MRI an effective first step for imaging young patients with suspected acute appendicitis

MRI provides value as an initial imaging technique for pediatric patients with suspected acute appendicitis, according to a new study published in Radiology.

Ultrasound (US) is typically the initial imaging modality providers use for pediatric patients for suspected acute appendicitis. The study’s authors explained, however, that there are disadvantages to US, including “dependence on operator skills, limited evaluation for alternative diagnoses and complications and low negative predictive value.” When US isn’t getting the job done, the next step is frequently CT, but that has its own shortcomings.

“The use of CT in the pediatric population has been questioned and moderated because of concerns over the potential negative effects of ionizing radiation and the potential need for oral and/or intravenous contrast material,” wrote Raza Mushtaq, MD, department of medical imaging at the University of Arizona College of Medicine, and colleagues. “MRI overcomes these shortcomings of CT. Advances in MRI have enabled rapid, free-breathing imaging without the need for intravenous or oral contrast material, allowing for a more efficient, comprehensive evaluation of symptom etiology, which may be especially challenging to elicit clinically in a pediatric population.”

If unenhanced MRI can work as a second-line imaging modality for suspected acute appendicitis, could it be an effective first-line modality? That’s exactly what the researchers wanted to find out.

Mushtaq and colleagues studied more than 400 patients 18 years old or younger who presented with acute abdominal pain at a single institution from January 2013 to June 2016. Unenhanced MRI was the initial imaging modality for these patients. Overall, the team found that MRI as a primary diagnostic imaging modality for these patients had a sensitivity of 97.9 percent a specificity of 99 percent and an accuracy of 98.8 percent. The appendix was visualized in 86.8 percent of patients.

“The diagnostic performance and efficiency of current MRI may yield overall value when it is used as a first-line modality in pediatric ED for acute abdominal pain,” the authors wrote. “Real-world testing of unenhanced MRI at an academic center can yield results that are as good or better than those of US for the diagnosis of acute appendicitis and that are also favorable for identification of the appendix and for the evaluation of other causes of abdominal pain.”