Percutaneous recanalization of non-cirrhotic extrahepatic portal vein obstruction in children: technical considerations in a preliminary cohort.

OBJECTIVES: Portal hypertension resulting from non-cirrhotic extrahepatic portal vein obstruction (EHPVO) in children has been primarily managed with the Meso-Rex bypass, but only a few patients have a viable Rex recessus, required by surgery. This study reports a preliminary series of patients who underwent interventional radiology attempts at portal vein recanalization (PVR), with a focus on technical aspects and safety. METHODS: A retrospective review of consecutive patients with severe portal hypertension due to non-cirrhotic EHPVO at a single institution from 2022, who underwent percutaneous attempts at PVR, was performed. Technical and clinical data including fluoroscopy time, radiation exposure, technical and clinical success, complications and follow-up were recorded. RESULTS: Eleven patients (6 males and 5 females; median age 7 years, range 1-14) underwent 15 percutaneous transhepatic (n = 1), transplenic (n = 11), or simultaneous transhepatic/transplenic (n = 3) procedures. Rex recessus was patent in 4/11 (36%). Fluoroscopy resulted in a high median total dose area product (DAP) of 123 Gycm2 (range 17-788 Gycm2) per procedure. PVR was achieved in 5/11 patients (45%), 3/5 with obliterated Rex recessus. Two adverse events of grade 2 and grade 3 occurred without sequelae. After angioplasty, 4/5 patients required stenting to obtain sustained patency, as demonstrated by colour-Doppler ultrasound in all PVR after a median follow-up of 6 months (range 6-14). CONCLUSION: Our preliminary experience suggests that 45% of children with non-cirrhotic EHPVO can restore portal flow even with obliterated Rex recessus. In non-cirrhotic EHPVO, PVR may be an option, if a Meso-Rex bypass is not feasible, although the radiation exposure deserves attention. CLINICAL RELEVANCE STATEMENT: Innovative percutaneous procedures may have the potential to be an alternative option to the traditional surgical approach in the management of non-cirrhotic EHPVO and its complications in children not eligible for Meso-Rex bypass surgery. KEY POINTS: Non-cirrhotic portal hypertension in children has been traditionally managed by surgery with Meso-Rex bypass creation. Percutaneous PVR may restore the patency of the native portal system even when the Rex recessus is obliterated and surgery has been excluded. Interventional radiological techniques may offer a minimally invasive solution in complex cases of EHPVO in children when Meso-Rex bypass is not feasible.

Image-guided core-needle or surgical biopsy for neuroblastoma diagnosis in children: A systematic review and meta-analysis from the International Society of Pediatric Surgical Oncology (IPSO).

BACKGROUND: Image-guided core-needle biopsy (IGCNB) is a widely used and valuable clinical tool for tissue diagnosis of pediatric neuroblastoma. However, open surgical biopsy remains common practice even if children undergo more invasive and painful procedures. This review aims to determine the diagnostic accuracy and safety of IGCNBs in pediatric patients with neuroblastoma. METHODS: We conducted a systematic review of peer-reviewed original articles published between 1980 and 2023, by searching "pediatric oncology," "biopsy," "interventional radiology," and "neuroblastoma." Exclusion criteria were patients older than 18 years, studies concerning non-neurogenic tumors, case reports, and language other than English. Both the systematic review and meta-analysis were conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. RESULTS: A total of 533 abstracts articles were analyzed. Of these, eight retrospective studies met inclusion criteria (490 infants, 270 surgical biopsies [SB], 220 image-guided biopsies). Tissue adequacy for primary diagnosis (SB: n = 265, 98%; IGCNB: n = 199, 90%; p = .1) and biological characterization (SB: n = 186, 95%; IGCNB: n = 109, 89%; p = .15) was similar with both biopsy techniques, while intraoperative transfusion rate (SB: n = 51, 22%; IGCNB: n = 12, 6%; p = .0002) and complications (%) (SB: n = 58, 21%; IGCNB: n = 14, 6%; p = .005) were higher with surgical biopsy. Length of stay was similar in both groups; however, no additional data about concurrent diagnostic or treatment procedures were available in the analyzed studies. CONCLUSIONS: IGCNB is a safe and effective strategic approach for diagnostic workup of NB and should be considered in preferance to SB wherever possible.

MR and Ultrasound Elastography for Fibrosis Assessment in Children: Practical Implementation and Supporting Evidence-AJR Expert Panel Narrative Review.

Quantitative MRI and ultrasound biomarkers of liver fibrosis have become important tools in the diagnosis and clinical management of children with chronic liver disease (CLD). In particular, MR elastography (MRE) is now routinely performed in clinical practice to evaluate the liver for fibrosis. Ultrasound shear-wave elastography has also become widely performed for this purpose, especially in young children. These noninvasive methods are increasingly used to replace liver biopsy for the diagnosis, quantitative staging, and treatment monitoring of patients with CLD. Although ultrasound has advantages of portability and lower equipment cost, available evidence indicates that MRI may have greater reliability and accuracy in liver fibrosis evaluation. In this AJR Expert Panel Narrative Review, we describe how, why, and when to use MRI- and ultrasound-based elastography methods for liver fibrosis assessment in children. Practical approaches are discussed for adapting and optimizing these methods in children, with consideration of clinical indications, patient preparation, equipment requirements, acquisition technique, as well as pitfalls and confounding factors. Guidance is provided for interpretation and reporting, and representative case examples are presented.

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: (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.

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.

Anomalies of the fetal gallbladder: pre-and postnatal correlations.

The gallbladder is not part of the standard survey of a fetus during obstetrical ultrasound. Yet, some anomalies can be detected. Most are clinically benign, but some are features of or associated with more serious complications. Biliary atresia constitutes the diagnosis with the worst prognosis. Its in utero diagnosis is difficult. Still, markers do exist and should be searched for. Knowledge of the normal appearances, variants and abnormalities of the gallbladder contributes to proper management. Any suspicion should lead to meticulous postnatal workup. Pre- or postnatal magnetic resonance imaging can provide additional information in select cases.

Imaging strategy for focal nodular hyperplasia in children: long-term experience from two specialist European centres.

BACKGROUND: Focal nodular hyperplasia (FNH) in children is a rare but benign tumour, which must be differentiated from malignant entities to avoid unnecessary treatment, leading to potential morbidity. OBJECTIVES: To provide data on imaging findings of these lesions with a suggested algorithm for diagnosis, sampling and follow-up. MATERIALS AND METHODS: This retrospective review evaluated imaging of all patients diagnosed with FNH in two tertiary referral centres in Europe between 1975 and 2018. RESULTS: One hundred and four patients with 137 tumours were reviewed. The mean age at presentation was 8.2 years. The median tumour size was 5 cm (range: 0.3-29 cm). Multiple lesions were seen in 16.3% of patients. The male-to-female ratio was 1:2. CONCLUSION: FNH with typical features on imaging can be safely followed up once the diagnosis has been established. The use of contrast-enhanced ultrasound and magnetic resonance imaging allows accurate characterisation in most cases. Histological sampling is only advised when there is diagnostic doubt. Atypical arterial enhancement of FNH should prompt the search for a congenital portosystemic shunt.

Pediatric hepatic hemangiomas: spectrum and prognostic significance of initial ultrasound findings.

BACKGROUND: Hepatic hemangiomas may be associated with serious complications; however, it is unknown whether ultrasound (US) features can predict complications. OBJECTIVE: To analyze initial US features of hepatic hemangiomas predictive of complications. MATERIALS AND METHODS: This is a single-center retrospective cohort study of clinical, biological, and imaging data of infants with hepatic hemangioma between 2000 and 2018. Patients were categorized as having or not having any complication(s). Associations between initial US features and complications were analyzed through logistic regression. Receiver operating characteristic (ROC) curve analyses were performed to determine optimal cutoff values for continuous variables. Stepwise forward logistic regression was used to construct risk prediction models with training and validation sets. Model calibration and discrimination were evaluated using Hosmer-Lemeshow tests, area under the ROC curve, and overall accuracy. RESULTS: Of 112 infants with hepatic hemangioma, 67 (60%) had focal, 32 (28%) had multifocal, and 13 (12%) had diffuse lesions, with complication rates of 51%, 34%, and 92%, respectively, mostly cardiac (54/57, 95%). The US characteristics of the hemangiomas were diverse. Risk factors for complications included diffuse subtype; large tumor volume (focal forms); elevated peak systolic hepatic arterial velocity (PSV); and hepatic vein dilation. For focal forms, initial tumor volume >40 ml and PSV >100 cm/s had >70% sensitivity and specificity, respectively, to predict complications; a model including these variables had 75% overall accuracy in the validation set. For multifocal/diffuse forms, a PSV >115 cm/s had sensitivity and specificity to predict complications of >70%; a model including this variable had 78% overall accuracy in the validation set. CONCLUSION: Diffuse subtype, large tumor volume, elevated hepatic arterial PSV, and hepatic vein dilation are risk factors for complications of hepatic hemangiomas.

Spontaneous evolution patterns of focal congenital hepatic hemangiomas: a case series of 25 patients.

BACKGROUND: Hepatic hemangiomas are the most common benign liver tumors of infancy. They are termed congenital if fully developed at birth or infantile if they appear in the first weeks of life. Previous studies suggested that most focal hepatic hemangiomas are congenital in nature, exhibit no postnatal growth and have an evolution that parallels their cutaneous counterparts. They are subdivided by pattern of involution, whether rapidly involuting (RICH), partially involuting (PICH) or non-involuting (NICH) congenital hemangiomas. In our experience, some focal hepatic hemangiomas show postnatal growth, behaving like infantile forms. OBJECTIVES: To analyze the spontaneous evolution of focal congenital hepatic hemangiomas with quantification of tumor volume changes over time and to identify initial postnatal ultrasound (US) imaging biomarkers predictive of their evolution pattern. MATERIALS AND METHODS: A retrospective review of clinical, imaging and pathology data of children diagnosed with focal congenital hepatic hemangioma (prenatal diagnosis or age at diagnosis <7 days and/or glucose transporter protein 1 [GLUT1]-negative tumor) diagnosed between 2000 and 2018 was performed with analysis of tumor volume changes over time. Exclusion criteria were treatment inducing a tumor volume change (hepatic artery embolization, propranolol, or corticosteroids), imaging follow-up less than 1 month or fewer than two US examinations. Volumetric analysis was based on US and cross-sectional imaging. Lesion volumes were estimated using the standard ellipsoid formula. A 35% margin of error was assumed for tumor volume variation to account for variability in measurements. Imaging studies, including US, computed tomography, and magnetic resonance imaging, were reviewed and initial postnatal US features were correlated with evolution pattern. RESULTS: Twenty-five patients with focal congenital hepatic hemangiomas were included. The median follow-up time was 46.5 months (range: 4-144 months). Eight (32%) lesions showed postnatal growth before involuting, without signs of intralesional hemorrhage, as do cutaneous infantile hemangiomas. The other 17 (68%) lesions exhibited a strict decrease in volume with age, of which 15 underwent complete involution (8 before age 18 months and 7 after age 18 months) and 2 underwent partial involution. The different evolution patterns of focal congenital hepatic hemangiomas showed overlapping imaging features and we found no initial US feature to be significantly associated with postnatal growth. However, large vascular spaces with marked vascularity at US were noted in three of the eight rapidly involuting lesions. CONCLUSION: Focal congenital hepatic hemangiomas are not the equivalent of cutaneous RICH, as some may increase in size and tumor regression may be rapid or slow. The different evolution patterns of focal congenital hepatic hemangiomas show overlapping US features.

Imaging of anorectal malformations: where are we now? Abdominal imaging task force of the European Society of Paediatric Radiology.

Anorectal and cloacal malformations are a broad mix of congenital abnormalities related to the distal rectum and anus. Confusion exists between all the forms in this large and heterogeneous group. The spectrum includes everything from anal stenosis, ventral anus, anal atresia (with and without fistula) and the full spectrum of cloacal malformations. Imaging in these conditions is done through the whole armamentarium of radiologic modalities, with very different imaging strategies seen across the centres where these conditions are managed. In 2017, the European Society of Paediatric Radiology (ESPR) abdominal imaging task force issued recommendations on the imaging algorithm and standards for imaging anorectal malformations. This was followed by further letters and clarifications together with an active multispecialty session on the different imaging modalities for anorectal malformations at the 2018 ESPR meeting in Berlin. Through this paper, the abdominal task force updates its guidelines and recommended imaging algorithm for anorectal malformations.

Congenital Extrahepatic Portosystemic Shunts (Abernethy Malformation): An International Observational Study.

Congenital extrahepatic portosystemic shunt (CEPS) or Abernethy malformation is a rare condition in which splanchnic venous blood bypasses the liver draining directly into systemic circulation through a congenital shunt. Patients may develop hepatic encephalopathy (HE), pulmonary hypertension (PaHT), or liver tumors, among other complications. However, the actual incidence of such complications is unknown, mainly because of the lack of a protocolized approach to these patients. This study characterizes the clinical manifestations and outcome of a large cohort of CEPS patients with the aim of proposing a guide for their management. This is an observational, multicenter, international study. Sixty-six patients were included; median age at the end of follow-up was 30 years. Nineteen patients (28%) presented HE. Ten-, 20-, and 30-year HE incidence rates were 13%, 24%, and 28%, respectively. No clinical factors predicted HE. Twenty-five patients had benign nodular lesions. Ten patients developed adenomas (median age, 18 years), and another 8 developed HCC (median age, 39 years). Of 10 patients with dyspnea, PaHT was diagnosed in 8 and hepatopulmonary syndrome in 2. Pulmonary complications were only screened for in 19 asymptomatic patients, and PaHT was identified in 2. Six patients underwent liver transplantation for hepatocellular carcinoma or adenoma. Shunt closure was performed in 15 patients with improvement/stability/cure of CEPS manifestations. Conclusion: CEPS patients may develop severe complications. Screening for asymptomatic complications and close surveillance is needed. Shunt closure should be considered both as a therapeutic and prophylactic approach.

Diffuse Versus Localized Caroli Disease: A Comparative MRCP Study.

OBJECTIVE. The purpose of this multicenter retrospective study was to assess the MRCP features of Caroli disease (CD). MATERIALS AND METHODS. Sixty-six patients were identified from 2000 to 2019. The inclusion criteria were diagnosis of diffuse or localized CD mentioned in an imaging report, presence of intrahepatic bile duct (IHBD) dilatation, and having undergone an MRCP examination. The exclusion criteria included presence of obstructive proximal biliary stricture and having undergone hepatobiliary surgery other than cholecystectomy. Histopathology records were available for 53 of the 66 (80%) patients. Diffuse and localized diseases were compared by chi-square and t tests and Kaplan-Meier model. RESULTS. Forty-five patients had diffuse bilobar CD ((five pediatric patients [three girls and two boys] with a mean [± SD] age of 8 ± 5 years [range, 1-15 years] and 40 adult patients [26 men and 14 women] with a mean age of 35 ± 11 years [range, 20-62 years]) and 21 patients had localized disease (12 men and 9 women; mean age, 54 ± 14 years). Congenital hepatic fibrosis was found only in patients with diffuse CD (35/45 [78%]), as was a "central dot" sign (15/35 [43%]). IHBD dilatation with both saccular and fusiform features was found in 43 (96%) and the peripheral "funnel-shaped" sign in 41 (91%) of the 45 patients with diffuse CD but in none of the patients with localized disease (p < .001). Intrahepatic biliary calculi were found in all patients with localized disease but in only 16 of the 45 (36%) patients with diffuse CD (p < .001). Left liver atrophy was found in 18 of the 21 (86%) patients with localized disease and in none of the patients with diffuse CD (p < .001). The overall survival rate among patients with diffuse CD was significantly lower than that among patients with localized disease (p = .03). CONCLUSION. Diffuse IHBD dilatation with both saccular and fusiform features associated with the peripheral funnel-shaped sign can be used for the diagnosis of CD on MRCP. Localized IHBD dilatation seems to be mainly related to primary intrahepatic lithiasis.

Biliary and duodenal complications after « en bloc¼ liver-small bowel transplantation in children. A single center cohort study.

BACKGROUND: The technique of « en bloc¼ liver and small bowel transplantation (L-BT) spares a biliary anastomosis, but does not protect against biliary complications. We analyze biliary and duodenal complications (BDC) in our pediatric series. METHODS: Between 1994 and 2020, 54 L-BT were performed in 53 children. The procurement technique included in situ vascular dissection and pancreatic reduction to the head until 2009 (group A). Thereafter, the whole pancreas was recovered (group B). RESULTS: Nine BDCs occurred in 8/53 (15%) patients (7 in group A and 1 in group B): leak of the donor's duodenal stump (2), stenosis of the extra-pancreatic bile duct (5), and intra-pancreatic bile duct stenosis (2). Median delay for diagnosis of stricture was 8 months (4-168). Interventional radiology was successful in one child only, the others required reoperations. Two patients died, of biliary cirrhosis or cholangitis, 15-month and 12-year post-L-BT. One was listed and liver re-transplanted 13 years post-L-BT. At last follow-up, two patients only had normal liver tests and ultrasound. CONCLUSION: BDC after L-BT can cause severe morbidities. Pancreatic reduction might increase this risk. Early surgical complications or chronic pancreatic rejection might be co-factors. Early diagnosis and treatment are key to the long-term prognosis.

Practical approach for the diagnosis of biliary atresia on imaging, part 2: magnetic resonance cholecystopancreatography, hepatobiliary scintigraphy, percutaneous cholecysto-cholangiography, endoscopic retrograde cholangiopancreatography, percutaneous liver biopsy, risk scores and decisional flowchart.

We aim to present a practical approach to imaging in suspected biliary atresia, an inflammatory cholangiopathy of infancy resulting in progressive fibrosis and obliteration of extrahepatic and intrahepatic bile ducts. Left untreated or with failure of the Kasai procedure, biliary atresia progresses to biliary cirrhosis, end-stage liver failure and death within the first years of life. Differentiating biliary atresia from other nonsurgical causes of neonatal cholestasis is difficult as there is no single method for diagnosing biliary atresia and clinical, laboratory and imaging features of this disease overlap with those of other causes of neonatal cholestasis. In this second part, we discuss the roles of magnetic resonance (MR) cholecystopancreatography, hepatobiliary scintigraphy, percutaneous biopsy and percutaneous cholecysto-cholangiography. Among imaging techniques, ultrasound (US) signs have a high specificity, although a normal US examination does not rule out biliary atresia. Other imaging techniques with direct opacification of the biliary tree combined with percutaneous liver biopsy have roles in equivocal cases. MR cholecystopancreatography and hepatobiliary scintigraphy are not useful for the diagnosis of biliary atresia. We propose a decisional flowchart for biliary atresia diagnosis based on US signs, including elastography, percutaneous cholecysto-cholangiography or endoscopic retrograde cholangiopancreatography and liver biopsy.

Surveillance of Fontan-associated liver disease: current standards and a proposal from the European Society of Paediatric Radiology Abdominal Task Force.

Since Francis Fontan first introduced the eponymous technique, the Fontan procedure, this type of surgical palliation has allowed thousands of children affected by specific heart malformations to reach adulthood. Nevertheless, abdominal, thoracic, lymphatic and neurologic complications are the price that is paid by these patients. Our review focuses on Fontan-associated liver disease; the purpose is to summarize the current understanding of its physiopathology, the aim of follow-up and the specific radiologic follow-up performed in Europe. Finally, we as members of the Abdominal Task Force of the European Society of Paediatric Radiology propose a consensus-based imaging follow-up algorithm.

Radiologic follow-up in Fontan-associated liver disease in Europe: European Society of Paediatric Radiology survey demonstrates the need for a consensus protocol.

Fontan surgery is a life-saving procedure for newborns with complex cardiac malformations, but it originates complications in different organs. The liver is also affected, with development of fibrosis and sometimes cirrhosis and hepatocellular carcinoma. There is no general agreement on how to follow-up these children for the development of liver disease. To understand the current practice on liver follow-up, we invited members of the European Society of Paediatric Radiology (ESPR) to fill out an online questionnaire. The survey comprised seven questions about when and how liver follow-up is performed on Fontan patients. While we found some agreement on the use of US as screening tool, and of MRI for nodule characterization, the discrepancies on timing and the lack of a shared protocol make it currently impossible to compare data among centers.

Practical approach to imaging diagnosis of biliary atresia, Part 1: prenatal ultrasound and magnetic resonance imaging, and postnatal ultrasound.

We present a practical approach to imaging in suspected biliary atresia, an inflammatory cholangiopathy of infancy resulting in progressive fibrosis and obliteration of extrahepatic and intrahepatic bile ducts. Left untreated or with failure of the Kasai procedure, biliary atresia progresses towards biliary cirrhosis, end-stage liver failure and death by age 3. Differentiation of biliary atresia from other nonsurgical causes of neonatal cholestasis is challenging because there is no single method for diagnosing biliary atresia, and clinical, laboratory and imaging features of this disease overlap with those of other causes of neonatal cholestasis. Concerning imaging, our systematic literature review shows that ultrasonography is the main tool for pre- and neonatal diagnosis. Key prenatal features, when present, are non-visualisation of the gallbladder, cyst in the liver hilum, heterotaxy syndrome and irregular gallbladder walls. Postnatal imaging features have a very high specificity when present, but a variable sensitivity. Triangular cord sign and abnormal gallbladder have the highest sensitivity and specificity. The presence of macro- or microcyst or polysplenia syndrome is highly specific but less sensitive. The diameter of the hepatic artery and hepatic subcapsular flow are less reliable. When present in the context of acholic stools, dilated intrahepatic bile ducts rule out biliary atresia. Importantly, a normal US exam does not rule out biliary atresia. Signs of chronic hepatopathy and portal hypertension (portosystemic derivations such as patent ductus venosus, recanalised umbilical vein, splenomegaly and ascites) should be actively identified for - but are not specific for - biliary atresia.

Establishing local diagnostic reference levels for pediatric percutaneous transhepatic cholangiography interventions and optimizing the routine practice.

BACKGROUND: Liver-transplanted, immunosuppressed pediatric patients undergoing repeated percutaneous transhepatic cholangiography (PTC) require optimized exposure to ionizing radiation. OBJECTIVE: To establish local diagnostic reference levels (DRL) for pediatric PTC and investigate the routine use of X-ray equipment. MATERIALS AND METHODS: The study retrospectively analyzed data collected between October 2016 and June 2018 from a single center performing PTC. We collected exposure parameters including kerma area product (PKA), air kerma at patient entrance reference point (Ka,r) and fluoroscopy time via a dose archiving and communication system. Local diagnostic reference levels were derived as the 50th percentile of the distributions while considering published recommended weight groups. We investigated exposure variability with procedure complexity and with technical parameters recovered from the radiation dose structured report. RESULTS: The analysis included 162 PTC procedures performed in 64 children: 58% male, average age 6 years (range 39 days to 16 years) and weight 24 kg (range 3-60 kg). Local DRLs for weight groups 0-5 kg, 5-15 kg, 15-30 kg, 30-50 kg and 50-80 kg were, respectively, 6 cGy.cm2, 22 cGy.cm2, 68 cGy.cm2, 107 cGy.cm2 and 179 cGy.cm2 in PKA. Local DRLs per weight group were also established for intermediate and complex procedures. Radiation dose structured report analysis highlighted good local practice with efficient collimation, low fluoroscopy pulse rate, no magnification and limited use of radiographic acquisitions. Meanwhile, table and detector positioning and tube projection could still be optimized. PKA correlated significantly with the number of acquisitions and tube-to-table distance. CONCLUSION: We established local DRLs for children undergoing PTC.

European Society of Paediatric Radiology abdominal imaging task force: recommendations for contrast-enhanced ultrasound and diffusion-weighted imaging in focal renal lesions in children.

Contrast-enhanced ultrasound (CEUS) and diffusion-weighted imaging (DWI) are safe, repeatable imaging techniques. The aim of this paper is to discuss the advantages, technical factors and possible clinical applications of these imaging tools in focal renal lesions in children.