MANOMETRIC ASYMMETRY OF THE LOWER ESOPHAGEAL SPHINCTER

Abstract

Manometric pressure profile of the lower esophageal sphincter (LES) was studied at 3 different points at the same level in 10 adult candidates from 18 to 25 years of age and 6 children from 3 months to 5 years of age who clinically have no abnormality in the upper gastrointestinal tract. This esophageal tube used for adult is Esophageal Motility Tube produced by Sherwood Company which has 3 side holes circularly located at every 120 degree at 5 cm proximal to the tip.For children was used our original tube which is a smaller 3-lumen tube with 3 side holes circulerly located at every 120 degree at 3 cm proximal to the tip.These 3 holes were always kept to face to the anterior (O o'clock), right posterolateral (4 O'clock) and left posterolateral (8 o'clock) in the esophagus, respectively. And pressure profile of LES was measured by a rapid pull through technique.In the normal adults, high pressure zone (HPZ) which is a manometric representation of LES was observed to have 25.1cm H2O at 0°, 16.1cm H2O at 4° and 28.4cm H2O at 8° in average in tone, and 34.5 mm at 0°, 40.4mm at 4° and 27.7mm at 8° in average in length. In normal children an average tone of HPZ was 13.9cm H2O at 0°, 8.4cm H2O at 4° and 17.4cm H2O at 8°, and length of HPZ was 16.1mm at 0°, 20.3mm at 4° and 11.6mm at 8°. These findings indicate that there is an asymmetry in manometric profile of normal LES both in adults and children, with the highest tone at 8° and the lowest at 4°, and the longest length at 4° and the shortest at 8°.In contrast with manometric profile of normal LES, pathological LES was assessed by the same technique in a patient with achalasia of the esophagus, a patient with systemic sclerodema, two patients with hiatal hernia, a patient with traumatic diaphragmatic hernia and a patient with Barrett esophagus. In any one of the above pathological conditions of LES, asymmetry in pressure profile was not observed.The effect of gastrin on LES was further investigated in the same 10 adult candidates by the same technique. Only a slight increase in the tone was observed in 3 directions about 2 minutes after intravenous administration of tetragastrin (0.5 γ/kg).This paper summarized our study on a manometric asymmetry of normal LES in contrast with manometric changes in various diseases that have pathological LES. Further study on these manometric charactaristics and their combinations might us a great advance in clarification of anti-reflux mechanism of LES.