BACKGROUND: Esophageal adenocarcinoma and dysplasia in patients with Barrett's esophagus are seen after surgical treatment of GERD (fundoplication).Esophageal pH monitoring shows no evidence of acidity, suggesting distal reflux to the conventional catheter positioning. AIM: To develop methodology for assessing ultra-distal reflux (1 cm above the top edge of the lower esophageal sphincter). METHOD: Were selected 11 patients with Barrett's esophagus previously submitted to Nissen fundoplication, without reflux symptoms and with endoscopy and contrasted study of esophagus without signs of relapse. Esophageal manometry was used to evaluate the location and length of the lower sphincter of the esophagus (LES). After that, esophageal pH monitoring with four channels was done: channel A at 5 cm above the top edge of the LES; channel B at 1 cm above; channel C, intra-sphincteric; channel D, intragastric. The DeMeester score was assessed on channel A. The number of episodes of acid reflux, the number of episodes of prolonged reflux and fraction of time pH<4.0 were compared on channels A and B. The fraction of time pH<4.0 was compared on channels B and C. The fraction of time with pH<4.0 above 50% on channel D was used as parameter of no proximal migration of the catheter. RESULTS: Significant increase in the number of reflux episodes and fraction of time pH<4.0 in channel B in relation to channel A. Reduced fraction of time pH<4.0 in channel B compared to channel C was seen. Two cases of esophageal adenocarcinoma were diagnosed in the group. CONCLUSIONS: The zone 1 cm above the top edge of the LES is more exposed to acidity than the one 5 cm above, although at reduced levels. The region 1 cm above the top edge of the LES is less exposed to acidity than the intrasphincteric zone, demonstrating efficacy of fundoplication.
Gastroesophageal reflux; Barrett esophagus; Esophageal pH monitoring; Fundoplication
