Case contributed by Toronto RadCases
Unlisted case: This is an unlisted case only visible to the author and the editorial team. Unlisted cases can still be shared with individuals or with members of your verified institution.


Right lower quadrant pain


The appendix is fluid filled, thick with hyperenhancing walls, and periappendiceal stranding.

Case Discussion

  • Findings: The appendix is fluid filled and thick with hyperenhancing walls, periappendiceal stranding, appendicolith

  • Objectives:

    • To review the anatomy of the appendix and how to identify it on CT

    • To review the CT signs of uncomplicated appendicitis

    • To review the complications of appendicitis and their imaging appearance

  • Protocolling:

    • Contrast vs non-contrast CT – discuss oral and IV contrast use

  • Key Points:

    • Identifying the appendix on CT:

      • Follow the colon from the rectum to the cecum

      • Identify the ileo-cecal valve (sail sign, fat density)

      • Appendix should arise from the cecum DISTAL (not necessarily inferior) to the IC valve, AND from the same side of the cecum as the IC valve

    • CT signs of uncomplicated appendicitis

      • Dilated appendix (>7mm)

      • Hyper-enhancing, thick appendix wall

      • Focal cecal thickening (cecal bar sign, arrow sign)

      • Periappendiceal stranding

      • Appendicolith

    • Complications to look for:

      • Perforation - extraluminal gas, discontinuous wall, fluid collection

      • Abscess (in the setting of perforation)

      • Thrombosis of portal venous system (SMV, portal vein)

      • Hepatic abscess

      • Fistula

  • Differential diagnosis:

    • Tumors of the appendix

    • Chronic appendicitis, as in Crohn appendicitis

How to use cases

You can use Radiopaedia cases in a variety of ways to help you learn and teach.

Creating your own cases is easy.

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.