Motility of Oddiʹs sphincter: Recent developments and clinical applications

Background In recent years, applications of electromyographic, cineradiographic, scintilographic, and endoscopic manometric techniques have improved our knowledge of normal and abnormal motility of Oddiʹs sphincter. This sphincter coordinates the time and rate of secretion of about 3 liters of bile and pancreatic juice into the duodenum daily. Methods Oddiʹs sphincter may be evaluated by endoscopic manometry, ultrasound, dynamic hepatobiliary scintigraphy, and laboratory tests. Endoscopic manometry is the best method for evaluating the function Oddiʹs sphincter. Results The basal pressure of Oddiʹs sphincter is usually 5 to 15 mm Hg greater than the bile and pancreatic duct pressures. Phasic contractions of 50 to 150 mm Hg in amplitude and 3 to 8 contractions per minute in frequency are superimposed on the basal pressure. A small percentage of patients with gastrointestinal symptoms after cholecystectomy has sphincter of Oddi dysfunction, which may have structural abnormality (papillary stenosis) or functional abnormality (Oddiʹs sphincter dyskinesia). Conclusions Elevated basal pressure (> 40 mm Hg) is the most important manometric finding of Oddiʹs sphincter dysfunction. Endoscopic sphincterotomy is the treatment of choice for patients with Oddiʹs sphincter dysfunction and elevated basal sphincter pressure.