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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.

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.

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 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.

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.

Obtaining information on transplanted lung microstructure is an important part of the current care for monitoring transplant recipients. However, until now this information was only available from invasive lung biopsy. The objective of this study was to evaluate the use of an innovative non-invasive technique, in vivo lung morphometry with hyperpolarized ³He MRI-to characterize lung microstructure in the pediatric lung transplant population. This technique yields quantitative measurements of acinar airways' (alveolar ducts and sacs) parameters, such as acinar airway radii and alveolar depth. Six pediatric lung transplant recipients with cystic fibrosis underwent in vivo lung morphometry MRI, pulmonary function testing, and quantitative CT. We found a strong correlation between lung lifespan and alveolar depth-patients with more shallow alveoli were likely to have a negative outcome sooner than those with larger alveolar depth. Combining morphometric results with CT, we also determined mean alveolar wall thickness and found substantial increases in this parameter in some patients that negatively correlated with DLCO. In vivo lung morphometry uniquely provides previously unavailable information on lung microstructure that may be predictive of a negative outcome and has a potential to aid in lung selection for transplantation.

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 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.

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.

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.

Transcatheter closure of an atrial septal defect, patent foramen ovale, or post-myocardial infarction ventricular septal defect has become a safe and effective alternative to medical and surgical therapy. Although the use of transcatheter closure of septal defects is becoming increasingly more popular, there are few reports of the radiographic appearance of the closure devices. We report the chest radiographic findings in 36 patients after transcatheter closure of septal defects with Amplatzer or CardioSEAL occluders in an effort to aid radiologists in recognizing the appearances of these devices and enable them to confirm proper positioning.

Anopthalmia/microphthlamia-esophageal atresia association with additional features imperforate anus, choanal atresia, cyanotic heart disease

MR imaging is well suited to evaluation of the pelvis. Ultrasonography remains the study of choice for the initial evaluation of a suspected gynecologic mass. MR imaging and computed tomography remain problem-solving tools that can help to characterize masses and stage gynecologic malignancies. MR imaging has the advantage of higher soft tissue contrast compared with computed tomography. This article reviews the MR findings of congenital anomalies and masses of the adnexa and uterus in adolescent girls.

To compare the accuracies of computed tomography (CT), magnetic resonance (MR) imaging, and bone scintigraphy in staging disease in patients with neuroblastoma.Ninety-six children with newly diagnosed neuroblastoma were enrolled in a multicenter prospective cohort study. CT, MR, and bone scintigraphy were used to evaluate tumor stage. Sensitivity and specificity values and receiver operating characteristic (ROC) curve analyses were used to compare the accuracy of CT, MR, and scintigraphy for tumor staging.Eighty-eight patients were eligible for staging analysis, and 45 patients who underwent surgery at initial diagnosis were eligible for analysis of local tumor extent. CT and MR had sensitivities of 43% and 83%, respectively (P.01), and specificities of 97% and 88%, respectively (P.05), for detection of stage 4 disease. Areas under the ROC curves for CT and MR were 0.81 and 0.85, respectively (P =.06); that for scintigraphy was 0.83. Addition of scintigraphy to both CT and MR increased the areas under the ROC curves to 0.90 and 0.88, respectively. Accuracy of CT and MR for staging disease confined to the chest or abdomen (stages 1, 2, and 3) was poor.MR alone and CT and MR combined with bone scintigraphy enable the accurate detection of stage 4 disease. Both CT and MR perform poorly for local tumor staging.

Phosphaturic mesenchymal tumor is an uncommon cause of a paraneoplastic syndrome that can be associated with osteogenic osteomalacia. This tumor most commonly occurs in middle-aged men and women. We report a rare case of a phosphaturic mesenchymal tumor in a 16-year-old girl with multiple fractures as a result of severe osteoporosis. CT and MRI showed a mass arising from the tibia.

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 (SUV(max)) 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 SUV(max) 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 (P0.0001). 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.

Background: The diagnosis of esophageal atresia may be suspected on prenatal ultrasound scan in fetuses with a small or absent stomach or unexplained polyhydramnios. However, these findings are thought to have a low positive predictive value and clinical decisions affecting timing or site of delivery may be made erroneously. The authors evaluated the accuracy of fetal sonography followed by magnetic resonance imaging (MRI) for the diagnosis of this lesion. Methods: Fetuses considered to be at risk for esophageal atresia based on detailed obstetric sonography underwent fetal MRI using a single-shot rapid-acquisition technique, and the T 2 -weighted images were evaluated prospectively. Scans were considered to be positive if the proximal esophagus was dilated, and the distal esophagus was not seen and negative if the esophagus was visualized throughout its length. Results: Ten fetuses underwent MRI scanning. All had a small or absent stomach bubble with unexplained polyhydramnios. Four scans were considered to be negative for esophageal atresia; all 4 were found to have a normal esophagus after delivery. Six scans were considered to be positive; 5 had esophageal atresia (2 with tracheoesophageal fistula and 3 without), and one had a neurologic syndrome with a normal esophagus. Conclusions: Magnetic resonance imaging appears to be accurate for establishing or ruling out a prenatal diagnosis of esophageal atresia, and should be considered in fetuses who are at high risk based on ultrasound findings. J Pediatr Surg 36:804-807. Copyright © 2001 by W.B. Saunders Company.

OBJECTIVE To assess the sonographic findings of breast masses in adolescents and the usefulness of sonographic patterns for suggesting a specific diagnosis. METHODS The sonograms and medical records of 57 girls (mean age, 15.4 years) with palpable breast masses were retrospectively reviewed. Three observers reviewed the sonograms for multiple sonographic findings. Surgery or clinical findings established diagnoses. Statistical analysis was done to determine how well sonographic findings alone and in combination agreed with final histologic diagnoses. RESULTS Diagnoses included cysts (n = 12), abscesses (n = 7), fibroadenomas (n = 36), a lactating adenoma (n = 1), and a phyllodes tumor (n = 1). The sonographic findings varied significantly among lesion types (P < or = .005). CONCLUSIONS Our experience suggests that virtually all breast masses in a pediatric population are benign and that sonography has the ability to differentiate among cystic, inflammatory, and solid masses.

Autosomal dominant polycystic disease with associated arachnoid cysts and subdural cystic hygroma requiring shunting

To study the appearance and distribution of posttransplantation lymphoproliferative disorder (PTLD) at abdominal computed tomography (CT).The authors retrospectively analyzed pretreatment abdominal CT scans in 51 patients (mean age, 36 years) with PTLD after solid organ transplantation. All diagnoses were proved at either abdominal (n = 26) or extraabdominal (n = 25) pathologic examination. Presence or absence of abdominal involvement, appearance and distribution of disease, and association with abdominal symptoms were all analyzed.CT scans were abnormal in 36 of the 51 patients (71%). Fifteen patients (29%) had no CT, clinical, or pathologic evidence of abdominal involvement. Of the 36 patients with abdominal PTLD at CT, 22% had lymph node enlargement, 28% splenic involvement, and 81% extranodal or extrasplenic involvement. Extranodal abdominal sites included liver (53%), small bowel (25%), kidney (17%), mesentery (14%), adrenal gland (8%), abdominal wall (8%), colon (6%), stomach (3%), and gallbladder (3%). Frequency of abdominal involvement was greater for heart and liver transplant recipients (94%) than for lung and kidney transplant recipients (58%) (P.01). Seventeen of 36 patients (47%) with abdominal PTLD had no evidence of extraabdominal disease.Extranodal involvement is more common than splenic or nodal involvement in patients with abdominal PTLD. The presence of such findings in a patient after transplantation strongly suggests the diagnosis of PTLD and warrants aggressive evaluation.

OBJECTIVE. Our objective was to characterize the CT findings in children with acute appendicitis and to compare the CT appearance of the normal and abnormal appendix. MATERIALS AND METHODS. CT scans of 20 children (mean age, 8.6 years old) with surgically proven appendicitis were retrospectively reviewed. The CT studies were evaluated for the presence of a visualized appendix, appendiceal caliber and wall thickness, appendicoliths, pericecal inflammation, and abscess. Fifty children of similar age to the study group who did not have an appendicitis and who had undergone CT scans for acute trauma served as the control population. RESULTS. CT scans revealed the appendix in 25 (50%) of 50 control patients and in 11 (55%) of 20 patients with appendicitis. Appendiceal diameter ranged between 3 and 8 mm (mean, 6 mm) in the control group and between 8 and 12 mm (mean, 10 mm) in patients with appendicitis (p i) of 20 patients with appendicitis and in none of the control patients. Pericecal inflammation was seen in 19 (95%) of 20 patients with appendicitis and abscess was seen in 10 (50%) of 20 patients. Specific signs of appendicitis, defined as either an inflamed appendix or appendicolith with associated inflammatory changes, were seen in 16 (80%) of 20 patients. CONCLUSION. Our results suggest that CT findings of the healthy appendix are distinct from those of the abnormal appendix and that CT scans can be useful in diagnosing appendicitis in a pediatric population.

To assess effects of an automated kilovoltage selection tool on radiation dose, tube current, and image quality in pediatric contrast material-enhanced thoracoabdominal computed tomography (CT) and CT angiography.The institutional review board approved this retrospective study of 87 children (median age, 10.5 years; age range, 1 day to 19 years) who underwent thoracic CT, abdominal CT, or CT angiography with an automated kilovoltage protocol between November 2010 and July 2011. Volumetric CT dose index (CTDIvol) and milliamperage were compared with estimated prescanning calculations from a standard 120-kVp protocol. Image quality was subjectively scored on a scale of 1 to 5. In 15 patients who underwent scanning with both automated kilovoltage and standard 120-kVp protocols, image contrast and noise were quantitatively measured and the contrast-to-noise ratio (CNR) was calculated. Parametric and/or nonparametric testing of independent and/or paired samples was performed.Estimated median CTDIvol for all 87 studies was 4.8 mGy for the automated kilovoltage protocol versus 7.1 mGy for the 120-kVp protocol, yielding a 27% dose reduction (25% and 75% percentiles: 23% and 37%, respectively; P.001). The median milliamperage was 125.0 with the automated protocol and 87 with the 120-kVp protocol (P.001). Use of automated kilovoltage selection resulted in kilovoltage reduction from 120 kVp in 82 of the 87 patients (94%), with the percentage dose reduction greater for CT angiography than for chest CT (P.001). Reduction in kilovoltage showed a significant correlation with patient size (P.01). Diagnostic image quality was achieved in all patients. Mean contrast and noise were higher with the automated kilovoltage protocol than with the 120-kVp protocol (P ≤ .04), but CNRs for liver and portal vein were similar (P = .54 and .73, respectively).In pediatric CT and CT angiography, the use of automated kilovoltage selection technology significantly reduces radiation dose while maintaining image quality and CNR.

To evaluate flow velocity measurements in the middle cerebral artery (MCA) and/or neurologic examination for detection of cerebral infarction in sickle cell disease (SCD).Twenty-four pediatric patients aged 6 1/2-17 years with SCD underwent magnetic resonance (MR) imaging, MR angiography, neurologic examination, and transcranial Doppler ultrasonography (US). Transcranial Doppler studies were evaluated for maximum flow velocity in the right and left MCAs. Combinations of cut-off values were used to determine the sensitivity and specificity of transcranial Doppler US for detection of infarction.Neurologic examination had 58% sensitivity and 92% specificity for cerebral infarction. Maximal flow velocity200 cm/sec or100 cm/sec (including no flow) helped identify nine of 12 patients with infarcts proved at MR imaging, with only one false-positive result (sensitivity, 75%; specificity 92%). The combination of neurologic examination and transcranial Doppler US produced 92% sensitivity and 83% specificity for cerebral infarction.The combination of transcranial Doppler US and neurologic examination has potential as a screening technique for infarction in SCD.

We determined the accuracy of neurologic examination and the history of a previous neurologic event in detecting clinical evidence of a magnetic resonance imaging (MRI)-diagnosed cerebral infarction in 30 children with sickle cell hemoglobinopathy. Each patient had an MRI of the brain, neurologic examination, chart review, and psychometric evaluation. Seventeen children (57%) had MRI evidence of cerebral infarction based on demonstration of parenchymal abnormalities in a vascular distribution. Among the 17 children with MRI evidence of cerebral infarction, only 12 (71%) had an abnormal neurologic examination, and 11 (65%) had a history of a prior neurologic event. In contrast, among the 13 children with normal MRIs, 12 (92%) had normal neurologic examinations, and no child had a previous history of a neurologic event. Multiple, bilateral, heterogeneous cerebral infarctions frequently occur without overt neurologic signs or symptoms in children with sickle cell hemoglobinopathy. Previous studies that relied on a focal neurologic examination or a history of a neurologic event to identify cerebral infarctions in patients with sickle cell hemoglobinopathy most likely underrepresented the true frequency of cerebral infarctions in this population. Future prospective studies of cerebral infarctions in children with sickle cell hemoglobinopathy should include MRIs for identification and classification, rather than neurologic examination or clinical history alone. (J Child Neurol 1995;10:88-92).

We conducted this study to determine if color Doppler ultrasonography can identify increased vascularity associated with gastrointestinal inflammatory conditions and to determine if specific diagnoses can be established based on flow patterns. Twenty-five children with acute right lower quadrant pain and discharge diagnoses of inflammatory bowel processes were examined by color Doppler sonography, as an adjunct to routine gray-scale examinations. Final diagnoses included gastroenteritis (10 cases), Crohn's disease (five cases), neutropenic colitis (four cases), peritonitis (four cases), and Yersinia enterocolitis (two cases). The results of color Doppler sonography were considered positive for inflammation if increased vascularity was demonstrated in the bowel mucosa, muscularis layer, or adjacent tissues. A control group of 19 patients was examined. No sonographic abnormalities were identified in any patients in the control group. Diffuse, concentric wall thickening with increased blood flow centrally within the mucosa was seen in Crohn's disease (60%) and Yersinia enterocolitis (100%), whereas wall thickening with increased transmural vascularity was identified in neutropenic colitis (50%) and Crohn's disease (40%). In contrast, in peritonitis color Doppler sonography showed thickened bowel wall and hypervascularity within peripheral bowel wall or in adjacent soft tissues. No demonstrable bowel vascularity was seen in gastroenteritis. Our experience suggests that mucosal or transmural hypervascularity on color Doppler sonography can be seen with several inflammatory bowel processes, but it is nonspecific. However, color Doppler sonography may aid in differentiating primary bowel disease from extrinsic inflammatory conditions, such as peritonitis.

Relapsed or refractory (rel/ref) classical Hodgkin lymphoma (cHL) remains a clinical challenge, with limited effective treatment options available after stem cell transplantation. In a multicenter phase 2 study, the efficacy of lenalidomide in rel/ref cHL patients was evaluated at a dose of 25 mg/d on days 1-21 of a 28-day cycle. Patients remained on lenalidomide until disease progression or an unacceptable adverse event (AE) occurred. Thirty-eight cHL patients were enrolled with a median of 4 (range, 2-9) prior therapies; 87% had undergone prior stem cell transplantation and 55% of patients did not respond to their last prior therapy. Of 36 evaluable patients, responses were 1 complete remission (CR), 6 partial remissions (PRs), and 5 patients with stable disease (SD) for ≥ 6 months resulting in an International Working Committee (IWC) objective overall response rate (ORR) of 19% and a cytostatic ORR of 33%. Decreased chemokine (CCL17 and CCL22) plasma levels at 2 weeks were associated with a subsequent response. The treatment was well tolerated, and the most common grade 3/4 AEs were neutropenia (47%), anemia (29%), and thrombocytopenia (18%). Four patients discontinued lenalidomide because of rash, elevated transaminases/bilirubin, and cytopenias. We provide preliminary evidence of lenalidomide's activity in patients with rel/ref cHL, and therefore exploration of lenalidomide in combination with other active agents is warranted. This trial is registered at www.ClinicalTrials.gov as NCT00540007.

Clubfoot affects 1 in 1000 live births, although little is known about its genetic or developmental basis. We recently identified a missense mutation in the PITX1 bicoid homeodomain transcription factor in a family with a spectrum of lower extremity abnormalities, including clubfoot. Because the E130K mutation reduced PITX1 activity, we hypothesized that PITX1 haploinsufficiency could also cause clubfoot. Using copy number analysis, we identified a 241 kb chromosome 5q31 microdeletion involving PITX1 in a patient with isolated familial clubfoot. The PITX1 deletion segregated with autosomal dominant clubfoot over three generations. To study the role of PITX1 haploinsufficiency in clubfoot pathogenesis, we began to breed Pitx1 knockout mice. Although Pitx1(+/-) mice were previously reported to be normal, clubfoot was observed in 20 of 225 Pitx1(+/-) mice, resulting in an 8.9% penetrance. Clubfoot was unilateral in 16 of the 20 affected Pitx1(+/-) mice, with the right and left limbs equally affected, in contrast to right-sided predominant hindlimb abnormalities previously noted with complete loss of Pitx1. Peroneal artery hypoplasia occurred in the clubfoot limb and corresponded spatially with small lateral muscle compartments. Tibial and fibular bone volumes were also reduced. Skeletal muscle gene expression was significantly reduced in Pitx1(-/-) E12.5 hindlimb buds compared with the wild-type, suggesting that muscle hypoplasia was due to abnormal early muscle development and not disuse atrophy. Our morphological data suggest that PITX1 haploinsufficiency may cause a developmental field defect preferentially affecting the lateral lower leg, a theory that accounts for similar findings in human clubfoot.

Solitary Hepatic Hemangioendothelioma with Extensive Cystic Necrosis and Markedly Elevated α-Fetoprotein

Special Imaging casebook: Hypoplastic Left Heart, Prostaglandin Therapy Gastric Focal Foveolar Hyperplasia and Brown-Fat Necrosis

Lower extremity vascular anomalies have been described for patients with clubfoot but few imaging studies have investigated effects on soft tissues such as fat and muscle. To make these assessments we need noninvasive, noncontrast agents to more safely image children.We describe a novel noninvasive imaging protocol to identify vascular and soft tissue abnormalities in the lower limbs of patients with clubfoot and determine whether these abnormalities are present in patients who had recurrent clubfoot.Three-dimensional noncontrast-enhanced MR angiography was used to identify vascular, bone, and soft tissue abnormalities in patients with clubfoot. We determined whether these abnormalities were more common in patients who had experienced recurrent clubfoot.Four patients with isolated unilateral clubfoot had arterial anomalies in the clubfoot limb. All patients had less muscle volume in the affected limb, and nine of 11 patients (82%) had less subcutaneous fat, with a mean difference of 0.56 cm(3) ± 0.36 cm(3) (range, 0.08-1.12 cm(3)). Vascular anomalies and decreased fat and muscle volumes were present in all three patients with recurrent clubfoot.We found a high frequency of vascular and soft tissue anomalies in the affected limbs of patients with unilateral clubfoot that may correlate with response to treatment.

Congenital collision tumors, neonatal renal mesoblastic nephroma and pararenal paraganglioma