Clinical Indication

RUQ abdominal pain, epigastric pain, back pain, cholestatic labs

Probe Selection

Curvilinear or Sector (aka Cardiac) 

Additional Views and Measurements

  • Comment on presence or absence of sonographic Murphy’s sign
  • Use color doppler to demonstrate the absence of flow in the CBD
  • Measure the GB itself (dilation can be a sign of an obstructing stone that you can’t visualize, called Hydrops)

Tips

  • If you are having difficulty finding the GB try the following techniques: 
    • Have the patient take a deep breath and hold it to move the GB below the ribs
    • Place the patient left lateral decubitus position to shift bowel gas out of view
    • Ask the patient if they recently ate – if so the GB may be contracted
    • Ask the patient if they have had a cholecystectomy
  • To find the CBD, first locate the porta hepatis and then rotate the probe so the structures are in longitudinal view. Use color doppler mode to find the structure with no flow (i.e. CBD) - it usually rests anterior to or on top of the portal vein. You may see 3 tubes (parallel channel sign) which are from top to bottom: the CBD, portal vein and IVC.
  • GB polyps may mimic a stone in appearance, but polyps won’t shadow like stones. Have the patient lay in left lateral decubitus and see if the stone falls into the most dependent part of the GB, if it remains in place, it is more likely a polyp.
  • Do not mistake “Edge Artifact” for a stone, conversely a stone at the neck of the GB may look like edge artifact.
  • Look for a WES sign or “wall-echo-shadow” which is a shadow created by a single large stone filling the GB causing extensive shadowing. 
  • A thickened anterior GB wall may be due to a post-prandial state, a viral infection or a cirrhotic liver. Look to see if the wall is symmetrically contracted which is indicative of a post-prandial GB. If layering of the GB wall is present, aka “Onion-skinning” this is more suggestive of an acutely inflamed GB as in cholecyctitis.