Presentation
55-year-old man with right upper quadrant pain and fever.
Patient Data
A hepatobiliary scan was performed using 4 mCi ofTc99m-Choletec IV.
Initial 60 minutes of imaging performed using 5 minutes per acquisition. There is normal excretion of radiotracer into the common bile duct and duodenum see starting at 10 minutes. The gall bladder fails to fill over the 1-hour acquisition with an empty gall bladder fossa (dashed oval).
Left anterior oblique and right lateral images obtained at the end of 60 minutes confirms non-filling of the gall bladder (dashed ovals).
Delayed images obtained at 4 hours show persistent non-filling of the gall bladder (dashed ovals).
In the appropriate clinical setting, findings are consistent with acute cholecystitis.
Case Discussion
Hepatobiliary scintigraphy is useful for the diagnosis of acute cholecystitis.
To avoid false-positive exams, it is important that the patient be fasting for at least 4 hours prior to the exam to include no TPN. Recent caloric intake can stimulate the endogenous secretion of CCK which causes gall bladder contraction and potentially prevents its filling by the radiotracer. Likewise, if the patient has been fasting for too long (generally >24 hours), the bile in the gall bladder can become viscous and prevent normal filling with the radiotracer, simulating acute cholecystitis. In such instances, it is recommended to pre-treat the patient with CCK at least 30 minutes before the exam.