Ultrasound is gaining favor as a radiation free tool for evaluating appendicitis. However, we are all faced with a challenge when the ultrasound is unable to visualize the appendix. What is the next step? Do we CT these kids? Observe them? MRI them? Admit to surgery? Certainly some of these decisions are made by the institution where you practice, but one study looked at the clinical outcomes in kids where the "appendix was not fully visualized."
-Retrospective chart review in a tertiary Canadian hospital of kids 2-17 who had US for suspected appendicitis (968 pts)
-526 kids had incompletely visualized appendices:
55 went to the OR
160 were observed
-105 were discharged home with no return visits
- 55 had appendectomies
-39 had appendicitis confirmed by pathology
-311 went home
58 bounced-back
1 had appendicitis confirmed by pathology
-442 kids had fully visualized appendices
232 were consistent with appendicitis
Bottom line: 15% of kids with an incompletely visualized appendix have appendicitis, so serial reexamination is imperative. If repeat clinical exams are reassuring, then the miss rate (for this study) was <0.3%.
References
Ross MJ, Liu H, Netherton SJ, Eccles R, Chen PW, Boag G, Morrison E, and GC Thompson. Outcomes of Children With Suspected Appendicitis and Incompletely Visualized Appendix on Ultrasound. Acad Emerg Med. 2014 May;21(5):538-542.
