that is, the pharyngeal cavity would be more constricted with the THS. Methods: The THS and SS were examined using 320ADCT in six speech language pathologists (22-29 years old). Pharyngeal volume, hyolaryngeal displacement, and cross-sectional area of the upper esophageal sphincter (UES) were measured frame-by-frame and compared between the two swallows. Results: Although some participants showed smaller pharyngeal volume with the THS than hypothesized, others showed larger pharyngeal volume. With the THS, the hyoid bone was positioned significantly higher at swallow onset, the hyoid and larynx were significantly higher at maximum superior displacement, and the cross-sectional area of the UES was significantly larger. Discussion: No constant effect of the THS on pharyngeal volume was found. The THS may influence hyolaryngeal elevation and UES opening. Further study is necessary to consider the methodology of the THS, such as tongue protrusion length.