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Background/objectives: To compare different imaging procedures [cone beam computed tomography (CBCT), computed tomography (CT), magnetic resonance imaging (MRI), orthopantomography (OPG), and lateral cephalometry (LC)] for assessing the mandibular height [ramus height (RH)] and condylar process (CondProc) length as they reflect mandibular growth., Materials/methods: The RH and CondProc of eight cadaver heads (each side separately) were measured using CBCT, CT, MRI, OPG, and LC. They were measured twice by two independent observers parallel to the posterior border of the mandibular ramus. An intraclass correlation coefficient (ICC) was used to assess the inter- and intraobserver reliability. The coefficient of variation was used to elucidate precision. Bland-Altman (BA) plots were used to assess the agreement between the procedures and the intra- and interobserver measurements., Results: All procedures, with the exception of LC, showed good intra- and interobserver agreement (maximum range of agreement: 5.3mm) and excellent reliability (ICC > 0.9). The BA plot analysis for the CondProc and RH showed similar ranges of agreement between MRI, CT, and CBCT (maximum 6.4mm) but higher ranges for OPG and LC. The MRI and OPG values were generally smaller., Conclusions/implications: All 3D imaging procedures yielded nearly equal results when used to measure the CondProc and RH. MRI is recommended because it avoids ionizing radiation and has higher sensitivity in the detection of inflammation. A 2-year threshold for detecting growth in the follow-up period should be taken into account for all 3D imaging methods. Measuring the RH is recommended for the follow-up of condylar growth because reference values for annual increments are published., (© The Author 2014. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Objective: To investigate Port-A-Cath (PAC)-related thrombosis and postthrombotic syndrome (PTS) in children with cancer., Study Design: The study population was a consecutive cohort of children diagnosed with cancer and a PAC implanted at diagnosis. Children were evaluated for the presence of PAC-related thrombosis by magnetic resonance venography and the presence of congenital prothrombotic risk factors and PTS., Results: A total of 114 children (median age, 6.04 years) were included. Of these children, 48 (42%) were treated for solid tumors and 66 (58%) were treated for hematopoietic tumors, including 38 for acute lymphoblastic leukemia. At the time of magnetic resonance venography, 42 children (37%) had the PAC still in place, and 72 (63%) had the PAC removed. Overall, PACs were in place for a total of 324.92 PAC-years. PAC-related thrombosis was detected in 45 children (39.5%) with a current or previous PAC. Of these, 21 (47%) had a solid tumor, 14 (31%) had acute lymphoblastic leukemia, and 10 (22%) had another hematopoietic tumor. Younger age at diagnosis, female sex, duration of PAC use, and left-side PAC placement were independently associated with an increased risk of thrombosis, whereas asparaginase therapy and the presence of inherited prothrombotic risk factors were not. Mild PTS (ie, presence of prominent collateral vessels in the skin) was present in 5.6% of the children., Conclusion: PAC-related thrombosis is common in pediatric oncology patients. In some children, thrombotic complications can lead to the development of PTS., (Copyright © 2013 Mosby, Inc. All rights reserved.)

Significant pulmonary regurgitation (PR) after repair of tetralogy of Fallot (TOF) may affect flow in the pulmonary artery (PA) side branches. We sought to assess flow changes and distensibility of the PA side branches in vivo and test correlation with the degree of PR and right-ventricular (RV) dilatation. Thirty patients after TOF repair and 16 controls underwent cardiovascular magnetic resonance for quantification of RV volumes and measurement of flow in the PA side branches. RV volumes and function, blood flow volumes, and cross-sectional area of the main, left (LPA), and right (RPA) PA were measured and regurgitant volumes and distensibility calculated. Results were compared between the LPA and the RPA and between patients and controls. Median regurgitation fraction of PR was 41 % (range 22-60 %). Regurgitant fraction was greater in the LPA (40 %) than in the RPA (29 %), resulting in lower net flow into the LPA (p < 0.001). LPA area was significantly greater than that of the RPA (303.9 vs. 232.7 mm(2)/m(2)) (p < 0.0001). The LPA showed lower distensibility than the RPA (39 vs. 44 %). PA side branch distensibility correlated with MPA regurgitant volume (p = 0.001), MPA regurgitant fraction (p = 0.001), and RV end-diastolic volume (p = 0.03). PA side branches have greater distensibility in patients with PR than in normal subjects. Significant PR leads to changes in flow profile and distensibility of the PA side branches. The LPA shows greater regurgitant volume and greater area but lower distensibility than the RPA.

Introduction: This study seeks to evaluate the diagnostic accuracy of cerebral perfusion imaging with arterial spin labelling (ASL) MR imaging in children with moyamoya disease compared to dynamic susceptibility contrast (DSC) imaging., Methods: Ten children (7 females; age, 9.2 ± 5.4 years) with moyamoya disease underwent cerebral perfusion imaging with ASL and DSC on a 3-T MRI scanner in the same session. Cerebral perfusion images were acquired with ASL (pulsed continuous 3D ASL sequence, 32 axial slices, TR = 5.5 s, TE = 25 ms, FOV = 24 cm, matrix = 128 × 128) and DSC (gradient echo EPI sequence, 35 volumes of 28 axial slices, TR = 2,000 ms, TE = 36 ms, FOV = 24 cm, matrix = 96 × 96, 0.2 ml/kg Gd-DOTA). Cerebral blood flow maps were generated. ASL and DSC images were qualitatively assessed regarding perfusion of left and right ACA, MCA, and PCA territories by two independent readers using a 3-point-Likert scale and quantitative relative cerebral blood flow (rCBF) was calculated. Correlation between ASL and DSC for qualitative and quantitative assessment and the accuracy of ASL for the detection of reduced perfusion per territory with DSC serving as the standard of reference were calculated., Results: With a good interreader agreement (κ = 0.62) qualitative perfusion assessment with ASL and DSC showed a strong and significant correlation (ρ = 0.77; p < 0.001), as did quantitative rCBF (r = 0.79; p < 0.001). ASL showed a sensitivity, specificity and accuracy of 94 %, 93 %, and 93 % for the detection of reduced perfusion per territory., Conclusion: In children with moyamoya disease, unenhanced ASL enables the detection of reduced perfusion per vascular territory with a good accuracy compared to contrast-enhanced DSC.

Introduction: The aims of this study were to compare lateral cephalograms with other radiologic methods for diagnosing suspected fusions of the cervical spine and to validate the assessment of congenital fusions and osteoarthritic changes against the anatomic truth., Methods: Four cadaver heads were selected with fusion of vertebrae C2 and C3 seen on a lateral cephalogram. Multidetector computed tomography (MDCT) and cone-beam computed tomography (CBCT) were performed and assessed by 5 general radiologists and 5 oral radiologists, respectively. Vertebrae C2 and C3 were examined for osseous fusions, and the left and right facet joints were diagnosed for osteoarthritis. Subsequently, the C2 and C3 were macerated and appraised by a pathologist. Descriptive analysis was performed, and interrater agreements between and within the groups were computed., Results: All macerated specimens showed osteoarthritic findings of varying degrees, but no congenital bony fusion. All observers agreed that no fusion was found on MDCT or CBCT. They disagreed on the prevalence of osteoarthritic deformities (general radiologists/MDCT, 100%; oral radiologists/CBCT, 93.3%) and joint space assessment in the facet joints (kappa = 0.452). The agreement within the rater groups differed considerably (general radiologists/MDCT, kappa = 0.612; oral radiologists/CBCT, kappa = 0.240)., Conclusions: Lateral cephalograms do not provide dependable data to assess the cervical spine for fusions and cause false-positive detections. Both MDCT interpreted by general radiologists and CBCT interpreted by oral radiologists are reliable methods to exclude potential fusions. Degenerative osteoarthritic changes are diagnosed more accurately and consistently by general radiologists evaluating MDCT., (Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

Objective: To determine the best suited sagittal MRI sequence out of a standard temporo-mandibular joint (TMJ) imaging protocol for the assessment of the cortical bone of the mandibular condyles of cadaveric specimens using micro-CT as the standard of reference., Methods: Sixteen TMJs in 8 human cadaveric heads (mean age, 81 years) were examined by MRI. Upon all sagittal sequences, two observers measured the cortical bone thickness (CBT) of the anterior, superior and posterior portions of the mandibular condyles (i.e. objective analysis), and assessed for the presence of cortical bone thinning, erosions or surface irregularities as well as subcortical bone cysts and anterior osteophytes (i.e. subjective analysis). Micro-CT of the condyles was performed to serve as the standard of reference for statistical analysis., Results: Inter-observer agreements for objective (r = 0.83-0.99, P < 0.01) and subjective (κ = 0.67-0.88) analyses were very good. Mean CBT measurements were most accurate, and cortical bone thinning, erosions, surface irregularities and subcortical bone cysts were best depicted on the 3D fast spoiled gradient echo recalled sequence (3D FSPGR)., Conclusion: The most reliable MRI sequence to assess the cortical bone of the mandibular condyles on sagittal imaging planes is the 3D FSPGR sequence., Key Points: MRI may be used to assess the cortical bone of the TMJ. • Depiction of cortical bone is best on 3D FSPGR sequences. • MRI can assess treatment response in patients with TMJ abnormalities.

Introduction: Yet unreported in this lysosomal storage disease, we aimed to quantify our observation that patients with fucosidosis may show abnormally increased cerebellar volumes during early childhood., Methods: Five normocephalic fucosidosis patients (age range 2-25 months, three males) were included in this retrospective case control study. The control cohort consisted of 25 children (age range 0-36 months, 15 males). Image postprocessing was performed independently by two radiologists. Using validated software, manual tracing of contours on contiguous sagittal magnetic resonance images was allowed for cerebellar volumetry. We tested the null hypothesis that mean cerebellar volumes of four fucosidosis patients (age 16, 20, 21, and 25 months) and of an age-matched control cohort (n = 8, age range 13-26 months) were equal based on a two-tailed unpaired t-test., Results: Interobserver agreement was excellent (R = 1, p < 0.01). A rough trajectory of normal cerebellar development appeared to flatten around the age of 1 year. With mean volumes of 121.36 and 102.30 ml, respectively, cerebellar volumes of fucosidosis patients with a mean age of 21 months were significantly increased compared to age-matched controls (p < 0.05). In a single patient, longer-term follow-up with MRI at the age of 47 months was available and showed cerebellar atrophy., Conclusion: Increased cerebellar volume was shown to be an additional feature in the early stage of fucosidosis. The combination with a confirmed tendency toward atrophy of the cerebellum during later course of the disease is probably unique in the context of metabolic disorders of the brain.

Purpose: In this clinical investigation, we aimed (1) to re-evaluate the nature of glioneuronal tissue with transsphenoidal extension and how it fits into the nomenclature of midline malformations and mass lesions; (2) to find out if our imaging findings support current pathoanatomic concepts of clefts and canals in the sphenoid body of newborns., Methods: In two neonates with respiratory distress due to nasopharyngeal masses, 3T MRI was performed, and CT in one of them. Imaging features were analyzed in consensus by two pediatric neuroradiologists with histological reports being available. An interdisciplinary panel compared the findings to those of case publications and differential entities from our institutional case collection., Results: Referring to our rare case of transsphenoidal cerebral heterotopia and unique case of hypothalamic hamartoma with transsphenoidal herniation, glioneuronal heterotopia may definitely extend through the sphenoid bone. Consequently, there is reason for brain heterotopias to be labeled as such also in case of an intracranial component. Connection between heterotopic glioneuronal tissue in the nasopharynx and a hypothalamic hamartoma may go along with indistinct margins to normal brain. Neither extension through a transsphenoidal cleft nor association with a cleft palate are specific for cerebral heterotopia. Our findings support the hypothesis that transsphenoidal cerebral heterotopias do not or at least not invariably follow the route of Rathke's pouch, known as the craniopharyngeal canal., Conclusion: Transsphenoidal glioneuronal heterotopia should be the top differential diagnosis in MR imaging if a non-enhancing nasopharyngeal mass of an infant extends through a craniopharyngeal cleft within the intersphenoid synchondrosis.

We sought to establish normal values for the diameters of the main (MPA), right (RPA), and left (LPA) pulmonary arteries and for the angles describing the geometry of the pulmonary artery bifurcation in children by using contrast-enhanced magnetic resonance angiography (CE-MRA). CE-MRA was performed in 69 children without cardiovascular disease. The median age was 10 ± 4.9 years (range 2-20), weight 37.4 ± 18.5 kg (10-82), body surface area (BSA) 1.18 ± 0.4 m(2) (0.48-2.07). The pulmonary artery diameters and angles were measured at standardized sites and projections. Regression analysis of diameters and angles in relation to BSA demonstrated linear relationship between the cross-sectional diameters of the pulmonary arteries and the square root of BSA (BSA(0.5)). Normalized mean diameters were for the MPA 17.6 ± 5.1 mm/m(2), origin of RPA 13.1 ± 2.9 mm/m(2), origin of LPA 14.2 ± 2.9 mm/m(2). The MPA showed a mean antero-posterior inclination of 33° ± 8° and a lateral leftward angulation of 18° ± 5°. The mean angle of the bifurcation was 99.5° ± 10.3°. Both side branches showed a supero-inferior course of the proximal segments, steeper for the RPA (7.7° ± 6.5°) than for the LPA (2.1° ± 7.8°). Normative curves in relation to BSA are presented for all measurements. This study provides normative values by CE-MRA for the main pulmonary artery and its side branches in children during somatic growth. These data can be used for identifying pulmonary arteries anomalies in children, and evaluate the need and the modality for treatment., (© Springer Science+Business Media, B.V. 2010)

Aims: As coronary artery disease may also occur during childhood in some specific conditions, we sought to assess the feasibility and accuracy of perfusion cardiovascular magnetic resonance (CMR) in paediatric patients., Methods and Results: First-pass perfusion CMR studies were performed under pharmacological stress with adenosine and by using a hybrid echo-planar pulse sequence with slice-selective saturation recovery preparation. Fifty-six perfusion CMR examinations were performed in 47 patients. The median age was 12 years (1 month-18 years), and weight 42.8 kg (2.6-82 kg). General anaesthesia was required in 18 patients. Mean examination time was 67 +/- 19 min. Diagnostic image quality was obtained in 54/56 examinations. In 23 cases the acquisition parameters were adapted to patient's size. Perfusion CMR was abnormal in 16 examinations. The perfusion defects affected the territory of the left anterior descending coronary artery in 11, of the right coronary artery in 3, and of the circumflex coronary artery in 2 cases. Compared to coronary angiography, perfusion CMR showed a sensitivity of 87% (CI 52-97%) and a specificity of 95% (CI 79-99%)., Conclusion: In children, perfusion CMR is feasible and accurate. In very young children (less than 1 year old), diagnostic image quality may be limited.

Background: Quantification of ventricular volume by steady state free precession (SSFP) cardiovascular magnetic resonance is accurate and reproducible. Normal values exist for adults, but are lacking for children.We sought to establish normal values for left and right ventricular volumes, mass and function in healthy children by using SSFP., Methods and Results: Fifty children (27 females, 23 males) without cardiovascular disease were evaluated. Median age was 11 years (range 7 months - 18 years), weight 35 kg (range 7-77 kg), height 146 cm (range 66-181 cm). Thirty-six examinations were performed with breath holding, 14 in freely breathing sedated children.Ventricular volumes and mass were measured in the end systolic and end diastolic phase on SSFP cine images acquired in a short axis plane as a stack of 12 contiguous slices covering full length of both ventricles. Regression analysis showed an exponential relationship between body surface area (BSA) and ventricular volumes and mass (normal value = a*BSAb). Normative curves for males and females are presented in relation to BSA for the end-diastolic volume, end-systolic volume and mass of both ventricles. Intra- and interobserver variability of the measurements was within the limits of 2% and 7% respectively, except for right ventricular mass (10%)., Conclusion: The exponential equation for calculation of normal values for each ventricular parameter and graphical display of normative curves for data acquired in healthy children by SSFP cardiovascular magnetic resonance are provided.

As children are not small adults, imaging evaluation needs to be adapted to their special features and diseases. This article discusses the imaging strategy for typical paediatric pathologies of the brain and skull, spinal cord and spine, chest, abdomen and musculoskeletal system. The most important consideration when imaging children is to optimise and reduce unnecessary or unnecessarily high radiation exposure. Whenever available, a radiation free imaging modality should be chosen. Ultrasound is considered the primary examination method in many circumstances and often reveals sufficient information. For advanced imaging of the abdomen, brain or musculoskeletal system, magnetic resonance imaging should be preferred over computed tomography (CT). Conventional radiographs remain the primary imaging modality for evaluation of the chest and bones. CT should be reserved for further evaluation of the lungs and airways, or for the emergent investigation of a major head injury or polytrauma. Every imaging study with ionising radiation requires a justifying medical indication. Radiography, fluoroscopy and CT should be performed on optimised equipment using special paediatric protocols in order to achieve a radiation exposure as low as possible.

Objective: This study was undertaken to describe the radiographic and MRI appearances of arthropathy of the knees in 14 patients with beta-thalassemia major undergoing chelation therapy with deferiprone (L1)., Materials and Methods: All available radiographs and MRI studies of the knees in 14 beta-thalassemia major patients (mean age, 16.3 years; age range, 7-33 years) undergoing chelation therapy with L1 were retrospectively assessed for changes in the synovium, cartilage, and bone. Imaging findings and signs of knee arthropathy were correlated with chelation therapy and average serum ferritin concentration., Results: Nine (64%) of the 14 patients developed arthralgia of the knees during treatment with L1. Abnormal imaging findings were present in all symptomatic and two asymptomatic patients (12/14, 86%) and included joint effusion, subchondral bone irregularity, and patellar beaks. Additional MRI findings were thickening and enhancement of the synovium; hypointense bands in the synovium; irregularly thickened epiphyseal and articular cartilage overlying subchondral bone defects; and, on T2-weighted sequences, hyperintense articular cartilage lesions. The degree of knee symptoms at the time of imaging did not reflect the severity of cartilage and subchondral bone changes., Conclusion: Radiologic changes can be seen in L1-related arthropathy and should be recognized. MRI of the knees should be considered in symptomatic children and young adults with thalassemia undergoing L1 chelation therapy for iron overload.