Ultrasound: Appendix
Indications
Anyone suspected of having Appendicitis with symptoms including RLQ pain, fever, nausea, vomiting.
Technique
- Use curvilinear probe or linear probe
- Scan RLQ from ASIS to R iliac artery to identify blind-ended, non-peristalsing tubular structure
- Once identified, evaluate if the tube is compressible in the transverse view
- Appendicitis = noncompressible tube >6mm
- Abdominal free fluid, wall edema, identification of fecalith are suggestive of appendicitis
Diagnosis
- Identification of a noncompressible, blind-ending tubular structure in the longitudinal axis
- Measures >6 mm in diameter (outer to outer)
- Lacks peristalsis
- Target-like appearance in the transverse axis
“Sensitivity & Specificity: In pediatrics the values are about 88% and 94% respectively, and in adults about 83% and 93%."
Support
The American Academy of Emergency Medicine American Academy of Emergency Medicine and The American College of Emergency Physicians have both put our policy statements supporting the use of ultrasound in the diagnosis of appendicitis. "AAEM It is the position of the American Academy of Emergency Medicine that when appropriate expertise is available ultrasonography (US) should be strongly considered as the initial imaging modality when evaluating the pediatric patient with suspected acute appendicitis who requires imaging." http://www.aaem.org/UserFiles/FinalBODApprvdfrWepPostUSPeds5713.pdf