Intraoperative sphincter of Oddi manometry in patients with gallstones.

In seven patients operated on with cholecystectomy for simple gallstones, sphincter of Oddi manometry was performed during surgery. The sphincter was localized as a zone with elevated base-line pressure and phasic contractile activity. Mean value of the amplitude was 90 mm Hg; wave duration, 4 sec; frequency, 5/min; and base-line pressure, 10 mm Hg. No activity was seen in the antrum or duodenum. The plotting of peak-to-peak intervals in a histogram showed that these were evenly distributed around 6 sec or at integrated multiples of this value. This indicates that the sphincter of Oddi is paced. The origin of the pacing is not yet established.