Effects of head rotation on pharyngeal function during normal swallow.

This study quantified the effects of head rotation on pharyngeal swallowing in healthy subjects. Videofluoroscopic and oropharyngeal manometric examinations of pharyngeal swallowing were performed on seven volunteers with the head in neutral and rotated positions. Videofluoroscopic study revealed that head rotation swallow causes the bolus to lateralize away from the direction of head rotation. Pharyngeal manometric study indicated that the pharyngeal peak pressures toward the side of head rotation were significantly increased, whereas the pharyngeal pressures opposite the side of head rotation were not affected. Head rotation swallow produced a significant fall in upper esophageal sphincter (UES) resting pressure and a delay in UES closing. We concluded that the head rotation swallow in normal subjects not only alters the bolus pathway, but also has a useful effect on both pharyngeal clearance and UES dynamics.