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This paper describes a method for building interpolating or approximating implicit surfaces from polygonal data. The user can choose to generate a surface that exactly interpolates the polygons, or a surface that approximates the input by smoothing away features smaller than some user-specified size. The implicit functions are represented using a moving least-squares formulation with constraints integrated over the polygons. The paper also presents an improved method for enforcing normal constraints and an iterative procedure for ensuring that the implicit surface tightly encloses the input vertices.

Background: Canada began a national reform of its post-graduate medical education training programs to a Competence By Design (CBD) model. Trends from accredited neuroradiology programs from the past 10 years were investigated to inform educators and stakeholders for this process., Methods: A 13-question electronic survey was sent to program directors of all 8 accredited neuroradiology training programs in Canada. Data was requested for each year on the 2008-2019 graduating classes. Questions pertained to program enrolment; program completion; post-training employment; and the sufficiency of 1-year training programs., Results: Response rate was 100%. Over the timeframe studied, the 2-year programs increased in size ( P = 0.007), while the 1-year programs remained steady ( P = 0.27). 12.2% of trainees enrolled in the 2-year program dropped out after 1 year, and were considered 1-year trainees thereafter. A higher proportion of 2-year trainees obtain positions within academic institutions (89.5 vs 67.2%, P = 0.0007), whereas a higher proportion of 1-year trainees obtain positions within non-academic institutions (29.3 vs 8.1%, P = 0.0007). A higher proportion of those with Canadian board certification in diagnostic radiology who completed a 2-year program obtained a position within a Canadian academic institution compared to non-certified 2-year trainees ( P < 0.001). 71.4% of program directors agreed that a 1-year program was sufficient for non-academic staff positions., Conclusion: The length of the training program has significant impact on employment in academic vs non-academic institutions. This information can be used to guide the upcoming CBD initiative for neuroradiology programs.

The objectives of this study were to (a) develop a standing MRI imaging protocol, tolerable to symptomatic patients with degenerative spondylolisthesis (DLS), and (b) to evaluate the morphometric changes observed in DLS patients in both supine and standing postures. Patients with single level, Meyerding grade 1 DLS undergoing surgery at a single institution between November 2015 to May 2017 were consented. Patients were imaged in the supine and standing positions in a 0.5 T vertically open MRI scanner (MROpen, Paramed, Genoa, Italy) with sagittal and axial T2 images. The morphometric parameters measured were: cross-sectional area of the thecal sac (CSA), lateral recess height, disc height, degree of anterolisthesis, disc angle, lumbar lordosis, the presence of facet effusion and restabilization signs. Measures from both postures were compared using paired T-test. Associations of posture with the magnitude of change in the various measurements was determined using Pearson correlation or paired T-test when appropriate. All fourteen patients (mean age 64.4 years) included tolerated standing for the time required for image acquisition. All measurements with the exception of lumbar lordosis and disk height showed a statistically significant difference between the postures (p < 0.05). In the standing position, CSA and lateral recess height were reduced by 28% and 50%, respectively. There was no relationship between the change in CSA of the thecal sac and any measures. Standing images acquired in an upright MRI scanner demonstrated postural changes associated with Meyerding grade 1 DLS and images acquisition was tolerated in all patients., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Competing Interests: Competing interests: None declared.

Purpose: To assess the effect of upright, seated, and supine postures on lumbar muscle morphometry at multiple spinal levels and for multiple muscles., Methods: Six asymptomatic volunteers were imaged (0.5 T upright open MRI) in 7 postures (standing, standing holding 8 kg, standing 45° flexion, seated 45° flexion, seated upright, seated 45° extension, and supine), with scans at L3/L4, L4/L5, and L5/S1. Muscle cross-sectional area (CSA) and muscle position with respect to the vertebral body centroid (radius and angle) were measured for the multifidus/erector spinae combined and psoas major muscles., Results: Posture significantly affected the multifidus/erector spinae CSA with decreasing CSA from straight postures (standing and supine) to seated and flexed postures (up to 19%). Psoas major CSA significantly varied with vertebral level with opposite trends due to posture at L3/L4 (increasing CSA, up to 36%) and L5/S1 (decreasing CSA, up to 40%) with sitting/flexion. For both muscle groups, radius and angle followed similar trends with decreasing radius (up to 5%) and increasing angle (up to 12%) with seated/flexed postures. CSA and lumbar lordosis had some correlation (multifidus/erector spinae L4/L5 and L5/S1, r = 0.37-0.45; PS L3/L4 left, r =  - 0.51). There was generally good repeatability (average ICC(3, 1): posture = 0.81, intra = 0.89, inter = 0.82)., Conclusion: Changes in multifidus/erector spinae muscle CSA likely represent muscles stretching between upright and seated/flexed postures. For the psoas major, the differential level effect suggests that changing three-dimensional muscle morphometry with flexion is not uniform along the muscle length. The muscle and spinal level-dependent effects of posture and spinal curvature correlation, including muscle CSA and position, highlight considering measured muscle morphometry from different postures in spine models.

Standardized magnetic resonance imaging (MRI) protocols are important for the diagnosis and monitoring of patients with multiple sclerosis (MS). The Consortium of Multiple Sclerosis Centers (CMSC) convened an international panel of MRI experts to review and update the current guidelines. The objective was to update the standardized MRI protocol and clinical guidelines for diagnosis and follow-up of MS and develop strategies for advocacy, dissemination, and implementation. Conference attendees included neurologists, radiologists, technologists, and imaging scientists with expertise in MS. Representatives from the CMSC, Magnetic Resonance Imaging in MS (MAGNIMS), North American Imaging in Multiple Sclerosis Cooperative, US Department of Veteran Affairs, National Multiple Sclerosis Society, Multiple Sclerosis Association of America, MRI manufacturers, and commercial image analysis companies were present. Before the meeting, CMSC members were surveyed about standardized MRI protocols, gadolinium use, need for diffusion-weighted imaging, and the central vein sign. The panel worked to make the CMSC and MAGNIMS MRI protocols similar so that the updated guidelines could ultimately be accepted by international consensus. Advocacy efforts will promote the importance of standardized MS MRI protocols. Dissemination will include publications, meeting abstracts, educational programming, webinars, "meet the expert" teleconferences, and examination cards. Implementation will require comprehensive and coordinated efforts to make the protocol easy to access and use. The ultimate vision, and goal, is for the guidelines to be universally useful, usable, and used as the standard of care for patients with MS., Competing Interests: Financial Disclosures: Dr Li has received grant/research support from the Multiple Sclerosis Society of Canada; is a consultant for Biogen, EMD Serono, Genzyme, Novartis, Nuron Biotech, Opexa, and Vertex Pharmaceuticals; is on the speakers’ bureaus for Genzyme, Novartis, and the CMSC; and is emeritus director of The University of British Columbia MS/MRI Research Group, which has been contracted to perform central analysis of MRIs for therapeutic trials with Chugai, Genzyme, Hoffmann-LaRoche, EMD Serono, Nuron Biotech, Perceptive Analytics, and Sanofi Aventis. Dr Banwell is a consultant for Novartis, UCB, and Roche Pharmaceuticals; has served as a nonremunerated advisor to Biogen and Teva Neuroscience; and receives grant funding from the NMSS, Multiple Sclerosis Society of Canada, and National Institutes of Health. Dr Barkhof reports financial relationships with Neurology, Brain, Radiology, Multiple Sclerosis Journal, and Neuroradiology Journal; personal fees from Springer, Biogen, Roche, IXICO Ltd, and Combinostics; personal fees and other from Bayer and GeNeuro; grants from Novartis, Teva Pharmaceutical, Merck, Biogen, IMI-EU, GE Healthcare, UK Multiple Sclerosis Society, Dutch MS Research Foundation, NWO, and the National Institute for Health Research. Dr Dunn holds a patent (USPTO # 10054588) for biomarker of MS treatment responsiveness; has ownership interest in Scientific Advisory Board and Progentec Diagnostics Inc; and received honoraria for consulting or lectures from Bristol Myers Squibb, Alexion, Novartis, Genzyme, and Roche Genentech. Dr Giri is an employee of Siemens Healthineers. Ms Maes is an employee of CorTechs Labs Inc. Dr Newsome receives consulting fees for scientific and board meetings from Biogen, Genentech, Celgene, EMD Serono, and Novartis; is an advisor for BioIncept and Autobahn Therapeutics; is a clinical adjudication committee member for a MedDay trial; and received research funding (paid directly to institution) from Biogen, Genentech, NMSS, Department of Defense, and Patient-Centered Outcomes Research Institute. Dr Paul receives honoraria for lecturing and travel expenses for attending meetings from Guthy-Jackson Charitable Foundation, Sanofi Genzyme, Novartis, Alexion, Viela Bio, Roche, UCB, Mitsubishi Tanabe, and Celgene, and his research is funded by the German Ministry for Education and Research, Deutsche Forschungsgemeinschaft, Einstein Foundation, Guthy-Jackson Charitable Foundation, EU FP7 Framework Program, Arthur Arnstein Foundation Berlin, Biogen, Genzyme, Merck Serono, Novartis, Bayer, Teva Pharmaceutical, Alexion, Roche Parexel, and Almirall. Mr Quarterman is an employee of GE Healthcare. Dr Reich receives personal fees from Bounds Law Group LLC and Leventhal and Puga LLC and has a patent on system and method of automatically detecting tissue abnormalities (US Patent 9,607,392) issued, a patent on method of analyzing multisequence MRI data for analyzing brain abnormalities in a subject (US Patent 9,888,876) issued, a patent on automatic identification of subjects at risk of MS (US Patent application 16/254,710) pending, and a patent on high-resolution cerebrospinal fluid–suppressed T2*- weighted MRI of cortical lesions (US Patent application 62/838,578) pending. Dr Shinohara receives consulting fees from the American Medical Association/Emerson Collective for reviewership duties. Dr Van Hecke has ownership interest in icometrix. Dr van de Ven is an employee of Philips Healthcare. Dr Wallin has received grant funding from the NMSS, the VA Merit Review grant system, and Genentech; is a consultant for the RAND Corporation, the Centers for Disease Control and Prevention, and the Multiple Sclerosis International Federation. Dr Wolinsky receives royalties for out-licensed monoclonal antibodies through University of Texas Health from Millipore Corp; is the intellectual property rights/patent holder of US010363245B2 (Methods for Treating CNS Lesions/Board of Regents UT System); and receives consulting fees from Alkermes, Brainstorm Cell Therapeutics, EMD Serono, GW Pharmaceuticals, MedDay, NervGen, Novartis, Roche/Genentech, and Sanofi Genzyme. Dr Traboulsee receives consulting fees from Genzyme, Roche, and Novartis; is on the speakers’ bureaus for Genzyme and Roche; and is the principal investigator (contracted research) for clinical trials with Genzyme and Roche. The other authors declare no conflicts of interest., (© 2020 Consortium of Multiple Sclerosis Centers.)

Objective: MRI derived spinal-muscle morphology measurements have potential diagnostic, prognostic, and therapeutic applications in spinal health. Muscle morphology in the thoracic spine is an important determinant of kyphosis severity in older adults. However, the literature on quantification of spinal muscles to date has been limited to cervical and lumbar regions. Hence, we aim to propose a method to quantitatively identify regions of interest of thoracic spinal muscle in axial MR images and investigate the repeatability of their measurements., Methods: Middle (T4-T5) and lower (T8-T9) thoracic levels of six healthy volunteers (age 26 ± 6 years) were imaged in an upright open scanner (0.5T MROpen, Paramed, Genoa, Italy). A descriptive methodology for defining the regions of interest of trapezius, erector spinae, and transversospinalis in axial MR images was developed. The guidelines for segmentation are laid out based on the points of origin and insertion, probable size, shape, and the position of the muscle groups relative to other recognizable anatomical landmarks as seen from typical axial MR images. 2D parameters such as muscle cross-sectional area (CSA) and muscle position (radius and angle) with respect to the vertebral body centroid were computed and 3D muscle geometries were generated. Intra and inter-rater segmentation repeatability was assessed with intraclass correlation coefficient (ICC (3,1)) for 2D parameters and with dice coefficient (DC) for 3D parameters., Results: Intra and inter-rater repeatability for 2D and 3D parameters for all muscles was generally good/excellent (average ICC (3,1) = 0.9 with ranges of 0.56-0.98; average DC = 0.92 with ranges from 0.85-0.95)., Conclusion: The guidelines proposed are important for reliable MRI-based measurements and allow meaningful comparisons of muscle morphometry in the thoracic spine across different studies globally. Good segmentation repeatability suggests we can further investigate the effect of posture and spinal curvature on muscle morphology in the thoracic spine., Competing Interests: The authors declare that they have no conflict of interest., (© 2020 The Authors. JOR Spine published by Wiley Periodicals LLC on behalf of Orthopaedic Research Society.)

Dural carotid cavernous fistulas are usually treated via a transvenous approach through the inferior petrosal sinus. Surgical exposure and direct access to the superior ophthalmic vein have been previously described in situations in which conventional transvenous access, including the inferior petrosal sinus, is not possible. In this retrospective study of 20 patients, we report our results of imaging-guided percutaneous superior ophthalmic vein access in dural carotid cavernous fistula treatment. The superior ophthalmic vein was accessed after direct percutaneous puncture under sonographic guidance in 16 patients and biplane roadmap guidance in 4 patients. In all 20 patients, it was possible to access the superior ophthalmic vein and cure the dural carotid cavernous fistula. Two patients developed a retrobulbar hematoma after postseptal puncture, which required emergency lateral canthothomy. In our experience, direct imaging-guided percutaneous superior ophthalmic vein access is a safe alternative approach for treatment in situations in which conventional transvenous approaches are not possible., (© 2019 by American Journal of Neuroradiology.)

Background and Purpose: Hemi-laryngopharyngeal spasm is a recently discovered condition characterized by episodic coughing and unilateral throat contractions that may lead to severe stridor. These symptoms are caused by a vascular compression of the ipsilateral vagus nerve, typically the PICA. Microvascular decompression of the vagus nerve has been demonstrated to be a potential cure for this neurovascular compression syndrome. The main aim of this study was to clarify the role of MR imaging in the diagnostic work-up of this rare condition., Materials and Methods: We describe the imaging and surgical findings of 3 patients from our prospective case series of patients with hemi-laryngopharyngeal spasm from 2015 to 2017. Second, the imaging data of 100 patients (control cohort) with symptoms unrelated to hemi-laryngopharyngeal spasm were reviewed to investigate the rate and degree of neurovascular conflict of the vagus nerve., Results: All patients with hemi-laryngopharyngeal spasm reported to date have had vascular compression of the vagus nerve due to the PICA. In the control cohort, there was a good interrater agreement in scoring the "contact" and "compression" of the vagus nerve (κ = 0.73. P = < .001). The frequency of contact or compression of the vagus nerve was approximately 50%. The PICA was the most frequent vessel involved in 74%., Conclusions: The presence of unilateral neurovascular contact or compression of the vagus nerve does not confirm the diagnosis of hemi-laryngopharyngeal spasm. The MR imaging finding of ipsilateral vascular compression of the vagus nerve is a necessary but not sufficient finding for the diagnosis of hemi-laryngopharyngeal spasm., (© 2018 by American Journal of Neuroradiology.)

Emerging evidence has confirmed that, following administration of a gadolinium-based contrast agent (GBCA), very small amounts of gadolinium will deposit in the brain of humans with intact blood-brain barriers. The literature is evolving rapidly and the degree to which gadolinium will deposit for a particular GBCA or class of GBCAs remains undetermined. Several studies suggest that linear GBCAs deposit more gadolinium in the brain compared with macrocyclic GBCAs; however, our understanding of the molecular composition of deposited gadolinium is preliminary, and the clinical significance of gadolinium deposition remains unknown. To date, there is no conclusive evidence linking gadolinium deposition in the brain with any adverse patient outcome. A panel of radiologists representing the Canadian Association of Radiologists was assembled to assist the Canadian medical imaging community in making informed decisions regarding the issue of gadolinium deposition in the brain. The objectives of the working group were: 1) to review the evidence from animal and human studies; 2) to systematically review existing guidelines and position statements issued by other organizations and health agencies; and 3) to formulate an evidence-based position statement on behalf of the Canadian Association of Radiologists. Based on our appraisal of the evidence and systematic review of 9 guidelines issued by other organizations, the working group established the following consensus statement. GBCA administration should be considered carefully with respect to potential risks and benefits, and only used when required. Standard dosing should be used and repeat administrations should be avoided unless necessary. Gadolinium deposition is one of several issues to consider when prescribing a particular GBCA. Currently there is insufficient evidence to recommend one class of GBCA over another. The panel considered it inappropriate to withhold a linear GBCA if a macrocyclic agent is unavailable, if hepatobiliary phase imaging is required, or if there is a history of severe allergic reaction to a macrocyclic GBCA. Further study in this area is required, and the evidence should be monitored regularly with policy statements updated accordingly., (Copyright © 2018 Canadian Association of Radiologists. Published by Elsevier Inc. All rights reserved.)

Reversible cerebral vasoconstriction syndrome is an intracranial vascular manifestation of a wide variety of diseases. It is the second most common cause of thunderclap headache, the most common cause of recurrent severe secondary headaches, and, in patients <60 years of age, has been reported as the commonest cause of isolated convexity subarachnoid haemorrhage. Radiologically, its key feature is vasoconstriction of the intracranial vessels, a dynamic process that is typically maximal at 2 weeks, varies in its distribution over the course of the disease, and typically resolves after 3 months. It can have haemorrhagic and ischaemic complications and sometimes occurs in concert with posterior reversible encephalopathy syndrome. It also has important associations with dissection and migraine. Rarer atypical cases can present with mild headache, no headache at all, or even a comatose state. This paper provides a detailed review of this syndrome, its pathophysiology, differential diagnosis, imaging findings, and work-up. It also describes the role that high-resolution magnetic resonance imaging (MRI) techniques can have in diagnosing the disease and emphasises the central role that all radiologists have in detecting this important and underdiagnosed condition., (Copyright © 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

The interaction between fungi and the sinonasal tract results in a range of clinical presentations with a broad spectrum of clinical severity. The most commonly accepted classification system divides fungal rhinosinusitis into invasive and noninvasive subtypes based on histopathological evidence of tissue invasion by fungi. Invasive fungal rhinosinusitis is subdivided into acute invasive and chronic invasive categories. The chronic invasive category includes a subcategory of chronic granulomatous disease. Noninvasive fungal disease includes localized fungal colonization, fungal ball, and allergic fungal rhinosinusitis. Noninvasive disease is simply fungal material (or the products of the inflammatory reaction of the sinus mucosa) that fills the sinuses but does not invade tissue. Bone loss is related to expansion of the sinus(es). Invasive disease causes tissue destruction, such that it expands past the bony confines of the sinuses. It can rapidly spread, causing acute necrosis. Alternatively, there may be slow tissue invasion characterized by symptoms confused with normal sinusitis, but destruction of normal nasal and paranasal structures., (Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.)

Objectives: To examine the effect of pre-injury alcohol use, acute alcohol intoxication, and post-injury alcohol use on outcome from mild to moderate traumatic brain injury (TBI)., Methods: Prospective inception cohort of patients who presented to the Emergency Department with mild to moderate TBI and had a blood alcohol level (BAL) taken for clinical purposes. Those who completed the 1-year outcome assessment were eligible for this study (N=91). Outcomes of interest were the count of post-concussion symptoms (British Columbia Post-Concussion Symptom Inventory), low neuropsychological test scores (Neuropsychological Assessment Battery), and abnormal regions of interest on diffusion tensor imaging (low fractional anisotropy). The main predictors were pre-injury alcohol consumption (Cognitive Lifetime Drinking History interview), BAL, and post-injury alcohol use., Results: The alcohol use variables were moderately to strongly inter-correlated. None of the alcohol use variables (whether continuous or categorical) were related to 1-year TBI outcomes in generalized linear modeling. Participants in this cohort generally had a good clinical outcome, regardless of their pre-, peri-, and post-injury alcohol use., Conclusions: Alcohol may not significantly alter long-term outcome from mild to moderate TBI. (JINS, 2016, 22, 816-827).

This study examined whether intracranial neuroimaging abnormalities in those with mild traumatic brain injury (MTBI) (i.e., "complicated" MTBIs) are associated with worse subacute outcomes as measured by cognitive testing, symptom ratings, and/or diffusion tensor imaging (DTI). We hypothesized that (i) as a group, participants with complicated MTBIs would report greater symptoms and have worse neurocognitive outcomes than those with uncomplicated MTBI, and (ii) as a group, participants with complicated MTBIs would show more Diffusion Tensor Imaging (DTI) abnormalities. Participants were 62 adults with MTBIs (31 complicated and 31 uncomplicated) who completed neurocognitive testing, symptom ratings, and DTI on a 3T MRI scanner approximately 6-8 weeks post injury. There were no statistically significant differences between groups on symptom ratings or on a broad range of neuropsychological tests. When comparing the groups using tract-based spatial statistics for DTI, no significant difference was found for axial diffusivity or mean diffusivity. However, several brain regions demonstrated increased radial diffusivity (purported to measure myelin integrity), and decreased fractional anisotropy in the complicated group compared with the uncomplicated group. Finally, when we extended the DTI analysis, using a multivariate atlas based approach, to 32 orthopedic trauma controls (TC), the findings did not reveal significantly more areas of abnormal DTI signal in the complicated vs. uncomplicated groups, although both MTBI groups had a greater number of areas with increased radial diffusivity compared with the trauma controls. This study illustrates that macrostructural neuroimaging changes following MTBI are associated with measurable changes in DTI signal. Of note, however, the division of MTBI into complicated and uncomplicated subtypes did not predict worse clinical outcome at 6-8 weeks post injury.

The purpose of this study is to examine the relation between the microstructural architecture of white matter, as measured by diffusion tensor imaging (DTI), and postconcussion symptom reporting 6-8 weeks following mild traumatic brain injury (MTBI). Participants were 108 patients prospectively recruited from a Level 1 Trauma Center (Vancouver, BC, Canada) following an orthopedic injury [i.e., 36 trauma controls (TCs)] or MTBI (n = 72). DTI of the whole brain was undertaken using a Phillips 3T scanner at 6-8 weeks postinjury. Participants also completed a 5 h neurocognitive test battery and a brief battery of self-report measures (e.g., depression, anxiety, and postconcussion symptoms). The MTBI sample was divided into two groups based on ICD-10 criteria for postconcussional syndrome (PCS): first, PCS-present (n = 20) and second, PCS-absent (n = 52). There were no significant differences across the three groups (i.e., TC, PCS-present, and PCS-absent) for any of the neurocognitive measures (p = .138-.810). For the self-report measures, the PCS-present group reported significantly more anxiety and depression symptoms compared with the PCS-absent and TC groups (p < .001, d = 1.63-1.89, very large effect sizes). For the DTI measures, there were no significant differences in fractional anisotropy, axial diffusivity, radial diffusivity, or mean diffusivity when comparing the PCS-present and PCS-absent groups. However, there were significant differences (p < .05) in MD and RD when comparing the PCS-present and TC groups. There were significant differences in white matter between TC subjects and the PCS-present MTBI group, but not the PCS-absent MTBI group. Within the MTBI group, white-matter changes were not a significant predictor of ICD-10 PCS., (© The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The purpose of the study was to disentangle the relative contributions of day-of-injury alcohol intoxication and pre-injury alcohol misuse on outcome from TBI. Participants were 142 patients enrolled from a Level 1 Trauma Center (in Vancouver, Canada) following a traumatic brain injury (TBI; 43 uncomplicated mild TBI and 63 complicated mild-severe TBI) or orthopedic injury [36 trauma controls (TC)]. At 6-8 weeks post-injury, diffusion tensor imaging (DTI) of the whole brain was undertaken using a Phillips 3T scanner. Participants also completed neuropsychological testing, an evaluation of lifetime alcohol consumption (LAC), and had blood alcohol levels (BALs) taken at the time of injury. Participants in the uncomplicated mild TBI and complicated mild-severe TBI groups had higher scores on measures of depression and postconcussion symptoms (d = 0.45-0.83), but not anxiety, compared with the TC group. The complicated mild-severe TBI group had more areas of abnormal white matter on DTI measures (all p < .05; d = 0.54-0.61) than the TC group. There were no difference between groups on all neurocognitive measures. Using hierarchical regression analyses and generalized linear modeling, LAC and BAL did provide a unique contribution toward the prediction of attention and executive functioning abilities; however, the variance accounted for was small. LAC and BAL did not provide a unique and meaningful contribution toward the prediction of self-reported symptoms, DTI measures, or the majority of neurocognitive measures. In this study, BAL and LAC were not predictive of mental health symptoms, postconcussion symptoms, cognition, or white-matter changes at 6-8 weeks following TBI., (Published by Oxford University Press 2014. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

White matter hyperintensities (WMHIs) visible on magnetic resonance imaging (MRI) are common in both healthy adults and in those with medical or psychiatric problems. A practical methodological issue for diffusion tensor imaging (DTI) researchers is whether to include, or exclude, participants from a control group who have WMHIs. The aim of this study was to compare the influence of WMHIs on whole-brain DTI in trauma control subjects. Participants were 48 patients (no-WMHIs, n=36; 2+WMHIs, n=12) prospectively recruited from the Emergency Department of Vancouver General Hospital (British Columbia, Canada). Participants completed an MRI brain scan at 6-8 weeks postinjury (mean, 47.3 days; standard deviation [SD], 6.2; range, 39-66). DTI was used to examine the integrity of white matter (WM) in 50 regions of the brain using measures of fractional anisotropy (FA), and mean (MD), radial (RD), and axial (AD) diffusivity. FA values that were >2 SDs below the mean, and MD, RD, and AD values that were >2 SDs above the mean, were classified as "abnormal scores" indicative of reduced WM integrity. In the entire sample, the 2+WMHI group had a greater number of abnormal FA, MD, and RD scores, compared to the no-WMHI group (p<0.015 and Cohen's d >0.82, indicating large to very large effect sizes, for all comparisons). When controlling for the effects of age using a matched-groups design, the 2+WMHI group still had a significantly greater number of abnormal FA, MD, and RD scores, compared to the no-WMHI group (all p<0.012, all d >0.89, large to very large effect sizes). Researchers should be aware that the inclusion or exclusion of subjects with incidental WMHIs will influence the results of DTI studies.

Background: the term posterior reversible encephalopathy syndrome (PRES) was first proposed in 2000. Since then, the acronym PRES has become very popular in imaging and clinical literature as it is short, easy to say and remember, and neatly couples the frequent localization of neuroimaging findings along with the typical outcome of this syndrome. Another possible reason for the popularity of this acronym in clinical circles is the connotation of PRES with (elevated blood) PRESsure, as a majority of cases are believed to be associated with hypertension. However, problems exist with the interpretation and common understanding of PRES, questioning the appropriateness of "P" and "R" in the acronym. The linguistic issues related to the acronym of PRES are interesting., Objectives: the aim of this work is to analyze the controversies related to the acronym of PRES., Results: in 2006, modifying the meaning of the acronym was suggested, renaming it Potentially Reversible Encephalopathy Syndrome in order to adjust to the cases when posterior involvement is not prominent and emphasize that the reversibility is not spontaneous. This meant the creation of a backronym, where the new phrase is constructed by starting with an existing acronym., Conclusion: this new backronym indicates that the original acronym of PRES has become a misnomer.

Background: Postprimary pulmonary tuberculosis (TB) is not commonly seen in children., Objective: The purpose of this study was to determine the radiographic findings and patient characteristics of pediatric postprimary pulmonary TB., Materials and Methods: We reviewed the clinical charts and chest radiographs in six patients., Results: The radiographic findings of pediatric postprimary pulmonary TB include upper-lobe consolidation and cavitation, multifocal ill-defined airspace opacities, evidence of prior pulmonary TB, and apical pleural thickening. Pleural effusions and lymphadenopathy are not commonly present. Although postprimary disease typically does not affect young children, five of the children in this series were less than ten years of age at the time of presentation., Conclusion: The possibility of postprimary TB should be considered in pediatric patients at risk for this disease who present with upper-lobe pulmonary consolidation and cavitation. These patients are highly infectious and early recognition and treatment can limit transmission of TB.