Context

Each year in the USA, approximately 110 000–120 000 children are treated for acute appendicitis. However, the number of children referred for imaging evaluation for suspected appendicitis is much higher. The clinical diagnosis can be challenging, especially in a young child or adolescent girl.

Over the last decade, the role of imaging in the evaluation of suspected appendicitis has become well established in adults and children. What remains unclear is which modality should be used under which circumstance. The ideal imaging test would be readily available, fast, inexpensive, reproducible and safe and would accurately distinguish children with appendicitis from those without the disease. Ultrasound fulfils many of these ideal characteristics. However, its biggest limitation is that a normal appendix must be visualised with a high degree of confidence in order to exclude appendicitis. Unfortunately, visualisation rates reported …