ABSTRACT
BACKGROUND: Little is known about the role of muscularis mucosa at the gastroesophageal junction (GEJ). AIM: To evaluate the movement of the mucosa/muscularis-mucosa/submucosa (MMS) at the GEJ in normal subjects and in patients with gastroesophageal reflux disease (GERD). METHODS: Gastroesophageal junctions of 20 non-GERD subjects and 10 patients with GERD were evaluated during 5 mL swallows using two methods: in high-resolution endoluminal ultrasound and manometry, the change in the GEJ luminal pressures and cross-sectional area of esophageal wall layers were measured; in abdominal ultrasound, the MMS movement at the GEJ was analyzed. RESULTS: Endoluminal ultrasound: In the non-GERD subjects, the gastric MMS moved rostrally into the distal esophagus at 2.17 s after the bolus first reached the GEJ. In GERD patients, the gastric MMS did not move rostrally into the distal esophagus. The maximum change in cross-sectional area of gastroesophageal MMS in non-GERD subjects and in GERD patients was 289 % and 183%, respectively. Abdominal ultrasound: In non-GERD subjects, the gastric MMS starts to move rostrally significantly earlier and to a greater distance than muscularis propria (MP) after the initiation of the swallow (1.75 vs. 3.00 s) and (13.97 vs. 8.91 mm). In GERD patients, there is no significant difference in the movement of gastric MMS compared to MP (6.74 vs. 6.09 mm). The independent movement of the gastric MMS in GERD subjects was significantly less than in non-GERD subjects. CONCLUSION: In non-GERD subjects, the gastric MMS moves rostrally into the distal esophagus during deglutitive inhibition and forms a barrier. This movement of the MMS is defective in patients with GERD.