Validity and Reliability of a Noninvasive Device for Measuring Laryngeal Movement During Swallowing

Background Laryngeal movement plays a crucial role in the process of swallowing. Peak velocity of laryngeal movement has been shown to be useful in predicting laryngeal penetration and aspiration. There is a growing need to accurately capture and quantify laryngeal movements during swallowing. Objective This research comprises two investigations that aim to verify and establish the reliability of a noninvasive device designed to measure laryngeal movement during swallowing. Methods In Step 1, one healthy male in his 30s underwent simultaneous videofluoroscopy (VF) examination and noninvasive device measurement. VF videos were employed to generate laryngeal movement curves using video analysis software. In Step 2, 19 healthy young adult men (20-39 years old) and 19 healthy older men (60-79 years old) were instructed to perform five saliva swallows each, with a noninvasive device placed against their necks. Results In Step 1, the comparison of laryngeal movement curves between VF and the noninvasive device exhibited almost perfect agreement for upward-downward movement, with less agreement noted for anterior-posterior movement. In Step 2, the reliability of the measurements of peak velocity and distance traveled in Nodomiru showed moderate to high reliability for single measurements (intraclass correlation coefficient (ICC) (1,1) = 0.598-0.855) and high reliability for the average of five measurements (ICC (1,5) = 0.694-0.967). Conclusions The results of this study suggest that it is possible to measure the upward-downward movement of the larynx in healthy men using a noninvasive device.