Independent predictors of acute appendicitis on CT with pathologic correlation

Area of Science:

• Radiology
• Medical Imaging
• Gastrointestinal Imaging

Background:

• Appendicitis diagnosis relies on various computed tomographic (CT) signs.
• Identifying independent predictors of appendicitis is crucial for accurate diagnosis.

Purpose of the Study:

• To evaluate CT findings for appendicitis diagnosis.
• To identify independent CT signs that predict appendicitis.

Main Methods:

• Retrospective review of 67 patient CT scans with pathological correlation.
• Three blinded observers assessed specific CT features including appendix diameter, enhancement, and surrounding fat infiltration.

Main Results:

• Appendix diameter >8 mm (OR 34.8) and appendix enhancement (OR 4.4) were significant univariate predictors.
• Only appendix diameter and enhancement remained significant independent predictors on multivariate analysis.
• Appendix diameter alone (Az = 0.91) was more accurate than all secondary signs combined (Az = 0.80).

Conclusions:

• Appendix diameter is the single best CT criterion for appendicitis.
• An 8-9 mm cutoff balances sensitivity and specificity; a 6-7 mm cutoff prioritizes sensitivity.
• Appendiceal enhancement adds diagnostic value, but other secondary signs do not improve accuracy.