There are many tests to diagnose gallstones and evaluate the biliary (gallbladder) system.
The most common and simple test is an abdominal ultrasound. An ultrasound can determine: 1) if you have gallstones and 2) if any signs of an infection of the gallbladder are also present.
If other complications from gallstones are suspected, a CT (cat scan) or MRI may be ordered. These tests can determine: 1) if pancreatitis is present and it’s severity, 2) if gallstones have migrated to the main bile duct and are causing jaundice and, 3 ) if any dilation of the biliary system is present which would result from gallstones getting stuck in a biliary duct and causing an obstruction.
If biliary dyskinesia is suspected, a HIDA scan may be ordered. A HIDA scan is a nuclear medicine study that evaluates gallbladder function. A HIDA scan measures how well the gallbladder empties bile out of the gallbladder into the main common duct. Normal emptying (or ejection fraction) of the gallbladder is around 35%. If the ejection fraction is lower (less than 20%), this usually signifies biliary dyskinesia.