Is Unenhanced Abdominal CT Scan Necessary for the Diagnosis of Acute Appendicitis in Children?

Abstract

Purpose: This study was designed to evaluate the questionof whether a computed tomography (CT) protocol withoutan unenhanced phase could be used for diagnosis ofappendicitis in pediatric patients who visited the emergencydepartment (ED) with acute non-traumatic right lowerabdominal pain.

Methods: We retrospectively selected 100 samples frompediatric abdominal CT scans performed in the ED andread by pediatric radiologists. Thirty emergency physicianswere separately asked to evaluate the samples twice. Thefirst evaluation was performed without the unenhancedphase (protocol A). The second evaluation was performedwith both the unenhanced phase and the contrastenhancedphase (protocol B). The sensitivity and specificityof each protocol for diagnosis of suspected acute appendicitiswere determined. Intraobserver and interobserveragreements were measured using kappa statistics.

Results: The mean sensitivity and specificity of the two protocolswere similar. The sensitivities of protocol A and protocolB were 97.13% (95% Confidence interval=96.13-98.14) and 97.60% (96.67-98.53), respectively. The specificitiesof protocol A and protocol B were 95.47% (94.34-96.59) and 94.67% (93.33-96.00), respectively. The meankappa value for intraobserver agreement between resultsfrom the two protocols was 0.91 (0.88-0.93). The kappavalue for interobserver agreement was 0.90 (0.89-0.91) forprotocol A and 0.87 (0.86-0.88) for protocol B.

Conclusion: It is feasible to perform a CT scan without anunenhanced phase for evaluation of suspected appendicitisin children with abdominal pain visiting the ED.