An important image processing step in spinal cord magnetic resonance imaging is the ability to reliably and accurately segment grey and white matter for tissue specific analysis. There are several semi- or fully-automated segmentation methods for cervical cord cross-sectional area measurement with an excellent performance close or equal to the manual segmentation. However, grey matter segmentation is still challenging due to small cross-sectional size and shape, and active research is being conducted by several groups around the world in this field. Therefore a grey matter spinal cord segmentation challenge was organised to test different capabilities of various methods using the same multi-centre and multi-vendor dataset acquired with distinct 3D gradient-echo sequences. This challenge aimed to characterize the state-of-the-art in the field as well as identifying new opportunities for future improvements. Six different spinal cord grey matter segmentation methods developed independently by various research groups across the world and their performance were compared to manual segmentation outcomes, the present gold-standard. All algorithms provided good overall results for detecting the grey matter butterfly, albeit with variable performance in certain quality-of-segmentation metrics. The data have been made publicly available and the challenge web site remains open to new submissions. No modifications were introduced to any of the presented methods as a result of this challenge for the purposes of this publication.

Respiration correction in the spinal cord is necessary to accurately quantify APT CEST, which can provide unique biochemical information regarding disease processes within the spinal cord. Magn Reson Med 79:806-814, 2018. © 2017 International Society for Magnetic Resonance in Medicine.

Background The clinical course of MS is mainly attributable to cervical and upper thoracic spinal cord dysfunction. High-resolution, 7T anatomical imaging of the cervical spinal cord is presented. Image contrast between gray/white matter and lesions surpasses conventional, clinical T1- and T2-weighted sequences at lower field strengths. Objective To study the spinal cord of healthy controls and patients with MS using magnetic resonance imaging at 7T. Methods Axial (C2-C5) T1- and T2*-weighted and sagittal T2*-/spin-density-weighted images were acquired at 7T in 13 healthy volunteers (age 22-40 years), and 15 clinically diagnosed MS patients (age 19-53 years, EDSS 0-3) in addition to clinical 3T scans. In healthy volunteers, a high-resolution multi-echo gradient echo scan was obtained over the same geometry at both fields. Evaluation included signal and contrast to noise ratios and lesion counts for healthy and patient volunteers, respectively. Results/Conclusion High-resolution images at 7T exceeded resolutions reported at lower field strengths. Gray and white matter were sharply demarcated and MS lesions were more readily visualized at 7T compared to clinical acquisitions. with lesions apparent at both fields. Nerve roots were clearly visualized. White matter lesion counts averaged 4.7 vs. 3.1 (52% increase) per patient at 7T vs. 3T, respectively (p = 0.05).

Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. MethodsWe did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung's disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. FindingsWe included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung's disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58•0%) were male. Median gestational age at birth was 38 weeks (IQR 36-39) and median bodyweight at presentation was 2•8 kg (2•3-3•3). Mortality among all patients was 37 (39•8%) of 93 in low-income countries, 583 (20•4%) of 2860 in middle-income countries, and 50 (5•6%) of 896 in high-income countries (p<0•0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90•0%] of ten in lowincome countries, 97 [31•9%] of 304 in middle-income countries, and two [1•4%] of 139 in high-income countries; p≤0•0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2•78 [95% CI 1•88-4•11], p<0•0001; middle-income vs high-income countries, 2•11 [1•59-2•79], p<0•0001), sepsis at presentation (1•20 [1•04-1•40], p=0•016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4-5 vs ASA 1-2, 1•82 [1•40-2•35], p<0•0001; ASA 3 vs ASA 1-2, 1•58, [1•30-1•92], p<0•0001]), surgical safety checklist not used (1•39 [1•02-1•90], p=0•035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1•96, [1•4...

Glutamate-sensitive contrast was significantly increased in the prefrontal cortex of MS patients with accumulated disability ( p < 0.05). In addition, glutamate-sensitive contrast in the prefrontal cortex was significantly correlated with symbol digit modality test ( r = -0.814) and choice reaction time ( r = 0.772) scores in patients ( p < 0.05), suggesting that GluCEST MRI may have utility as a marker for GM pathology and CI.

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BackgroundOptic neuritis (ON) is one of the most common presentations of multiple sclerosis (MS). Magnetic resonance imaging (MRI) of the optic nerves is challenging because of retrobulbar motion, orbital fat and susceptibility artifacts from maxillary sinuses; therefore, axonal loss is investigated with the surrogate measure of a single heuristically defined point along the nerve as opposed to volumetric investigation.ObjectiveThe objective of this paper is to derive optic nerve volumetrics along the entire nerve length in patients with MS and healthy controls in vivo using high-resolution, clinically viable MRI.MethodsAn advanced, isotropic T2-weighted turbo spin echo MRI was applied to 29 MS patients with (14 patients ON+) or without (15 patients ON–) history of ON and 42 healthy volunteers. An automated tool was used to estimate and compare whole optic nerve and surrounding cerebrospinal fluid radii along the length of the nerve.Results and conclusionOnly ON+ MS patients had a significantly reduced optic nerve radius compared to healthy controls in the central segment of the optic nerve. Using clinically available MRI methods, we show and quantify ON volume loss for the first time in MS patients.

Spinal cord (SC) damage is linked to clinical deficits in patients with multiple sclerosis (MS), however, conventional MRI methods are not specific to the underlying macromolecular tissue changes that may precede overt lesion detection. Single-point quantitative magnetization transfer (qMT) is a method that can provide high-resolution indices sensitive to underlying macromolecular composition in a clinically feasible scan time by reducing the number of MT-weighted acquisitions and utilizing a two-pool model constrained by empirically determined constants. As the single-point qMT method relies on a priori constraints, it has not been employed extensively in patients, where these constraints may vary, and thus, the biases inherent in this model have not been evaluated in a patient cohort. We, therefore, addressed the potential biases in the single point qMT model by acquiring qMT measurements in the cervical SC in patient and control cohorts and evaluated the differences between the control and patient-derived qMT constraints (kmf, T2fR1f, and T2m) for the single point model. We determined that the macromolecular to free pool size ratio (PSR) differences between the control and patient-derived constraints are not significant (p > 0.149 in all cases). Additionally, the derived PSR for each cohort was compared, and we reported that the white matter PSR in healthy volunteers is significantly different from lesions (p < 0.005) and normal appearing white matter (p < 0.02) in all cases. The single point qMT method is thus a valuable method to quantitatively estimate white matter pathology in MS in a clinically feasible scan time.