Evaluation of the Gallbladder Ejection Fraction by Tc-99m DISIDA Scintigraphy after Gastric Operations

ABSTRACT

BACKGROUND : Truncal vagotomy produces a reduction in bile flow, an increased gallbladder volume, a delay in gallbladdr emptying, decrease in resting pressure, and decreased contraction following stimulation with cholecystokinin. Retrospective studies have suggested that vagotomy can be responsible for a 4 to 6 fold increase in the 4% to 5% control rate of cholelithiasis noted in the Framingham study. The measurement of the gallbladder ejection fraction by using Tc-99m DISIDA scintigraphy is suitable for the study of the motor functions of the gallbaldder. A gallbladder ejection fraction of less than 35% is highly predictive of the presence of gallbladder disease and is a good indicator of a favorable outcome following a cholecystectomy. METHODS : Between January 1995 and December 1996, 24 patients (truncal vagotomy + pyloroplasty, 5; truncal vagotomy partial + gastrectomy + Billroth I, 4; truncal vagotomy + partial gastrectomy + Billroth II, 12; total gastrectomy, 3) and 18 healthy volunteers were investigated prospectively by Tc-99m DISIDA scintigraphy for the measurement of the gallbladder ejection fraction. RESULTS : In normal subjects, the mean value of the gallbladder ejection fraction was 70.8%, and in patients after a gastric operations, it was 66.0% (p>0.05). Three (25.0%) of the 12 patients with a truncal vagotomy, partial gastrectomy, and Billroth II gastrojejunostomy had gallbladder ejection fractions of less than 35% (p<0.05). CONCLUSIONS : There was no difference in the gallbladder ejection fractions between the control group and the patients after gastric operations, including a truncal vagotomy. However there was a significant difference between the patients with a truncal vagotomy, partial gastrectomy, and Billroth II anastomosis and those receiving other gastric operations.