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Background: Numerous studies have provided evidence for subtle deviations in brain morphology in children with psychiatric disorders, but much less is known about the onset and developmental trajectory of these deviations early in life. We sought to determine whether variances in cerebral ventricular size in fetuses and newborns are associated with temperamental difficulties in infants., Methods: Within a population-based cohort study, we measured the size of the lateral ventricle of the fetus' brain twice during pregnancy. We used 3-dimensional cranial ultrasound to measure the cerebral ventricular volume of infants at age 6 weeks. We then related the size of the cerebral ventricular system to temperamental dimensions at age 3 months using the Mother and Baby Scales, and at age 6 months using the Infant Behavior Questionnaire for a total of 1028 infants., Results: The size of the lateral ventricle of the fetuses in midpregnancy was not related to temperamental difficulties in infants; however, smaller lateral ventricles in late pregnancy were associated with higher activity levels at the age of 6 months. Infants with smaller ventricular volumes at age 6 weeks experienced higher activity levels, more anger or irritability and poorer orienting later in infancy. Children with the lowest ventricular volumes scored on average 0.15 (95% confidence interval 0.06-0.23, p = 0.001) points higher (23%) on activity levels than children with the highest ventricular volumes., Conclusion: Variations in ventricular size before and shortly after birth are associated with temperamental difficulties. Some of the morphologic differences between children with and without psychiatric disorders may develop very early in life.

Introduction: Incontinentia pigmenti (IP) is a rare X-linked dominant neuroectodermal multisystem disorder characterized by skin lesions following Blaschko lines. In almost all patients the skin is involved and in 30-50% the central nervous system (CNS) is. Vascular occlusive phenomena probably play a role in CNS involvement. Whether these vascular changes are based on macro- or microvascular disease in the neonatal presentation is not fully understood., Patients and Methods: We describe two patients with IP with neonatal seizures related to cerebral infarction. In comparison, we reviewed reports of ischaemic cerebrovascular injury in neonatal IP., Results: No descriptions of documented large artery occlusion in neonatal IP was found in the literature. One of our patients showed striatal arteriopathy, never described before in IP. Extensive injury in one of our cases was heterogeneous, mixing healthy with diseased areas within large arterial fields., Conclusions: We postulate that neonatal cerebral infarction in IP is a macrovascular disorder of medium sized or small arteries. The pattern of arterial involvement might follow hypothetical brain Blaschko lines. The extent of cerebral involvement probably results from genetic mosaicism in which Lyonisation leads to endothelial apoptosis, similar to the process in the skin.

Background and Purpose: Hyperintensities on T2-weighted images are seen in the brains of most patients with neurofibromatosis type I (NF-1), but the origin of these unidentified bright objects (UBOs) remains obscure. In the current study, we examined the diffusion characteristics of brain tissue in children with NF-1 to test the hypothesis that a microstructural abnormality is present in NF-1., Materials and Methods: Diffusion tensor imaging (DTI) was performed in 50 children with NF-1 and 8 controls. Circular regions of interest were manually placed in 7 standardized locations in both hemispheres, including UBO sites. Apparent diffusion coefficients (ADC), fractional anisotropy (FA), and axial anisotropy (A(m)) were used to differentiate quantitatively between healthy and disordered brain matter. Differences in eigenvalues (lambda(1), lambda(2), lambda(3)) were determined to examine parenchymal integrity., Results: We found higher ADC values for UBOs than for normal-appearing sites (P < .01) and higher ADC values for normal-appearing sites than for controls (P < .04 in 5 of 7 regions). In most regions, we found no differences in FA or A(m). Eigenvalues lambda(2) and lambda(3) were higher at UBO sites than in normal-appearing sites (P < .04)., Conclusion: With ADC, it was possible to differentiate quantitatively between normal- and abnormal-appearing brain matter in NF-1 and also between normal-appearing brain matter in NF-1 and healthy brain matter in controls, indicating subtle pathologic damage disrupting the tissue microstructure in the NF-1 brain. Higher diffusivity for lambda(1), lambda(2), and lambda(3) indicates that this disturbance of microstructure is caused by accumulation of fluid or vacuolation.

Background: Isolated synostosis of the frontosphenoidal suture is very rare and difficult to diagnose. Little has been reported on the clinical presentation and fetal development of this suture., Objective: To understand the development of the frontosphenoidal suture and the outcome of its synostosis., Materials and Methods: We studied the normal fetal development of the frontosphenoidal suture in dry human skulls and the clinical features of four patients with isolated synostosis of the frontosphenoidal suture., Results: The frontosphenoidal suture develops relatively late during the second trimester of pregnancy, which explains the mild phenotype when there is synostosis. This rare craniosynostosis results in a deformity that causes recession of the lateral part of the frontal bone and supraorbital rim, with minimal facial asymmetry. Three-dimensional CT is the best examination to confirm the diagnosis., Conclusion: Isolated frontosphenoidal synostosis should be considered in patients with unilateral flattening of the forehead at birth that does not improve within the first few months of life.

Background: Malformations of cortical development (MCDs) are a major source of handicap. Much progress in understanding the genetic causes has been made recently. The number of affected children in whom a molecularly confirmed diagnosis can be made is unclear., Objective: To evaluate the etiology of MCDs in children and the effect of a combined radiological, clinical, and syndrome classification., Design: A case series of 113 children with a radiological diagnosis of MCD from January 1, 1992, to January 1, 2006., Setting: The Erasmus Medical Center-Sophia Children's Hospital, a secondary and tertiary referral center., Patients: Patients with MCD underwent a complete radiological, clinical, and neurological assessment and testing for known genes involved in the pathogenesis of MCD as appropriate for their phenotype., Results: We established an etiological diagnosis in 45 of 113 cases (40%). For 21 patients (19%), this included molecular and/or genetic confirmation (Miller-Dieker syndrome; LIS1, DCX, FLNA, EIF2AK3, or KIAA1279 mutations; or an inborn error of metabolism). In 17 (15%), a syndrome with an unknown genetic defect was diagnosed. In 7 patients (6%), we found evidence of a gestational insult. Of the remaining 68 patients, 34 probably have a yet-unknown genetic disorder based on the presence of multiple congenital anomalies (15 patients), a family history with multiple affected persons (12 patients), or consanguineous parents (7 patients)., Conclusions: In our cohort, combining diagnostic molecular testing with clinical, radiological, and genetic classification; syndrome identification; and family study provided a diagnosis in 40% of the cases of MCD. This contributes to the possibility of prenatal diagnosis and improved patient treatment and disease management.

The cerebral ventricular system is a marker of brain development and a predictor of neurodevelopmental outcome. In premature or dysmature neonates, neuroanatomical structures including the ventricular system appear to be altered. The present study aims to provide information on the association between foetal growth and neonatal cerebral ventricular size in the normal population. Within the Generation R Study, a population-based cohort study, we used three-dimensional cranial ultrasound to determine lateral ventricular volume in 778 term infants aged 4-12 weeks. Foetal growth characteristics were repeatedly measured in early, mid- and late pregnancy and analysed in relation to ventricular volume divided by head circumference. Results revealed positive associations between foetal head circumference in late pregnancy and log-transformed ventricular volume (beta=0.077, 95% confidence interval (0.017; 0.136), equivalent to a 7.7% increase in ventricular volume per standard deviation of head circumference). Similarly, in a per week-longer gestational duration, ventricular volume in infancy was 6.0% larger. Multilevel modelling demonstrated that reduced growth of foetal head circumference and biparietal diameter during pregnancy were associated with decreased ventricular volume in infancy. In conclusion, foetal maturation is positively associated to cerebral ventricular size in term infants. Larger ventricular size in term infants needs to be distinguished from ventricular enlargement due to intraventricular haemorrhage or white matter damage in premature or dysmature infants. Moreover, the naturally occurring enlargement of ventricles during infancy should be considered in interpreting reports on increased ventricular volumes in several neuropsychiatric disorders.

Background: Ultrasonography (US) as a diagnostic tool in the work-up of boys with nonpalpable testes (NPT) is still controversial., Objective: To evaluate the relation between US and operative findings in boys with NPT., Materials and Methods: During a 7-year period we saw 135 boys with 152 NPT. All were examined by the referring physician or a paediatric surgeon, underwent US examination, and were then re-examined afterwards by a specialist. Finally, all boys were surgically explored for testicular position., Results: US located 103 NPT (68%), 16 within the abdomen and 87 in the inguinal canal. With knowledge of the US result, 37 testes were palpable on re-examination. The sensitivity of US was 97% for inguinal and 48% for abdominal viable testes. Of the 49 testes (32%) missed by US, 16 were viable in either the abdominal (n=14) or the inguinal (n=2) position., Conclusion: All boys with presumed NPT should be referred to a specialist. US is useful to determine localization of NPT, which facilitates planning the surgical procedure. An inguinal exploration is called for when US identifies the testis in the inguinal canal. Because the sensitivity of US for viable abdominal testes is only 48%, we now always perform laparoscopic exploration when US is negative.

The authors describe a case of split notochord syndrome with a neuroenteric fistula in a newborn presenting with meningitis. Associated anomalies included agenesis of the corpus callosum, short colon, malrotation, epispadias, and an abnormally high bifurcation of the abdominal aorta and inferior vena cava. The embryological mechanisms and etiologic theories are discussed in short.

Two families are presented with a child suffering from microcephaly with a simplified gyral pattern of the brain (SGP) and early onset insulin dependent diabetes mellitus (IDDM). The first patient was diagnosed postmortally with Wolcott-Rallison syndrome, after her younger brother developed IDDM, and a homozygous mutation in the eukaryotic translation initiation factor 2-alpha kinase 3 was found. The younger brother did not undergo magnetic resonance imaging (MRI). The patient from the second family has no EIF2AK3 mutation. SGP is considered to arise from decreased neuronal proliferation or increased apoptosis at an early stage of embryonal development, but insight into the pathways involved is minimal. EIF2AK3 is involved in translation initiation. It has been proposed that loss of function mutations reduce the ability of the cell to respond to endoplasmic reticulum stress, resulting in apoptosis of pancreatic Langerhans cells. Our findings suggest that in some cases, early onset IDDM and SGP can arise from common mechanisms leading to increased apoptosis.

Purpose: Triphalangeal thumb is characterized as a congenital difference of the thumb with an extra phalanx. Additional thumb length is attributed mostly to the extra phalanx. The influence of the epiphyseal plate positions on growth in congenital hand anomalies is unclear. The purpose of this article was to compare the length of the first metacarpal in triphalangeal thumbs with the length of the same bone in normal thumbs and to investigate the influence of the often aberrant metacarpal epiphyseal plates on the length of the triphalangeal thumb metacarpal during growth., Methods: The positions of the epiphyseal plate and the relative length of the first metacarpal were examined retrospectively in 37 patients with triphalangeal thumb. Ratios of the measurements were calculated (metacarpal II/metacarpal I) and compared with a normal population. Subjects were divided into 3 groups based on the position of the epiphyseal plate (double, proximal, distal)., Results: The distally placed growth plate was the most common variety, present in 22 of patients, followed by the proximal position in 14, and double epiphyseal plates in 6. All ratios of patients with triphalangeal thumb were significantly smaller than those of a normal population, indicating a longer first metacarpal in this condition. First metacarpals in triphalangeal thumb with double epiphyses grew disproportionately more than those of a normal population, whereas those with distal epiphyses grew disproportionately less than normal. First metacarpals with proximal epiphyses grew at the same rate as normal first metacarpals., Conclusions: In this study population the most common growth plate location was distal whereas the most common location in the normal population is proximal. The different positions of the epiphyseal plates correlate with growth differences in patients with triphalangeal thumb.

Background: Porencephaly (cystic cavities of the brain) is caused by perinatal vascular accidents from various causes. Several familial cases have been described and autosomal dominant inheritance linked to chromosome 13q has been suggested. COL4A1 is an essential component in basal membrane stability. Mouse mutants bearing an in-frame deletion of exon 40 of Col4a1 either die from haemorrhage in the perinatal period or have porencephaly in survivors. A report of inherited mutations in COL4A1 in two families has shown that familial porencephaly may have the same cause in humans., Objective: To describe three novel COL4A1 mutations., Results: The three mutations occurred in three unrelated Dutch families. There were two missense mutations of glycine residues predicted to result in abnormal collagen IV assembly, and one mutation predicted to abolish the traditional COL4A1 start codon. The last mutation was also present in an asymptomatic obligate carrier with white matter abnormalities on brain magnetic resonance imaging., Conclusions: This observation confirms COL4A1 as a major locus for genetic predisposition to perinatal cerebral haemorrhage and porencephaly and suggests variable expression of COL4A1 mutations.

A 1.5-year-old boy presented with progressive ataxia and meningeal irritation after a period of general malaise and fever. He was eventually admitted to a paediatric intensive care unit for respiratory insufficiency. A diagnosis of acute disseminated encephalomyelitis (ADEM) with pontine involvement was made. The patient was mechanically ventilated and treated with immunoglobulins and corticosteroids, after which he recovered almost completely. ADEM is characterised by rapidly progressive demyelination of the central nervous system. The exact incidence and aetiology are unknown. The disorder is considered to be an autoimmune reaction, and current treatment is aimed at the suppression of this reaction. Despite the dramatic clinical and radiological presentation of ADEM, the prognosis is favourable in most cases.

Background: In recent years interest in bone densitometry in children has increased., Objective: To evaluate the clinical application of digital X-ray radiogrammetry (DXR) and compare the results with those of dual-energy X-ray absorptiometry (DXA)., Materials and Methods: A total of 41 children with acute lymphoblastic leukaemia (ALL) and 26 children with growth hormone deficiency (GHD) were included in this longitudinal study. Radiographs of the left hand were obtained and used for DXR. DXA of the total body and of the lumbar spine was performed., Results: In both study populations significant correlations between DXR and DXA were found, and, with the exception of the correlation between DXR bone mineral density (DXR-BMD) and bone mineral apparent density in the GHD population, all correlations had a P-value of <0.001. During treatment a change in DXR-BMD was found in children with GHD., Conclusions: Our study showed that DXR in a paediatric population shows a strong correlation with DXA of the lumbar spine and total body and that it is able to detect a change in BMD during treatment.

Intraspinal location of central PNET (cPNET) is very rare. We present a case, critically review all publications of primary intraspinal cPNET occurrence and discuss tendencies in clinical presentation. In several previous attempts to summarise, authors often confused cPNET with peripheral PNET (pPNET). cPNET and pPNET are different entities with different immunohistochemical profiles and genetic backgrounds. Clinically, they are both aggressive tumours, but exhibit different characteristics in their local manifestation and metastatic spread. Survival rates are quite similar provided that treatment is applied according to the established protocols. Protocols in cPNET treatment differ from those for pPNET as regards the order of the treatment sub-modalities, specific chemotherapeutic regimen and intensity, radiation dose and its extent and consequently, the side effects. Therefore, failure to distinguish cPNET from pPNET leads to clinical guidance and treatment proposals based on false assumptions, which might effect outcomes. Often, distinguishing between cPNET and pPNET is easy, because they occur in different location. In the case of intraspinal tumour location, however, the differentiation is crucial because both primary cPNET and pPNET can occur intraspinally, even though this is rare. Nowadays, demonstrating the expression of MIC2 glycoprotein by immunocytochemical staining (CD99) showing the specific EWS-FLI1 chimeric gene presence in pPNET, offers an easy way of making a differential diagnosis between cPNET and pPNET.

Malonyl-CoA decarboxylase (MCD) deficiency is an extremely rare inborn error of metabolism that presents with metabolic acidosis, hypoglycemia, and/or cardiomyopathy. Patients also show neurological signs and symptoms that have been infrequently reported. We describe a girl with MCD deficiency, whose brain MRI shows white matter abnormalities and additionally diffuse pachygyria and periventricular heterotopia, consistent with a malformation of cortical development. MLYCD-gene sequence analysis shows normal genomic sequence but no messenger product, suggesting an abnormality of transcription regulation. Our patient has strikingly low appetite, which is interesting in the light of the proposed role of malonyl-CoA in the regulation of feeding control, but this remains to be confirmed in other patients. Considering the incomplete understanding of the role of metabolic pathways in brain development, patients with MCD deficiency should be evaluated with brain MRI and unexplained malformations of cortical development should be reason for metabolic screening.

Background: Reducing the dose for each CT scan is important for children with cystic fibrosis (CF)., Objective: To determine whether the number of CT images and therefore the dose per CT scan could be reduced without any significant loss of information in children with CF., Materials and Methods: A cohort of children with CF was followed with biennial surveillance CT scans, obtained in inspiration after a voluntary breath-hold as 1-mm thick images at 10-mm intervals from lung apex to base. A random set of 20 baseline CT scans and 10 follow-up CT scans were blinded. Sets of every image (10-mm intervals), every second image (20-mm intervals), every third image (30-mm intervals) and a selection of three and five images were scored randomly using a published CT scoring system by one experienced observer., Results: The 20 subjects were 10 years of age with a range of 3.7-17.6 years at baseline. Fewer CT images resulted in a significantly lower (less abnormal) CT score and the number of patients positive for abnormalities decreased subsequently. At intervals greater than 20 mm no significant change in CT score over 2 years could be detected, while the CT scores at 10-mm (P=0.02) and 20-mm (P=0.02) intervals worsened significantly., Conclusions: A reduction in the number of inspiratory CT images by increasing the interval between images to greater than 10 mm is not a valid option for radiation dose reduction in children with CF.

Background and Purpose: Meningoencephalitis can severely damage the developing brain. Preterms are more prone for nosocomial infections with pathogens other than Group B streptococci and Escherichia coli. In this report we focus on the deleterious clinical course and imaging characteristics of proven Bacillus cereus meningoencephalitis., Methods: We collected 3 cases of proven Bacillus cereus meningoencephalitis. In the medical records we focused on prenatal, perinatal, and postnatal risk factors. Imaging data of several brain ultrasounds, MR images, and diffusion-weighted images were reevaluated., Results: The ultrasound and MR images show a typical pattern of mainly hemorrhagic and early cavitating, selective white matter destruction., Conclusion: Knowledge of this paradigm of acquired brain injury may help to better understand the natural course of these severe neonatal infections.

Introduction: No evidence based treatment is available for atelectasis. We aimed to evaluate the clinical and radiologic changes in pediatric patients who received DNase for persistent atelectasis that could not be attributed to cardiovascular causes, and who were unresponsive to treatment with inhaled bronchodilators and physiotherapy., Methods: All non-cystic fibrosis pediatric patients who received nebulised or endotracheally instilled DNase for atelectasis between 1998 and 2002, with and without mechanical ventilation, were analysed in a retrospective descriptive study. The endpoints were the blood pCO2, the heart rate, the respiratory rate, the FiO2 and the chest X-ray scores before and after treatment., Results: In 25 of 30 patients (median [range] age, 1.6 [0.1-11] years) who met inclusion criteria, paired data of at least three endpoints were available. All clinical parameters improved significantly within 2 hours (P < 0.01), except for the heart rate (P = 0.06). Chest X-ray scores improved significantly within 24 hours after DNase treatment (P < 0.001). Individual improvement was observed in 17 patients and no clinical change was observed in five patients. Temporary deterioration (n = 3) was associated with increased airway obstruction and desaturations. No other complications were observed., Conclusion: After treatment with DNase for atelectasis of presumably infectious origin in non-cystic fibrosis pediatric patients, rapid clinical improvement was observed within 2 hours and radiologic improvement was documented within 24 hours in the large majority of children, and increased airway obstruction and ventilation-perfusion mismatch occurred in three children, possibly due to rapid mobilisation of mucus. DNase may be an effective treatment for infectious atelectasis in non-cystic fibrosis pediatric patients.

We describe two children who developed ischemic strokes in the territory of the middle cerebral artery, one 7 days and one 11 days after resection of a cerebellar tumor. In the first child, another infarction occurred in the territory of the contralateral middle cerebral artery 5 days after the first stroke. No specific cause or underlying risk factor other than the surgical procedure was found. The subacute clinical course at stroke onset resembled that of the 'posterior fossa syndrome', suggesting a common underlying mechanism.

We identified, by homozygosity mapping, a novel locus on 10q21.3-q22.1 for Goldberg-Shprintzen syndrome (GOSHS) in a consanguineous Moroccan family. Phenotypic features of GOSHS in this inbred family included microcephaly and mental retardation, which are both central nervous system defects, as well as Hirschsprung disease, an enteric nervous system defect. Furthermore, since bilateral generalized polymicogyria was diagnosed in all patients in this family, this feature might also be considered a key feature of the syndrome. We demonstrate that homozygous nonsense mutations in KIAA1279 at 10q22.1, encoding a protein with two tetratrico peptide repeats, underlie this syndromic form of Hirschsprung disease and generalized polymicrogyria, establishing the importance of KIAA1279 in both enteric and central nervous system development.

Purpose: To retrospectively compare thin-section computed tomographic (CT) scores obtained with five scoring systems for assessment of pulmonary disease in children with cystic fibrosis and to determine additional value of bronchial and arterial dimension measurements., Materials and Methods: Scores obtained with five thin-section CT scoring systems were compared. A score of 0 indicated the absence of abnormalities; a higher score meant that more structural abnormalities were seen. Three observers assigned scores and then reassigned scores after intervals varying from 1-2 weeks to 1-2 months at review of thin-section CT scans obtained in 25 children with cystic fibrosis. Interobserver and intraobserver reliability was calculated with intraclass correlation coefficients. Quantitative measurements of bronchial and arterial dimensions were obtained. Thin-section CT scores were correlated (Spearman correlation) with bronchial and arterial dimensions and with results of pulmonary function tests (PFTs), such as forced expiratory volume in 1 second (FEV(1))., Results: Scores with all five scoring systems were reproducible, with intraclass correlation coefficients of 0.74 and higher (P <.05), and showed significant correlations with FEV(1) (R = -0.73 to -0.69, P <.01). Ratio of bronchial diameter to accompanying pulmonary arterial diameter was correlated with thin-section CT scores but not with FEV(1). Ratio of bronchial wall thickness to accompanying pulmonary arterial diameter was not correlated with thin-section CT scores or PFT results., Conclusion: Thin-section CT scores were reproducible and were correlated with PFT results. Measurements of bronchial dimensions were not significantly related to scores or PFT results.

We have evaluated the applicability of a new Digital X-ray Radiogrammetry (DXR) system in a Dutch Caucasian pediatric population. For this study we enrolled 535 healthy participants who all signed an informed consent form. In addition, 20 children suffering from inflammatory bowel disease (IBD) and juvenile chronic arthritis (JCA) were enrolled. Radiographs of the left hand were obtained from all participants. From the healthy population a subset of children with a history of forearm fractures were separately analyzed. Measurements consisted of DXR (X-posure; Pronosco-Sectra, Linköping, Sweden). Five hundred thirty-five subjects were enrolled in the study. Twenty-two subjects (4.3%) were discontinued (age 3-10 years), all because of a nonrecognizable radiograph by the DXR system. The short-term coefficient of variation of DXR in this population was 0.59%. Significant differences in DXR-BMD between boys and girls for the ages of 11, 12, 16, 17, and 18 years were found. There were also significant differences in DXR-BMD between the sequential Tanner stages. For 88 subjects repeat radiographs were available (mean interval 1.8 years). In all cases an increase in DXR-BMD was seen. Girls with IBD, JCA, or a history of forearm fractures and boys with IBD showed a significantly lower DXR-BMD compared with healthy controls. We show that DXR is an applicable technique in children. Also, in a small subpopulation it is possible to discriminate children with a high risk of low BMD.

The aim of this study was to demonstrate the ultrasonographic features of prenatal torsion of the testis at presentation and during follow-up, with histological correlation post-orchidectomy. Between January 1985 and December 1999, 13 neonates with antenatal torsion of the testis were examined postnatally, at presentation and during follow-up, with high-resolution ultrasonography, including colour Doppler ultrasonography. Bilateral testis volume was evaluated [lengthxwidthxdepthx(pi/6)]. Ultrasonographic findings were correlated with histological findings (n=8) and findings at surgery. Moreover, in 1 patient the affected testis was postoperatively examined with ultrasonography in vitro. These findings were correlated with preoperative ultrasonography and corresponding histological slices. All patients (n=13) presented with a painless congenital scrotal mass. On the affected side no flow was found with colour Doppler ultrasonography. Testis volume on the affected and normal side showed mean values of 2.1 and 0.5 cc, respectively. On ultrasonography all patients showed scrotal swelling and a heterogeneous testis with hypoechoic central areas (necrosis). The tunica albuginea was thickened in all patients, with focal (n=2) or rim-like (n=11) hyperechoic reflections (calcifications) at the transitional zone between testis and tunica albuginea. In 9 patients follow-up ultrasonography showed progressive testis atrophy on the affected side. In 10 patients a contralateral hydrocele was found. Prenatal torsion shows a characteristic ultrasonographic pattern. In newborns with a scrotal mass, these ultrasonographic findings should suggest this diagnosis and delay in immediate surgery and/or oncological work-up may be appropriate.

Arterial stroke in a neonate caused by carotid artery dissection is rare. We report two cases, one with dissection at the level of the skull base, one just distal to the carotid bulb. Non-invasive techniques like MR angiography and sonography demonstrated the dissection accurately. MR imaging, especially the diffusion-weighted images, showed the extension and site of the cerebral infarction. In one case dissection could be suspected following vacuum and forceps extraction. In the other no obvious birth trauma was reported. In conclusion, in a neonate with clinical signs suggestive of cerebral infarction, dissection of the carotid artery should be considered.

For effective clinical management of cystic fibrosis (CF) lung disease it is important to closely monitor the start and progression of lung damage. The aim of this study was to investigate the ability of high-resolution computed tomography (HRCT) scoring systems and pulmonary function tests (PFT) to detect changes in lung disease. CF children (n=48) had two HRCT scans in combination with two PFT 2 yrs apart. Their scans were scored using five scoring systems (Castile, Brody, Helbich, Santamaria and Bhalla). "Sensitivity" was defined as the ability to detect disease progression. In this group of children, HRCT scores worsened. PFT remained unchanged or improved. Of the HRCT parameters, mucous plugging and the severity, extent and peripheral extension of bronchiectasis worsened significantly. Relationships between changes in HRCT scores and PFT were weak. Substantial structural lung damage was evident in some children who had normal lung function. These data show that high-resolution computed tomography is more sensitive than pulmonary function tests in the detection of early and progressive lung disease, and suggest that high-resolution computed tomography may be useful in the follow up of cystic fibrosis children and as an outcome measure in studies that aim to reduce lung damage.

Background/purpose: The aim of this study was to add to the experience of slide tracheoplasty in infants with congenital tracheal stenosis (CTS), to review the recent literature on this subject, and to evaluate the diagnostic workup in infants with CTS., Methods: A retrospective review of 3 infants with CTS treated with slide tracheoplasty was conducted at our institution. They all underwent bronchoscopy, tracheobronchography, and echocardiography. Therapy consisted of slide tracheoplasty and simultaneous correction of associated vascular malformations., Results: A pulmonary artery sling was missed initially on esophagography in 2 patients. Stridor became worse in 2 patients after tracheobronchography. After surgical therapy, 2 patients survived and were discharged 12 days after surgery. Both are without symptoms at follow-up of 12 and 20 months. One patient had inoperable restenosis and died 27 days after the operation., Conclusions: Esophagography is not a reliable tool to depict associated vascular anomalies for patients with CTS. According to the literature, computer tomography has become more reliable to depict the tracheobronchial tree and is useful to elucidate associated vascular anomalies as well. Compared with other surgical techniques for infants with CTS reported in the literature, slide tracheoplasty has fewer postoperative complications and comparable survival rates.

Familial porencephaly is a rare disorder causing motor impairment, hemiplegia, mental retardation and epilepsy in variable degrees. Two families with porencephaly and apparently dominant inheritance are reported. Brain MRI findings are reviewed and described in seven affected individuals. Most patients also show white matter abnormalities in the cerebral hemisphere, also contralateral to the cystic lesion. In the first family an obligate carrier was identified who did not have a cystic lesion but clear abnormalities of the white matter. Although a predisposition for thrombophilia has previously been reported, we did not observe any genetic, environmental or epigenetic predisposition for the porencephaly. The lesions are most compatible with a deep venous thrombosis/ischemic event occurring in a late stage of pregnancy, not necessarily aggravated by perinatal asphyxia.

Anatomical studies suggest that normal lungs grow by rapid alveolar addition until about 2 yrs of age followed by a gradual increase in alveolar dimensions. The aim of this study was to examine the hypothesis that normal lung growth can be monitored by computed tomography (CT). Therefore, the gas volume per gram of lung tissue was estimated from measurements of lung density obtained from CT scans performed on children throughout the growth period. CT scans were performed on 17 males and 18 females, ranging in age from 15 days-17.6 yrs. CT-measured lung weight was correlated with predicted post mortem values and CT measured gas volume with predicted values of functional residual capacity. The median value for lung expansion was 1.86 mL x g(-1) at 15 days, decreased to 0.79 mL x g(-1) by 2 yrs and then increased steadily to 5.07 mL x g(-1) at 17 yrs. Computed tomography scans can be used to estimate lung weight, gas volume and expansion of normal lungs during the growth period. The increase in the lung expansion after the age of 2 yrs suggests progressive alveolar expansion with increasing lung volume.

We report the CT and MRI findings of congenital bilateral plexiform neurofibromas of the cavernous sinuses in a 2-month-old girl. Contrast-enhanced CT showed enhancement of masses in both cavernous sinuses and enlargement of both superior orbital fissures. On MRI the masses were isointense with muscle on T1-weighted images, hypointense on T2-weighted images and showed strong homogeneous enhancement on contrast-enhanced T1-weighted images. A dural tail sign was observed. The diagnosis was proven by biopsy.

Background: Several longitudinal studies have shown contradictory results regarding the change in bone status in children with acute lymphoblastic leukaemia (ALL) using dual-energy X-ray absorptiometry as the bone assessment technique., Objective: To determine whether a more recently developed bone assessment technique which does not use radiation, tibial ultrasonometry, can be used for the detection of short-term changes., Patients and Methods: From January 1997 to February 2001, 37 patients (25 boys, 12 girls, mean age 9.0 years, range 3.0-16.8 years) were included in a longitudinal study to assess changes in bone status induced by the disease itself and/or treatment. Of these 37 patients, 35 had a measurement at the start of therapy (t0), 26 at 6 months (t6), 24 at 12 months (t12), 11 at 24 months (t24) and 9 at 36 months (t36). For assessment of bone mass, the tibial ultrasound (US) device SoundScan Compact was used, which measures the speed of sound (SOS) along the cortex of the tibia over a fixed length of 5 cm at the mid-tibial point. RESULTS. The SOS standard deviation (SD) scores were significantly lower at t6, t12, t24 and t36 than at baseline (t0). The biggest change was found between t0 and t6. During follow-up, no significant correlation was found between changes from baseline of height SD scores and SOS SD scores, indicating that tibial ultrasonometry was not measuring growth. After ending therapy (t36), no further growth retardation was found., Conclusions: Short-term changes of SOS SD scores in children with ALL can be detected by tibial ultrasonometry. Tibial ultrasonometry measures a change in bone status, not growth.

A large proportion of the variation in bone mass can be explained by genetic factors. We analyzed the G to T substitution in the Sp1 binding site in the first intron of the collagen type Ialpha1 (COLIA1) gene in relation to bone mass. The genotypes GG, GT, and TT were determined in 148 Caucasian children and young adults. We performed dual energy X-ray absorptiometry twice (mean follow-up time 4.4 years), and speed of sound (SOS) was assessed by tibial ultrasonometry at follow-up. Genotype distribution was 104 (70%) GG, 40 (27%) GT and 4 (3%) TT. Carriers of the T-allele had a 0.5 SDS (standard deviation score) decreased bone mineral content (BMC) of total body (P = 0.001), and a 0.4 SDS decreased bone mineral density (BMD) for both lumbar spine (P = 0.04) and total body (P = 0.05). The genotype effect on BMD and BMC decreased after adjustment for height or body mass index. When we calculated apparent BMD, these differences diminished to 0.1 SDS and were no longer significant. T-allele carriers had shorter stature (0.4 SDS; P = 0.04) and smaller bones (0.5 SDS lower width of the lumbar vertebral body; P = 0.01). The T-allele was also associated with lower SOS (P = 0.03), independent of BMD and BMC, and lower lean body mass. Similar associations were found at follow-up. The change in BMD and BMC SDS between the first and second measurement did not differ between the GG and GT&TT group. In conclusion, the COLIA1 polymorphism in children and young adults is associated with several bone characteristics. However, at least a part of the COLIA1 effect on bone mass may be related to differences in frame size.

Acute lymphoblastic leukemia (ALL) in childhood is a serious disease that can affect growth and the attainment of maximal peak bone mass. The latter has recently been recognized as a risk factor for the development of osteoporosis later in life. To determine long-term effects of the disease itself and its treatment, we assessed the bone status of a group of long-term survivors of childhood ALL, all treated with high doses of steroids (dexamethasone) and methotrexate and without cranial irradiation. All 21 subjects enrolled in this cross-sectional study were diagnosed to have non-high-risk precursors acute lymphoblastic leukemia (12 boys and 9 girls, mean age 16.5 yr, range 12.2-25.4 yr). Standard deviation (SD) scores were calculated using a tibial ultrasound device and spinal dual-energy X-ray absorptiometry (DXA) device as bone assessment techniques. SD scores of those two different bone assessment techniques were compared. The mean SOS (speed of sound) SD scores (SDS) of the tibia (mean 0.26, standard deviation [sd] 1.00) were not significantly different from our reference value of 0. There was no significant difference between the SOS SDS in boys and girls. With DXA, no significant difference was seen between the mean BMD SDS and the reference data and no significant difference in BMD between boys and girls was found. The individual mean SDS for bone mineral density (BMD) of lumbar spine are 0.24 (sd 1.02), total body 0.17 (sd 1.00), and apparent BMD (BMAD) 0.07 (sd 1.09). Spearman's correlation between mean SOS SDS and mean BMD of lumbar spine was 0.47, mean SOS SDS and mean BMAD SDS was 0.43, and mean SOS SDS and mean BMD of total body was 0.49. These correlations were significant at the 0.05 level (two tailed). Despite high-dose dexamethasone and methotrexate used for treatment of these children with ALL, no long-term side effects on the bone mineral status of the subjects, measured with DXA or tibial ultrasonometry, could be determined.

We report a case of spinal epidural abscess presenting as abdominal pain. An 7-year-old boy presented with abdominal pain. He was operated on under suspicion of appendicitis. During operation, no abnormalities were found. Postoperatively, the abdominal pain did not subside. Subsequently, the boy developed neurological abnormalities. MRI showed a spinal epidural abscess. A laminectomy was performed and the boy was treated with antibiotics; he recovered well. This case showed that it is important to consider a spinal epidural abscess as a cause of abdominal pain with fever in children.

Objective: The modified Blalock-Taussig shunt is a synthetic shunt between the subclavian and pulmonary artery, frequently used in the treatment of children with pulmonary hypoperfusion caused by congenital heart disease. The development of a perigraft seroma is a known complication of this procedure. We sought to describe the imaging features of a perigraft seroma and to define an optimal diagnostic strategy in patients with a suspected perigraft seroma., Materials and Methods: Between January 1993 and December 1998, 96 children underwent 105 modified Blalock-Taussig shunt procedures. In eight children, 11 cases of perigraft seromas were identified. The mean age of these children at the time of operation was 3 years (range, 6 days to 5 years 8 months). Pre- and postoperative chest radiographs were routinely performed in the children in whom seromas had been found. Additional postoperative radiologic investigations consisted of thoracic sonography (in 11 cases), CT (in eight cases), and MR imaging (in two cases). In all cases of perigraft seroma, the modified Blalock-Taussig shunts were constructed through a posterolateral thoracotomy at the fourth intercostal space., Results: On average, the chest radiographs showed the first signs of the seroma on day 10 after the surgery (range, day 1-day 30). Using thoracic sonography, it was possible to visualize the perigraft seroma and the modified Blalock-Taussig shunt in eight (73%) of 11 cases. CT and MR imaging performed equally well in revealing perigraft seromas., Conclusion: As was found in these critically ill children, sonography has an advantage over CT and MR imaging because of its portability and, therefore, capability for bedside use. We recommend the use of sonography as the initial imaging modality in suspected cases of perigraft seroma development.

Background: In our Paediatric Radiology Department, the Greulich and Pyle technique is used to assess skeletal age. Several authors have raised questions with regard to the applicability of this technique in a contemporary paediatric and adolescent population., Objective: To compare skeletal age and calendar age in a healthy Dutch Caucasian population in order to test the applicability in this specific population., Materials and Methods: For this study we enrolled 278 Dutch Caucasian boys (age range 5.0-19.5 years, mean 12.6 years) and 294 Dutch Caucasian girls (age range 5.2-19.9 years, mean 12.2 years). Radiographs of the left hand were scored according to the Greulich and Pyle atlas by two investigators., Results: Intra-observer coefficient of variation of duplicate assessment of skeletal age for investigator 1 (resident) was 2.4 % and for investigator 2 (radiologist) was 1.5 %. We found no significant systematic differences between the two observers regarding variability and levels of measurement, and the agreement was good. There was a strongly significant correlation between skeletal and calendar age rgirls = 0.974 and rboys = 0.979 (P < 0.001). On average, calendar age preceded skeletal age by a small amount (1.7 months in girls and 3.3 months in boys, both P < 0.001)., Conclusions: The reliability of the Greulich and Pyle atlas in our study corresponds well with previously reported studies. Based on our data, we conclude that the Greulich and Pyle atlas is still applicable in Dutch Caucasian children and adolescents.

In the field of bone densitometry, attention has recently been focused on the pediatric population. Quantitative ultrasound (QUS) as bone assessment technique has many advantages for children in comparison with bone assessment techniques that use ionizing radiation. In this pilot study, we investigated the use of calcaneal and tibial QUS systems in a healthy Caucasian pediatric population. We studied 120 healthy Caucasian Dutch children between ages 7 and 19 yr: 53 boys (mean age of 12.5 yr, range 4.5-18) and 67 girls (mean age of 13.5 yr; range 7.1-19). We recruited children from a large population who previously had participated in a bone assessment study performed at our hospital. Two operators performed calcaneal QUS of the right calcaneus and tibial QUS of the right tibia. The correlation between calcaneal and tibial ultrasound was modest but significant (r = 0.29; p < 0.01). Using the calcaneal device, we found in girls a weak positive correlation between skeletal age and speed of sound (SOS) (r = 0.38), broadband ultrasound attenuation (r = 0.57), and quantitative ultrasound index (r = 0.46), all with a value of p < 0.01. For boys all parameters failed to reach significance. Using the tibial device, we found a good correlation between skeletal age and SOS in girls (r = 0.76) and modest correlation in boys (r = 0.50), both with a value of p < 0.01. This is one of the first studies to present a comparison between two ultrasound techniques in children. At present we feel that, in light of the poor correlation with skeletal age, calcaneal ultrasound has yet to prove its efficacy in children. Tibial ultrasound seems to be a good bone assessment technique in children.

There is a need for a reliable bone assessment technique in children. In this study, we compare an existing technique used in children, radiographic absorptiometry (RA), with a relatively novel technique, quantitative tibial ultrasonometry (QUS). In a prospective cohort study, we enrolled 290 girls (mean age 12.7 years) and 273 boys (mean age 12.4 years). Radiographs of the left hand and the left index finger were taken with an aluminium reference wedge within the field of exposure. Radiographic absorptiometry on the second middle phalanx at the mid-level (BMD50%) and proximal quarter (BMD25%) was performed with interactive software. Tibial QUS was performed using the SoundScan Compact. Multiple regression analysis showed that SOS correlated significantly with BMD25% for both boys (r = 0.65, P < 0.001) and girls (r = 0.59, P < 0.001), taking into account age and gender. The same applied for the correlation between speed of sound (SOS) and BMD50% in boys (r = 0.62, P < 0.001) and girls (r = 0.67, P < 0.001). Cubic regression between calendar age and BMD25% showed the best fit for both boys (r2 = 0.60) and girls (r2 = 0.60). For BMD50% a difference in regression was found between boys and girls. Quadratic regression gave a satisfactory fit for boys (r2 = 0.61 ) whereas for girls, a cubic relation was best (r2 = 0.59). Overall, there was a significant correlation between BMD25% and BMD50% for boys r = 0.89 and for girls r = 0.91 (both P < 0.001). Our data show a significant correlation between two different bone assessment techniques. In addition, these data suggest that both tibial ultrasonometry and RA are useful techniques in children.

Pancreatic agenesis is a rare condition, of which only a limited number of cases have been described. One recent paper reported a homozygous mutation in the pancreatic duodenal homeobox gene 1 (PDX-1) in a child with pancreatic agenesis. We report a 6-year-old boy with pancreatic agenesis, treated medically, without abnormalities in the PDX-1 gene coding sequence and with normal gastroduodenal endocrine cell distribution. Genes other than PDX-1 also appear to be involved in human pancreatic agenesis.

Rationale and Objectives: To understand normal bone development, studies in healthy children and adolescents are important. To assess the applicability of tibial quantitative ultrasound measurements (QUS) in children, we performed a study that compared dual-energy x-ray absorptiometry (DXA) of the lumbar spine and whole body with tibial QUS., Methods: For this study we recruited 146 Dutch children and adolescents, 58 boys (median age, 14.1 years; range, 7.6-23.4 years) and 88 girls (median age, 18.0 years; range, 7.6-23.5 years). Tanner stage, weight, and height were assessed for all participants. Bone mineral density (BMD; g x cm(-2)) of the whole body and lumbar spine (L2-L4) and bone mineral apparent density (BMAD) of the lumbar spine (g x cm(-3)) were assessed by using the Lunar DPXL. For tibial QUS, the Soundscan compact system was used., Results: Both lumbar as well as whole-body BMD showed a strong, significant correlation with tibial QUS in boys and girls: rtotal body boys = 0.81, rtotal body girls = 0.77, rlumbar spine boys = 0.79, and rlumbar spine girls = 0.72. Lumbar spine BMAD also showed significant correlations with tibial QUS: rboys= 0.63 and rgirls = 0.63 (for all correlations, P < 0.001)., Conclusions: Our study showing strong, significant correlations between DXA and tibial QUS measurements suggests that tibial QUS is a technique that may be applicable in children and adolescents.

Background: Prolonged 3-dimensional echocardiography (3DE) acquisition time currently limits its routine use for calculating left ventricular volume (LVV) and ejection fraction (EF). Our goal was to reduce the acquisition time by defining the largest rotational acquisition interval that still allows 3DE reconstruction for accurate and reproducible LVV and EF calculation., Methods: Twenty-one subjects underwent magnetic resonance imaging and precordial 3DE with 2 degrees acquisition intervals. Images were processed to result in data sets containing images at 2 degrees, 4 degrees, 8 degrees, 16 degrees, 32 degrees, and 64 degrees intervals by excluding images in between. With use of the paraplane feature, 8 equidistant short-axis slices were generated from each data set. The suitability of these short-axis slices for manual endocardial tracing was scored visually by 4 independent experienced observers. The LVV and EF were calculated by using Simpson's rule from 3DE data sets with 2 degrees, 8 degrees, and 16 degrees intervals, and the results were compared with values obtained from magnetic resonance imaging. The probability of 3DE to detect LVV and EF differences was calculated., Results: All patients were in sinus rhythm with a mean heart rate of 72 bpm (SD + or - 12). The LV short-axis images obtained with 16 degrees rotational scanning intervals allowed LV endocardial tracing in all subjects. Good correlation, close limits of agreement, and nonsignificant differences were found between values of LVV and EF calculated with 3DE at 2 degrees, 8 degrees, and 16 degrees rotational intervals and those obtained with magnetic resonance imaging. At steps of 16 degrees, 3DE had excellent correlation (r = 98, 99, and 99), close limits of agreement (+ or - 38, + or - 28.6, and + or - 4.8), and nonsignificant differences (P =.5,.8, and.2) with values obtained from magnetic resonance imaging for calculating end-diastolic LVV, end-systolic LVV, and EF, respectively. Three-dimensional echocardiography with use of 16 degrees rotational intervals could detect 15-mL differences in end-diastolic volume with a probability of 95%, 11-mL differences in end-systolic volume with a probability of 92%, and 0.02 differences in EF with a probability of 95%., Conclusions: The 3DE data sets reconstructed with images selected at 16 degrees intervals from data sets obtained at 2 degrees precordial rotational acquisition intervals allowed the generation of LV short-axis images with adequate quality for endocardial border tracing. Therefore precordial acquisition at 16 degrees intervals would be sufficient for the reconstruction of 3DE data sets for LV function measurement. This would reduce the acquisition time while maintaining enough accuracy for clinical decision making and would thus make 3DE more practical as a routine method.

Bone densitometry in children is a relatively new topic of interest within the field of osteoporosis. Bone densitometry techniques using an X-ray source have the disadvantage of radiation exposure. Also on some systems, motion artifacts are caused by long scan times. Tibial quantitative ultrasonometry (QUS) is ideally suited for children as it is radiation free and the interactive measurement provides real-time quality control. In this prospective study, we present data from 596 healthy children-309 girls, mean age 12.9 years (range 6.1-19.9), and 287 boys, mean age 12.3 years (range 6.1-19.6) from Rotterdam, The Netherlands. For all subjects, a short questionnaire regarding overall health was completed. To assess skeletal age, an X-ray of the left hand was taken and tibial QUS of the right tibia was performed using the SoundScan Compact. A statistically significant correlation was found between age and speed of sound (SOS)-r(2)(boys) = 0.52 and r(2)(girls) = 0.63 (both P < 0.001) and between skeletal age and SOS-r(2)(boys) = 0.56 and r(2)(girls) = 0. 63 (both P < 0.001). In boys, significant increase of mean SOS is seen between Tanner stages II and III and between IV and V. In girls there is a significant increase of mean SOS among all Tanner stages, except stages II and III. This is the first study to present normative tibial QUS data for Caucasian children and adolescents. In this study, normative data relative to skeletal age are also provided, facilitating the implementation of this technique in children with growth disorders showing dissociation between calendar and skeletal age.

Objective: We evaluated the Doppler sonography of small feeding arteries to the femoral head in children., Subjects and Methods: In a prospective study of 224 hips in 112 patients (mean age, 5 years 11 months), the anterior ascending cervical arteries of the hip were identified with color Doppler sonography. Subsequently, we measured the resistive index (RI) with pulsed Doppler sonography., Results: In 61% (137/224) of hips, a Doppler signal could be obtained. In asymptomatic hips (n = 64), the mean RI was 0.58. In symptomatic hips, the definitive diagnoses and mean values of RI included transient synovitis (n = 31) and 0.92, Perthes' disease (n = 9) and 0.67, and miscellaneous (n = 5) and 0.68. In 28 symptomatic hips, no definite diagnosis could be determined and the complaints spontaneously disappeared during follow-up (mean RI, 0.57). We found no statistically significant difference in the RI of symptomatic versus asymptomatic hips, except in patients with transient synovitis (p < 0.001). In 11 hips with transient synovitis that were reexamined after 4-6 weeks, the RI returned to normal (0.57). The RI in symptomatic hips showed a positive correlation with the amount of effusion (r = 0.69, p < 0.001). In symptomatic and asymptomatic hips, we found no correlation with age (p = 0.9 and 0.1, respectively)., Conclusion: The deep capsular vessels of the hip joint can be evaluated on Doppler sonography in more than 60% of hips. Also, the RI is age independent and correlates with the amount of effusion.

The availability of improved therapies for children with diseases affecting bone growth and/or metabolism has caused increased interest in bone mineral density (BMD) assessment. The purpose of this study was to determine normal values for phalangeal radiographic absorptiometry (RA) in a Caucasian pediatric population. Five hundred and seventy-two healthy Caucasian children and adolescents (aged 5-19 years) were enrolled in this study. For RA one posteroanterior exposure of the left hand and one lateral exposure of the left index finger were taken. All films were analyzed, yielding BMD (mg Al/mm3) values for two phalangeal sites: one at the proximal quarter of the phalangeal length (BMD25%) and the second at the midpoint of the phalangeal length (BMD50%). Also skeletal age (SA) was assessed, as data normalized for SA can be used in populations which show a dissociation between SA and calendar age. We found that the BMD25% was significantly higher in girls than in boys for the SA group 11-14 years. The BMD50% was significantly higher in girls than in boys for the SA group 11-15 years. Our data show that BMD25% remains fairly constant until the SA of 12.0 years in boys and 10.1 years in girls; after these skeletal ages BMD shows a sharp increase. The same applies to BMD50%, which remains fairly constant until the SA of 12.4 years in boys and 10.7 years in girls. In this paper we present normative data for RA in a pediatric population. These data normalized for skeletal age could be implemented in a clinical setting.

In the past, children with many brain malformations were classified as having static encephalopathies (cerebral palsy), often attributed to perinatal or prenatal distress. Understanding of the frequency and clinical manifestations of brain malformations, however, has increased dramatically in the past 10 to 15 years. During this time, it has become apparent that many static encephalopathies in children have a brain malformation as their substrate. Most of the increase in our knowledge can be attributed to advances in neuroimaging and in molecular biology. In general, radiologic analysis of the brain allows similar malformations to be classified together. Subsequent genetic analysis of the affected children often reveals the affected gene, leading to identification of the gene product and, ideally, an ultimate understanding of the molecular mechanism of malformation. Currently, many genes involved in the complicated process of neuronal proliferation, migration, and organization are being identified. Knowledge of these genes and a better radiologic classification system enable the referring physician to give better care, more sophisticated genetic counseling, and a more precise prognosis for the child. To illustrate this mechanism of classification, three groups of malformations are discussed, in which a combination of neuroimaging analysis and molecular biologic analysis have led to a new understanding of the malformation syndromes.

Objective: To evaluate the significance of thickening of the wall of the renal collecting system by US., Materials and Methods: Wall thickening of the renal collecting system was seen during US in 62 collecting systems of 51 patients over a period of 2 years. The medical and radiological records of these patients were reviewed with special attention to the definitive diagnosis and other clinical and radiological parameters. Moreover, a control group consisting of 48 renal collecting systems was examined to establish normal values for the thickness of the wall of the collecting system., Results: Of the 62 collecting systems (mean wall thickness 1.6 mm, range 0.8-3.1 mm), vesicoureteric reflux (VUR) was present in 18 cases, urinary tract infection (UTI) in 11, and both VUR and UTI in 9 cases. In 10 cases, intermittent dilatation was present caused by primary obstructive megaureter (n = 2), pelvi-ureteric junction stenosis (n = 4), high-pressure bladder (n = 3), or of unknown cause (n = 1). In 11 cases, transient dilatation had been present in the recent past (usually prenatally detected hydronephrosis), but had disappeared at the time of the US examination. In 3 patients, no definite cause for the wall thickening could be established. In the control group, wall thickness ranged from 0.1 to 0.8 mm., Conclusions: The upper limit for wall thickness of the normal collecting system in children is 0.8 mm. Thickening of the wall of more than 0.8 mm should be considered as pathological and is caused by urinary tract infection, intermittent dilatation (e. g., VUR), and dilatation in the recent past.

The objective of this study was to determine the degree of muscle wasting of various components of the quadriceps muscle in children with a painful hip. Between January 1994 and September 1997, 327 consecutive children with a unilateral painful hip and/or limping were evaluated prospectively with ultrasonography. Quadriceps thickness was measured on both sides. Moreover, muscle thickness was measured in 59 control subjects. The patients were divided into eight groups; transient synovitis (n = 134), Perthes' disease (n = 35), slipped capital femoral epiphysis (n = 5), osteomyelitis (n = 4), aspecific synovitis (n = 5), rheumatoid arthritis (n = 3) and miscellaneous (n = 16). In 125 patients, no sonographic and radiological abnormalities were found and during follow-up the symptoms disappeared ('no pathology' group). Ipsilateral muscle wasting was present in all patient groups, whereas the control subjects showed no significant difference in muscle thickness between legs. The degree of muscle wasting was compared between transient synovitis, the 'no pathology' group, Perthes' disease and control subjects. For both quadriceps and vastus intermedius muscles, there was a significant difference between these groups, except between control subjects and the 'no pathology' group. For the rectus femoris muscle, there was a significant difference between these groups, except between transient synovitis and 'no pathology'. Muscle wasting showed a positive correlation with duration of symptoms and pre-existing muscle mass. In conclusion, different diseases show different degrees of muscle wasting, and there are different patterns of muscle wasting of various components of the quadriceps femoris muscle.