[Imaging of hepatic tumors in children and adolescents]. / Bildgebung von Lebertumoren im Kindes- und Jugendalter.

BACKGROUND: Pediatric liver tumors are relatively rare, but thorough knowledge of their imaging features is still important. OBJECTIVES: Frequency and imaging features of benign and malignant liver masses during childhood and adolescence. MATERIALS AND METHODS: Discussion of relevant original articles, review manuscripts and expert recommendations concerning imaging of childhood liver tumors. RESULTS: The most common malignant tumors of the liver are hepatoblastoma, which usually occur in younger children, as well as in some regions hepatocellular carcinoma. In contrast to most benign masses, such as focal nodular hyperplasia, simple cysts or fatty liver infiltrations, their imaging morphology is not very characteristic. Radiologically, sonography and magnetic resonance imaging (MRI) are used for assessment. Both methods benefit from intravenous contrast agent administration. CONCLUSIONS: Childhood liver tumors show a broad spectrum of morphological manifestations. Some entities can be characterized using standard imaging, some require multimodal imaging or histological assessment. In addition to morphological imaging criteria, age and the medical history as well as laboratory data play an important role in establishing the correct diagnosis.

[Urinary tract infections in children]. / Harnwegsinfekte bei Kindern.

Urinary tract infections (UTI) are the most common bacterial infections in children. The symptoms are not very specific and range from abdominal pain, poor feeding to nocturnal urinary incontinence. The technique of collecting urine plays an important role for securing the diagnosis. The best way to obtain urine in non-toilet-trained children is catheterization or suprapubic bladder aspiration. In toilet-trained children midstream urine is an acceptable alternative after cleaning the foreskin or labia. In the case of an infection a prompt empirical antibiotic therapy is necessary to reduce the risk of parenchymal scarring of the kidneys. There are different approaches to diagnose vesicoureteral reflux in different countries. The commonly used standard approach in Germany is voiding cystourethrography. In the case of reflux dimercaptosuccinic acid (DMSA) scintigraphy should be performed additionally to exclude renal scarring (bottom-up approach).

[Pediatric outpatient surgery]. / Ambulantes Operieren im Kindesalter.

BACKGROUND: The number of outpatient surgeries for routine surgical interventions continues to increase, especially in adults. For many patients, there is no doubt that interventions like arthroscopy will be performed on an outpatient basis. Regarding urologic surgeries in adults (e.g., vasectomy, hydrecelectomy), outpatient treatment is well established. For adults such a procedure represents a well-calculable situation in most cases, as the patient can quite accurately imagine the events that will follow. In terms of pediatric outpatient surgery, the scenario is sometimes quite different. Parents are more anxious and uncertain because they must decide for the well-being of their children and they often do not exactly know what will happen during the procedure. In addition, they do not have to decide for themselves but for their children. DISCUSSION: Unfortunately, parents often lack information prior to surgery. Therefore, all persons involved in the treatment of children (e.g., urologists, anesthesiologists, nurses) must be trained and educated in giving adequate and appropriate information especially for parents. CONCLUSION: The purpose of this article is to provide different starting points for an optimized preparation and care of children and parents concerning outpatient surgery in pediatric urology.

[Vesico-ureteral reflux: Diagnosis and treatment recommendations]. / Vesikoureteraler Reflux : Diagnose und Therapieempfehlungen.

BACKGROUND: Vesico-ureteral reflux (VUR) is one of the most common urologic diseases in childhood. About every third child that presents with a urinary tract infection (UTI) has urinary reflux to the ureter or kidney. Demonstration of a backflow of urine into the ureters or kidneys proves vesicoureteral reflux. In unclear cases, a positioned instillation of contrast agent (PIC) cystogram might be performed and is able to prove vesico-ureteral reflux. OBJECTIVES: Since low-grade VUR has a high probability of maturation and self-limitation, infants with VUR should be given prophylactic antibiotics during their first year of life, reevaluating the status of VUR after 12 months. The aim of any treatment is to prevent renal damage. THERAPY: The individual risk of renal scarring is decisive for the choice of adequate therapy. This risk is mainly dependent on reflux grade, age, and gender of the child as well as parental therapy adherence. In principle, therapeutic options include conservative as well as endoscopic or open surgical antireflux therapies. CONCLUSION: Decisions on treatment should be made individually with parents taking into account all the findings available.

[Imaging in pediatric urology]. / Bildgebung in der Kinderurologie.

BACKGROUND: For many years, sonography and the intravenous pyelogram (IVP) were the most important examination methods for the evaluation of the urinary tract in children. Both methods have their pros and cons: sonography provides ideal visualization of normal kidneys and the evaluation of the pelvicalyceal system. For detection or exclusion of renal scarring, however, this method is not well suited. It provides no information regarding kidney function. METHODS: With an IVP, it is possible to evaluate urinary excretion and, thus, indirectly assess kidney function. As this examination method involves radiation exposure and the necessity of a contrast agent, it should be avoided in the examination of children. The CT is an excellent examination method that can diagnose nearly all urological diseases in children or answer urological questions; however, a CT scan applies the highest radiation dose of all discussed methods. For this reason, examination via MRI is of increasing importance in uroradiology. Initially only the T2 sequences for the visualization of the urinary tract in children were applied. CONCLUSION: The current technical developments as well as the use of the contrast agent gadolinium and the antidiuretic agent furosemide allow an all-in-one evaluation of the kidneys and urinary tract.

[Management of hypospadias]. / Management der Hypospadie.

Hypospadias are diagnosed at birth. Counseling of the parents should be performed in detail. Isolated hypospadias has to be differentiated from disorders of sexual development which are mostly associated with cryptorchidism and micropenis. The operation is timed around the first birthday. Preoperative hormonal treatment should be reserved for infants with a small glans penis or for repeat surgery. The most popular method in distal hypospadias repair is preservation of the urethral plate and tubularization with or without midline incision. In proximal cases with severe curvature a two-stage procedure may be preferable. Dripping-stent urinary drainage into a double diaper is the best method in infants. The complication rate after primary distal repair is reported in the literature to be less than 10% and after staged procedures in proximal hypospadias over 25%.

CT in children--dose protection and general considerations when planning a CT in a child.

Today CT represents about 10% of all ionizing radiation based imaging modalities, but delivers more than 50% of the total collective dose for diagnostic imaging. Compared to adults the radiation sensitivity of children is considerable higher than in adults. Additionally children differ from adults--factors like body size, mass, density, proportions as well as metabolism have to be mentioned. Children grow and mature--all this components have to be mapped in examination protocols by Pediatric Radiology. The total dose of a CT examination depends on the settings of several factors such as the scout view, the scan length, exposure settings including automated exposure control, type of scanning (single slice, helical, volume mode), slice thickness, pitch values as well as on image reconstruction parameters. If intravenous contrast media injection is needed bolus tracking or timing represents another source of radiation. The aim of the paper is to present and discuss all aspects of defining a pediatric age and query adapted CT protocol particularly concerning all dose relevant factors in pediatric CT and their adjustment in children. Moreover hints are given concerning optimization of intravenous contrast media injection as well as special (low dose) imaging protocols.

Experience with volumetric (320 rows) pediatric CT.

The introduction of helical computer tomography (CT) and further progress to multi-slice CT enabled new applications. Most recent developments like the 320-row detector facilitate volume CT, which avoids the over-beaming effect of helical scanning. The 320-row multi-slice detector CT (MDCT) is based on a 16cm detector; a special acquisition mode allows reconstructing 640 slices from these 16cm. The shortest tube rotation time is in cardiac mode 0.35s, otherwise 0.4s and 0.5s used. At 0.5s the machine already reaches the maximum numbers of sub-second projections. Scan modes can be volume, helical and single slice mode. For image acquisition all dose savings technologies like variable tube position for scano-view, active collimation, automated exposure control, bolus and ECG tracking are available. Additionally special acquisition and post-processing techniques like head and body perfusion CT are ready for use on the console. For image reconstruction properties like filtered back projection as well as the latest development of iterative algorithms, an appropriate number of kernels and multi-planar reconstruction in all directions from the volume data at every increment are available. Volume CT allows sub second scanning of 16cm z-coverage which, however, makes administration of intravenous contrast medium to "hit or miss" event. The aim of this paper is to present the application of volume CT to body scanning in children. Representative examples of neck, cardiac and skeletal investigations are given.

Multi-detector CT in the paediatric urinary tract.

The use of paediatric multi-slice CT (MSCT) is rapidly increasing worldwide. As technology advances its application in paediatric care is constantly expanding with an increasing need for radiation dose control and appropriate utilization. Recommendations on how and when to use CT for assessment of the paediatric urinary tract appear to be an important issue. Therefore the European Society of Paediatric Radiology (ESPR) uroradiology task force and European Society of Urogenital Radiology (ESUR) paediatric working groups created a proposal for performing renal CT in children that has recently been published. The objective of this paper is to discuss paediatric urinary tract CT (uro-CT) in more detail and depth. The specific aim is not only to offer general recommendations on clinical indications and optimization processes of paediatric CT examination, but also to address various childhood characteristics and phenomena that facilitate understanding the different approach and use of uro-CT in children compared to adults. According to ALARA principles, paediatric uro-CT should only be considered for selected indications provided high-level comprehensive US is not conclusive and alternative non-ionizing techniques such as MR are not available or appropriate. Optimization of paediatric uro-CT protocols (considering lower age-adapted kV and mAs) is mandatory, and the number of phases and acquisition series should be kept as few as possible.

Perfusion CT in childhood stroke--initial observations and review of the literature.

INTRODUCTION: To report the preliminary results of contrast-enhanced perfusion multi-detector CT for diagnoses of perfusion disturbances in children with clinical suspicion of stroke. PATIENTS AND METHODS: Within the last two years emergency perfusion CT was performed in ten children (age: 8-17 years, male:female=3:7) for assessment of suspected childhood stroke. These intracranial perfusion CT, intracranial CT-digital subtraction angiography (CT-DSA) and extracranial CT-angiography (CTA) studies were retrospectively reviewed and compared with MRI, follow-up CT, catheter angiography and final clinical diagnosis. The total dose length product (DLP) for the entire examination was recorded. The image quality of perfusion CT-maps, CT-DSA and CTA were evaluated with a subjective three-point scale ranging from very good to non-diagnostic image quality rating perfusion disturbance, intracranial peripheral vessel depiction, and motion- or streak artifacts. RESULTS: In nine of ten children perfusion CT showed no false positive or false negative results. In one of ten children suffering from migraine focal hypo-perfusion was read as perfusion impairment potentially indicating early stroke, but MRI and MRA follow-up were negative. Overall, perfusion-CT with CT-DSA was rated very good in 80% of cases for the detection of perfusion disturbances and vessel anatomy. CONCLUSIONS: In comparison to standard CT, contrast-enhanced perfusion CT improves CTs' diagnostic capability in the emergency examination of children with a strong suspicion of ischemic cerebral infarction.

[Current trends in the management of primary hypospadias: indication for surgery and surgical goal]. / Aktuelle Trends in der Behandlung primärer Hypospadien: Operationsindikation und Operationsziel.

The therapeutic goal of surgical correction of hypospadias is the reconstruction of the primary malformation into a normal penis. Nowadays the operation is timed around the first birthday of the infant. The procedure is performed in different operative steps depending on the individual components to hypospadias. The current trend is to preserve and tubularize the urethral plate and to stage the procedure in proximal hypospadias with severe chordee. The perioperative management includes modern paediatric anaesthesia methods in combination with regional anaesthesia, urinary drainage into a double diaper and to waive the fixation of the baby at the bed.

High resolution MR for evaluation of lower urogenital tract malformations in infants and children: feasibility and preliminary experiences.

INTRODUCTION: This retrospective study aimed to assess the value of supplementing heavily T2-weighted, high resolution MR-imaging for detailed anatomic assessment in paediatric lower urogenital tract (UGT) malformations. PATIENTS/METHODS: Sixteen patients (6 male and 10 female, median age=1.8 years, range=0-9 years) with suspected malformations of the lower UGT who were retrospectively identified from the PACS underwent a clinically indicated standard MR-urography study. In order to facilitate a better anatomic assessment of questioned specific lower UGT structures, an additional three-dimensional Constructive Interference in Steady State-sequence (3D-CISS) had been acquired in these patients. The final diagnosis was established by all imaging results and surgical or laprascopic findings. The findings from the CISS-sequence were compared to the results from standard MR-urography for complementary anatomic information and conspicuity. RESULTS: Diagnostic 3D-CISS image quality was achieved in all patients. The 3D-CISS confirmed an ectopic ureteral insertion in six patients and reliably excluded ectopic insertion in 10 patients, whereas conventional MR-urography showed an ectopic insertion of the ureter in one case. In six patients with retrovesical complex formations (suspicious for an ectopic cystic renal bud or a cystic genital structure) the 3D-CISS showed increased conspicuity scores for image quality. CONCLUSION: The additional 3D-CISS-sequence increases the diagnostic yield in the pelvis in children with complex malformations of the lower UGT such as ectopic ureteral insertion or suspected cystic renal or genital malformations at only minimal additional time, compared to standard MR-urography.

[Evaluation and management of enuresis. An update]. / Evaluierung und Management der Enuresis. Ein Update.

Enuresis is defined as nocturnal bed wetting for at least 2 nights per month in children older than 5 years. At this age the prevalence of enuresis is about 15-20%. More than 50% of these children show day time symptoms, such as frequency, urgency and incontinence (non-monosymptomatic enuresis). The other children are asymptomatic during day time and wet the bed during the night time (monosymptomatic enuresis). The main pathogenetic factors are nycturia, detrusor overactivity and reduced arousability. Psychological and psychiatric aspects, genetics and obstipation play an additional role in the etiology. Basic diagnostic investigations are mandatory before treatment. Clinical history, physical examination, sonography of the urinary tract, urinalysis and bladder diary are prerequisites before any therapeutic steps are taken. The cornerstones of primary enuresis therapy are general lifestyle advice, pharmacotherapy and alarm devices. Therapy-resistant children deserve further evaluation and a multidisciplinary therapy approach. After careful evaluation specific therapy is efficient in approximately 80% of patients.

[Correction of hypospadias by the Snodgrass method. Indications and results]. / Hypospadiekorrektur nach Snodgrass. Indikationen und Ergebnisse.

Tubularisation of the urethral plate with a medial incision was popularized by Snodgrass in the late 1990s. Since then this procedure has emerged throughout the world as the method of choice for correction of primary hypospadias. The procedure is applied as the technique of choice for primary correction of hypospadias, regardless of the level of the hypospadic meatus and the width of the original urethral plate, and is also used in various situations for secondary hypospadias surgery.. The complication rate is about 5-10 % in primary cases and between 10% and 20% in revision surgery for hypospadias repair.

[Pelvic kidney in childhood. Specific features, concomitant pathologies and useful diagnostic investigations]. / Kindliche Beckenniere. Spezifika, Begleitpathologien und sinnvolle Diagnostik.

In a retrospective analysis we studied the case histories of 31 children who had been seen in our department for investigation of pelvic ectopic kidney between January 1994 and June 2005. The evaluation of each involved the medical history, ultrasound examination, VCUG, and DMSA scan or MAG3 diuresis renogram. Of the 31 children, 21 (67.7%) had initially been referred to our department for further investigation and clarification because renal agenesis was suspected. In the remaining 10 (32.3%) children the pelvic kidney was an incidental finding observed during investigation of various other conditions. Overall, 7 (22.6%) of the 31 were symptomatic (recurrent urinary tract infections, abdominal pain, hypertension, hydronephrosis), while 77.4% (24/31) were completely free of symptoms at the time of follow-up. Ultrasound revealed that the ectopic kidney was on the left in 64.5% (20/31) of these cases. Nuclear scans performed both at the time of the initial diagnosis and at follow-up were available for 11 of the 31 children and showed a mild improvement of the partial function of the pelvic kidney, from a mean of 25.6% to a mean of 34.6%. In conclusion, whenever renal agenesis is suspected on ultrasonographic examination, the investigator should first consider renal ectopia; ultrasound examination with the bladder full is the definitive diagnostic procedure. For asymptomatic cases we recommend regular ultrasound monitoring of the kidney -- at first every 6 months and later once a year. In cases with complex anatomy MRI is a suitable method for further diagnostic work-up.

[Uterus duplex with hematometrocolpos and ipsilateral agenesis of the kidney]. / Uterus duplex mit Hämatometrokolpos und ipsilateraler Nierenagenesie.

BACKGROUND: Malformations of the mullerian-duct-system occur with an incidence of about 0.001-0.005% of the population, and they are frequently associated with unilateral agenesis of the kidney. CASE: A 12-year-old girl presented to our emergency department with cyclic abdominal pain which increased with each of her menses. Ultrasound investigation showed a uterus duplex with obstructed hemivagina and hematometrocolpos as well as an ipsilateral absence of the kidney. Additionally, a cystic expansion in the small pelvis was detected which required further investigations (MRT and MR-angiography) to establish the diagnosis of a hematosalpinx. Excision of the vaginal septum resulted in drainage of the hemato-metrocolpos and the hematosalpinx. CONCLUSION: Unilateral hematometrocolpos should be considered as an important differential diagnosis in female adolescents with relapsing lower abdominal pain, even if normal menstruation occurs.

Imaging of the neonatal CNS.

Imaging of the central nervous system is one of the major tasks of Paediatric Radiology, particularly in newborns, who present with a variety of conditions that need more or less urgent imaging. Imaging is usually performed primarily by bedside US, in rare cases supplemented by a skull or spine radiograph. For more detailed information and preoperatively, MRI has become the neuroimaging tool. Thus, CT today is only used for acute trauma assessment, for assessment of potential cerebral calcifications or when MRI is not available. In cases with vascular anomalies or unsuccessful punctures, image guided interventions (embolisation) or image guidance for access (lumbar puncture, puncture of skull collections ...) may become necessary. This article tries to give a brief overview on the common disease entities, their typical imaging features in the major modalities applied and the implications of imaging potential for indication and choice of imaging method. In general, acute assessment may become everywhere and major features of important diseases should be recognised not to miss conditions which need urgent treatment or referral to a dedicated paediatric unit. Many other conditions will only be seen at centres with a dedicated neonatal care unit and dedicated paediatric radiologist who then also will be able to provide proper imaging with adapted protocols and methods for these partially severely sick babies. As these specific features and adapted capabilities as well as dedicated training and clinical experience are necessary for providing best results and proper handling in neonates, many neonatal conditions will not be imaged at a peripheral site, but primarily should be referred to a paediatric (radiology) centre.