Can you tell me about gallbladder test are ok. gb testing for function ok. us of abdomen ok. what's the cause?

Routine tests: HIDA scan involves fasting for few hours prior to study. Patient injected IV with radiotracer usually Technetium- hida extracted from blood stream by liver. Imaging continusously performed by nuclear camera positioned above the abdomen.Scan visualzies liver, bile ducts, gall bladder,bowel.Once gall bladder filled CCK injected IV for contraction and function of gb.US shows anatomy, stones, sludge