Whole-body MR imaging in suspected physical child abuse: comparison with skeletal survey and bone scintigraphy findings from the PEDIMA prospective multicentre study.

OBJECTIVES: To assess the contribution of whole-body magnetic resonance imaging (WBMRI) and bone scintigraphy (BS) in addition to skeletal survey (SS) in detecting traumatic bone lesions and soft-tissue injuries in suspected child abuse. METHODS: In this prospective, multicentre, diagnostic accuracy study, children less than 3 years of age with suspected physical abuse were recruited. Each child underwent SS, BS and WBMRI. A blinded first review was performed in consensus by five paediatric radiologists and three nuclear medicine physicians. A second review investigated discrepancies reported between the modalities using a consensus result of all modalities as the reference standard. We calculated the sensitivity, specificity and corresponding 95% confidence interval for each imaging modality (SS, WBMRI and BS) and for the combinations [SS + WBMRI] and [SS + BS]. RESULTS: One hundred seventy children were included of which sixty-four had at least one lesion. In total, 146 lesions were included. The sensitivity and specificity of each examination were, respectively, as follows: 88.4% [95% CI, 82.0-93.1] and 99.7% [95% CI, 99.5-99.8] for the SS, 69.9% [95% CI, 61.7-77.2] and 99.5% [95% CI, 99.2-99.7] for WBMRI and 54.8% [95% CI, 46.4-63.0] and 99.7% [95% CI, 99.5-99.9] for BS. Sensitivity and specificity were, respectively, 95.9% [95% CI, 91.3-98.5] and 99.2% [95% CI, 98.9-99.4] for the combination SS + WBMRI and 95.2% [95% CI, 90.4-98.1] and 99.4% [95% CI, 99.2-99.6] for the combination SS + BS, with no statistically significant difference between them. CONCLUSION: SS was the most sensitive independent imaging modality; however, the additional combination of either WBMRI or BS examinations offered an increased accuracy. KEY POINTS: • SS in suspected infant abuse was the most sensitive independent imaging modality in this study, especially for detecting metaphyseal and rib lesions, and remains essential for evaluation. • The combination of either SS + BS or SS + WBMRI provides greater accuracy in diagnosing occult and equivocal bone injuries in the difficult setting of child abuse. • WBMRI is a free-radiation technique that allows additional diagnosis of soft-tissue and visceral injuries.

Morphological features in juvenile Huntington disease associated with cerebellar atrophy - magnetic resonance imaging morphometric analysis.

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.

Diffusion tensor imaging in acute pyelonephritis in children.

BACKGROUND: Diffusion-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<0.01). CONCLUSION: Diffusion tensor imaging could replace diffusion-weighted imaging for diagnosis of acute pyelonephritis.

Standardization of pediatric uroradiological terms: a multidisciplinary European glossary.

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.

Standardization of pediatric uroradiological terms: A multidisciplinary European glossary.

To promote the standardization of nephro-uroradiological terms used in children, the European Society of Pediatric 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 among different clinicians involved in pediatric urology and nephrology.

European Society of Paediatric Radiology abdominal imaging task force recommendations in paediatric uroradiology, part IX: Imaging in anorectal and cloacal malformation, imaging in childhood ovarian torsion, and efforts in standardising paediatric uroradiology terminology.

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.

Renal involvement in children with HNF1ß mutation: early sonographic appearances and long-term follow-up.

OBJECTIVES: The aim was to report ultrasound (US) patterns of hepatocyte nuclear factor (HNF1ß) mutation throughout childhood and determine whether ultrasound could be predictive of renal failure. METHODS: The sonographic examinations in 34 children with HNF1ß mutation were reviewed. Their sonographic characteristics were compared with renal function. RESULTS: 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. CONCLUSIONS: At birth, HNF1ß 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. KEY POINTS: • HNF1ß 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.

Supranormal differential renal function in unilateral hydronephrotic kidney: insights from functional MR urography.

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 (<55%). Dilated kidney volumes were higher on the dilated side (≥55%). The volumes of nondilated kidneys were within normal range. CONCLUSION: 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.

ESPR uroradiology task force and ESUR Paediatric Work Group--Imaging recommendations in paediatric uroradiology, part VI: childhood renal biopsy and imaging of neonatal and infant genital tract. Minutes from the task force session at the annual ESPR Meeting 2012 in Athens on childhood renal biopsy and imaging neonatal genitalia.

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.

Measurement of renal tissue oxygenation with blood oxygen level-dependent MRI and oxygen transit modeling.

Blood oxygen level-dependent (BOLD) MRI data of kidney, while indicative of tissue oxygenation level (Po2), is in fact influenced by multiple confounding factors, such as R2, perfusion, oxygen permeability, and hematocrit. We aim to explore the feasibility of extracting tissue Po2 from renal BOLD data. A method of two steps was proposed: first, a Monte Carlo simulation to estimate blood oxygen saturation (SHb) from BOLD signals, and second, an oxygen transit model to convert SHb to tissue Po2. The proposed method was calibrated and validated with 20 pigs (12 before and after furosemide injection) in which BOLD-derived tissue Po2 was compared with microprobe-measured values. The method was then applied to nine healthy human subjects (age: 25.7 ± 3.0 yr) in whom BOLD was performed before and after furosemide. For the 12 pigs before furosemide injection, the proposed model estimated renal tissue Po2 with errors of 2.3 ± 5.2 mmHg (5.8 ± 13.4%) in cortex and -0.1 ± 4.5 mmHg (1.7 ± 18.1%) in medulla, compared with microprobe measurements. After injection of furosemide, the estimation errors were 6.9 ± 3.9 mmHg (14.2 ± 8.4%) for cortex and 2.6 ± 4.0 mmHg (7.7 ± 11.5%) for medulla. In the human subjects, BOLD-derived medullary Po2 increased from 16.0 ± 4.9 mmHg (SHb: 31 ± 11%) at baseline to 26.2 ± 3.1 mmHg (SHb: 53 ± 6%) at 5 min after furosemide injection, while cortical Po2 did not change significantly at ∼58 mmHg (SHb: 92 ± 1%). Our proposed method, validated with a porcine model, appears promising for estimating tissue Po2 from renal BOLD MRI data in human subjects.

New magnetic resonance imaging methods in nephrology.

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.

MRI and suspected acute pyelonephritis in children: comparison of diffusion-weighted imaging with gadolinium-enhanced T1-weighted imaging.

OBJECTIVES: To evaluate the performance of diffusion-weighted imaging (DWI) against the reference standard of gadolinium-enhanced T1-weighted imaging (Gd-T1-WI) in children. METHODS: 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). RESULTS: 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). CONCLUSION: DWI enabled similar detection of abnormal areas to Gd-T1-WI and may provide an injection-free means of evaluation of acute pyelonephritis. KEY POINTS: • 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.

Idiopathic varicocele in adolescents: risks of the inguinal approach.

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.

Renal blood oxygenation level-dependent imaging: contribution of R2 to R2* values.

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'.

ESPR Uroradiology Task Force and ESUR Paediatric Working Group--Imaging recommendations in paediatric uroradiology, part V: childhood cystic kidney disease, childhood renal transplantation and contrast-enhanced ultrasonography in children.

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.

Cardiac MRI assessment of right ventricular function in acquired heart disease: factors of variability.

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.

Intravoxel incoherent motion and diffusion-tensor imaging in renal tissue under hydration and furosemide flow challenges.

PURPOSE: 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. MATERIALS AND METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Imaging of a primitive clitoral epidermoid cyst.

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.

Quantitative evaluation of acute renal transplant dysfunction with low-dose three-dimensional MR renography.

PURPOSE: To assess prospectively the ability of quantitative low-dose three-dimensional magnetic resonance (MR) renography to help identify the cause of acute graft dysfunction. MATERIALS AND METHODS: 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. RESULTS: 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). CONCLUSION: 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.

Uterus didelphys, hemihydrocolpos and empty ipsilateral lumbar fossa in a newborn girl: involuted dysplastic kidney rather than renal agenesis.

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.