What is expected during a HIDA scan?

A HIDA scan (cholescintigraphy) can show whether you have problems with your common bile duct, cystic duct, or common hepatic duct (together, these are called the "biliary tree").

A HIDA scan also measures the ejection fraction of your gallbladder. This is the percentage of bile that the gallbladder ejects into the duodenum. The ejection fraction should be 35% to 75%.

All this is done by injecting hydroxy iminodiacetic acid (HIDA) into a vein while you are under a nuclear scanner. It takes about two hours.

During the test, your gallbladder will also be stimulated by a cholecystokinin-like substance to make it think that it needs to eject bile. (Cholecystokinin is produced by the small intestine, to tell the gallbladder, "send me some bile!")

You can get a very clear picture (or at least the radiologist and physician can) of gallbladder dysfunction using this diagnostic test.

Yes, the HIDA acid is radioactive, but it is a tiny amount, and it will pass out of your body within 24 hours if you hydrate properly.

This procedure should not affect your appendix.

I had negative blood tests, ultrasounds, CT scans, and MRIs of my gallbladder for 20 years. A HIDA scan finally showed it was ejecting at less than 27%, and out it came last year.

If you have not been tested for celiac disease (gluten intolerance/allergy), you may want to consider doing so. There is a simple blood test for antibodies, and some physicians prefer to also do an endoscopy to take a sample of the small intestine mucosa. It is important to know that you can be gluten intolerant and still test negative for celiac disease.

Your lower right quadrant pain, if not your appendix, could very well be your small intestine. You have 20 feet of small intestine, and you may want to search for images of the jejunum, cecum, and ileum, as well as the ileocecal valve. Conditions like gluten allergy and irritable bowel syndrome, or irritable bowel disease, can cause discomfort in that area.

Of all the GI diagnostic tests I have had, the HIDA scan was the least uncomfortable. I had some typical gallbladder-type pain after the test, because the test stimulates the gallbladder, but I had my gallbladder removed in August 2012 and do not regret having it done.

I'm so sorry you've had so much to deal with and at your age!

" I read that one girl had hers erupt during the procedure and that's what scares me." -- Had what erupt? Her gallbladder? Or appendix? It would be described as rupturing or bursting but this girl must've had a hot appy to begin with and it ruptured because it was going to anyway. But there's no reason why your appendix would rupture. There's nothing wrong with it, is there? From what I can gather, you don't have acute appendicitis -- if you did, you'd know -- and even if you had chronic appendicitis, the pain worsens over time (weeks) before it becomes acute.

"I've always had mild pain on my lower right side near the appendix and right colon." -- Now you need to explain "always". How long is that?

"If my gallbladder is not functioning so well, must I need to take it out?" -- That's usual course of action. Probably a laparoscopic cholecystectomy (lap-puh-row-SKAW-pic ko-lee-sis-TECK-to-mee and we call it a "lap choley" for short)

"Or can I just place myself on a healthy diet and live with it not working so well?" -- If the gallbladder is inflamed, it's beyond this.

"And will this procedure cause my appendix to erupt?" -- I can't think of any reason why it would.

"What is expected during a HIDA scan?" -- HIDA stands for hepatobiliary iminodiacetic acid, so you can see why we call it HIDA instead. It's pronounced HIGH-duh. You'll be asked to change into a hospital gown before the scan. Your health care team will position you on a table, usually on your back. A nurse will start an IV so that a radioactive tracer can be injected intravenously in your arm. You may feel some pressure during this part of the procedure, it's normal. The IV will remain throughout the scan and will be discontinued when it's done.

The tracer travels through your bloodstream to your liver, where it's taken up by the bile-producing cells. Then the tracer travels with the bile from your liver into your gallbladder and through your bile ducts to your small intestine.

As you lie on the table, a special gamma camera will be positioned over your abdomen taking pictures of the tracer as it moves through your body. The gamma camera takes pictures continually for about an hour.

You'll need to keep still during the scan. This can become uncomfortable, but you may find that you can lessen the discomfort by taking deep breaths and thinking about other things. Tell your health care team if you're unbearably uncomfortable.

The radiologist will watch on a computer the progress of the radioactive tracer through your body. The scan may be stopped when the radioactive tracer is seen in the gallbladder and enters your small intestine. This typically takes about an hour. In some cases extra imaging will be performed if the original images aren't satisfactory or clear enough, or if morphine is given to help visualize the gallbladder or if the medication CCK is given to look at the contraction of the gallbladder. The entire procedure should take about 2 hours.

When it's done, you'll get dressed and go home with some precautions. These should be repeated to you verbally and given to you in writing. You'll still have some of the tracer in your blood so you'll need to drink lots of water to help flush it from your system. It will excreted in your urine and stool for one to two days so you'll need to flush the toilet twice after using it. Wash your hands well. If you notice a rash within a few hours after having the scan or if you see a bruise at the IV site that gets larger, call your doctor and report it.

Your gallbladder isn't going to erupt during a HIDA scan. You may have some discomfort similar to the mild pain you've had in the past, or other symptoms related to the gallbladder. I had some mild nausea and cold sweats, followed by a lot of intestinal gurgling during the test. Afterward, I had some mild intestinal upset. It was nothing worse than if I had eaten a trigger food.