Biliary ultrasound: Difference between revisions

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==Video==
==Video==
===Normal Gallbladder in Sagittal Plane===
===Normal Gallbladder===
====Normal Gallbladder in Sagittal Plane====
[[File:NormalGBSagittal.gif]]
[[File:NormalGBSagittal.gif]]


===Normal Gallbladder in Transverse Plane===
====Normal Gallbladder in Transverse Plane====
[[File:Normal GB in Tranverse.gif]]
[[File:Normal GB in Tranverse.gif]]



Revision as of 21:32, 7 April 2016

Technique

  • Can use phased array or curvilinear probe
  • Look in midclavicular line at Right 11th/12th intercostal spaces or scan anteriorly from Morrison's pouch
  • Patient in Left lateral decubitus (if can tolerate)
    • Allow for better visualization of gallbladder (moves gallbladder anteriorly)
    • Better visualization of gallstones

Landmarks

  • Liver - used as a viewing window
  • Exclamation Point Sign: portal vein and medial longitudinal fasciculus (MLF)

Anatomy & Pathophysiology

  • Gallstones are classified as cholesterol stones and pigmented stones (black and brown), and are present in approx 20% of females and 8% of males in the United States
  • These stones cause the majority of all biliary tract problems, and depending on where the stone become impacted, specific problems occur.
  • Bile flows out the gallbladder, down the cystic duct into the common bile duct, and ultimately into the 1st portion of the duodenum.

Findings

Evaluate gallbladder for:

  1. GB wall measurement
  2. Pericholecystic free fluid
  3. Gallstones
  4. Common Bile Duct (CBD) measurement
  5. Sonographic Murphy's (pain with ultrasound probe palpation over gallbladder)

Measurements

  • GB wall is <4 mm
    • Measure the anterior wall at narrowest point with a short-axis view
    • Causes:
      • 1. Acute cholecystitis
      • 2. Ascites
      • 3. CHF
  • Gallstones
    • identify by hypoechoic "shadowing" behind hyperechoic stones
      • if no shadowing, may be polyps, sludge, etc.
    • SIN Sign: Stone-in Neck
  • Common Bile Duct
    • Measure from inner to inner
    • Normal is up to 4 mm to age 40 (add 1mm per decade thereafter)
    • Mickey Mouse Sign: Portal Vein (face), CBD (right ear), and hepatic artery (left ear)
      • Color doppler will demonstrate the vein and artery
  • Acalculous cholecystitis
    • GB is >10cm long & >4 cm wide

Pitfalls

  • Easily confused with duodenum: look for peristalsis
  • Contracted GB: three distinct wall layers is no pathological
  • GB Polyp: soft tissue masses attached to the wall of the gallbladder and differentiated from gallstones by their lack of mobility and shadowing
  • Renal Cyst: cysts in the superior pole of the kidney; get two views
  • Ascitic fluid: located throughout peritoneum, including Morrison’s pouch. Pericholecystic fluid is localized to the anterior side of the gallbladder

Video

Normal Gallbladder

Normal Gallbladder in Sagittal Plane

NormalGBSagittal.gif

Normal Gallbladder in Transverse Plane

Normal GB in Tranverse.gif

See Also

Source

Sonoguide