Temporal and Sequential Analysis of the Pharyngeal Phase of Swallowing in Poststroke Patients

The purpose of this study was to conduct a quantitative analysis of the temporal and sequential events of the pharyngeal phase of swallowing in 45 poststroke patients who presented or did not present with supraglottic penetration and/or laryngotracheal aspiration and to compare the groups with each other and to a group of 46 patients with normal swallowing. All individuals were assessed by videofluoroscopy and the temporal and sequential measures for the swallowing of 3 mL and 5 mL of thickened liquid, 3 mL of liquid, and 3 mL and 5 mL of pasty were obtained by analyzing the recorded exams on Virtual Dub software. The following events were measured: time of maximal displacement and sustaining of the hyoid and larynx, duration of velopharyngeal sphincter (VS) and supraglottic closure, total inversion time of the epiglottis, duration of pharyngeal constriction, and duration of upper esophageal sphincter (UES) opening. For the analysis of the temporal sequence, the initial time of larynx and hyoid elevation, VS closure, epiglottic inversion, supraglottic closure, pharyngeal constriction, and opening of the UES were obtained. For 5 mL of thickened liquid, the maximum hyoid elevation time was greater for patients with normal swallowing and the time the supraglottis remained closed was higher in the aspirators group. The time of pharyngeal constriction during swallowing of 3 mL of thickened liquid was lower in the aspirators group. During the swallowing of 3 mL of thin liquid, it was observed that in the aspirators group, the larynx took longer to reach its maximum elevation and the epiglottis took longer to complete its total inversion. The analysis of the temporal sequence showed that patients in the aspirators group presented greater disorganization with significant alteration of the time interval between the events.