Evaluation of Pharyngeal Swallowing Elicited by Fluid Infusion Using Videoendoscopy in Dysphagia Patients

Evaluation of Swallowing Using 320-detector-row Multislice CT. Part II: Kinematic Analysis of Laryngeal Closure during Normal Swallowing

“…Swallowing is effective if laryngeal closure is accomplished before the bolus is transported to the distal pharynx to prevent aspiration [7]. We found, however, that neither the laryngeal vestibule nor the TVCs started to close, and the epiglottis was not inverted maximally in any volunteers except one when the contrast medium passed through the lateral food channels on either side of the laryngeal entrance.…”

“…They reported in their later work that the same phenomenon was observed in elderly subjects [12]. Meanwhile, Ohmae et al [6,7], using the same concurrent techniques, reported that TVC closure occurred after the onset of laryngeal elevation and achieved maximum closure during laryngeal elevation and when the UES opened. Van Daele et al [21], using concurrent EMG and videoendoscopy, stated that arytenoid adduction was induced first, laryngeal elevation followed, and TVCs closed during laryngeal elevation.…”

“…Laryngeal closure includes three distinct events: glottal closure, closure of the laryngeal vestibule, and downward tilting of the epiglottis [1][2][3][4]. Several studies have reported the sequence of these actions during swallowing relative to other oral and pharyngeal swallowing events such as hyoid movement and upper esophageal sphincter (UES) opening [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21]. Studies have shown that closure of the true vocal cords (TVCs) is synchronized with hyolaryngeal elevation [6,7,16,17,21], and epiglottic movement is the result of hyolaryngeal movement and tongue base retraction [5].…”

“…Several studies have reported the sequence of these actions during swallowing relative to other oral and pharyngeal swallowing events such as hyoid movement and upper esophageal sphincter (UES) opening [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21]. Studies have shown that closure of the true vocal cords (TVCs) is synchronized with hyolaryngeal elevation [6,7,16,17,21], and epiglottic movement is the result of hyolaryngeal movement and tongue base retraction [5]. However, the mechanisms of laryngeal closure are not fully understood, especially with respect to the temporal characteristics of the three components of swallowing and the temporal relationships with other swallowing events, mainly because of the inability to visualize all of these three components using any one technique.…”