Chronic Inflammatory Appendiceal Conditions That Mimic Acute Appendicitis on Helical CT

OBJECTIVE: Acute appendicitis is commonly diagnosed on CT, but chronic appendiceal processes can mimic acute appendicitis. The purpose of this study was to identify the frequency of these alternative conditions and their findings on helical CT. CONCLUSION: Chronic inflammatory conditions other than acute appendicitis were found in 9% of patients who underwent surgery after CT findings were interpreted as suspicious for appendicitis. These inflammatory conditions were indistinguishable from acute appendicitis when we used either primary or secondary CT signs.