Difference in Detection Rate of Portal Venous Gas via Computed Tomography and Ultrasonography in Pediatric Patients

This study was performed to compare computed tomography (CT)- and ultrasonography (US)-derived detection rates of portal venous gas (PVG) in pediatric patients and investigate whether discrepancies between these modalities were influenced by patient age and interval between examinations. We included 25 children who underwent both CT and US within 2 days for evaluation of intestinal ischemia. McNemar test was used to compare the detection of PVG between the 2 modalities. The cohort was retrospectively divided into 2 groups based on whether comparable results were obtained via both modalities; the Mann-Whitney U test was used to compare patient age and interval between CT and US between these 2 groups. Among 25 children, CT and US yielded similar results in 17 patients regarding the presence or absence of PVG (median age/interval, 2 years [range, 0-17 years]/51 minutes [range, 2-1196 minutes]; 3/14 detected via both/not both modalities) and different results in 8 (median age/interval, 0 years [range, 0-15 years]/171.5 minutes [range, 64-1486 minutes]; 7/1 detected via US only/via CT only). There was a significant difference in PVG detection rate between US and CT (P = 0.034). Patient age did not differ significantly between the 2 groups (P = 0.206), but the interval between CT and US did (P = 0.025). In conclusion, the detection rate of PVG was higher with US, compared with CT, although the timings of the examinations could have influenced this finding. Ultrasonography could be useful for PVG detection in pediatric patients because it can be performed repeatedly at the bedside without radiation exposure.