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International audience; BACKGROUND:The imaging features of Huntington disease are well known in adults, unlike in juvenile-onset Huntington disease.OBJECTIVE:To conduct a morphometric magnetic resonance imaging (MRI) analysis in three juvenile Huntington disease patients (ages 2, 4 and 6 years old) to determine whether quantitative cerebral and cerebellar morphological metrics may provide diagnostically interesting patterns of cerebellar and cerebellar atrophy.MATERIALS AND METHODS:We report the cases of three siblings with extremely early presentations of juvenile Huntington disease associated with dramatic expansions of the morbid paternal allele from 43 to more than 100 CAG trinucleotide repeats. Automatic segmentation of MRI images of the cerebrum and cerebellum was performed and volumes of cerebral substructures and cerebellar lobules of juvenile Huntington disease patients were compared to those of 30 normal gender- and age-matched controls. Juvenile Huntington disease segmented volumes were compared to those of age-matched controls by using a z-score.RESULTS:Three cerebral substructures (caudate nucleus, putamen and globus pallidus) demonstrated a reduction in size of more than three standard deviations from the normal mean although it was not salient in one of them at clinical reading and was not diagnosed. The size of cerebellum lobules, cerebellum grey matter and cerebellum cortex was reduced by more than two standard deviations in the three patients. The cerebellar atrophy was predominant in the posterior lobe.CONCLUSION:Our study sheds light on atrophic cerebral and cerebellar structures in juvenile Huntington disease. Automatic segmentations of the cerebellum provide patterns that may be of diagnostic interest in this disease.

International audience; BackgroundDiffusion-weighted imaging plays a key role in the imaging of acute pyelonephritis by MRI. However the use of respiratory triggering is challenging and time-consuming in children. Diffusion tensor imaging without respiratory triggering might provide satisfying images of the moving kidneys. Objective To compare mean diffusivity diffusion tensor images obtained with free breathing with diffusion-weighted images obtained with respiratory triggering. Materials and methods Thirty-one children with suspected acute pyelonephritis underwent axial diffusion tensor imaging acquisition with free breathing and axial and coronal diffusion-weighted imaging acquisitions with respiratory triggering. We compared image quality and detection of nephritis between the two sequences. Results Diffusion tensor imaging demonstrated agreement with diffusion-weighted imaging in all cases, with no difference in the detection of nephritis areas. The image quality was significantly better with diffusion tensor imaging (P

Aunque las infecciones urinarias y las uropatias obstructivas son muy frecuentes en la infancia, los estudios por imagen y el momento en que se realizan suelen variar en funcion de las costumbres. Sin embargo, existen recomendaciones internacionales sobre las principales patologias observadas en urorradiologia pediatrica. A veces, estas recomendaciones son divergentes, ya que la mayoria corresponde a consensos de expertos, sin que las conductas sugeridas se basen en pruebas cientificas solidas. Con todo, tienen la ventaja de trazar las lineas principales y permitir estandarizar las practicas. En este articulo se presentan las recomendaciones sobre las tecnicas de estudio por imagen y la conducta frente a la hematuria, la hipertension arterial, las hidronefrosis, las infecciones urinarias, las litiasis y los traumatismos renales. Tambien se describira la fibrosis nefrogenica sistemica.

Reports in uroradiology should be well structured with a systematic description of normal findings and potential pathology. Reports have to be understandable by all physicians who may have to manage children with urologic or nephrologic disorders. To achieve this goal, terms have to be standardized and accepted by the medical community in general. The European Society of Pediatric Radiology uroradiology task force has issued on harmonizing and standardizing uroradiologic terminology in cooperation with European urologists and nephrologists (Vivier PH at al. 2017).

To promote the standardization of nephro-uroradiological terms used in children, the European Society of Paediatric Radiology uroradiology taskforce wrote a detailed glossary. This work has been subsequently submitted to European experts in pediatric urology and nephrology for discussion and acceptance to improve the quality of radiological reports and communication between different clinicians involved in pediatric urology and nephrology.

Congenital anomalies may involve any level of the collecting system; the most usual presentation is urinary tract dilatation that may already be detected during fetal life. The role of imaging is to determine the origin of the dilatation, i.e., obstructive versus nonobstructive (Table 1 lists the causes of urinary tract dilatation). Other useful information includes the level of the impairment to drainage (so-called obstruction) and its impact on renal function. All these data are important in order to determine the best therapeutic approach.

Resume Une malformation veineuse (MV) est une masse des tissus mous frequente de l’enfant, qui ne doit pas etre confondue avec une tumeur vasculaire. Nous rapportons le cas d’un enfant de 10 ans presentant une volumineuse MV thrombosee de l’epaule responsable d’une impotence fonctionnelle douloureuse. Le taux serique de D-dimeres etait augmente. Des phlebolithes, pathognomoniques du diagnostic, ont ete mis en evidence sur la radiographie. L’echo-doppler a confirme la nature veineuse de la lesion et identifie des zones suspectes de thrombose. Dans cette pathologie, l’imagerie par resonance magnetique (IRM) permet d’evaluer l’extension en profondeur et de rechercher des thrombi qui ne sont pas toujours calcifies et dont la mise en evidence est difficile en echographie. Une coagulation intravasculaire localisee, souvent associee a la MV, est a l’origine de ces phenomenes thrombotiques et doit etre confirmee par un dosage des D-dimeres afin de mettre rapidement en route un traitement par heparine de bas poids moleculaire. Le suivi therapeutique comprend un dosage des D-dimeres et eventuellement une IRM pour apprecier l’efficacite de l’anticoagulation et adapter la duree du traitement.

Urinary tract infection (UTI) is very frequent in children. The diagnosis of UTI is based on urinalysis with strict criteria and should not be performed on urine collected by plastic bags due to an unacceptable high rate of false positive. Ultrasound is the cornerstone of UTI imaging in children and should always be performed at the first episode even in case of normal prenatal ultrasound. Doubtful cases or complicated UTI can be explored by MRI. Computed tomography should no longer be performed due to radiation exposure issues unless MRI is unavailable. When to perform voiding cystourethrography remains a subject of debate. Bladder and bowel dysfunction is a major risk of UTI recurrence and should always be considered in toilet-trained children.

Purpose To retrospectively assess supranormal differential renal function (DRF) in unilateral hydronephrotic kidney by functional MR urography (fMRU). Materials and Methods The ethics committees granted exempt status for this study and also waived the need for informed consent. A retrospective analysis was performed of all patients undergoing fMRU from January 2008 to November 2011. DRF was measured by both the area under the curve method and Rutland-Patlak plot. Glomerular DRF per unit of volume and kidney volumes were analyzed. Kidney volumes were compared with nomograms. Results Of 170 children, 3 patients (2, 12, and 14 years) with a left ureteropelvic junction obstruction were included. Glomerular DRF per unit of volume was slightly higher on the dilated side but remained within normal range (

Resume La maladie de Lyme a une incidence tres heterogene en France. Elle est rare dans certaines regions alors qu’elle est tres frequente dans le Centre et l’Est. L’arthrite de Lyme est une manifestation de la phase secondaire de l’infection. Chez l’enfant, le tableau clinique et biologique peut ressembler a celui d’une arthrite septique ou d’une arthrite juvenile idiopathique, beaucoup plus frequentes. Cela explique que le diagnostic soit parfois retarde, surtout si l’on se trouve dans une region ou l’incidence est faible. Nous rapportons le cas d’une fille de 8 ans, traitee pour une arthrite septique du genou dans une region ou la maladie de Lyme est rare. L’evolution clinique et biologique defavorable au 6e j a fait reconsiderer le diagnostic et evoquer une arthrite de Lyme dont le diagnostic a ete confirme par la serologie. Le traitement a ete adapte et l’evolution a rapidement ete favorable. Cette observation rappelle que, chez l’enfant, l’arthrite de Lyme peut mimer une arthrite septique ou une arthrite juvenile idiopathique et qu’il faut toujours savoir l’evoquer, meme dans les regions ou l’incidence est faible.

Established as a method to study anatomic changes, such as renal tumors or atherosclerotic vascular disease, magnetic resonance imaging (MRI) to interrogate renal function has only recently begun to come of age. In this review, we briefly introduce some of the most important MRI techniques for renal functional imaging, and then review current findings on their use for diagnosis and monitoring of major kidney diseases. Specific applications include renovascular disease, diabetic nephropathy, renal transplants, renal masses, acute kidney injury, and pediatric anomalies. With this review, we hope to encourage more collaboration between nephrologists and radiologists to accelerate the development and application of modern MRI tools in nephrology clinics.

To evaluate the performance of diffusion-weighted imaging (DWI) against the reference standard of gadolinium-enhanced T1-weighted imaging (Gd-T1-WI) in children. Thirty-nine consecutive patients (mean age 5.7 years) with suspected acute pyelonephritis underwent magnetic resonance imaging (MRI) including DWI and (the reference standard) Gd-T1-WI. Each study was read in double-blinded fashion by two radiologists. Each kidney was graded as normal or abnormal. Sensitivity and specificity of DWI were computed. Agreement between sequences and interobserver reproducibility were calculated (Cohen κ statistic and the McNemar tests). Thirty-two kidneys (41 %) had hypo-enhancing areas on Gd-T1-W images. The sensitivity and specificity of DWI were 100 % (32/32) and 93.5 % (43/46). DWI demonstrated excellent agreement (κ = 0.92,) with Gd-T1-W, with no significant difference (P = 0.25) in detection of abnormal lesions. Interobserver reproducibility was excellent with DWI (κ = 0.79). DWI enabled similar detection of abnormal areas to Gd-T1-WI and may provide an injection-free means of evaluation of acute pyelonephritis. • Diffusion weighted magnetic resonance imaging (DWI) can confirm acute pyelonepritis. • DWI provided comparable results to gadolinium enhanced T1-W MRI in acute pyelonepritis. • Contrast medium injection could be avoided for diagnosing acute pyelonephritis by MRI. • MRI with T2-WI and DWI provide a fast and comprehensive diagnostic tool.

Objectives The aim of this study was to assess the impact of oral water and intravenous furosemide challenges on blood oxygenation level-dependent magnetic resonance imaging measurements in the kidney and to examine the contribution of R2 (=1/T2) to changes in R2* (=1/T2*). Materials and methods This Health Insurance Portability and Accountability Act-compliant study had institutional review board approval, and written informed consent was obtained from all subjects. Nine healthy volunteers were imaged at 3 T on 2 visits. During each visit, a baseline fasting magnetic resonance acquisition was followed by a diuretic challenge: oral water load for the first visit and furosemide for the second. R2* and R2 values in the renal cortex and medulla were measured using multiple gradient echo and multiple spin echo sequences, respectively, and R2' values were computed as R2' = R2* - R2. Timed urinary output was also measured. Results Averaged across all subjects, the R2* response to furosemide was greater than to water and greater in the medulla than the cortex. The mean R2 responses exhibited the same trends but were uniformly smaller than the mean R2* responses. The peak changes in R2* and R2 appeared, on average, 10 to 14 minutes before peak urinary output. The median percentage contribution of R2 to R2* changes was 16% in the medulla after both challenges. In the cortex, the median contribution was 48% after water load and 58% after furosemide challenge. Conclusions The contributions of R2 to R2* changes after water load and furosemide challenge are not negligible, especially in the renal cortex. In routine clinical practice, R2* could be used alone as a rough surrogate for R2' in the medulla. However, in the cortex, both R2 and R2* should be measured to obtain accurate values of R2'.

Introduction The aim of this study was to evaluate the medium-term results and complications of open inguinal varicocelectomy, including vein ligation, intraoperative venography, and antegrade sclerotherapy. Materials and Methods Sixty-four children were treated between 2000 and 2009 for idiopathic varicocele. Fifty children were examined 6 months after surgery. In 2010, 22 patients were recalled for testicular ultrasound scans (US) to evaluate the medium-term results of the technique. Results The mean age of the children was 12.8 years at first consultation. Of the 50 cases, 35 children were asymptomatic, 13 experienced pain, 3 suffered from discomfort, and 1 had testicular asymmetry. Thirteen children had delayed left testicular growth compared with the right testis. The mean age at surgery was 13.3 years, and follow-up duration was 8.3 months ± 13.9. Thirty-eight patients achieved good results postsurgery; there was varicocele recurrence in 3, testicular hypotrophy in 7, and complete testicular atrophy in 2 patients. Conclusion Naked eye inguinal surgical ligation does not appear to be safe enough to treat young adolescents, with the theoretical risk of a decrease in fertility in the future. In teams which are untrained in microsurgical or laparoscopic varicocelectomy, we suggest referring adolescent patients to a radiologist for embolization.

Resume Introduction Le suivi des enfants handicapes moteurs est particulierement complexe et difficile. L’utilisation d’un dossier medical informatise specialise doit ameliorer l’exhaustivite et la reproductibilite de l’examen clinique de l’appareil locomoteur, faciliter le partage des informations entre cliniciens, et aider a apprecier l’evolution des atteintes orthopediques. Materiel et methodes Pour etre utilisable par la majorite des equipes, ce dossier informatise a ete developpe a partir du logiciel Access™ de la suite Office™ (Microsoft), disponible dans la majorite des centres de soins. Resultats Une fiche d’examen est creee a chaque consultation ou acte therapeutique. Elle recueille les donnees concernant l’examen clinique, le traitement medical, la reeducation, les aides de marche, les injections de toxine botulique, les actes chirurgicaux et les radiographies. Pour etre le plus exhaustif possible, ces fiches sont preremplies avec des menus deroulants et des listes. Elles sont enregistrees dans une base de donnees installee sur un reseau informatique. Ainsi, tous les intervenants peuvent consulter instantanement l’ensemble des donnees depuis n’importe quel ordinateur relie au reseau. En l’absence de reseau, il existe une fonction d’exportation simplifiee des donnees. Un outil calcule les doses, le nombre de flacons necessaires et le prix de revient des injections de toxine botulique selon la toxine utilisee. Des aides integrees ameliorent la reproductibilite de l’examen et servent de support pedagogique. Conclusion Ce dossier informatise de l’examen locomoteur specialise pour les enfants handicapes moteurs est un outil innovant. Il permet d’ameliorer le suivi des patients, la qualite des etudes cliniques et l’enseignement.

At the occasion of the European Society of Paediatric Radiology (ESPR) annual meeting 2015 in Graz, Austria, the newly termed ESPR abdominal (gastrointestinal and genitourinary) imaging task force set out to complete the suggestions for paediatric urogenital imaging and procedural recommendations. Some of the last missing topics were addressed and proposals on imaging of children with anorectal and cloacal malformations and suspected ovarian torsion were issued after intense discussions and a consensus finding process that considered all evidence. Additionally, the terminology was adapted to fit new developments introducing the term pelvicalyceal dilatation/distension (PCD) instead of the sometimes misunderstood hydronephrosis. The present state of paediatric urogenital radiology was discussed in a dedicated minisymposium, including an attempt to adapt terminology to create a standardised glossary.

The ESPR Uroradiology Task Force and the ESUR Paediatric Working Group present two new recommendations on imaging in childhood cystic kidney disease and in childhood renal transplantation, and address the presently restricted availability of contrast-enhanced (ce) US in children. New insights into the genetics require an updated classification of paediatric cystic kidney disease along with a new concept of diagnostic imaging. Characteristic imaging features are key to the new classification. Available recommendations for imaging renal transplantation in children are not satisfactory. The following consensus-based algorithm proposes a more effective and more uniform imaging concept, reducing invasiveness, enhancing diagnostic accuracy, and facilitating future multicentre studies and meta-analysis. At present, ce-US in children can only be performed off-license, since the only approved US contrast agent (CA) for children has been taken off the market. Nevertheless, paediatric ce-US is practiced at multiple places using Sonovue (Bracco, Milan, Italy), a generally available agent in Europe. From a medical and scientific perspective, paediatric ce-US should be promoted, and efforts are undertaken to collect data on paediatric US-CA applications. Routine paediatric imaging depends on local expertise and availability of equipment. The imaging recommendations and supportive data are intended to ease the physicians' difficult task of dealing with the specific diagnostic demands of paediatric paediatric cystic kidney disease and transplantation.

Rationale and Objectives To evaluate intra- and inter-observer variability of right ventricular (RV) functional parameters as evaluated by cardiac magnetic resonance imaging (MRI) in patients with acquired heart disease (AHD), and to identify factors associated with an increased variability. Materials and Methods Sixty consecutive patients were enrolled. Right and left ventricular (LV) volumes, ejection fraction, and mass were determined from short-axis cine sequences. All analyzes were performed twice by three observers with various training-degree in cardiac MRI. Intra- and inter-observer variability was evaluated. The impact on variability of each of the following parameters was assessed: observer's experience, basal and apical slices selection, end-systolic phase selection, and delineation. Results Mean segmentation time ranged 9.8–19.0 minutes for RV and 6.4–9.2 minutes for LV. Variability of RV functional parameters measurement was strongly influenced by previous observer's experience: it was two to three times superior to that of LV, even for the most experienced observer. High variability in the measurement of RV mass was observed. For both ventricles, selection of the basal slice and delineation were major determinants of variability. Conclusion As compared to LV, RV function assessment with cardiac MRI in AHD patients is much more variable and time-consuming. Observer's experience, selection of basal slice, and delineation are determinant.

The kidney performs multiple functions. Glomerular filtration is the most studied of these functions. In clinical practice, the surgical indication for patients with unilateral uropathy is frequently based on the split renal function as demonstrated by scintigraphy. MRI is not yet validated as a technique but nonetheless offers an interesting non-radiating alternative to achieve both morphological and functional renal evaluation. Recent pulse sequences such as diffusion, arterial spin labeling, and blood oxygenation dependent imaging may also provide additional information. CT and US remain of limited value for the evaluation of renal function.

An 11-year-old Caucasian girl was investigated for a clitoromegaly that had increased in size over 5 weeks. Clitoromegaly is a rare condition in childhood. Among nonhormonal causes are tumours, both benign and malignant. Evaluation of the adrenal glands and ovaries was performed by US. An epidermoid cyst was suggested by MRI including diffusion-weighted imaging, and this was confirmed histopathologically.

Un garcon de huit ans a consulte aux urgences pour une douleur exquise a la partie inferoexterne de la jambe droite, sans notion de traumatisme. Ce patient fait du football de facon reguliere. L’examen clinique retrouve un œdeme non inflammatoire de la face externe du tiers inferieur de la jambe droite. Il n’y a pas de syndrome inflammatoire. Des cliches standard (Fig. 1) sont realises puis completes par une IRM (Fig. 2).

To assess prospectively the ability of quantitative low-dose three-dimensional magnetic resonance (MR) renography to help identify the cause of acute graft dysfunction.This HIPAA-compliant study was approved by the institutional review board, and written informed consent was obtained. Between December 2001 and May 2009, sixty patients with transplanted kidneys (41 men and 19 women; mean age, 49 years; age range, 22-71 years) were included. Thirty-one patients had normal function and 29 had acute dysfunction due to acute rejection (n = 12), acute tubular necrosis (ATN) (n = 8), chronic rejection (n = 6), or drug toxicity (n = 3). MR renography was performed at 1.5 T with three-dimensional gradient-echo imaging. With use of a multicompartment renal model, the glomerular filtration rate (GFR) and the mean transit time (MTT) of the tracer for the vascular compartment (MTT(A)), the tubular compartment (MTT(T)), and the collecting system compartment (MTT(C)) were calculated. Also derived was MTT for the whole kidney (MTT(K) = MTT(A) + MTT(T) + MTT(C)) and fractional MTT of each compartment (MTT(A/K) = MTT(A)/MTT(K), MTT(T/K) = MTT(T)/MTT(K), MTT(C/K) = MTT(C)/MTT(K)). These parameters were compared in patients in the different study groups. Statistical analysis was performed by using analysis of covariance.There were significant differences in GFR and MTT(K) between the acute dysfunction group (36.4 mL/min ± 20.8 [standard deviation] and 177.1 seconds ± 46.8, respectively) and the normal function group (65.9 mL/min ± 27.6 and 140.5 seconds ± 51.8, respectively) (P.001 and P = .004). The MTT(A/K) was significantly higher in the acute rejection group (mean, 12.7% ± 2.9) than in the normal function group (mean, 8.3% ± 2.2; P.001) or in the ATN group (mean, 7.1% ± 1.4; P.001). The MTT(T/K) was significantly higher in the ATN group (mean, 83.2% ± 9.2) than in the normal function group (mean, 72.4% ± 10.2; P = .031) or in the acute rejection group (mean, 69.2% ± 6.1; P = .003).Low-dose MR renography analyzed by using a multicompartmental tracer kinetic renal model may help to differentiate noninvasively between acute rejection and ATN after kidney transplantation.

Two new recommendations of the European Society of Radiology task force and the European Society of Uroradiology workgroup on paediatric uroradiology are presented. One deals with diagnostic imaging in children after trauma to the urinary tract-renal trauma, in particular. The other concerns the evaluation of suspected renal hypertension. Available data in the paediatric literature are either unsatisfactory or controversial for both of these clinical settings. Therefore, the following consensus-based proposals aim at outlining effective imaging algorithms to reduce invasive imaging procedures while optimising diagnostic accuracy. The objective of following a more uniform imaging approach is to facilitate future meta-analysis as well as multicentre and other more evidence-based studies. The practise in paediatric radiology is typically based on local availability and on the limitations of professional expertise and equipment, balanced against the perceived needs of the individual child. Although this is unlikely to change in the near future, it does not release the physicians in charge of diagnostic imaging from their responsibility in choosing and providing state-of-the-art imaging and management protocols that are adapted specifically for use in children.

The use of a single exponential function for analysis and variably sampled diffusion weighting plays a substantial role in causing the variability in apparent diffusion coefficient of healthy kidneys.

MR urography (MRU) has been widely accepted as a substitute to intravenous urography for investigating children with a dilated urinary tract after preliminary assessment by US and voiding cystourethrography. Hydronephrosis is by far the main indication for MRU because upper tract dilatation is a frequent condition in infants and children. Recent advances in technology have allowed MR to go beyond morphology and to assess renal function parameters such as split renal function and drainage. In this article we report our routine practice of the F0 MRU technique. The main advantages of our protocol are no requirement for general anaesthesia, no bladder catheterization, use of low-dose gadolinium-based contrast agent (0.05-0.1 mmol/kg) and total acquisition time of 30 min or less.

MR urography (MRU) is an emerging technique particularly useful in paediatric uroradiology. The most common indication is the investigation of hydronephrosis. Combined static and dynamic contrast-enhanced MRU (DCE-MRU) provides both morphological and functional information in a single examination. However, specific post-processing must be performed and to our knowledge, dedicated software is not available in conventional workstations. Investigators involved in MRU classically use homemade software that is not freely accessible. For these reasons, we have developed a software program that is freely downloadable on the National Institute of Health (NIH) website. We report and describe in this study the features of this software program.

Sinonasal cavities: CT imaging features of anatomical variants and surgical risk. MR Urography (MRU) provides both morphologic and functional information without radiation exposure. It enables the assessment of split renal function, excretion, and quantification of obstruction. MRU is thus complementary to ultrasonography in the assessment of pre- and post-natal obstructive uropathies in children. If available, MRU should be definitely preferred to intravenous urography.

Background Sotos syndrome is one the most common overgrowth conditions, after Beckwith-Wiedemann syndrome. As with other overgrowth syndromes, Sotos syndrome can be associated with an increased risk of tumors. Case We describe a young girl with Sotos syndrome and ovarian fibromatosis with a new mutation not reported before in the literature. Summary and Conclusion Development of ovarian tumor in Sotos syndrome has been poorly documented. Ovarian fibromatosis is a very rare non neoplastic disease. Management is guided by the benignity of the lesion and consists of surgical excision of the fibroma.

The aim was to report ultrasound (US) patterns of hepatocyte nuclear factor (HNF1β) mutation throughout childhood and determine whether ultrasound could be predictive of renal failure. The sonographic examinations in 34 children with HNF1β mutation were reviewed. Their sonographic characteristics were compared with renal function. At first postnatal examination renal length was normal in 44 % of the patients, decreased in 24 %, increased in 12 % and asymmetrical in 20 %. Renal cortex was hyperechoic in 97 %. Corticomedullary differentiation was abnormal in 59 %. Cysts were present in 77 % of patients. Cysts were mostly subcapsular (64 %). Twenty-eight patients had follow-up examinations. A modification of the sonographic appearance was observed in 91 % of patients. Eight patients (23 %) had renal failure; no specific US pattern could be demonstrated. At birth, HNF1β mutation was typically associated on US with the combination of hyperechoic, normal-sized kidneys with abnormal corticomedullary differentiation (CMD) and multiple cortical cysts. In older children, the appearances can be variable: kidneys may have decreased (32 %) or normal size (33 %); they are usually hyperechoic (50 %) with abnormal CMD (78 %) and (sub)cortical cysts (71 %). No pattern appears to be associated with renal failure. • HNF1β mutations determine significant anomalies of sonographic appearances of kidneys in children. • Kidneys appear mainly hyperechoic, with or without CMD and with subcapsular cysts. • The US pattern may evolve throughout childhood in the same patient. • No correlation was found between any sonographic pattern and renal failure.

The European Society of Paediatric Radiology Uroradiology Task Force and the ESUR Paediatric Work Group jointly publish guidelines for paediatric urogenital imaging. Two yet unaddressed topics involving patient safety and imaging load are addressed in this paper: renal biopsy in childhood and imaging of the neonatal genital tract, particularly in girls. Based on our thorough review of literature and variable practice in multiple centers, procedural recommendations are proposed on how to perform renal biopsy in children and how to approach the genital tract in (female) neonates. These are statements by consensus due to lack of sufficient evidence-based data. The procedural recommendation on renal biopsy in childhood aims at improving patient safety and reducing the number of unsuccessful passes and/or biopsy-related complications. The recommendation for an imaging algorithm in the assessment of the neonatal genital tract focuses on the potential of ultrasonography to reduce the need for more invasive or radiating imaging, however, with additional fluoroscopy or MRI to be used in selected cases. Adherence to these recommendations will allow comparable data and evidence to be generated for future adaptation of imaging strategies in paediatric uroradiology.

To assess the reproducibility and the distribution of intravoxel incoherent motion (IVIM) and diffusion-tensor (DT) imaging parameters in healthy renal cortex and medulla at baseline and after hydration or furosemide challenges.Using an institutional review board-approved HIPAA-compliant protocol with written informed consent, IVIM and DT imaging were performed at 3 T in 10 volunteers before and after water loading or furosemide administration. IVIM (apparent diffusion coefficient [ADC], tissue diffusivity [D(t)], perfusion fraction [f(p)], pseudodiffusivity [D(p)]) and DT (mean diffusivity [MD], fractional anisotropy [FA], eigenvalues [λ(i)]) imaging parameters and urine output from serial bladder volumes were calculated. (a)Reproducibility was quantified with coefficient of variation, intraclass correlation coefficient, and Bland-Altman limits of agreement; (b) contrast and challenge response were quantified with analysis of variance; and (c) Pearson correlations were quantified with urine output.Good reproducibility was found for ADC, D(t), MD, FA, and λ(i) (average coefficient of variation, 3.7% [cortex] and 5.0% [medulla]), and moderate reproducibility was found for D(p), f(p), and f(p) · D(p) (average coefficient of variation, 18.7% [cortex] and 25.9% [medulla]). Baseline cortical diffusivities significantly exceeded medullary values except D(p), for which medullary values significantly exceeded cortical values, and λ(1,) which showed no contrast. ADC, D(t), MD, and λ(i) increased significantly for both challenges. Medullary diffusivity increases were dominated by transverse diffusion (1.72 ± 0.09 [baseline] to 1.79 ± 0.10 [hydration] μm(2)/msec, P = .0059; or 1.86 ± 0.07 [furosemide] μm(2)/msec, P = .0094). Urine output correlated with cortical ADC with furosemide (r = 0.7, P = .034) and with medullary λ(1) (r = 0.83, P = .0418), λ(2) (r = 0.85, P = .0301), and MD (r = 0.82, P = .045) with hydration.Diffusion MR metrics are sensitive to flow changes in kidney induced by diuretic challenges. The results of this study suggest that vascular flow, tubular dilation, water reabsorption, and intratubular flow all play important roles in diffusion-weighted imaging contrast.

To retrospectively assess supranormal differential renal function (DRF) in unilateral hydronephrotic kidney by functional MR urography (fMRU).The ethics committees granted exempt status for this study and also waived the need for informed consent. A retrospective analysis was performed of all patients undergoing fMRU from January 2008 to November 2011. DRF was measured by both the area under the curve method and Rutland-Patlak plot. Glomerular DRF per unit of volume and kidney volumes were analyzed. Kidney volumes were compared with nomograms.Of 170 children, 3 patients (2, 12, and 14 years) with a left ureteropelvic junction obstruction were included. Glomerular DRF per unit of volume was slightly higher on the dilated side but remained within normal range (55%). Dilated kidney volumes were higher on the dilated side (≥55%). The volumes of nondilated kidneys were within normal range.The data support the fact that the dilated kidney was not hyperfunctioning and that the nondilated kidney was not hypofunctioning. Based on these three patients, it could be assumed that supranormal DRF on the dilated side might be explained by a slight kidney volume asymmetry, in association with higher DRF per unit of volume, remaining within normal physiological range. J. Magn. Reson. Imaging 2014;40:577-582. © 2013 Wiley Periodicals, Inc.

To evaluate intra- and inter-observer variability of right ventricular (RV) functional parameters as evaluated by cardiac magnetic resonance imaging (MRI) in patients with acquired heart disease (AHD), and to identify factors associated with an increased variability.Sixty consecutive patients were enrolled. Right and left ventricular (LV) volumes, ejection fraction, and mass were determined from short-axis cine sequences. All analyzes were performed twice by three observers with various training-degree in cardiac MRI. Intra- and inter-observer variability was evaluated. The impact on variability of each of the following parameters was assessed: observer's experience, basal and apical slices selection, end-systolic phase selection, and delineation.Mean segmentation time ranged 9.8-19.0 minutes for RV and 6.4-9.2 minutes for LV. Variability of RV functional parameters measurement was strongly influenced by previous observer's experience: it was two to three times superior to that of LV, even for the most experienced observer. High variability in the measurement of RV mass was observed. For both ventricles, selection of the basal slice and delineation were major determinants of variability.As compared to LV, RV function assessment with cardiac MRI in AHD patients is much more variable and time-consuming. Observer's experience, selection of basal slice, and delineation are determinant.

International audience; OBJECTIVES: To evaluate the diagnostic accuracy and variability of 3 semi-quantitative (SQt) methods for assessing right ventricular (RV) systolic function from cardiac MRI in patients with acquired heart disease: tricuspid annular plane systolic excursion (TAPSE), RV fractional-shortening (RVFS) and RV fractional area change (RVFAC). METHODS: Sixty consecutive patients were enrolled. Reference RV ejection fraction (RVEF) was determined from short axis cine sequences. TAPSE, RVFS and RVFAC were measured on a 4-chamber cine sequence. All SQt analyses were performed twice by 3 observers with various degrees of training in cardiac MRI. Correlation with RVEF, intra- and inter-observer variability, and receiver operating characteristic (ROC) curve analysis were performed for each SQt method. RESULTS: Correlation between RVFAC and RVEF was good for all observers and did not depend on previous cardiac MRI experience (R range = 0.716-0.741). Conversely, RVFS (R range = 0.534-0.720) and TAPSE (R range = 0.482-0.646) correlated less with RVEF and depended on previous experience. Intra- and inter-observer variability was much lower for RVFAC than for RVFS and TAPSE. ROC analysis demonstrated that RVFAC

To assess the accuracy of glomerular filtration rate (GFR) measurements obtained with low-contrast agent dose dynamic contrast material-enhanced magnetic resonance (MR) renography in patients with liver cirrhosis who underwent routine liver MR imaging, with urinary clearance of technetium 99m ((99m)Tc) pentetic acid (DTPA) as the reference standard.This HIPAA-compliant study was institutional review board approved. Written informed patient consent was obtained. Twenty patients with cirrhosis (14 men, six women; age range, 41-70 years; mean age, 54.6 years) who were scheduled for routine 1.5-T liver MR examinations to screen for hepatocellular carcinoma during a 6-month period were prospectively included. Five-minute MR renography with a 3-mL dose of gadoteridol was performed instead of a routine test-dose timing examination. The GFR was estimated at MR imaging with use of two kinetic models. In one model, only the signal intensities in the aorta and kidney parenchyma were considered, and in the other, renal cortical and medullary signal intensities were treated separately. The GFR was also calculated by using serum creatinine levels according to the Cockcroft-Gault and modification of diet in renal disease (MDRD) formulas. All patients underwent a (99m)Tc-DTPA urinary clearance examination on the same day to obtain a reference GFR measurement. The accuracies of all MR- and creatinine-based GFR estimations were compared by using Wilcoxon signed rank tests.The mean reference GFR, based on (99m)Tc-DTPA clearance, was 74.9 mL/min/1.73 m(2) ± 27.7 (standard deviation) (range, 10.3-120.7 mL/min/1.73 m(2)). With both kinetic models, 95% of MR-based GFRs were within 30% of the reference values, whereas only 40% and 60% of Cockcroft-Gault- and MDRD-based GFRs, respectively, were within this range. MR-based GFR estimates were significantly more accurate than creatinine level-based estimates (P.001).GFR assessment with MR imaging, which outperformed the Cockcroft-Gault and MDRD formulas, adds less than 10 minutes of table time to a clinically indicated liver MR examination without ionizing radiation.http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11101338/-/DC1.

We report a case of Herlyn-Werner-Wunderlich syndrome diagnosed in the neonatal period. US revealed the classic association of a uterus didelphys with blind hemivagina and no ipsilateral kidney. The diagnosis was established by postnatal US and confirmed by MRI. Differential diagnoses are discussed. A trans-hymeneal resection of the vaginal septum was performed at 1 month of age. Intra operative endoscopy revealed no left hemitrigone but showed an atretic orifice in the ipsilateral blind hemivagina, probably corresponding to the insertion of an ectopic ureter. Follow-up was unremarkable.

Polycystic kidney disease (PKD) is a disorder characterized by the growth of numerous fluid filled cysts in the kidneys. Measuring cystic kidney volume is thus crucial to monitoring the evolution of the disease. While T2-weighted MRI delineates the organ, automatic segmentation is very difficult due to highly variable shape and image contrast. The interactive stereology methods used currently involve a compromise between segmentation accuracy and time. We have investigated semi-automated methods: active contours and a sub-voxel morphology based algorithm. Coronal T2- weighted images of 17 patients were acquired in four breath-holds using the HASTE sequence on a 1.5 Tesla MRI unit. The segmentation results were compared to ground truth kidney masks obtained as a consensus of experts. Automatic active contour algorithm yielded an average 22% ± 8.6% volume error. A recently developed method (Bridge Burner) based on thresholding and constrained morphology failed to separate PKD from the spleen, yielding 37.4% ± 8.7% volume error. Manual post-editing reduced the volume error to 3.2% ± 0.8% for active contours and 3.2% ± 0.6% for Bridge Burner. The total time (automated algorithm plus editing) was 15 min ± 5 min for active contours and 19 min ± 11 min for Bridge Burner. The average volume errors for stereology method were 5.9%, 6.2%, 5.4% for mesh size 6.6, 11, 16.5 mm. The average processing times were 17, 7, 4 min. These results show that nearly two-fold improvement in PKD segmentation accuracy over stereology technique can be achieved with a combination of active contours and postediting.

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The patient, 23-year-old man, was known to have tuberous sclerosis (TS). He had been previously diagnosed with renal angiomyolipomas ( Panel A ), and intracranial lesions. He had neither cardiac, nor pulmonary symptoms. Since TS can involve various organs, a chest and abdominal multi detector computed tomography was performed. It incidentally revealed …

International audience; OBJECTIVE: Renal volumetry is an essential part of split renal function assessment in MR urography. The aim of this study was to assess the accuracy and repeatability of a 3D segmentation algorithm based on the belief functions theory for calculating renal volumes from MR images. MATERIALS AND METHODS: The true volumes of 20 animal kidneys of various sizes were obtained by fluid displacement. Each kidney was examined using two different MR units. Three-dimensional proton density-weighted acquisitions with an incremental slice thickness were performed. The MR volume was then measured with a segmentation algorithm based on the belief functions theory. Two independent observers performed all segmentations twice. Accuracy, intraobserver variability, and interobserver variability were evaluated by the Bland-Altman method. The number and type of manual corrections were recorded as well as the entire processing time. RESULTS: The mean renal volume estimated by fluid displacement was 114 mL (range, 38-224 mL). With regard to the renal volumes obtained from assessments of adjacent axial MR images, the maximal SDs of the difference were 2.2 mL (accuracy), 0.6 mL (intraobserver variability), and 1.8 mL (interobserver variability). Segmentation of axial slices provided better accuracy and reproducibility than coronal slices. Overlapped coronal slices yielded poor results because of the partial volume effect. The mean processing time including optional manual modifications was less than 75 seconds. CONCLUSION: The belief functions theory can be considered an accurate and reproducible mathematic method to assess renal volume from MR adjacent images.