Evidence base for point-of-care ultrasound (POCUS) for diagnosis of skull fractures in children: a systematic review and meta-analysis

Abstract

BackgroundBlunt head trauma is a common presentation to emergency departments (EDs). Identifying skull fractures in children is important as they are known factor of risk for traumatic brain injury (TBI). Currently, CT is the reference standard for diagnosing skull fractures and TBIs in children. Identifying skull fractures with point-of-care ultrasound (POCUS) may help risk-stratify children for TBI following blunt trauma. The purpose of this study is to evaluate the sensitivity, specificity, positive predictive value and negative predictive value of POCUS in identifying skull fractures in children.MethodsA systematic search was performed on 17 July 2020 in Ovid Medline, Cochrane Library, Google Scholar, Web of Science and Embase. Prospective studies reporting skull fractures diagnosed with ultrasound in children younger than 18 years due to blunt head injury were included. Studies that did not confirm the fracture with CT were excluded. The quality of studies was evaluated using the QUADAS-2 tool. Data were extracted from the eligible studies to calculate outcomes such as sensitivity and specificity; when possible overall outcomes were calculated.ResultsSeven studies were included. All eligible studies included patients for whom the decision to perform a CT scan was made in advance. Overall, the included studies demonstrated low risk of bias or had minor concerns regarding risk of bias. The pooled data (n=925) demonstrated a sensitivity of 91%, specificity of 96%, positive predictive value of 88% and negative predictive value of 97%.ConclusionThe included studies demonstrate minor methodological limitations. Overall, the evidence suggests that POCUS is a valid option for diagnosing skull fractures in children visiting the ED after blunt head injury.

Non-ionizing Imaging for the Emergency Department Assessment of Pediatric Minor Head Trauma

“…Both included prospective studies that compared POCUS results with CT scan findings (reference standard). Both meta-analyses, although slightly different in the methods and in the number of studies included [six studies in Gordon et al ( 39 ) and seven in Alexandridis et al ( 38 )] found a pooled sensitivity of 91% and a pooled specificity of 96%, confirming the accuracy of POCUS in detecting skull fractures. Overall, the largest meta-analysis analyzed 925 patients, with study samples ranging from 21 to 538 patients and percentage of skull fractures on CT ranging from 10 to 77%.…”

“…In the context of pediatric MHT, this technique is particularly useful when a scalp hematoma is present and clinical signs of a palpable skull fracture may be unclear or doubtful to define the presence of an underlying depressed or complicated fracture of the skull ( 36 , 37 ). Two recent meta-analyses ( 38 , 39 ) evaluated the accuracy of skull POCUS performed by ED physicians in identifying skull fractures in children with head trauma. Both included prospective studies that compared POCUS results with CT scan findings (reference standard).…”

“…One of the limitations of US is the training required to achieve the ability to accurately identify disease, which makes this imaging modality operator-dependent. However, limited training is required to accurately identify skull fractures ( 38 ). A recent multicentre study showed that clinicians who were mostly novices to skull POCUS, were able to correctly classify the type of skull fracture as linear, depressed, or complex in 84.4% of cases as compared with CT scan results (k statistic of 0.75, 95% CI 0.70–0.84) ( 40 ).…”

Imaging of Bone in the Head and Neck Region, is There More Than CT?

“…The evidence for point of care ultrasound for the diagnosis of skull fractures in children has been recently reviewed in a systematic review and meta-analysis by Alexandridis et al [ 12 * *], who appraised 7 relevant studies. Sensitivity ranged from 67–100% and specificity from 85%-100%.…”

“…Frequently, point of care ultrasounds are performed by the resident clinical team, with wide variability in ultrasound experience and expertise. In the meta-analysis by Alexandridis et al [ 12 * *], ultrasounds were typically performed by clinicians after a training period of 1 h. This will contribute to the reported specificity of the various studies, with operators with the most experience and training invariably attaining the most accurate diagnoses.…”