I had HIDA about 6 years ago, if I recall u eat a cheeseburger and they do the scan. They found my bile duct transfer or whatever it's called was at about 17%. Didn't seem to bother me at the time. I have thus far forestalled surgery since then, for which I credit drinking half of a small lemon in soda water (soda just taste preference, not required) daily. But this week the ol' GB pain came back, and I again quit eating fat. Pain is improving, but I'm afraid I'll have to do surgery. Keep your fingers crossed for me.
Heh, I just now did what you should've done and googled HIDA Scan where I found this:
"If you’re having problems with your gallbladder, your doctor may want you to have a special test called a hepatobiliary iminodiacetic acid (HIDA) scan.
During the procedure, a technician injects a tiny amount of a radioactive compound into your bloodstream. As it travels through your liver, gallbladder, and small intestine, a camera tracks its movement and takes pictures of those organs.
A HIDA scan shows how well your gallbladder is working. It can also check your liver function, since these two organs work closely together."
Click the link, read it, there's much more.