The effects of bolus flow on vertical pharyngeal pressure measurement in the pharyngoesophageal segment: clinical significance.

Measurement of pressures in the pharyngeal esophageal segment (P-E segment) is complicated by the vertical motion and by the rapidly changing pressures in the segment. The sensors move superiorly and inferiorly with respect to the P-E segment during the swallow. This study examines the validity of manofluorographic measurements taken in the P-E segment by using a catheter with sensors spaced at 1 cm intervals. Seven normal volunteers were tested. Measurements were similar using one sensor and using an average of five sensors. During the time of bolus passage, the P-E segment is open and the bolus itself equalizes pressures measured within the bolus.