Quantitative cholescintigraphy: assessment of gallbladder filling and emptying and duodenogastric reflux

To accurately quantitate dynamic events associated with gallbladder filling and emptying, we developed a cholescintigraphic technique in which the radionuclide 99mTc-HIDA excreted in bile was externally measured by a gamma camera interfaced to a computer programmed for data processing. Changes in activity with time were measured over the liver, bile ducts, gallbladder, small intestine, and stomach. The first 60 min were used to detect activity filling the gallbladder. Cholecystokinin was then infused at 0.020 U/kg/min for 30 min to initiate gallbladder contraction, while monitoring the evacuation of radionuclide into the small intestine and/or stomach. The stomach region was defined by a 99mTc-sulphur colloid swallow. With computer assistance, we were able to measure the rate at which the gallbladder filled, the fraction of liver activity that partitioned into the gallbladder instead of the duodenum, the rate of gallbladder empyting, and any gastric reflux. In 12 fasting, healthy subjects, three-fourths of the hepatic activity entered the gallbladder. After a 5-min time lag, gallbladder empyting commenced in response to the cholecystokinin, ejecting half its contents in 12 min, but still having a residual 25% after 30 min. Gallbladder evacuation was definitely slower in 6 patients with cholelithiasis, although filling appeared normal. One patient with gallstones underwent a repeat study after 4 mo on chenodeoxycholic acid therapy: Gallbladder filling, and especially emptying, deteriorated. Gastric reflux occurred only in 2 patients with gastroenterostomies who refluxed 2% of their gallbladder contents into the gastric remnant. Quantitative cholescintigraphy offers a new objective means to define gallbladder function and document bile reflux.