Improving Hepatobiliary Imaging as a Physiologic Test with Superior Clinical Outcomes

Abstract

This study aims at prospectively evaluating the difference in the effect of cholecystokinin (CCK) and half-and-half milk (HHM) administered in the same patient on gallbladder contractility and correlation with clinical outcomes. Upon gallbladder visualization during standard hepatobiliary imaging, 0.02 μg/kg of CCK was injected over 3 min, and additional 30 min of dynamic imaging was obtained. Patients with gallbladder ejection fraction (GBEF) <35% after CCK were administered 8 oz of HHM followed by 30 min of imaging. The GBEF was recalculated. The number of patients whom GBEF changed from below 35% (abnormal) after CCK to above 35% (normal) after HHM was recorded. Follow-up of the clinical outcome at 6 months was performed. Fifty patients with abnormal GBEF were prospectively included. The average GBEF after CCK was 14.7% ± 8.5% and after HHM was 30.7% ± 20.8%. The average increase in GBEF with HHM was 16.0% ± 22.2%. The GBEF changed from abnormal to normal in 17 patients (34%). The remaining 33 patients remained abnormal. Clinical outcomes at 6 months were available in 47 patients. Cholecystectomy was performed in 60% of patients with abnormal GBEF with CCK and HHM with resolution or improvement of pain. Two of 16 patients (12%) with abnormal GBEF after CCK but normal after HHM had cholecystectomies with pain improvement, while 8 out of these patients (50%) were diagnosed and treated with other disorders and improved. Hepatobiliary imaging with HHM stimulation is a superior physiologic test which can lower the number of unnecessary cholecystectomies and misdiagnoses as functional cholecystitis.

Keywords: Cholecystokinin; cholescintigraphy; fatty meal; gallbladder ejection fraction; hepatobiliary imaging; milk.

Figure 1

The same patient sequential images and time activity curve of the gallbladder after cholecystokinin administration (a) with a calculated gallbladder ejection fraction 20% and after half and half milk administration (b) with a calculated gallbladder ejection fraction 51%

Figure 2

Significant change in gallbladder ejection fraction in the same patient from abnormal 27% after cholecystokinin stimulation (a) to normal 88% after half and half milk stimulation (b)

Figure 3

Unchanged abnormal gallbladder ejection fraction in a patient after cholecystokinin stimulation (a) calculated as 12% and after half and half milk stimulation (b) calculated as 4%

Figure 4

Comparison of the time-activity curve and gallbladder contractility in the same patient after cholecystokinin (a) showing a brief mild contraction followed by relaxation when the cholecystokinin effect fades versus after half-and-half milk (b) showing smooth gradual increasing gallbladder contraction