Objective: The present study is intended to compare swallowing characteristics between normal controls and patients with dysphagia through quantification of the pharyngeal movement. Background: The existing diagnoses of swallowing have been qualitativ...
Objective: The present study is intended to compare swallowing characteristics between normal controls and patients with dysphagia through quantification of the pharyngeal movement. Background: The existing diagnoses of swallowing have been qualitatively conducted by a clinician referring to results of the VideoFluorocopic Swallowing Study (VFSS) or the Fiberoptic Endoscopic Evaluation of Swallowing (FEES); therefore, a quantitative methodology for assessment of the swallowing is required to diagnose dysphagia more accurately. Method: A three-step approach was applied in the study: (1) development of a swallowing measurement device consisting of an ultrasonic Doppler sensor to measure the pharyngeal movement, (2) establishment of five swallowing quantification measures (peak amplitude, duration, number of peaks, peak interval, and impulse of swallowing) by a swallowing signal preprocessing, (3) evaluation of the swallowing in 120 normal controls and 36 dysphagic patients by three-step protocol (S1. informed consent, S2. exercise, S3. swallowing session; type and volume: dry saliva, thin liquid 1, 3, 9 ml, and thick liquid 1, 3, 9 ml). Results: Swallowing signals of normal controls and dysphagic patients classified into 2 types (short-single: 39%; short-double: 43%) and 3 types (short-double: 58%; long-double: 33%; long-multiple: 9%), respectively. Dysphagic patients had difficulties in swallowing of 9 ml regardless of swallowing type. Highest peak amplitude, duration, number of peaks, average peak interval, and impulse of dysphagic patients were 1.3 times higher (t = 4.31, p < .001), 3 times longer (t = -11.15, p < .001), 2 times more (t = -6.73, p < .001), 2 times longer (t = -9.23, p < .001), and 1.3 times lower (t = 8.94, p < .001) than those of normal controls, respectively. Application: The swallowing characteristics of dysphagic patients can be applied to develop a diagnostic model which can evaluate quantitatively the existence and severity for dysphagia.