Case #13: RUQ Pain
Katie Johns, M.D.

HPI: 49 year old female with PMH of morbid obesity, diverticulosis who presents with 3 days of constant RUQ abdominal pain which was exacerbated with eating and associated with nausea. No vomiting.

Physical Exam: Abdomen: +RUQ tenderness, +Murphy's sign, no guarding, rigidity, or rebound tenderness.

Bedside Ultrasound:

What structures do you see?

This is a transverse view of the gallbladder which shows gallstones as well as wall thickening (remember, the wall should be <4mm).
In order to complete our RUQ ultrasound we need to evaluate the common bile duct...

What structures do you see here?

How do you find this view?

Look for the "Mickey Mouse" sign of the portal triad (hepatic artery, common bile duct and portal vein) in the short axis, then rotate the probe 90 degrees into the long axis. This allows you to better evaluate the common bile duct for evidence of stones or strictures along its tract.

What if I am unsure which structure is the portal vein and which is the common bile duct?

You can use the doppler flow to help you determine which structure is your common bile duct and which is your portal vein, as the vein will have doppler flow and the CBD will not.

Is this patient's common bile duct dilated?

The rule of thumb is that the CBD diameter should be approximately 4mm or less. However remember that the CBD dilates as we age, so don't forget to use the correction factor of +1mm for every decade over 40.

This patient is 49 years old, so for her: CBD of 7.4mm = YES, her CBD is dilated.

Additional Resources:
http://www.emcurious.com/blog-1/2014/12/29/ultrasound-leadership-academy-ruq-ultrasound
https://www.acep.org/sonoguide/biliary.html