Purpose or Case Report: Pediatric acute appendicitis is the most common surgically treated disease in the United States. Evaluation via ultrasonography is recommended as the most appropriate initial modality to diagnose acute appendicitis in the pediatric population by the American College of Radiology. However, nonvisualization of the appendix creates diagnostic challenges leading to additional imaging and laboratory studies as well as costs. The purpose of this study is to determine the value of identifying the ileocecal valve as a reliable initial landmark for identification of the appendix via ultrasonography.
Methods & Materials: A retrospective review of 201 appendix ultrasounds obtained between November 2023 and August 2024 was performed. Studies demonstrating poor image quality, studies reinterpreted for outside institutions, and studies positive for acute appendicitis studies were excluded. Three radiologists reviewed these 201 studies independently to determine whether there was identification of the ileocecal valve and appendix, respectively. Their confidence levels were scored for identification of the ileocecal valve and appendix on a 4-point scale (1: Extremely Unconfident to 4: Extremely Confident). Data were analyzed by way of binomial generalized estimating equations.
Results: For all readers, the appendix identification probability ratios in which the ileocecal valve was identified were significantly higher than those in which the ileocecal valve was not identified (for reader 1; 1.85, 95%CI: [1.46, 2.09], p<0.001, reader 2; 1.45, 95%CI: [1.19,1.76], p<0.001 and reader 3; 1.67, 95% CI: [1.34,2.09], p<0.001). After adjusting for ileocecal valve and appendix reader identification confidence levels, the identification probability ratios were: 1.62, 95%CI: [1.43,1.84], p<0.001; 1.41, 95%CI: [1.12,1.78], p=0.004; and 1.75, 95% CI: 1.42-2.18, p<0.001 for readers 1, 2, and 3, respectively.
Conclusions: Identification of the ileocecal valve on sonography positively correlates with successful identification of the appendix.