If the gallbladder is not clearly seen on the X-ray, the test may be repeated the next morning after a double dose of dye tablets. Factors affecting results Movement during the test. Failure to take a full dose of dye tablets. If your bowel does not absorb the contrast material, the gallbladder may not be visualized on X-ray films. The doctor examines the X-ray film, called a cholecystogram, for evidence of disease.
Gallstones usually show up as dark spots against a bright background.
If the gallbladder is sluggish or infected, other abnormalities of shape or structure may be detected. It provides a better view of the gallbladder than regular X-rays. It also demonstrates radiolucent gallstones not seen on plain films of the abdomen. It entails exposure to radiation. There is a risk of adverse reactions to the contrast dye.