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BACKGROUND AND OBJECTIVES: Cocaine is a highly addictive substance, and with no approved medication for cocaine use disorder (CUD), leading to a heavy burden. Despite validated psychosocial treatments, relapse rates after detoxification are very high in CUD. Few consistent factors can predict abstinence after detoxification. Our study, therefore, aimed at identifying factors predicting abstinence among CUD patients after inpatient detoxification. METHODS: Eighty-one CUD inpatients were included during detoxification and characterized for clinical and sociodemographic data at baseline and at a follow-up of 3 months after discharge, including a standard measure of their abstinence duration from cocaine. We performed Cox univariate analyzes to determine the factors associated with abstinence maintenance, followed by a multivariate Cox regression to identify independent predictors. RESULTS: Abstinence maintenance was shorter in patients injecting cocaine (hazard ratio [HR] = 5.16, 95% confidence interval [CI]: 2.01-13.27, p < .001) and using cocaine heavily in the month before inclusion (HR = 1.03, 95% CI: 1.00-1.06, p = .046). Conversely, abstinence maintenance was longer in patients with longer inpatient detoxification stays (HR = 0.96, 95% CI: 0.94-0.99, p = .015) and prescribed with selective serotonin reuptake inhibitors (SSRIs) (HR = 0.30, 95% CI: 0.16-0.56, p < .001). DISCUSSION AND CONCLUSIONS: Patients with severe CUD may require longer inpatient stays to achieve abstinence. Regarding SSRI prescription, more specific studies are needed to provide stronger recommendations about their use in clinical practice. SCIENTIFIC SIGNIFICANCE: Our findings suggest several modifiable factors to improve inpatient treatment response in CUD. As there are no specific recommendations about the optimal duration of inpatient stay, our results could pave the way for evidence-based guidelines.
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BACKGROUND: The objective of breast reconstruction (BR) is to erase the after-effects of total mastectomy by allowing patients to restore their breast shape. The aim of our study was to investigate the body map integration of different types of BR using functional magnetic resonance (fMRI). PATIENTS AND METHODS: We prospectively enrolled all women undergoing BR for breast cancer to the Remasco study (NCT02553967). Participants were categorized into four groups according to the standard of care they required: immediate BR (IBR), delayed BR (DBR), flap (autologous), or implant BR. Each patient performed sensorimotor tasks during the fMRI acquisition. RESULTS: Data of 38 patients were analyzed. We identified the cingulate region as the area of interest in the brain. In the case of DBR, the brain area activated during palpation of the total mastectomy scar (before BR) was different from the brain area activated during palpation of the reconstructed breast (Brodmann areas 31 versus 32). Palpation of the native breast and reconstructed breast activated the same Brodmann area 32. Comparing the brain activation signal during palpation of the native breast and the reconstructed breast did not reveal any significant difference in the overall population (P = 0.41) or in the groups: autologous (P = 0.32), implant (P = 0.10), IBR (P = 0.72), or DBR (P = 0.10). CONCLUSIONS: This experimental study allowed us to describe and understand the brain plasticity processes that accompany BR. The results suggest that the reconstructed breast is integrated into the body schema, regardless of the type of BR or the timing.
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Neoplasias da Mama , Mamoplastia , Imagem Corporal , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Feminino , Humanos , Imageamento por Ressonância Magnética , Mamoplastia/métodos , MastectomiaRESUMO
OBJECTIVES: QyScore® is an imaging analysis tool certified in Europe (CE marked) and the US (FDA cleared) for the automatic volumetry of grey and white matter (GM and WM respectively), hippocampus (HP), amygdala (AM), and white matter hyperintensity (WMH). Here we compare QyScore® performances with the consensus of expert neuroradiologists. METHODS: Dice similarity coefficient (DSC) and the relative volume difference (RVD) for GM, WM volumes were calculated on 50 3DT1 images. DSC and the F1 metrics were calculated for WMH on 130 3DT1 and FLAIR images. For each index, we identified thresholds of reliability based on current literature review results. We hypothesized that DSC/F1 scores obtained using QyScore® markers would be higher than the threshold. In contrast, RVD scores would be lower. Regression analysis and Bland-Altman plots were obtained to evaluate QyScore® performance in comparison to the consensus of three expert neuroradiologists. RESULTS: The lower bound of the DSC/F1 confidence intervals was higher than the threshold for the GM, WM, HP, AM, and WMH, and the higher bounds of the RVD confidence interval were below the threshold for the WM, GM, HP, and AM. QyScore®, compared with the consensus of three expert neuroradiologists, provides reliable performance for the automatic segmentation of the GM and WM volumes, and HP and AM volumes, as well as WMH volumes. CONCLUSIONS: QyScore® represents a reliable medical device in comparison with the consensus of expert neuroradiologists. Therefore, QyScore® could be implemented in clinical trials and clinical routine to support the diagnosis and longitudinal monitoring of neurological diseases. KEY POINTS: ⢠QyScore® provides reliable automatic segmentation of brain structures in comparison with the consensus of three expert neuroradiologists. ⢠QyScore® automatic segmentation could be performed on MRI images using different vendors and protocols of acquisition. In addition, the fast segmentation process saves time over manual and semi-automatic methods. ⢠QyScore® could be implemented in clinical trials and clinical routine to support the diagnosis and longitudinal monitoring of neurological diseases.
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Doenças do Sistema Nervoso Central , Leucoaraiose , Doenças Neurodegenerativas , Substância Branca , Atrofia/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Humanos , Leucoaraiose/patologia , Imageamento por Ressonância Magnética/métodos , Doenças Neurodegenerativas/patologia , Reprodutibilidade dos Testes , Substância Branca/diagnóstico por imagem , Substância Branca/patologiaRESUMO
INTRODUCTION: Blood-based biomarkers are the next challenge for Alzheimer's disease (AD) diagnosis and prognosis. METHODS: Mild cognitive impairment (MCI) participants (N = 485) of the BALTAZAR study, a large-scale longitudinal multicenter cohort, were followed-up for 3 years. A total of 165 of them converted to dementia (95% AD). Associations of conversion and plasma amyloid beta (Aß)1-42 , Aß1-40 , Aß1-42 /Aß1-40 ratio were analyzed with logistic and Cox models. RESULTS: Converters to dementia had lower level of plasma Aß1-42 (37.1 pg/mL [12.5] vs. 39.2 [11.1] , P value = .03) and lower Aß1-42 /Aß1-40 ratio than non-converters (0.148 [0.125] vs. 0.154 [0.076], P value = .02). MCI participants in the highest quartile of Aß1-42 /Aß1-40 ratio (>0.169) had a significant lower risk of conversion (hazard ratio adjusted for age, sex, education, apolipoprotein E ε4, hippocampus atrophy = 0.52 (95% confidence interval [0.31-0.86], P value = .01). DISCUSSION: In this large cohort of MCI subjects we identified a threshold for plasma Aß1-42 /Aß1-40 ratio that may detect patients with a low risk of conversion to dementia within 3 years.
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Doença de Alzheimer , Disfunção Cognitiva , Humanos , Peptídeos beta-Amiloides , Disfunção Cognitiva/diagnóstico , Doença de Alzheimer/diagnóstico , Apolipoproteína E4 , Biomarcadores , Fragmentos de Peptídeos , Proteínas tau , Progressão da DoençaRESUMO
PURPOSE: Intraoperative MRI (iMRI) offers the possibility of acquiring intraoperatively real-time images that will guide neurosurgeons when removing brain tumors. The objective of this study was to report the existence of FLAIR abnormalities on iMRI that may occur on the margin of a brain resection and may lead to misdiagnosis of residual tumor. METHODS: We retrospectively analyzed intraoperative MRI (iMRI) in 21 consecutive patients who underwent surgery for a low-grade glioma. Two readers independently reviewed iMRI images to search for the presence of a FLAIR hyperintensity surrounding the surgical cavity. For each patient, they were instructed to characterize FLAIR abnormalities on the margins of the resected area as (1) no FLAIR abnormality; (2) "linear FLAIR hyperintensity (LFH)", when a<5mm linear FLAIR hyperintensity was present; or (3) "nodular FLAIR hyperintensity (NFH)", in the case of a thick and nodular FLAIR hyperintensity. RESULTS: LFH were present on at least one surgical margin of one third of the patients analyzed with iMRI, and vanished on follow-up MRI, confirming its transient condition; whereas NFH were linked to persistence of pre-surgical abnormalities, such as residual tumor as confirmed or by histopathological analysis of a second surgery or by its remnant on follow-up MRI. CONCLUSION: Linear FLAIR hyperintensities can be present on surgical margins analyzed by iMRI and should not be mistaken for residual tumor.
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Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Glioma/diagnóstico por imagem , Glioma/cirurgia , Humanos , Imageamento por Ressonância Magnética , Neoplasia Residual/diagnóstico por imagem , Estudos RetrospectivosRESUMO
Internal jugular vein (IJV) thrombosis is mainly related to central venous catheter, malignancy, and ovarian hyperstimulation syndrome. We report a case of IJV thrombosis possibly related to IJV compression between the styloid process and the first cervical vertebra (C1) transverse process. To support this hypothesis, we perform radiological assessment of the IJV and examine its relationship with the styloid process and C1 transverse process in 34 controls. Our results showed a strong correlation between IJV diameter and styloid process-C1 transverse process distance. Compared to control subjects, our patient had a short styloid process-C1 transverse process distance, which suggests its involvement in IJV thrombosis.
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Veias Jugulares , Osso Temporal , Trombose Venosa/etiologia , Anticoagulantes/administração & dosagem , Constrição Patológica , Humanos , Veias Jugulares/diagnóstico por imagem , Masculino , Osso Temporal/diagnóstico por imagem , Resultado do Tratamento , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/tratamento farmacológico , Adulto JovemRESUMO
BACKGROUND: High-field intraoperative MRI (IoMRI) is part of the neurosurgical armamentarium to improve the extent of glioma resection (EOR). OBJECTIVE: To report our oncological and functional outcomes using IoMRI for neuronavigated glioma surgery. METHODS: In this prospective monocentric study, we reported 100 consecutive adult patients operated on for glioma using IoMRI with neuronavigation, under general anesthesia without intraoperative stimulation, from July 2014 to April 2017. The volumetric evaluation was based on the FLAIR hypersignal for non-enhancing tumors after Gadolinium infusion and on the T1 hypersignal after Gadolinium infusion for enhancing tumors. We evaluated the surgical workflow, the EOR and the clinical outcomes (using Karnofsky performance score (KPS)). RESULTS: Sixty-nine patients underwent one IoMRI, and 31 from two IoMRI controls. At first IoMRI, the median tumor residue was higher in the FLAIR group than in the T1G+ group whereas no more difference was reported after the second IoMRI between the 2 groups (p = 0.56). Additional resection was performed 6 times more frequently in the FLAIR group (OR = 5.7, CI (1.9-17)). The median EOR was 100% (IQR, 93.6-100) whatever the tumor type (first surgery or recurrence) and location. Higher residues were reported only in the insula area (p = 0.004). The median KPS was 90 (IQR, 80-100) at discharge, 3, 6 and 12 months after surgery, with no statistical difference between low- and high-grade gliomas (p = 0.34). CONCLUSION: IoMRI neuronavigated surgery provided maximal EOR whatever the type of glioma and location. IoMRI was all the more useful for non- or minimally enhancing tumors. The step by step surgical resection, introducing the concept of "staged volume" surgery, ensured a high security for the surgeon and low permanent morbidity for the patients.
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Neoplasias Encefálicas/cirurgia , Glioma/cirurgia , Imageamento por Ressonância Magnética/métodos , Monitorização Intraoperatória/métodos , Neuronavegação/métodos , Complicações Pós-Operatórias/epidemiologia , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico por imagem , Feminino , Glioma/diagnóstico por imagem , Humanos , Avaliação de Estado de Karnofsky , Masculino , Pessoa de Meia-Idade , Neoplasia Residual/diagnóstico por imagem , Neuronavegação/efeitos adversos , Complicações Pós-Operatórias/patologiaRESUMO
INTRODUCTION: Diagnostic relevance of plasma amyloid ß (Aß) for Alzheimer's disease (AD) process yields conflicting results. The objective of the study was to assess plasma levels of Aß42 and Aß40 in amnestic mild cognitive impairment (MCI), nonamnestic MCI, and AD patients and to investigate relationships between peripheral and central biomarkers. METHODS: One thousand forty participants (417 amnestic MCI, 122 nonamnestic MCI, and 501 AD) from the Biomarker of AmyLoïd pepTide and AlZheimer's diseAse Risk multicenter prospective study with cognition, plasma, cerebrospinal fluid (CSF), and magnetic resonance imaging assessments were included. RESULTS: Plasma Aß1-42 and Aß1-40 were lower in AD (36.9 [11.7] and 263 [80] pg/mL) than in amnestic MCI (38.2 [11.9] and 269 [68] pg/mL) than in nonamnestic MCI (39.7 [10.5] and 272 [52] pg/mL), respectively (P = .01 for overall difference between groups for Aß1-42 and P = .04 for Aß1-40). Globally, plasma Aß1-42 correlated with age, Mini-Mental State Examination, and APOE ε4 allele. Plasma Aß1-42 correlated with all CSF biomarkers in MCI but only with CSF Aß42 in AD. DISCUSSION: Plasma Aß was associated with cognitive status and CSF biomarkers, suggesting the interest of plasma amyloid biomarkers for diagnosis purpose.
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Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides/sangue , Biomarcadores , Disfunção Cognitiva/sangue , Disfunção Cognitiva/líquido cefalorraquidiano , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes de Estado Mental e Demência/estatística & dados numéricos , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
PURPOSE: Medial lobe temporal structures and more specifically the hippocampus play a decisive role in episodic memory. Most of the memory functional magnetic resonance imaging (fMRI) studies evaluate the encoding phase; the retrieval phase being performed outside the MRI. We aimed to determine the ability to reveal greater hippocampal fMRI activations during retrieval phase. MATERIALS AND METHODS: Thirty-five epileptic patients underwent a two-step memory fMRI. During encoding phase, subjects were requested to identify the feminine or masculine gender of faces and words presented, in order to encourage stimulus encoding. One hour after, during retrieval phase, subjects had to recognize the word and face. We used an event-related design to identify hippocampal activations. RESULTS: There was no significant difference between patients with left temporal lobe epilepsy, patients with right temporal lobe epilepsy and patients with extratemporal lobe epilepsy on verbal and visual learning task. For words, patients demonstrated significantly more bilateral hippocampal activation for retrieval task than encoding task and when the tasks were associated than during encoding alone. Significant difference was seen between face-encoding alone and face retrieval alone. CONCLUSIONS: This study demonstrates the essential contribution of the retrieval task during a fMRI memory task but the number of patients with hippocampal activations was greater when the two tasks were taken into account.
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Epilepsia/fisiopatologia , Epilepsia/psicologia , Hipocampo/fisiopatologia , Rememoração Mental/fisiologia , Adulto , Idoso , Mapeamento Encefálico , Epilepsia/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Adulto JovemRESUMO
Cognitive deficits are common in Parkinson's disease and we suspect that dysfunctions of connected brain regions can be the source of these deficits. The aim of the present study was to investigate changes in whole-brain intrinsic functional connectivity according to differences in cognitive profiles in Parkinson's disease. 119 participants were enrolled and divided into four groups according to their cognitive phenotypes (determined by a cluster analysis): (i) 31 cognitively intact patients (G1), (ii) 31 patients with only slight mental slowing (G2), (iii) 43 patients with mild to moderate deficits mainly in executive functions (G3), (iv) 14 patients with severe deficits in all cognitive domains (G4-5). Rs-fMRI whole-brain connectivity was examined by two complementary approaches: graph theory for studying network functional organization and network-based statistics (NBS) for exploring functional connectivity amongst brain regions. After adjustment for age, duration of formal education and center of acquisition, there were significant group differences for all functional organization indexes: functional organization decreased (G1 > G2 > G3 > G4-5) as cognitive impairment worsened. Between-group differences in functional connectivity (NBS corrected, P < 0.01) mainly concerned the ventral prefrontal, parietal, temporal and occipital cortices as well as the basal ganglia. In Parkinson's disease, brain network organization is progressively disrupted as cognitive impairment worsens, with an increasing number of altered connections between brain regions. We observed reduced connectivity in highly associative areas, even in patients with only slight mental slowing. The association of slowed mental processing with loss of connectivity between highly associative areas could be an early marker of cognitive impairment in Parkinson's disease and may contribute to the detection of prodromal forms of Parkinson's disease dementia. Hum Brain Mapp 38:1604-1621, 2017. © 2016 Wiley Periodicals, Inc.
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Mapeamento Encefálico , Encéfalo/patologia , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/patologia , Vias Neurais/diagnóstico por imagem , Doença de Parkinson/complicações , Idoso , Atenção/fisiologia , Encéfalo/diagnóstico por imagem , Transtornos Cognitivos/diagnóstico por imagem , Função Executiva , Feminino , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Masculino , Memória de Curto Prazo/fisiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Oxigênio/sangueRESUMO
Our purpose was to validate a reliable method to capture brain activity concomitant with hallucinatory events, which constitute frequent and disabling experiences in schizophrenia. Capturing hallucinations using functional magnetic resonance imaging (fMRI) remains very challenging. We previously developed a method based on a two-steps strategy including (1) multivariate data-driven analysis of per-hallucinatory fMRI recording and (2) selection of the components of interest based on a post-fMRI interview. However, two tests still need to be conducted to rule out critical pitfalls of conventional fMRI capture methods before this two-steps strategy can be adopted in hallucination research: replication of these findings on an independent sample and assessment of the reliability of the hallucination-related patterns at the subject level. To do so, we recruited a sample of 45 schizophrenia patients suffering from frequent hallucinations, 20 schizophrenia patients without hallucinations and 20 matched healthy volunteers; all participants underwent four different experiments. The main findings are (1) high accuracy in reporting unexpected sensory stimuli in an MRI setting; (2) good detection concordance between hypothesis-driven and data-driven analysis methods (as used in the two-steps strategy) when controlled unexpected sensory stimuli are presented; (3) good agreement of the two-steps method with the online button-press approach to capture hallucinatory events; (4) high spatial consistency of hallucinatory-related networks detected using the two-steps method on two independent samples. By validating the two-steps method, we advance toward the possible transfer of such technology to new image-based therapies for hallucinations. Hum Brain Mapp 38:4966-4979, 2017. © 2017 Wiley Periodicals, Inc.
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Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Alucinações/diagnóstico por imagem , Alucinações/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Adulto , Antipsicóticos/uso terapêutico , Mapeamento Encefálico/métodos , Feminino , Alucinações/tratamento farmacológico , Humanos , Masculino , Reprodutibilidade dos Testes , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/tratamento farmacológico , Esquizofrenia/fisiopatologiaRESUMO
OBJECTIVES: To determine the diagnostic accuracy of pharmacokinetic parameters measured by dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) in predicting the response of brain metastases to antineoplastic therapy in patients with lung cancer. METHODS: Forty-four consecutive patients with lung cancer, harbouring 123 newly diagnosed brain metastases prospectively underwent conventional 3-T MRI at baseline (within 1 month before treatment), during the early (7-10 weeks) and midterm (5-7 months) post-treatment period. An additional DCE MRI sequence was performed during baseline and early post-treatment MRI to evaluate baseline pharmacokinetic parameters (K trans, k ep, v e, v p) and their early variation (∆K trans, ∆k ep, ∆v e, ∆v p). The objective response was judged by the volume variation of each metastasis from baseline to midterm MRI. ROC curve analysis determined the best DCE MRI parameter to predict the objective response. RESULTS: Baseline DCE MRI parameters were not associated with the objective response. Early ∆K trans, ∆v e and ∆v p were significantly associated with the objective response (p = 0.02, p = 0.001 and p = 0.02, respectively). The best predictor of objective response was ∆v e with an area under the curve of 0.93 [95% CI = 0.87, 0.99]. CONCLUSIONS: DCE MRI and early ∆v e may be a useful tool to predict the objective response of brain metastases in patients with lung cancer. KEY POINTS: ⢠DCE MRI could predict the response of brain metastases from lung cancer ⢠∆v e was the best predictor of response ⢠DCE MRI could be used to individualize patients' follow-up.
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Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Pulmonares/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Neoplasias Encefálicas/secundário , Meios de Contraste/farmacocinética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROCRESUMO
The majority of patients with schizophrenia suffer from hallucinations. While the triple-network model, which includes the default mode network (DMN), the central executive network (CEN) and the salience network (SAL), has recently been applied to schizophrenia, how this framework could explain the emergence of hallucinations remains unclear. Therefore, complementary brain regions that have been linked to hallucinations, such as the left hippocampus, should also be considered and added to this model. Accordingly, the present study explored the effective connectivity across these four components (i.e., the quadripartite model) during the different stages of hallucinations. Twenty-five patients with schizophrenia participated in a single session of resting-state functional magnetic resonance imaging to capture hallucinatory experiences. Based on the participants' self-report of the psychosensory experiences that occurred during scanning, hallucinatory experiences were identified and divided into four stages: periods without hallucination ("OFF"), periods with hallucination ("ON"), transition periods between "OFF" and "ON", and the extinction of the hallucinatory experience ("END"). Using stochastic dynamic causal modeling analysis, this study first confirmed that the SAL played a critical and causal role in switching between the CEN and the DMN in schizophrenia. In addition, effective connectivity within the quadripartite model depended on the hallucinatory stage. In particular, "ON" periods were linked to memory-based sensory input from the hippocampus to the SAL, while "END" periods were associated with a takeover of the CEN in favor of a voluntary process. Finally, the pathophysiological and therapeutic implications of these findings are critically discussed. Hum Brain Mapp 37:2571-2586, 2016. © 2016 Wiley Periodicals, Inc.
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Encéfalo/fisiopatologia , Alucinações/fisiopatologia , Esquizofrenia/fisiopatologia , Adulto , Teorema de Bayes , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Feminino , Alucinações/diagnóstico por imagem , Humanos , Masculino , Modelos Neurológicos , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Escalas de Graduação Psiquiátrica , Descanso , Esquizofrenia/diagnóstico por imagem , AutorrelatoRESUMO
Cerebral microbleeds (CMBs) have emerged as a new imaging marker of small vessel disease. Composed of hemosiderin, CMBs are paramagnetic and can be detected with MRI sequences sensitive to magnetic susceptibility (typically, gradient recalled echo T2* weighted images). Nevertheless, their identification remains challenging on T2* magnitude images because of confounding structures and lesions. In this context, T2* phase image may play a key role in better characterizing CMBs because of its direct relationship with local magnetic field variations due to magnetic susceptibility difference. To address this issue, susceptibility-based imaging techniques were proposed, such as Susceptibility Weighted Imaging (SWI) and Quantitative Susceptibility Mapping (QSM). But these techniques have not yet been validated for 2D clinical data in multicenter settings. Here, we introduce 2DHF, a fast 2D phase processing technique embedding both unwrapping and harmonic filtering designed for data acquired in 2D, even with slice-to-slice inconsistencies. This method results in internal field maps which reveal local field details due to magnetic inhomogeneity within the region of interest only. This technique is based on the physical properties of the induced magnetic field and should yield consistent results. A synthetic phantom was created for numerical simulations. It simulates paramagnetic and diamagnetic lesions within a 'brain-like' tissue, within a background. The method was evaluated on both this synthetic phantom and multicenter 2D datasets acquired in standardized clinical setting, and compared with two state-of-the-art methods. It proved to yield consistent results on synthetic images and to be applicable and robust on patient data. As a proof-of-concept, we finally illustrate that it is possible to find a magnetic signature of CMBs and CMCs on internal field maps generated with 2DHF on 2D clinical datasets that give consistent results with CT-scans in a subsample of 10 subjects acquired with both modalities.
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Hemorragia Cerebral/patologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Algoritmos , Bases de Dados Factuais , HumanosRESUMO
Gilles de la Tourette syndrome is a neurodevelopmental disorder characterized by the presence of motor and vocal tics. We hypothesized that patients with this syndrome would present an aberrant pattern of cortical formation, which could potentially reflect global alterations of brain development. Using 3 Tesla structural neuroimaging, we compared sulcal depth, opening, and length and thickness of sulcal gray matter in 52 adult patients and 52 matched controls. Cortical sulci were automatically reconstructed and identified over the whole brain, using BrainVisa software. We focused on frontal, parietal, and temporal cortical regions, in which abnormal structure and functional activity were identified in previous neuroimaging studies. Partial correlation analysis with age, sex, and treatment as covariables of noninterest was performed amongst relevant clinical and neuroimaging variables in patients. Patients with Gilles de la Tourette syndrome showed lower depth and reduced thickness of gray matter in the pre- and post-central as well as superior, inferior, and internal frontal sulci. In patients with associated obsessive-compulsive disorder, additional structural changes were found in temporal, insular, and olfactory sulci. Crucially, severity of tics and of obsessive-compulsive disorder measured by Yale Global Tic severity scale and Yale-Brown Obsessive-Compulsive scale, respectively, correlated with structural sulcal changes in sensorimotor, temporal, dorsolateral prefrontal, and middle cingulate cortical areas. Patients with Gilles de la Tourette syndrome displayed an abnormal structural pattern of cortical sulci, which correlated with severity of clinical symptoms. Our results provide further evidence of abnormal brain development in GTS.
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Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Síndrome de Tourette/patologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Distribuição Normal , Índice de Gravidade de Doença , Adulto JovemRESUMO
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.
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Doença de Alzheimer/fisiopatologia , Encéfalo/irrigação sanguínea , Idade de Início , Encéfalo/fisiologia , Mapeamento Encefálico/métodos , Artérias Cerebrais/fisiopatologia , Estudos de Viabilidade , Feminino , Humanos , Angiografia por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Marcadores de SpinRESUMO
BACKGROUND: Growing body of evidence suggests that Parkinson's disease (PD) is associated with oxidative damage via iron accumulation in the substantia nigra (SN). Low ceruloplasmin (CP)-ferroxidase activity has been identified in the SN and the cerebrospinal fluid (CSF) of patients with PD. The iron chelator, deferiprone, reduces the abnormally high levels of iron in the SN. In order to determine CP's involvement in iron accumulation in SN and PD progression, we aim to compare the ability of iron chelation treatment to reducing both SN iron levels and motor handicap in PD patients according to the level of ceruloplasmin activity. METHODS: We used a moderate chelation protocol with deferiprone (DFP) based on a, 6-month delayed-start paradigm, randomized placebo controlled clinical trial in 40 PD patients. CP-ferroxidase activity was determined in blood and CSF together with the D544E gene polymorphism (rs701753). Iron levels were determined by R2* MRI sequence and the motor handicap by the UPDRS motor score. RESULTS: After 6 to 12 months of DFP treatment, greater reductions in SN iron levels and UPDRS motor scores were obtained in patients with higher serum and CSF levels of CP-ferroxidase activity. After 6 months of DFP treatment, the AT genotype group displayed greater reduction of iron level in the SN with greater CSF and serum levels of CP activity than the AA genotype group. CONCLUSION: Although most of the DFP-treated patients displayed clinical and radiological improvements, those with the lower CP activity appeared to respond better to iron chelation. Larger RCTs are now needed to establish whether pharmacological modulation of CP activity could be an innovative neuroprotective strategy in PD. TRIAL REGISTRATION: FAIR-PARK study (ClinicalTrials.gov reference: NCT00943748 ; French national reference number: 2008-006842-25). This study was approved by the French Drug Agency (ANSM) and the local institutional review board ("Comité de Protection des Personnes of Lille").
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Ceruloplasmina/metabolismo , Terapia por Quelação/métodos , Quelantes de Ferro/uso terapêutico , Ferro/metabolismo , Doença de Parkinson/tratamento farmacológico , Piridonas/uso terapêutico , Substância Negra/metabolismo , Idoso , Protocolos Clínicos , Deferiprona , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
Autosomal dominant cerebellar ataxia corresponds to a clinically and genetically heterogeneous group of neurodegenerative disorders that primarily affect the cerebellum. Here, we report the identification of the causative gene in spinocerebellar ataxia 21, an autosomal-dominant disorder previously mapped to chromosome 7p21.3-p15.1. This ataxia was firstly characterized in a large French family with slowly progressive cerebellar ataxia, accompanied by severe cognitive impairment and mental retardation in two young children. Following the recruitment of 12 additional young family members, linkage analysis enabled us to definitively map the disease locus to chromosome 1p36.33-p36.32. The causative mutation, (c.509C>T/p.P170L) in the transmembrane protein gene TMEM240, was identified by whole exome sequencing and then was confirmed by Sanger sequencing and co-segregation analyses. Index cases from 368 French families with autosomal-dominant cerebellar ataxia were also screened for mutations. In seven cases, we identified a range of missense mutations (c.509C>T/p.P170L, c.239C>T/p.T80M, c.346C>T/p.R116C, c.445G>A/p.E149K, c.511C>T/p.R171W), and a stop mutation (c.489C>G/p.Y163*) in the same gene. TMEM240 is a small, strongly conserved transmembrane protein of unknown function present in cerebellum and brain. Spinocerebellar ataxia 21 may be a particular early-onset disease associated with severe cognitive impairment.
Assuntos
Transtornos Cognitivos/genética , Deficiência Intelectual/genética , Proteínas de Membrana/genética , Mutação/fisiologia , Degenerações Espinocerebelares/genética , Adolescente , Idade de Início , Sequência de Aminoácidos , Criança , Pré-Escolar , Cromossomos Humanos Par 1/genética , Transtornos Cognitivos/psicologia , Estudos de Coortes , Sequência Conservada , Análise Mutacional de DNA , Exoma/genética , Feminino , França , Ligação Genética , Humanos , Lactente , Deficiência Intelectual/psicologia , Testes de Inteligência , Íntrons , Masculino , Proteínas de Membrana/fisiologia , Dados de Sequência Molecular , Testes Neuropsicológicos , Linhagem , Reação em Cadeia da Polimerase , Degenerações Espinocerebelares/patologia , Degenerações Espinocerebelares/psicologia , Adulto JovemRESUMO
INTRODUCTION: The purpose of this study was to study the effect of donepezil on the rate of hippocampal atrophy in prodromal Alzheimer's disease (AD). METHODS: A double-blind, randomized, placebo-controlled parallel group design using donepezil (10 mg/day) in subjects with suspected prodromal AD. Subjects underwent two brain magnetic resonance imaging scans (baseline and final visit). The primary efficacy outcome was the annualized percentage change (APC) of total hippocampal volume (left + right) measured by an automated segmentation method. RESULTS: Two-hundred and sixteen only subjects were randomized across 28 French expert clinical sites. In the per protocol population (placebo = 92 and donepezil = 82), the donepezil group exhibited a significant reduced rate of hippocampal atrophy (APC = -1.89%) compared with the placebo group (APC = -3.47%), P < .001. There was no significant difference in neuropsychological performance between treatment groups. DISCUSSION: A 45% reduction of rate of hippocampal atrophy was observed in prodromal AD following 1 year of treatment with donepezil compared with placebo.
Assuntos
Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Indanos/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Piperidinas/uso terapêutico , Idoso , Atrofia/tratamento farmacológico , Progressão da Doença , Donepezila , Método Duplo-Cego , Feminino , França , Humanos , Indanos/efeitos adversos , Imageamento por Ressonância Magnética , Masculino , Fármacos Neuroprotetores/efeitos adversos , Tamanho do Órgão , Piperidinas/efeitos adversos , Sintomas Prodrômicos , Resultado do TratamentoRESUMO
PURPOSE: To analyze white matter pathologic abnormalities by using diffusion-tensor (DT) imaging in a multicenter prospective cohort of comatose patients following cardiac arrest or traumatic brain injury (TBI). MATERIALS AND METHODS: Institutional review board approval and informed consent from proxies and control subjects were obtained. DT imaging was performed 5-57 days after insult in 49 cardiac arrest and 40 TBI patients. To control for DT imaging-processing variability, patients' values were normalized to those of 111 control subjects. Automated segmentation software calculated normalized axial diffusivity (λ1) and radial diffusivity (λâ¥) in 19 predefined white matter regions of interest (ROIs). DT imaging variables were compared by using general linear modeling, and side-to-side Pearson correlation coefficients were calculated. P values were corrected for multiple testing (Bonferroni). RESULTS: In central white matter, λ1 differed from that in control subjects in six of seven TBI ROIs and five of seven cardiac arrest ROIs (all P < .01). The λ⥠differed from that in control subjects in all ROIs in both patient groups (P < .01). In hemispheres, λ1 was decreased compared with that in control subjects in three of 12 TBI ROIs (P < .05) and nine of 12 cardiac arrest ROIs (P < .01). The λ⥠was increased in all TBI ROIs (P < .01) and in seven of 12 cardiac arrest ROIs (P < .05). Cerebral hemisphere λ1 was lower in cardiac arrest than in TBI in six of 12 ROIs (P < .01), while λ⥠was higher in TBI than in cardiac arrest in eight of 12 ROIs (P < .01). Diffusivity values were symmetrically distributed in cardiac arrest (P < .001 for side-to-side correlation) but not in TBI patients. CONCLUSION: DT imaging findings are consistent with the known predominance of cerebral hemisphere axonal injury in cardiac arrest and chiefly central myelin injury in TBI. This consistency supports the validity of DT imaging for differentiating axon and myelin damage in vivo in humans.