Single institutional experience with initial ultrasound followed by computed tomography or magnetic resonance imaging for acute appendicitis in adults
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The objectives of this study was to assess the performance of ultrasound (US) for suspected appendicitis in adult patients and to evaluated the additive value of short-interval (within 1 week) computed tomography (CT) or Magnetic Resonance Imaging (MRI) after performing an initial US.
In this IRB-approved, HIPAA-compliant, retrospective study, electronic medical records (EMRs) were queried for “US appendicitis” performed over a 2-year interval. EMR was reviewed for CT or MRI performed within 1 week of this exam, and if any new or additional information was available at subsequent exam. White count, patient disposition, and pathology, if surgery was performed, were also recorded.
682 patients underwent US for appendicitis over a 2-year duration, age range from 18 to 92 years (average: 30.1 years, M:F = 141:541). Findings showed 126/682 patients with normal appendix, 75/682 uncomplicated appendicitis, and 4/682 with complicated appendicitis. When performed, no additional findings were seen in these groups on short-interval CT or MRI. 2/682 patients had equivocal findings on US but eventually had normal appendix identified on CT. Four hundred and seventy-three patients had non-visualized appendix, of which only 14/473 (3.1%) eventually had appendicitis.
Ultrasound is an effective initial modality for evaluating appendicitis even in adult patients. Once a normal appendix, uncomplicated or complicated appendicitis is identified on US, no further imaging is necessary. Very few patients with non-visualization of the appendix eventually have appendicitis. Hence, these patients can be managed with active clinical follow-up rather than immediate CT or MRI. Symptoms and clinical scoring systems can be used for triage of these patients.
KeywordsAppendicitis Adults Ultrasound Follow-up Computed tomography Initial ultrasound
- 1.Expert Panel on Gastrointestinal, I., et al., ACR Appropriateness Criteria((R)) Right Lower Quadrant Pain-Suspected Appendicitis. J Am Coll Radiol, 2018. 15(11S): p. S373–S387.Google Scholar
- 3.Ramsay, G., J.M. Wohlgemut, and J.O. Jansen, Emergency General Surgery in the United Kingdom: A lot of General, not many Emergencies, and not much Surgery. J Trauma Acute Care Surg, 2018. Sep;85(3):500–506Google Scholar
- 5.Chiu, Y.H., et al., Whether intravenous contrast is necessary for CT diagnosis of acute appendicitis in adult ED patients? Acad Radiol, 2013. 20(1): p. 73-8.Google Scholar
- 8.Doria, A.S., et al., US or CT for Diagnosis of Appendicitis in Children and Adults? A Meta-Analysis. Radiology, 2006. 241(1): p. 83-94.Google Scholar
- 15.Alzahrani, H., et al., Imaging Approach to the Diagnosis of Acute Appendicitis in a Group of Teaching Hospitals With 24/7 In-house Availability of Ultrasound Technologist: Effect of Timing of Request on Imaging Modality. Can Assoc Radiol J, 2018. Aug;69(3):311-315. https://doi.org/10.1016/j.carj.2018.03.002. Epub 2018 Jun 27.
- 17.Li, J., et al., Effect of Delay to Operation on Outcomes in Patients with Acute Appendicitis: a Systematic Review and Meta-analysis. J Gastrointest Surg, 2018. Jan;23(1):210-223. https://doi.org/10.1007/s11605-018-3866-y. Epub 2018 Jul 6.
- 19.Pelin, M., et al., Acute appendicitis: Factors associated with inconclusive ultrasound study and the need for additional computed tomography. Diagn Interv Imaging, 2018. Dec;99(12):809-814. https://doi.org/10.1016/j.diii.2018.07.004. Epub 2018 Sep 7.
- 24.Kelly, B.S., et al., Improving diagnostic accuracy in clinically ambiguous paediatric appendicitis: a retrospective review of ultrasound and pathology findings with focus on the non-visualised appendix. Br J Radiol, 2018: Sep 12:20180585. https://doi.org/10.1259/bjr.20180585. [Epub ahead of print]
- 25.Williamson, K., et al., Outcomes for Children With a Nonvisualized Appendix on Ultrasound. Pediatr Emerg Care, 2018. Nov 12. https://doi.org/10.1097/pec.0000000000001672. [Epub ahead of print]
- 27.Malia, L., et al., Diagnostic accuracy of laboratory and ultrasound findings in patients with a non-visualized appendix. Am J Emerg Med, 2018. Aug 7. pii: S0735-6757(18)30650-8. https://doi.org/10.1016/j.ajem.2018.08.014. [Epub ahead of print]
- 31.Corkum, K.S., et al., Absolute neutrophil count as a diagnostic guide for the use of MRI in the workup of suspected appendicitis in children. J Pediatr Surg, 2018. Jun 22. pii: S0022-3468(18)30397-X. https://doi.org/10.1016/j.jpedsurg.2018.06.021. [Epub ahead of print]