Mk. Kern et al., KINEMATIC AND DYNAMIC CHARACTERISTICS OF SOLID PELLET MOVEMENT DURINGTHE PHARYNGEAL PHASE OF SWALLOWING, The Annals of otology, rhinology & laryngology, 105(9), 1996, pp. 716-723
Information on solid particle movement through the pharynx, in additio
n to its physiologic importance, has relevance to the swallowing of me
dications in pill form. The purpose of this study was to determine the
kinematics of a solid particle during the oral-pharyngeal phase of sw
allowing. We used a concurrent manometric-videofluoroscopic technique
and identified two distinct zones of increasing bolus velocity, one at
the tongue base and the other at the pharyngo-upper esophageal sphinc
ter (UES) region. Velocity de creased significantly (p <.05), to 9.0+/
-1.0 cm/s, while the bolus traversed the area located between the tip
of the horizontal epiglottis and the pharyngeal wall. The velocity of
the liquid barium bolus head was similar to that of the solid barium p
ellet. The average bolus tail velocity was relatively constant. The ac
celeration of the barium pellet was temporally associated with develop
ment of an incrementally decreasing pressure distal to the location of
the pellet in the hypopharynx and across the UES. In conclusion, the
kinematics of a solid particle are similar to those of the head of a l
iquid bolus, but both are different from bolus tail kinematics. During
the pharyngeal phase of swallowing, the area located ahead of the bol
us exhibits an incrementally decreasing pressure, caudally. This may f
acilitate bolus transport and contribute to airway protection.