Although CT is accurate in the evaluation of suspected appendicitis in the pediatric population, ultrasound is nearly as good in experienced hands. Appendicitis may be diagnosed based on physical examination. If imaging is needed, ultrasound (including serial ultrasounds) are the preferred initial modality in children. If the results of the ultrasound exams are equivocal, it may be followed by CT. This approach reduces potential radiation risks and has excellent accuracy, with reported sensitivity and specificity of 94 percent.
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