Function of Oddi＇s sphincter with normal pancreatobiliary confluence and pancreatobiliary reflux

Abstract

Objective To explore the impact of basal sphincter of Oddi （SO） pressure on pancre- atobiliary reflux （PBR）. Methods A total of 120 consecutive patients who received therapeutic ERCP for biliary tract diseases with or without the history of EST were enrolled, and were assigned to normal basal SO pressure group （n = 23 ）, elevated basal pressure group （ n = 55 ） and EST group （ n = 24）. Basal SO pressure, bile amylase （BA）and bacteria culture findings were compared between the three groups. Results There were no differences in positive rate of bacteria culture, SO pressure increase and BA between the normal basal SO pressure group and elevated basal pressure group. In the latter group, negative correlation was observed between SO pressure and BA. The BA value [ median（ quartile range） ] in patients with common bile duet I〉 15 mm [4270 （12 337）U/L] was significantly higher than that in patients with common bile duct 〈 15 mm [ 279. 5 （1370）U/L]. Furthermore, significant difference in both the proportion of elevated BA patients （83.3% vs. 59.0% ） （P 〈0.05） and the positive rate of bacteria culture （75.0% vs. 33.3% ） was seen between the intact papilla patients in the former two groups and those in EST group （P 〈 0. 05 ）. Conclusion There was no direct correlation between the elevated basal SO pressure and PBR, but marked increase in diameter of common bile duct can lead to a rise in BA. Moreover, although EST can bring about PBR and bile bacterial infection, it may facilitate the outflow of the refluent pancreatic juice by relieving eholestasis. Key words: Sphincter of Oddi manometry; Normal pancreatobiliary junction; Biliary amylase; Pancreatobiliary reflux