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Anterior cruciate ligament (ACL) injuries are increasingly common in adolescents, and injuries in this age group are associated with many unique challenges. Recent large animal studies suggest that the size and function of the major bundles of the ACL change differently throughout skeletal growth. To better aid clinical treatment of pediatric partial ACL tears and better predict outcomes from age-specific treatments, there is a need to measure changes in ACL bundle size in humans during growth. As such, the objective of this study was to compare changes in the length and cross-sectional area of the ACL and its primary bundles in adolescent human subjects. MRI scans were analyzed to determine the visibility and integrity of the ACL and its anteromedial and posterolateral bundles. MRI scans were considered from a retrospective database of subjects ranging from 10-18 years of age. The ACL and its anteromedial and posterolateral bundles were segmented and reconstructed into 3D models, and length and cross-sectional area (CSA) were calculated. Total ACL length and CSA were greater in males compared to females, with a statistically significant interaction between age and sex for CSA. Sex had a significant effect on the CSA of both bundles. Interestingly, these sex dependent differences emerge with moderate to large effect sizes (range: d=0.50 to d=1.23) beginning around 13 years of age. With considerations of ACL bundle structure-function relationships previously established in preclinical animal models, these findings may point towards biomechanical changes in the adolescent human ACL.

Pediatric anterior cruciate ligament (ACL) injuries are on the rise, and females experience higher ACL injury risk than males during adolescence. Studies in skeletally immature patients indicate differences in ACL size and joint laxity between males and females after the onset of adolescence. However, functional data regarding the ACL and its anteromedial and posterolateral bundles in the pediatric population remain rare. Therefore, this study uses a porcine model to investigate the sex-specific morphology and biomechanics of the ACL and its bundles throughout skeletal growth. Hind limbs from male and female Yorkshire pigs aged early youth to late adolescence were imaged using magnetic resonance imaging to measure the size and orientation of the ACL and its bundles, then biomechanically tested under anterior-posterior drawer using a robotic testing system. Joint laxity decreased (p

BACKGROUND Millennial digital learners value meaningful work, immediate feedback, collaborative communication and technology implementation. A student-produced digital imaging teaching case file-centric flipped curriculum offers these benefits. Our questions included: (i) is a cloud-based website platform supporting the online publication of student-selected and student-submitted teaching cases feasible; and (ii) what were the impressions of students of this educational intervention? METHODS An open-source medical student-centric radiology website was created with limited-access cloud upload capability, with site analytics continuously recorded. Medical students submitted de-identified radiology cases on a topic of their choosing, for peer review and publication. By making the host site publicly accessible, we empowered students to list their publication(s) on resumes. Following six blocks of the 2018/19 academic year after implementation, an electronic survey was sent to the eligible medical student cohort who had were enrolled in a radiology elective in order to assess the effectiveness of the intervention (n = 107). RESULTS The survey response rate was 52% (n = 56), of which 98% participated (n = 55) and 75% completed a teaching file (n = 42). The students assessed their ability to systematically review imaging, communicate pertinent clinical information, appropriately order imaging, correctly use the ACR Appropriateness Criteria® , consider procedure costs, consider procedure risks, consider procedure benefits, evaluate effectiveness and identify who to direct questions to regarding correct study. Students reported answers on a seven-point Likert scale. Data scores ranged from 5.28 (agree) to 6.71 (strongly agree) across all categories. CONCLUSIONS Our successful student-developed teaching file takes advantage of digital radiology and the educational tools favoured by millennials. This activity meets core competencies in self-directed and lifelong learning.

ACL injuries are becoming increasingly common in children and adolescents, but little is known regarding age-specific ACL function in these patients. To improve our understanding of changes in musculoskeletal tissues during growth and given the limited availability of pediatric human cadaveric specimens, tissue structure and function can be assessed in large animal models, such as the pig.Using cadaveric porcine specimens ranging throughout skeletal growth, we aimed to assess age-dependent changes in (1) joint kinematics under applied AP loads and varus-valgus moments, (2) biomechanical function of the ACL under the same loads, (3) the relative biomechanical function of the anteromedial and posterolateral bundles of the ACL; and (4) size and orientation of the anteromedial and posterolateral bundles.Stifle joints (analogous to the human knee) were collected from female Yorkshire crossbreed pigs at five ages ranging from early youth to late adolescence (1.5, 3, 4.5, 6, and 18 months; n = 6 pigs per age group, 30 total), and MRIs were performed. A robotic testing system was used to determine joint kinematics (AP tibial translation and varus-valgus rotation) and in situ forces in the ACL and its bundles in response to applied anterior tibial loads and varus-valgus moments. To see if morphological changes to the ACL compared with biomechanical changes, ACL and bundle cross-sectional area, length, and orientation were calculated from MR images.Joint kinematics decreased with increasing age. Normalized AP tibial translation decreased by 44% from 1.5 months (0.34 ± 0.08) to 18 months (0.19 ± 0.02) at 60° of flexion (p0.001) and varus-valgus rotation decreased from 25° ± 2° at 1.5 months to 6° ± 2° at 18 months (p0.001). The ACL provided the majority of the resistance to anterior tibial loading at all age groups (75% to 111% of the applied anterior force; p = 0.630 between ages). Anteromedial and posterolateral bundle function in response to anterior loading and varus torque were similar in pigs of young ages. During adolescence (4.5 to 18 months), the in situ force carried by the anteromedial bundle increased relative to that carried by the posterolateral bundle, shifting from 59% ± 22% at 4.5 months to 92% ± 12% at 18 months (data for 60° of flexion, p0.001 between 4.5 and 18 months). The cross-sectional area of the anteromedial bundle increased by 30 mm throughout growth from 1.5 months (5 ± 2 mm) through 18 months (35 ± 8 mm; p0.001 between 1.5 and 18 months), while the cross-sectional area of the posterolateral bundle increased by 12 mm from 1.5 months (7 ± 2 mm) to 4.5 months (19 ± 5 mm; p = 0.004 between 1.5 and 4.5 months), with no further growth (17 ± 7 mm at 18 months; p = 0.999 between 4.5 and 18 months). However, changes in length and orientation were similar between the bundles.We showed that the stifle joint (knee equivalent) in the pig has greater translational and rotational laxity in early youth (1.5 to 3 months) compared with adolescence (4.5 to 18 months), that the ACL functions as a primary stabilizer throughout growth, and that the relative biomechanical function and size of the anteromedial and posterolateral bundles change differently with growth.Given the large effects observed here, the age- and bundle-specific function, size, and orientation of the ACL may need to be considered regarding surgical timing, graft selection, and graft placement. In addition, the findings of this study will be used to motivate pre-clinical studies on the impact of partial and complete ACL injuries during skeletal growth.

OBJECTIVE: To examine the association between neonatal cranial ultrasound abnormalities among infants born extremely preterm and neurodevelopmental outcomes at ten years of age. STUDY DESIGN: In a multi-center birth cohort of infants born at < 28 weeks’ gestation, 889 of 1198 survivors were evaluated for neurological, cognitive, and behavioral outcomes at 10 years of age. Sonographic markers of white matter damage (WMD) included echolucencies in the brain parenchyma and moderate to severe ventricular enlargement. Neonatal cranial ultrasound findings were classified as: intraventricular hemorrhage (IVH) without WMD, IVH with WMD, WMD without IVH, and neither IVH nor WMD. RESULTS: WMD without IVH was associated with an increased risk of cognitive impairment (OR 3.5, 95% CI 1.7, 7.4), cerebral palsy (OR 14.3, 95% CI 6.5, 31.5), and epilepsy (OR 6.9; 95% CI 2.9, 16.8). Similar associations were found for WMD accompanied by IVH. Isolated IVH was not significantly associated these outcomes. CONCLUSIONS: Among children born extremely preterm, cranial ultrasound abnormalities, particularly those indicative of WMD, are predictive of neurodevelopmental impairments at 10 years of age. The strongest associations were found with cerebral palsy.

Pediatric anterior cruciate ligament (ACL) injuries are on the rise, and females experience higher ACL injury risk than males during adolescence. Studies in skeletally immature patients indicate differences in ACL size and joint laxity between males and females after the onset of adolescence. However, functional data regarding the ACL and its anteromedial and posterolateral bundles in the pediatric population remain rare. Therefore, this study uses a porcine model to investigate the sex-specific morphology and function of the ACL and its bundles throughout skeletal growth. Hind limbs from male and female Yorkshire pigs aged early youth to late adolescence were imaged using magnetic resonance imaging to measure the size and orientation of the ACL and its bundles, then biomechanically tested under anterior-posterior drawer using a robotic testing system. Joint laxity decreased (pin situ ACL stiffness correlated with cross-sectional area across skeletal growth (r2=0.75, p2=0.64, p

The imaging evaluation of cystic fibrosis currently relies on chest radiography or computed tomography. Recently, digital chest tomosynthesis has been proposed as an alternative. We have developed a stationary digital chest tomosynthesis (s-DCT) system based on a carbon nanotube (CNT) linear x-ray source array. This system enables tomographic imaging without movement of the x-ray tube and allows for physiological gating. The goal of this study was to evaluate the feasibility of clinical CF imaging with the s-DCT system. CF patients undergoing clinically indicated chest radiography were recruited for the study and imaged on the s-DCT system. Three board-certified radiologists reviewed both the CXR and s-DCT images for image quality relevant to CF. CF disease severity was assessed by Brasfield score on CXR and chest tomosynthesis score on s-DCT. Disease severity measures were also evaluated against subject pulmonary function tests. Fourteen patients underwent s-DCT imaging within 72 h of their chest radiograph imaging. Readers scored the visualization of proximal bronchi, small airways and vascular pattern higher on s-DCT than CXR. Correlation between the averaged Brasfield score and averaged tomosynthesis disease severity score for CF was -0.73, p = 0.0033. The CF disease severity score system for tomosynthesis had high correlation with FEV1 (r = -0.685) and FEF 25–75% (r = -0.719) as well as good correlation with FVC (r = -0.582). We demonstrate the potential of CNT x-ray-based s-DCT for use in the evaluation of cystic fibrosis disease status in the first clinical study of s-DCT. • Carbon nanotube-based linear array x-ray tomosynthesis systems have the potential to provide diagnostically relevant information for patients with cystic fibrosis without the need for a moving gantry. • Despite the short angular span in this prototype system, lung features such as the proximal bronchi, small airways and pulmonary vasculature have improved visualization on s-DCT compared with CXR. Further improvements are anticipated with longer linear x-ray array tubes. • Evaluation of disease severity in CF patients is possible with s-DCT, yielding improved visualization of important lung features and high correlation with pulmonary function tests at a relatively low dose.

Aim To assess to what extent the blood concentrations of proteins with neurotrophic and angiogenic properties measured during the first postnatal month convey information about the risk of sonographically-identified brain damage among very preterm newborns. Methods Study participants were 1219 children who had a cranial ultrasound scan during their stay in the intensive care nursery and blood specimens collected on 2 separate days at least a week apart during the first postnatal month. Concentrations of selected proteins in blood spots were measured with electrochemiluminescence or with a multiplex immunobead assay and the risks of cranial ultrasound images associated with top-quartile concentrations were assessed. Results High concentrations of multiple inflammation-related proteins during the first 2 postnatal weeks were associated with increased risk of ventriculomegaly, while high concentrations of just 3 inflammation-related proteins were associated with increased risk of an echolucent/hypoechoic lesion (IL-6, IL-8, ICAM-1), especially on day 7. Concomitant high concentrations of IL6R and bFGF appeared to modulate the increased risks of ventriculomegaly and an echolucent lesion associated with inflammation. More commonly high concentrations of putative protectors/repair-enhancers did not appear to diminish these increased risks. Conclusion Our findings provide support for the hypothesis that endogenous proteins are capable of either protecting the brain against damage and/or enhancing repair of damage.

Musculoskeletal injuries in pediatric patients are on the rise, including significant increases in anterior cruciate ligament (ACL) injuries. Previous studies have found major anatomical changes during skeletal growth in the soft tissues of the knee. Specifically, the ACL and the posterior cruciate ligament (PCL) change in their relative orientation to the tibial plateau throughout growth. In order to develop age-specific treatments for ACL injuries, the purpose of this study was to characterize orientation changes in the cruciate ligaments of the Yorkshire pig, a common pre-clinical model, during skeletal growth in order to verify the applicability of this model for pediatric musculoskeletal studies. Hind limbs were isolated from female Yorkshire pigs ranging in age from newborn to late adolescence and were then imaged using high field strength magnetic resonance imaging. Orientation changes were quantified from the magnetic resonance images using image segmentation software. Statistically significant increases were found in the coronal and sagittal angles of the ACL relative to the tibial plateau during pre-adolescent growth. Additional changes were observed in the PCL angle, Blumensaat angle, intercondylar roof angle, and the aspect ratio of the intercondylar notch. Only the sagittal angle of the ACL relative to the tibial plateau experienced statistically significant changes through late adolescence. The age-dependent properties of the ACL and PCL in the female pig mirrored results found in female human patients, suggesting that the porcine model may provide a pre-clinical platform to study the cruciate ligaments during skeletal growth. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2725-2732, 2017.

Hybrid PET/MR imaging systems have recently become available for clinical practice. The simultaneous physiologic and anatomic imaging offers the potential to reduce radiation dose and other advantages for pediatric patients. Issues more unique to pediatric imaging, however, must also be addressed, including imaging time and disease sensitivity. Combined with newer tracers and a concerted multidisciplinary effort, the approach has the potential to substantially improve the imaging of a variety of pediatric diseases.

Neuroblastoma and protein losing enteropathy (PLE) are diagnoses commonly seen by oncologists and gastroenterologists, respectively. The concurrence of these 2 entities is rare, and not well explained. We describe the sixth case of PLE in a child with neuroblastoma, and the first for which genetic information is available. Tumor DNA had a mutation in the PTPN11 gene, which has been described in neuroblastoma, and in Noonan syndrome-a diagnosis in which neuroblastoma and PLE independently have been reported. Constitutional DNA was normal. Genetic studies in future patients will be needed to support the link between neuroblastoma and PLE.

In recent years, there has been a movement toward more judicious use of computed tomography (CT) imaging in an attempt to limit exposure of pediatric patients to ionizing radiation. The Image Gently Alliance and like-minded movements began advocating for safe and high-quality pediatric imaging worldwide in the late 2000s. In the context of these efforts, we evaluate CT utilization rates in the pediatric emergency department at a major academic medical center. We tracked utilization in several categories of CT, magnetic resonance imaging (MRI) and ultrasonography (US) between July 2008 and June 2017 and compared them with utilization rates from 2000 to 2006. A total of 4,955 pediatric patients underwent a total of 5,973 CT scans, 2,775 US studies and 293 MRI scans while in the pediatric emergency department during the 2008–2017 study period. We observed decreases in CT scans across all categories, ranging from a 19% decrease in abdominal CT to a 66% decrease in chest CT. Relatively greater decreases in CT scans were observed in patients younger than 3 years of age as compared to older children and adolescents. Abdominal and pelvic US increased. Brain MRI also increased over the final two years of the study. CT utilization decreased throughout the 2008–2017 study period.

Prior studies have analyzed growth of musculoskeletal tissues between species or across body segments; however, little research has assessed the differences in similar tissues within a single joint. Here we studied changes in the length and cross-sectional area of four ligaments and tendons, (anterior cruciate ligament, patellar tendon, medial collateral ligament, lateral collateral ligament) in the tibiofemoral joint of female Yorkshire pigs through high-field magnetic resonance imaging throughout growth. Tissue lengths increased by 4-to 5-fold from birth to late adolescence across the tissues while tissue cross-sectional area increased by 10-20-fold. The anterior cruciate ligament and lateral collateral ligament showed allometric growth favoring change in length over change in cross-sectional area while the patellar tendon and medial collateral ligament grow in an isometric manner. Additionally, changes in the length and cross-sectional area of the anterior cruciate ligament did not increase as much as in the other ligaments and tendon of interest. Overall, these findings suggest that musculoskeletal soft tissue morphometry can vary within tissues of similar structure and within a single joint during post-natal growth.

Objectives/Hypothesis Determine whether quantitative geometric measures and a computational fluid dynamic (CFD) model derived from medical imaging of children with subglottic stenosis (SGS) can be effective diagnostic and treatment planning tools. Study Design Retrospective chart and imaging review in a tertiary care hospital. Methods Computed tomography scans (n = 17) of children with SGS were analyzed by geometric and CFD methods. Polysomnograms (n = 15) were also analyzed. Radiographic data were age/weight flow normalized and were compared to an atlas created from radiographically normal airways. Five geometric, seven CFD, and five polysomnography measures were analyzed. Statistical analysis utilized a two-sample t test with Bonferroni correction and area under the curve analysis. Results Two geometric indices (the ratio of the subglottic to midtracheal airway, the percent relative reduction of the subglottic airway) and one CFD measure (the percent relative reduction of the hydraulic diameter of the subglottic airway) were significant for determining which children with SGS received surgical intervention. Optimal cutoffs for these values were determined. Polysomnography, the respiratory effort-related arousals index, was significant only prior to Bonferroni correction for determining which children received surgical intervention. Conclusions Geometric and CFD variables were sensitive at determining which patients with SGS received surgical intervention. Discrete quantitative assessment of the pediatric airway was performed, yielding preliminary data regarding possible objective thresholds for surgical versus nonsurgical treatment of disease. This study is limited by its small, retrospective, single-institution nature. Further studies to validate these findings and possibly optimize treatment threshold recommendations are warranted. Level of Evidence 4 Laryngoscope, 2015

Multiple radiographic studies are used to diagnose aspiration and dysphagia in children. Imaging studies, such as chest radiographs and computed tomography of the chest, are not specifically used for diagnosis of aspiration, but can show evidence of damage suggestive of aspiration, and can also be useful in determining the extent of lung injury from chronic aspiration. Chest radiographic findings of aspiration include hyperinflation, peribronchial thickening, and localized infiltrates. Chest CT is more sensitive than chest x-ray for early changes from aspiration, and characteristic findings include bronchial wall thickening, air trapping, and eventually bronchiectasis, honeycombing, and diffuse ground-glass opacities. While videofluoroscopic swallowing study is the most commonly used radiographic modality for diagnosis of aspiration, other studies including gastroesophageal scintigraphy and the radionuclide salivagram may also be used for detecting aspiration. Poor sensitivity of these studies and poor agreement between tests have limited their clinical utility and point to the difficulty of establishing a gold standard radiographic study for diagnosis of aspiration.

The United States Food and Drug Administration (FDA) recently approved an ultrasound (US) contrast agent for intravenous and intravesical administration in children. Survey the usage, interest in and barriers for contrast-enhanced US among pediatric radiologists. The Contrast-Enhanced Ultrasound Task Force of the Society for Pediatric Radiology (SPR) surveyed the membership of the SPR in January 2017 regarding their current use and opinions about contrast-enhanced US in pediatrics. The majority (51.1%, 166) of the 325 respondents (26.7% of 1,218) practice in either a university- or academic affiliated group. The most widely used US contrast agent was Lumason® 52.3% (23/44). While lack of expertise and training were reported barriers, all respondents who are not currently using US contrast agents are considering future use. Interest in pediatric contrast US is very high. Education and training are needed to support members who plan to adopt contrast US into practice.

The practice of contrast-enhanced ultrasound in children is in the setting of off-label use or research. The widespread practice of pediatric contrast-enhanced US is primarily in Europe. There is ongoing effort by the Society for Pediatric Radiology (SPR) and International Contrast Ultrasound Society (ICUS) to push for pediatric contrast-enhanced US in the United States. With this in mind, the main objective of this review is to describe the status of US contrast agent safety in non-cardiac applications in children. The five published studies using pediatric intravenous contrast-enhanced US comprise 110 children. There is no mention of adverse events in these studies. From a European survey 948 children can be added. In that survey six minor adverse events were reported in five children. The intravesical administration of US contrast agents for diagnosis of vesicoureteric reflux entails the use of a bladder catheter. Fifteen studies encompassing 2,951 children have evaluated the safety of intravesical US contrast agents in children. A European survey adds 4,131 children to this group. No adverse events could be attributed to the contrast agent. They were most likely related to the bladder catheterization. The existing data on US contrast agent safety in children are encouraging in promoting the widespread use of contrast-enhanced US.

Musculoskeletal injuries in pediatric patients are on the rise, including significant increases in anterior cruciate ligament (ACL) injuries. Previous studies have found major anatomical changes during skeletal growth in the soft tissues of the knee. Specifically, the ACL and the posterior cruciate ligament (PCL) change in their relative orientation to the tibial plateau throughout growth. In order to develop age-specific treatments for ACL injuries, the purpose of this study was to characterize orientation changes in the cruciate ligaments of the Yorkshire pig, a common pre-clinical model, during skeletal growth in order to verify the applicability of this model for pediatric musculoskeletal studies. Hind limbs were isolated from female Yorkshire pigs ranging in age from newborn to late adolescence and were then imaged using high field strength magnetic resonance imaging. Orientation changes were quantified from the magnetic resonance images using image segmentation software. Statistically significant increases were found in the coronal and sagittal angles of the ACL relative to the tibial plateau during pre-adolescent growth. Additional changes were observed in the PCL angle, Blumensaat angle, intercondylar roof angle, and the aspect ratio of the intercondylar notch. Only the sagittal angle of the ACL relative to the tibial plateau experienced statistically significant changes through late adolescence. The age-dependent properties of the ACL and PCL in the female pig mirrored results found in female human patients, suggesting that the porcine model may provide a pre-clinical platform to study the cruciate ligaments during skeletal growth. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2725-2732, 2017.

To date, there are limited radiation dose data on CT-guided procedures in pediatric patients. Our goal was to quantify the radiation dose associated with pediatric CT-guided drain placement and follow-up drain evaluations in order to estimate effective dose. We searched the electronic medical record and picture archiving and communication system (PACS) to identify all pediatric (

The objective of this study is to characterize changes in computed tomography (CT) utilization in the pediatric emergency department (ED) over a 6-year period. CT scans ordered on pediatric (ages 0 to 17 years) ED patients from July 2000 to July 2006 were analyzed in five groups: head, cervical spine, chest, abdomen, and miscellaneous. Pediatric ED patient volume and triage acuity scores were determined. There were 6,073 CT scans performed on 4,138 pediatric patients in the ED during the study period. During this same period, 78,932 pediatric patients were evaluated in the ED. From 2000 to 2006, pediatric ED patient volume increased by 2%, while triage acuity remained stable. During this same period, head CT increased by 23%, cervical spine CT by 366%, chest CT by 435%, abdominal CT by 49%, and miscellaneous CT by 96%. Increases in CT utilization were most pronounced in adolescents ages 13 to 17 years. Increases in CT utilization in this age group met or exceeded increases seen in the adult population. In children less than 13 years of age, increases were substantially smaller. Pediatric ED CT utilization particularly in the adolescent population has increased at a rate far exceeding the growth in ED patient volume, mimicking the adult trend. This increase has occurred despite considerable discussion in the medical literature about the radiation risks of CT in the pediatric population and may reflect increased availability of CT, improvements in CT diagnostic capabilities, and increased desire on the part of physicians and patients for diagnostic certainty. Whether this increased utilization results in improved patient outcomes is uncertain and deserves further study.

To examine the extent to which weight gain and weight status in the first 2 years of life relate to the risk of neurodevelopmental impairment in extremely preterm infants.In a cohort of 1070 infants born between 23 and 27 weeks' gestation, we examined weight gain from 7-28 days of life (in quartiles) and weight z-score at 12 and 24 months corrected age (in 4 categories:-2; ≥-2,-1; ≥1,1; and ≥1) in relation to these adverse neurodevelopmental outcomes: Bayley-II mental development index55, Bayley-II psychomotor development index55, cerebral palsy, Gross Motor Function Classification System ≥1 (cannot walk without assistance), microcephaly. We adjusted for confounders in logistic regression, stratified by sex, and performed separate analyses including the entire sample, and excluding children unable to walk without assistance (motor impairment).Weight gain in the lowest quartile from 7-28 days was not associated with higher risk of adverse outcomes. Children with a 12-month weight z-score-2 were at increased risk for all adverse outcomes in girls, and for microcephaly and Gross Motor Function Classification System ≥1 in boys. However, excluding children with motor impairment attenuated all associations except that of weight z-score-2 with microcephaly in girls. Similarly, most associations of low weight z-score at 24 months with adverse outcomes were attenuated with exclusion of children with motor impairment.Excluding children who have gross motor impairment appears to eliminate the association of low weight status with neurodevelopmental impairments at 2 years in extremely preterm infants.

We analyzed the chest radiographs (CXRs) of 249 clinically healthy children, 230 from southwest Mexico City and 19 from Tlaxcala. In contrast to children from Tlaxcala, children from southwest Mexico City were chronically exposed to ozone levels exceeding the U.S. National Ambient Air Quality Standards for an average of 4.7 hr/day and to concentrations of particulate matter (PM) with aerodynamic diameters

HIV infection predisposes to cancer during childhood. In addition to the AIDS-defining non-Hodgkin lymphoma (NHL) and Kaposi sarcoma, a range of other lymphoid malignancies and solid tumors have been described. We report the first case of an HIV-positive child with thymic carcinoma in the setting of regressing thymic cysts. The tumor expressed CKIT but failed to respond to imatinab mesylate after a transient response to multiagent chemotherapy. This case extends the spectrum of pediatric malignancy in the setting of HIV and suggests that patients with presumed benign thymic cysts require ongoing surveillance. Pediatr Blood Cancer 2007;49:1004–1007. © 2005 Wiley-Liss, Inc.

The main role of the esophagus is to facilitate passage of food from the mouth to the stomach. A number of conditions can alter esophageal structure or function including congenital anomalies, trauma, infection, and neoplasm. This article reviews the anatomy, imaging evaluation, and common problems seen in the pediatric thoracic esophagus.

Primary pulmonary lymphangiectasia (PPL) is a rare disorder of unknown aetiology characterised by dilatation of the pulmonary lymphatics. PPL is widely reported to have a poor prognosis in the neonatal period and little is known about the clinical features of patients who survive the newborn period. The current authors report the outcome in nine patients diagnosed in infancy with PPL over a 15-yr period at a single university-based hospital clinic and followed for a median of 6 yrs. Although all of the patients initially experienced respiratory distress, respiratory symptoms improved in most patients after infancy and were notably better by the age of 6 yrs. Many patients had poor weight gain in the first years of life, which eventually improved. Radiological scans showed progressive resolution of neonatal infiltrates, but were characterised by hyperinflation and increased interstitial markings in older children. Most patients had evidence of bronchitis and grew pathogenic organisms from quantitative bronchoalveolar lavage culture. Pulmonary function tests showed predominantly obstructive disease that did not deteriorate over time. In conclusion, these results suggest that primary pulmonary lymphangiectasia does not have as dismal a prognosis as previously described and symptoms and clinical findings improve after the first year of life.

Southwest Metropolitan Mexico City (SWMMC) children are chronically exposed to complex mixtures of air pollutants. In a cross-sectional arm of our study, we investigated the association between exposure to SWMMC atmosphere and nasal abnormalities, hyperinflation, and interstitial markings assessed by chest X-rays, lung function changes, several serum cytokines, and endothelin-1 in 174 children aged 5-17 years vs. 27 control children residents in low-polluted areas. Control children had no nasal lesions, and only one child showed an abnormal chest X-ray. SWMMC children exhibited nasal abnormalities (22%), hyperinflation (67%), interstitial markings (49%), and a mild restrictive pattern by spirometry (10%). Interstitial markings were associated with a decrease in predicted values of FEF(25-75), FEF(75), and the FEV(1)/FVC ratio. Boys had a higher probability of developing interstitial markings with age (P = 0.004). Blood smear findings included toxic granulations in neutrophils and schistocytes. SWMMC children had more serum IL10 and IL6 and less IL8 than controls. In a longitudinal arm of our study, we found a significant seasonal drop in FVC and FEV(1) associated with a 6-month period of high ozone and PM(10) levels. Our data strongly suggest that a lifelong exposure to urban air pollution causes respiratory damage in children. Moreover, a cytokine network becomes imbalanced, with a shift towards upregulation of anti-inflammatory cytokines. Consequently, these children are potentially at risk for developing chronic lung disease and other systemic effects later in life.

Background Airway surface liquid (ASL) is difficult to sample. Lavage with an immiscible perfluorocarbon (PFC) liquid to recover ASL was evaluated in cats. Materials and Methods Six wild-type cats underwent bronchoscopic lavage with a PFC (perfluorohexane), with the bronchoscope wedged in the feline equivalent of the right lower lobe. Two cats (control animals) were lavaged with a saline vehicle only. Four procedures were performed on each animal at 2–3-week intervals. Ionic composition of ASL was determined by flame photometry. Results Cats lavaged with PFC showed significantly more acute respiratory distress than those lavaged with saline (respiratory rate following procedure: PFC, 47 ± 5 min−1 vs. saline, 27 ± 2 min−1, P 100 µL) which were sufficient for analysis. Mean (± SEM) ionic concentrations in these samples were Na+ 157·4 ± 14·5 mmol L−1, Cl− 150·5 ± 16·8 mmol L−1 and K+ 10·1 ± 1·7 mmol L−1. Conclusions Perfluorocarbon lavage can be used to collect unmodified ASL from the distal lung. However, repeated lavage with perfluorohexane was associated with significant pathological changes in this study.

Applications of MR imaging of the pediatric abdomen are expanding rapidly. New techniques of MR imaging, such as MRA or MRCP, are becoming commonplace. MR imaging is particularly helpful in the diagnosis and characterization of liver and biliary tree disease in children. Consistent and reproducible quality imaging is achieved with faster imaging sequences tailored to reduce motion artifacts. The lack of radiation, the ability to directly acquire multiple imaging planes, and the superior contrast resolution, particularly with the administration of gadolinium, have contributed to the acceptance of MR imaging as an invaluable tool in the pediatric age group.

Air pollution produces adverse health effects. The consequences of lifelong daily exposures to atmospheric pollutants upon the respiratory apparatus of healthy children are of considerable clinical importance. We investigated the association between exposure to a highly polluted urban environment with a complex mixture of air pollutants-ozone and particulate matter the predominant ones-and chest x-ray abnormalities in 59 healthy Mexican children who are lifelong residents of Southwest Metropolitan Mexico City (SWMMC), with a negative history of tobacco exposure and respiratory illnesses. Their clinical results and x-ray findings were compared to those of 19 Mexican control children, residents of a low-pollution area, with a similar negative history of tobacco exposure and respiratory illnesses. Ozone concentrations in SWMMC exceeded the U.S. Environmental Protection Agency (U.S. EPA) National Ambient Air Quality Standard (NAAQS) for O(3): 0.08 ppm as 1-h maximal concentration, not to be exceeded more than 4 times a year, on 71% of days in 1986 and 95% in 1997, with values as high as 0.48 ppm. Ozone maximal peaks are usually recorded between 2 and 5 pm coinciding with children's outdoor physical activities. Children in the control group reported no upper or lower respiratory symptomatology. Every SWMMC child complained of upper and/or lower respiratory symptoms, including epistaxis, nasal dryness and crusting, cough, shortness of breath, and chest discomfort. Children aged 7-13 yr had the most symptomatology, while 5- to 6-year olds and adolescents with the lowest number of statistically significant outdoor exposure hours had less respiratory symptoms. Bilateral symmetric mild lung hyperinflation was significantly associated with exposure to the SWMMC atmosphere (p = .0004). Chronic and sustained inhalation of a complex mixture of air pollutants, including ozone and particulate matter (PM), is associated with lung hyperinflation, suggestive of small airway disease, in a population of clinically healthy children and adolescents. Small airways are a target of air pollutants in SWMMC children, with ozone and PM being most likely responsible, based on experimental animal, controlled-chamber, and epidemiological data available. Our main concern is the potential likelihood for the development of chronic lung disease in this highly exposed population.

We evaluated the ability of current magnetic resonance (MR) scanning techniques to detect and stage neuroblastoma in children, using surgical and histopathologic correlation. We prospectively and retrospectively reviewed 16 MR examinations from 14 patients with neuroblastoma (13 patients) or ganglioneuroblastoma (1 patient) and compared these to computed tomography (CT) (5 patients) and pathology (all patients). Sequences included: precontrast T1-weighted and T2-weighted images, and gadolinium-enhanced T1-weighted images. The study time for each MR exam was also calculated. Five primary tumors were intrathoracic paraspinous masses, eight were adrenal, and 1 was presacral. Neural foraminal invasion was demonstrated on MR in four of 14 patients. Three of the four patients had undergone CT and neural foraminal invasion was shown in one. Vascular encasement was demonstrated in five of 14 patients on MR images. Three of the five patients had undergone CT and vascular involvement was shown in two. All cases of neural foramina invasion and vascular encasement were proven at surgery. There were no false positive or false negative MR studies of neural foraminal invasion or vascular encasement. Bone marrow invasion was shown in two of 14 patients on MR images which were confirmed by bone marrow aspirate. No false negative cases of bone marrow invasion was shown. In one patient, CT considered one neuroblastoma to be adrenal in location which was correctly shown to be intrathoracic on MR. The mean study time for MR imaging was 49 min. Current MR techniques are accurate at detecting and staging neuroblastoma, and coverage of chest, abdomen, and pelvis can be performed in less than one hour.

OBJECTIVES: Ehrlichiosis is a newly recognized tick-borne infection affecting both children and adults. The disease is usually mild, with flulike symptoms, but can be fatal. We present the chest radiographs and, in one case, the chest CT scan of all recognized pediatric cases of ehrlichiosis to date from our institution. CONCLUSION: Ehrlichiosis should be included in the differential diagnosis of acutely ill pediatric patients with a history of possible tick exposure and radiographic patterns of interstitial prominence, alveolar opacities, or consolidation that may be associated with pleural effusion.

Objective. The purpose of this paper is to review and categorize the CT appearances of primary and secondary intraperitoneal neoplasms in children. Materials and methods. We retrospectively reviewed the CT images of 14 cases of intraperitoneal neoplasms. They were reviewed for bowel wall thickening, mesenteric nodules, ascites, calcification, peritoneal nodules, omental caking, and contrast enhancement. Results. Computed tomography images of 14 cases of intraperitoneal neoplasms were evaluated: rhabdomyosarcoma (5), lymphoma (3), neuroblastoma (2), germ cell tumor (1), mesothelioma (1), Wilms tumor (1), and hepatocellular carcinoma (1). Nodular enhancement was seen in all cases, ascites in most, significant bowel wall thickening only with lymphoma, and calcification only with germ cell tumors. Omental caking was present both with rhabdomyosarcoma and lymphoma. Conclusions. While rare in pediatrics, intraperitoneal neoplasms occur in children, and CT is useful in identifying these peritoneal neoplasms.

A previously healthy 11-year-old girl presented with an 8-month history of anemia and left upper quadrant abdominal pain. US examination demonstrated a 9-cm cystic mass with a fluid-fluid level in the left upper quadrant with unclear organ of origin. Abdominal MR imaging demonstrated a complex cystic mass, likely arising from the stomach. Additional T2 hyperintense submucosal lesions were identified in the gastric wall. Surgical excision confirmed the diagnosis of multifocal gastric gastrointestinal stromal tumor (GIST). MR imaging was helpful in suggesting a gastric origin of the primary mass and in demonstrating multifocal disease within the stomach.

We report on the case of a 9-month-old Caucasian girl referred to our institution with a history of fever of unknown origin and wheezing, unresponsive to bronchodilator and anti-inflammatory therapy. Subsequent investigation led to a diagnosis of mediastinal lymphadenopathy caused by Mycobacterium avium-intracellulare (MAI). The infected lymph tissue infiltrated and obstructed the right bronchus and significantly compressed the left bronchus to the point of near closure. Given the high degree of morbidity and potential mortality from thoracic surgery in this patient, we treated her with a combination of anti-mycobacterial drugs (rifabutin, clarithromycin, ciprofloxacin, clofazimine, amikacin, ethambutol) and glucocorticoids to relieve airway compression. The endobronchial granulation tissue was resected by laser bronchoscopy. This combined approach led to eventual normalization of radiologic and endoscopic findings, and the anti-mycobacterial chemotherapy was discontinued 12 months after the first bronchoalveolar lavage culture was negative for MAI. The patient remains asymptomatic 1 year after completion of this course of therapy. We suggest that mediastinal lymphadenopathy with bronchial infiltration and extrinsic airway compression caused by MAI in otherwise healthy children can be successfully treated with aggressive chemotherapy, glucocorticoids, and laser bronchoscopy.

Rationale and Objectives. The purpose was to measure radiation exposure to the breasts during abdominal fluoroscopic examinations and evaluate the efficacy of breast shielding with a leaded vest. Materials and Methods. Sixty-six women underwent routine abdominal fluoroscopic examinations. During the examinations, one breast was covered with a leaded shield. Radiation doses to both breasts were measured with a thermoluminescent dosimeter. The amount of radiation at the skin of the shielded breast was then compared with that at the skin of the nonshielded breast. Results. Radiation exposure to the breasts varied substantially with the type of examination being performed and with the individual patient. The average radiation level at the skin of the unshielded breast was 119 mR (range, 0–6,320 mR), compared with 59.6 mR (range, 0–1,640 mR) at the shielded breast. The average reduction in radiation exposure was 50% with shielding. Conclusion. Although the average level of radiation exposure to the breast during abdominal fluoroscopic examinations is generally low, use of a leaded vest can further reduce radiation to the breast for different types of examinations.

We describe 2 children with prolonged fever of unknown origin and prominent skeletal pain who had multifocal bone disease caused by Bartonella infection. Initial radiologic studies, including plain films, radionuclide scintigraphy and computed tomography, yielded negative results. In both cases, magnetic resonance imaging revealed multiple enhancing bone marrow lesions consistent with clinical symptoms. Microbiologic diagnoses were established serologically.

The American Institute of Ultrasound in Medicine (AIUM) is a multidisciplinary association dedicated to advancing the safe and effective use of ultrasound in medicine through professional and public education, research, development of guidelines, and accreditation. To promote this mission, the AIUM is pleased to publish, in conjunction with the American College of Radiology (ACR), the Society for Pediatric Radiology (SPR), and the Society of Radiologists in Ultrasound (SRU), this AIUM Practice Guideline for the Performance of Native Renal Artery Duplex Sonography. We are indebted to the many volunteers who contributed their time, knowledge, and energy to bringing this document to completion. The AIUM represents the entire range of clinical and basic science interests in medical diagnostic ultrasound, and, with hundreds of volunteers, the AIUM has promoted the safe and effective use of ultrasound in clinical medicine for more than 50 years. This document and others like it will continue to advance this mission. Practice guidelines of the AIUM are intended to provide the medical ultrasound community with guidelines for the performance and recording of high-quality ultrasound examinations. The guidelines reflect what the AIUM considers the minimum criteria for a complete examination in each area but are not intended to establish a legal standard of care. AIUM-accredited practices are expected to generally follow the guidelines with recognition that deviations from these guidelines will be needed in some cases, depending on patient needs and available equipment. Practices are encouraged to go beyond the guidelines to provide additional service and information as needed.

Tick paralysis is an acute, progressive, and potentially fatal muscle paralysis secondary to a toxin secreted by a pregnant tick during a bite. Although tick bites can occur anywhere on the body, ticks are frequently overlooked on the scalp because of overlying hair. Children with acute neurologic symptoms frequently undergo MR scanning that may incidentally reveal the offending tick. Timely identification and removal of the tick leads to rapid recovery from tick paralysis. We report the MRI findings at 1.5 T of tick paralysis with an attached tick.

“Eighty percent of success is just showing up.”Woody AllenPediatric CT radiation dose optimization is a challenging process for pediatric-focused facilities and community hospitals alike. Ongoing experience and trial-and-error approaches to dose reduction in the large academic hospital setting may position these centers to help community hospitals who strive for CT quality improvement. In this pilot project, we describe our hands-on approach to develop a partnership between an academic medical center and a community hospital to develop a toolkit for implementing CT dose reduction. Our aims were to 1) assess the acceptability of an interactive educational program and electronic toolkit booklet, 2) conduct a limited test of the efficacy of the toolkit in promoting knowledge and readiness to change, and 3) assess the acceptability and practicality of a collaborative approach to implementing dose-reduction protocols in community hospitals. In partnering with the community hospital, we found that they had size specific radiation doses 2 to 3 times higher than those at our center. Survey results following a site visit with interactive educational presentations revealed an increase in knowledge, stronger opinions about the health risks of radiation from CT scans, and willingness and perceived ability to reduce pediatric CT doses.

Nephrolithiasis in Adults Low radiation dose, noncontrast-enhanced computed tomography (MDCT) with 2.5-mm image reconstruction in at least one plane is the test of choice for the patient with a suspected obstructing ureteral stone. In the absence of an available MDCT scanner, intravenous urography (IVU) or a combination of plain radiograph (KUB) and ultrasonography (US) should be performed (moderate evidence). Plain radiograph may be used to follow the descent of stones along the ureter (moderate evidence). For the pregnant patient when US is not diagnostic, MRI avoids ionizing radiation and may be useful with suspected nephroureterolithiasis (insufficient evidence).