Résumé
Purpose: To identify factors associated with false or indeterminate US result for suspected appendicitis, and assess whether multi-categorical reporting of US yields more precise estimates regarding the probability of appendicitis. Methods: 562 US examinations for suspected appendicitis between May 2013-April 2015 were categorized as true (77/562 true positives or true negatives) or false/indeterminate (485/562 false negatives, false positives or indeterminates) based on results from a prior study. Of 541 examinations with images available retrospectively, a category of A–E was assigned as follows: non-visualized appendix with secondary findings (A) absent or (B) present; appendix visualized and considered (C) negative, (D) equivocal, or (E) positive for appendicitis. The following factors were recorded: age; sex; scan time (daytime vs. off-hours); resident/fellow involvement; abdominal subspecialty radiologist; radiologist experience (>5 years or not); and tenderness on interrogation. Associations between factors and US result were assessed (t-tests, Fisher's exact test and multivariate logistic regression). Results: The true group had proportionally more males (18/77 (23.4%) vs. 66/485 (13.6%), p = 0.04) and patients with sonographic tenderness (43/77 (55.8%) vs. 132/353 (27.3%), p < 0.0001). There was no significant difference or association with other factors. On multivariate logistic regression, false/indeterminate results were 1.9 times (95% CIs 1.0–3.5) more likely among females and 3.8 times more likely in the absence of tenderness (95% CIs 2.3–6.4). The proportion of patients with appendicitis in categories A-E was 34/410 (8.3%), 24/44 (54.5%), 0/18 (0%), 0/3 (0%) and 61/66 (92.4%), respectively. Conclusions: Females and absence of tenderness were associated with a false/indeterminate US. Categorical reporting provides more granular estimates of the post-test probability of appendicitis.
Langue d'origine | English |
---|---|
Numéro d'article | 109992 |
Journal | European Journal of Radiology |
Volume | 144 |
DOI | |
Statut de publication | Published - nov. 2021 |
Publié à l'externe | Oui |
Note bibliographique
Funding Information:The authors thank Dorrell Metcalfe for assistance with retrieval of imaging examinations, and J Byron Ramsey and M Kamali for assistance with data collection.
Publisher Copyright:
© 2021 Elsevier B.V.
ASJC Scopus Subject Areas
- Radiology Nuclear Medicine and imaging
PubMed: MeSH publication types
- Journal Article