Cholescintigraphy (cont.)

What are the limitations of cholescintigraphy?

Nonvisualization (the failure of the gallbladder to appear on a cholescintigraphy scan) of the gallbladder occurs because of disease of the gallbladder, particularly gallstones. However, nonvisualization does not necessarily mean that the obstruction is the cause of the patient's problem. For example, patients with gallstones often have a nonvisualizing gallbladder due to obstruction of the cystic duct, but the obstruction causes no symptoms. Thus, cholescintigraphy is helpful only if the patient's problem is likely- based on the history and physical examination-to be due to disease of the gallbladder or bile ducts.

With the use of cholecystokinin, poor contraction of the gallbladder can be seen in some normal individuals. Therefore, reduced contraction does not always mean that the gallbladder is diseased. Again, cholescintigraphy with cholecystokinin is helpful only if the patient's problem is likely-based on the history and physical examination-to be due to disease of the gallbladder or bile ducts.

Another limitation of cholescintigraphy is that this test does not work when the patient's serum bilirubin is greater than 15-20 mg%.

What are the side effects of cholescintigraphy?

There are few side effects to cholescintigraphy. Reactions to the radioactive chemical and cholecystokinin are rare. The amount of radioactivity that patients are exposed to is small. The radioactive compound is eliminated in the stool, and the radioactivity deteriorates rapidly within hours.

What alternatives are there to cholescintigraphy?

Other common means of evaluating the gallbladder and bile ducts include ultrasonography and computerized tomography (CT or CAT scan). Cholangiography, either percutaneous (through the skin) or endoscopic (ERCP) (inserted down the throat), is a radiological procedure in which dye is injected into the gallbladder and bile ducts and then x-rays are taken. Newer procedures include endoscopic ultrasonography and magnetic resonance imaging (MRI) cholangiography. Oral cholecystography in which x-rays are taken of the gallbladder following ingestion of a dye that is concentrated in the gallbladder, is rarely done.

Last Editorial Review: 4/22/2002

Source: MedicineNet.com
http://www.medicinenet.com/cholescintigraphy/article.htm