Developmental Curves of the Paediatric Brain Using FLAIR MRI Texture Biomarkers.

Analysis of FLAIR MRI sequences is gaining momentum in brain maturation studies, and this study aimed to establish normative developmental curves for FLAIR texture biomarkers in the paediatric brain. A retrospective, single-centre dataset of 465/512 healthy paediatric FLAIR volumes was used, with one pathological volume for proof-of-concept. Participants were included if the MRI was unremarkable as determined by a neuroradiologist.

Brain Volumes in Opsoclonus-Myoclonus Ataxia Syndrome: A Longitudinal Study.

Introduction: Little is known about the longitudinal trajectory of brain growth in children with opsoclonus-myoclonus ataxia syndrome. We performed a longitudinal evaluation of brain volumes in pediatric opsoclonus-myoclonus ataxia syndrome patients compared with age- and sex-matched healthy children.

Patients And Methods: This longitudinal case-control study included brain magnetic resonance imaging (MRI) scans from consecutive pediatric opsoclonus-myoclonus ataxia syndrome patients (2009-2020) and age- and sex-matched healthy control children.

Increased rate of significant findings on brain MRI during the early stage of the COVID-19 pandemic.

Objectives: To assess the effect of the COVID-19 pandemic on the proportion of abnormal paediatric neuroimaging findings as a surrogate marker for potential underutilisation.

Methods: Consecutive paediatric brain MRIs performed between March 27th and June 19th 2019 (T) and March 23rd and June 1st 2020 (T) were reviewed and classified according to presence or absence and type of imaging abnormality, and graded regarding severity on a 5-point Likert scale, where grade 4 was defined as abnormal finding requiring non-urgent intervention and grade 5 was defined as acute illness prompting urgent medical intervention. Non-parametric statistical testing was used to assess for significant differences between T vs.

MRI Volumetric Analysis of the Hypothalamus and Limbic System across the Pediatric Age Span.

Purpose: Literature is scarce regarding volumetric measures of limbic system components across the pediatric age range. The purpose of this study is to remedy this scarcity by reporting continuous volumetric measurements of limbic system components, and to provide consistent stratification data including age-related trajectories and sex-related differences in the pediatric age range in order to improve the recognition of structural variations that might reflect pathology.

Methods: In this retrospective study, MRI sequences of children with normal clinical MRI examinations of the brain acquired between January 2010 and December 2019 were included.

Volumetric differences of thalamic nuclei in children with trisomy 21.

Objectives: Histological studies have shown alterations of thalamic nuclei in patients with Down syndrome (DS). The correlation of these changes on MRI (magnetic resonance imaging) is unclear. Therefore, this study investigates volumetric differences of thalamic nuclei in children with DS compared to controls.

Fet-Net Algorithm for Automatic Detection of Fetal Orientation in Fetal MRI.

Identifying fetal orientation is essential for determining the mode of delivery and for sequence planning in fetal magnetic resonance imaging (MRI). This manuscript describes a deep learning algorithm named Fet-Net, composed of convolutional neural networks (CNNs), which allows for the automatic detection of fetal orientation from a two-dimensional (2D) MRI slice. The architecture consists of four convolutional layers, which feed into a simple artificial neural network.

Cerebral White Matter Tract Anatomy.

Advances in MR imaging techniques have allowed for detailed in vivo depiction of white matter tracts. The study of white matter structure and connectivity is of paramount importance in leukodystrophies, demyelinating disorders, neoplasms, and various cognitive, neuropsychiatric, and developmental disorders. The advent of advanced "function-preserving" surgical techniques also makes it imperative to understand white matter anatomy and connectivity, to provide accurate road maps for tumor and epilepsy surgery.

Data governance functions to support responsible data stewardship in pediatric radiology research studies using artificial intelligence.

The integration of human and machine intelligence promises to profoundly change the practice of medicine. The rapidly increasing adoption of artificial intelligence (AI) solutions highlights its potential to streamline physician work and optimize clinical decision-making, also in the field of pediatric radiology. Large imaging databases are necessary for training, validating and testing these algorithms.

Volumetric Analysis of Hearing-Related Structures of Brain in Children with GJB2-Related Congenital Deafness.

Background: Children with non-syndromic hereditary sensorineural hearing loss (SNHL) provide an opportunity to explore the impact of hearing on brain development. Objective: This study investigates volumetric differences of key hearing-related structures in children with gap junction protein beta 2 GJB2-related SNHL compared to controls. Materials and methods: Ninety-four children with SNHL (n = 15) or normal hearing (n = 79) were studied using automated volumetric segmentation.

Rotational Vertebrobasilar Insufficiency: Is There a Physiological Spectrum? Phase-Contrast Magnetic Resonance Imaging Quantification in Healthy Volunteers.

Background: Some cases of cerebral ischemia have been attributed to dynamic flow limitation in neck vessels. It however remains unknown whether this represents the extreme end of a physiological response.

Methods: Eighteen healthy volunteers were recruited to this prospective study.

Musculoskeletal ultrasound in hemophilia: Results and recommendations from a global survey and consensus meeting.

Introduction: For persons with hemophilia, optimization of joint outcomes is an important unmet need. The aim of this initiative was to determine use of ultrasound in evaluating arthropathy in persons with hemophilia, and to move toward consensus among hemophilia care providers regarding the preferred ultrasound protocols for global adaptation.

Methods: A global survey of hemophilia treatment centers was conducted that focused on understanding how and why ultrasound was being used and endeavored to move toward consensus definitions of both point-of-care musculoskeletal ultrasound (POC-MSKUS) and full diagnostic ultrasound, terminology to describe structures being assessed by ultrasound, and how these assessments should be interpreted.

Current status of MR imaging of juvenile idiopathic arthritis.

Juvenile idiopathic arthritis (JIA) is the most common chronic arthropathy in the pediatric population. Although the diagnosis is essentially clinical for many affected joints, MR imaging has become an important tool for the assessment of joints that are difficult to evaluate clinically, such as temporomandibular and sacroiliac joints, and for screening of inflammatory changes in the entire body by whole body MRI (WBMRI) assessment. The utilization of MR imaging is challenging in the pediatric population given the need for discrimination between pathological and physiological changes in the growing skeleton.

Dual phase infusion with bolus tracking: technical innovation for cardiac and respiratory navigated magnetic resonance angiography using extracellular contrast.

This technical innovation paper describes a technique for performing cardiac-gated, respiratory-navigated cardiovascular magnetic resonance angiography using an extracellular gadolinium-based contrast agent at 1.5 Tesla (T) with a dual phase bolus injection and slow infusion technique.

Magnetic resonance imaging with RF encoding on curved natural slices.

While the idea of using spatial encoding fields (SEM) for image formation has been proven, conventional wisdom still holds that a magnetic resonance imaging (MRI) system begins with a highly uniform magnetic field. In particular, radio frequency (RF) encoding MRIs designed and tested to date have largely used uniform magnetic fields. Here we demonstrate magnetic resonance imaging in a magnetic field with a built-in gradient that gives non-planar slices - curved surfaces - when the nuclear spins are excited with narrow band RF pulses.

A technique for rapid single-echo spin-echo T2 mapping.

A rapid technique for mapping of T(2) relaxation times is presented. The method is based on the conventional single-echo spin echo approach but uses a much shorter pulse repetition time to accelerate data acquisition. The premise of the new method is the use of a constant difference between the echo time and pulse repetition time, which removes the conventional and restrictive requirement of pulse repetition time >> T(1).

Sex differences in the human corpus callosum microstructure: a combined T2 myelin-water and diffusion tensor magnetic resonance imaging study.

Sex differences in structure and organization of the corpus callosum (CC) have been identified in healthy adults and may be linked to distinct functional lateralization and processing in men and women. Magnetic resonance imaging (MRI) has facilitated noninvasive assessment of CC sex differences in morphology by volumetric imaging and microstructural organization by diffusion tensor imaging (DTI). Incorporation of recently developed myelin-water fraction (MWF) imaging may improve our understanding of CC sex differences.

MR imaging at 3.0 T in children: technical differences, safety issues, and initial experience.

The high signal-to-noise ratio and contrast-to-noise ratio of 3.0-T magnetic resonance (MR) imaging can be used to obtain high-resolution thin-section images in a short acquisition time. These advantages are associated with an increased specific absorption rate (SAR) and more artifacts owing to B(1) inhomogeneity and increased susceptibility and chemical shift.

Quantitative permeability magnetic resonance imaging in acute ischemic stroke: how long do we need to scan?

Blood-brain barrier (BBB) permeability estimation with dynamic contrast-enhanced MRI (DCE-MRI) has shown significant potential for predicting hemorrhagic transformation (HT) in patients presenting with acute ischemic stroke (AIS). In this work, the effects of scan duration on quantitative BBB permeability estimates (KPS) were investigated. Data from eight patients (three with HT) aged 37-93 years old were retrospectively studied by directly calculating the standard deviation of KPS as a function of scan time.

Accurate liver T2 measurement of iron overload: a simulations investigation and in vivo study.

Purpose: To investigate the accuracy of T 2 liver iron quantification using different curve-fitting models under varying acquisition conditions, and to compare in iron-overloaded patients the reliability of rapid T 2 measurements against approved and slower T(2) protocols.

Materials And Methods: Simulations were conducted to assess the influence of various factors on the accuracy of T 2 measurement: curve-fitting model, signal-to-noise ratio (SNR), and echo time (TE) spacing. Fifty-four iron-overloaded pediatric patients were assessed using a standard T(2) and two variations of T 2 acquisitions.

Low detection rate of craniocervical arterial dissection in children using time-of-flight magnetic resonance angiography: causes and strategies to improve diagnosis.

Craniocervical arterial dissection is a frequent cause of childhood arterial ischemic stroke requiring prompt diagnosis and treatment. However, there is no universal guideline for diagnostic cerebrovascular imaging in children. We assessed the role of time-of-flight magnetic resonance angiography in diagnosing craniocervical arterial dissection.

Alteration of diffusion tensor parameters in postmortem brain.

In autopsy of humans, there is usually an interval of hours to days between death and tissue fixation, during which the cadaver is stored below room temperature to retard tissue autolysis. We have attempted to model this process and evaluate the alteration in diffusion indices of the postmortem brain in pigs, which were kept at 4 degrees C. The pigs were scanned prior to death and at 3, 6, 9, 12, 18, 24, 30, 36, 42, 48 and 72 h postmortem.

Pediatric MR cholangiopancreatography: principles, technique, and clinical applications.

High-quality magnetic resonance (MR) cholangiopancreatographic images are difficult to obtain in children due to the small caliber of the pediatric bile ducts and to motion artifacts. However, there has been ongoing improvement in image quality, thanks to better coil technology, increased speed of acquisition, refinement in respiratory compensation techniques, and newer sequences. Heavily T2-weighted fast spin-echo (FSE) and single-shot FSE MR imaging sequences with long echo times are used to image the biliary and pancreatic ducts.

Visualizing water clearance in the lung with MRI.

Current indirect measurements of alveolar fluid clearance (AFC) suggest that the rate of fluid clearance correlates with morbidity and mortality in patients with pulmonary edema. In a traditional AFC-measurement, fluid laced with a tracer macromolecule is instilled into the lung and thereafter repeated samples of the instilled fluid are extracted from the lung's fluid-filled airspaces. The change in concentration of the tracer molecule indicates the AFC-rate.

Late gadolinium enhancement of the right ventricular myocardium: is it really different from the left ?

It has been suggested that, in late gadolinium enhancement, the signal of right ventricular myocardium is nulled at a shorter inversion time than the left. While we initially made the same observation, we believe that the difference is not real, but results from artifacts. We present 7 cases as well as computer simulations to describe the nature of these artifacts and explain how they can create the impression of different inversion times for the right and left ventricle.