A HIDA (Hepatobiliary Iminodiacetic Acid) Scan is a Nuclear Medicine procedure performed to diagnose problems with the liver, gallbladder, and bile ducts. The gallbladder is a sac (bladder) tucked behind your liver that is used to concentrate and store digestive juices (bile) created by the liver.
When you eat foods containing fat the gallbladder empties the bile into the small intestine to help digest the fat.
A HIDA scan can be used to help track bile flow through your liver to your small intestine and also to diagnose several diseases such as:
- Gallbladder inflammation (cholecystitis)
- Bile duct obstruction
- Bile leak
- Congenital abnormalities in the bile ducts
Preparation
To prepare for a HIDA scan you are required to be fasting for 4 hours prior to the test. If you haven’t eaten anything for more than 24 hours prior to the test please let the technologist know. You are also to avoid taking any opiate-based drugs (morphine, fentanyl, oxycodone, etc.) for 12 hours prior to the test.
PLEASE INFORM YOUR DOCTOR OR THE TECHNOLOGIST IF YOU ARE,
OR THINK YOU MIGHT BE, PREGNANT OR BREASTFEEDING.
Procedure
Check-in at the Diagnostic Imaging Department at the Sault Area Hospital for your appointment.
To perform your HIDA scan your abdomen will be positioned underneath our camera with the camera heads brought in close. Your head will not have to go underneath the camera. Once positioned the technologist will give you an injection containing a very small amount of a radioactive tracer (Technetium-99m Disofenin). The radioactive tracer will be taken out of your blood by your liver (hepatocytes) and converted into bile. The bile will travel through the bile ducts into the gallbladder or small intestine as it is produced. The camera will be taking pictures during this time and images will be acquired until we see your gallbladder fill. It can take anywhere from 30 minutes to over an hour for your gallbladder to fill.
If your gallbladder does not fill you may be required to return 3 hours later to evaluate if the gallbladder fills over time. During the 3 hour delay, you must continue fasting. When you return it may be necessary to evaluate the gallbladder emptying.
If your gallbladder fills you may be required to have a second test to evaluate how the gallbladder empties. To perform the second test you will be given a drink (Ensure) to stimulate the gallbladder to contract and empty the bile into your small intestine. You will be positioned under the camera again and pictures will be obtained over the course of 45 minutes to track the bile as it exits the gallbladder. During this time you may experience sensations from the Ensure that you may experience when eating fatty foods.
Following your test, there are no restrictions and you will be able to drive as you normally would. If you are planning on going into the United States of America you will set off the radiation detectors for approximately 2-3 days. We can provide a letter explaining why you are setting off the detectors however you will still be stopped.
Once your scan is complete it will be examined by a radiologist and a report will be sent to the ordering doctor within a week. Follow up your test with the ordering physician or your family doctor.
The Injection
The amount of radioactive tracer injected for a HIDA scan is small enough that there are no additional requirements or precautions to protect others from radiation exposure. The radiation exposure to you is less than most standard x-rays. Most of the injection will be cleared out of your body after 24 hours.
Allergic reactions to the material are extremely rare, and you should not feel anything or notice any changes from the material injected.
The Camera
For a HIDA scan, we acquire the images using a gamma camera. A gamma camera is a type of radiation detector that is used to show us how the radioactive tracer travels through your biliary system. Our cameras do not emit radiation or loud noises and are not a hazard to anyone in the vicinity while acquiring.