Relationships between diaphragmatic hiatus and infra-diaphragmatic esophagus: a combined X-ray and manometry study.

The relationship between the diaphragmatic hiatus, the infra-diaphragmatic esophagus and a manometric tube were examined in 10 patients not suffering from hiatal hernia or gastroesophageal reflux. During surgery, two metal markers were attached to the diaphragmatic hiatus and two others were fixed at the vertex of the angle of His. X-ray examinations were taken during manometric recordings of the high pressure zone (HPZ) both at rest and during relaxation. Comparison between the radiographs showed that during swallowing the manometric tube did not move with respect to the vertebral bodies; contraction of the esophagus caused complete disappearance of the infra-diaphragmatic esophagus. It was also observed that during pressure drop in the HPZ (so-called lower esophageal sphincter relaxation), the manometric recording site is located below the vertex of the angle of His, i.e. in the gastric cavity. These findings provide the basis for a hypothesis to explain the passage of a solid bolus through the lower esophagus into the stomach.