A HIDA scan, also known as a hepatobiliary iminodiacetic acid scan, is a medical imaging test used to evaluate the function and structure of the gallbladder and bile ducts. The test involves injecting a small amount of radioactive material into the bloodstream, which is then absorbed by the liver and excreted into the bile. The radioactive material accumulates in the gallbladder and bile ducts, allowing doctors to visualize these areas using a special camera. In this article, we will explain the HIDA scan procedure, its uses, and what to expect during and after the test.
What is a HIDA Scan?
A HIDA scan is a type of nuclear medicine test that uses a radioactive tracer to image the liver, gallbladder, and bile ducts. The test is commonly used to diagnose gallbladder disease, including gallstones, cholecystitis, and biliary obstruction. The HIDA scan can also be used to evaluate liver function and detect certain liver diseases.
How Does a HIDA Scan Work?
During a HIDA scan, a small amount of radioactive material, usually technetium-99m mebrofenin, is injected into the bloodstream. The radioactive material is then absorbed by the liver and excreted into the bile. The liver and bile ducts absorb the radioactive material, which accumulates in the gallbladder. A special camera, called a gamma camera, is used to detect the radiation emitted by the radioactive material, allowing doctors to visualize the gallbladder and bile ducts.
| Radioactive Material | Description |
|---|---|
| Technetium-99m mebrofenin | A commonly used radioactive tracer for HIDA scans |
Preparation and Procedure
Before undergoing a HIDA scan, patients are usually asked to fast for 4-6 hours to ensure that the gallbladder is empty. The test typically takes 30-60 minutes to complete. During the test, patients lie on a table and a gamma camera is placed over the abdomen. The radioactive material is injected into the bloodstream, and images are taken at regular intervals.
What to Expect During a HIDA Scan
During the test, patients may be asked to remain still and hold their breath for short periods. The gamma camera may move over the abdomen to take images from different angles. Some patients may experience mild discomfort or anxiety during the test, but this is usually minimal.
Key Points
- A HIDA scan is a non-invasive test used to evaluate gallbladder and bile duct function.
- The test involves injecting a small amount of radioactive material into the bloodstream.
- A gamma camera is used to detect radiation emitted by the radioactive material.
- The test typically takes 30-60 minutes to complete.
- Patients may be asked to fast for 4-6 hours before the test.
Interpretation of Results
The results of a HIDA scan are interpreted by a radiologist or nuclear medicine specialist. The images obtained during the test are evaluated for signs of gallbladder disease, such as gallstones, inflammation, or obstruction of the bile ducts. The test can also be used to evaluate liver function and detect certain liver diseases.
Abnormal Results
Abnormal results on a HIDA scan may indicate gallbladder disease, such as:
- Gallstones
- Cholecystitis (inflammation of the gallbladder)
- Biliary obstruction
- Liver disease
Advantages and Limitations
A HIDA scan has several advantages, including:
- Non-invasive and painless
- Can detect gallbladder disease and liver dysfunction
- Can be used to evaluate patients with suspected gallbladder disease
However, the test also has some limitations:
- May not detect all cases of gallbladder disease
- May require additional testing to confirm diagnosis
- Exposure to small amounts of radiation
What is the purpose of a HIDA scan?
+A HIDA scan is used to evaluate the function and structure of the gallbladder and bile ducts. It can help diagnose gallbladder disease, including gallstones, cholecystitis, and biliary obstruction.
How long does a HIDA scan take?
+A HIDA scan typically takes 30-60 minutes to complete.
Is a HIDA scan safe?
+A HIDA scan is generally considered safe. The test involves exposure to small amounts of radiation, but this is usually minimal.
In conclusion, a HIDA scan is a valuable diagnostic tool for evaluating gallbladder and bile duct disorders. The test is non-invasive, painless, and can provide valuable information about liver function and gallbladder disease. While the test has some limitations, it remains an important part of the diagnostic workup for patients with suspected gallbladder disease.