Manometry of individual segments of the distal esophageal sphincter. Its relation to functional incompetence.

The major components of the lower esophageal sphincter, the pressure it exerts, its total length, and the length of sphincter affected by abdominal pressure are usually expressed as means of several recordings from different radial segments of the sphincter. In segmental manometry, the individual readings for these components in each segment, rather than the mean values, are analyzed. We used segmental manometry to study 50 normal volunteers and 200 patients with symptoms suggestive of gastroesophageal reflux. Of the latter, 100 had increased esophageal acid exposure and 100 did not. An increased number of defective segments was associated with a greater prevalence of increased esophageal acid exposure. Segmental analysis disclosed the same number (52) of defective sphincters (defined as sphincters with two or more defective segments) in the 100 patients with increased acid exposure as did standard analysis. However, the relationship between a defective lower esophageal sphincter and the number of reflux episodes was clearer when a defective sphincter was defined using standard analysis. Segmental analysis of the lower esophageal sphincter has no clear advantage over standard analysis.