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About HIDA (Hepatobiliary) scans
You will receive an injection in your arm of a radioactive compound that will be filtered by your liver, collected in your gallbladder, and excreted into the bowel. The radioactive material is of a very low level and is considered by physicians to be safe. Patients usually have no side effects from the injection. For this test, you will lie on an imaging table under a nuclear scanner, which takes pictures of the patient's biliary tract over the course of about two hours. Multiple images are obtained of your abdominal area. The images are then examined by a radiologist, who interprets the results. It is generally a very safe test and is well-tolerated by most patients. This procedure usually takes 1-2 hours (sometimes longer) because it is a functional procedure and it is not possible to predict how quickly your liver will uptake the material or when your gallbladder will become visible to the nuclear scanner. Once the gallbladder is seen, either a second injection of the material, or injection of a different substance, is sometimes given to spur the gallbladder to begin excreting the bile. This second procedure will take an additional 20 minutes and may cause symptoms of nausea, vomiting, or abdominal pain. Different findings on the test can mean different things. If the gallbladder is not seen by the scanner, often blockage of the cystic (gallbladder) duct is present. This can accompany acute or chronic gallbladder infection (cholecystitis) and is often a reason to surgically remove the gallbladder (cholecystectomy). In cholecystitis the radioactive HIDA substance will appear in the bile ducts, but it will not enter the cystic duct or the gallbladder, a finding that indicates obstruction. If the substance enters the bile ducts but does not enter the small intestine, then an obstruction of the bile duct (usually due to stones or cancer) is suspected. Sometimes the test is also used to determine the contractile function of the gallbladder; that is, how well does the gallbladder squeeze out the bile. In this fractional excretion variant of the HIDA scan, not unlike a "gallbladder stress test," people who have chronic gallbladder malfunction and symptoms without the presence of gallstones are identified. Many of these people will get symptom relief from gallbladder removal. Your doctor or other healthcare provider is the best person to help sort out the right time to consider a HIDA scan. |
A
very useful tool for evaluating the liver, gallbladder, and biliary system is
called the Hepatobiliary (HIDA) scan. This scan demonstrates not only liver
function, but also the function of the gallbladder. It is commonly used to
diagnose abnormal function of the gallbladder. It also examines the gallbladder
and the ducts leading into and out of the gallbladder. Many people have
gallstones without ever having symptoms. However, these stones can cause acute
abdominal pain by obstructing the gallbladder and the flow of bile. This is a
very simple test to determine if gallbladder is obstructed. In this test the
patient receives an intravenous injection of a radioactive material called
hydroxy iminodiacetic acid (HIDA). This
material is taken up by the liver and excreted into the biliary tract. In a
healthy person, this material will pass through the bile ducts and into the
cystic duct to enter the gallbladder. It will also pass into the common bile
duct and enter the small intestine, from which it eventually passes out of the
body in the stool.