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Background: Sepsis predisposes full-term infants to necrotizing enterocolitis (NEC). As such, experimental induction of NEC was applied to a sepsis model to evaluate the potential role of US in the early diagnosis of NEC in full-term infants. Objective: To evaluate the resistive index (RI) of the superior mesenteric artery (SMA) on Doppler sonography in experimentally induced sepsis and correlate it with the pathological findings. Materials and methods: Fifteen 1-week-old New Zealand white rabbits (control group n = 3, sepsis group n = 12) were used in this study. We injected 1 mg/kg of E. coli O55-B5 lipopolysaccharide (LPS) into 12 rabbits to induce sepsis. Then we conducted grayscale evaluation of the caliber of the abdominal aorta as well as bowel wall thickness and echogenicity. In addition, we measured peak systolic and end-diastolic velocities and SMA RI on Doppler sonography. Pathological findings were analyzed and correlated with RI readings. Peak systolic and end-diastolic velocities and SMA RI values were analyzed statistically at each hour using the Wilcoxon rank sum test; the control and sepsis groups were compared using the Mann-Whitney test. Results: The bowel wall thickness in the sepsis group was significantly increased after LPS injection. The caliber of the abdominal aorta in the sepsis group was significantly decreased after LPS injection. There were echogenic foci (<10 in axial plane) in the bowel wall after LPS injection. Peak systolic velocity in the sepsis group was not significantly changed, but end-diastolic velocity was decreased. SMA RIs in the sepsis group were significantly increased post-LPS injection from baseline. In the control group there were no significant changes in bowel wall thickness, abdominal aorta caliber, bowel wall echogenicity or peak systolic and end-diastolic velocities and RIs. Pathologically, eight of the 12 rabbits in the sepsis group showed grade 1 intestinal injury, three showed grade 2 injury and one showed grade 3 injury. SMA RIs were higher in grades 2 and 3 than in grade 1 when measured at 2 h and 4 h. Conclusion: Sepsis caused necrotic injury in the animal models, and these findings were accompanied by significant changes on Doppler US. These findings could facilitate early detection of intestinal injury in septic infants with NEC. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: Nutcracker syndrome is characterized by gross haematuria caused by left renal vein (LRV) entrapment. Objective: To assess the role of LRV ultrasonography in the diagnosis of the nutcracker syndrome in children. Materials and methods: Twelve children (eight male, four female; mean age 12.8 years) with venographically confirmed nutcracker syndrome (LRV-IVC pressure gradient ≥3 mm Hg) underwent LRV sonography including Doppler spectral analysis ( n=7). The diameter and peak velocity (PV) were measured at two sites of the LRV (renal hilum and aortomesenteric portion). The US findings of nutcracker syndrome were compared with those of 20 control subjects using the t-test. We identified the optimal cut-off value of the US parameters for the diagnosis of the nutcracker syndrome using ROC analysis. Results: The PV at the aortomesenteric portion and the ratio of the PV between the two measured points showed significant differences between the two groups ( P<0.0001). The optimum cut-off values were found to be 4.7 for the PV ratio (sensitivity 100%, specificity 90%, accuracy 93%), and 93 cm/s for the PV at the aortomesenteric portion (sensitivity 100%, specificity 85%, accuracy 89%). Conclusion: LRV sonography, including Doppler spectral analysis, can demonstrate LRV entrapment haemodynamically. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Inflammatory myofibroblastic tumour of the liver is a rare disease in children and is characterized by an inflammatory mass of uncertain aetiology which simulates a true neoplasm, often resulting in a diagnostic dilemma. We report a pathologically proven case of inflammatory myofibroblastic tumour of the liver in a 14-month-old boy with jaundice. CT and MRI showed an ill-defined, homogeneously enhancing mass located in the hilar portion of the liver with biliary obstruction. He underwent percutaneous transhepatic biliary drainage to relieve obstructive jaundice, followed by lobectomy and, finally, liver transplantation. [ABSTRACT FROM AUTHOR]

Posterior circulation infarction is uncommon in children. We describe the clinical presentation and radiological findings in two children with cerebellar infarction resulting from dissection of the vertebral artery. We emphasize that vertebral artery injury should be considered in a child with acute symptoms and signs of ischaemia in the posterior circulation. MRI and MRA may be helpful in the diagnosis of cerebellar infarction and vertebral artery abnormality. [ABSTRACT FROM AUTHOR]

We present two cases of granulocytic sarcoma of the cervical lymph nodes with central necrosis as an initial manifestation of childhood leukaemia, focusing on the imaging features. Recognition of the CT and MR imaging findings of granulocytic sarcoma involving the cervical lymph nodes assists the differential diagnosis of noninfective lymphadenopathy in children. [ABSTRACT FROM AUTHOR]

A correction to the article about magnetic resonance (MR) and computed tomography (CT) features describing central skull base lymphoma in children that was published in the 2008 issue is presented.