Cholecystokinin enhanced hepatobiliary scanning with ejection fraction calculation as an indicator of disease of the gallbladder. Chronic acalculous cholecystitis represents 5 to 20 per cent of electively treated diseases of the gallbladder. A 70 per cent success rate in relieving these patients of chronic pain was reported when surgical treatment was recommended based on symptoms alone. The cholecystokinin ejection fraction, which is a quantitative measure of emptying of the gallbladder, was 95 per cent accurate in predicting which patients would be relieved of symptoms by surgical treatment. In this study, we report our consecutive experience during a 20 month period with 83 patients. 