Positions and Sizes of Normal Appendix: Results from a Single Center

• Published in: Journal of Radiological Science 2024-06, Vol.49 (1), p.33-38
• Main Authors: Hon‑Man Liu, Wei‑Min Tsai
• Format: Article
• Language: English
• ISSN: 2521-3334
• DOI: 10.4103/jradiolsci.JRADIOLSCI-D-23-00023

Background: The purpose of this study was to assess the position and diameter of the appendix among the Taiwanese population using multi‑detector computed tomography (CT) at a single institute. Materials and Methods: We retrospectively reviewed the 4371 abdominal and pelvic cavity CT images taken between November 1, 2019, and July 31, 2020. We excluded patients with clinically suspected appendicitis. Images of poor quality, such as those with motion artifacts, were excluded. A result was recorded after consensus. The anatomical positions of the appendix were categorized as retrocecal, pelvic, subcecal, preileal, postileal, ectopic, or paracecal. Results: In total, 175 participants were included in the analysis. The distribution of normal appendiceal positions was as follows: subcecal in 58 (33.1%) patients, pelvic in 56 (32.0%), postileal in 45 (25.7%), retrocecal in 8 (4.6%), preileal in 5 (2.9%), ectopic in 3 (1.7%), and paracecal in 0 (0%). The average diameter of the appendix was 5.6 mm (mean: 2.5-7.2) with a standard deviation of 0.9 mm. There was no statistically significant difference between the male and female groups in appendiceal position and size in this study. Conclusion: The subcecal, pelvic, and ileal appendiceal positions were those most commonly identified in this study, which is consistent with most research. The definitions of the positions clearly affected the final results. The appendiceal mean diameter was 5.6 mm (2.5-7.2 mm) at CT.