Acute appendicitis is the most common disease of the appendix. However, the differential diagnosis for an abnormal appendix includes other conditions that often present with symptoms and imaging features that overlap with acute appendicitis. In this pictorial essay, we review the normal anatomy of the appendix and outline the pathogenesis, clinical manifestations, and imaging findings that are characteristic of acute appendicitis and other less common appendiceal abnormalities. Inflammatory/non-neoplastic processes including appendiceal diverticulitis, stump appendicitis, foreign body appendicitis, Crohn’s appendicitis, and appendiceal hernias are discussed. Neoplastic considerations include appendiceal neuroendocrine tumors, mucinous and non-mucinous (colonic type) epithelial neoplasms, and lymphoma. It is important for the radiologist to be able to differentiate these alternative diagnoses for the purpose of directing appropriate patient management.
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Drawings courtesy of Jennifer Armstrong, Medical Illustrator, Faculty of Medicine, Memorial University of Newfoundland.
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The authors declare that they have no conflict of interest.
This study was approved by the Health Research Ethics Board at Memorial University.
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Fenwick, A.K., Hartery, A. Appendicitis and beyond: a pictorial review of various appendiceal abnormalities. Emerg Radiol (2021). https://doi.org/10.1007/s10140-021-01908-3
- Gastrointestinal tract
- Appendiceal neoplasm