Risk factors for renal insufficiency in children with urethral valves.

Posterior urethral valves (PUV) associated with renal dysplasia are one of the most common causes of end stage kidney disease (ESKD) in childhood. In order to identify risk factors for the progression of this condition to early renal failure, we have retrospectively analyzed the clinical course, renal function, and first postnatal renal ultrasound in a sample of 42 young male patients with PUV, who were followed at a single center. Twelve (28.6%) were diagnosed with ESKD at a median age of 11.3 years. Our comparison of PUV patients without decreased estimated glomerular filtration rate (eGFR) (group A; K/DOQI CKD stage 0-1) with PUV patients showing a decreased eGFR (group B; K/DOQI CKD stage 2-5) revealed the following significant risk factors for loss of eGFR: renal volume <3rd percentile (P < 0.001), elevated echogenicity (P = 0.001), pathologic corticomedullary differentiation (P < 0.001), >3 febrile urinary tract infections (P = 0.012), and decreased eGFR at 1 year of age (P < 0.001). Receiver operating characteristic curve analysis in the cohort confirms that patients showing a renal volume >88.2 ml/m(2) body surface area (BSA) are not at risk to develop K/DOQI CKD stage 5 (sensitivity 75%, specificity 77.3%, positive/negative predictive value 37.5/94.4%). Ultrasound promises to be a valuable tool for identifying endangered patients.

Modelling human musculoskeletal functional movements using ultrasound imaging.

BACKGROUND: A widespread and fundamental assumption in the health sciences is that muscle functions are related to a wide variety of conditions, for example pain, ischemic and neurological disorder, exercise and injury. It is therefore highly desirable to study musculoskeletal contributions in clinical applications such as the treatment of muscle injuries, post-surgery evaluations, monitoring of progressive degeneration in neuromuscular disorders, and so on.The spatial image resolution in ultrasound systems has improved tremendously in the last few years and nowadays provides detailed information about tissue characteristics. It is now possible to study skeletal muscles in real-time during activity. METHODS: The ultrasound images are transformed to be congruent and are effectively compressed and stacked in order to be analysed with multivariate techniques. The method is applied to a relevant clinical orthopaedic research field, namely to describe the dynamics in the Achilles tendon and the calf during real-time movements. RESULTS: This study introduces a novel method to medical applications that can be used to examine ultrasound image sequences and to detect, visualise and quantify skeletal muscle dynamics and functions. CONCLUSIONS: This new objective method is a powerful tool to use when visualising tissue activity and dynamics of musculoskeletal ultrasound registrations.

Assessment of skeletal age at the wrist in children with a new ultrasound device.

BACKGROUND: Determination of skeletal development in children is important. The most common method of evaluation uses the standards of Greulich and Pyle (G and P) to assess the left hand radiograph. Numerous assessments may be made during follow-up. OBJECTIVE: The aim of our study was to compare the accuracy of a new sonographic method with the standard radiographic method. MATERIALS AND METHODS: Seventy consecutive patients (age 6-17 years; 34 girls, 36 boys) underwent radiography of the left hand, followed by sonographic examination of the same hand using the BonAge system (Sunlight Medical Ltd., Israel). This system evaluates the relationship between the velocity of sound passing thorough the distal radial and ulna epiphysis and growth, using gender- and ethnicity-based algorithms. One experienced paediatric radiologist analysed the radiograph and assigned bone age scores based on the G and P atlas for the whole left hand and for the distal radius alone. The radiologist was blinded to the chronological age (CA), height of the patient and the BonAge result. Correlation between BonAge and G and P was undertaken. RESULTS: In 65 patients, BonAge measurement could be performed successfully. In five patients, the scanning process was impossible using the ultrasound device. The r(2) (r is the Pearson correlation coefficient) of the BonAge ultrasound measurement and the G and P method was 0.82. The averaged accuracy (i.e. absolute difference in years between G and P reading and BonAge ultrasonic results) was calculated. Results were similar for boys and girls: 1.0+/-0.8 years for the whole left hand and 0.8+/-0.7 year for the distal radius. On average, the difference between BonAge and CA is the same as the difference between G and P and CA, i.e. 1.4 years. CONCLUSIONS: The BonAge device demonstrates the ability of ultrasound to produce an accurate assessment of bone age. The results are highly correlated with skeletal age evaluated conventionally using the G and P method. Obvious advantages of the ultrasound device are objectivity, lack of ionizing radiation, and easy accessibility.

Pediatric brain MRI in neurofibromatosis type I.

Neurofibromatosis (NF) is the most common of the phakomatoses, with a prevalence of 1 in 3-4,000. Many organ systems can be affected. In addition to multiple peripheral neurofibromas, NF I predisposed to CNS tumors including optic glioma, astrocytoma and plexiform neurofibroma. The purpose of this pictorial review is to illustrate characteristic brain MR imaging lesions in children with NF I and to give some recommendations about diagnostic imaging procedures in children suffering from NF I. Typical findings in brain MRI are hyperintense lesion on T2-weighted images, so-called unknown bright objects, which may be useful as an additional imaging criterion for NF I. Contrast administration is necessary in MR studies to maximize tumor detection and characterization, to add confidence to the diagnosis of benign probable myelin vacuolization, and to document stability of neoplasm on follow-up examinations. We recommend to perform serial MR imaging in children every 12 months. The frequency of follow-up in children with known brain tumors will vary with the tumor grade, biological activity and treatment.

The impact of fetal renal pelvic diameter on postnatal outcome.

OBJECTIVES: To determine thresholds for the fetal renal pelvic anterior-posterior diameter (APD) predicting postnatal clinically relevant pelvicaliceal dilatation. METHODS: One hundred and forty-eight infants whose prenatal sonography had identified an isolated uni- or bilateral fetal APD of > or = 4 mm before 33 and/or > or = 7 mm after 33 weeks' gestational age were investigated postnatally. On the basis of postnatal ultrasound examination, these infants were grouped according to the Society for Fetal Urology Grading System: no pelvic dilatation (n = 38); only pelvic dilatation (n = 59); pelvicaliceal dilatation (n = 33); pelvicaliceal and ureter dilatation (n = 18). RESULTS: Fetal pyelectasis of 7 mm was 89.3% sensitive and 78.9% specific < 33 weeks, and > or = 33 weeks pyelectasis of 10 mm was 88.4% and 78.6% in predicting subsequent postnatal pelvicaliectasis, respectively. Using a threshold of 4 mm < 33 weeks and 7 mm > or = 33 weeks yielded a sensitivity of 100% and a specificity of 18.7% and 47.8%, respectively. The median APD (range) at > or = 33 weeks was 19 mm (9-36 mm) in patients requiring surgery and 13 mm (7-21 mm) in conservatively treated patients (p = 0.001). Thirteen of fourteen patients with APD > or = 19 mm underwent surgery. CONCLUSION: Women with ultrasonographically detected prenatal fetal pelvic dilatation of > or = 4 mm before 33 weeks and of > or = 7 mm from 33 weeks onwards of gestation should have repeated prenatal ultrasound scans and a detailed postnatal evaluation. The dilatations of an APD > 4 mm before 33 weeks, which have disappeared at the post-33-week scan need no further investigation in the postnatal period.

High-flow priapism in acute lymphatic leukaemia.

Priapism is defined as prolonged and persistent erection of the penis without sexual stimulation. It is associated with excessive hyperleukocytosis (e.g. in acute or chronic leukaemia); however, this complication is rarely seen in the pediatric population. We report a 12-year-old boy suffering from acute leukaemia presenting with, at first intermittent, but increasingly persistent erection. Doppler US revealed signs of high-flow priapism. MRI excluded intrapelvic tumour masses, and three-dimensional contrast-enhanced MR angiography could not demonstrate an arteriovenous fistula or thrombosis. Cavernosal blood-gas measurement was in agreement with high-flow priapism. On the basis of the imaging findings, invasive therapeutic management was avoided in our patient with a successful outcome.

Electrical impedance scanning-application of this new technique for lymph node evaluation in children.

BACKGROUND: Precise assessment of lymph nodes is crucial to the choice of therapy and prediction of outcome in cases of malignancy. Electrical impedance scanning (EIS) is being experimentally investigated for potential use as a diagnostic tool for differentiation of malignant lesions. Malignancies show different electrical properties with changes in conductivity and capacitance that can be analysed by EIS. Using a TransScan TS-2000 (TransScan Medical, Migdal Ha'Emek, Israel, distributed by Siemens-Elema AB, Solna, Sweden), EIS has been used in various studies for the identification of breast cancer as well as for characterisation of superficial lesions. OBJECTIVE: To evaluate the reliability of EIS for classifying lymph nodes in a pediatric population with sonographically suspicious lesions and to prove its accuracy. MATERIALS AND METHODS: The study population consisted of 77 children (42 boys, 35 girls) aged 1.1-17.1 years. All EIS results were compared to either histopathological findings or long-term follow-up investigations. RESULTS: Sensitivity for malignancies using EIS was 75% and specificity was 87%. The negative predictive value was 93% and the positive predictive value was 60%. CONCLUSIONS: This study suggests the potential usefulness of EIS as an additional imaging modality for the differentiation of lymph-node diseases in children. The histopathological spectrum of malignant lymph node transformation in children compared to studies in adults, and the characteristic meltdown in inflammatory or granulomatous transformed nodes, pose challenges to differentiation based on sonographic evaluation, and also to EIS classification.

US and MRI of gastrointestinal graft-versus-host disease.

Abdominal problems often complicate the clinical course after bone marrow transplantation. Graft-versus-host disease occurs as a complication of allogenic bone marrow transplantation. In this report, the findings of intestinal involvement are described and correlated with histopathological findings. Increased bowel-wall thickness and increased vascularity were shown by US. MRI demonstrated generalised increased bowel-wall thickness associated with bowel-wall enhancement after administration of i.v. gadolinium.

Radiological aspects of the Poland syndrome and implications for treatment: a case study and review.

UNLABELLED: Poland syndrome (PS) (OMIM 173800) is a rare congenital anomaly classically consisting of the combination of unilateral aplasia of the sternocostal head of the major pectoral muscle and an ipsilateral hypoplastic hand with simple syndactyly and short fingers. The aetiology is most probably a vascular disruption sequence of the subclavian arteries. In most cases, PS is sporadic. Familial occurrence suggests that genes exist which are involved in the pathogenesis as paradominant traits. The syndrome may include mammary hypoplasia and further muscle abnormalities which can be accurately defined by sonography and MRI. The evaluation of the vascular status can be performed using colour coded duplex sonography for peripheral arteries and contrast-enhanced MR-angiography for supra-aortic arteries. CONCLUSION: We report a 7-year-old girl with unilateral right sided Poland syndrome with particular emphasis on the radiological investigations of vascular abnormalities. A review of the literature concerning the origin, outcome, and implications for treatment is given.

Voiding urosonography with ultrasonography contrast medium in children.

Voiding urosonography (VUS) with ultrasonography contrast medium is a new modality in the detection of vesicoureteral reflux (VUR) in children. The purpose of this study was to evaluate the diagnostic accuracy of VUS compared with voiding cystourethrography (VCUG) in the detection of VUR. One hundred and eighteen patients, aged 3 weeks to 16 years, with 234 ureterorenal units, were investigated by VUS with ultrasonography contrast medium and radiographic VCUG in one session. The indications were predominantly urinary tract infection and follow-up of previously detected VUR. During the sonographic examination, the bladder was filled with saline solution and an ultrasonography contrast medium (Levovist) was administered through a catheter. Reflux was diagnosed when echogenic bubbles were observed in the ureter or in the renal pelvis. Afterwards, conventional VCUG was performed. Concordant findings were obtained in 210 of 224 ureterorenal units (93.7%). Reflux was excluded by both methods in 174 units (77.7%). With the VCUG as the reference, the sensitivity of VUS was 90%, the specificity 94.6%, the positive predictive value 78.3%, and the negative predictive value 97.8%. The accuracy was 93.7%. In conclusion, VUS with ultrasonography contrast medium is a reliable diagnostic tool for the detection of VUR in children.