HIDA scan

Normal scan   After fatty meal

• A HIDA scan is an imaging test used to examine the gallbladder and the ducts leading into and out of the gallbladder. 
• How it is done
  • The patient receives an intravenous injection of a radioactive material called hydroxy iminodiacetic acid (HIDA).
  • The HIDA material is taken up by the liver and excreted into the biliary tract.
  •  In a healthy person, HIDA 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 makes its way out of the body in the stool.
  • HIDA imaging is done by a nuclear scanner, which takes pictures of the patient's biliary tract over the course of about two hours. 
  • The images are then examined by a radiologist, who interprets the results. 
• Safety
  • It is generally a very safe test and is well tolerated by most patients.
• Indication
  • Usually, HIDA scans are ordered for patients who are suspected of having an obstruction in the biliary tract, most commonly those who are thought to have a stone blocking the cystic duct leading out of the gallbladder.
  • Such a scenario is consistent with acute cholecystitis, which often requires surgical removal of the gallbladder.
  • In cholecystitis, HIDA will appear in the bile ducts, but it will not enter the cystic duct or the gallbladder -- a finding that indicates obstruction.
  • If the HIDA 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.
• Cost
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