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The aim of the study was to compare effects of a 100-kilovoltage (kVp) tin filtration (Sn100kVp) with Advanced Modeled Iterative Reconstruction (ADMIRE) protocol to an automated kVp selection and filtered back projection (FBP) protocol on radiation dose and image quality of in noncontrast-enhanced pediatric chest computed tomography (CT).This retrospective study included 55 children (12 ± 6 years) undergoing baseline imaging using automated kVp selection with FBP on a second-generation dual-source CT scanner and follow-up CT using Sn100kVp with ADMIRE on a third-generation dual-source CT scanner. The volume CT dose index, dose length product, size-specific dose estimate, and milliamperage were compared. Image quality was calculated using signal-to-noise ratio and subjectively evaluated by 2 radiologists.Mean volume CT dose index, dose length product, and size-specific dose estimate were lower for the Sn100kVp protocol with ADMIRE (0.83 ± 0.18 mGy, 21.9 ± 7.5 mGy × cm, 1.28 ± 0.24 mGy) compared with the automated kVp protocol with FBP (2.17 ± 1.10 mGy, 65.1 ± 41.1 mGy × cm, 3.25 ± 1.44 mGy, P0.001), whereas milliamperage was and subjective image quality were higher for Sn100kVp (P0.001).A Sn100kVp protocol with ADMIRE lowers dose while maintaining image quality in noncontrast-enhanced pediatric chest CT.

Widespread adoption of dual-energy computed tomography (DECT) requires evidence it does not cause higher radiation dose than conventional single-energy CT (SECT). While a few publications involving pediatric patients exist, most have focused on small cohorts. Hence, there is still a need for studies that ascertain what radiation doses are expected in larger populations that include representative ranges of patient sizes and ages. To compare radiation dose and image quality of DECT and SECT abdominopelvic examinations in children as a function of patient size. This retrospective study included 860 children (age range: 12.3±5.3 years) who underwent contrast-enhanced abdominopelvic exams on second-generation dual-source CT in a five-year period. Two groups, SECT and DECT, consisting of 430 children each, were matched by 5 effective diameters. Volume CT dose index (CTDIvol) and size-specific dose estimate (SSDE) were analyzed as a function of effective diameter. Objective image quality was compared between the groups. DECT SSDEs were lower across all effective patient diameters compared with SECT (mean: 8.5±1.8 mGv vs. 9.3±2.0 mGv, respectively, P≤0.001). DECT CTDIvol was lower compared to SECT (mean: 5.6±2.4 mGv vs. 6.1±2.7 mGv, respectively, P≤0.001) except in the smallest diameter group ( 0.05). In children, regardless of effective diameter, contrast-enhanced abdominopelvic DECT can be performed with a similar or lower dose and similar image quality compared with SECT examinations.

Methods to identify children with cystic fibrosis (CF) at risk for development of advanced liver disease are lacking. We aim to determine the association between liver stiffness measurement (LSM) by vibration-controlled transient elastography (VCTE) with research ultrasound (US) patterns and conventional hepatic markers as a potential means to follow liver disease progression in children with CF. ELASTIC (Longitudinal Assessment of Transient Elastography in CF) is a nested cohort of 141 patients, ages 7-21, enrolled in the Prediction by US of Risk of Hepatic Cirrhosis in CF (PUSH) Study. We studied the association between LSM with research-grade US patterns (normal [NL], heterogeneous [HTG], homogeneous [HMG], or nodular [NOD]) and conventional hepatic markers. In a subgroup (n = 79), the association between controlled attenuation parameter (CAP) and US pattern was explored. Among 133 subjects undergoing VCTE, NOD participants (n = 26) had a significantly higher median (interquartile range) LSM of 9.1 kPa (6.3, 15.8) versus NL (n = 72, 5.1 kPa [4.2, 7.0]; P

Dual-energy CT enables the simultaneous acquisition of CT images at two different x-ray energy spectra. By acquiring high- and low-energy spectral data, dual-energy CT can provide unique qualitative and quantitative information about tissue composition, allowing differentiation of multiple materials including iodinated contrast agents. The two dual-energy CT postprocessing techniques that best exploit the advantages of dual-energy CT in children are the material-decomposition images (which include virtual nonenhanced, iodine, perfused lung blood volume, lung vessel, automated bone removal, and renal stone characterization images) and virtual monoenergetic images. Clinical applications include assessment of the arterial system, lung perfusion, neoplasm, bowel diseases, renal calculi, tumor response to treatment, and metal implants. Of importance, the radiation exposure level of dual-energy CT is equivalent to or less than that of conventional single-energy CT. In this review, the authors discuss the basic principles of the dual-energy CT technologies and postprocessing techniques and review current clinical applications in the pediatric chest and abdomen.

To assess if a heterogeneous pattern on research liver ultrasound examination can identify children at risk for advanced cystic fibrosis (CF) liver disease.Planned 4-year interim analysis of a 9-year multicenter, case-controlled cohort study (Prospective Study of Ultrasound to Predict Hepatic Cirrhosis in CF). Children with pancreatic insufficient CF aged 3-12 years without known cirrhosis, Burkholderia species infection, or short bowel syndrome underwent a screening research ultrasound examination. Participants with a heterogeneous liver ultrasound pattern were matched (by age, Pseudomonas infection status, and center) 1:2 with participants with a normal pattern. Clinical status and laboratory data were obtained annually and research ultrasound examinations biannually. The primary end point was the development of a nodular research ultrasound pattern, a surrogate for advanced CF liver disease.There were 722 participants who underwent screening research ultrasound examination, of which 65 were heterogeneous liver ultrasound pattern and 592 normal liver ultrasound pattern. The final cohort included 55 participants with a heterogeneous liver ultrasound pattern and 116 participants with a normal liver ultrasound pattern. All participants with at least 1 follow-up research ultrasound were included. There were no differences in age or sex between groups at entry. Alanine aminotransferase (42 ± 22 U/L vs 32 ± 19 U/L; P = .0033), gamma glutamyl transpeptidase (36 ± 34 U/L vs 15 ± 8 U/L; P .001), and aspartate aminotransferase to platelet ratio index (0.7 ± 0.5 vs 0.4 ± 0.2; P .0001) were higher in participants with a heterogeneous liver ultrasound pattern compared with participants with a normal liver ultrasound pattern. Participants with a heterogeneous liver ultrasound pattern had a 9.1-fold increased incidence (95% CI, 2.7-30.8; P = .0004) of nodular pattern vs a normal liver ultrasound pattern (23% in heterogeneous liver ultrasound pattern vs 2.6% in normal liver ultrasound pattern).Research liver ultrasound examinations can identify children with CF at increased risk for developing advanced CF liver disease.

Imaging is essential in successfully executing radiation therapy (RT) in oncology clinical trials. As technically sophisticated diagnostic imaging and RT were incorporated into trials, quality assurance in the National Clinical Trials Network groups entered a new era promoting image acquisition and review. Most trials involving RT require pre- and post-therapy imaging for target validation and outcome assessment. The increasing real-time (before and during therapy) imaging and RT object reviews are to ensure compliance with trial objectives. Objects easily transmit digitally for review from anywhere in the world. Physician interpretation of imaging and image application to RT treatment plans is essential for optimal trial execution. Imaging and RT data sets are used to credential RT sites to confirm investigator and institutional ability to meet trial target volume delineation and delivery requirements. Real-time imaging and RT object reviews can be performed multiple times during a trial to assess response to therapy and application of RT objects. This process has matured into an effective data management mechanism. When necessary, site and study investigators review objects together through web media technologies to ensure the patient is enrolled on the appropriate trial and the intended RT is planned and executed in a trial-compliant manner. Real-time imaging review makes sure: (1) the patient is entered and eligible for the trial, (2) the patient meets trial-specific adaptive therapy requirements, if applicable, and (3) the intended RT is according to trial guidelines. This review ensures the study population is uniform and the results are believable and can be applied to clinical practice.

This is the third of a series of 4 white papers that represent Expert Consensus Documents developed by the Society of Computed Body Tomography and Magnetic Resonance through its Task Force on dual-energy computed tomography. This paper, part 3, describes computed tomography angiography and thoracic, cardiac, vascular, and musculoskeletal clinical applications. At the end of the discussion of each application category (vascular, cardiac, pulmonary, and musculoskeletal), we present our consensus opinions on the current clinical utility of the application and opportunities for further research.

This is the fourth of a series of 4 white papers that represent expert consensus documents developed by the Society of Computed Body Tomography and Magnetic Resonance through its task force on dual-energy computed tomography. This article, part 4, discusses DECT for abdominal and pelvic applications and, at the end of each, will offer our consensus opinions on the current clinical utility of the application and opportunities for further research.

Historically, administration of dacarbazine to sarcoma patients was limited by frequent treat-ment-related nausea/vomiting and neutropenia. These toxicities are now largely preventable with contemporary antiemetics and growth factor support. In this single-arm, phase II study, dacarbazine 850 mg/m2 was given on day 1 of each 3-week cycle until disease progression or intolerance with prophylactic serotonin-3 receptor, neurokinin-1 antagonists, corticosteroids, and pegfilgrastim. Coprimary endpoints included clinical benefit rate (CBR), and any grade of nausea/vomiting and/or grade 3–4 neutropenia. With a sample size of 80 patients, >24 patients with clinical benefit would indicate that the CBR exceeds the historical (

Technical advances in CT have enabled implementation of dual-energy CT into routine clinical practice. By acquiring images at two different energy spectra, dual-energy CT enables material decomposition, allowing generation of material- and energy-specific images. Material-specific images include virtual nonenhanced images and iodine-specific images (iodine maps). Energy-specific images include virtual monoenergetic images. The reconstructed images can provide unique qualitative and quantitative information about tissue composition and contrast media distribution. In thoracic oncologic imaging, dual-energy CT provides advantages in characterization of thoracic malignancies and lung nodules, determination of extent of disease, and assessment of response to therapy. An especially important feature in children is that dual-energy CT does not come at a higher radiation exposure. Keywords: CT, CT-Quantitative, Lung, Mediastinum, Neoplasms-Primary, Pediatrics, Thorax, Treatment Effects © RSNA, 2021

Summary Background Angiogenesis is a hallmark of head and neck squamous cell carcinoma (HNSCC), and a mechanism of resistance to EGFR inhibition. We investigated the safety and potential activity of pazopanib, an angiogenesis inhibitor, plus cetuximab, an EGFR inhibitor, in patients with recurrent or metastatic HNSCC. Methods We did an open-label, single-centre, dose-escalation phase 1b trial using a standard 3 + 3 design, followed by an expansion cohort phase. Eligible participants were patients with histologically or cytologically confirmed recurrent or metastatic HNSCC, aged at least 18 years, had measurable disease as per Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1, and an Eastern Cooperative Oncology Group performance status of 0–1. During dose escalation, pazopanib oral suspension was administered daily in 8-week cycles at doses of 200 mg/day, 400 mg/day, 600 mg/day, or 800 mg/day, with cetuximab given intravenously once per week (400 mg/m2 first dose and 250 mg/m2 in consecutive cycles). The primary endpoint was to determine the maximum tolerated dose or recommended phase 2 dose of pazopanib in combination with cetuximab. Analyses were done per protocol. This trial is registered with ClinicalTrials.gov, number NCT01716416, and it is ongoing but closed to accrual. Findings Between June 5, 2013, and April 4, 2017, we enrolled 22 patients into the phase 1b, dose-escalation phase of the trial. A maximum tolerated dose of pazopanib in combination with cetuximab was not reached. Single dose-limiting toxic events (all grade 3) during dose escalation occurred with pazopanib 400 mg/day (neutropenia with infection), 600 mg/day (proteinuria), and 800 mg/day (fatigue). The established recommended phase 2 dose for the combination was 800 mg/day of pazopanib during cycles of 8 weeks each, plus cetuximab 400 mg/m2 on day 1 of cycle 1, then cetuximab 250 mg/m2 weekly. A further nine patients were enrolled into the expansion cohort and treated with the established recommended phase 2 dose. The most common (grade 3–4) adverse events for all patients were hypertension (ten [32%] of 31), lymphocyte count decrease (seven [23%]), and dysphagia (seven [23%]). There were no treatment-related deaths. 11 (35%; 95% CI 19·2–54·6) of 31 patients achieved an overall response, as assessed by the investigator; two (6%) had a complete response and nine (29%) a partial response. Tumour responses were also observed in six (55%) of 11 patients with platinum-naive and cetuximab-naive disease, three (25%) of 12 patients with cetuximab-resistant disease, and five (28%) of 18 patients with platinum-resistant disease. Interpretation Pazopanib oral suspension at a dose of 800 mg/day was feasible to administer in combination with standard weekly cetuximab for patients with recurrent or metastatic HNSCC. Encouraging preliminary antitumour activity was observed with this combination therapy and warrants further validation in randomised trials. Funding GlaxoSmithKline and Novartis.

Purpose Addition of imatinib to intensive chemotherapy improved survival for children and young adults with Philadelphia chromosome–positive acute lymphoblastic leukemia. Compared with imatinib, dasatinib has increased potency, CNS penetration, and activity against imatinib-resistant clones. Patients and Methods Children’s Oncology Group (COG) trial AALL0622 (Bristol Myers Squibb trial CA180-204) tested safety and feasibility of adding dasatinib to intensive chemotherapy starting at induction day 15 in patients with newly diagnosed Philadelphia chromosome–positive acute lymphoblastic leukemia age 1 to 30 years. Allogeneic hematopoietic stem-cell transplantation (HSCT) was recommended for patients at high risk based on slow response and for those with a matched family donor regardless of response after at least 11 weeks of therapy. Patients at standard risk based on rapid response received chemotherapy plus dasatinib for an additional 120 weeks. Patients with overt CNS leukemia received cranial irradiation. Results Sixty eligible patients were enrolled. Five-year overall (OS) and event-free survival rates (± standard deviations [SD]) were 86% ± 5% and 60% ± 7% overall, 87% ± 5% and 61% ± 7% for standard-risk patients (n = 48; 19% underwent HSCT), and 89% ± 13% and 67% ± 19% for high-risk patients (n = 9; 89% underwent HSCT), respectively. Five-year cumulative incidence (± SD) of CNS relapse was 15% ± 6%. Outcomes (± SDs) were similar to those in COG AALL0031, which used the same chemotherapy with continuous imatinib: 5-year OS of 81% ± 6% versus 86% ± 5% ( P = .63) and 5-year disease-free survival of 68% ± 7% versus 60% ± 7% ( P = 0.31) for AALL0031 versus AALL0622, respectively. IKZF1 deletions, present in 56% of tested patients, were associated with significantly inferior OS and event-free survival overall and in standard-risk patients. Conclusion Dasatinib was well tolerated with chemotherapy and provided outcomes similar to those with imatinib in COG AALL0031, where all patients received cranial irradiation. Our results support limiting HSCT to slow responders and suggest a potential role for transplantation in rapid responders with IKZF1 deletions.

This is the second of a series of 4 white papers that represent Expert Consensus Documents developed by the Society of Computed Body Tomography and Magnetic Resonance through its task force on dual-energy computed tomography. This paper, part 2, addresses radiation dose and iodine sensitivity in dual-energy computed tomography.

This is the first of a series of 4 white papers that represent Expert Consensus Documents developed by the Society of Computed Body Tomography and Magnetic Resonance through its task force on dual-energy computed tomography (DECT). This article, part 1, describes the fundamentals of the physical basis for DECT and the technology of DECT and proposes uniform nomenclature to account for differences in proprietary terms among manufacturers.

This is an expert consensus document created to provide information about the current use of cardiovascular computed tomography (CT) in patients of all ages with proven or suspected congenital heart disease (CHD). The discussion and recommendations are based on available literature and the judgment of a diverse group of subspecialists with extensive experience in the use of CT imaging in CHD. The field of CHD CT imaging is evolving rapidly with the availability of new scanner technology. In addition, the prevalence of palliated CHD has increased with marked improvements in patient survival. We believe it is important to review the clinical indications, strengths, limitations, and risks of cardiovascular CT in this patient population. This is the first of two complementary documents. It will concentrate on the disease entities and circumstances in which CT may be used. The second document will focus on recommendations for the technical performance of cardiovascular CT in patients with CHD. Successful cardiovascular CT imaging of CHD requires an in depth understanding of the core teaching elements of both cardiology and radiology. The ability to perform and interpret high quality congenital cardiovascular CT in a clinical context requires focused time and effort regardless of the previous background of the cardiac imager. This is reflected by a writing committee that consists of pediatric and adult radiologists and cardiologists, all whom have extensive experience in performing CT in this patient population. Cardiovascular CT is complementary to other imaging modalities and its optimal use will be in centers where all diagnostic modalities are available. The choice of modality for an individual patient should be determined by age, diagnosis, clinical condition, clinical question and patient preference.(1-4) Use of CT in CHD should be reserved for situations in which it is expected to provide unique diagnostic information for the individual patient or clinical indication, and/or less risk than other modalities. This multi-disciplinary document is intended to guide the optimal selection of CHD patients for cardiovascular CT. The goals of this document apply to both pediatric and adult CHD patients and are to.

This article compares the technical factors-in particular, tube current and voltage-and the resultant exposure to radiation associated with CT examinations performed at a children's hospital and at more general community hospital emergency departments (EDs).CT scans obtained at community hospital EDs were retrospectively reviewed and compared with CT scans obtained at a children's hospital, to assess differences in kilovoltage, tube current, and volume CT dose index (CTDIvol) used. The number of scans obtained during the contrast-enhanced phase was also assessed. Parametric and nonparametric statistical analyses were used to test differences.A total of 233 body CT examinations were performed at community hospitals, and 287 were performed at a children's hospital. At both types of hospital, the median patient age was 12 years (p = 0.66). Of the body CT scans obtained at community hospitals that focused on the care of adult patients, 194 of 233 (83%) used a tube voltage of 120 kVp, 29 of 233 (12%) used 100 kVp, and two of 233 (1%) used 80 kVp. Of the body CT scans obtained at the children's hospital, 121 of 287 (42%) used a tube voltage of 120 kVp, 129 of 287 (45%) used 100 kVp, and 36 of 287 (13%) used 80 kVp. The median tube current was also lower at the children's hospital (110 vs 125 mA) (p0.001). At the community hospitals, 11 of 233 studies were multiphasic, whereas at the children's hospital, there were no multiphasic studies. For all CT types, the median CTDIvol was 4.9 mGy (range, 2.5-8.2 mGy) at the children's hospital and 8.6 mGy (range, 6.0-14.4 mGy) at the community hospitals (p0.001).The results of this study suggest that a large proportion of children who undergo CT at community hospitals receive relatively higher radiation doses than children who undergo CT at children's hospitals. This finding is related to the higher tube settings (in particular, kilovoltage) used at community hospitals.

Background: Clubfoot treatment commonly fails and often results in impaired quality of life. An understanding of the soft-tissue abnormalities associated with both treatment-responsive and treatment-resistant clubfoot is important to improving the diagnosis of clubfoot, the prognosis for patients, and treatment. Methods: Twenty patients with clubfoot treated with the Ponseti method were recruited for magnetic resonance imaging (MRI) of their lower extremities. Among these were seven patients (six unilateral cases) with treatment-responsive clubfoot and thirteen patients (five unilateral cases) with treatment-resistant clubfoot. Demographic information and physical examination findings were recorded. A descriptive analysis of the soft-tissue abnormalities was performed for both patient cohorts. For the patients with unilateral clubfoot, we calculated the percentage difference in cross-sectional area between the affected limb and the unaffected limb in terms of muscle, subcutaneous fat, intracompartment fat, and total area. With use of the Wilcoxon signed-rank test, we compared inter-leg differences in cross-sectional areas and the intracompartment adiposity index (IAI) between treatment-responsive and treatment-resistant groups. The IAI characterizes the cross-sectional area of fat within a muscle compartment. Results: Extensive soft-tissue abnormalities were more present in patients with treatment-resistant clubfoot than in patients with treatment-responsive clubfoot. Treatment-resistant clubfoot abnormalities included excess epimysial fat and intramuscular fat replacement as well as unique patterns of hypoplasia in specific muscle groups that were present within a subset of patients. Among the unilateral cases, treatment-resistant clubfoot was associated with a significantly greater difference in muscle area between the affected and unaffected limb (−47.8%) compared with treatment-responsive clubfoot (−26.6%) (p = 0.02), a significantly greater difference in intracompartment fat area between the affected and unaffected limb (402.6%) compared with treatment-responsive clubfoot (9%) (p = 0.01), and a corresponding higher inter-leg IAI ratio (8.7) compared with treatment-responsive clubfoot (1.5) (p = 0.01). Conclusions: MRI demonstrated a range of soft-tissue abnormalities in patients, including unique patterns of specific muscle-compartment aplasia/hypoplasia that were present in patients with treatment-resistant clubfoot and not present in patients with treatment-responsive clubfoot. Correlations between MRI, physical examination, and treatment responsiveness may aid in the development of a prognostic classification system for clubfoot. Level of Evidence: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Computed tomography (CT), the standard method to assess tumor response to cetuximab in incurable squamous cell carcinoma of the head and neck (SCCHN), performs poorly as judged by the disparity between high disease control rate (46%) and short time to progression (TTP) (70 days). F-18 fluorodeoxyglucose positron emission tomography (FDG-PET)/CT is an alternative method to assess tumor response. The primary objective of this prospective trial was to evaluate the metabolic response of target lesions, assessed as the change in maximum standardized uptake value (SUVmax) on FDG-PET/CT before and after 8 weeks (cycle 1) of cetuximab. Secondary objectives were to compare tumor response by CT (RECIST 1.0) and FDG-PET/CT (EORTC criteria) following cycle 1, and determine TTP with continued cetuximab administration in patients with disease control by CT after cycle 1 but stratified for disease control or progression by FDG-PET/CT. Among 27 patients, the mean percent change of SUVmax of target lesions after cycle 1 was −21% (range: +72% to −81%); by FDG-PET/CT, partial response (PR)/stable disease (SD) occurred in 15 patients (56%) and progression in 12 (44%), whereas by CT, PR/SD occurred in 20 (74%) and progression in 7 (26%). FDG-PET/CT and CT assessments were discordant in 14 patients (P = 0.0029) and had low agreement (κ = 0.30; 95% confidence interval [CI]: 0.12, 0.48). With disease control by CT after cycle 1, median TTP was 166 days (CI: 86, 217) if the FDG-PET/CT showed disease control and 105 days (CI: 66, 159) if the FDG-PET/CT showed progression (P < 0.0001). Median TTP of the seven patients whose post cycle 1 CT showed progression compared to the 12 whose FDG-PET/CT showed progression were similar (53 [CI: 49, 56] vs. 61 [CI: 50, 105] days, respectively). FDG-PET/CT may be better than CT in assessing benefit of cetuximab in incurable SCCHN.

Purpose To compare diffusion-weighted magnetic resonance imaging (DW-MRI) with positron emission tomography/computed tomography (PET/CT) for staging and evaluating treatment response in patients with diffuse large B-cell lymphoma (DLBCL).

A 13-year-old girl was incidentally found to have a partially calcified anterior mediastinal mass during the work-up for a left humeral lesion. The resected specimen demonstrated a lymphocyte predominant World Health Organization type B1 thymoma with nodules of metaplastic bone consistent with osseous metaplasia. In addition, she had multiple osteochondromas, a periosteal chondroma of the humerus, a metaplastic osseous pseudotumor of the thigh, and other benign-appearing sclerotic foci, all manifestations of what is likely an autosomal dominant disorder.

The purpose of this study was to compare the effects of combined automated tube voltage selection and automated tube current modulation on radiation dose and image quality in small-sized phantoms undergoing computed tomography angiography (CTA) with the use of automated current modulation alone.Three semianthropomorphic phantoms, corresponding to a neonate, a small child, and a small adult, underwent simulated abdominal CTA using an automated tube voltage selection technology, which simultaneously optimizes kilovoltage (in kilovolt [peak]) and tube-current/milliamperage (in milliampere-second) on the basis of the patient topogram and clinical task. The phantoms were scanned with 2 protocols: protocol A, using the combination of automated kilovoltage and milliamperage, and protocol B, using only automated milliamperage with the standard 120 kV(p). Radiation doses were measured for each phantom, and the measurements were then used to estimate volume computed tomography dose index. Image noise and iodine contrast, contrast-to-noise ratio, and the relative dose factor were assessed. Differences were tested using paired t tests, and percentage differences for various technical factors and the phantom sizes were calculated.The computed tomography dose index was significantly lower in protocol A (mean, 3.3 mGy) compared with that in protocol B (mean, 7.7 mGy), representing a 56.0% dose reduction (P = 0.01). In protocol A, tube potential dropped from 120 to 70 kV(p) in the small and medium phantoms and to 80 kV(p) in the large phantom. For each phantom size, image noise and iodine contrast increased significantly in protocol A relative to those in protocol B (P = 0.03 and P0.01, respectively). Corresponding contrast-to-noise ratio values increased by 9.1% in protocol A relative to those in protocol B (P = 0.04). The relative dose factor values for protocol A relative to those for protocol B were 31%, 36%, and 44% for the small, medium, and large phantoms, respectively.Combined use of automated kilovoltage selection and automated tube current modulation is more effective for reducing radiation dose and maintaining image quality during simulated pediatric CTA than is automated tube current modulation in isolation.

To compare whole-body magnetic resonance (MR) imaging with conventional imaging for detection of distant metastases in pediatric patients with common malignant tumors.This institutional review board-approved, HIPAA-compliant, multicenter prospective cohort study included 188 patients (109 male, 79 female; mean age, 10.2 years; range,1 to 21 years) with newly diagnosed lymphoma, neuroblastoma, or soft-tissue sarcoma. Informed consent was obtained and all patients underwent noncontrast material-enhanced whole-body MR imaging and standard-practice conventional imaging. All images were reviewed centrally by 10 pairs of readers. An independent panel verified the presence or absence of distant metastases. Detection of metastasis with whole-body MR and conventional imaging was quantified by using the area under the receiver operating characteristic curve (AUC). The effects of tumor subtype, patient age, and distant skeletal and pulmonary disease on diagnostic accuracy were also analyzed.Of the 134 eligible patients, 66 (33 positive and 33 negative for metastasis) were selected for image review and analysis. Whole-body MR imaging did not meet the noninferiority criterion for accuracy when compared with conventional imaging for detection of metastasis (difference between average AUCs was -0.03 [95% confidence interval: -0.10, 0.04]); however, the average AUC for solid tumors was significantly higher than that for lymphomas (P = .006). More skeletal metastases were detected by using whole-body MR imaging than by using conventional imaging (P = .03), but fewer lung metastases were detected (P.001). Patient age did not affect accuracy.The noninferior accuracy for diagnosis of distant metastasis in patients with common pediatric tumors was not established for the use of whole-body MR imaging compared with conventional methods. However, improved accuracy was seen with whole-body MR imaging in patients with nonlymphomatous tumors.

OBJECTIVE. The purpose of this study was to assess the effects of dual-energy CT (DECT) on radiation exposure and image quality in pediatric body CT. MATERIALS AND METHODS. This retrospective study included 79 children (median age, 10.1 years; range, 12 days–18 years) who underwent thoracic or abdominal-pelvic CT or CT angiography with dual-energy technique between October 2014 and March 2015. The delivered volume CT dose index (CTDIvol) from DECT was recorded and compared with the estimated CTDIvol had the patient undergone scanning with a standard single-energy CT (SECT) protocol. Size-specific dose estimates were calculated for both DECT and SECT. Image quality was subjectively scored (scale, 1–4). For 16 of 79 patients who underwent both DECT and SECT, image contrast and noise were measured and contrast-to-noise ratio calculated. Parametric and nonparametric testing of independent and paired samples was performed. RESULTS. For all 79 studies, actual median CTDIvol and size-specific dose estimate were ...

We present a case of a renal rhabdoid tumor in a 2-month-old girl. Rhabdoid tumors are rare primary renal tumors in children, but they have characteristic features--medullary sinus invasion and subcapsular fluid collections--which enable a specific diagnosis. The classic imaging characteristics of this tumor compared to other more common primary pediatric renal tumors will be reviewed.

The National Lung Screening Trial (NLST) is a randomized multicenter study comparing low-dose helical computed tomography (CT) with chest radiography in the screening of older current and former heavy smokers for early detection of lung cancer, which is the leading cause of cancer-related death in the United States. Five-year survival rates approach 70% with surgical resection of stage IA disease; however, more than 75% of individuals have incurable locally advanced or metastatic disease, the latter having a 5-year survival of less than 5%. It is plausible that treatment should be more effective and the likelihood of death decreased if asymptomatic lung cancer is detected through screening early enough in its preclinical phase. For these reasons, there is intense interest and intuitive appeal in lung cancer screening with low-dose CT. The use of survival as the determinant of screening effectiveness is, however, confounded by the well-described biases of lead time, length, and overdiagnosis. Despite previous attempts, no test has been shown to reduce lung cancer mortality, an endpoint that circumvents screening biases and provides a definitive measure of benefit when assessed in a randomized controlled trial that enables comparison of mortality rates between screened individuals and a control group that does not undergo the screening intervention of interest. The NLST is such a trial. The rationale for and design of the NLST are presented.

Cardiac computed tomography (CT) is a rapidly advancing technology that complements echocardiography in the imaging evaluation of congenital heart disease. CT can play an important role in diagnosis and follow-up via assessment of anatomic features and postoperative complications. An understanding of the pathophysiology and imaging characteristics of various congenital heart lesions is essential for effective implementation and accurate interpretation of the cardiac CT examination.

A chronic state of impaired venous drainage from the central nervous system, termed chronic cerebrospinal venous insufficiency (CCSVI), is claimed to be a pathologic phenomenon exclusively seen in multiple sclerosis (MS). This has invigorated the causal debate of MS and generated immense interest in the patient and scientific communities. A potential shift in the treatment paradigm of MS involving endovascular balloon angioplasty or venous stent placement has been proposed as well as conducted in small patient series. In some cases, it may have resulted in serious injury. In this Point of View, we discuss the recent investigations that led to the description of CCSVI as well as the conceptual and technical shortcomings that challenge the potential relationship of this phenomenon to MS. The need for conducting carefully designed and rigorously controlled studies to investigate CCVSI has been recognized by the scientific bodies engaged in MS research. Several scientific endeavors examining the presence of CCSVI in MS are being undertaken. At present, invasive and potentially dangerous endovascular procedures as therapy for patients with MS should be discouraged until such studies have been completed, analyzed, and debated in the scientific arena.

Fanconi's anemia, type A presenting as VACTERL association with atresia right external auditory canal

Cardiac magnetic resonance is a powerful, rapidly advancing technology that complements other imaging modalities in the noninvasive evaluation of congenital heart disease. Magnetic resonance plays an important role in diagnosis and follow-up by assessing anatomic features, functional effects, and postoperative complications. An understanding of the pathophysiology and imaging characteristics of various congenital heart lesions is essential for effective implementation and accurate interpretation of the cardiac magnetic resonance examination.

Neuroblastoma is one of the most common non-central nervous system solid tumors in children. Imaging plays a role in the evaluation of the primary tumor and regional and distant disease. This article reviews the biologic, clinical, and MR imaging features of this tumor.

Wilms' tumor is the most common solid renal tumor in children. Imaging plays a crucial role in the evaluation of the primary tumor and regional and metastatic disease. This article reviews the biologic, clinical, and MR imaging features of this tumor and other renal tumors that can mimic Wilms' tumor.

The introduction of the graded-compression sonographic technique and continued advances in ultrasound technology have increased the use of sonography in evaluating the child who has a suspected surgical abdomen. Sonography is used to characterize the nature of the many conditions associated with acute abdominal symptoms and signs and to differentiate between those requiring urgent surgical intervention and those that do not. This article reviews the sonographic evaluation of common important surgical conditions of the abdomen in children. Indications for performing sonography, sonographic features of common lesions, and the sonographic techniques best suited to making a diagnosis are addressed.

Advances in multidetector computed tomography (CT) technology have revolutionized thoracic imaging in children. Faster scanning times, increased anatomic coverage, and high quality reconstructions have enabled CT to become a valuable tool in the evaluation of thoracic diseases. CT images are helpful in detecting, characterizing and determining the extent of abnormalities in the lungs, mediastinum, vasculature, chest wall and peridiaphragmatic regions. The information provided by these techniques can directly affect the treatment or aid in determining the prognosis of a patient.

The aim of this study was to determine whether the use of multidetector computed tomography (MDCT) is associated with decreased sedation, frequency of motion artefacts and conventional angiograms compared with single-detector CT (SDCT).CT examinations performed in young children between January 1993 and June 2005 were reviewed retrospectively. Prior to September 2000, SDCT was used; after that period, MDCT was used. The examinations obtained during these two periods were compared for the frequency of sedation, motion artefacts, and conventional angiograms. Statistical comparison between the two groups was determined by using the chi(2) test.A total of 126 infants and children younger than 6 years of age underwent 134 CT examinations. Eighty-eight were obtained with a SDCT (65%) (group 1) and 46 with a MDCT (35%) (group 2). Sedation was required in 31/88 (35%) CT examinations in group 1 and in 6/46 (13%) in group 2. Conventional angiography was performed in 20/88 (22%) cases in group 1 and in 6/46 (13%) in group 2. Motion artefacts were present in 8/88 (9%) CT examinations in group 1 and in 4/46 (8%) in group 2. There was significant statistical difference with regard to sedation and angiography rates between the two groups (p0.001) whereas there was no significant difference with regard to motion artefacts (p1).MDCT can reduce the need for sedation and conventional angiography in children after liver transplantation. There is no effect on patient motion artefacts.

Advances in CT technology are having profound impact on imaging children and have made CT angiography possible even in neonates. Even with the tiny anatomy of neonates, small volumes of contrast material, and small venous access catheters, successful CT angiography can be performed with attention to detail. Meticulous attention to patient preparation, the proper selection of technical factors, and optimal delivery of contrast material are crucial. Data post-processing and the creation of 3-D reconstructions are also essential in establishing a correct diagnosis. The applications of CT angiography are different in children than in adults and most applications in children involve assessment of congenital and postoperative vascular and cardiac diseases. The use of CT angiography offers the opportunity to eliminate the long periods of sedation associated with MR and reduce the radiation exposure associated with conventional angiography. Generally, the benefits of CT angiography in children outweigh the risk, namely that of radiation exposure. However, care must still be taken to minimize the radiation exposure.

Background: MRI is an effective tool in evaluating bone marrow metastases. However, no study has defined which MRI sequences or image characteristics best correlate with bone-marrow metastases in neuroblastoma. Objective: To identify and refine MRI criteria and sequence selection for the diagnosis of bone-marrow metastases in children with neuroblastoma. Materials and methods: Ninety-one children (mean age: 3.2 years; standard deviation: 2.8 years) enrolled in the RDOG IV study participated in our study. Forty-five children had bone metastases determined by bone-marrow aspiration or biopsy (n=4), radionuclide imaging (n=2), or both (n=39). Spine lesions were characterized using coronal T1-weighted (T1W) sagittal short tau inversion recovery (STIR) and coronal gadolinium-enhanced T1-weighted (GAD) MR sequences. Contingency table analysis was performed to determine which MRI sequences and characteristics were associated with metastases. The MRI criteria for metastatic disease were then developed for each imaging sequence. The sensitivity, specificity, predictive values, and accuracy of these criteria were determined for the whole group, children younger than 12 months old, and children 12 months and older. Results: The MR characteristics that had significant (P ≤ 0.05) associations with metastases were homogeneous low T1-signal intensity, homogeneous high STIR-signal intensity, and heterogeneous pattern on T1, STIR, or GAD. Homogeneous low T1-signal had the highest sensitivity (88%), but a specificity of 62% for detecting metastases. A heterogeneous pattern on GAD was highly specific (97%), but relatively insensitive (65%) for detecting metastases. These MR characteristics were most accurate in children 12 months and older. Conclusion: The combination of non-contrast-enhanced T1W and GAD sequences can be used to determine the presence of spinal metastases in children with neuroblastoma, particularly those children who are 1 year and older.

Tumors of the renal medulla cover a wide spectrum, with characteristic histomorphology and variable biologic profiles. Renal medullary tumors can be categorized into benign and malignant neoplasms based on histologic features and clinico-biologic behavior. They can be further classified into pediatric and adult tumors based on the patient age group. When small, renal medullary tumors may be differentiated from the more common renal adenocarcinomas by their central location and certain demographic characteristics. Although most large malignant medullary tumors demonstrate imaging findings that are indistinguishable from those of other renal malignancies, some tumors demonstrate imaging findings that may suggest a specific diagnosis.

Klippel Feil syndrome with occipital encephalocele, duodenal web, left pelvic kidney, ASD, anorectal malformation fetal and postnatal imaging

To evaluate effects of varying tube current and voltage on radiation dose, image noise, and image contrast with different phantom sizes and shapes.Four round lucite phantoms with 8-32-cm diameters were scanned with multi-detector row computed tomography (CT) and 80-120 kVp. Radiation dose was based on CT dose index, image noise, and iodine contrast and measured with constant and variable tube currents that were age appropriate for each tube voltage. Radiation dose and image noise and contrast were compared in round and oval 24-cm phantoms. For various combinations of technical factors and phantom sizes and shapes, percentage differences were calculated for radiation dose and image noise and contrast. Associations between tube voltage and radiation dose, image noise, and image contrast in round and oval phantoms were determined by fitting second-degree polynomials to data. Differences in radiation dose and image noise and contrast, which were attributable to differences in tube voltage, were tested with paired t tests.With 165-mAs tube current, radiation doses with 140- and 80-kVp tube voltages were 103% ([41.9 mGy - 20.6 mGy]/20.6 mGy) and 58% ([10.2 mGy - 4.2 mGy]/10.1 mGy) higher in the 8-cm phantom than in the 32-cm phantom. When tube current was adapted for phantom size, radiation dose at 80 kVp in the 8-cm phantom was reduced by 82% ([10.1 mGy - 1.8 mGy]/10.1 mGy). In the 8-cm phantom, tube voltage was decreased from 120 to 80 kVp and tube current remained at 165 mAs, resulting in a 68% noise increase ([3.1 HU - 1.8 HU]/1.8 HU). With variable tube current, 80-kVp tube voltage in the 8-cm phantom led to a 138% noise increase ([7.3 HU - 3.1 HU]/3.1 HU). With reduced tube voltage, image contrast increased. In the 8-cm phantom, with a constant 165-mAs tube current and a decrease in tube voltage from 120 to 80 kVp, there was a 35% ([333 HU - 217 HU]/333 HU) increase in contrast. No difference was noted in radiation dose or noise between round and oval phantoms (P = .604 and P = .06, respectively), but a small statistically significant difference (1%) in contrast attenuation was demonstrated (P = .025).Reduced tube voltage for pediatric contrast material-enhanced CT reduces radiation dose and maintains image contrast. Image noise increases, but the effect is minimal in smaller phantoms. An additional reduction in tube current further reduces radiation dose.

To describe the chest radiographic appearance of the Amplatzer septal occluder (ASO) (AGA Medical Corporation, Golden Valley, Minn) for atrial septal defects (ASDs) in pediatric patients.Two radiologists independently reviewed frontal and lateral chest radiographs obtained in young patients 24 hours after transcatheter ASD closure with the ASO. The appearance (flat disks or dots) and location of the ASO were recorded. The location was related to that of a thoracic vertebral body on frontal and lateral chest radiographs and to a line drawn between the anterior margin of the right hilum and the posterior margin of the inferior vena cava (hilar-caval line) on lateral radiographs; this line corresponded to the expected position of the interatrial septum. The relationship between ASO appearance and patient age was assessed with logistic regression and cumulative probability plots.Sixty-eight pediatric patients (age range, 1 month to 18 years; mean age, 4.2 years; 24 boys and 44 girls) were included. On frontal radiographs, the ASO center projected between T7 and T9, either to the right of or over the spinous processes of the vertebral body. On lateral radiographs, the ASO projected over (n = 66) or anterior to (n = 2) the hilar-caval line. On frontal radiographs, it appeared as one or two flat disks (n = 61) or as two metallic dots (n = 7). On lateral radiographs, it appeared as two flat disks (n = 54) or as two metallic dots (n = 14). The relationship between increasing patient age and the metallic dot appearance on frontal and lateral radiographs and on the combination of frontal and lateral radiographs was highly significant in each case (P.001, likelihood ratio chi(2) test), with r(2) values of 0.35, 0.20, and 0.28, respectively. ASDs were successfully occluded with the ASO in all patients except one, in whom trivial shunting was seen at 12-month follow-up.The ASO in pediatric patients has a characteristic radiographic appearance when properly positioned.

Extralobar pulmonary sequestration (ELS) and congenital cystic adenomatoid malformation have been reported to coexist in several variations. This suggests a common embryologic origin. A 6-month-old boy presented with a history of recurrent pneumonias. The patient was diagnosed with a right lower lobe congenital cystic adenomatoid malformation (CCAM) and a left lower lobe ELS/CCAM. The diagnosis was made with the aid of a multidetector computed tomography (CT). Three-dimensional CT reconstruction showed the presence of a right lower lobe CCAM, a left lower ELS with an aberrant arterial supply from the celiac axis, and possible venous drainage into the right CCAM. The patient underwent a right thoracotomy. Intraoperatively, the lesions were discovered to be connected by a band of tissue. The right lower lobe CCAM and the left ELS were removed from the right chest. Histologic analysis confirmed the presence of a CCAM within the right lower lobe. The ELS had involvement of a type II CCAM within the sequestration. The connection between the right CCAM and left ELS/CCAM showed an anomalous conducting airway, anomalous vein, and anomalous artery connecting the 2 lesions. The authors present the first case of a CCAM connected to an ELS/CCAM in the contralateral hemithorax. The unique anatomic configuration of these lesions suggests a common embryologic origin of ELS and CCAM.