European Society of Pediatric Radiology survey of perioperative imaging in pediatric liver transplantation: (1) pre-transplant evaluation.

BACKGROUND: Liver transplantation is the state-of-the-art curative treatment in end-stage liver disease. Imaging is a key element for successful organ-transplantation to assist surgical planning. So far, only limited data regarding the best radiological approach to prepare children for liver transplantation is available. OBJECTIVES: In an attempt to harmonize imaging surrounding pediatric liver transplantation, the European Society of Pediatric Radiology (ESPR) Abdominal Taskforce initiated a survey addressing the current status of imaging including the pre-, intra-, and postoperative phase. This paper reports the responses on preoperative imaging. MATERIAL AND METHODS: An online survey, initiated in 2021, asked European centers performing pediatric liver transplantation 48 questions about their imaging approach. In total, 26 centers were contacted and 22 institutions from 11 countries returned the survey. From 2018 to 2020, the participating centers collectively conducted 1,524 transplantations, with a median of 20 transplantations per center per annum (range, 8-60). RESULTS: Most sites (64%) consider ultrasound their preferred modality to define anatomy and to plan surgery in children before liver transplantation, and additional cross-sectional imaging is only used to answer specific questions (computed tomography [CT], 90.9%; magnetic resonance imaging [MRI], 54.5%). One-third of centers (31.8%) rely primarily on CT for pre-transplant evaluation. Imaging protocols differed substantially regarding applied CT scan ranges, number of contrast phases (range 1-4 phases), and applied MRI techniques. CONCLUSION: Diagnostic imaging is generally used in the work-up of children before liver transplantation. Substantial differences were noted regarding choice of modalities and protocols. We have identified starting points for future optimization and harmonization of the imaging approach to multicenter studies.

European Society of Pediatric Radiology survey of perioperative imaging in pediatric liver transplantation: (2) intraoperative imaging.

BACKGROUND: Liver transplantation is the state-of-the-art curative treatment for end-stage liver disease. Imaging is a key element in the detection of intraoperative and postoperative complications. So far, only limited data regarding the best radiological approach to monitor children during liver transplantation is available. OBJECTIVE: To harmonize the imaging of pediatric liver transplantation, the European Society of Pediatric Radiology Abdominal Taskforce initiated a survey addressing the current status of imaging including the pre-, intra- and postoperative phase. This paper reports the responses related to intraoperative imaging. MATERIALS AND METHODS: An online survey, initiated in 2021, asked European centers performing pediatric liver transplantation 48 questions about their imaging approach. In total, 26 centers were contacted, and 22 institutions from 11 countries returned the survey. RESULTS: Intraoperative ultrasound (US) is used by all sites to assess the quality of the vascular anastomosis in order to ensure optimal perfusion of the liver transplant. Vessel depiction is commonly achieved using color Doppler (95.3%). Additional US-based techniques are employed by fewer centers (power angio mode, 28.6%; B-flow, 19%; contrast-enhanced US, 14.3%). Most centers prefer a collaborative approach, with surgeons responsible for probe handling, while radiologists operate the US machine (47.6%). Less commonly, the intraoperative US is performed by the surgeon alone (28.6%) or by the radiologist alone (23.8%). Timing of US, imaging frequency, and documentation practices vary among centers. CONCLUSION: Intraoperative US is consistently utilized across all sites during pediatric liver transplantation. However, considerable variations were observed in terms of the US setup, technique preferences, timing of controls, and documentation practices. These differences provide valuable insights for future optimization and harmonization studies.

European Society of Pediatric Radiology survey of perioperative imaging in pediatric liver transplantation: (3) postoperative imaging.

BACKGROUND: Liver transplantation is the state-of-the-art curative treatment for end-stage liver disease. Imaging is a key element in the detection of postoperative complications. So far, limited data is available regarding the best radiologic approach to monitor children after liver transplantation. OBJECTIVE: To harmonize the imaging of pediatric liver transplantation, the European Society of Pediatric Radiology Abdominal Taskforce initiated a survey addressing the current status of imaging including the pre-, intra-, and postoperative phases. This paper reports the responses related to postoperative imaging. MATERIALS AND METHODS: An online survey, initiated in 2021, asked European centers performing pediatric liver transplantation 48 questions about their imaging approach. In total, 26 centers were contacted, and 22 institutions from 11 countries returned the survey. RESULTS: All sites commence ultrasound (US) monitoring within 24 h after liver transplantation. Monitoring frequency varies across sites, ranging from every 8 h to 72 h in early, and from daily to sporadic use in late postoperative phases. Predefined US protocols are used by 73% of sites. This commonly includes gray scale, color Doppler, and quantitative flow assessment. Alternative flow imaging techniques, contrast-enhanced US, and elastography are applied at 31.8%, 18.2%, and 63.6% of sites, respectively. Computed tomography is performed at 86.4% of sites when clarification is needed. Magnetic resonance imaging is used for selected cases at 36.4% of sites, mainly for assessment of biliary abnormalities or when blood tests are abnormal. CONCLUSION: Diagnostic imaging is extensively used for postoperative surveillance of children after liver transplantation. While US is generally prioritized, substantial differences were noted in US protocol, timing, and monitoring frequency. The study highlights potential areas for future optimization and standardization of imaging, essential for conducting multicenter studies.

Historical and Contemporary Management of Infantile Hepatic Hemangioma: A 30-year Single-center Experience.

OBJECTIVE: To describe outcome of infants with hemangioma(s) of the liver. SUMMARY OF BACKGROUND DATA: Infantile hepatic hemangiomas exhibit a diverse phenotype. We report our 30-year experience and describe optimal management based on precise radiological classification. METHODS: Retrospective review of 124 infants (66 female) 1986-2016. Categorical analysis with Chi2 and nonparametric comparison. Data expressed as median (range) and P < 0.05 considered significant. RESULTS: Lesions classified as focal (n = 70, 56%); multifocal (n = 47, 38%) or diffuse (n = 7, 6%) and of these 80(65%) were symptomatic (eg, cardiac failure n = 39, 31%; thrombocytopenia n = 12, 10%).Increased hepatic artery velocity was seen in 63 (56%). Median hepatic artery velocity was greatest in diffuse lesions [245 (175-376) cm/s vs focal 120 (34-242) cm/s vs multifocal 93 (36-313) cm/s; P = 0.0001]. Expectant management alone was followed in 55 (44%). Medical therapy was utilised in 57(46%) and sufficient for symptom control in 29/57 (51%). Propranolol therapy (from 2008) was sufficient for symptom control in 22/28 (79%). Surgery (hepatic artery ligation n = 26; resection n = 13; embolization n = 1) was required in 40 (32%). Median maximal lesion diameter was 3 (0.5-17.1) cm and greater in those requiring surgery (7 cm vs 4.9 cm; P = 0.04). The proportion requiring surgery decreased markedly in the propranolol era [pre-propranolol 25/48 (52%) vs post-propranolol 16/76 (21%) (P = 0.0003)]. Systematic follow-up with ultrasound to a median of 2.6 (0.02-16) years. CONCLUSIONS: A proportion of infantile hepatic hemangiomas remain asymptomatic permitting observation until resolution but the majority require complex multi-modal therapy. First-line pharmacotherapy with propranolol has reduced but not abolished the need for surgery.

Microvascular Flow Imaging: A State-of-the-Art Review of Clinical Use and Promise.

Vascular imaging with color and power Doppler is a useful tool in the assessment of various disease processes. Assessment of blood flow, from infarction and ischemia to hyperemia, in organs, neoplasms, and vessels, is used in nearly every US investigation. Recent developments in this area are sensitive to small-vessel low velocity flow without use of intravenous contrast agents, known as microvascular flow imaging (MVFI). MVFI is more sensitive in detection of small vessels than color, power, and spectral Doppler, reducing the need for follow-up contrast-enhanced US (CEUS), CT, and MRI, except when arterial and venous wash-in and washout characteristics would be helpful in diagnosis. Varying clinical applications of MVFI are reviewed in adult and pediatric populations, including its technical underpinnings. MVFI shows promise in assessment of several conditions including benign and malignant lesions in the liver and kidney, acute pathologic abnormalities in the gallbladder and testes, and superficial lymph nodes. Future potential of MVFI in different conditions (eg, endovascular repair) is discussed. Finally, clinical cases in which MVFI correlated and potentially obviated additional CEUS, CT, or MRI are shown.

Contrast-Enhanced Ultrasound Quantification Assessment of Focal Fatty Variations in Liver Parenchyma: Challenging the Traditional Qualitative Paradigm of Uniform Enhancement With Adjacent Parenchyma.

OBJECTIVES: The purpose of this study was to quantify contrast-enhanced ultrasound enhancement of focal fatty sparing (FFS) and focal fatty infiltration (FFI) and compare it with adjacent liver parenchyma. METHODS: This was a retrospective observational study yielding 42 cases in the last 4 years. Inclusion criteria were a focal liver lesion, adequate video availability, and an established diagnosis of FFS or FFI based on clinical or imaging follow-up or a second modality. Contrast-enhanced ultrasound examinations were performed with a standard low-mechanical index technique. Commercially available software calculated quantitative parameters for a focal liver lesion and a reference area of liver parenchyma, producing relative indices. RESULTS: In total, 42 patients were analyzed (19 male) with a median age of 18 (interquartile range, 42) years and a median lesion diameter of 30 (interquartile range, 16) mm. The cohort included 26 with FFS and 16 with FFI. Subjectively assessed, 27% of FFS and 25% of FFI were hypoenhancing in the arterial phase, and 73% of FFS and 75% of FFI were isoenhancing. In the venous and delayed phases, all lesions were isoenhancing. The peak enhancement (P = .001), wash-in area under the curve (P < .01), wash-in rate (P = .023), and wash-in perfusion index (P = .001) were significantly lower in FFS compared with adjacent parenchyma but not the mean transit time. In the FFI subgroup, no significant difference was detected. Comparing relative parameters, only the wash-in rate was significantly (P = .049) lower in FFS than FFI. The mean follow-up was 2.8 years. CONCLUSIONS: Focal fatty sparing shows significantly lower and slower enhancement than the liver parenchyma, whereas FFI enhances identically. Focal fatty sparing had a significantly slower enhancement than FFI.

Contrast-enhanced ultrasound of blunt abdominal trauma in children.

Trauma is the leading cause of morbidity and mortality in children, and rapid identification of organ injury is essential for successful treatment. Contrast-enhanced ultrasound (CEUS) is an appealing alternative to contrast-enhanced CT in the evaluation of children with blunt abdominal trauma, mainly with respect to the potential reduction of population-level exposure to ionizing radiation. This is particularly important in children, who are more vulnerable to the hazards of ionizing radiation than adults. CEUS is useful in hemodynamically stable children with isolated blunt low- to moderate-energy abdominal trauma to rule out solid organ injuries. It can also be used to further evaluate uncertain contrast-enhanced CT findings, as well as in the follow-up of conservatively managed traumatic injuries. CEUS can be used to detect abnormalities that are not apparent by conventional US, including infarcts, pseudoaneurysms and active bleeding. In this article we present the current experience from the use of CEUS for the evaluation of pediatric blunt abdominal trauma, emphasizing the examination technique and interpretation of major abnormalities associated with injuries in the liver, spleen, kidneys, adrenal glands, pancreas and testes. We also discuss the limitations of the technique and offer a review of the major literature on this topic in children, including an extrapolation of experience from adults.

Contrast-enhanced ultrasound of the kidneys and adrenals in children.

Pediatric applications of contrast-enhanced ultrasound (CEUS) are growing. Evaluation of the kidneys and adrenal glands in children using intravenous administration of US contrast agents, however, is still an off-label indication. Pediatric CEUS applications for kidneys are similar to those in adults, including ischemic disorders, pseudo- versus real tumors, indeterminate lesions, complex cystic lesions, complicated pyelonephritis, and abscesses. CEUS applications for evaluation of adrenal glands in children are limited, mainly focusing on the assessment and follow-up of adrenal trauma and the differentiation between an adrenal hemorrhage and a mass. This review addresses the current experience in pediatric CEUS of the kidneys and adrenal glands. By extrapolating the established knowledge for US contrast evaluations in the adult kidney to the pediatric context we can note opportunities for CEUS clinical use in children.

European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB): An Update on the Pediatric CEUS Registry on Behalf of the "EFSUMB Pediatric CEUS Registry Working Group".

The European Federation of Ultrasound in Medicine and Biology (EFSUMB) created the "EFSUMB Pediatric Registry" (EFSUMB EPR) with the purpose of collecting data regarding the intravenous application of pediatric contrast-enhanced ultrasound (CEUS). The primary aim was to document the current clinical practice and usefulness of the technique and secondarily to assess CEUS safety in children. We issue the preliminary results of this database and examine the overall practice of CEUS in children in Europe.

Contrast-enhanced ultrasound in the diagnosis of pediatric focal nodular hyperplasia and hepatic adenoma: interobserver reliability.

BACKGROUND: Focal nodular hyperplasia and hepatic adenoma are rare liver tumors in which specific features on contrast-enhanced ultrasound (US) have been reported but are little known in children. OBJECTIVE: To assess the interobserver agreement in diagnosing and differentiating focal nodular hyperplasia and hepatic adenoma in children using established adult contrast-enhanced US characteristics. MATERIALS AND METHODS: Thirty children with a definite or probable diagnosis of focal nodular hyperplasia or hepatic adenoma on magnetic resonance imaging (MRI)/histology who underwent contrast-enhanced US studies were included. Typical and additional contrast-enhanced US features of focal nodular hyperplasia and hepatic adenoma were included. The lesions were classified as definite/probable focal nodular hyperplasia, definite/probably hepatic adenoma or unclassified. The interobserver kappa of contrast-enhanced US characteristics was calculated. RESULTS: Focal nodular hyperplasia and hepatic adenoma in children demonstrate contrast-enhanced US characteristics similar to those in adults. Among the nine lesions with confirmed histological diagnosis, correct diagnosis was made in 7 (77.8%) based on contrast-enhanced US criteria. Two lesions were unclassified by both observers due to a mixed arterial filling pattern. Interobserver kappa for contrast-enhanced US diagnosis was 0.64 (P<0.0001). CONCLUSION: There is a good interobserver kappa for separating focal nodular hyperplasia from hepatic adenoma in children using established adult contrast-enhanced US features.

The EFSUMB Guidelines and Recommendations for the Clinical Practice of Contrast-Enhanced Ultrasound (CEUS) in Non-Hepatic Applications: Update 2017 (Long Version).

The updated version of the EFSUMB guidelines on the application of non-hepatic contrast-enhanced ultrasound (CEUS) deals with the use of microbubble ultrasound contrast outside the liver in the many established and emerging applications.

The EFSUMB Guidelines and Recommendations for the Clinical Practice of Contrast-Enhanced Ultrasound (CEUS) in Non-Hepatic Applications: Update 2017 (Short Version).

The updated version of the EFSUMB guidelines on the application of non-hepatic contrast-enhanced ultrasound (CEUS) deals with the use of microbubble ultrasound contrast outside the liver in the many established and emerging applications.

Autoimmune Liver Disease in Children with Sickle Cell Disease.

OBJECTIVE: To assess the incidence, clinical features, and outcome of autoimmune liver disease (AILD) in patients with sickle cell disease (SCD). STUDY DESIGN: Single center retrospective review of patients with SCD with AILD referred between 1999 and 2015. RESULTS: Thirteen of 77 (17%) patients with SCD with hepatic dysfunction were diagnosed with AILD (median age 11, range, 3.4-16 years) with a female preponderance (77%). Acute hepatitis and insidious onset were the commonest presentations. Two patients (15%) presented with acute liver failure. In 2 patients (15%), parvovirus B19-induced transient red cell aplasia preceded the diagnosis of AILD. All patients were positive for antinuclear and/or smooth muscle autoantibodies. Six of 12 patients (50%) had cholangiopathy on cholangiogram suggesting autoimmune sclerosing cholangitis (ASC). Liver biopsy, performed in 11 patients without complications, showed interface hepatitis in 90%. Patients with AILD were treated with standard immunosuppression. After a median follow-up of 3.8 years (range, 0.2-14.3), 10 patients are alive (1 was transplanted 6.4 years after diagnosis); 2 are lost to follow-up; 1 died of subdural hemorrhage before starting treatment for AILD. Five (42%) achieved full and 4 (33%) partial biochemical remission. Ulcerative colitis, present in 4 patients (2 male patients, 3 with ASC) was diagnosed in 2 patients before and in 2 patients after the diagnosis of AILD. CONCLUSIONS: AILD is not uncommon in patients with SCD, affecting mainly female patients and responding satisfactorily to immunosuppressive treatment. Liver biopsy is helpful in confirming the diagnosis and can be safely performed in the absence of acute vaso-occlusive sickling episodes. Ulcerative colitis is common in the presence of ASC.

Retrospective Analysis of the Safety and Cost Implications of Pediatric Contrast-Enhanced Ultrasound at a Single Center.

OBJECTIVE: Because of concern over medical ionizing radiation exposure of children, contrast-enhanced ultrasound (CEUS) has generated interest as an inexpensive, ionizing radiation-free alternative to CT and MRI. CEUS has received approval for pediatric hepatic use but remains off-label for a range of other applications. The purposes of this study were to retrospectively analyze adverse incidents encountered in pediatric CEUS and to assess the financial benefits of reducing the number of CT and MRI examinations performed. MATERIALS AND METHODS: All pediatric (patients 18 years and younger) CEUS examinations performed between January 2008 and December 2015 were reviewed. All immediate reactions deemed due to contrast examinations were documented in radiology reports. Electronic patient records were examined for adverse reactions within 24 hours not due to an underlying pathologic condition. With tariffs from the U.K. National Institute of Clinical Excellence analysis, CEUS utilization cost ($94) was compared with the CT ($168) and MRI ($274) costs of the conventional imaging pathway. RESULTS: The records of 305 pediatric patients (187 boys, 118 girls; age range, 1 month-18 years) undergoing CEUS were reviewed. Most of the studies were for characterizing liver lesions (147/305 [48.2%]) and trauma (113/305 [37.1%]); the others were for renal, vascular, and intracavitary assessment (45/305 [14.8%]). No immediate adverse reactions occurred. Delayed adverse reactions occurred in two patients (2/305 [0.7%]). These reactions were transient hypertension and transient tachycardia. Neither was symptomatic, and both were deemed not due to the underlying disorder. The potential cost savings of CEUS were $74 per examination over CT and $180 over MRI. CONCLUSION: Pediatric CEUS is a safe and potentially cost-effective imaging modality. Using it allows reduction in the ionizing radiation associated with CT and in the gadolinium contrast administration, sedation, and anesthesia sometimes required for MRI.

Intravenous and Intracavitary Use of Contrast-Enhanced Ultrasound in the Evaluation and Management of Complicated Pediatric Pneumonia.

Pediatric pneumonia can be complicated by necrotizing pneumonia or a parapneumonic effusion either in the form of an empyema or a clear effusion. Ultrasonography (US) and computed tomography represent well-established modalities for evaluation of complicated pediatric pneumonia. Contrast-enhanced ultrasound (CEUS) was recently introduced and is gaining increasing acceptance in pediatric imaging. In this case series, we present our initial experience with both intravenous and intracavitary use of CEUS in children with complicated pneumonia. Intravenous CEUS accurately and confidently showed necrotizing pneumonia and delineated pleural effusions, whereas intracavitary CEUS accurately identified the chest catheter location and patency and showed the presence of loculations, suggesting the use of fibrinolytics.

Multiparametric Sonography of Hematologic Malignancies of the Testis: Grayscale, Color Doppler, and Contrast-Enhanced Ultrasound and Strain Elastographic Appearances With Histologic Correlation.

Primary testicular lymphoma is rare and appears with nonspecific findings on grayscale and color Doppler sonography. We present 8 patients further examined with contrast-enhanced sonography, strain elastography, and histologic analysis after orchiectomy. Seven of 8 patients had a diagnosis of large B-cell lymphoma, and 1 of 8 had a diagnosis of granulocytic sarcoma, with solitary lesions (2 of 8), multiple lesions (3 of 8), or entire testicular involvement (3 of 8). Lesions appeared hypoechoic (7 of 8) or isoechoic (1 of 8), all with increased vascularity on color Doppler sonography and a nonbranching linear pattern of intratumoral vessels (7 of 8). Contrast-enhanced ultrasound (CEUS) confirmed this pattern and showed increased enhancement in all lesions. On strain elastography, all lesions were hard, with an elasticity score of greater than 4. Multiparametric sonography of testicular lymphoma identifies increased vascularity on color Doppler and contrast-enhanced ultrasound and increased lesion stiffness on strain elastography.

Role of Contrast-Enhanced Ultrasound (CEUS) in Paediatric Practice: An EFSUMB Position Statement.

The use of contrast-enhanced ultrasound (CEUS) in adults is well established in many different areas, with a number of current applications deemed "off-label", but the use supported by clinical experience and evidence. Paediatric CEUS is also an "off-label" application until recently with approval specifically for assessment of focal liver lesions. Nevertheless there is mounting evidence of the usefulness of CEUS in children in many areas, primarily as an imaging technique that reduces exposure to radiation, iodinated contrast medium and the "patient-friendly" circumstances of ultrasonography. This position statement of the European Federation of Societies in Ultrasound and Medicine (EFSUMB) assesses the current status of CEUS applications in children and makes suggestions for further development of this technique.

Cortical necrosis secondary to trauma in a child: contrast-enhanced ultrasound comparable to magnetic resonance imaging.

Cortical necrosis is an uncommon cause of renal impairment and is rarely a consequence of blunt abdominal trauma. We present a case of unilateral traumatic acute cortical necrosis in a child demonstrated on contrast-enhanced US with confirmation on MRI. Contrast-enhanced US provides a rapid, accurate evaluation of renal parenchyma abnormalities in blunt abdominal trauma in children without exposure to ionising radiation or the risk of sedation.