Predictors of appendicitis on computed tomography among cases with borderline appendix size

Area of Science:

• Radiology
• Medical Imaging
• Gastrointestinal Imaging

Background:

• Accurate diagnosis of appendicitis is crucial for timely treatment.
• Borderline appendix diameter (6-7 mm) on computed tomography (CT) poses diagnostic challenges.
• Identifying specific CT findings predictive of appendicitis in these cases is essential.

Purpose of the Study:

• To identify computed tomography (CT) findings most predictive of appendicitis in cases with a borderline appendix diameter.
• To evaluate the diagnostic performance of specific CT features for appendicitis.

Main Methods:

• Retrospective review of 105 contrast-enhanced CT scans with borderline appendices by three radiologists.
• Confirmation of appendicitis presence or absence via chart review of clinical or surgical outcomes.
• Logistic regression analysis to determine odds ratios (OR) and receiver operating characteristic (ROC) for CT features.

Main Results:

• Univariate analysis identified absence of intraluminal air (OR=5.11), wall hyperemia (OR=3.92), wall thickening (OR=29.7), and fat stranding (OR=3.85) as significant predictors.
• Multivariate analysis revealed absence of intraluminal air (OR=6.04) and wall thickening (OR=24.6) as statistically significant predictors, independent of gender and pediatric age.
• The combination of wall thickening and absence of intraluminal air demonstrated 92.6% sensitivity and 82.4% specificity for appendicitis.

Conclusions:

• Wall thickening and absence of intraluminal air are prominent predictors of appendicitis in borderline cases.
• The presence of both wall thickening and absence of intraluminal air can significantly aid in the CT diagnosis of appendicitis when the appendix diameter is borderline.
• A multivariate model incorporating these features improved diagnostic performance compared to initial clinical CT impressions.