Gallbladder function: methods for measuring filling and emptying.

Cholescintigraphy with [99mTc] disofenin was used to determine the optimal dose and method of administration of the octapeptide of cholecystokinin, and to determine the kinetics of gallbladder filling and emptying in 22 patients without disease of the liver or gallbladder. The peak filling rate of the gallbladder occurred at 30 min after injection; filling was complete at 1 hr. A 45-min constant intravenous infusion of the octapeptide 20 ng/kg X hr resulted in progressive emptying of the normal gallbladder; the mean ejection fraction at 45 min was 77.2 +/- 4.9%. A 1-min injection of 20 ng/kg resulted in a rapid, short-lived emptying; the mean ejection fraction was 52.2 +/- 9.3%. Doubling or halving the infusion dose produced no greater response or a smaller response. We conclude that a constant 45-min infusion technique is superior to short injection times, because of more complete emptying, no side effects, and more consistent response.