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Abstract Objective With potential therapies for many forms of Charcot‐Marie‐Tooth disease (CMT), responsive outcome measures are urgently needed for clinical trials. Quantitative lower limb MRI demonstrated progressive calf intramuscular fat accumulation in the commonest form, CMT1A with large responsiveness. In this study, we evaluated the responsiveness and validity in the three other common forms, due to variants in GJB1 (CMTX1), MPZ (CMT1B) and MFN2 (CMT2A). Methods 22 CMTX1, 21 CMT1B and 21 CMT2A patients and matched controls were assessed at a 1‐year interval. Intramuscular fat fraction (FF) was evaluated using three‐point Dixon MRI at thigh and calf level along with clinical measures including CMT examination score, clinical strength assessment, CMT‐HI and plasma neurofilament light chain. Results All patient groups had elevated muscle fat fraction at thigh and calf levels, with highest thigh FF and atrophy in CMT2A. There was moderate correlation between calf muscle FF and clinical measures (CMTESv2 rho = 0.405; p = 0.001, ankle MRC strength rho = −0.481; p

AbstractBeyond the established effects of subthalamic nucleus deep brain stimulation (STN-DBS) in reducing motor symptoms in Parkinson’s disease, recent evidence has highlighted the effect on non-motor symptoms. However, the impact of STN-DBS on disseminated networks remains unclear. This study aimed to perform a quantitative evaluation of network-specific modulation induced by STN-DBS using Leading Eigenvector Dynamics Analysis (LEiDA). We calculated the occupancy of resting-state networks (RSNs) in functional MRI data from 10 patients with Parkinson’s disease implanted with STN-DBS and statistically compared between ON and OFF conditions. STN-DBS was found to specifically modulate the occupancy of networks overlapping with limbic RSNs. STN-DBS significantly increased the occupancy of an orbitofrontal limbic subsystem with respect to both DBS OFF (p = 0.0057) and 49 age-matched healthy controls (p = 0.0033). Occupancy of a diffuse limbic RSN was increased with STN-DBS OFF when compared with healthy controls (p = 0.021), but not when STN-DBS was ON, which indicates rebalancing of this network. These results highlight the modulatory effect of STN-DBS on components of the limbic system, particularly within the orbitofrontal cortex, a structure associated with reward processing. These results reinforce the value of quantitative biomarkers of RSN activity in evaluating the disseminated impact of brain stimulation techniques and the personalization of therapeutic strategies.

Ao abordar as maneiras pela quais as tradições religiosas africanas transitaram pelo Atlântico durante o tráfico de cativos, este artigo enfatiza uma abordagem teológica da religião africana. As tradições religiosas africanas geralmente têm figuras espirituais de caráter local: ancestrais, divindades territorialmente delimitadas e entidades espirituais menores. As principais exceções se encontram em áreas como Angola, onde divindades cristãs foram descobertas na África; e as áreas de língua Gbe (no Togo, Benin e Nigéria), onde algumas divindades não foram definidas territorialmente. Embora geralmente divindades africanas não pudessem atravessar o oceano, as técnicas de localização de entidades espirituais por revelação contínua o fizeram, e assim novas divindades foram localizadas no Brasil. Para muitos africanos no Brasil, os santos católicos conhecidos em Angola tornaram-se foco de adoração e propiciação no Brasil; e há evidências documentais de que a revelação contínua no Brasil permitiu que as divindades da área de língua gbe também transitassem pelo oceano, resultando nos estágios iniciais do desenvolvimento do candomblé.

Background and purposePost-thrombectomy intracranial hemorrhages (PTIH) are dangerous complications of acute ischemic stroke (AIS) following mechanical thrombectomy. We aimed to investigate if S100b levels in AIS clots removed by mechanical thrombectomy correlated to increased risk of PTIH.MethodsWe analyzed 122 thrombi from 80 AIS patients in the RESTORE Registry of AIS clots, selecting an equal number of patients having been pre-treated or not with rtPA (40 each group). Within each subgroup, 20 patients had developed PTIH and 20 patients showed no signs of hemorrhage. Gross photos of each clot were taken and extracted clot area (ECA) was measured using ImageJ. Immunohistochemistry for S100b was performed and Orbit Image Analysis was used for quantification. Immunofluorescence was performed to investigate co-localization between S100b and T-lymphocytes, neutrophils and macrophages. Chi-square or Kruskal-Wallis test were used for statistical analysis.ResultsPTIH was associated with higher S100b levels in clots (0.33 [0.08–0.85] vs. 0.07 [0.02–0.27] mm2, H1 = 6.021, P = 0.014*), but S100b levels were not significantly affected by acute thrombolytic treatment (P = 0.386). PTIH was also associated with patients having higher NIHSS at admission (20.0 [17.0–23.0] vs. 14.0 [10.5–19.0], H1 = 8.006, P = 0.005) and higher number of passes during thrombectomy (2 [1–4] vs. 1 [1–2.5], H1 = 5.995, P = 0.014*). S100b co-localized with neutrophils, macrophages and with T-lymphocytes in the clots.ConclusionsHigher S100b expression in AIS clots, higher NIHSS at admission and higher number of passes during thrombectomy are all associated with PTIH. Further investigation of S100b expression in AIS clots by neutrophils, macrophages and T-lymphocytes could provide insight into the role of S100b in thromboinflammation.

Cortical remapping after hand loss in the primary somatosensory cortex (S1) is thought to be predominantly dictated by cortical proximity, with adjacent body parts remapping into the deprived area. Traditionally, this remapping has been characterised by changes in the lip representation, which is assumed to be the immediate neighbour of the hand based on electrophysiological research in non-human primates. However, the orientation of facial somatotopy in humans is debated, with contrasting work reporting both an inverted and upright topography. We aimed to fill this gap in the S1 homunculus by investigating the topographic organisation of the face. Using both univariate and multivariate approaches we examined the extent of face-to-hand remapping in individuals with a congenital and acquired missing hand (hereafter one-handers and amputees, respectively), relative to two-handed controls. Participants were asked to move different facial parts (forehead, nose, lips, tongue) during functional MRI (fMRI) scanning. We first confirmed an upright face organisation in all three groups, with the upper-face and not the lips bordering the hand area. We further found little evidence for remapping of both forehead and lips in amputees, with no significant relationship to the chronicity of their phantom limb pain (PLP). In contrast, we found converging evidence for a complex pattern of face remapping in congenital one-handers across multiple facial parts, where relative to controls, the location of the cortical neighbour – the forehead – is shown to shift away from the deprived hand area, which is subsequently more activated by the lips and the tongue. Together, our findings demonstrate that the face representation in humans is highly plastic, but that this plasticity is restricted by the developmental stage of input deprivation, rather than cortical proximity.

Background Emerging evidence suggests that clinical and economic benefits of treatment with mechanical thrombectomy vary by level of reperfusion achieved, and the number of passes required to achieve revascularization. This study aimed to investigate the INFluence of revascularization Attempts on Clinical outcomes of mechanical Thrombectomy and the economic BURDEN (INFACT BURDEN) in Ireland using single center real‐world data from the Irish National Thrombectomy Service database. Methods Primary clinical outcomes were reperfusion (modified thrombolysis in cerebral infarction 2b‐3 or 2) among patients treated with 1–3 passes compared with ≥4 passes. Multivariable generalized linear models examined the association between number of passes with outcomes, with adjustment for covariates that may affect outcomes (eg, age, pre‐procedure modified Rankin Scale, National Institutes of Health Stroke Scale, Alberta Stroke Program Early CT Score, occlusion site, time from symptom onset to groin puncture). A 90‐day decision‐tree and Markov model with a 5‐year time horizon evaluated the cost‐effectiveness of mechanical thrombectomy from the Irish public healthcare payer perspective. Results Eight hundred twenty three patients met the inclusion criteria. Compared with patients in the ≥4 passes group, patients in the 1–3 passes group achieved a significantly higher rate of successful reperfusion (94% versus 78%, odds ratio [OR], 4.7; P

Background Various mechanical thrombectomy devices including stent retrievers (STRs), contact aspiration (CA) catheters, and balloon guide catheters (BGCs) are used in both isolation and combination for the treatment of acute ischemic stroke. A new generation of Super‐Bore 088″ aspiration catheters are being trialed clinically. We evaluated the in vitro revascularization performance of current and novel thrombectomy approaches in treating soft (red blood cell–rich) and stiff (fibrin/platelet‐rich) clots at internal carotid artery (ICA) and middle cerebral artery (MCA) occlusion sites. Methods National University of Ireland Galway Research Ethics Committee approved the study. Two human blood clot phenotypes were used to form ICA‐terminus (20‐mm) and MCA–M1 segment (10‐mm) occlusions in an in vitro thrombectomy model. Thrombectomy setups tested were CA: Millipede 088, SOFIA Plus+conventional guide catheter, SOFIA Plus+BGC and Combination; Millipede 088+STR, SOFIA Plus+BGC+STR, SOFIA Plus+conventional guide catheter+STR. Ten replicates of each experiment were performed totaling 120 tests. Revascularization endpoints were first‐pass effect, final modified Thrombolysis in Cerebral Infarction (mTICI) 2c/3, and procedural‐related distal emboli. Results Millipede 088 CA achieved the highest first‐pass effect rate in ICA‐terminus (60%) and MCA–M1 segment (100%) occlusions and lowest number of procedural‐related distal emboli compared with all other device setups, followed by the combined Millipede 088+STR technique. Amongst the conventional techniques, higher first‐pass effect rates were observed with the combined technique using a BGC (40%) than 6F CA (20%) in ICA‐terminus occlusions whereas the reverse was seen in MCA–M1 segment occlusions, with 6F CA performing better than combined approaches (60% versus 50%). BGCs may provide a revascularization benefit in ICA‐terminus occlusions. Rates of first‐pass effect and final mTICI 2c/3 were better for stiff clots compared with soft clots for all treatment approaches at both occlusion sites. Conclusion Millipede 088 CA was the most effective technique for all clot types and occlusion locations. Across conventional techniques, CA seems to be more effective in MCA–M1 segment occlusions, while the combined technique performed better in ICA occlusions. Clot composition influences the success of each technique.

With therapeutic trials on the horizon for Charcot-Marie-Tooth type 1A (CMT1A), reliable, valid, and responsive clinical outcome assessments and biomarkers are essential. Accelerate Clinical Trials in CMT (ACT-CMT) is an international study designed to address important gaps in CMT1A clinical trial readiness including the lack of a validated, responsive functional outcome measure for adults, and a lack of validated biomarkers for multicenter application in clinical trials in CMT1A. The primary aims of ACT-CMT include validation of the Charcot-Marie-Tooth Functional Outcome Measure, magnetic resonance imaging of intramuscular fat accumulation as a lower limb motor biomarker, and in-vivo reflectance confocal microscopy of Meissner corpuscle sensory receptor density, a sensory biomarker. Initial studies have indicated that these measures are feasible, reliable and valid. A large prospective, multi-site study is necessary to fully validate and examine the responsiveness of these outcome measures in relation to existing outcomes for use in future clinical trials involving individuals with CMT1A. Two hundred 15 adults with CMT1A are being recruited to participate in this prospective, international, multi-center study. Serial assessments, up to 3 years, are performed and include the CMT-FOM, CMT Exam Score-Rasch, Overall Neuropathy Limitations Scale, CMT-Health Index, as well as nerve conduction studies, and magnetic resonance imaging and Meissner corpuscle biomarkers. Correlations using baseline data will be examined for validity. Longitudinal analyses will document the changes in function, intramuscular fat accumulation, Meissner corpuscle sensory receptor density. Lastly, we will use anchor-based and other statistical methods to determine the minimally clinically important change for these clinical outcome assessments and biomarkers in CMT1A. Reliable, and responsive clinical outcome assessments of function and disease progression biomarkers are urgently needed for application in early and late phase clinical trials in CMT1A. The ACT-CMT study protocol will address this need through the prospective, longitudinal, multicenter examination in unprecedented detail of novel and existing clinical outcome assessments and motor and sensory biomarkers, and enhance international clinical trial infrastructure, training and preparedness for future therapeutic trials in CMT and related neuropathies.

Background and AimsBesides the crucial role in the treatment of acute ischemic stroke (AIS), mechanical thrombectomy represents a unique opportunity for researchers to study the retrieved clots, with the possibility of unveiling biological patterns linked to stroke pathophysiology and etiology. We aimed to develop a shotgun proteomic approach to study and compare the proteome of formalin-fixed paraffin-embedded (FFPE) cardioembolic and large artery atherosclerotic (LAA) clots.MethodsWe used 16 cardioembolic and 15 LAA FFPE thrombi from 31 AIS patients. The thrombus proteome was analyzed by label-free quantitative liquid chromatography-tandem mass spectrometry (LC-MS/MS). MaxQuant v1.5.2.8 and Perseus v.1.6.15.0 were used for bioinformatics analysis. Protein classes were identified using the PANTHER database and the STRING database was used to predict protein interactions.ResultsWe identified 1,581 protein groups as part of the AIS thrombus proteome. Fourteen significantly differentially abundant proteins across the two etiologies were identified. Four proteins involved in the ubiquitin-proteasome pathway, blood coagulation or plasminogen activating cascade were identified as significantly abundant in LAA clots. Ten proteins involved in the ubiquitin proteasome-pathway, cytoskeletal remodeling of platelets, platelet adhesion or blood coagulation were identified as significantly abundant in cardioembolic clots.ConclusionOur results outlined a set of 14 proteins for a proof-of-principle characterization of cardioembolic and LAA FFPE clots, advancing the proteome profile of AIS human thrombi and understanding the pathophysiology of ischemic stroke.

Background: Dementia with Lewy bodies (DLB) is the second most common form of dementia. Current symptomatic treatment with medications remains inadequate. Deep brain stimulation of the nucleus basalis of Meynert (NBM DBS) has been proposed as a potential new treatment option in dementias. Objective: To assess the safety and tolerability of low frequency (20 Hz) NBM DBS in DLB patients and explore its potential effects on both clinical symptoms and functional connectivity in underlying cognitive networks. Methods: We conducted an exploratory randomised, double-blind, crossover trial of NBM DBS in six DLB patients recruited from two UK neuroscience centres. Patients were aged between 50 and 80 years, had mild-moderate dementia symptoms and were living with a carer-informant. Patients underwent image guided stereotactic implantation of bilateral DBS electrodes with the deepest contacts positioned in the Ch4i subsector of NBM. Patients were subsequently assigned to receive either active or sham stimulation for six weeks, followed by a two week washout period, then the opposite condition for six weeks. Safety and tolerability of both the surgery and stimulation were systematically evaluated throughout. Exploratory outcomes included the difference in scores on standardised measurements of cognitive, psychiatric and motor symptoms between the active and sham stimulation conditions, as well as differences in functional connectivity in discrete cognitive networks on resting state fMRI. Results: Surgery and stimulation were well tolerated by all six patients (five male, mean age 71.33 years). One serious adverse event occurred: one patient developed antibiotic-associated colitis, prolonging his hospital stay by two weeks. No consistent improvements were observed in exploratory clinical outcome measures, but the severity of neuropsychiatric symptoms reduced with NBM DBS in 3/5 patients. Active stimulation was associated with functional connectivity changes in both the default mode network and the frontoparietal network. Conclusion: Low frequency NBM DBS can be safely conducted in DLB patients. This should encourage further exploration of the possible effects of stimulation on neuropsychiatric symptoms and corresponding changes in functional connectivity in cognitive networks. Trial registration number: NCT02263937.

Introduction: Previous studies demonstrated that both the location of the distal access catheter tip and angle of aspiration have a significant impact on revascularization outcomes1,2. A direct aspiration First‐Pass technique (ADAPT) with large‐bore aspiration catheters has emerged as a fast, safe, and effective thrombectomy technique. Maximizing the catheter‐to‐vessel size has previously been shown to enhance distal flow control resulting in improved in‐vitro revascularization rates for aspiration thrombectomy3. However, physicians differ in their preference for aspiration catheter tip placement, typically either positioning the catheter tip at the ‘face’ of the clot or advancing the catheter tip into the clot to engage it. We hypothesize that sizing the aspiration catheter outer diameter (OD) to the inner diameter (ID) of the vessel and embedding the catheter tip in the clot may result in ‘pinning’ fragments of clot between the catheter and vessel wall, thereby negatively affecting revascularization outcomes. Withdrawal of the aspiration catheter under continuous aspiration may mitigate this effect. We investigate the influence of catheter tip position and aspiration technique on ADAPT revascularization success with various sizes of aspiration catheters. Methods: Two clot analogues phenotypes (RBC‐Rich and Fibrin/Platelet‐Rich) were created from human blood and used to form occlusions in an In‐vitro thrombectomy model as previously described4. Two catheter tip positions and three techniques were investigated; 1). Catheter tip proximal to the face of the clot followed by conventional aspiration, 2). Catheter tip ‘embedded’ into the clot followed by conventional aspiration, and 3). Catheter tip ‘embedded’ into the clot followed by conventional aspiration and aspiration on catheter withdrawal even if clot ingestion occurred. Two aspiration catheters were investigated; Millipede 088’’ (Perfuze Ltd) and SOFIA Plus (Terumo). Multiple replicates of each test were performed. Endpoints were First‐Pass Effect and procedural‐related distal emboli from 200–1000µm. Results: Maximizing the catheter‐to‐vessel size increases success of the ADAPT approach when the tip is located proximal to the clot face (Fig 1 A&B); Millipede 088 achieves a higher First‐Pass Effect rate than SOFIA Plus. Sizing the catheter‐to‐vessel and embedding the catheter tip into the clot (Figure 1C) results in ‘pinning’ of clot fragments between the catheter and vessel wall (Figure 1D) resulting in lower rates of First‐Pass Effect. Withdrawing the catheter under continuous aspiration increases the success of the embedding method by capturing ‘pinned’ fragments. Conclusions: The position of the aspiration catheter tip and aspiration technique used both influence the success of ADAPT procedures. Sizing the catheter‐to‐vessel results in improved revascularization. However, embedding the tip into the clot when the vessel is similar in ID to the catheter OD may reduce First‐Pass Effect rates. To optimize the rates of First‐Pass Effect, aspiration catheters may be positioned at the proximal face of the clot or retracted under continuous aspiration if wedged into the clot.

Introduction Recent advances in stroke management and care have resulted in improved survival and outcomes. However, providing equitable access to acute care, rehabilitation and longer-term stroke care is challenging. Recent Irish evidence indicates variation in stroke outcomes across hospitals, and a need for continuous audit of stroke care to support quality improvement. The aim of this project is to develop a core minimum dataset for use in the new Irish National Audit of Stroke (INAS), which aims to improve the standard of stroke care in Ireland. This paper outlines the protocol for conducting a scoping review of international practice and guidelines in auditing acute and non-acute stroke care. Objective Identify data items that are currently collected by stroke audits internationally, and identify audit guidelines that exist for recommending inclusion of content in stroke audit datasets. Methods and analysis This scoping review will be conducted in accordance with the Preferred Reporting Items for Systematic Reviews extension for Scoping Reviews (PRISMA-ScR). We will search the following databases: Medline Ovid; Embase; CINAHL EBSCOHost. Grey literature will also be searched for relevant materials, as will relevant websites. Study selection and review will be carried out independently by two researchers, with discrepancies resolved by a third. Data charting and synthesis will involve sub-dividing relevant sources of evidence, and synthesising data into three categories: i) acute stroke care; ii) non-acute stroke care; and iii) audit data collection procedures and resourcing. Data will be charted using a standardised form specific to each category. Consultation with knowledge users will be conducted at all stages of the scoping review. Discussion This scoping review will contribute to a larger project aimed at developing an internationally benchmarked stroke audit tool that will be used prospectively to collect data on all stroke admissions in Ireland, encompassing both acute and non-acute data items.

Objectives: To investigate the relative somatotopic organization of the motor corticospinal/corticobulbar foot, hand, lip and tongue fascicles by combining fMRI with DTI and to examine the influence of subjacent intrinsic tumours on these fascicles. Methods: The study was approved by the local ethics committee. Seven male and three female volunteers (median age: 35 years) and one female and eight male patients with brain tumours (median age: 37 years) were scanned on a 1.5-T MRI scanner. fMRI data, analysed using SPM5, identified the motor task-driven fMRI grey matter activations of the hand, foot, lips and tongue as seed regions for probabilistic tractography. The relationship between the components of the CST was assessed and the distances between them were measured. A statistical comparison was performed comparing these distances in the group of healthy hemispheres with those of the group of non-affected hemispheres and healthy hemispheres. Results: Hand fascicles were identified in all subjects (38/38, 100%), followed by foot (32/38, 84%), lip (31/38, 81%) and tongue fascicles (28/38, 74%). At superior levels, the hand fascicles were anterolateral to the foot fascicles in 77–93% of healthy hemispheres (HH), in 50–71% of non-affected patients' hemispheres (pH) and in 67–89% of affected PH. At inferior levels, the hand fascicles were either anteromedial in 46–45% of HH or anterior in 75% of non-affected PH and in 67–83% of affected PH. Tongue and lip fascicles overlapped in 25–45% of HH, in 10–20% of non-affected PH and in 15–25% of affected PH. No significant difference was found between the group of affected hemispheres and that of healthy and non-affected hemispheres. Conclusion: The somatotopy of the hand fascicles in relation to the foot fascicles was anterolateral in patients and volunteers at superior levels but anteromedial in volunteers and mostly anterior in patients at inferior levels. The lip and tongue fascicles generally overlapped. Intracranial tumours displaced the motor fascicles without affecting their relative somatotopy. Keywords: Functional MRI (fMRI), Diffusion tensor imaging (DTI), Corticospinal tract (CST), Corticobulbar tract (CBT), Brain tumours

Prion diseases are a group of rare neurodegenerative conditions characterised by a high rate of progression and highly heterogeneous phenotypes. Whilst the most common form of prion disease occurs sporadically (sporadic Creutzfeldt–Jakob disease, sCJD), other forms are caused by prion protein gene mutations, or exposure to prions in the diet or by medical procedures, such us surgeries. To date, there are no accurate quantitative imaging biomarkers that can be used to predict the future clinical diagnosis of a healthy subject, or to quantify the progression of symptoms over time. Besides, CJD is commonly mistaken for other forms of dementia. Due to the heterogeneity of phenotypes and the lack of a consistent geometrical pattern of disease progression, the approaches used to study other types of neurodegenerative diseases are not satisfactory to capture the progression of human form of prion disease. In this paper, using a tailored framework, we aim to classify and stratify patients with prion disease, according to the severity of their illness. The framework is initialised with the extraction of subject-specific imaging biomarkers. The extracted biomakers are then combined with genetic and demographic information within a Gaussian Process classifier, used to calculate the probability of a subject to be diagnosed with prion disease in the next year. We evaluate the effectiveness of the proposed method in a cohort of patients with inherited and sporadic forms of prion disease. The model has shown to be effective in the prediction of both inherited CJD (92% of accuracy) and sporadic CJD (95% of accuracy). However the model has shown to be less effective when used to stratify the different stages of the disease, in which the average accuracy is 85%, whilst the recall is 59%. Finally, our framework was extended as a differential diagnosis tool to identify both forms of CJD among another neurodegenerative disease. In summary we have developed a novel method for prion disease diagnosis and prediction of clinical onset using multiple sources of features, which may have use in other disorders with heterogeneous imaging features. Keywords: Prion diseases, Inherited Creutzfeldt–Jakob disease, Sporadic Creutzfeldt–Jakob disease, Diagnosis, Biomarkers, Subjects’ stratification, Gaussian process

An internal septum within a basilar artery aneurysm is an infrequent anomaly and is very rarely reported in the literature. We report a 62-year-old lady that was incidentally diagnosed with basilar tip aneurysm. Further imaging with magnetic resonance imaging (MRI) revealed internal septation within this aneurysm which was later confirmed with digital subtraction angiography (DSA). She underwent coil embolisation, which involved technical manipulation of the microcatheter and the balloon to enable coiling of each separate aneurysm compartment. We present this case to illustrate the effect of this anatomical variation on the selection of endovascular treatment strategy.

Deep brain stimulation (DBS) is an established treatment for patients with movement disorders. Patients receiving chronic DBS provide a unique opportunity to explore the underlying mechanisms of DBS using functional MRI. It has been shown that the main safety concern with MRI in these patients is heating at the electrode tips - which can be minimised with strict adherence to a supervised acquisition protocol using a head-transmit/receive coil at 1.5T. MRI using the body-transmit coil with a multi-channel receive head coil has a number of potential advantages including an improved signal-to-noise ratio.We compared the safety of cranial MRI in an in vitro model of bilateral DBS using both head-transmit and body-transmit coils. We performed fibre-optic thermometry at a Medtronic ActivaPC device and Medtronic 3389 electrodes during turbo-spin echo (TSE) MRI using both coil arrangements at 1.5T and 3T, in addition to gradient-echo echo-planar fMRI exposure at 1.5T. Finally, we investigated the effect of transmit-coil choice on DBS stimulus delivery during MRI.Temperature increases were consistently largest at the electrode tips. Changing from head- to body-transmit coil significantly increased the electrode temperature elevation during TSE scans with scanner-reported head SAR 0.2W/kg from 0.45°C to 0.79°C (p

PURPOSE: This systematic review evaluated the clinical utility of single photon emission computed tomography (SPECT) in traumatic brain injury (TBI). METHODS: After defining a PICO Statement (Population, Intervention, Comparison and Outcome Statement), PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) criteria were applied to identify 1600 articles. After screening, 374 articles were eligible for review. Inclusion for review was focus on SPECT in the setting of mild, moderate, or severe TBI with cerebral lobar specificity of SPECT findings. Other inclusion criteria were comparison modalities in the same subjects and articles in English. Foreign language articles, SPECT studies that did not include comparison modalities, and case reports were not included for review. RESULTS: We identified 19 longitudinal and 52 cross-sectional studies meeting inclusion criteria. Three longitudinal studies examined diagnostic predictive value. The first showed positive predictive value increases from initial SPECT scan shortly after trauma to one year follow up scans, from 59% to 95%. Subsequent work replicated these results in a larger cohort. Longitudinal and cross sectional studies demonstrated SPECT lesion localization not detected by CT or MRI. The most commonly abnormal regions revealed by SPECT in cross-sectional studies were frontal (94%) and temporal (77%) lobes. SPECT was found to outperform both CT and MRI in both acute and chronic imaging of TBI, particularly mild TBI. It was also found to have a near 100% negative predictive value. CONCLUSIONS: This review demonstrates Level IIA evidence (at least one non-randomized controlled trial) for the value of SPECT in TBI. Given its advantages over CT and MRI in the detection of mild TBI in numerous studies of adequate quality, and given its excellent negative predictive value, it may be an important second test in settings where CT or MRI are negative after a closed head injury with post-injury neurological or psychiatric symptoms.

This paper examines the theory of mixed constitution and the sociological doctrine of anacyclosis in Book VI of Polybius’ Histories. The ideal of a mixed government was popularized by Polybius, who saw the Roman Republic as a manifestation of Aristotle’s theory. Monarchy was embodied by the consuls, the aristocracy by the Senate, and democracy by the elections and great public gatherings of the assemblies. Each institution complements and also checks the others, presumably guaranteeing stability and prosperity. Polybius makes further distinction in the forms of government by including the nefarious counterparts to the ones mentioned above; tyranny, oligarchy, and ochlocrazy. These governments, according to Polybius cycle in a process called anacyclosis, which begins with monarchy and ends with ochlocrazy. The Roman model avoids this problem when it sets up the republic and becomes a mixture of the three types. Of course, none of this can happen without the censure of the people and no man can be installed in any position without the vote of the people. It is in this way, as Polybius understands it, that the strength of the Roman State is shown and held together. Polybius’ political beliefs have had a continuous appeal to republican thinkers from Cicero to Montesquieu to the Founding Fathers of the United States

The Swiss-based “StratXX†project during 2006-2007 has been developing a stratospheric lighter-than-air platform for deployment of telecommunications and environmental monitoring services. In support of a first round of experimental trials, a WiMAX communications subsystem, including platform payload and ground stations, has been developed. The communications system design and results of terrestrial pretrials are reported.

Background During the COVID-19 pandemic, decreased volumes of stroke admissions and mechanical thrombectomy were reported. The study’s objective was to examine whether subarachnoid haemorrhage (SAH) hospitalisations and ruptured aneurysm coiling interventions demonstrated similar declines.Methods We conducted a cross-sectional, retrospective, observational study across 6 continents, 37 countries and 140 comprehensive stroke centres. Patients with the diagnosis of SAH, aneurysmal SAH, ruptured aneurysm coiling interventions and COVID-19 were identified by prospective aneurysm databases or by International Classification of Diseases, 10th Revision, codes. The 3-month cumulative volume, monthly volumes for SAH hospitalisations and ruptured aneurysm coiling procedures were compared for the period before (1 year and immediately before) and during the pandemic, defined as 1 March–31 May 2020. The prior 1-year control period (1 March–31 May 2019) was obtained to account for seasonal variation.Findings There was a significant decline in SAH hospitalisations, with 2044 admissions in the 3 months immediately before and 1585 admissions during the pandemic, representing a relative decline of 22.5% (95% CI −24.3% to −20.7%, p