a test used in diagnosis of gallbladder conditions: 25 mL of a 25% solution of magnesium sulfate is delivered into the region of the sphincter of Oddi through a duodenal tube, causing contraction of the gallbladder, relaxation of the sphincter, and the expulsion of bile from the common duct and gallbladder; bile from the common duct is relatively pale and is expelled first, that from the gallbladder follows; samples aspirated from the tube are examined for pus cells, pigment granules, epithelial cells, cholesterol, and the like.
