Background: Ultrasound can visualize significant portions of the upper and lower esophagus; it is without any instrumental interference in real conditions and displays events in motion.
Purpose: To study the events that occur during swallowing and gastroesophageal reflux.
Patients and methods: Group 1 comprised 25 patients with retrosternal complaints, selected for esophageal surface ultrasonography for endoscopic signs of esophagitis. Group 2 comprised 25 patients who underwent initial transabdominal ultrasonography. For 3 to 6 h before ultrasonography, nothing was given by mouth to the 50 patients labelled as having gastroesophageal reflux disease (GERD). Ultrasonography was then performed for 15 to 20 mins after drinking one mouthful of water or tea, or swallowing some saliva to provoke reflux. The events were recorded on videotape rolls. Endoscopy was carried out in all 50 cases; in 46 cases (21 and 25 from groups 1 and 2, respectively), gastric acidity and bacteriology were subsequently examined (test meal). Manometry and pH were not measured to avoid provocation of reflux by the instruments. Thirty patients without any esophageal complaints or signs of esophagitis (though suffering from gastric and duodenal diseases) were designated as the control group (group 3). The available results were compared.
Results: In 32 of 46 patients diagnosed with GERD (69.5% in groups 1 and 2), a special kind of reflux was observed by ultrasonography: a slow, trickling reflux of the gastric content was seen, mostly after swallowing. A fast clearance followed four to six episodes of the trickling reflux, only after an interval of 0.5 to 2 mins. Only fast refluxes and immediate clearance were observed in the control group.
Conclusions: The observations above may indicate a special form of gastroesophageal reflux, namely, a slow, trickling form of it. It can be responsible for the development of GERD. Fast reflux and immediate clearance are common; however, this special trickling form was observed only in GERD patients. This may explain a number of often contradictory measurements and can make the effect of cisapride more understandable. A test meal is always necessary to distinguish a bilious reflux from an acidic one, because only the latter may require aggressive antacidic treatment.