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Case of the Week 361

What's the most likely diagnosis?

  • 61 year-old with abdominal pain

Axial CT scan of the pelvis at bone window settings

  1. Crohn's disease
  2. Bilateral pelvic fractures
  3. Ureteral calculi
  4. Intraosseous pneumatocysts
  5. Paget's disease

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4. Intraosseous Pneumatocysts



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Intraosseous Pneumatocysts

General Considerations

  • Almost always found in the ilium or sacrum, near the sacroiliac joint
    • Also in the spine, especially cervical spine associated with degenerative disease
  • Gas-containing
    • The gas is mostly nitrogen
  • Uncertain etiology
  • A communication with the joint is usually not visible

    More ...


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