What is the procedure for a Hepatobiliary Iminodiacetic Acid (HIDA) scan?

From the Guidelines

The procedure for a HIDA scan involves injecting a radioactive tracer intravenously, followed by imaging with a gamma camera to visualize the gallbladder and biliary system, with the patient fasting for several hours before the test. The procedure begins with the patient receiving an injection of a radioactive tracer, typically technetium-99m labeled iminodiacetic acid, through an IV line 1. The patient then lies on an imaging table while a gamma camera takes pictures as the tracer moves through the biliary system. Some key steps in the procedure include:

• Injecting the HIDA radiotracer intravenously with the patient supine on the imaging table 1
• Obtaining imaging up to 1 hour to ensure visualization of the gallbladder prior to sincalide infusion 1
• Placing the camera in the left anterior oblique projection (35– 40 degrees) for imaging to ensure minimal overlap of the gallbladder with duodenum and small bowel, if the gallbladder has filled 1 The scan typically takes 1-4 hours, depending on how quickly the body processes the tracer. Sometimes, a medication called cholecystokinin (CCK) may be administered during the test to stimulate gallbladder contraction. The procedure is painless except for the initial needle stick, and no special preparation is needed afterward, though drinking plenty of fluids helps eliminate the tracer 1. This test is particularly useful for diagnosing gallbladder inflammation, bile duct obstruction, bile leaks, and assessing gallbladder function when gallstones are suspected but not visible on other imaging tests. It's worth noting that a HIDA scan is considered the gold standard for diagnosing acute cholecystitis and is far less costly than other imaging modalities like MRI/MRCP 1.

From the FDA Drug Label

Following intravenous administration in normal subjects, Technetium Tc 99m Mebrofenin was rapidly cleared from the circulation. The mean percent injected dose remaining in the blood at 10 minutes was 17% The injected activity was cleared through the hepatobiliary system with visualization of the liver by 5 minutes and maximum liver uptake occurring at 11 minutes post-injection. Hepatic duct and gallbladder visualization occurred by 10 to 15 minutes and intestinal activity was visualized by 30 to 60 minutes in subjects with normal hepatobiliary function.

The procedure for a HIDA scan involves:

• Intravenous administration of Technetium Tc 99m Mebrofenin
• Visualization of the liver, hepatic duct, and gallbladder at specific time points:
  • Liver: 5 minutes
  • Maximum liver uptake: 11 minutes
  • Hepatic duct and gallbladder: 10 to 15 minutes
  • Intestinal activity: 30 to 60 minutes 2

From the Research

HIDA Scan Procedure

The procedure for a HIDA scan involves several steps:

• Patient preparation: The patient should fast for at least 4 hours or overnight before the scan 3
• Injection of radioactive tracer: The patient is injected with a small amount of radioactive tracer, usually technetium-99m mebrofenin or technetium-99m hepato imino diacetic acid (HIDA) 4, 5
• Imaging: The patient is then imaged using a gamma camera to visualize the uptake and excretion of the tracer by the liver and gallbladder 4, 5
• Pharmacological intervention: In some cases, pharmacological intervention with cholecystokinin-8 (CCK-8) or morphine may be used to assess gallbladder function or to diagnose acute cholecystitis 3
• Interpretation of results: The results of the HIDA scan are interpreted by a nuclear medicine physician, who looks for signs of abnormal gallbladder function, biliary obstruction, or other hepatobiliary disorders 6, 5

Special Considerations

• Patients with neonatal cholestasis may undergo a HIDA scan to diagnose biliary atresia 4
• Patients with typical biliary pain and a normal trans-abdominal ultrasound (TUS) scan may undergo a HIDA scan to assess gallbladder function 6
• Patients scheduled for major liver resection may undergo a HIDA scan to assess liver function and determine the risk of posthepatectomy liver failure 7

Imaging Protocol

• The HIDA scan typically involves imaging the patient at 5 minutes, 30 minutes, 60 minutes, and 24 hours after injection of the tracer 4
• The patient may be given a fatty meal or a pharmacological agent, such as CCK-8, to stimulate gallbladder contraction and assess gallbladder function 3, 6
• The HIDA scan may be performed in conjunction with other imaging modalities, such as ultrasound or computed tomography (CT), to provide a more comprehensive evaluation of the hepatobiliary system 5