Which of the following statement(s). is/are true concerning the diagnosis of biliary tract disease?

b. Ultrasonography has a diagnostic accuracy and sensitivity for cholelithiasis in excess of 95%

d. Hepatobiliary scintigraphy is primarily indicated to confirm the clinical diagnosis of acute cholecystitis

A number of radiographic studies can be used to diagnose cholelithiasis. Visualization of gallstones on plain abdominal radiographs is possible in about 20% of patients whose stones are grossly calcified. Traditionally, oral cholecystogram has been the gold standard for the diagnostic evaluation of patients with suspected gallstones. Although the accuracy for oral cholecystography has been reported to be as high as 95%, several conditions preclude satisfactory examination, including acute illness; poor patient compliance; inability to absorb the tablets as the result of emesis, malabsorption, or diarrhea; and jaundice or hepatic dysfunction. Abdominal ultrasonography has therefore become the preferred test for evaluation of patients with suspected gallstones. Most large series suggest that diagnostic accuracy and sensitivity for cholelithiasis exceeds 95%. In addition to detecting gallstones, information is provided concerning the size and shape of the gallbladder, gallbladder wall thickness, presence of pericholcystic fluid, or a sonographic Murphy’s sign. The latter has been suggested to have an 85% accuracy rate in patients with acute cholecystitis. Nonetheless, while abdominal sonography is most helpful in identifying the presence or absence of gallstones, it is of limited use in distinguishing chronic from acute cholecystitis. Hepatobiliary scintigraphy provides information on the patency of the bile ducts, including the cystic duct. Recognition that cystic duct obstruction is the sine qua non of acute cholecystitis, failure of the gallbladder to visualize during hepatobiliary scintigraphy is highly suggestive of acute cholecystitis. Although a number of false positive exams can occur, nonvisualization of the gallbladder during hepatobiliary scanning in the appropriate clinical setting is highly diagnostic of acute cholecystitis.