Wearable Band-Shaped Device and Detection Algorithm for Laryngeal Elevation in Mendelsohn Maneuver

Aspiration pneumonia is a serious condition in the elderly. To strengthen the muscles required for swallowing, patients can train using the Mendelsohn maneuver, wherein they maintain their larynx at the top of the laryngeal elevation during swallowing. This study describes a wearable device to detect the onset and offset times of the laryngeal elevation for a biofeedback system to support this training. The biofeedback system consists of a band-shaped device with stretchable strain sensors. The strain sensors measure the change of circumferential length of the neck. An algorithm detects the onset and offset times of the laryngeal elevation based on the absolute first-order difference of the measured data and distance between the measured data and template data by pattern matching. The algorithm detected the onset and offset times of 53 out of 54 data sets from elderly participants. Cluster analysis separated the data into two groups. For both groups, the mean absolute error of the interval time was within 1 s when compared with the time recorded by a speech-language-hearing therapist. We believe that this biofeedback system for the Mendelsohn maneuver tolerates the 1 s delay. The wearable device is soft, lightweight, and easy for a patient to use alone. The efficacy of the device for the strengthening of muscles must be verified in a clinical study.