Clinical Applications of Contrast-Enhanced Ultrasound in the Pediatric Work-Up of Focal Liver Lesions and Blunt Abdominal Trauma: A Systematic Review

Abstract

In pediatrics ultrasound has long been viewed more favorably than imaging that exposes patients to radiation and iodinated contrast or requires sedation. It is child-friendly and diagnostic capabilities have been improved with the advent of contrast-enhanced ultrasound (CEUS). The application of CEUS is indeed promising. However, no ultrasound contrast agent manufactured today is registered for pediatric use in Europe. The contrast agent SonoVue? has recently been approved by the FDA under the name of Lumason? to be used in hepatic investigations in adults and children. This article reviews the literature with respect to 2 specific applications of CEUS in children: 1) identification of parenchymal injuries following blunt abdominal trauma, and 2) classification of focal liver lesions. Applications were chosen through the CEUS guidelines published by the European Federation of Societies for Ultrasound in Medicine and Biology and World Federation for Ultrasound in Medicine and Biology. Literature was obtained by searching Medline and Pubmed Central (using Pubmed), Scopus database and Embase. CEUS proved to be an effective investigation in the hemodynamically stable child for identifying parenchymal injuries and for the characterization of focal liver lesions. CEUS showed comparable performance to CT and MRI with a specificity of 98% for identifying benign lesions and a negative predictive value of 100%. For the applications reviewed here, CEUS holds promising perspectives and can help reduce radiation exposure and use of iodinated contrast agents in pediatrics, thereby potentially reducing complications in routine imaging.

The AFSUMB Consensus Statements and Recommendations for the Clinical Practice of Contrast-Enhanced Ultrasound using Sonazoid

“…A residual viable tumor can be detected during the RFA session using CEUS. In addition, CEUS may allow visualization of immediate complications after RFA such as active bleeding, hemobilia, or segmental infarction of the liver [155]. For these reasons, CEUS may have the potential to reduce the number of CT examinations after RFA [156].…”

New Perspectives for Modern Trauma Management – Lessons Learned from 25 Years FAST and 15 Years E-FAST

“…A recent meta-analysis of nine studies comparing CEUS to contrast-enhanced CT in adult blunt trauma patients showed excellent sensitivity for CEUS of 0.981 (95 % CI: 0.868-0.950) and a false-positive rate of 0.018 (95 % CI: 0.010-0.032) for identifying parenchymal injuries [61]. The accuracy of CEUS in adult trauma patients is close to the sensitivity and specificity of contrast-enhanced CT. CEUS seems to be especially relevant for the up to 37 % of pediatric trauma patients that have abdominal parenchymal injuries verified on CT [62,63] but did not show evidence of free abdominal fluid on conventional B-mode ultrasound. Here, in addition to avoiding routine exposure to ionizing radiation and sedation for the CT exam, CEUS achieves excellent accuracy in identifying solid organ injuries that frequently present without free abdominal fluid and has shown comparable accuracy to that of contrast-enhanced CT [64].…”

Contrast-Enhanced Ultrasound and Near-Infrared Spectroscopy of the Neonatal Bowel: Novel, Bedside, Noninvasive, and Radiation-Free Imaging for Early Detection of Necrotizing Enterocolitis

“…The use of US with contrast is off label in pediatrics with the exception of investigation of focal liver lesions, approved by the Food and Drug Administration in 2016, and vesicoureteral reflux. 35 Off-label use is common in pediatrics given that many drugs are not separately tested in children. As long as US contrast is off label, it will require that parents and guardians be informed of the risk and benefits of contrast use and acquire informed consent before its use.…”