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QUESTION: In adults with attention deficit hyperactivity disorder (ADHD), is bupropion more effective than placebo?Design6 week randomised (allocation concealed*), blinded {clinicians, patients, and outcome assessors}*, placebo controlled trial.SettingPsychopharmacology clinic of the Massachusetts General Hospital, Boston, Massachusetts, USA.Patients40 patients who were 20-59 years of age (mean age 38 y, 55% men) and had ADHD according to DSM-IV criteria. Exclusion criteria were clinically significant chronic medical conditions, history of cardiac arrhythmias or seizures, intellectual impairment (intelligence quotient < 75), organic brain disorders, clinically unstable psychiatric conditions, bipolar disorder, drug or alcohol abuse within the past 6 months, or current use of psychotropics. 38 patients (95%) completed the study.InterventionPatients were allocated to 200 mg/day of bupropion (n=21) or placebo (n=19). The dose was tirated up to 200 mg twice daily by week 4.Main outcome measuresADHD, depression, and anxiety symptoms were measured using the Clinical Global Impression (CGI) scale, the ADHD Rating Scale, the Hamilton Depression Rating Scale (HDRS), the Beck Depression Inventory (BDI), and the Hamilton Anxiety Rating Scale (HARS). Adverse events were also assessed.Main resultsMore patients who received bupropion showed improvement than those who received placebo (score of 1 or 2 [much or very much improved] on the CGI scale, p = 0.007; and 330% reduction in scores on the DSM-IV ADHD symptom checklist, p=0.02) (table). More ADHD symptoms improved in the bupropion group patients than in placebo group patients (100% a 44% of symptoms, p < 0.001). The groups did not differ for scores on the HDRS, the BDI, or the HARS. The groups did not differ for adverse events (table); no serious adverse drug events occurred.ConclusionIn adults with attention deficit hyperactivity disorder, bupropion was more effective than placebo in improving symptoms and did not produce severe adverse effects.*See glossary.** Information provided by author. [ABSTRACT FROM AUTHOR]

Objective: Many patients recruited in the Treatment of Brain Arteriovenous Malformations Study (TOBAS) are managed conservatively. The aim of this study was to monitor what happened to those patients., Methods: TOBAS comprises two randomized controlled trials and multiple prospective registries. All patients with brain arteriovenous malformations (AVMs) can participate. This report concerns patients selected for conservative management. The primary trial outcome measure is related death or dependency (modified Rankin Scale [mRS] score > 2) at 10 years. Secondary outcomes include intracranial hemorrhages, nonhemorrhagic neurological events, and serious adverse events (SAEs). For this report, outcome results are presented using patient-years, Kaplan-Meier survival curves, and Cox log-rank tests. There was no blinding., Results: From June 2014 to May 2021, 1010 patients were recruited, of whom 498 (49%) were proposed the prospective observation registry. After exclusions, 434 (87%) patients remained for analysis. The majority of patients had unruptured AVMs (378/434 [87%]), of which 195 (52%) were low grade (Spetzler-Martin grade I or II). During a mean follow-up period of 3.2 years (total 1368 patient-years), the primary outcome occurred in 23 of 434 (5%) patients, corresponding to an incidence of 1.7 (95% CI 1.1-2.5) per 100 patient-years. For unruptured AVMs the incidence was 1.1 (95% CI 0.7-1.9) per 100 patient-years, and for low-grade unruptured AVMs it was 0.6 (95% CI 0.2-1.7) per 100 patient-years. Poor outcomes were more frequent in patients with a history of rupture (HR 5.6 [95% CI 2.4-13.0], p < 0.001), infratentorial AVMs (HR 2.9 [95% CI 1.1-7.3], p = 0.027), and age ≥ 55 years (HR 3.2 [95% CI 1.4-7.6], p = 0.007). Major intracranial hemorrhage occurred in 35 of 434 (8%) patients (incidence of 2.6 [95% CI 1.9-3.6] per 100 patient-years; 2.0 [95% CI 1.3-2.9] per 100 patient-years for unruptured AVMs and 1.3 [95% CI 0.6-2.6] per 100 patient-years for low-grade unruptured AVMs). Major AVM hemorrhages were more frequent in ruptured (HR 4.4 [95% CI 2.1-8.9], p < 0.001), large (HR 2.6 [95% CI 1.1-6.6], p = 0.039), and high-grade (HR 2.5 [95% CI 1.2-5.3], p = 0.013) AVMs and those with deep venous drainage (HR 2.1 [95% CI 1.1-4.2], p = 0.032). SAEs occurred in 48 of 434 (11%) patients (incidence of 3.6 [95% CI 2.7-4.8] per 100 patient-years). For unruptured AVMs the incidence was 2.8 (95% CI 2.0-4.0) per 100 patient-years, and for low-grade unruptured AVMs it was 1.8 (95% CI 1.0-3.2) per 100 patient-years., Conclusions: Nearly half of TOBAS participants were observed. Rates of untoward neurological events were within expected boundaries.

Objective: The Fluid And White matter Suppression (FLAWS) MRI sequence provides multiple T1-weighted contrasts of the brain in a single acquisition. However, the FLAWS acquisition time is approximately 8 min with a standard GRAPPA 3 acceleration factor at 3 T. This study aims at reducing the FLAWS acquisition time by providing a new sequence optimization based on a Cartesian phyllotaxis k-space undersampling and a compressed sensing (CS) reconstruction. This study also aims at showing that T1 mapping can be performed with FLAWS at 3 T., Materials and Methods: The CS FLAWS parameters were determined using a method based on a profit function maximization under constraints. The FLAWS optimization and T1 mapping were assessed with in-silico, in-vitro and in-vivo (10 healthy volunteers) experiments conducted at 3 T., Results: In-silico, in-vitro and in-vivo experiments showed that the proposed CS FLAWS optimization allows the acquisition time of a 1 mm-isotropic full-brain scan to be reduced from [Formula: see text] to [Formula: see text] without decreasing image quality. In addition, these experiments demonstrate that T1 mapping can be performed with FLAWS at 3 T., Discussion: The results obtained in this study suggest that the recent advances in FLAWS imaging allow to perform multiple T1-weighted contrast imaging and T1 mapping in a single [Formula: see text] sequence acquisition., (© 2023. The Author(s), under exclusive licence to European Society for Magnetic Resonance in Medicine and Biology (ESMRMB).)

Introduction: The use of three-dimensional (3D) reconstruction and printing technology, together with extended reality applied to advanced heart failure adult patients with complex anatomy, is rapidly spreading in clinical practice. We report practical experience with application to acute and chronic heart failure: planning and performing mechanical circulatory device insertion or heart transplantation., Methods: From November 2019 until February 2022, 53 3D virtual biomodels were produced for intervention planning (using Virtual/Augmented Reality and/or 3D printing), following a specific segmentation and preprocessing workflow for biomodelling, in patients with advanced heart failure due to structural heart disease or cardiomyopathies. Four of those patients were complex cases requiring mechanical circulatory support implant procedures in our center., Results: One short-term and three long-term ventricular assist device system were successfully clinically implanted after application of this technique. In other two cases with extremely high procedural risk, visualized after application of this multimodality imaging, heart transplantation was elected., Conclusion: 3D printing based planning and virtual procedure simulation, are of great importance to select appropriate candidates for mechanical circulatory support in case of complex patient anatomy and may help to diminish periprocedural complications. Extended reality represents a perspective tool in planification of complex surgical procedures or ventricular assist device insertion in this setting., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Stepanenko, Perez, Ferre, Ybarra Falcón, Pérez de la Sota, San Roman, Redondo Diéguez and Baladron.)

Background: In neurovascular treatment planning, endovascular devices to manage complex intracranial aneurysms requiring intervention are often selected based on conventional measurements and interventional neuroradiologist experience. A recently developed technology allows a patient-specific 3D-printed model to mimic the navigation experience. The goal of this study was to assess the effect of pre-procedure 3D simulation on procedural and clinical outcomes for wide-neck aneurysm embolization., Materials & Methods: In this unblinded, non-randomized, prospective, multicenter study conducted from November 18 through December 20, patients with complex intracranial aneurysms (neck > 4 mm or ratio < 2 1 ) were treated by WEB or flow diverter stents (FDS). The primary endpoint was concordance between simulation and procedure, 3D-printed model accuracy as well as embolization outcomes including complications, procedure times, and radiation dose were also assessed. Secondary endpoint was to compare versus a retrospective WEB cohort., Results: Twenty-one patients were treated, 76% of cases by WEB and 24% by FDS. Concordance between post-simulation and real procedure efficiency was 0.85 [0.69 - 1.00] for size device selection and 0.93 [0.79 - 1.00] for wall-apposition/aneurysm neck closure. Geometrical accuracy of the 3D-printed model showed a mean absolute shift of 0.11 mm. Two complications without major clinical impact were reported with a post-operative mRS similar to pre-procedure mRS for all patients., Conclusions: Rehearsal using accurate 3D-printed patient-specific aneurysm models enabled optimization of embolization strategy, resulting in reduced procedure duration and cumulative fluoroscopy time which translated to reduced radiation exposure compared to procedures performed without simulation., Competing Interests: Declaration of Competing Interest None, (Copyright © 2021 Elsevier Masson SAS. All rights reserved.)

Introduction: Apathy, as defined as a deficit in goal-directed behaviors, is a critical clinical dimension in depression associated with chronic impairment. Little is known about its cerebral perfusion specificities in depression. To explore neurovascular mechanisms underpinning apathy in depression by pseudo-continuous arterial spin labeling (pCASL) magnetic resonance imaging (MRI)., Methods: Perfusion imaging analysis was performed on 90 depressed patients included in a prospective study between November 2014 and February 2017. Imaging data included anatomical 3D T1-weighted and perfusion pCASL sequences. A multiple regression analysis relating the quantified cerebral blood flow (CBF) in different regions of interest defined from the FreeSurfer atlas, to the Apathy Evaluation Scale (AES) total score was conducted., Results: After confound adjustment (demographics, disease and clinical characteristics) and correction for multiple comparisons, we observed a strong negative relationship between the CBF in the left anterior cingulate cortex (ACC) and the AES score (standardized beta = -0.74, corrected p value = 0.0008)., Conclusion: Our results emphasized the left ACC as a key region involved in apathy severity in a population of depressed participants. Perfusion correlates of apathy in depression evidenced in this study may contribute to characterize different phenotypes of depression., Competing Interests: Declaration of competing interest The authors don't have any conflict of interest related to this research work., (Copyright © 2022. Published by Elsevier Ltd.)

Background: Resistance to fibrinolysis, levels of procoagulant/antifibrinolytic neutrophil extracellular traps (NETs), and the severity of acute ischemic stroke (AIS) are increased by COVID-19. Whether NETs are components of AIS thrombi from COVID-19 patients and whether COVID-19 impacts the susceptibility of these thrombi to thrombolytic treatments remain unknown, however., Objectives: We aimed to characterize AIS thrombi from COVID-19 patients by immunohistology and to compare their response to thrombolysis to that of AIS thrombi from non-COVID-19 patients., Patients/methods: For this monocentric cohort study, 14 thrombi from COVID-19 AIS patients and 16 thrombi from non-COVID-19 patients, all recovered by endovascular therapy, were analyzed by immunohistology or subjected to ex vivo thrombolysis by tissue-type plasminogen (tPA)/plasminogen., Results: COVID-19 AIS thrombi were rich in neutrophils and contained NETs, but not spike protein. Thrombolysis assays revealed a mean resistance profile to tPA/plasminogen of COVID-19 AIS thrombi similar to that of non-COVID-19 AIS thrombi. The addition of DNase 1 successfully improved thrombolysis by potentiating fibrinolysis irrespective of COVID-19 status. Levels of neutrophil, NETs, and platelet markers in lysis supernatants were comparable between AIS thrombi from non-COVID-19 and COVID-19 patients., Conclusions: These results show that COVID-19 does not impact NETs content or worsen fibrinolysis resistance of AIS thrombi, a therapeutic hurdle that could be overcome by DNase 1 even in the context of SARS-CoV-2 infection., (© 2022 International Society on Thrombosis and Haemostasis.)

Background: Major depressive disorder (MDD) is characterized by impaired cortical-subcortical functional connectivity. Apathy adds to functional impairment, but its cerebral basis in MDD remains unknown. Our objective was to describe impairments in functional connectivity during emotional processing in MDD (with varying levels of congruency and attention), and to determine their correlation with apathy., Methods: We used the Variable Attention Affective Task during functional MRI, followed by diffusion-weighted MRI, to assess 55 right-handed women (30 with MDD and 25 healthy controls) between September 2012 and February 2015. We estimated functional connectivity using generalized psychophysiologic interaction and anatomic connectivity with tract-based spatial statistics. We measured apathy using the Apathy Evaluation Scale., Results: We found decreased functional connectivity between the left amygdala and the left anterior cingulate cortex (ACC) during negative stimuli in participants with MDD (t54 = 4.2; p = 0.035, family-wise error [FWE]-corrected). During high-attention stimuli, participants with MDD showed reduced functional connectivity between the right dorsolateral prefrontal cortex (dlPFC) and the right ACC (t54 = 4.06, pFWE = 0.02), but greater functional connectivity between the right dlPFC and the right amygdala (t54 = 3.35, p = 0.048). Apathy was associated with increased functional connectivity between the right dlPFC and the right ACC during high-attention stimuli (t28 = 5.2, p = 0.01) and increased fractional anisotropy in the right posterior cerebellum, the anterior and posterior cingulum and the bilateral internal capsule (all pFWE < 0.05)., Limitations: Limitations included a moderate sample size, concomitant antidepressant therapy and no directed connectivity., Conclusion: We found that MDD was associated with impairments in cortical-subcortical functional connectivity during negative stimuli that might alter the recruitment of networks engaged in attention. Apathy-related features suggested networks similar to those observed in degenerative disorders, but possible different mechanisms., Competing Interests: G. Robert received funding for scientific talks from Janssen and Otsuka-Lundbeck (once each in the last 5 years). None of these were related to the current work. No other competing interests declared., (© 2021 Joule Inc. or its licensors.)

Rationale: Mechanical thrombectomy (MT) using a stent retriever (SR) device is currently the recommended treatment in ischemic stroke due to anterior circulation large vessel occlusion. Combining contact aspiration (CA) with SR is a promising new treatment, although it was not found to be superior to SR alone as first-line treatment for achieving successful reperfusion., Aim: To determine whether endovascular treatment combining first-line use of CA and SR is more efficient than SR alone., Methods: The ASTER 2 clinical trial is a prospective, randomized, multicenter, open-label trial with a blinded endpoint. We included patients admitted with suspected anterior circulation ischemic stroke secondary to large vessel occlusion <8 hours from symptom onset. They were randomly allocated in a 1:1 ratio to one of two treatment groups (combined CA and SR or SR alone). In the case of failure of the assigned technique after three attempts, other adjunctive techniques were applied., Study Outcome: The primary outcome is the rate of successful/complete reperfusion (modified Thrombolysis In Cerebral Infarction (mTICI) score 2c/3) after the entire endovascular procedure. Secondary outcomes include reperfusion rates after the assigned first-line intervention alone and at the end of the procedure, procedural times, change in NIH Stroke Scale score at 24 hours, intracerebral hemorrhage at 24 hours, procedure-related serious adverse events, the modified Rankin Scale score, and all-cause mortality at 90 days and 1 year. The cost effectiveness of the two procedures will also be analyzed., Discussion: This is the first head-to-head randomized trial to directly compare the efficacy of the combined use of CA and SR versus SR alone. This prospective trial aims to demonstrate the synergistic effects of CA and SR devices in first-line endovascular treatment., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Background and Purpose: The reasons for poor clinical outcome after thrombectomy for acute stroke, concerning around half of all patients, are misunderstood. We developed a hierarchic algorithm based on DWI to better identify patients at high risk of disability., Materials and Methods: Our single-center, retrospective study included consecutive patients with acute ischemic stroke who underwent thrombectomy for large anterior artery occlusion and underwent pretreatment DWI. The primary outcome was the mRS at 3 months after stroke onset. Multivariable regression was used to identify independent clinical and imaging predictors of poor prognosis (mRS > 2) at 3 months, and a hierarchic algorithm predictive of disability was developed., Results: A total of 149 patients were analyzed. In decreasing importance, DWI lesion volume of >80 mL, baseline NIHSS score of >14, age older than 75 years, and time from stroke onset to groin puncture of >4 hours were independent predictors of poor prognosis. The predictive hierarchic algorithm developed from the multivariate analysis predicted the risk of disability at 3 months for up to 100% of patients with a high predictive value. The area under the receiver operating characteristic curve was 0.87., Conclusions: The DWI-based hierarchic algorithm we developed is highly predictive of disability at 3 months after thrombectomy and is easy to use in routine practice., (© 2020 by American Journal of Neuroradiology.)

Background: Evidence regarding whether imaging can be used effectively to select patients for endovascular thrombectomy (EVT) is scarce. We aimed to investigate the association between baseline imaging features and safety and efficacy of EVT in acute ischaemic stroke caused by anterior large-vessel occlusion., Methods: In this meta-analysis of individual patient-level data, the HERMES collaboration identified in PubMed seven randomised trials in endovascular stroke that compared EVT with standard medical therapy, published between Jan 1, 2010, and Oct 31, 2017. Only trials that required vessel imaging to identify patients with proximal anterior circulation ischaemic stroke and that used predominantly stent retrievers or second-generation neurothrombectomy devices in the EVT group were included. Risk of bias was assessed with the Cochrane handbook methodology. Central investigators, masked to clinical information other than stroke side, categorised baseline imaging features of ischaemic change with the Alberta Stroke Program Early CT Score (ASPECTS) or according to involvement of more than 33% of middle cerebral artery territory, and by thrombus volume, hyperdensity, and collateral status. The primary endpoint was neurological functional disability scored on the modified Rankin Scale (mRS) score at 90 days after randomisation. Safety outcomes included symptomatic intracranial haemorrhage, parenchymal haematoma type 2 within 5 days of randomisation, and mortality within 90 days. For the primary analysis, we used mixed-methods ordinal logistic regression adjusted for age, sex, National Institutes of Health Stroke Scale score at admission, intravenous alteplase, and time from onset to randomisation, and we used interaction terms to test whether imaging categorisation at baseline modifies the association between treatment and outcome. This meta-analysis was prospectively designed by the HERMES executive committee but has not been registered., Findings: Among 1764 pooled patients, 871 were allocated to the EVT group and 893 to the control group. Risk of bias was low except in the THRACE study, which used unblinded assessment of outcomes 90 days after randomisation and MRI predominantly as the primary baseline imaging tool. The overall treatment effect favoured EVT (adjusted common odds ratio [cOR] for a shift towards better outcome on the mRS 2·00, 95% CI 1·69-2·38; p<0·0001). EVT achieved better outcomes at 90 days than standard medical therapy alone across a broad range of baseline imaging categories. Mortality at 90 days (14·7% vs 17·3%, p=0·15), symptomatic intracranial haemorrhage (3·8% vs 3·5%, p=0·90), and parenchymal haematoma type 2 (5·6% vs 4·8%, p=0·52) did not differ between the EVT and control groups. No treatment effect modification by baseline imaging features was noted for mortality at 90 days and parenchymal haematoma type 2. Among patients with ASPECTS 0-4, symptomatic intracranial haemorrhage was seen in ten (19%) of 52 patients in the EVT group versus three (5%) of 66 patients in the control group (adjusted cOR 3·94, 95% CI 0·94-16·49; p interaction =0·025), and among patients with more than 33% involvement of middle cerebral artery territory, symptomatic intracranial haemorrhage was observed in 15 (14%) of 108 patients in the EVT group versus four (4%) of 113 patients in the control group (4·17, 1·30-13·44, p interaction =0·012)., Interpretation: EVT achieves better outcomes at 90 days than standard medical therapy across a broad range of baseline imaging categories, including infarcts affecting more than 33% of middle cerebral artery territory or ASPECTS less than 6, although in these patients the risk of symptomatic intracranial haemorrhage was higher in the EVT group than the control group. This analysis provides preliminary evidence for potential use of EVT in patients with large infarcts at baseline., Funding: Medtronic., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background: Susceptibility-weighted imaging (SWI) of brain tumors provides information about neoplastic vasculature and intratumoral micro- and macrobleedings. Low- and high-grade gliomas can be distinguished by SWI due to their different vascular characteristics. Fractal analysis allows for quantification of these radiological differences by a computer-based morphological assessment of SWI patterns., Objective: To show the feasibility of SWI analysis on 3-T magnetic resonance imaging to distinguish different kinds of brain tumors., Methods: Seventy-eight patients affected by brain tumors of different histopathology (low- and high-grade gliomas, metastases, meningiomas, lymphomas) were included. All patients underwent preoperative 3-T magnetic resonance imaging including SWI, on which the lesions were contoured. The images underwent automated computation, extracting 2 quantitative parameters: the volume fraction of SWI signals within the tumors (signal ratio) and the morphological self-similar features (fractal dimension [FD]). The results were then correlated with each histopathological type of tumor., Results: Signal ratio and FD were able to differentiate low-grade gliomas from grade III and IV gliomas, metastases, and meningiomas (P < .05). FD was statistically different between lymphomas and high-grade gliomas (P < .05). A receiver-operating characteristic analysis showed that the optimal cutoff value for differentiating low- from high-grade gliomas was 1.75 for FD (sensitivity, 81%; specificity, 89%) and 0.03 for signal ratio (sensitivity, 80%; specificity, 86%)., Conclusion: FD of SWI on 3-T magnetic resonance imaging is a novel image biomarker for glioma grading and brain tumor characterization. Computational models offer promising results that may improve diagnosis and open perspectives in the radiological assessment of brain tumors., Abbreviations: FD, fractal dimensionSR, signal ratioSWI, susceptibility-weighted imaging.

There is increasing evidence supporting the existence of a link between income inequalities and health outcomes. The main purpose of this article is to test whether economic inequalities are associated with poor population health in Latin American countries. Multi-country data from 1970 to 2012 were used to assess this question. The results show that the Gini coefficient has a strong correlation with health outcomes. Moreover, multiple linear regression analysis using fixed effects shows that after controlling for gross national income per capita, literacy rate, and health expenditure, the Gini coefficient is independently negatively associated with health outcomes. In Latin American countries, for every percentage point increase in the Gini coefficient, the infant mortality rate grows by 0.467 deaths per 1,000 live births, holding all other variables constant. Additionally, an ordinary least squares estimation model suggests that countries that do not use International Monetary Fund loans perform better on health outcomes. These findings should alert policymakers, elected officials, and the public of the need to fight income inequalities and rethink the role of international financial institutions that dictate state policies., (© Australian Council for Educational Research 2016.)

Background and Purpose: Patients treated with coiling are often followed by MR angiography. Our objective was to assess the inter- and intraobserver agreement in diagnosing aneurysm remnants and recurrences by using multimodality imaging, including TOF MRA., Materials and Methods: A portfolio composed of 120 selected images from 56 patients was sent to 15 neuroradiologists from 10 institutions. For each case, raters were asked to classify angiographic results (3 classes) of 2 studies (32 MRA-MRA and 24 DSA-MRA pairs) and to provide a final judgment regarding the presence of a recurrence (no, minor, major). Six raters were asked to independently review the portfolio twice. A second study, restricted to 4 raters having full access to all images, was designed to validate the results of the electronic survey., Results: The proportion of cases judged to have a major recurrence varied between 16.1% and 71.4% (mean, 35.0% ± 12.7%). There was moderate agreement overall (κ = 0.474 ± 0.009), increasing to nearly substantial (κ = 0.581 ± 0.014) when the judgment was dichotomized (presence or absence of a major recurrence). Agreement on cases followed-up by MRA-MRA was similarly substantial (κ = 0.601 ± 0.018). The intrarater agreement varied between fair (κ = 0.257 ± 0.093) and substantial (κ= 0.699 ± 0.084), improving with a dichotomized judgment concerning MRA-MRA comparisons. Agreement was no better when raters had access to all images., Conclusions: There is an important variability in the assessment of angiographic outcomes of endovascular treatments. Agreement on the presence of a major recurrence when comparing 2 MRA studies or the MRA with the last catheter angiographic study can be substantial., (© 2016 by American Journal of Neuroradiology.)

Objectives: Arterial spin labelling (ASL) is a promising MRI sequence that allows noninvasive detection of cortical perfusion alterations in neurodegenerative disorders, but its interpretation remains difficult at an individual level. In this work, a cortical surface-based projection of ASL maps was applied in patients with early-onset Alzheimer's disease (EOAD) to improve the image quality and visual representation of perfusion data., Methods: Eighteen patients referred from the reference centre for EOAD were assessed by MRI with ASL sequences. Data processing was applied on each examination including correction of partial volume effects and cortical projection of preprocessed ASL data. Cortical segmentation and perfusion display were qualitatively analyzed according to a three-point scale., Results: All examinations were suitable for complete data processing. Quality of segmentation and of cortical surface-based perfusion maps was scored as optimal in 72 % in both cases. Cortical surface-based ASL maps provided a more global view than single slices and an accurate approach of brain perfusion in EOAD patients., Conclusion: Cortical surface-based analysis of ASL maps is technically feasible with a good image quality and may enable significant improvement in the detection of focal perfusion alterations in neurodegenerative disorders in the real-life clinical setting., Key Points: • Arterial spin labelling is a promising sequence for assessing Alzheimer's disease. • Optimization of ASL brain perfusion image quality is crucial for image interpretation. • Cortical surface-based analysis may improve detection of perfusion alterations in a real-life clinical setting.

Background: Excluding a cerebral venous thrombosis (CVT) through imaging is a frequent request in the emergency setting. This assessment often starts by an unenhanced brain computed tomography (CT)., Purpose: Re-evaluate the value of spontaneous hyperdensity of CVT on helical unenhanced brain CT., Methods: Multicentric retrospective study on CVT probability based on visual assessment of spontaneous hyperdensity of cerebral venous system, performed by four blinded radiologists, individually then collectively, on a population including 14 helical unenhanced brain CTs with CVT and 102 unenhanced brain CTs without CVT (all confirmed by CT or magnetic resonance [MR] venography). Exclusion criteria: no DICOM image, symptoms >15 days, CVT indirect signs on unenhanced CT. A fifth radiologist set 768 regions of interest to measure and to compare the density within the normal venous sinuses and the CVTs., Results: After consensus reading, sensitivity of this sign for CVT diagnosis was 100%, specificity 95.1%, and negative predictive value (NPV) 100%, with high individual NPV (99-100%). Area under the receiver-operating characteristic curve was 0.992 after consensus (0.976-0.986 individually). The spontaneous density was significantly different (P <0.05) between normal sinuses and CVTs, with a density >70 HU reported only within the CVTs, except for the horizontal part of the superior sagittal sinus (hSSS)., Conclusion: The dense triangle sign on helical unenhanced brain CT has an excellent NPV to exclude a sinus thrombosis during the first 2 weeks. However, we believe that visual assessment of spontaneous hyperdensity is not sufficient for the diagnosis of CVT, with possible false-positive of the hSSS on unenhanced CT., (© The Foundation Acta Radiologica 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.)

Purpose: Dynamic contrast-enhanced imaging provides unique physiological information, notably the endothelial permeability (K(trans)), and may improve the diagnosis and management of multiple pathologies. Current acquisition methods provide limited spatial-temporal resolution and field-of-view, often preventing characterization of the entire pathology and precluding measurement of the arterial input function. We present a method for highly accelerated dynamic imaging and demonstrate its utility for dynamic contrast-enhanced modeling., Methods: We propose a novel Poisson ellipsoid sampling scheme and enforce multiple spatial and temporal l1-norm constraints during image reconstruction. Retrospective and prospective analyses were performed to validate the approach., Results: Retrospectively, no mean bias or diverging trend was observed as the acceleration rate was increased from 3× to 18×; less than 10% error was measured in K(trans) at any individual rates in this range. Prospectively accelerated images at a rate of 36× enabled full brain coverage with 0.94 × 0.94 × 1.9 mm(3) spatial and 4.1 s temporal resolutions. Images showed no visible degradation and provided accurate K(trans) values when compared to a clinical population., Conclusion: Highly accelerated dynamic MRI using compressed sensing and parallel imaging provides accurate permeability modeling and enables full brain, high resolution acquisitions., (Copyright © 2013 Wiley Periodicals, Inc.)

Purpose: Diffusion tensor imaging permits study of white matter fibre bundles; however, its main limitation is lack of validation on anatomical data, especially in crossing fibre regions. Our study aimed to compare four deterministic tractography algorithms used in clinical routine. We studied the corticospinal tract, the bundle mediating voluntary movement. Our study seeks to evaluate tractography provided by algorithms through comparative analysis by expert neuroradiologists., Methods: MRI data from 15 right-handed volunteers (30.8 years) were studied. Regions of interest (ROIs) were segmented on morphological and functional MRI. Diffusion weighted images (15 directions) were performed, then for each voxel the tensor was estimated. Tractography of the corticospinal tract was performed using four fibre-tracking algorithms. Three numerical integration methods Euler, Runge-Kutta second (RK2) and fourth order (RK4), and a tensor deflection method (TEND). Quantitative measurement was performed. Qualitative evaluation was carried out by two expert neuroradiologists using Kappa test concordance., Results: For the quantitative aspect, only RK2 and TEND presented no significant difference concerning the number of fibres (p = 0.58). There was no difference between right and left side for each algorithm. Regarding the qualitative aspects, there was a lack of fibres from the ventrolateral part of the functional ROIs. Comparison by expert neuroradiologists revealed low rather than high concordance. The algorithm ranked first was RK2 according to expert preferences., Conclusions: Different algorithms used in clinical routine failed to show realistic anatomical bundles. The most mathematically robust algorithm was not selected, nor was the algorithm defining more fibres. Validation of anatomical data provided by tractography remains a challenge.

Transcranial magnetic stimulation (TMS) is a non-invasive technique used in the treatment of major depression. Meta-analyses have shown that it is more efficient than a placebo and that its efficacy is enhanced by the optimum tuning of stimulation parameters. However, the stimulation target, the dorsolateral prefrontal cortex (DLPFC), is still located using an inaccurate method. In this study, a neuronavigation system was used to perform a comprehensive quantification of target localization errors. We identified and quantified 3 sources of error in the standard method: cap repositioning, interexpert variability in coil positioning and distance between the stimulated point and the expected target. For cap repositioning, the standard deviation was lower than 5mm in the 3 axes. For interexpert variability in coil positioning, the spatial dispersion of the points was higher than 10mm in 2 of the 3 axes. For interindividual anatomical variability, the distance between the actual "reference" DLPFC and its standard determination was greater than 20mm for 54% of the subjects, while one subject out of eleven was correctly targeted which means 10mm or less from the reference. Results showed that interindividual anatomical variability and interexpert variability were the two main sources of error using the standard method. Results demonstrate that a neuronavigation system is mandatory to conduct reproducible and reliable studies., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

New MR imaging protocols enable visualization of brain structures. However, for dedicated clinical applications such as targeting deep brain stimulation (DBS), a more accurate localization requires the use of atlases. We developed a three-dimensional digitized mono-subject anatomical template of the human brain based on 3-T magnetic resonance images (MRI). By averaging 15 registered T1 image acquisitions, we have shown that the final image corresponds to an optimal image, limited by the performance of the 3-T MR machine. We compared different preprocessing workflows for template construction. With the optimal strategy, along with validated existing processing methods, one T1 template and one T1-T2 mixing template were created in order to improve visualization of spatially complex deep structures. Reduction of voxel size to 0.25 mm(3) was also advantageous to observe fine structures and white matter/gray matter intensity crossings. Results demonstrated that such a template also improved inter-patient registration for population comparison in DBS. These MR templates are made freely available to our community (http://www.vmip.org/mritemplate) to serve as a reference for neuroimage processing methods.

Background: Endoscopic third ventriculostomy is an effective procedure for treating obstructive (noncommunicating) hydrocephalus as an alternative to ventricular shunt placement., Case: Five pregnant women undergoing endoscopic third ventriculostomy as treatment for newly diagnosed acute obstructive hydrocephalus (n=2) or in cases of malfunction of a preexisting ventriculoperitoneal shunt (n=3) are presented., Conclusion: Endoscopic third ventriculostomy may be preferred to ventricular shunt placement as the initial mode of treatment for pregnant patients with newly diagnosed obstructive hydrocephalus as well as in cases of malfunction of a preexisting shunt.

As logical consequence of a series of basic research studies on human femoral bones with unipodal support and under static stress, performed with physicomathematic modelling methods (finite-elements method) then confirmed by direct visualization of deformations resulting from such stress using holographic interferometry, the authors have worked on the definition of an optimized and individualized hip prosthesis. Thick CT sections digitized with a table and entered into a specially programmed computer allowed three-dimensional modelling of the femur as a volume, i.e. with its external contour and its medullary canal, and therefore of the implantable space. The prosthesis was then defined taking a number of hypotheses into account: necessity to regularize cortical bone spicules inside spongious bone, which are so often present opposite the rough line, partial machining at the level of the calcar, reduced tail length, presence or absence of collar. Thus an optimized and individualized prosthesis was defined. A prototype corresponding to a given femoral bone could then have been produced. However, the authors found it preferable to use simulation with computer synthetic images to check easy insertion and removal.

The biomechanics-, engineering- and anatomy-oriented authors studied the craniofacial structures emphasizing their perfect adaptation to stresses developing during mastication or related to head statics and motions. For a better understanding of the biomechanics of the basis of the skull and face, attention is consistently drawn to solutions used in state-of-the-art engineering, such as aeronautics, in consideration that such solutions as are chosen by engineers are often--consciously or not--copied from nature.

Previous studies employing a plane "model" on the hemi-mandible confirmed the concept of a "bees-nest" structure of the mandible. As this plane model did not permit demonstration of maximal zones of iso-stress in the horizontal rami, the whole mandible was examined by means of a three-dimensional model. This gave more precise information, and thus produced more realistic results confirming previous findings. This new reliable type of model can be employed for any such exploratory procedure, and in studies totally different from those for which it was developed.

In face of the double reflex of fascination and defiance which is right away created by statistical methods by computers, the authors have attempted by means of precise examples to demystify these methods by recalling: 1) That computer statistics can be defined as the association of a service and a machine, the combination should be considered as an instrument and only an instrument. 2) That the application of computer statistics to odonto-stomatological research of course evidently enables the resolution of problems which would be otherwise insoluble, but above all considerably enlarges the field of research by rendering visible phenomena which would otherwise remain hidden. In this way, statistical methods by computer can be compared with the microscope; a low magnification with the optical microscope justifies only an overall view of the section while changing to higher magnifications permits the demonstration of details which would remain unsuspected. Use of the electromicroscope opens up another world for research. 3) In the same way as the biologist who uses the microscope, if he knows the principle of it is not in so far a specialist in optics, neither does the research woker who uses statistics necessarily have to be a trained statistician, on the one condition that evidently he disposes of professional computer logistics. This is the case of the ACB (Nantes) rush technical units, who cosigned this work, where the engineers who pose the problems to be resolved and emit the working hypotheses from the results supplied by the statistical studies are not the same people who carry out these very studies. 4) An essential fact, the research worker's independance is complete, only he can pose the problems and emit the hypothesis from the correlation, i. e. point of fact concomitance between the various isolated parameters. It therefore does not seem that weighty statistical techniques presently occupy the place of choice which should be theirs in stomatological research and more particularly in research concerning growth and development of the face where their use seems to be electively implied in face of the number and complexity of the parameters looked at.

Acquired maxillo-facial deformities and in particular those related to problems of facial expression are nevertheless influenced by certain hereditary factors, amongst which the constitutional type or the temperament of the individual play a major role. Morpho-psychology (L. Corman), or the art of relating physical details (especially the shape and characteristics of the face) with psychological state demonstrates correlations between the type of deformity and that of the temperament and explains them. After a brief review of the essential principles of morpho-psychology, the authors study a number of special morpho-psychological types presenting with a significant frequency maxillo-facial deformities, themselves special, and which for this reason they call "morpho-psychological types with a high orthodontic risk". They conclude that it would appear that insufficient importance is attributed at present to psychological factors in the aetiopathogenesis of dysmorphoses and feel that an overall approach to the deformed child is indispensable to progress in the specialty.