Videomanometric aspects of pharyngeal constrictor activity.

Pressure changes were registered with videomanometry (simultaneous manometry and barium swallow) in the pharynx and in the pharyngoesophageal segment (PES) during swallowing. A considerable longitudinal asymmetry was found. Peak pressure was highest in the PES, lower in the inferior constrictor area, and lowest at the level of the tongue base. The rate of pressure rise was highest at the level of the PES. The speed of propagation of the contraction wave was 13 (+/- 2) cm/sec. There was no correlation between the measured variables (i.e., peak pressure, rate of pressure rise, and speed of contracting wave). Our findings can partly be explained by different mechanical constraints at different levels of the pharynx but may also reflect the organization of neural control of swallowing in the brainstem. Knowledge of transducer position and orientation is essential for the evaluation of pharyngeal pressure during swallowing. Such knowledge is best achieved by performing manometry simultaneously with fluoroscopy, i.e., videomanometry.