Prognostic accuracy and impact of cerebral collateral status on clinical and safety outcomes in acute ischemic stroke patients receiving reperfusion therapy: a systematic meta-analysis.

BACKGROUND: Cerebral collateral status has a potential role in mediating postreperfusion clinical and safety outcomes in acute ischemic stroke (AIS). PURPOSE: To investigate the prognostic accuracy and impact of collateral status on clinical and safety outcomes in patients with AIS receiving reperfusion therapy. MATERIAL AND METHODS: Studies with AIS patients treated with reperfusion therapy, collateral status assessed using Tan, ASITN/SIR, or similar collateral grading methods and data stratified according to collateral status were included. Relevant data on clinical outcomes, such as functional outcome at 90 days, mortality at 90 days, angiographic reperfusion, symptomatic intracerebral hemorrhage (sICH) and hemorrhagic transformation (HT), were collated and analyzed. RESULTS: A meta-analysis of 18 studies involving 4132 patients with AIS was conducted. Good collateral status was significantly associated with angiographic reperfusion (odds ratio [OR]=1.97, 95% confidence interval [CI]=1.38-2.80; P < 0.0001), sICH (OR=0.67, 95% CI=0.46-0.99; P = 0.042), and 90-day functional outcome (OR=3.05, 95% CI=1.78-5.24; P < 0.0001). However, its association with HT (OR=0.76, 95% CI=0.38-1.51; P = 0.425) and three-month mortality (OR=0.53, 95% CI=0.17-1.69; P = 0.280) did not reach statistical significance. The prognostic accuracy of collaterals for predicting angiographic reperfusion, HT, functional outcome (at 90 days), and mortality (at 90 days) were 63%, 49%, 66%, and 48%, respectively. CONCLUSION: Cerebral collaterals are significantly associated with clinical and safety outcomes, albeit with a prognostic accuracy range of 48%-66%; thus, evaluation of their patency is a useful prognostic tool in patients with AIS receiving reperfusion therapy.

Greater muscle volume and muscle fat infiltrate in the deep cervical spine extensor muscles (multifidus with semispinalis cervicis) in individuals with chronic idiopathic neck pain compared to age and sex-matched asymptomatic controls: a cross-sectional study.

Muscle size and composition (muscle volume and muscle fat infiltrate [MFI]) may provide insight into possible mechanisms underpinning chronic idiopathic neck pain, a common condition with no definitive underlying pathology. In individuals with chronic idiopathic neck pain > 3 months and age- and sex-matched asymptomatic controls, muscle volumes of levator scapulae, multifidus including semispinalis cervicis (MFSS), semispinalis capitis, splenius capitis including splenius cervicis (SCSC), sternocleidomastoid and longus colli from C3 through T1 were quantified from magnetic resonance imaging. Between-group differences were determined using linear mixed models, accounting for side (left or right), muscle, spinal level, sex, age, and body mass index (BMI). Individuals with pain had greater muscle volume (mean difference 76.8mm3; 95% CI 26.6-127.0; p = .003) and MFI (2.3%; 0.2-4.5; p = .034) of the MFSS compared to matched controls with no differences in relative volume, accounting for factors associated with the outcomes: muscle, spinal level, side (left had smaller volume, relative volume and MFI than right), sex (females had less volume and relative volume than males), age (older age associated with less relative volume and greater MFI), and BMI (higher BMI associated with greater muscle volume and MFI). Greater MFI in individuals with chronic idiopathic neck pain suggests a possible underlying mechanism contributing to neck pain. Perspective: These findings suggest MFI in the MFSS may be radiologic sign, potentially identifying patients with a less favourable prognosis. Future studies are needed to confirm this finding and determine if MFI is a contributor to the development or persistence of neck pain, or consequence of neck pain.

Retinal nerve fibre changes in sports-related repetitive traumatic brain injury.

IMPORTANCE: There is limited literature on the use of optical coherence tomography in the assessment of retinal nerve fibre layer (RNFL) thickness in sports-related repetitive mild traumatic brain injury. BACKGROUND: To evaluate RNFL thickness in professional rugby league players. RNFL thinning may serve as a proxy for wider white matter degeneration. DESIGN: Cross-sectional observational study. PARTICIPANTS: Thirteen retired Australian professional rugby league players were recruited. METHODS: Participants underwent binocular optical coherence tomography to measure RNFL thickness. Each participant underwent a complete ophthalmic assessment to exclude concurrent disease. MAIN OUTCOME MEASURES: RNFL thickness of each eye were compared with a normative database. RESULTS: Participants had played professional Rugby League for 18 years on average and reported sustaining 15 sports-related concussions throughout their career. The RNFL in participants was four micrometres thinner than that of matched normative data. Cohort average RNFL thickness was reduced in 12 out of 14 optical coherence testing parameters. These findings were statistically significant in the left inferonasal [P = .013] and left nasal [P = .006] sectors. There was no statistically significant relationship between RNFL thickness and other visual measures. CONCLUSIONS AND RELEVANCE: This study is the first to demonstrate RNFL thinning in a cohort of retired Australian professional Rugby League players. RNFL changes have been shown to correlate with cerebral white matter loss and neurodegeneration. Optical coherence tomography may serve as a safe and economical means of screening for repetitive traumatic brain injury related neurodegeneration in contact sport athletes.

Food addiction linked to changes in ventral striatum functional connectivity between fasting and satiety.

INTRODUCTION: The concept of "food addiction" (FA) has gained popularity in view of clinical and neurobiological overlaps between excessive food intake and addictive disorders. However, no studies have examined the link between FA and striatocortical circuits involved in addictive disorders, or the influence of homeostatic status, which regulates the drive to eat, on these systems. This study aims to investigate changes in striatal functional connectivity between fasted and fed conditions among adults ranging in body mass index (BMI) and FA symptoms. METHODS: Thirty adults were recruited from the general community and completed self-reported surveys including demographics, FA symptoms using the Yale Food Addiction Scale, as well as height and weight measures, used to determine BMI. Participants completed two 3-T MRI scans, one in a fasted state and one in a fed state. We conducted seed-based analyses to examine between-session ("fasted > fed") change in resting-state functional connectivity of the ventral and dorsal striatum, and its association with FA scores (controlling for BMI). RESULTS: Higher symptoms of FA correlated with greater changes in ventral caudate-hippocampus connectivity between fasted and fed conditions. FA symptoms did not correlate with connectivity in the dorsal caudate circuit. Post-hoc analyses revealed that participants with higher symptoms of FA had ventral caudate-hippocampus hyperconnectivity in the fasted scan only, as well as a significant reduction of this connectivity between the fasted and fed scans. CONCLUSIONS: Heightened connectivity in the ventral striatum during a fasted state, which has been linked to reward prediction signals, underpins symptoms of FA. In contrast, connectivity in the dorsal striatum or "habit" system is unrelated to homeostatic status and FA symptoms, and is thus less relevant for subclinical manifestations of FA.

Quantitative magnetic resonance imaging assessment of lateral atlantoaxial joint meniscoid composition: a validation study.

PURPOSE: Lateral atlantoaxial (LAA) joint meniscoid composition may have clinical significance in patients following neck trauma. However, the existing method of radiologically assessing meniscoid composition has an inherent element of subjectivity, which could contribute to measurement variability. The present study sought to investigate the accuracy of two-point Dixon fat/water separation MRI as a quantitative assessment of LAA joint meniscoid composition. METHODS: Sixteen LAA joint meniscoids were excised from four cadavers (mean [SD] age 79.5 [3.7] years; one female) following cervical spine MRI (two-point Dixon, T1-weighted VIBE and T2-weighted SPACE sequences). Composition of LAA joint meniscoids was undertaken by (1) histological examination by light microscopy, (2) calculation of fat fraction by Dixon MRI (both in-phase/opposed-phase and fat/water methods), and (3) the existing method of considering VIBE and SPACE signal intensities. Analysis was performed using the kappa statistic with linear weighting. RESULTS: Microscopy revealed three, five, and eight meniscoids to be composed of adipose, fibroadipose, and fibrous tissues, respectively. Dixon sequence MRI classified 11 of these meniscoids correctly, with 'substantial' level of agreement (In-phase/Opp-phase kappa statistic = 0.78 [95% CI 0.38, 1.17]; fat/water kappa statistic = 0.72 [95% CI 0.32, 1.11]). Level of agreement between microscopy and the VIBE and SPACE method was 'slight' (kappa statistic = 0.02 [95% CI - 0.34, 0.38]). CONCLUSIONS: Findings suggest that Dixon fat/water separation MRI may have superior utility in the assessment of LAA joint meniscoid composition than the existing method of considering VIBE and SPACE signal intensities. These slides can be retrieved under Electronic Supplementary Material.

Reperfusion therapy in acute ischemic stroke: dawn of a new era?

Following the success of recent endovascular trials, endovascular therapy has emerged as an exciting addition to the arsenal of clinical management of patients with acute ischemic stroke (AIS). In this paper, we present an extensive overview of intravenous and endovascular reperfusion strategies, recent advances in AIS neurointervention, limitations of various treatment paradigms, and provide insights on imaging-guided reperfusion therapies. A roadmap for imaging guided reperfusion treatment workflow in AIS is also proposed. Both systemic thrombolysis and endovascular treatment have been incorporated into the standard of care in stroke therapy. Further research on advanced imaging-based approaches to select appropriate patients, may widen the time-window for patient selection and would contribute immensely to early thrombolytic strategies, better recanalization rates, and improved clinical outcomes.

MR Spectroscopy Findings in Retired Professional Rugby League Players.

The aim of this study was to examine brain neurometabolite concentrations in retired rugby league players who had a history of numerous self-reported concussions. Participants were 16 retired professional rugby league players (ages 30-45 years) with an extensive history of concussion and participation in contact sports, and 16 age- and education-matched controls who had no history of neurotrauma or participation in contact sports. All completed a clinical interview, psychological and cognitive testing, and magnetic resonance spectroscopy (MRS) investigation. MRS voxels were placed in posterior cingulate grey matter and parietal white matter. Neurometabolite concentrations were quantified using LCModel. It was hypothesized that retired athletes would differ on N-acetyl aspartate, myo-inositol, choline, glutamate, and glutathione. Retired players had significantly lower concentrations of grey matter glutathione (p=0.02, d=0.91). They did not significantly differ in concentrations of other neurometabolites. There were no significant differences between groups on measures of depression, anxiety, or cognitive functioning. The retired athletes reported significantly greater alcohol use (p<0.01; Cohen's d=1.49), and they had worse manual dexterity using their non-dominant hand (p=0.03; d=1.08). These preliminary findings suggest that MRS might be modestly sensitive to biochemical differences in athletes after their athletic careers have ended in the absence of clinical differences in cognitive performance and self-reported psychological functioning.

The influence of initial stroke severity on mortality, overall functional outcome and in-hospital placement at 90 days following acute ischemic stroke: A tertiary hospital stroke register study.

BACKGROUND AND PURPOSE: Epidemiological studies on the extent of the interaction and/or influence of stroke severity on clinical outcomes are important. The aim of the present study was to investigate the putative (and degree of) impact of initial stroke severity in predicting the overall functional outcome, in-hospital placement, and mortality in acute ischemic stroke (AIS) in comparison with age, admission to the stroke unit and thrombolytic treatment. MATERIALS AND METHODS: The John Hunter Hospital acute stroke register was used to collect a retrospective cohort of AIS patients being assessed for reperfusion therapy and admitted between January 2006 and December 2013. Univariate and multivariate logistic regression and receiver operating characteristics analyses were used to assess associations with functional outcome, in-hospital placement, and mortality at 90 days. RESULTS: 608 AIS patients with complete datasets were included in the study. On univariate analysis, initial stroke severity showed the strongest independent association to the risk of death within 90 days (Odds ratio (OR) =1.15; P < 0.001; 95% confidence interval (CI) = [1.11, 1.18]); age was a less significant independent influence (OR = 1.02; P = 0.049; 95% CI = [1.00, 1.03]). Multivariate logistic regression analysis demonstrated that initial stroke severity independently predicted the 90 day mortality (OR = 1.16; 95% CI = [1.12, 1.2]; P < 0.0001) and unfavorable outcome (OR = 1.16; 95% CI = [1.13, 1.2]; P < 0.0001). Higher National Institute of Health Stroke Scale at admission was significantly associated with longer in-hospital placement (P < 0.0001). CONCLUSIONS: In this acute stroke cohort, initial stroke severity had a major impact on the likelihood of death following an AIS and appears to be the dominant influence on the overall stroke outcome and in-hospital placement.

The stability of 'food addiction' as assessed by the Yale Food Addiction Scale in a non-clinical population over 18-months.

The Yale Food Addiction Scale (YFAS) is a widely used tool to assess the behavioural indicators of addictive-like eating. No studies, however, have used a longitudinal design to determine whether these addictive-like eating behaviours are a stable or transient phenomenon in a community-based population. This study aimed to evaluate whether food addiction Diagnosis and Symptom scores as assessed by the YFAS remain stable over 18-months in a non-clinical population. Young adults aged 18-35 years were recruited from the community to a web-based survey in 2013. The survey included demographics, anthropometrics and the YFAS. Participants who volunteered to be recontacted for future research were invited to complete the same survey 18-months later. The YFAS scoring outputs Diagnosis and Symptom scores were tested for agreement and reliability between the two time points. Of the 303 participants who completed the original survey and agreed to be recontacted, 69 participants (22.8% of those recontacted, 94% female, 67% normal weight at baseline) completed the 18-month follow-up survey. At baseline, thirteen participants met the YFAS predefined criteria for Diagnosis, while eleven participants met these criteria at the 18-month follow-up. YFAS Diagnosis was found to have moderate agreement [K = .50, 95% CI (.23, .77)] between the two time points while Symptom scores had good agreement [K = .70, 95% CI (.54, .83)]. Intraclass correlation coefficients were interpreted as moderate over the 18-month period for both the Diagnosis [ICC = .71, 95% CI (.45, .88)] and Symptom scores [ICC = .72, 95% CI (.58, .82)]. YFAS assessed food addiction Diagnosis and Symptom scores were found to be relatively stable over 18-months in a non-clinical population of predominantly female, young adults. Future research is required to determine the impact of behavioural weight loss interventions on YFAS assessed addictive-like eating.

Multiparametric MRI as an outcome predictor for anal canal cancer managed with chemoradiotherapy.

BACKGROUND: Organ-preserving chemo-radiotherapy (CRT) is the standard of care for non-metastatic anal squamous cell carcinoma (SCC). The optimal dosing schedules are yet to be determined. To improve local control rates, dose escalation has been investigated but found to not increase efficacy at the expense of increased toxicity for an unselected patient population. Diffusion weighted imaging (DWI) and dynamic contrast enhanced (DCE) Magnetic Resonance Imaging (MRI) performed during CRT have early data suggesting it to be an effective tool in predicting later tumour response for SCC in related body sites. By performing multi-parametric MRI (mpmMRI) incorporating standard morphological, DWI and DCE sequences, we aim to determine whether the early changes in multi-parametric parameters during CRT can predict for later response in anal SCC. This may create opportunities to investigate treatment adaptation, either intensification or de-escalation, during CRT. METHODS/DESIGN: This protocol describes a prospective non-interventional multi-centre single-arm clinical trial. Twenty eligible patients with histologically confirmed non-metastatic anal SCC will receive standard definitive CRT and undergo multi-parametric MRI's at the following 4 time points; prior to treatment, during the second and fourth weeks of treatment and 6-8 weeks following treatment. Complete response will be defined by the absence of tumour persistence or recurrence as determined by clinical examination at 6 months. Images will be retrospectively analysed to determine the apparent diffusion coefficient and tumour perfusion coefficients (Ktrans and Kep) at each time point. The Mann-Whitney-Wilcoxon Test will be utilised to compare the change in these parameters for responder's verses non-responders. DISCUSSION: If validated, mpmMRI, along with other risk factors, can be used to stratify patients and guide radiation dosing in a prospective trial. Informed individualisation of treatment intensity should help us achieve our goals of improved efficacy and reduced toxicity. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRN12614001219673 (19/11/2014).

A preliminary video analysis of concussion in the National Rugby League.

PRIMARY OBJECTIVE: To conduct the first video analysis of concussion in the Australian National Rugby League (NRL) and describe player and injury characteristics, situational factors and time to return to play. RESEARCH DESIGN: Descriptive, observational case series. METHODS AND PROCEDURES: Video analysis of 20 medically diagnosed concussions for three consenting clubs during the 2013 NRL season. MAIN OUTCOME AND RESULTS: Most concussions (83%) occurred during a high tackle, and all injured ball carriers were hit high. Loss of consciousness was observed in 30% of cases. Common observable signs of injury included clutching of the head, balance problems or wobbly legs and a blank or vacant state. There were no post-concussive seizures. All players with loss of consciousness were removed from play. However, only half of the total sample was removed from play and one athlete who was removed returned to play in the same match. Of the players who were removed from play, the large majority returned the following week. Illegal play accounted for 25% of all concussions. CONCLUSIONS: Video analysis may be a useful method to study the incidence, mechanism and management of concussion in sports such as Rugby League. Future studies may include larger numbers to validate this preliminary data and may also investigate other levels of play and age ranges.

Cerebrovascular reactivity assessed by transcranial Doppler ultrasound in sport-related concussion: a systematic review.

BACKGROUND: Traumatic brain injury influences regulation of cerebral blood flow in animal models and in human studies. We reviewed the use of transcranial Doppler ultrasound (US) to monitor cerebrovascular reactivity following sport-related concussion. REVIEW METHOD: A narrative and systematic review of articles published in the English language, from December 1982 to October 2013. DATA SOURCES: Articles were retrieved via numerous databases using relevant key terms. Observational, cohort, correlational, cross-sectional and longitudinal studies were included. RESULTS: Three publications met the criteria for inclusion; these provided data from 42 athletes and 33 controls. All three studies reported reductions in cerebrovascular reactivity via transcranial Doppler US. CONCLUSIONS: These initial results support the use of cerebrovascular reactivity as a research tool for identifying altered neurophysiology and monitoring recovery in adult athletes. Larger cross-sectional, prospective and longitudinal studies are required to understand the sensitivity and prognostic value of cerebrovascular reactivity in sport-related concussion.

A systematic review of concussion in rugby league.

OBJECTIVES: Concussion remains one of the inherent risks of participation in rugby league. While other injuries incurred by rugby league players have been well studied, less focus and attention has been directed towards concussion. REVIEW METHOD: The current review examined all articles published in English from 1900 up to June 2013 pertaining to concussion in rugby league players. DATA SOURCES: Publications were retrieved via six databases using the key search terms: rugby league, league, football; in combination with injury terms: athletic injuries, concussion, sports concussion, sports-related concussion, brain concussion, brain injury, brain injuries, mild traumatic brain injury, mTBI, traumatic brain injury, TBI, craniocerebral trauma, head injury and brain damage. Observational, cohort, correlational, cross-sectional and longitudinal studies were all included. RESULTS: 199 rugby league injury publications were identified. 39 (20%) were related in some way to concussion. Of the 39 identified articles, 6 (15%) had the main aim of evaluating concussion, while the other 33 reported on concussion incidence as part of overall injury data analyses. Rugby league concussion incidence rates vary widely from 0.0 to 40.0/1000 playing hours, depending on the definition of injury (time loss vs no time loss). The incidence rates vary across match play versus training session, seasons (winter vs summer) and playing position (forwards vs backs). The ball carrier has been found to be at greater risk for injury than tacklers. Concussion accounts for 29% of all injuries associated with illegal play, but only 9% of injuries sustained in legal play. CONCLUSIONS: In comparison with other collision sports, research evaluating concussion in rugby league is limited. With such limited published rugby league data, there are many aspects of concussion that require attention, and future research may be directed towards these unanswered questions.

Investigation on the performance of dedicated radiotherapy positioning devices for MR scanning for prostate planning.

The purpose of this study was to investigate performance of the couch and coil mounts designed for MR-simulation prostate scanning using data from ten volunteers. Volunteers were scanned using the standard MR scanning protocol with the MR coil directly strapped on the external body and the volunteer lying on the original scanner table. They also were scanned using a MR-simulation table top and pelvic coil mounts. MR images from both setups were compared in terms of body contour variation and image quality effects within particular organs of interest. Six-field conformal plans were generated on the two images with assigned bulk density for dose calculation. With the MR-simulation devices, the anterior skin deformation was reduced by up to 1.7 cm. The hard tabletop minimizes the posterior body deformation which can be up to 2.3 cm on the standard table, depending on the weight of volunteer. The image signal-to-noise ratio reduced by 14% and 25% on large field of view (FOV) and small FOV images, respectively, after using the coil mount; the prostate volume contoured on two images showed difference of 1.05 ± 0.66 cm3. The external body deformation caused a mean dose reduction of 0.6 ± 0.3 Gy, while the coverage reduced by 22% ± 13% and 27% ± 6% in V98 and V100, respectively. A dedicated MR simulation setup for prostate radiotherapy is essential to ensure the agreement between planning anatomy and treatment anatomy. The image signal was reduced after applying the coil mount, but no significant effect was found on prostate contouring.

Arterial spin labeling versus bolus-tracking perfusion in hyperacute stroke.

BACKGROUND AND PURPOSE: Arterial spin labeling (ASL) is a perfusion magnetic resonance imaging (MRI) technique that does not require contrast administration and thus may be more practical in hyperacute stroke than susceptibility-weighted bolus-tracking perfusion-weighted imaging (PWI). However, a threshold for ASL measurement of the ischemic penumbra needs to be determined. METHODS: A total of 58 patients with acute hemispheric ischemic stroke were imaged within 6 hours of symptom onset with MRI including ASL, diffusion-weighted MRI (DWI), and PWI, after perfusion computed tomography (CTP). Patients had repeat MRI at 24 hours. On repeat imaging, 32 patients did not reperfuse and were used to determine the penumbra threshold. A receiver-operating curve and a volumetric analysis were undertaken to identify the ASL-cerebral blood flow (CBF) threshold for the acute penumbra compared with the 24-hour DWI lesion in patients without reperfusion and with the acute PWI and CTP-Tmax thresholds. RESULTS: An ASL-CBF threshold of 40% showed the highest area under the curve (AUC) for detection of the acute penumbra, defined by 24-hour DWI in nonreperfused patients (AUC 0.76, 95% confidence interval, 0.63-0.85), and was also accurate compared with the acute PWI-Tmax+6 seconds penumbral threshold (AUC 0.79, 95% confidence interval, 73-84) and acute CTP-Tmax 5.5 seconds penumbral threshold (AUC 0.77, 95% confidence interval, 72-84). Using a perfusion-to-diffusion mismatch ratio of 1.8:1, an ASL-CBF 40% mismatch compared with PWI-Tmax+ 6 seconds-DWI and CTP mismatch showed good sensitivity (0.81) and specificity (0.71). CONCLUSIONS: ASL-DWI mismatch shows potential to identify salvageable tissue in hyperacute stroke.

How accurate is web-based self-reported height, weight, and body mass index in young adults?

BACKGROUND: Web-based approaches are an effective and convenient medium to deliver eHealth interventions. However, few studies have attempted to evaluate the accuracy of online self-reported weight, and only one has assessed the accuracy of online self-reported height and body mass index (BMI). OBJECTIVE: This study aimed to validate online self-reported height, weight, and calculated BMI against objectively measured data in young Australian adults. METHODS: Participants aged 18-35 years were recruited via advertisements on social media sites and reported their current height and weight as part of an online survey. They then subsequently had the same measures objectively assessed by a trained researcher. RESULTS: Self-reported height was significantly overestimated by a mean of 1.36 cm (SD 1.93; P<.001), while self-reported weight was significantly underestimated by -0.55 kg (SD 2.03; P<.001). Calculated BMI was also underestimated by -0.56 kg/m(2) (SD 0.08; P<.001). The discrepancy in reporting resulted in the misclassification of the BMI category of three participants. Measured and self-reported data were strongly positively correlated (height: r=.98, weight: r=.99, BMI: r=.99; P<.001). When accuracy was evaluated by BMI category and gender, weight remained significantly underreported by females (P=.002) and overweight/obese participants (P=.02). CONCLUSIONS: There was moderate to high agreement between self-reported and measured anthropometric data. Findings suggest that online self-reported height and weight can be a valid method of collecting anthropometric data.

Glutamate and glutamine: a review of in vivo MRS in the human brain.

Our understanding of the roles that the amino acids glutamate (Glu) and glutamine (Gln) play in the mammalian central nervous system has increased rapidly in recent times. Many conditions are known to exhibit a disturbance in Glu-Gln equilibrium, and the exact relationships between these changed conditions and these amino acids are not fully understood. This has led to increased interest in Glu/Gln quantitation in the human brain in an array of conditions (e.g. mental illness, tumor, neuro-degeneration) as well as in normal brain function. Accordingly, this review has been undertaken to describe the increasing number of in vivo techniques available to study Glu and Gln separately, or pooled as 'Glx'. The present MRS methods used to assess Glu and Gln vary in approach, complexity, and outcome, thus the focus of this review is on a description of MRS acquisition approaches, and an indication of relative utility of each technique rather than brain pathologies associated with Glu and/or Gln perturbation. Consequently, this review focuses particularly on (1) one-dimensional (1)H MRS, (2) two-dimensional (1)H MRS, and (3) one-dimensional (13)C MRS techniques.

Prevalence and Impact of Cerebral Microbleeds on Clinical and Safety Outcomes in Acute Ischaemic Stroke Patients Receiving Reperfusion Therapy: A Systematic Review and Meta-Analysis.

BACKGROUND: Cerebral microbleeds (CMBs), a notable neuroimaging finding often associated with cerebral microangiopathy, demonstrate a heightened prevalence in patients diagnosed with acute ischemic stroke (AIS), which is in turn linked to less favourable clinical prognoses. Nevertheless, the exact prevalence of CMBs and their influence on post-reperfusion therapy outcomes remain inadequately elucidated. MATERIALS AND METHODS: Through systematic searches of PubMed, Embase and Cochrane databases, studies were identified adhering to specific inclusion criteria: (a) AIS patients, (b) age ≥ 18 years, (c) CMBs at baseline, (d) availability of comparative data between CMB-positive and CMB-negative groups, along with relevant post-reperfusion therapy outcomes. The data extracted were analysed using forest plots of odds ratios, and random-effects modelling was applied to investigate the association between CMBs and symptomatic intracerebral haemorrhage (sICH), haemorrhagic transformation (HT), 90-day functional outcomes, and 90-day mortality post-reperfusion therapy. RESULTS: In a total cohort of 9776 AIS patients who underwent reperfusion therapy, 1709 had CMBs, with a pooled prevalence of 19% (ES 0.19; 95% CI: 0.16, 0.23, p < 0.001). CMBs significantly increased the odds of sICH (OR 2.57; 95% CI: 1.72; 3.83; p < 0.0001), HT (OR 1.53; 95% CI: 1.25; 1.88; p < 0.0001), as well as poor functional outcomes at 90 days (OR 1.59; 95% CI: 1.34; 1.89; p < 0.0001) and 90-day mortality (OR 1.65; 95% CI: 1.27; 2.16; p < 0.0001), relative to those without CMBs, in AIS patients undergoing reperfusion therapy (encompassing intravenous thrombolysis [IVT], endovascular thrombectomy [EVT], either IVT or EVT, and bridging therapy). Variations in the level of association can be observed among different subgroups of reperfusion therapy. CONCLUSIONS: This meta-analysis underscores a significant association between CMBs and adverse postprocedural safety outcomes encompassing sICH, HT, poor functional outcome, and increased mortality in AIS patients undergoing reperfusion therapy. The notable prevalence of CMBs in both the overall AIS population and those undergoing reperfusion therapy emphasizes their importance in post-stroke prognostication.

Examining for Cavum Septum Pellucidum and Ventricular Enlargement in Retired Elite-Level Rugby League Players.

Objective: A cavum septum pellucidum (CSP) has been reported as a visible brain anomaly in normal individuals as well in some former combat and collision sport athletes. The appearance of CSP with fenestrations and ventricular enlargement are considered associated features of the neuropathological diagnosis of chronic traumatic encephalopathy. The current study examined CSP anatomic features and lateral ventricle size in retired elite rugby league players and controls. Methods: Forty-one retired rugby league players and 41 healthy community controls, similar in age and education, underwent structural MRI scans. CSP grade, CSP length, corpus callosum septal length, and Evans' ratio (for lateral ventricle size) were rated by two of the current study authors. All participants also self-reported concussion exposure histories, depressive symptoms, daytime sleepiness, and impulsivity. They completed a neuropsychological test battery assessing premorbid intellectual functioning, attention, processing speed, language, visuospatial skills, memory, and aspects of executive functioning. Results: The two raters had high agreement for CSP grade (Cohen's κ = 0.80), CSP length [intraclass correlation (ICC) = 0.99], corpus callosum septal length (ICC = 0.73), the CSP/septal ratio (ICC = 0.99), and the Evans' ratio (ICC = 0.75). Twenty-five retired players (61.0%) had an abnormal CSP compared to 17 controls [41.5%; χ ( 1 ,   82 ) 2 = 3.12, p = 0.08, odds ratio = 2.21]. The CSP/septal ratio was larger for retired players than for the controls. The Evans' ratio did not differ between the two groups. In the retired rugby league players (n = 41), those with normal (n = 16) and abnormal (n = 25) CSP grades did not differ across age, age of first exposure to collision sport, years of sport exposure, concussion history, or 23 clinical and cognitive variables. Conclusion: This study revealed a difference in the size of the CSP between retired professional rugby league players and controls. There was no significant difference in the size of the ventricles between the two groups. There were no significant differences between those with vs. without an abnormal CSP on age of first exposure to rugby league, years of exposure to repetitive neurotrauma, number of lifetime concussions, depression, impulsivity, perceived cognitive decline, or on any neuropsychological test.

Differences in Structural Brain Characteristics Between Individuals with Chronic Nonspecific Neck Pain and Asymptomatic Controls: A Case-Control Study.

BACKGROUND: Neck pain is a prevalent and costly problem, but its underlying mechanisms are poorly understood. Neuroimaging studies show alterations in brain morphometry in chronic musculoskeletal pain, but reports on neck pain are scarce. OBJECTIVE: This study investigates (1) differences in brain morphometry between individuals with chronic nonspecific neck pain and asymptomatic individuals and (2) associations between brain morphometry and patient-reported outcomes. METHODS: Sixty-three participants (33 pain, 11 female, mean [SD] age 35 [10] years; 30 control, 12 female, age 35 [11] years) underwent magnetic resonance imaging. Brain regions of interest (ROIs) were determined a priori, outcomes included cortical thickness and volume. Between-group differences were determined using cluster-wise correction for multiple comparisons and analyses of pain-related ROIs. RESULTS: Between-group differences in volume were identified in the precentral, frontal, occipital, parietal, temporal, and paracentral cortices. ROI analyses showed that parahippocampal cortical thickness was larger in the neck pain group (p=0.015, 95% CI: -0.27 to -0.03). Moderate to strong associations between volume and thickness of the cingulate cortex, prefrontal cortex, and temporal lobe and neck pain duration, pain intensity, and neck disability were identified (p-values 0.006 to 0.048). CONCLUSION: Alterations in brain morphology that are associated with clinical characteristics inform the mechanisms underlying chronic nonspecific neck pain and may guide the development of more effective treatment approaches.