A Hepatobiliary (HIDA) scan is an imaging procedure used to diagnose problems in the liver, gallbladder and bile ducts. Nuclear Medicine is an imaging technology that involves the use of small amounts of radioactive materials (or tracers) to help diagnose and treat a variety of diseases. Nuclear medicine determines the cause of the medical problem based on the function of the organ, tissue or bone.
This test uses a small amount of radioactive material to emit photon energy. This energy is detected by a gamma camera which then captures and creates computerized images.
When would I get a HIDA Scan?
Your doctor may use a HIDA scan as part of a test to measure the rate at which bile is released from your gallbladder. This rate is called gallbladder ejection fraction.
An ejection fraction of greater than 35 percent is considered normal. When the ejection fraction is less than 35 percent, a diagnosis of biliary dyskinesia is made. Since this organ is not necessary for living a healthy life, surgical removal of the gallbladder may be considered.
A HIDA scan is also used to look at the biliary excretion function of your liver and to track the flow of bile from your liver into your small intestine. A HIDA scan images liver function, which complements images of body structure (anatomy) provided by x-ray and ultrasound.
A HIDA scan may help in the diagnosis of several diseases and conditions, such as:
- gallbladder inflammation known as cholecystitis
- bile duct obstruction
- congenital abnormalities in the bile ducts, such as biliary atresia
- postoperative complications, such as bile leaks and fistulas
- the assessment of a liver transplant.
What Will I Experience?
In a HIDA scan, a radioactive chemical or tracer is injected into a vein in your arm.
The tracer is handled by the liver like bile. Bile is a fluid produced and excreted by your liver that helps your digestive system break down fats in the foods you eat. Bile is stored in your gallbladder and the gallbladder releases the bile when you eat a meal.
When it is time for the imaging to begin, the gamma camera will take a series of images. The camera may rotate around you or it may stay in one position and you may be asked to change positions in between images. While the camera is taking pictures, you will need to remain still for brief periods of time.
After the initial series of images is taken, you may be given a medication that causes your gallbladder to empty. Additional images will be taken as your gallbladder empties.
The radiopharmaceutical you receive for the study is eliminated from your body through the urine. For that reason, you should drink plenty of fluids and urinate frequently after completion of the test. How much fluid will depend on each individual, but you should be well hydrated.
For an adult this could be three to four glasses of water.
Your urine will not change color. Your urine will contain the radioactive material, so it is recommended that you thoroughly wash your hands after going to the bathroom.
Typically, a HIDA scan will take approximately one to four hours to complete.