Consensus Minimum MRI Protocol for the Child With Acute Recurrent or Chronic Pancreatitis.

Imaging plays an important role in the diagnosis and follow-up of children with acute recurrent pancreatitis (ARP) and chronic pancreatitis (CP). Consensus is lacking for a minimum MRI protocol for the child with known or suspected ARP or CP. Lack of standardization contributes to variable diagnostic performance and hampers application of uniform interpretive criteria for clinical diagnosis and multicenter research studies. We convened a working group to achieve consensus for a minimum MRI protocol for children with suspected ARP or CP. The group included eight pediatric radiologists experienced in interpreting MRI for pediatric pancreatitis and one medical pancreatologist and functioned from November 2022 to March 2023. Existing clinical protocols were summarized across sites represented by group members, and commonly used sequences guided the group's discussion. The final consensus minimum MRI protocol includes five noncontrast sequences and two postcontrast sequences (which are required only in select clinical scenarios). The working group also provides recommended acquisition parameters, sequence-specific technical suggestions, and general recommendations for optimal imaging technique. We recommend that all sites imaging children with ARP and CP for clinical care, and particularly those engaged in cooperative group trials for pancreatitis, ensure that their local protocol includes these minimum sequences.

Fluid-attenuated inversion-recovery sequence with fat suppression as an alternative to contrast-enhanced MRI in pediatric synovitis.

BACKGROUND: Non-contrast magnetic resonance imaging (MRI) fluid-attenuated inversion-recovery sequence (FLAIR) with fat suppression (FS) has not been validated in children. OBJECTIVE: Compare FLAIR to T1-weighted post contrast (T1CE) in the detection of knee synovitis. METHODS AND MATERIALS: Institutional review board (IRB) waived consent. Children who underwent T1CE and FLAIR sequences of the knee on a 3-T magnet from April 2021 to December 2021 were included. Two pediatric radiologists assessed axial FLAIR and T1CE images for synovitis and synovial thickness. Reliability and agreement were assessed. Sensitivities, specificities, and accuracy were calculated for FLAIR using T1CE as reference standard. RESULTS: In total, 42 knees (39 patients) were assessed (median age 12.9 years (2.3-17.8 years); 62% male, 38% female). Readers judged 20/42 (48%) knees to have synovitis. Sensitivity of FLAIR for reader 1 was 79% (19/24; 95% CI 0.58, 0.93) and 84% (16/19; 95% CI 0.60, 0.97) for reader 2. Specificity of FLAIR for reader 1 was 94% (17/18; 95% CI 0.73, 1) and 83% (19/23; 95% CI 0.61, 0.95) for reader 2. Accuracy for readers 1 and 2 was 86% (36/42; 95% CI 0.71, 0.95) and 83% (35/42; 95% CI 0.69, 0.93), respectively. Inter-reader reliability was good (0.75-0.90) for synovial measurements for FLAIR (ICC = 0.80; 95% CI 0.71, 0.86) and moderate for T1 CE (ICC = 0.62 (95% CI 0.48, 0.73)). CONCLUSION: FLAIR FS depicts synovium in the pediatric knee with similar reliability to T1 CE and may be an acceptable alternative to contrast in the initial diagnosis of synovitis.

Imaging of pediatric adrenal tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper.

Adrenal tumors other than neuroblastoma are uncommon in children. The most frequently encountered are adrenocortical carcinoma and pheochromocytoma. This paper offers consensus recommendations for imaging of pediatric patients with a known or suspected primary adrenal malignancy other than neuroblastoma at diagnosis and during follow-up.

Imaging of pediatric liver tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper.

Primary hepatic malignancies are relatively rare in the pediatric population, accounting for approximately 1%-2% of all pediatric tumors. Hepatoblastoma and hepatocellular carcinoma are the most common primary liver malignancies in children under the age of 5 years and over the age of 10 years, respectively. This paper provides consensus-based imaging recommendations for evaluation of patients with primary hepatic malignancies at diagnosis and follow-up during and after therapy.

Optimizing Imaging of Pediatric Liver Lesions: Guidelines from the Pediatric LI-RADS Working Group.

A differential diagnosis based on a patient's age, clinical presentation, and serum α-fetoprotein level will help guide the initial imaging workup in children with a liver lesion. Children vary significantly in size, the ability to stay still, and the ability to breath hold for imaging examinations. Choosing and tailoring imaging techniques and protocols for each indication and age group is important for optimal care with minimal invasiveness. The need for sedation or anesthesia can be obviated by using techniques like feed and bundle, distraction, contrast-enhanced US, and motion-insensitive sequences for MRI. US is often the first imaging modality used in children with a suspected abdominal mass. Once a hepatic lesion is confirmed, multiphasic contrast-enhanced MRI is recommended for most lesions as the next imaging modality allowing full characterization of the lesion and assessment of the liver parenchyma. Contrast-enhanced CT can also be performed for assessment of pediatric focal liver lesions, especially in patients who have a contraindication to MRI. Contrast-enhanced US has shown promise to decrease the need for MRI or CT in some lesions such as hemangioma and focal nodular hyperplasia. Children with a history of malignancy can develop multiple types of hepatic lesions at various stages, including infections during an immunocompromised state, manifesting as focal liver lesions. Based on available limited data in the literature and the collective experiences of the Liver Imaging and Reporting Data System Pediatric Working Group, the authors provide guidelines for the imaging workup of pediatric focal liver lesions with an indication- and age-based approach and discuss the selection and performance of various imaging techniques and modalities. ©RSNA, 2022 See the invited commentary by Chojniak and Boaventura in this issue.

Cancer Therapy-related Hepatic Injury in Children: Imaging Review from the Pediatric LI-RADS Working Group.

The liver is the primary organ for the metabolism of many chemotherapeutic agents. Treatment-induced liver injury is common in children undergoing cancer therapy. Hepatic injury occurs due to various mechanisms, including biochemical cytotoxicity, hepatic vascular injury, radiation-induced cytotoxicity, and direct hepatic injury through minimally invasive and invasive surgical treatments. Treatment-induced liver injury can be seen contemporaneous with therapy and months to years after therapy is complete. Patients can develop a combination of hepatic injuries manifesting during and after treatment. Acute toxic effects of cancer therapy in children include hepatitis, steatosis, steatohepatitis, cholestasis, hemosiderosis, and vascular injury. Longer-term effects of cancer therapy include hepatic fibrosis, chronic liver failure, and development of focal liver lesions. Quantitative imaging techniques can provide useful metrics for disease diagnosis and monitoring, especially in treatment-related diffuse liver injury such as hepatic steatosis and steatohepatitis, hepatic iron deposition, and hepatic fibrosis. Focal liver lesions, including those developing as a result of treatment-related vascular injury such as focal nodular hyperplasia-like lesions and hepatic perfusion anomalies, as well as hepatic infections occurring as a consequence of immune suppression, can be anxiety provoking and confused with recurrent malignancy or hepatic metastases, although there often are imaging features that help elucidate the correct diagnosis. Radiologic evaluation, in conjunction with clinical and biochemical screening, is integral to diagnosing and monitoring hepatic complications of cancer therapy in pediatric patients during therapy and after therapy completion for long-term surveillance. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material See the invited commentary by Ferraciolli and Gee in this issue.

Imaging Features of Hepatocellular Carcinoma in Children With and Without Underlying Risk Factors.

BACKGROUND. Pediatric hepatocellular carcinoma (HCC) is an aggressive malignancy for which imaging findings remain poorly described. In comparison with adult HCC, pediatric HCC more commonly occurs without underlying risk factors, and standardized surveillance guidelines for those with predispositions are lacking. OBJECTIVE. The purpose of this article was to evaluate imaging findings of nonfibrolamellar pediatric HCC and to identify associations between these imaging findings and the presence of predisposing factors. METHODS. This retrospective study included children (≤ 18 years) with histologically confirmed nonfibrolamellar HCC who underwent multiphase CT or MRI at one of four academic children's hospitals between July 2009 and April 2019. Surveillance regimens in children with predispositions were at the discretion of treating physicians. Clinical characteristics were recorded. Scan indications were classified as surveillance versus clinical signs and symptoms. Images from all sites were submitted to a cloud-based server. Two radiologists independently assessed imaging features of HCC, including tumor size, tumor in vein, Pre-Treatment Extent of Tumor (PRETEXT) stage, and LI-RADS major features of adult HCC. Imaging findings were compared between patients with and without predispositions. RESULTS. The study included 39 patients: 17 with predispositions (mean age, 10.5 ± 4.5 years; nine boys, eight girls) and 22 without predispositions (mean age, 11.3 ± 5.1 years; 12 boys, 10 girls). Scan indication was surveillance in 14/17 patients with predispositions versus 0/22 patients without predispositions (p < .001). Patients with versus those without predispositions had smaller tumor size (reader 1: 6.0 vs 11.9 cm [p = .003]; reader 2: 6.0 vs 12.9 cm [p < .001]) and less frequent tumor in vein (reader 1: 0% vs 41% [p = .002]; reader 2: 0% vs 36% [p = .006]). PRETEXT stage IV disease was observed in 18% (both readers) of patients with predispositions versus 50-55% of patients without predispositions. No LI-RADS major feature of adult HCC showed a significant difference in frequency between patients with and without predispositions for either reader (all p > .05). CONCLUSION. Among children with HCC, those with predispositions exhibited smaller and lower-stage tumors and less frequent tumor in vein, likely because of surveillance imaging. CLINICAL IMPACT. The study supports the role of routine surveillance imaging in children with HCC predispositions to facilitate earlier detection. Standardization of surveillance guidelines remains needed.

Interobserver Agreement for CT and MRI Findings of Chronic Pancreatitis in Children: A Multicenter Ancillary Study Under the INSPPIRE Consortium.

BACKGROUND. Imaging findings represent key criteria for diagnosing chronic pancreatitis in children. Understanding radiologists' agreement for imaging findings is critical to standardizing and optimizing diagnostic criteria. OBJECTIVE. The purpose of this study is to evaluate the interobserver agreement among experienced pediatric radiologists for subjective, quantitative, and semiquantitative imaging findings of chronic pancreatitis in children. METHODS. In this retrospective study, CT or MRI examinations performed in children with chronic pancreatitis were submitted by six sites participating in the INSPPIRE (International Study Group of Pediatric Pancreatitis: In Search for a Cure) Consortium. One pediatric radiologist from each of the six sites reviewed examinations; three of the radiologists independently reviewed all CT examinations, and the other three radiologists independently reviewed all MRI examinations. Reviewers recorded 13 categoric imaging findings of chronic pancreatitis and measured pancreas thickness and pancreatic duct diameter. Agreement was assessed using kappa coefficients for the categoric variables and intraclass correlation coefficients (ICCs) for the continuous variables. RESULTS. A total of 76 CT and 80 MRI examinations performed in 110 children (65 girls and 45 boys; mean age, 11.3 ± 4.6 [SD] years) were reviewed. For CT, kappa coefficients for categoric findings ranged from -0.01 to 0.81, with relatively high kappa coefficients noted for parenchymal calcifications (κ = 0.81), main pancreatic duct dilatation (κ = 0.63), and atrophy (κ = 0.52). ICCs for parenchymal thickness measurements ranged from 0.57 in the pancreas head to 0.80 in the body and tail. The ICC for duct diameter was 0.85. For MRI, kappa coefficients for categoric findings ranged from -0.01 to 0.74, with relatively high kappa coefficients noted for main duct irregularity (κ = 0.74), side branch dilatation (κ = 0.70), number of dilated side branches (κ = 0.65), and main duct dilatation (κ = 0.64); kappa coefficient for atrophy was 0.52. ICCs for parenchymal thickness measurements ranged from 0.53 for the neck and body individually to 0.68 in the tail. ICC for duct diameter was 0.77. CONCLUSION. Interobserver agreement was fair to moderate for most CT and MRI findings of chronic pancreatitis in children. CLINICAL IMPACT. This study highlights challenges for the imaging diagnosis of pediatric chronic pancreatitis. Standardized and/or objective criteria are needed given the importance of imaging in diagnosis.

Ultrasound of congenital spine anomalies.

Ultrasonography (US) is the first-line imaging modality for screening neonates and young infants with suspected spinal abnormalities. Whether performed for a suspicious congenital skin lesion, such as a lumbosacral tract or lipomatous mass, or abnormal neurological findings, US can help define spinal anatomy, characterize congenital spine malformations, and direct further work-up and management. The purpose of this article is to review the diagnostic imaging approach to infant spine US, including technique and indications, normal anatomy and variants with a focus on embryological origins, and classification and diagnosis of congenital spine malformations.

Imaging of Intestinal and Multivisceral Transplantation.

Intestinal transplantation has evolved from its experimental origins in the mid-20th century to its status today as an established treatment option for patients with end-stage intestinal failure who cannot be sustained with total parenteral nutrition. The most common source of intestinal failure in both adults and children is short-bowel syndrome, but a host of other disease processes can lead to this common end-point. The development of intestinal transplantation has presented multiple hurdles for the transplant community, including technical challenges, immunologic pitfalls, and infectious complications. Despite these hurdles, the success rate has climbed over the past decades owing to achievements that include improved surgical techniques, new immunosuppressive regimens, and more effective strategies for posttransplant surveillance and management. Nearly 2800 intestinal transplants have been performed worldwide, and current patient and graft survival rates are now comparable to those of other types of solid organ transplantations. As their population continues to increase, it will be increasingly likely that intestinal-transplant patients will seek imaging at sites other than transplant centers. Therefore, it is important that diagnostic and interventional radiologists be familiar with the procedure, its common variations, and the spectrum of postoperative complications. In this article, the authors provide an overview of intestinal transplantation, including the indications, variations, expected postoperative anatomy, and range of potential complications. ©RSNA, 2018.

Delayed splenic vascular injury after nonoperative management of blunt splenic trauma.

BACKGROUND: Delayed splenic vascular injury (DSVI) is traditionally considered a rare, often clinically occult, harbinger of splenic rupture in patients with splenic trauma that are managed conservatively. The purpose of our study was to assess the incidence of DSVI and associated features in patients admitted with blunt splenic trauma and managed nonoperatively. MATERIALS AND METHODS: A retrospective analysis was conducted over a 4-y time. Patients admitted with blunt splenic trauma, managed no-operatively and with a follow-up contrast-enhanced computed tomography (CT) scan study during admission were included. The CT scans were reviewed for American Association for the Surgery of Trauma splenic injury score, amount of hemoperitoneum, and presence of DSVI. Logistic regression models were used to investigate the risk factors associated with DSVI. RESULTS: A total of 100 patients (60 men and 40 women) constituted the study group. Follow-up CT scan demonstrated a 23% incidence of DSVI. Splenic artery angiography validated DSVI in 15% of the total patient population. Most DSVIs were detected only on arterial phase CT scan imaging. The American Association for the Surgery of Trauma splenic injury score (odds ratio = 1.73; P = 0.045) and the amount of hemoperitoneum (odds ratio = 1.90; P = 0.023) on admission CT scan were associated with the development of DSVI on follow-up CT scan. CONCLUSIONS: DSVI on follow-up CT scan imaging of patients managed nonoperatively after splenic injury is common and associated with splenic injury score assessed on admission CT scan.

Canal of Nuck hernia: a multimodality imaging review.

Canal of Nuck abnormalities are a rare but important cause of morbidity in girls, most often those younger than 5 years of age. The canal of Nuck, which is the female equivalent of the male processus vaginalis, is a protrusion of parietal peritoneum that extends through the inguinal canal and terminates in the labia majora. The canal typically obliterates early in life, but in some cases the canal can partially or completely fail to close, potentially resulting in a hydrocele or hernia of pelvic contents. Recognition of this entity is especially important in cases of ovarian hernia due to the risk of incarceration and torsion. We aim to increase awareness of this condition by reviewing the embryology, anatomy and diagnosis of canal of Nuck disorders with imaging findings on US, CT and MRI using several cases from a single institution.

Hepatic sarcoidosis in patients presenting with liver dysfunction: imaging appearance, pathological correlation and disease evolution.

OBJECTIVES: We hypothesize that hepatic sarcoidosis is a dynamic process that can lead to cirrhosis and portal hypertension, independent of the course of thoracic disease. Therefore, we assess the imaging appearance and progression of hepatic sarcoidosis in subjects presenting with hepatic dysfunction. METHODS: An IRB-approved, HIPAA-compliant, single-institution retrospective review identified 39 subjects with sarcoidosis-related liver dysfunction. Clinical information was collected. Two abdominal radiologists analyzed baseline and follow-up imaging studies, scoring features of cirrhosis. Chest CT was also analyzed. RESULTS: At presentation, 23 subjects (59.0 %) exhibited >3 cirrhotic features and 15 (38.5 %) >2 findings of portal hypertension. Of subjects with available follow-up, 57.9 % (19 subjects; mean interval 4.7 years) showed worsening of >3 cirrhotic features (Pearson rho = 0.58; p = 0.009). Parenchymal nodules were uncommon (25.6 %), and most regressed. Although 87.2 % of subjects were diagnosed with thoracic sarcoidosis, there was poor correlation between severity of hepatic and chest disease (Pearson rho = 0.30; p = 0.119). A mean of 7.2 years elapsed between diagnosis of pulmonary and liver involvement. CONCLUSION: Sarcoidosis may present as liver dysfunction, cirrhosis or portal hypertension. Sarcoid-related liver disease may progress and can manifest without, alongside or significantly after a diagnosis of pulmonary disease. KEY POINTS: • Patients often present with elevated liver function tests indicating cholestasis. • Patients may present with portal hypertension, and some progress to cirrhosis. • Though biopsy can be considered for focal liver lesions, most will regress. • Extent of intra-abdominal involvement may not correlate with severity of thoracic disease. • Liver disease may manifest alongside, prior to or significantly after initial diagnosis.

Inter-radiologist agreement using Society of Abdominal Radiology-American Gastroenterological Association (SAR-AGA) consensus nomenclature for reporting CT and MR enterography in children and young adults with small bowel Crohn disease.

PURPOSE: To assess inter-radiologist agreement using the Society of Abdominal Radiology-American Gastroenterological Association (SAR-AGA) consensus recommendations for reporting CT/MR enterography exams in pediatric and young adult small bowel Crohn disease (CD). METHODS: Institutional review board approval was obtained for this HIPAA-compliant retrospective investigation; the requirement for informed consent was waived. 25 CT and 25 MR enterography exams performed in children and young adults (age range: 6-23 years) between January 2015 and April 2017 with a distribution of ileal CD severity (phenotype) were identified: normal or chronic CD without active inflammation (40%), active inflammatory CD (20%), stricturing CD (20%), and penetrating CD (20%). Five fellowship-trained pediatric radiologists, blinded to one another, documented key imaging findings and standardized impressions based on SAR-AGA consensus recommendations. Inter-radiologist agreement was evaluated using Fleiss' multi-rater kappa statistic (κ) with 95% confidence intervals (CI). RESULTS: Inter-radiologist agreement was moderate for all key imaging findings except presence of ulcerations (κ 0.37 [95% CI 0.28-0.46]) and sacculations (κ 0.31 [95% CI 0.23-0.40]). Agreement for standardized impressions was substantial for stricturing disease (κ 0.79 [95% CI 0.70-0.87]) and moderate for presence of inflammation (κ 0.49 [95% CI 0.44-0.56]) and penetrating disease (κ 0.58 [95% CI 0.49-0.67]). No significant difference in agreement was found between CT and MRI. CONCLUSIONS: Agreement among five pediatric radiologists was moderate to substantial for SAR-AGA standardized impressions and fair to moderate for key imaging findings of pediatric and young adult CD.