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Background. Focal nodular hyperplasia (FNH) is an unusual hepatic tumour in children and should be distinguished from other hepatic lesions. Objective. To describe the imaging characteristics of FNH in children. Materials and methods. We examined five patients (three boys and two girls, mean age 9.4 years) with pathologically confirmed FNH. The diagnosis was obtained by tumour resection (n = 4) and percutaneous needle biopsy (n = 1). One patient with multiple FNHs showed recurrent lesions after tumour resection. All patients were studied with US (including colour and power Doppler US [n = 3]) and CT. Dynamic enhanced CT scans were available in three patients. MRI (n = 2) or coeliac angiography (n = 1) was performed in three patients. Results. Seven of eight FNH lesions in five patients were demonstrated by imaging. The average size of the lesions was 6.5 cm. Six lesions detected on US showed variable echogenicity with a central hyperechoic scar (n = 2). On Doppler examination, central or peripheral hypervascular areas were seen (n = 3). Six lesions detected on contrast-enhanced CT showed high attenuation (n = 4) or iso-attenuation (n = 2). On early phase scans, all the lesions (n = 3) showed high attenuation. Irregular linear or ovoid central scars were detected in two patients on CT. MR demonstrated three lesions in two patients, one of which had not been detected by US or CT. A central low signal intensity scar (n = 1) was seen on T2-weighted MRI. Coeliac angiography performed in one patient showed a hypervascular mass with homogeneous staining. Conclusion. FNH in children shows a wide spectrum of imaging findings on various radiological examinations and the typical central scar was not always seen on imaging studies. Dynamic enhanced CT obtained in the early phase and colour Doppler studies may be helpful in the diagnosis of FNH by allowing characterisation of tumour vascularity. FNH should be included in the differential diagnosis of liver mass in children.

To differentiate at ultrasonography (US) between the choledochal cyst associated with biliary atresia (CCBA) and that in the absence of biliary atresia (CC) in neonates and young infants.Preoperative US findings in 28 neonates and infants younger than 4 months in whom choledochal cyst was subsequently surgically confirmed were retrospectively analyzed. There was no statistically significant difference in age between the CCBA group (n = 19) and the CC group (n = 9). US findings in both groups were compared, with focus on the size of the cyst in the hepatic portal, dilatation of the intrahepatic bile ducts, and the size and morphology of the gallbladder.At US, the width and length of the cysts in the hepatic portal in the CC group were significantly larger than those in the CCBA group (P.001). Dilatation of the intrahepatic bile ducts, seen in only one patient (5%) of the CCBA group, was observed in all patients (100%) of the CC group. The gallbladder was normal or distended in all patients of the CC group, while it was atretic or irregularly elongated in 17 patients (89%) of the CCBA group.US can be helpful in the preoperative differential diagnosis of choledochal cysts in neonates and infants. Cysts are larger, intrahepatic ducts are dilated, and gallbladders are not atretic in patients with CC as compared with those in patients with CCBA.

The purpose of this study was to correlate CT findings of congenital cystic adenomatoid malformation (CCAM) of the lung with pathologic findings.CT scans of CCAM from 21 consecutive patients were analyzed retrospectively by two chest radiologists who achieved consensus. Pathologic findings were assessed by an experienced pulmonary pathologist. Preoperative CT findings were correlated with pathologic findings.Areas with small cysts (2 cm in diameter) were seen on CT scans in 19 (90%) of 21 patients, whereas areas with a large cyst (2 cm in diameter) were observed in 18 patients (86%). Areas of consolidation (n = 9; 43%) with heterogeneous attenuation on enhanced scans and areas of low attenuation (lower than normal lung) around cystic lesions (n = 6; 29%) were also seen on CT scans. The diameter of the largest cyst seen on CT scans in each patient ranged from 1.0 to 8.0 cm (median, 4.5 cm). Cysts that CT showed to be filled with air, fluid, or both correlated completely with the pathologic findings. Areas of consolidation corresponded histologically to areas of glandular or bronchiolar structures with or without areas of endogenous lipoid or organizing pneumonia or mucus plugs. Areas of low attenuation corresponded to areas of microcysts blended with normal lung parenchyma.CT scans show the variable internal characteristics of CCAM and can suggest the underlying pathology of such lesions.

Background: Preterm birth is known to be associated with risks of impaired nephrogenesis. Objectives: To determine the normal range of renal sizes at birth in preterm infants as well as their short-term postnatal renal growth, to assess the correlation between initial renal size and growth parameters at birth and to compare the initial and serial renal sizes between appropriate-for-gestational-age (AGA) and small-for-gestational-age (SGA) preterm infants. Methods: Initial ultrasonography (US) was prospectively performed in 125 preterm infants within the first 72 h of life and every 2 weeks thereafter until a postmenstrual age (PMA) of 37 weeks was reached. Correlation between renal size and growth parameters was investigated. Renal lengths of AGA and SGA preterm infants were compared with those of age-matched fetuses described in the literature. Results: The renal sizes at birth in preterm infants are presented. Multiple regression analysis showed the strongest correlation between initial renal size and birth weight (p < 0.0001). Initial renal lengths of AGA infants were not significantly different from those of age-matched fetuses at ≥30 weeks' gestational age (GA), whereas those of SGA infants were significantly smaller at ≥28 weeks' GA. Serial renal lengths of SGA infants were significantly smaller than fetal renal lengths at ≥30 weeks' GA. Conclusion: With US, the normal range of initial renal sizes of AGA preterm infants was defined according to GA. In contrast to AGA infants, SGA infants showed smaller initial renal sizes and no significant catch-up growth until a PMA of 37 weeks.

The aim of this study was to investigate the prevalence, severity, and relationships between xerostomia and its related symptoms in individuals who attended hospital for general health examinations. Participants included 883 men and 618 women aged between 30 and 60 years. History of symptoms during the previous 6 months, current symptoms, and severity of current symptoms were evaluated using a questionnaire that included questions about xerostomia, burning mouth, taste disturbance, and oral malodor. The prevalence of xerostomia and its related symptoms was 60.2%; the prevalence of oral malodor was 52.3%, xerostomia 33.0%, burning mouth 13.6%, and taste disturbance 12.5%. Men in their 30s and women in their 60s showed significantly higher prevalence and greater severity of xerostomia, burning mouth, and taste disturbance compared with their counterparts. The prevalence of xerostomia, burning mouth, and taste disturbance, and the severity of xerostomia increased significantly with age in women. The prevalence and severity of these four symptoms were significantly related and the association was the highest between burning mouth and taste disturbance. In conclusion, xerostomia and its related symptoms were highly prevalent at all ages. The prevalence and severity of these symptoms were closely related.

Purpose To evaluate the incremental value of a combination of magnetic resonance cholangiopancreatography (MRCP) and ultrasonography (US), compared to US alone, for diagnosing biliary atresia (BA) in neonates and young infants with cholestasis. Materials and Methods The institutional review board approved this retrospective study. The US and MRCP studies were both performed on 64 neonates and young infants with BA (n = 41) or without BA (non-BA) (n = 23). Two observers reviewed independently the US alone set and the combined US and MRCP set, and graded them using a five-point scale. Diagnostic performance was compared using pairwise comparison of the receiver operating characteristics (ROC) curve. The sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value were assessed. Results The diagnostic performance (the area under the ROC curve [Az]) for diagnosing BA improved significantly after additional review of MRCP images; Az improved from 0.688 to 0.901 (P = .015) for observer 1 and from 0.676 to 0.901 (P = .011) for observer 2. The accuracy of MRCP combined with US (observer 1, 95% [61/64]; observer 2 92% [59/64]) and PPV (observer 1, 95% [40/42]; observer 2 91% [40/44]) were significantly higher than those of US alone for both observers (accuracy: observer 1, 73% [47/64], P = 0.003; observer 2, 72% [46/64], P = 0.004; PPV: observer 1, 76% [35/46], P = 0.016; observer 2, 76% [34/45], P = 0.013). Interobserver agreement of confidence levels was good for US alone (ĸ = 0.658, P < .001) and was excellent for the combined set of US and MRCP (ĸ = 0.929, P < .001). Conclusion Better diagnostic performance was achieved with the combination of US and MRCP than with US alone for the evaluation of BA in neonates and young infants with cholestasis.

Esophageal candidiasis is commonly seen in immunocompromised patients; however, candida esophagitis induced stricture is a very rare complication. We report the first case of esophageal stricture secondary to candidiasis in a glycogen storage disease (GSD) 1b child. The patient was diagnosed with GSD type 1b by liver biopsy. No mutation was found in the G6PC gene, but SLC37A4 gene sequencing revealed a compound heterozygous mutation (p.R28H and p.W107X, which was a novel mutation). The patient's absolute neutrophil count was continuously under 1,000/µL when he was over 6 years of age. He was admitted frequently for recurrent fever and infection, and frequently received intravenous antibiotics, antifungal agents. He complained of persistent dysphagia beginning at age 7 years. Esophageal stricture and multiple whitish patches were observed by endoscopy and endoscopic biopsy revealed numerous fungal hyphae consistent with candida esophagitis. He received esophageal balloon dilatation four times, and his symptoms improved.

Neonatal hemochromatosis (NH) is a severe neonatal liver injury that is confirmed by extra-hepatic iron accumulation. Although a recent study described treating NH with exchange transfusions and intravenous immunoglobulin, liver transplantation should be considered for patients with severe liver failure that does not respond to other medical treatment. Herein, we report the case of a two-month-old female infant who presented with persistent ascites and hyperbilirubinemia. Her laboratory findings demonstrated severe coagulopathy, high indirect and direct bilirubin levels, and high ferritin levels. Abdominal magnetic resonance imaging presented low signal intensity in the liver on T2-weighted images, suggesting iron deposition. The infant was diagnosed with NH as a result of the clinical findings and after congenital infection and metabolic diseases were excluded. The infant was successfully treated with a living-donor liver transplantation. Living related liver transplantation should be considered as a treatment option for NH in infants.

Desmoplastic cerebral astrocytoma of infancy (DCAI) presents as a large supratentorial mass consisting of a central cystic component and an enhancing solid component associated with peripheral dural attachment. We report the unusual MR findings of a DCAI that differed from previously reported cases in terms of the presence of calcification, which is not considered a feature of this tumor, and the absence of an enhancing peripheral dural component.

Six cases of undifferentiated embryonal sarcoma (UES) were reviewed to determine their characteristic features on ultrasonography (US) (n = 5) and computed tomography (CT) (n = 6). US demonstrated a single large, echogenic mass with some anechoic spaces. Contrast-enhanced CT scan revealed a well-demarcated low-attenuation mass with hyperdense septations of variable shape and thickness. Discrepancy of internal architecture on US and CT was one of the important characteristics of UES. CT numbers were 25-47 HU in low-attenuation areas. Enhancing peripheral rim was found in four cases and some solid portions at the periphery or adjacent to the septa were found in all cases. Two patients who had follow-up US and CT without treatment showed enhancing solid portions, changing to hypodense as the tumor grew. When compared with the pathologic findings, US showed a more accurate representation of internal architecture than did CT. Familiarity with these US and CT findings of UES of the liver will be helpful in the differential diagnosis of primary hepatic tumors in childhood.

Clinical features, images, complications, treatments, and prognosis of 10 children with congenital portosystemic shunt (CPSS) were reviewed. Nine children were diagnosed with intrahepatic shunts while one presented with extrahepatic shunt. CPSS was detected by prenatal ultrasonography in four infants. Three infants presented with galactosemia without an enzyme deficiency. Two children presented with mental retardation and attention deficit hyperactivity disorder. Pulmonary hypertension developed in two patients. Spontaneous closure occurred in four infants with intrahepatic shunts including patent ductus venosus. The shunts were closed using transcatheter embolizations in four patients with intrahepatic shunts. Conclusion: Intrahepatic shunts may close spontaneously. Transcatheter embolization is effective for the treatment of symptomatic intrahepatic shunts.

Sinus pericranii is a rare venous anomaly, which shows abnormal communication between the intracranial and extracranial venous systems. Sonograms of sinus pericranii in 4 children were retrospectively reviewed to evaluate the following imaging findings: the overall sonographic appearance, change in size and shape, Doppler flow pattern, and associated anomalies. All 4 patients had irregularly shaped anechoic lesions with lobulating and bulging contours. They all showed intracranial and extracranial venous communication through a calvarial defect. Two patients had changes in the sizes and shapes of the lesions, and 2 patients had bidirectional turbulent flow on Doppler images. Two patients had isolated sinus pericranii, and the other 2 were associated with Crouzon syndrome. By identifying a venous scalp mass with intracranial and extracranial venous communication and changes in its size, shape, and venous flow pattern, radiologists will be able to make a definitive diagnosis of sinus pericranii by using gray scale and Doppler sonography.

The authors retrospectively reviewed their experience with balloon dilation of esophageal strictures in infants and children to determine the prevalence of esophageal perforation during this procedure.Balloon dilation was performed in 32 patients with esophageal stricture due to either congenital or postoperative stenosis. The total number of procedures was 141; each patient underwent one to 12 procedures.Four cases of esophageal perforation occurred during balloon dilation and were detected immediately after the procedure. Perforation in three of these patients was treated nonoperatively with parenteral fluid and antibiotics, and one patient was treated surgically with resection and creation of an anastomosis. The clinical course after treatment was favorable in all cases.Although esophageal perforation during balloon dilation of benign strictures has been reported as a rare complication, four perforations were observed in 32 patients. Esophageal perforation can occur in infants and children more frequently than previously reported.

The purpose of this study was to develop an experimental model of pulmonary metastases using VX-2 tumor, and to describe sequential radiologic and pathologic findings with special attention to the interstitial changes around the metastatic nodules. Through ear veins of 25 rabbits, VX-2 tumor cell suspension was injected with 0.8-mm scalp needles. Chest radiographs were taken every other day after tumor injection. The rabbits were sacrificed at scheduled times from 3 to 30 days after tumor injection. The inflated and fixed lungs were examined with visual inspection, low-kV radiography, high resolution CT (HRCT), microradiography of the sliced lung and with histopathologic studies. Hematogeneous pulmonary metastases occurred in 24 of 25 rabbits. In addition to the metastatic nodules, perinodular and peribronchovascular infiltrations were seen on low-kV radiography, HRCT, microradiography and histologic studies.

Congenital obstruction of the pulmonary vein without anomalous drainage can cause long-standing pulmonary congestion and pulmonary arterial hypertension, and it may include stenosis of individual pulmonary veins and pulmonary vein atresia. We reviewed seven cases of pulmonary vein obstruction, five of which were accompanied by other cardiac anomalies. Right pulmonary veins were involved in all seven cases; one case was bilateral. Pulmonary veins were occluded totally in five and partially in three lungs. Diagnostic pulmonary catheterization and angiography were performed. Chest radiographs of total occlusion cases showed decreased lung volume, features of pulmonary edema, interstitial lesions, and pleural changes, which were quite specific, whereas pulmonary venous dilatation was the dominant finding in partial obstruction cases. Pulmonary perfusion scan (n = 3) showed total perfusion defects in the cases with total occlusion of pulmonary veins. Magnetic resonance (MR) imaging (n = 2) demonstrated totally occluded pulmonary veins at the venoatrial junction in two lungs and membranous focal obstruction in one lung. Two children underwent pneumonectomy and had the diagnosis histologically confirmed. Although catheterization and angiography are essential for the diagnosis of pulmonary vein obstruction, MR imaging is a useful adjunct.

Ozonolyses of the vinyl ethers 1a-f in methanol afforded almost exclusively the corresponding α-methoxy hydroperoxides 4, suggesting the preferred formation of the carbonyl oxides 2. In aprotic solvents including methyl formate, the predominant modes of decay of the carbonyl oxides 2 were cyclodimerization, reduction, and rearrangement, yet no ozonide formation. By contrast, ozonolyses of 1a-f on polyethylene gave the α-methoxy-substituted ozonides 14 in fair yields. Ozonolyses of 1a-f in the presence of added carbonyl compounds 6 in methylene chloride or ether yielded the corresponding cross ozonides. Judged from the ozonide yields, the reactivities of the carbonyl compounds follow the sequence: (ClCH 2 ) 2 C=O>ClCH 2 COCH 3 >(CH 3 ) 2 C=O and 2-CF 3 C 6 H 4 CHO>PhCHO

Ozonolyses of the 1-substituted methyl vinyl ethers 5, 8, and 16, bearing bulky substituents, and of the 2-substituted and 2,2-disubstituted methyl vinyl ethers , respectively, afforded the corresponding ozonides which have been isolated and characterized. In most cases, dry ozonolysis on polyethylene was advantageous over ozonolysis in solution. Ozonolysis of the 1,2,2-trisubstituted vinyl ether 34 gave no ozonide under either conditions

We report a case of thymic hyperplasia accompanied by pericardial lipomatosis and right facial hemihypertrophy in an 8-year-old boy. On imaging studies, the hyperplastic thymus had prominent curvilinear and nodular fatty areas simulating a fat-containing anterior mediastinal mass, which is an unusual finding in children. To our knowledge, this is the first report on a child with a combination of thymic hyperplasia, pericardial lipomatosis, and right facial hemihypertrophy. The radiologic findings are presented with a brief discussion.

Objective The purpose of this study was to examine the clinical applicability of Doppler sonography by evaluating Doppler sonographic findings in an experimental rabbit model of necrotizing enterocolitis (NEC). Methods Necrotizing enterocolitis was experimentally induced using a combination of endotoxin, hypoxia, and cold stress in 23 rabbits. Doppler sonography was performed to obtain the Doppler spectrum of the superior mesenteric artery. From the flow profile, the peak systolic velocity (PSV) and resistive index (RI) were calculated at 5 time sessions: initial and 1 to 2, 3 to 4, 5 to 6, and 20 to 24 hours. Animals were divided into 2 groups based on pathologic NEC scores (NEC-positive [NEC+] group versus NEC-negative [NEC-] group). Differences between the groups with regard to RI and PSV values were evaluated for each time session. Results Comparison of RI and PSV values between the NEC+ and NEC- groups revealed a significant increase in the PSV in the NEC+ group during the 1- to 2-hour session (P = .0199). Comparison of RI and PSV differences revealed a significant increase in RI and PSV differences in the NEC+ group during the 1- to 2-hour session (P = .0095 and .0013, respectively). In the other time sessions, there was no difference between the groups. Conclusions The NEC+ group showed a significant increase in the PSV and RI during the 1- to 2-hour period.

Objective: To determine whether there is a correlation between liver MR find-ings and the clinical manifestations and severity of liver dysfunction in patientswith Wilson’s disease.Materials and Methods: Two radiologists retrospectively evaluated MRimages of the liver in 50 patients with Wilson’s disease. The Institutional ReviewBoard approved this retrospective study and informed consent was waived. MRimages were evaluated with a focus on hepatic contour abnormalities and thepresence of intrahepatic nodules. By using Fisher’s exact test, MR findings werecompared with clinical presentations (neurological and non-neurological) andhepatic dysfunction, which was categorized by the Child-Pugh classification sys-tem (A, B and C). Follow-up MR images were available for 17 patients.Results: Contour abnormalities of the liver and intrahepatic nodules wereobserved in 31 patients (62%) and 25 patients (50%), respectively. Each MR find-ing showed a statistically significant difference ( p < 0.05) among the three groupsof Child-Pugh classifications (A, n = 36; B, n = 5; C, n = 9), except forsplenomegaly ( p = 0.243). The mean age of the patients with positive MR find-ings was higher than that of patients with negative MR findings. For patients withChild-Pugh class A (n = 36) with neurological presentation, intrahepatic nodules,surface nodularity, and gallbladder fossa widening were more common.Intrahepatic nodules were improved (n = 8, 47%), stationary (n = 5, 29%), oraggravated (n = 4, 24%) on follow-up MR images.Conclusion: MR imaging demonstrates the contour abnormalities andparenchymal nodules of the liver in more than half of the patients with Wilson’sdisease, which correlates with the severity of hepatic dysfunction and clinicalmanifestations. ilson’s disease or progressive hepatolenticular degeneration is an autoso-mal recessive disorder of copper metabolism (1). The gene that causesWilson’s disease, located at chromosome 13 band q14.3, is known tocode for a copper-transporting P-type ATPase (2-4). A mutation of the gene associ-ated with Wilson’s disease results in deficient biliary excretion of copper, leading toexcessive copper accumulation in many tissues. Copper accumulation occurs mainly inthe liver, but also in the brain, cornea, and kidney (1-5). The principal clinical manifes-tations of Wilson’s disease are either hepatic or neurological disease (6, 7). Ultrasound (US), CT, and MR findings of the liver in Wilson’s disease usually reflectnonspecific hepatic injury including fatty infiltration, acute hepatitis, chronic activehepatitis, and cirrhosis (8-12). In advanced Wilson’s disease, nodular infiltrationssuggesting the presence of copper-containing nodules and contour abnormalities consis-Jung-Eun Cheon, MD

Ozonolyses of the 1-substituted methyl vinyl ethers 5, 8, and 16, bearing bulky substituents, and of the 2-substituted and 2,2-disubstituted methyl vinyl ethers , respectively, afforded the corresponding ozonides which have been isolated and characterized. In most cases, dry ozonolysis on polyethylene was advantageous over ozonolysis in solution. Ozonolysis of the 1,2,2-trisubstituted vinyl ether 34 gave no ozonide under either conditions

To identify the anal sphincter complex and levator ani muscle at transperineal ultrasonography (US) with the infracoccygeal approach.Infracoccygeal US was performed with a 7-MHz linear-array transducer in 40 healthy neonates. The babies were placed in the supine position, and both legs were drawn up to the chest. The buttocks were accordingly lifted up. The approach site was just inferior to the coccyx and posterior to the anus. Scanning was performed to obtain transverse images of the anorectal area. The thickness of the anal sphincter complex and the puborectalis muscle were measured.Infracoccygeal US revealed the internal anal sphincter (IAS), the external anal sphincter (EAS), and the puborectalis muscle in all babies. The IAS and EAS were depicted as inner and outer hypoechoic ringlike structures, respectively. A round, hyperechoic space (intersphincteral space) was present between the hypoechoic IAS and EAS. The puborectalis muscle was identified as a U-shaped hypoechoic structure. The bulbocavernosus and ischiocavernous muscles were also identified. Mean thicknesses were as follows: IAS, 1.3 mm +/- 0.3 (SD) (range, 0.8-1.9 mm); EAS, 1.6 mm +/- 0.3 (range, 1.2-2.3 mm); and puborectalis muscle, 1.1 mm +/- 0.3 (range, 0.6-1.9 mm).Infracoccygeal transperineal US is an excellent diagnostic modality for demonstrating the anal sphincter complex and levator ani muscle in neonates.

Congenital abnormalities of the portal venous system are rare. There are few radiological descriptions of intrahepatic portosystemic venous shunt detected in the perinatal period. We report a congenital portosystemic shunt that was detected by US and treated with coil embolisation in the neonatal period.

OBJECTIVE. The purpose of this study was to evaluate retrospectively the CT and sonographic features in nine children with pathologically proven inflammatory myofibroblastic tumors of the abdomen.CONCLUSION. Although inflammatory myofibroblastic tumors occur in various sites and the imaging characteristics are variable, tumors showed different imaging patterns that were dependent on the site at which the tumor had originated.

Congenital esophageal stenosis (CES) can be associated with esophageal atresia/tracheoesophageal fistula (EA/TEF). Because there are a variety of degrees of obstruction and symptoms of CES, it is frequently difficult to make a pre- and post-operative diagnosis of the distal CES associated with EA/TEF.To evaluate the clinical and radiologic features of congenital esophageal stenosis associated with esophageal atresia/tracheoesophageal fistula.We retrospectively reviewed postoperative esophagograms and medical records of 187 children (107 boys, 80 girls) who had primary repair of EA/TEF from 1992 to 2009 at our institution. We evaluated the incidence of CES, clinical findings, radiologic features and management of CES in these children.CES was diagnosed in 22 of 187 EA/TEF children (12%); one child had double CES lesions, for a total of 23 lesions. Ten of those 22 children (45%) had presented with significant symptoms of esophageal obstruction. The diagnosis of CES was delayed in 10 children (45%) until 1-10 years of age. On esophagogram, CES (n = 23) was located in the distal esophagus (n = 20, 87%) or mid-esophagus (n = 3, 13%). The degree of stenosis was severe (n = 6, 26%), moderate (n = 10, 43%), or mild (n = 7, 30%). Eight children, including two with unsuccessful esophageal balloon dilatation of CES, were treated surgically. Histologic examination revealed tracheobronchial remnant (n = 7) or fibromuscular hyperplasia (n = 1). One child with surgically treated CES developed achalasia at the age of 3 years 9 months.Esophagography after EA/TEF repair should be performed with a high index of suspicion for the presence of distal CES, because the diagnosis and adequate management of CES can often be delayed.

The purpose of our study was to determine whether CT provides additional information for children with a suspected residual foreign body in the airway after bronchoscopy.We reviewed the CT findings and medical records of nine patients (five girls and four boys; mean age, 17.9 months) who underwent CT between March 1999 and February 2007 for the evaluation of a clinically suspected residual foreign body in the airway after bronchoscopy. We evaluated the location and pattern of bronchial obstruction and associated parenchymal abnormalities on CT. CT findings were compared with a second bronchoscopy in five patients. The remaining four patients were followed clinically. Association between CT findings and results on second bronchoscopy was evaluated with Fisher's exact test.CT after bronchoscopy (n = 9) showed bronchial obstruction in eight patients with focal complete (n = 3), diffuse (n = 3), or combined type (n = 2) bronchial obstruction. These obstructions were not seen at chest radiography. CT revealed unilateral or lobar emphysema (n = 6), atelectasis (n = 6), and consolidation (n = 1). The remaining one patient showed no abnormality on CT. A second bronchoscopy (n = 5) confirmed the focal complete bronchial obstruction at CT (n = 3) as retained foreign body fragments (n = 2) or mucus plug (n = 1) and the combined type at CT (n = 2) as retained foreign body fragments, granulation tissue, and edema of the bronchus (n = 1) or retained foreign body fragments, granulation tissue, and mucus plug (n = 1). There was a significant association between CT findings of type of bronchial obstruction and intrabronchial obstructive lesion on the second bronchoscopy (p = 0.036).CT after bronchoscopy can provide additional information regarding the presence and pattern of bronchial obstruction in children with a suspected residual foreign body.

With the increasing application of intra-arterial chemotherapy (IAC), new side-effects are encountered. We describe two children with proximal femoral osteosarcoma who developed focal myositis of the abdominal wall musculature after IAC. In both cases, myositis presented as abdominal pain and mimicked acute abdomen. US demonstrated asymmetrical thickening of abdominal-wall musculature in the right lower abdomen. This diagnosis should be considered when evaluating the patient with unexplained abdominal pain and a history of IAC.

Central skull base tumours are rare in children. To characterize the imaging features of central skull base lymphoma in children to aid its diagnosis. The authors reviewed the CT findings (available in three patients) and MR findings (available in four patients) in four patients (three boys, one girl; age 2–12 years) with pathologically proven lymphoma (two with Burkitt lymphoma, two with B-cell lymphoma) involving the central skull base. Tumour location and extent, MRI signal intensities, noncontrast CT attenuation, patterns of enhancement, and changes in adjacent structures were evaluated. All four tumours involved the sphenoid bone. In three patients, the tumour extended to the ethmoid sinus and both cavernous sinuses. All lesions were isointense solid masses on T2-weighted images and showed avid enhancement, except for one lesion with a focal necrosis. All tumours were associated with adjacent dural thickening. Non-contrast CT showed highly attenuating masses and permeative bone destruction in the central skull base. Lymphoma involving the central skull base in children is visualized as an isointense mass on T2-weighted MRI with marked contrast enhancement and adjacent dural thickening, and as a highly attenuating mass on noncontrast CT with permeative or erosive bone destruction patterns.

Ozonolyses of the vinyl ethers 1a-f in methanol afforded almost exclusively the corresponding α-methoxy hydroperoxides 4, suggesting the preferred formation of the carbonyl oxides 2. In aprotic solvents including methyl formate, the predominant modes of decay of the carbonyl oxides 2 were cyclodimerization, reduction, and rearrangement, yet no ozonide formation. By contrast, ozonolyses of 1a-f on polyethylene gave the α-methoxy-substituted ozonides 14 in fair yields. Ozonolyses of 1a-f in the presence of added carbonyl compounds 6 in methylene chloride or ether yielded the corresponding cross ozonides. Judged from the ozonide yields, the reactivities of the carbonyl compounds follow the sequence: (ClCH 2 ) 2 C=O>ClCH 2 COCH 3 >(CH 3 ) 2 C=O and 2-CF 3 C 6 H 4 CHO>PhCHO

Patients with complex congenital heart defects palliated by connecting the systemic veins directly to the pulmonary circulation are known to develop hepatopulmonary syndrome (HPS). Although rare, HPS can develop following the Fontan operation. To present and analyse the CT findings of HPS in patients with a Fontan circulation. From May to December 2005, six patients with HPS following the completion of a Fontan circulation were evaluated. CT findings were reviewed and were compared with angiographic findings. All six patients showed unilateral involvement. All patients except one had inferior vena cava (IVC) interruption with azygos continuation. CT scans showed abnormal vascular dilatation in one lung, and properly demonstrated the anatomy causing the hepatic venous blood to flow preferentially into one lung. These CT findings correlated well with the angiography findings. HPS that develops after the Fontan procedure is typically unilateral and is often associated with IVC interruption and azygos or hemiazygos continuation. CT demonstrates dilatation of pulmonary vessels in the affected lung and may be able to demonstrate the underlying anatomical cause for the predilection of hepatic venous flow to the contralateral lung.

To prospectively evaluate the accuracy of hepatic artery diameter and hepatic artery diameter-to-portal vein diameter ratio for ultrasonographic (US) diagnosis of biliary atresia, with cholangiographic or clinical information as reference standard.Institutional review board approval and informed consent were obtained. US was performed in 68 neonates and infants with cholestatic jaundice (mean age, 61 days; male-to-female ratio, 38:30). Biliary atresia (n = 38) was confirmed with cholangiography, and hepatitis (n = 30) was diagnosed with clinical (n = 24) or cholangiographic (n = 6) findings. Diameter of the right hepatic artery was measured with US. Right hepatic artery diameter-to-right portal vein diameter ratio was measured to determine relative enlargement of the hepatic artery. As a control group, 17 neonates and infants (mean age, 67 days; male-to-female ratio, 12:5) without jaundice underwent US of the porta hepatis. Statistical analysis was performed to compare US parameters among three groups with one-way analysis of variance. Optimal cutoff values of the hepatic artery diameter and hepatic artery diameter-to-portal vein diameter ratio for biliary atresia diagnosis were obtained with receiver operating characteristic analysis.The diameter of the right hepatic artery in biliary atresia group (1.9 mm +/- 0.4 [standard deviation]) was significantly larger than that in the hepatitis (1.4 mm +/- 0.3) and control (1.2 mm +/- 0.2) groups (P.001). Hepatic artery diameter-to-portal vein diameter ratio in the biliary atresia group (0.52 +/- 0.12) was larger than that in hepatitis (0.40 +/- 0.07) and in control (0.40 +/- 0.10) groups (P.001). Optimum cutoff values for diagnosis of biliary atresia were 1.5 mm (sensitivity, 92%; specificity, 87%; accuracy, 89%) for hepatic artery diameter and 0.45 for hepatic artery diameter-to-portal vein diameter ratio (sensitivity, 76%; specificity, 79%; accuracy, 78%).Measurement of hepatic artery diameter can be helpful in the US diagnosis of biliary atresia.

Objective: To investigate the usefulness of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion MRI for the evaluation of femoral head ischemia. Materials and Methods: Unilateral femoral head ischemia was induced by selective embolization of the medial circumflex femoral artery in 10 piglets. All MRIs were performed immediately (1 hour) and after embolization (1, 2, and 4 weeks). Apparent diffusion coefficients (ADCs) were calculated for the femoral head. The estimated pharmacokinetic parameters (Kep and Ve from two-compartment model) and semi-quantitative parameters including peak enhancement, time-to-peak (TTP), and contrast washout were evaluated. Results: The epiphyseal ADC values of the ischemic hip decreased immediately (1 hour) after embolization. However, they increased rapidly at 1 week after embolization and remained elevated until 4 weeks after embolization. Perfusion MRI of ischemic hips showed decreased epiphyseal perfusion with decreased Kep immediately after embolization. Signal intensitytime curves showed delayed TTP with limited contrast washout immediately post-embolization. At 1−2 weeks after embolization, spontaneous reperfusion was observed in ischemic epiphyses. The change of ADC (p = 0.043) and Kep (p = 0.043) were significantly different between immediate (1 hour) after embolization and 1 week post-embolization. Conclusion: Diffusion MRI and pharmacokinetic model obtained from the DCE-MRI are useful in depicting early changes of perfusion and tissue damage using the model of femoral head ischemia in skeletally immature piglets. Index terms: Diffusion-weighted imaging; Dynamic contrast enhanced MRI; Femoral head ischemia

To evaluate prospectively the hemodynamic state of the left renal vein with Doppler ultrasonography (US) and venography in pediatric patients with varicocele to assess the "nutcracker phenomenon."The institutional review board considered this study ethically sound, and parental informed consent was obtained for all subjects. Doppler US of the left renal vein was performed in 27 consecutive boys with varicocele (age range, 7-15 years; mean, 11.9 years) and in 20 boys without varicocele as control subjects (age range, 7-17 years; mean, 11.4 years). Doppler US was used to evaluate left renal vein diameters and peak velocities in the proximal left renal vein near the renal hilum and in the left renal vein between the aorta and superior mesenteric artery (aortomesenteric portion). The diameter ratios and peak velocity ratios between two sites were obtained. For statistical comparison of results, the t test was used. Left renal venography and renocaval pressure measurement were performed in 13 patients with varicocele. The Fisher exact test was used to evaluate the associations between the nutcracker phenomenon (renocaval pressure gradient/=3 mm Hg) and the development of collateral veins.The diameters of the proximal left renal vein and the peak velocities in the aortomesenteric portion of the left renal vein were significantly different between the varicocele group and the control group (P.001). The diameter ratios (5.7 +/- 1.8 [standard deviation]) and peak velocity ratios (5.2 +/- 2.6) in patients with varicocele were significantly higher than those in control subjects (3.5 +/- 1.0 and 3.1 +/- 0.8, respectively) (P.005). According to findings at left renal venography (n = 13), 10 patients (77%) met the criteria for the nutcracker phenomenon. The nutcracker phenomenon was significantly associated with the development of collateral veins (P = .035).Doppler US and venography of the left renal vein can show hemodynamic changes of the left renal vein and depict the presence of the nutcracker phenomenon in pediatric varicocele.

We sought to determine whether torsed testis viability can be evaluated by ultrasonography (US) including power Doppler US in an experimental model of acute testicular torsion.Eighteen rats underwent unilateral 540 degrees testicular torsion and contralateral orchiopexy. Gray-scale and power Doppler US were performed 24 hours later. We evaluated echogenicity, intratesticular vascular flow, and testis size. Echogenicity and intratesticular vascular flow were quantitatively analyzed by using a visual scale and computer-based analysis. After US, detorsion was performed in torsed testes, and 6 days after detorsion testes were excised to determine testicular viability, which was determined using gross and microscopic findings. US findings before detorsion were correlated with testicular viability.At US performed 24 hours after testicular torsion, all viable testes (n = 7) were homogeneous and isoechoic versus contralateral testes. In nonviable testes (n = 11), lower (82%) and heterogeneous (73%) echogenicities were seen on gray-scale US. Intratesticular vascular flow was preserved in 86% of viable testes. In nonviable testes, no intratesticular vascularity was observed in 82%, and intermittent, peripheral blood flow was detected in the remaining 18%. Intratesticular focal lesions were observed in 45% of nonviable testis. Quantitative analysis showed a statistically significant difference between viable and nonviable testes in terms of testicular echogenicity and intratesticular vascular flow.Preoperative US including power Doppler examination can predict testicular viability in testicular torsion. Echogenicity of nonviable testes was found to be hypoechoic and inhomogeneous. Power Doppler examination showed no or intermittent peripheral blood flow in nonviable testes.

MRI and FDG-PET may predict the histological grading of paediatric brain-stem gliomas.To assess MRI findings and metabolic imaging using FDG-PET of brain-stem gliomas based on histological grading.Included in the study were 20 paediatric patients (age 3-14 years, mean 8.2 years) with brain-stem glioma (five glioblastomas, ten anaplastic astrocytomas and five low-grade astrocytomas). MR images were assessed for the anatomical site of tumour origin, focality, pattern of tumour growth, and enhancement.All glioblastomas were located in the pons and showed diffuse pontine enlargement with focally exophytic features. Eight anaplastic astrocytomas were located in the pons and demonstrated diffuse pontine enlargement without exophytic features. Low-grade astrocytomas were located in the pons, midbrain or medulla and showed focally exophytic growth features and peripheral enhancement. In 12 patients in whom FDG-PET was undertaken, glioblastomas showed hypermetabolic or hypometabolic lesions, anaplastic astrocytomas showed no metabolic change or hypometabolic lesions and low-grade astrocytomas showed hypometabolism compared with the cerebellum.MRI findings correlated well with histological grading of brain-stem gliomas and MRI may therefore predict the histological grading. FDG-PET may be helpful in differentiating between anaplastic astrocytoma and glioblastomas among high-grade tumours.

Hepatocellular carcinoma only rarely occurs in Alagille syndrome. Here, we report on three cases of hepatocellular carcinoma associated with Alagille syndrome. All three patients were boys and presented with jaundice. In addition, they had the characteristic facial appearance of Alagille syndrome with cardiac, vertebral, and eye anomalies, and all had passed acholic stools from the neonatal period. Liver biopsies were diagnosed as bile duct paucity, compatible with Alagille syndrome in two cases, but the third case showed marked bile duct proliferation at the initial liver biopsy when 7 months old, which made diagnosis difficult. Eventually, all three cases progressed to biliary cirrhosis and hepatocellular carcinoma, which occurred at 17 months, 4 years, and 7 years, respectively. Because of the unusual liver histology and early onset of hepatocellular carcinoma, careful clinicopathologic correlations and close monitoring are required for the diagnosis of Alagille syndrome and for the early detection of hepatocellular carcinoma.

Background: Necrotizing enterocolitis (NEC) is the most common gastrointestinal emergency in neonatal intensive care units. Ultrasonographic findings in early-stage NEC have not been described. Objective: To assess the diagnostic value of ultrasonography for the diagnosis and monitoring of patients with NEC. Materials and methods: We evaluated the sonographic findings of early stages of NEC in 40 neonates who were clinically diagnosed with NEC when they were 2–28 days old. Their average gestational age was 32 weeks, and their mean weight was 1,850 g. All of the patients showed signs of bowel distention on abdominal radiography, with no evidence of pneumatosis intestinalis. We performed bowel sonography in all patients (n = 40), as well as in ten healthy neonates who served as a control group. The studies were conducted with a 10-MHz linear transducer from February 2003 to January 2004. We evaluated the echogenicity of the bowel wall, involved region, ascites, and portal venous gas at both initial and follow-up examinations. We divided the patients into two groups according to the bowel wall echogenicity pattern, group I with echogenic dots in the bowel wall and group II with dense granular echogenicities in the bowel wall. In order to identify any correlations between the ultrasonography and clinical findings, we evaluated the duration of parenteral feeding (NPO) in each group and compared two groups by means of a statistical analysis (Mann–Whitney test). Results: All of the neonates in the control group (n = 10) presented normal bowel wall echogenicity; the patients with NEC presented echogenic dots in 16 patients (40%) and dense granular echogenicities in 24 patients (60%). Portal venous gas was absent in all patients. On the follow-up examinations, the echogenicity of the bowel wall and ascites decreased in 37 patients (93%). The duration of NPO was 11.1 ± 6.6 days in group I and 16.5 ± 7.2 days in group II (P < 0.05). Conclusion: Echogenic dots or dense granular echogenicities in the bowel wall can be seen in patients with early-stage NEC. Bowel sonography can be helpful for the early diagnosis and monitoring of patients with NEC.

To assess the magnetic resonance (MR) features of fat graft interposition in experimentally induced growth plate injury, to correlate these features with histologic findings, and to compare the growth disturbances of fat-grafted and nonfat-grafted growth plate injuries.The growth plate injury model was created in 20 skeletally immature rabbits. In 14 rabbits, a bilateral growth plate defect was made in the medial half of the proximal tibia. The defect of the right tibia was filled with autologous fat; the left tibia was left empty. In another 6 rabbits, a unilateral growth plate defect was created with (n = 3) or without (n = 3) fat graft interposition in the right tibia. MR imaging was performed at 2, 4, and 12 weeks postoperatively using a 1.5-T MR unit. T1-weighted images, T2-weighted images, gradient echo images, and contrast-enhanced T1-weighted images were obtained in the coronal plane. The authors evaluated the MR features of the growth plate defects with or without fat graft, and the remaining growth plate. The length and angulation of the grafted tibia were compared with those of the nonfat-grafted tibia. RESULTS At 2 weeks postoperatively, the grafted area showed low signal intensity mixed with high signal intensity (71%) on T1-weighted imaging. At 2 weeks, most of the growth plate defect in the control animals showed low signal intensity in all image sequences. At 4 weeks, most of the grafted area showed low signal intensity on T2-weighted imaging. A bone bridge was revealed in 15% of the grafted tibia and in 62% of the control animals at 4 weeks. On gradient echo images, high signal intensity of the remaining growth plate was preserved in grafted tibias, but in the control animals this became invisible 4 weeks postoperatively. At 12 weeks, most of growth plate defect area became isointense on all image sequences in grafted tibia and in the control animals. Histologically, the fat-grafted area was replaced by fibrous connective tissues with thin, trabecular bone formation. Growth plate defects of the control animals were filled with mature fatty marrow with trabecular bone formation. The varus angle and medial length of the tibia were significantly different between fat-grafted tibias at 4 weeks and 12 weeks postoperatively.MR imaging was helpful for evaluating growth plate modifications and subsequent changes after fat graft interposition. Fat graft interposition had a role in reducing growth disturbance in growth plate injury.

Dysmyelinating diseases, or leukodystrophies, encompass a wide spectrum of inherited neurodegenerative disorders affecting the integrity of myelin in the brain and peripheral nerves. Most of these disorders fall into one of three categories-lysosomal storage diseases, peroxisomal disorders, and diseases caused by mitochondrial dysfunction-and each leukodystrophy has distinctive clinical, biochemical, pathologic, and radiologic features. Magnetic resonance (MR) imaging has become the primary imaging modality in patients with leukodystrophy and plays an important role in the identification, localization, and characterization of underlying white matter abnormalities in affected patients. MR imaging has also been extensively used to monitor the natural progression of various white matter disorders and the response to therapy. Although the MR imaging features of leukodystrophy are often nonspecific, systematic analysis of the finer details of disease involvement may permit a narrower differential diagnosis, which the clinician can then further refine with knowledge of patient history, clinical testing, and metabolic analysis.

We present the MR findings of hepatic choriocarcinoma in a 2-week-old infant. Two masses of heterogeneous signal intensity were evident; one was an extensive mass on the left side of the liver and the other was a "daughter" nodule in the right lobe. Peripheral portions of the masses were hyperintense on T1-weighted imaging (T1WI) and T2-weighted imaging (T2WI) suggesting subacute hemorrhage. Central portions of the masses were hypointense on T1WI and bright on T2WI. T1-weighted postgadolinium imaging showed peripheral enhancement of both tumor nodules. The infant's mother had normal serum beta-human chorionic gonadotropin levels and pelvic CT.