The positive and negative predictive value of transabdominal color Doppler ultrasound for diagnosing ovarian torsion in pediatric patients

Abstract

PurposeThe purposes of this study were to (1) determine the positive and negative predictive value (NPV) of transabdominal color Doppler ultrasound (CDU) for diagnosing ovarian torsion (OT) in pediatric patients and 2) identify predictors of a false-positive CDU result for OT. MethodsAn IRB-approved retrospective chart review was performed on all female patients who underwent transabdominal CDU evaluation of the ovaries (664 CDUs in 605 patients) for acute abdominal pain. CDU reports were categorized as positive for OT if the report stated “cannot rule out torsion” or “positive for torsion.” ResultsThere were 47 false-positive ultrasounds, 3 false negatives, 11 true positives, and 603 true negatives for OT. Sensitivity was 78.6%, specificity 92.3%, positive predictive value (PPV) 19.0%, and NPV 99.5%. False-positive CDU when compared to true positives were more common in older patients (p=0.004) and were more commonly read as “cannot rule out torsion” (p<0.001). Ovarian cysts were larger in true-positive CDU than in false-positive CDU (p<0.001). However, cyst presence/absence did not predict a true positive result. ConclusionTransabdominal CDU has a low PPV and a high NPV for ovarian torsion in pediatric patients. False-positive results are more common in older patients and associated with small ovarian cysts.