Pediatric liver transplantation has evolved into a life-saving procedure since the first successful transplant, for biliary atresia, in 1967. In the United States, biliary atresia remains the leading indication, accounting for nearly half of all pediatric liver transplants, with most recipients aged five years or younger. Advances in surgical techniques, particularly the development of split-liver and living-donor transplantation, have significantly improved graft availability and patient survival, achieving one-year survival rates as high as 94%. Despite these advances, post-transplant complications remain common and are broadly categorized as vascular, biliary, infectious, and parenchymal or neoplastic. Vascular complications pose the greatest threat to graft viability. Early postoperative imaging surveillance with grayscale and Doppler ultrasound is vital for timely detection. Normal early postoperative findings include mild perihepatic fluid, subtle vascular narrowing, and heterogeneous parenchymal echotexture. Typical Doppler characteristics include brisk systolic upstroke with continuous diastolic flow in the hepatic artery, monophasic flow in portal vein, and multiphasic or dampened venous waveforms. Hepatic artery thrombosis is the most critical vascular complication, often manifested as tardus-parvus arterial waveforms, and can lead to graft ischemia or failure. Hepatic artery stenosis, occurring most often within the first 100 days, may require prompt endovascular intervention. Portal vein thrombosis or stenosis, though less frequent, can cause portal hypertension with splenomegaly and ascites. Biliary complications, including anastomotic strictures and leaks, affect approximately 12–40% of pediatric recipients, usually within the first three months post-transplant. In the longer term, neoplastic complications such as post-transplant lymphoproliferative disorder occur in up to 2-8%of pediatric liver transplant patients, necessitating vigilant radiologic and clinical follow-up. Ultrasound remains the cornerstone of early and serial postoperative evaluation, given its safety, accessibility, and high sensitivity for vascular and biliary pathology. Rapid identification of complications enables timely intervention, optimizing graft function and long-term survival in pediatric liver transplant recipients. Read More

Meeting name: SPR 2026 Annual Meeting , 2026

Authors: Kumar Tushar, Noda Sakura, Kim Helen Hr

Keywords: Hepatic Transplant, Transplant Interventions, Ultrasonography

Sinusoidal obstruction syndrome (SOS), also known as veno-occlusive disease (VOD), is a potentially life-threatening hepatic complication that occurs primarily following hematopoietic stem cell transplantation (HSCT). It is characterized by obstruction of hepatic sinusoids and venules due to accumulation of cellular debris and red blood cells, leading to impaired hepatic outflow. The incidence in pediatric patients can be as high as 40%, resulting from toxic injury or activation of liver sinusoidal endothelial cells (LSECs). Common etiologic factors include myeloablative conditioning regimens for HSCT, chemotherapeutic agents such as oxaliplatin, and total body irradiation. SOS/VOD is classified into acute (80%, within 21 days post-HSCT) and late-onset forms (20%, beyond 21 days). Histopathologically, late-phase SOS shows peri-sinusoidal fibrosis and hepatocyte atrophy in addition to sinusoidal obstruction. Clinically, the disease manifests with painful hepatomegaly, conjugated hyperbilirubinemia, and rapid weight gain or ascites. While the modified Seattle and Baltimore criteria are traditionally used for adults, the European Society for Blood and Marrow Transplantation (EBMT) 2019 criteria have been specifically developed for the pediatric population, incorporating both clinical and radiologic parameters. Ultrasonography remains the first-line imaging modality, including gray-scale, color Doppler, and spectral analysis. Ultrasound elastography can detect SOS as early as 2–12 days before clinical criteria are met by quantifying increased hepatic stiffness due to portal hypertension; a ≥ 30% rise in stiffness from baseline has demonstrated high sensitivity and specificity. Characteristic sonographic findings include hepatomegaly, gallbladder wall thickening, increased portal vein diameter, ascites, paraumbilical vein visualization with altered flow, reduced portal venous velocity, and elevated hepatic artery resistive index—imaging parameters that are incorporated into the newer Hok-US scoring system (maximum 14 points). Additionally, MR elastography and hepatobiliary MRI using Eovist have shown promise for early, noninvasive detection. Early diagnosis is critical, as severe SOS carries mortality rates up to 80%, and the only approved therapy remains defibrotide, emphasizing the need for vigilant imaging surveillance and prompt management. Read More

Meeting name: SPR 2026 Annual Meeting , 2026

Authors: Kumar Tushar, Elhussein Wala, Kim Helen Hr

Keywords: Abdominal Imaging, Venoocclusive Disease, Sinusoidal Obstruction Syndrome

To understand pediatric radiologists’ attitudes toward climate change, perception of patient impacts, knowledge of the impact of health systems on global warming, and beliefs on the role of health systems in mitigating climate change impact. The secondary purpose was to understand geographic or generational differences. Read More

Meeting name: SPR 2026 Annual Meeting , 2026

Authors: Walsh Caroline, Leschied Jessica, Mehollin-ray Amy Robben, Riedesel Erica, Kim Helen Hr

Keywords: Education, Survey, Healthcare Policy

Pediatric head CT examinations remain a mainstay imaging modality, frequently utilized to evaluate a wide spectrum of pediatric pathology. Current pediatric head CT protocols aim to use the least amount of radiation while providing imaging of diagnostic quality. Lower radiation doses, along with other factors, can occasionally cause CT artifacts that can affect the quality and the interpretation of images. In this exhibit, we review examples of physics-based, patient-based and scanner-based CT artifacts on head CT exams, while also providing a brief explanation of the underlying physics and ways to mitigate the artifact. Imaging examples include among others: apparent posterior fossa masses due to beam hardening, apparent extra-axial fluid collections due to cupping artifact, apparent brain parenchymal hypodensities concerning for infarct, and apparent beading of intracranial vessels due to lower radiation doses administered. Awareness of these artifacts is critical for radiologists, as they can potentially lead to misdiagnosis. Read More

Meeting name: SPR 2023 Annual Meeting & Postgraduate Course , 2023

Authors: Otjen Jeffrey, Phillips Grace, Khatri Garvit, Kanal Kalpana, Kim Helen Hr, Stanescu A. Luana

Keywords: Artifacts, CT, Head