Temporal sequence of swallow events during the oropharyngeal swallow

To (a) identify and characterize the temporal relation of selected structural movements during the oropharyngeal swallow across participants, (b) determine whether patterns of movement could be identified, and (c) determine whether the temporal relations were affected by aging and bolus characteristics.

Retrospective analysis of videofluoroscopic swallows of 100 normal participants (age range=22-92 years) was conducted. Two swallows each of 3-ml and 10-ml liquids and a 1-3-ml paste bolus were analyzed. The onset of a number of structural movements and bolus arrival points were compared against a single reference event: onset of upper esophageal sphincter (UES) opening.

Normal participants demonstrated predominant sequences in pharyngeal movement patterns with some variability. The use of voluntary swallow maneuvers by these normal participants accounted for some degree of this variability. Volume, consistency, and age all affected the temporal relation between onset of specific motor events relative to the onset of UES opening. Increasing bolus volume was associated with a shorter temporal difference between UES opening and onset of other pharyngeal movements. In contrast, a thicker bolus was associated with longer temporal differences. Younger participants generally demonstrated shorter temporal differences between events than did older participants.

Temporal relations between structural movements are not fixed but can be systematically affected by bolus characteristics and age.