Which of the following CT findings indicates a normal appendix?

Which of the following CT findings indicates a normal appendix?

• A. Appendix diameter of 8 mm
• B. Wall thickening with enhancement
• C. Wall enhancement after contrast
• D. Appendix wall less than 6 mm with no thickening or enhancement

Answer: (D)

A normal appendix on CT is small and noninflamed. The key feature is a thin wall with a diameter typically under 6 mm, and no thickening or enhancement after contrast. When the appendix is enlarged (around 8 mm) or shows wall thickening and enhancement, that points to inflammation such as appendicitis. Wall enhancement after contrast indicates inflamed mucosa, not a normal appendix. So the description of an appendix with a wall under 6 mm and no thickening or enhancement fits a normal appendix.

A normal appendix on CT is small and noninflamed. The key feature is a thin wall with a diameter typically under 6 mm, and no thickening or enhancement after contrast. When the appendix is enlarged (around 8 mm) or shows wall thickening and enhancement, that points to inflammation such as appendicitis. Wall enhancement after contrast indicates inflamed mucosa, not a normal appendix. So the description of an appendix with a wall under 6 mm and no thickening or enhancement fits a normal appendix.