The Utility of Ultrasound in Detecting Skull Fractures After Pediatric Blunt Head Trauma: Systematic Review and Meta-Analysis.

BACKGROUND

Head trauma is a common reason for evaluation in the emergency department. The evaluation for traumatic brain injury involves computed tomography, exposing children to ionizing radiation. Skull fractures are associated with intracranial bleed. Point-of-care ultrasound (POCUS) can diagnose skull fractures.

OBJECTIVES

We performed a systematic review/meta-analysis to determine operating characteristics of POCUS skull studies in the diagnosis of fractures in pediatric head trauma patients.

METHODS

We searched PubMed, EMBASE, and Web of Science for studies of emergency department pediatric head trauma patients. Quality Assessment Tool for Diagnostic Accuracy Studies 2 was used to evaluate risk of bias. Point-of-care ultrasound skull study operating characteristics were calculated and pooled using Meta-DiSc.

RESULTS

Six studies of 393 patients were selected with a weighted prevalence of 30.84%. Most studies were at low risk of bias. The pooled sensitivity (91%) and specificity (96%) resulted in pooled positive likelihood ratio (14.4) and negative likelihood ratio (0.14). Using the weighted prevalence of skull fractures across the studies as a pretest probability (31%), a positive skull ultrasound would increase the probability to 87%, whereas a negative test would decrease the probability of a skull fracture to 6%. To achieve a posttest probability of a skull fracture of ~2% would require a negative skull ultrasound in a patient with only a pretest probability of ~15%.

CONCLUSIONS

A POCUS skull study significantly increases the probability of skull fracture, whereas a negative study markedly decreases the probability if the pretest probability is very low.