Contrast-enhanced ultrasound in children: a first-of-its-kind comprehensive compendium!

Abstract

Innovation in diagnostic imaging and interventional radiology plays an important role in the advancement and optimization of the care of our patients. Contrast-enhanced ultrasound (CEUS) is performed with the administration of ultrasound contrast agents (UCAs) and can significantly improve the conspicuity of sonographic findings and the overall diagnostic capability of ultrasound (US). This supplementary edition of Pediatric Radiology is devoted to the detailed presentation ofCEUS, focused on its use in children. Contrast-enhanced US has a multitude of advantages for our pediatric patients. Adding UCA to an US examination can help avoid the use of CT or MRI and thus eliminate radiation exposure or sedation/anesthesia, respectively. Other notable benefits of CEUS are the child’s comfort and a positive family experience made possible by the relative ease of an US exam, including the ability to conduct the study at the bedside. The high safety profile of UCAs compared to other contrast agents, plus the fact that UCAs can be administered in children with reduced renal function, are additional important advantages of this imaging technique. However, the pivotal argument for adopting a pediatric CEUS service is diagnostic efficacy. The diagnostic value of CEUS can be comparable or even better than fluoroscopy, CT orMRI. Also, the use of UCAs allows for novel US applications that were not possible without contrast agents (e.g., intralymphatic administration), and therefore significantly widens the scope of US in children. Since the mid-1990s, UCAs have been used off-label in children, particularly in Europe. The main application was contrastenhanced voiding urosonography (ceVUS) for the detection of vesicoureteric reflux, and this application gradually spread to different countries in Europe. The real breakthrough for pediatric CEUS came in 2016, when the United States Food and Drug Administration (FDA) approved the first UCA for both intravenous and intravesical indications in children. This approval was followed by subsequent pediatric approvals in Europe andChina. There is no doubt that these approvals spurred the continued widespread clinical implementation of CEUS for children and prompted the expansion of pediatric CEUS research. Considering the increasing popularity of these onand offlabel applications of UCAs, it seemed timely to publish a supplemental edition of this journal dedicated to pediatric CEUS. This comprehensive compendium on pediatric CEUS has a fourfold purpose. The first is to present all aspects of current on-label UCA applications, which include the intravenous administration for evaluation of the liver and heart as well as the intravesical use for vesicoureteric reflux detection. The second objective is to provide a detailed discussion of all current off-label applications. These comprise not only the examination of organs that are not yet approved such as the brain, but also off-label routes of administration such as intralymphatic, as well as novel uses in interventional radiology. Third, the articles in this issue review relevant CEUS applications and results in adults to underscore the pediatric applications and suggest potential future uses that can be extrapolated from the experience in adults. Last, these articles discuss both emerging pediatric CEUS applications and potential future pediatric CEUS directions. Thus, this supplement affords a most complete perspective on pediatric CEUS in the truest sense, from head to toe! We cannot think of one current subject about CEUS relevant to pediatrics that is missing in this supplement. This supplemental edition is the result of a tremendous international collaboration. The work presented here spans more than 2 years, beginning in the pre-COVID (coronavirus disease 2019) era and struggling through the peak pandemic year 2020, but successfully emerging as planned in 2021. It covers all aspects of CEUS, with strong emphasis on pediatric CEUS in 22 publications by 205 authors. The contributions came from four continents (Asia, Europe, North America, South America) * Kassa Darge [email protected]