SPECIALIZED IMAGING OF THE GALLBLADDER
The main function of your gallbladder is to store bile. Positioned under your liver, this small, pear-shaped organ is only four inches in size, yet it performs an important function.
Bile helps the body break down and digest fat. This allows fat-soluble vitamins and nutrients to be more easily absorbed into the bloodstream. Bile is produced in the liver and stored in the gallbladder. It’s then sent into your small intestine via bile ducts when it’s needed.
The most common problems affecting your gallbladder usually involve a blockage in the bile ducts. Gallstones (cholelithiasis) are the most common cause of blockages. They develop when substances, such as cholesterol, in the bile harden and form solid crystals.
Gallstones tend to occur more often in women compared to men, and their prevalence increases with age and obesity. According to the Canadian Liver Foundation, up to 20 percent of women and 10 percent of men will be affected by gallstones by the age of 60.
Inflammation of the gallbladder, or cholecystitis, can also occur when bile ducts become blocked. It can be acute (short-term) or chronic (long-term).
WHAT ARE THE SYMPTOMS OF GALLBLADDER CONCERNS?
Pain that occurs in the mid- to upper-right section of your abdomen is the most common symptom of a gallbladder problem. The level and frequency of this pain can vary from mild and intermittent to quite severe and frequent. It can also radiate to other areas of the body, such as the back and chest.
Other symptoms of gallbladder issues include:
- Nausea or vomiting
- Fever or chills – these could be signs of infection
- Chronic diarrhea
- Jaundice or yellow-tinted skin
- Unusual stools or urine, such as lighter-colored stools and dark urine
HOW ARE GALLBLADDER CONCERNS DIAGNOSED?
To diagnose a gallbladder problem your health care practitioner will often perform a physical exam, review your medical and family history, and discuss how long symptoms have been present and how they affect daily activities. Blood tests or medical imaging, such as an abdominal ultrasound or CT scan, may also be requested. In some cases, a hepatobiliary iminodiacetic acid (HIDA) scan may also be appropriate.
During a HIDA scan a small amount of radioactive material (called a radiopharmaceutical) is injected into a vein that travels through your bloodstream into your liver, where the bile-producing cells take it up. It then travels with the bile into your gallbladder and your small intestine. A gamma camera detects the radiation emitted from your body, which is put together by a computer that creates images of the biliary system.
This scan evaluates the gallbladder, looks at the bile-excreting function of your liver, and tracks the flow of bile from your liver into your small intestine. It can help diagnose:
- Gallbladder inflammation (cholecystitis)
- Bile duct obstruction
- Congenital abnormalities in the bile ducts, such as biliary atresia
- Postoperative complications, such as bile leaks and fistulas
Your doctor might also use a HIDA scan to measure gallbladder ejection fraction – the rate at which bile is released from your gallbladder.
WHAT HAPPENS DURING A HIDA SCAN?
Prior to your exam you will need to ensure you’ve had no barium studies for one week. You will be asked not to eat, drink, smoke, or chew anything six hours prior to your exam, and avoid opiates or analgesics such as Demerol, Morphine or Percocet for four hours prior to the study. We suggest you wear comfortable clothing free of large metal buttons.
Please notify your technologist if you are claustrophobic, if there’s a chance you may be pregnant, or if you are nursing. If you are pregnant, the exam will need to be postponed. If you are uncertain, a blood test will be required to confirm you are not pregnant prior to starting the exam. This may delay or postpone your appointment if not obtained in advance. If you are nursing, you will be given further instructions regarding breastfeeding.
Before the exam begins, you will be asked to empty your bladder. Once the exam begins, your technologist will ask you to lie on your back on the imaging bed and will position the gamma camera over your abdominal area. A radioactive material (radiopharmaceutical) will then be injected into a vein in your arm.
Imaging will begin immediately after your injection and continue for 60 minutes. While the images are being acquired, try to hold as still as you can. You may breathe normally, but movement may blur the images, making them more difficult to interpret. The scan is painless, but please let your technologist know if you are not comfortably positioned on the bed.
If the gallbladder has filled up with the radiopharmaceutical within 60 minutes, you will be asked to drink Boost. This will encourage your gallbladder to contract. Two, three-minute images will be taken before the Boost and the same two, three-minute images are taken approximately one hour after the Boost.
You will be required to stay in the clinic for the duration of the study, which will take approximately two hours. If you’ve had your gallbladder surgically removed (a cholecystectomy), the technique for the study will be slightly different and this version of the study will take approximately one-and-a-half hours.
IS A HIDA SCAN SAFE?
The radiopharmaceutical is excreted from the body through your urine and will decay within the body over the 48 hours following your exam. Keeping hydrated and voiding frequently will help eliminate it from your body.
A HIDA scan involves a small dose of ionizing radiation from the radiopharmaceutical injected into your vein. Overall, the radiation exposure from a HIDA scan is about the equivalent of exposure to the earth's natural background radiation over two years. In most cases, the benefits, such as the early detection of a serious illness, outweigh the small increased risk from radiation exposure.
Mayfair Diagnostics complies with policies and has procedures in place for nuclear medicine radiation safety, including a Radiation Safety Officer who ensures we follow all policies and procedures. If you are pregnant, or if there is a chance you are pregnant, we will not perform the exam. If you are breastfeeding, please inform the technologist. The exam will still be performed, but you will be advised to pump and discard breast milk, or store it for a specific period of time before using.
HOW DO I GET A HIDA SCAN?
This exam is covered under your Alberta Health Care Insurance Plan and must be requested by a health care practitioner. If it’s indicated as a best next course of action, your doctor will provide you with a requisition and the appointment can be booked.
HIDA are only performed at our Mayfair Place location, please visit our services page for more information about this exam.
Holland, K. (2019) "Identifying Gallbladder Problems and Their Symptoms." www.healthline.com. Accessed June 15, 2021.
Phillips, Q. (2020) “What Are Common Gallbladder Problems? Symptoms, Causes, Diagnosis, Treatment, and Prevention.” www.everydayhealth.com. Accessed June 15, 2021.