Accuracy of Point-of-Care Ultrasound for Diagnosis of Skull Fractures in Children

Abstract

To determine the test performance characteristics for point-of-care ultrasound performed by clinicians compared with computed tomography (CT) diagnosis of skull fractures. We conducted a prospective study in a convenience sample of patients ≤21 years of age who presented to the emergency department with head injuries or suspected skull fractures that required CT scan evaluation. After a 1-hour, focused ultrasound training session, clinicians performed ultrasound examinations to evaluate patients for skull fractures. CT scan interpretations by attending radiologists were the reference standard for this study. Point-of-care ultrasound scans were reviewed by an experienced sonologist to evaluate interobserver agreement. Point-of-care ultrasound was performed by 17 clinicians in 69 subjects with suspected skull fractures. The patients' mean age was 6.4 years (SD: 6.2 years), and 65% of patients were male. The prevalence of fracture was 12% (n = 8). Point-of-care ultrasound for skull fracture had a sensitivity of 88% (95% confidence interval [CI]: 53%-98%), a specificity of 97% (95% CI: 89%-99%), a positive likelihood ratio of 27 (95% CI: 7-107), and a negative likelihood ratio of 0.13 (95% CI: 0.02-0.81). The only false-negative ultrasound scan was due to a skull fracture not directly under a scalp hematoma, but rather adjacent to it. The κ for interobserver agreement was 0.86 (95% CI: 0.67-1.0). Clinicians with focused ultrasound training were able to diagnose skull fractures in children with high specificity.