Ultrasonography of the biliary tract
The biliary tract is sometimes best evaluated in the intercostal space (between the ribs), and sometimes in the upper right abdominal quadrant during inspiration (possibly with the patient turned to the right for gallbladder visualization). Thus, if one of the methods does not clearly rule out pathology, the other one should be done as well.
- Scan the entire gallbladder in both its axial and transverse plane, looking mainly for gallstones (see Ultrasonography of gallstones) and wall thickening (see Ultrasonography of thickened gallbladder wall).
- Measure the width of the bile ducts, which is usually easiest for the perihilar bile duct (which is the region where the common hepatic duct becomes the common bile duct, at the hilum of the liver). A normal width of the perihilar bile duct can be reported as for the extrahepatic bile ducts, since it also excludes a more distal common bile duct obstruction. The common bile duct is normally up to 8 mm. If dilated, see Ultrasonography of dilated bile ducts.
- Also take a look at intrahepatic bile ducts to rule out obvious dilation.
Doppler ultrasonography of dilated intrahepatic bile ducts, in this case because of pancreatic cancer. The bile ducts are colorless (black) in contrast to blood vessels (portal vein near center, and hepatic artery to the right of it) which have Doppler signal.
It is usually preferable to also perform a general upper abdominal screening.
Example in a normal case:
Gallbladder with thin wall and no gallstones. Normal width of the intra-and extrahepatic bile ducts.
- See also: General notes on reporting
- For a full list of contributors, see article Radlines:Authorship for details. . Creators of images are attributed at the image description pages, seen by clicking on the images. See
- Hoeffel, Christine; Azizi, Louisa; Lewin, Maité; Laurent, Valérie; Aubé, Christophe; Arrivé, Lionel; Tubiana, Jean-Michel (2006). "Normal and Pathologic Features of the Postoperative Biliary Tract at 3D MR Cholangiopancreatography and MR Imaging ". RadioGraphics 26 (6): 1603–1620. doi:10.1148/rg.266055730. ISSN 0271-5333.