Investigation of the effect of duodenoscopy on sphincter of Oddi manometry.

To investigate whether endoscopy affects sphincter of Oddi (SO) manometry, three patients who had undergone previous cholecystectomy and had a T-tube in situ for drainage were studied. Manometry was performed using a perfused triple lumen manometry catheter (diameter 1.7 mm), which was advanced into the SO lumen through the T-tube. SO motility, baseline pressure, common bile duct pressure and duodenal pressure were monitored before and during endoscopy while the tip of the endoscope was in the mouth, esophagus (upper third, precardial), stomach and duodenum. Endoscopy and even a moderate insufflation of air necessary to pass the pylorus and inspect the papilla of Vater did not affect the parameters mentioned. Thus, ERCP manometry is a reliable method for evaluation of SO motility which is not affected by endoscopy. Duodenal pressure is a stable parameter and suitable for serving as reference pressure.