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1.
J Headache Pain ; 20(1): 93, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477012

RESUMO

BACKGROUND: Increasing evidence has suggested that the cerebellum is associated with pain and migraine. In addition, the descending pain system of the brainstem is the major site of trigeminal pain processing and modulation and has been discussed as a main player in the pathophysiology of migraine. Cerebellar and brainstem structural changes associated with migraineurs remain to be further investigated. METHODS: Voxel-based morphometry (VBM) (50 controls, 50 migraineurs without aura (MWoAs)) and diffusion tensor imaging (DTI) (46 controls, 46 MWoAs) were used to assess cerebellum and brainstem anatomical alterations associated with MWoAs. We utilized a spatially unbiased infratentorial template toolbox (SUIT) to perform cerebellum and brainstem optimized VBM and DTI analysis. We extracted the average diffusion values from a probabilistic cerebellar white matter atlas to investigate whether MWoAs exhibited microstructure alterations in the cerebellar peduncle tracts. RESULTS: MWoAs showed decreased fractional anisotropy (FA) in the vermis VI extending to the bilateral lobules V and VI of the cerebellum. We also found higher axial diffusivity (AD), mean diffusivity (MD), and radial diffusivity (RD) in the right inferior cerebellum peduncle tract in MWoAs. MWoAs exhibited both reduced gray matter volume and increased AD, MD and RD in the spinal trigeminal nucleus (SpV). CONCLUSION: MWoAs exhibited microstructural changes in the cerebellum and the local brainstem. These structural differences might contribute to dysfunction of the transmission and modulation of noxious information, trigeminal nociception, and conduction and integration of multimodal information in MWoAs. These findings further suggest involvement of the cerebellum and the brainstem in the pathology of migraine without aura.


Assuntos
Tronco Encefálico/patologia , Cerebelo/patologia , Enxaqueca sem Aura/patologia , Anisotropia , Tronco Encefálico/diagnóstico por imagem , Cerebelo/diagnóstico por imagem , Imagem de Tensor de Difusão , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Humanos , Masculino , Enxaqueca sem Aura/diagnóstico por imagem , Núcleo Espinal do Trigêmeo/diagnóstico por imagem , Núcleo Espinal do Trigêmeo/patologia , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
2.
Postgrad Med ; 131(7): 533-538, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31478419

RESUMO

Introduction: Depression in patients with mild cognitive impairment (MCI) and dementia of the Alzheimer's type (AD) is associated with worse prognosis. Indeed, depressed MCI patients have worse cognitive performance and greater loss of gray-matter volume in several brain areas. To date, knowledge of the factors that can mitigate this detrimental effect is still limited. The aim of the present study was to understand in what way cognitive reserve/brain reserve and depression interact and are linked to regional atrophy in early stage AD. Methods: Depression was evaluated with the Patient Health Questionnaire-9 in 90 patients with early AD, and a cutoff of ≥ 5 was used to separate depressed (n = 44) from non-depressed (n = 46) patients. Each group was further stratified into high/low cognitive reserve/brain reserve. Cognitive reserve was calculated using years of education as proxy, while normalized parenchymal volumes were used to estimate brain reserve. Voxel-based morphometry was carried out to extract and analyze gray-matter maps. 2 × 2 ANCOVAs were run to test the effect of the reserve-by-depression interaction on gray matter. Age and hippocampal ratio were used as covariates. Composite indices of major cognitive domains were also analyzed with comparable models. Results: No reserve-by-depression interaction was found in the analytical models of gray matter. Depression was associated with less gray matter volume in the cerebellum and parahippocampal gyrus. The brain reserve-by-depression interaction was a significant predictor of executive functioning. Among those with high brain reserve, depressed patients had poorer executive skills. No significant results were found in association with cognitive reserve. Conclusion: These findings suggest that brain reserve may modulate the association between neurodegeneration and depression in patients with MCI and dementia of the AD type, influencing in particular executive functioning.


Assuntos
Doença de Alzheimer/psicologia , Disfunção Cognitiva/psicologia , Reserva Cognitiva , Depressão/psicologia , Substância Cinzenta/diagnóstico por imagem , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/fisiopatologia , Atrofia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Cerebelo/diagnóstico por imagem , Cerebelo/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/fisiopatologia , Depressão/diagnóstico por imagem , Depressão/fisiopatologia , Feminino , Substância Cinzenta/patologia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Giro Para-Hipocampal/diagnóstico por imagem , Giro Para-Hipocampal/patologia , Questionário de Saúde do Paciente
3.
Postgrad Med ; 131(7): 509-522, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31422718

RESUMO

Objectives: Visual hallucinations (VH) are common in Lewy body disease (LBD), and have been associated with cognitive and structural brain alterations. Evidence so far concerns mainly Parkinson's disease (PD), but little is known about symptom-specific pathophysiological mechanisms across the LBD spectrum, especially related to the presence of dementia. The aim of the present pilot study was to investigate the neuroanatomical, and neuropsychological characteristics related to VH in two forms of LBD, namely dementia with Lewy bodies (DLB) and PD without dementia. Methods: Whole brain voxel-based morphometry (VBM) analyses on 3D MRI acquired structural brain scans, and neuropsychological testing were performed on 28 clinically diagnosed DLB (11 with VH, 17 NVH), and 24 PD (9 with VH, and 15 NVH) patients. In order to assess differences in gray matter (GM) regional volumes, and cognitive performance, hallucinating patients for each group were compared with corresponding non-hallucinating ones. Results: DLB patients with VH presented significantly worse visual attention deficits compared to those without, which persisted even when controlling for visual perception. Whole brain VBM analysis revealed decreased GM volume in DLB with VH in the right superior and medial frontal gyri, putamen, caudate nucleus and insula. Subcortical regional volumes were also significantly associated with visual attention performance. Hallucinating PD patients, instead, presented more severe executive dysfunction, but VBM showed no volumetric differences between the two PD subgroups. Post hoc region of interest analyses revealed striatal GM loss in PD with VH. Conclusion: Frontal and striatal GM atrophy may contribute to the emergence of VH in DLB, which may be fostered by the more severe attention deficits. Striatal GM loss and executive dysfunction, instead, appeared to underlie VH in PD without dementia.


Assuntos
Núcleo Caudado/diagnóstico por imagem , Lobo Frontal/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Alucinações/diagnóstico por imagem , Doença por Corpos de Lewy/diagnóstico por imagem , Doença de Parkinson/diagnóstico por imagem , Putamen/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Atenção , Estudos de Casos e Controles , Núcleo Caudado/patologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Feminino , Lobo Frontal/patologia , Substância Cinzenta/patologia , Alucinações/psicologia , Humanos , Doença por Corpos de Lewy/psicologia , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tamanho do Órgão , Doença de Parkinson/psicologia , Putamen/patologia , Percepção Visual
4.
BMC Neurosci ; 20(1): 39, 2019 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375091

RESUMO

BACKGROUND: Amblyopia is generally considered a neurodevelopmental disorder that results from abnormal visual experiences in early childhood and may persist to adulthood. The neural basis of amblyopia has been a matter of interest for many decades, but the critical neural processing sites in amblyopia are not entirely understood. Although many functional neuroimaging studies have found abnormal neuronal responses both within and beyond V1, few studies have focused on the neurophysiologic abnormalities in the visual cortex from the viewpoint of potential structural reorganization. In this study, we used a well-validated and highly accurate surface-based method to examine cortical morphologic changes in the visual cortex using multiple parameters (including cortical thickness, surface area, volume and mean curvature). RESULTS: The cortical thicknesses of the bilateral V1, left V2, left ventral V3, left V4 and left V5/MT+ in patients were significantly thinner than that in controls. The mean curvature of the bilateral V1 was significantly increased in the patients compared with the controls. For the surface area and gray matter volume, no significant differences were found between patients and controls in all region of interests. The cortical thicknesses of the bilateral V1 were both negatively correlated with the amount of anisometropia. No significant correlations were found between any other surface parameters and clinical variables. CONCLUSION: In addition to cortical thickness, the altered mean curvature of the cortex may indicate neuroanatomic impairments of the visual cortex in patients with anisometropic amblyopia. Moreover, the structural changes were bilateral in the primary visual cortex but were unilateral in the secondary and more senior visual cortex.


Assuntos
Ambliopia/patologia , Córtex Visual/patologia , Adulto , Atrofia/patologia , Estudos de Casos e Controles , Feminino , Substância Cinzenta/patologia , Humanos , Imagem por Ressonância Magnética , Masculino , Neuroimagem , Adulto Jovem
5.
Cancer Radiother ; 23(5): 370-377, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31331843

RESUMO

PUPOSE: Medulloblastoma is the most common primary malignant central nervous system tumor in childhood, accounting for 16-25% of cases (1). New treatment approaches have led to improved survival rates; however toxicities are still a major concern. PATIENTS AND METHODS: Participants were selected from the records of patients who were treated with craniospinal irradiation for medulloblastoma. Between January 2008 and December 2012, 62 patients were diagnosed with medulloblastoma at the national institute of oncology Rabat, 27 patients were still alive at the time of the study, of which n=16 patients were included in the study. The mean age of patients at the time of the study was 9.6 years. All children were treated with radiation therapy and chemotherapy, according to standard protocols. Median follow-up between treatment and evaluation was 4 years. All the children were assessed with the Wechsler Intelligence Scale for Children - fourth Edition (WISC-IV) three to five years after completion of radiotherapy. The test was administered by two well-trained psychologists in a distraction-free environment. The scoring was then reviewed by a psychologist from Brooklyn College. RESULTS: The mean standard score Full-Scale Intelligence Quotient (FSIQ) (M=63, SD=12.6) was found to be in the extremely low range and in the 1st percentile rank (PR), compared to the general population. All the measured primary index scales were below typical performance: verbal comprehension (M=67.7, SD=13.1), perceptual reasoning (M=63.5, SD=13.8) and processing speed (M=62.7, SD=15.5) were all found to be in the extremely low range, while xorking memory (M=75.5, SD=10.8) was found to be in the borderline range compared to the general population. To identify factors influencing the results, we performed both univariate and multivariate analyses. Age at the time of radiotherapy, initial clinical stage, total cranial radiotherapy dose, socioeconomic status, and the time of evaluation were identified as significantly impacting cognitive scores in the univariate analysis. In the multivariate analysis, only age at the time of radiotherapy and initial clinical stage remained factors significantly impacting cognitive outcomes with P=0.001 and P<0.001 respectively. CONCLUSION: Our study is evidence that tremendous efforts are still to be made in low-income countries to correctly measure neurocognitive dysfunction in medulloblastoma survivors and to prepare those patients to a typical life after the completion of treatment.


Assuntos
Neoplasias Cerebelares/radioterapia , Irradiação Craniana/efeitos adversos , Meduloblastoma/radioterapia , Transtornos Neurocognitivos/etiologia , Fatores Etários , Antineoplásicos/uso terapêutico , Neoplasias Cerebelares/tratamento farmacológico , Criança , Pré-Escolar , Terapia Combinada , Seguimentos , Substância Cinzenta/lesões , Substância Cinzenta/patologia , Hipocampo/lesões , Hipocampo/patologia , Humanos , Meduloblastoma/tratamento farmacológico , Transtornos da Memória/etiologia , Transtornos da Memória/patologia , Transtornos Neurocognitivos/patologia , Tamanho do Órgão , Modelos de Riscos Proporcionais , Escalas de Wechsler , Substância Branca/lesões , Substância Branca/patologia
6.
Neurology ; 93(4): e334-e346, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31266904

RESUMO

OBJECTIVE: To investigate the relationship between cognitive reserve (CR) and clinical progression across the Alzheimer disease (AD) spectrum. METHODS: We selected 839 ß-amyloid (Aß)-positive participants with normal cognition (NC, n = 175), mild cognitive impairment (MCI, n = 437), or AD dementia (n = 227) from the Alzheimer's Disease Neuroimaging Initiative (ADNI). CR was quantified using standardized residuals (W scores) from a (covariate-adjusted) linear regression with global cognition (13-item Alzheimer's Disease Assessment Scale-cognitive subscale) as an independent variable of interest, and either gray matter volumes or white matter hyperintensity volume as dependent variables. These W scores, reflecting whether an individual's degree of cerebral damage is lower or higher than clinically expected, were tested as predictors of diagnostic conversion (i.e., NC to MCI/AD dementia, or MCI to AD dementia) and longitudinal changes in memory (ADNI-MEM) and executive functions (ADNI-EF). RESULTS: The median follow-up period was 24 months (interquartile range 6-42). Corrected for age, sex, APOE4 status, and baseline cerebral damage, higher gray matter volume-based W scores (i.e., greater CR) were associated with a lower diagnostic conversion risk (hazard ratio [HR] 0.22, p < 0.001) and slower decline in memory (ß = 0.48, p < 0.001) and executive function (ß = 0.67, p < 0.001). Stratified by disease stage, we found similar results for NC (diagnostic conversion: HR 0.30, p = 0.038; ADNI-MEM: ß = 0.52, p = 0.028; ADNI-EF: ß = 0.42, p = 0.077) and MCI (diagnostic conversion: HR 0.21, p < 0.001; ADNI-MEM: ß = 0.43, p = 0.003; ADNI-EF: ß = 0.59, p < 0.001), but opposite findings (i.e., more rapid decline) for AD dementia (ADNI-MEM: ß = -0.91, p = 0.002; ADNI-EF: ß = -0.77, p = 0.081). CONCLUSIONS: Among Aß-positive individuals, greater CR related to attenuated clinical progression in predementia stages of AD, but accelerated cognitive decline after the onset of dementia.


Assuntos
Doença de Alzheimer/psicologia , Disfunção Cognitiva/psicologia , Reserva Cognitiva , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/diagnóstico por imagem , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Compostos de Anilina , Estudos de Casos e Controles , Disfunção Cognitiva/líquido cefalorraquidiano , Disfunção Cognitiva/diagnóstico por imagem , Meios de Contraste , Progressão da Doença , Etilenoglicóis , Função Executiva , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Humanos , Masculino , Memória , Pessoa de Meia-Idade , Tamanho do Órgão , Fragmentos de Peptídeos/líquido cefalorraquidiano , Tiazóis , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
7.
PLoS One ; 14(5): e0217922, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31150514

RESUMO

To meet the need for Parkinson's disease biomarkers and evidence for amount and distribution of pathological changes, MRI diffusion tensor imaging (DTI) has been explored in a number of previous studies. However, conflicting results warrant further investigations. As tissue microstructure, particularly of the grey matter, is heterogeneous, a more precise diffusion model may benefit tissue characterization. The purpose of this study was to analyze the diffusion-based imaging technique restriction spectrum imaging (RSI) and DTI, and their ability to detect microstructural changes within brain regions associated with motor function in Parkinson's disease. Diffusion weighted (DW) MR images of a total of 100 individuals, (46 Parkinson's disease patients and 54 healthy controls) were collected using b-values of 0-4000s/mm2. Output diffusion-based maps were estimated based on the RSI-model combining the full set of DW-images (Cellular Index (CI), Neurite Density (ND)) and DTI-model combining b = 0 and b = 1000 s/mm2 (fractional anisotropy (FA), Axial-, Mean- and Radial diffusivity (AD, MD, RD)). All parametric maps were analyzed in a voxel-wise group analysis, with focus on typical brain regions associated with Parkinson's disease pathology. CI, ND and DTI diffusivity metrics (AD, MD, RD) demonstrated the ability to differentiate between groups, with strongest performance within the thalamus, prone to pathology in Parkinson's disease. Our results indicate that RSI may improve the predictive power of diffusion-based MRI, and provide additional information when combined with the standard diffusivity measurements. In the absence of major atrophy, diffusion techniques may reveal microstructural pathology. Our results suggest that protocols for MRI diffusion imaging may be adapted to more sensitive detection of pathology at different sites of the central nervous system.


Assuntos
Diagnóstico por Imagem , Imagem de Tensor de Difusão , Degeneração Neural/diagnóstico , Doença de Parkinson/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Tronco Encefálico/diagnóstico por imagem , Tronco Encefálico/patologia , Imagem de Difusão por Ressonância Magnética , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Degeneração Neural/diagnóstico por imagem , Degeneração Neural/patologia , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/patologia , Substância Negra/diagnóstico por imagem , Substância Negra/patologia , Tálamo/diagnóstico por imagem , Tálamo/patologia
8.
Mult Scler Relat Disord ; 33: 107-115, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31181540

RESUMO

BACKGROUND: Relapsing-Remitting MS (RRMS) Deep Grey Matter (DGM) 5 year changes were examined using MRI measures of volume, transverse relaxation rate (R2*) and quantitative magnetic susceptibility (QS). By applying Discriminative Analysis of Regional Evolution (DARE), R2* and QS changes from iron and non-iron sources were separated. METHODS: 25 RRMS and 25 age-matched control subjects were studied at baseline and 5-year follow-up. Bulk DGM mean R2* and QS of the caudate nucleus, putamen, thalamus and globus pallidus were analyzed using mixed factorial analysis (α = 0.05) with sex as a covariate, while DARE employed non-parametric analysis to study regional changes. Regression/correlation analysis was performed with disease duration and MS Severity Score (MSSS). RESULTS: No significant change in Extended Disability Status Score was found over 5 years (baseline = 2.4 ±â€¯1.2; follow-up = 2.8 ±â€¯1.3). Significant time effects were found for R2* in the caudate (Q = 0.000008; η2 = 0.36), putamen (Q = 0.0000007; η2 = 0.43), and globus pallidus (Q = 0.0000007; η2 = 0.43), while significant longitudinal effects were only found for QS in the putamen (Q = 0.002; η2 = 0.22). Significant bulk interaction was only found for thalamus volume (Q = 0.02; η2 = 0.20). Iron decrease was the only detected significant effect using DARE, and the highest significant DARE effect size was mean thalamus R2* iron decrease (Q = 0.002; η2 = 0.26). No significant correlations or regressions were demonstrated with clinical measures. CONCLUSIONS: Thalamic atrophy was the only bulk effect that demonstrated different rates of changes over 5 years compared to age-matched controls. DARE Iron decrease in regions of the caudate, putamen, and thalamus were prominent features in stable RRMS over 5 years.


Assuntos
Encéfalo/patologia , Substância Cinzenta/patologia , Ferro/análise , Esclerose Múltipla Recidivante-Remitente/patologia , Adulto , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Estudos Longitudinais , Imagem por Ressonância Magnética , Masculino
9.
Brain Struct Funct ; 224(6): 2087-2101, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31161472

RESUMO

Despite the common co-occurrence of cognitive impairment and brain structural deficits in alcoholism, demonstration of relations between regional gray matter volumes and cognitive and motor processes have been relatively elusive. In pursuit of identifying brain structural substrates of impairment in alcoholism, we assessed executive functions (EF), episodic memory (MEM), and static postural balance (BAL) and measured regional brain gray matter volumes of cortical, subcortical, and cerebellar structures commonly affected in individuals with alcohol dependence (ALC) compared with healthy controls (CTRL). ALC scored lower than CTRL on all composite scores (EF, MEM, and BAL) and had smaller frontal, cingulate, insular, parietal, and hippocampal volumes. Within the ALC group, poorer EF scores correlated with smaller frontal and temporal volumes; MEM scores correlated with frontal volume; and BAL scores correlated with frontal, caudate, and pontine volumes. Exploratory analyses investigating relations between subregional frontal volumes and composite scores in ALC yielded different patterns of associations, suggesting that different neural substrates underlie these functional deficits. Of note, orbitofrontal volume was a significant predictor of memory scores, accounting for almost 15% of the variance; however, this relation was evident only in ALC with a history of a non-alcohol substance diagnosis and not in ALC without a non-alcohol substance diagnosis. The brain-behavior relations observed provide evidence that the cognitive and motor deficits in alcoholism are likely a result of different neural systems and support the hypothesis that a number of identifiable neural systems rather than a common or diffuse neural pathway underlies cognitive and motor deficits observed in chronic alcoholism.


Assuntos
Alcoolismo , Cognição/fisiologia , Substância Cinzenta/patologia , Córtex Motor/patologia , Vias Neurais/patologia , Adulto , Idoso , Alcoolismo/patologia , Alcoolismo/fisiopatologia , Cerebelo/patologia , Cerebelo/fisiopatologia , Função Executiva/fisiologia , Feminino , Substância Cinzenta/fisiopatologia , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Memória Episódica , Pessoa de Meia-Idade , Córtex Motor/fisiopatologia , Vias Neurais/fisiopatologia
10.
Pain Physician ; 22(3): E191-E203, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31151342

RESUMO

BACKGROUND: Although the association of gray matter morphology alterations and pain-related psychosocial characteristics with pain intensity and chronification in people with chronic spinal pain is evident, research on their mutual interaction is scarce and does not account for possible gender differences. Gender-based differences are, however, of utmost importance to consider when examining pain neurobiology. OBJECTIVES: To look for gender differences in the association between magnetic resonance imaging- (MRI) derived brain gray matter morphology and self-reported psychosocial characteristics. STUDY DESIGN: An explorative, observational study. SETTING: University Hospitals Ghent and Brussels, Belgium. METHODS: Brain gray matter morphology (using MRI) and self-reported psychosocial characteristics were examined in women and men with nonspecific chronic spinal pain. Statistical analyses were performed in SPSS and R to identify differences between men and women regarding brain gray matter, self-reported psychosocial characteristics, as well as gender differences in the association between those outcome measures. RESULTS: A total of 94 people with chronic spinal pain were studied, including 32 men (15 suffering from neck pain, 17 suffering from low back pain; demographics [mean ± SD] age: 45.00 ± 12.02 years; pain duration: 128.37 ± 110.45 months), and 62 women (36 suffering from neck pain, 26 suffering from low back pain; demographics [mean ± SD] age: 38.78 ± 12.69 years; pain duration: 114.27 ± 92.45 months). Woman showed larger (positive) associations of several central brain areas (paracentral, precentral, postcentral, etc.) with perceived consequences (P < 0.001), emotional representations (P < 0.001), chronicity (P < 0.001), and pain catastrophizing (P< 0.001). Men showed larger (both positive and negative) associations of the precuneus cortex, the precentral gyrus, and the insula with perceived personal control (P < 0.001) and kinesiophobia (P < 0.001). LIMITATIONS: Other factors, such as menstrual cycle and medication can have a certain influence, and were only partly taken into consideration in the present investigation to obtain sufficient power. Another limitation is the observational study design, which hampers the possibility to look for causal or temporal interactions. CONCLUSIONS: Gray matter morphology relates differently to psychosocial characteristics in women and men. These explorative findings provide ideas for further research to investigate if targeting perceived negative consequences of the illness, perceived emotional representations, perceived chronicity, and pain catastrophizing in women, and perceived personal control of the illness and kinesiophobia in men, could contribute to the normalization of brain alterations in people with nonspecific chronic spinal pain. KEY WORDS: Gray matter, brain morphology, central nervous system, illness perceptions, central sensitization.


Assuntos
Encéfalo/patologia , Dor Crônica/patologia , Dor Crônica/psicologia , Substância Cinzenta/patologia , Caracteres Sexuais , Adulto , Sensibilização do Sistema Nervoso Central/fisiologia , Dor Crônica/etiologia , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Nucl Med Commun ; 40(9): 905-912, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31246935

RESUMO

OBJECTIVE: The purpose of this study was to investigate whether ß-amyloid (Aß) deposition was associated with local atrophy of corresponding areas in the brain. METHODS: [11C]2-[2-(2-Dimethylaminothiazol-5-yl) ethenyl-6-[2-(fluoro)ethoxy]benzoxazole (BF-227)-PET, MRI and neuropsychological tests were carried out on 56 subjects, out of which 21 were patients with Alzheimer's disease (AD), 20 were patients with mild cognitive impairment (MCI) and 15 were normal controls (NC). The BF-227 uptake in each local brain region was set up with automated anatomical labeling atlas using Wake Forest University PickAtlas software and local standardized uptake value ratios of BF-227 were calculated as the average value of right and left using the MRIcron software. RESULTS: Group comparisons of Aß deposition as determined by BF-227 uptake using PET imaging showed no significant differences between MCI and AD. Aß deposition was significantly higher in MCI and AD than in NC. The correlation analysis between local Aß deposition and gray matter atrophy showed that in AD, the Aß deposition in the inferior temporal gyrus was strongly related to the gray matter atrophy in this region. On the contrary, the Aß deposition in the precuneus was associated with the atrophy in the right occipital-temporal region. In the NC, the Aß deposition in the inferior temporal gyrus was associated with the atrophy in the precuneus. CONCLUSION: In the AD, the relationship between the Aß deposition and local atrophy is area-dependent. In NC, Aß deposition in the inferior temporal gyrus correlated to the atrophy in the precuneus.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Benzoxazóis , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Imagem por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Tiazóis , Idoso , Atrofia/diagnóstico por imagem , Atrofia/metabolismo , Benzoxazóis/metabolismo , Transporte Biológico , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Humanos , Masculino , Tamanho do Órgão , Tiazóis/metabolismo
12.
Nat Neurosci ; 22(8): 1269-1275, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31235933

RESUMO

Inhibitory extracellular matrices form around mature neurons as perineuronal nets containing chondroitin sulfate proteoglycans that limit axonal sprouting after CNS injury. The enzyme chondroitinase (Chase) degrades inhibitory chondroitin sulfate proteoglycans and improves axonal sprouting and functional recovery after spinal cord injury in rodents. We evaluated the effects of Chase in rhesus monkeys that had undergone C7 spinal cord hemisection. Four weeks after hemisection, we administered multiple intraparenchymal Chase injections below the lesion, targeting spinal cord circuits that control hand function. Hand function improved significantly in Chase-treated monkeys relative to vehicle-injected controls. Moreover, Chase significantly increased corticospinal axon growth and the number of synapses formed by corticospinal terminals in gray matter caudal to the lesion. No detrimental effects were detected. This approach appears to merit clinical translation in spinal cord injury.


Assuntos
Condroitinases e Condroitim Liases/uso terapêutico , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Axônios/patologia , Condroitinases e Condroitim Liases/administração & dosagem , Condroitinases e Condroitim Liases/efeitos adversos , Substância Cinzenta/patologia , Mãos/inervação , Mãos/fisiopatologia , Injeções Intralesionais , Macaca mulatta , Masculino , Microglia/patologia , Neurônios Motores/patologia , Desempenho Psicomotor , Tratos Piramidais/patologia , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/fisiopatologia , Suínos , Sinapses/patologia , Resultado do Tratamento
13.
Australas Phys Eng Sci Med ; 42(2): 563-571, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31054027

RESUMO

The inconsistency of volumetric results often seen in MR neuroimaging studies can be partially attributed to small sample sizes and variable data analysis approaches. Increased sample size through multi-scanner studies can tackle the former, but combining data across different scanner platforms and field-strengths may introduce a variability factor capable of masking subtle statistical differences. To investigate the sample size effect on regression analysis between depressive symptoms and grey matter volume (GMV) loss in Alzheimer's disease (AD), a retrospective multi-scanner investigation was conducted. A cohort of 172 AD patients, with or without comorbid depressive symptoms, was studied. Patients were scanned with different imaging protocols in four different MRI scanners operating at either 1.5 T or 3.0 T. Acquired data were uniformly analyzed using the computational anatomy toolbox (CAT12) of the statistical parametric mapping (SPM12) software. Single- and multi-scanner regression analyses were applied to identify the anatomical pattern of correlation between GM loss and depression severity. A common anatomical pattern of correlation between GMV loss and increased depression severity, mostly involving sensorimotor areas, was identified in all patient subgroups imaged in different scanners. Analysis of the pooled multi-scanner data confirmed the above finding employing a more conservative statistical criterion. In the retrospective multi-scanner setting, a significant correlation was also exhibited for temporal and frontal areas. Increasing the sample size by retrospectively pooling multi-scanner data, irrespective of the acquisition platform and parameters employed, can facilitate the identification of anatomical areas with a strong correlation between GMV changes and depression symptoms in AD patients.


Assuntos
Doença de Alzheimer/complicações , Doença de Alzheimer/diagnóstico por imagem , Depressão/complicações , Imagem por Ressonância Magnética , Neuroimagem , Idoso , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Humanos , Masculino , Tamanho do Órgão , Análise de Regressão , Tamanho da Amostra
14.
Brain Lang ; 194: 58-64, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31102976

RESUMO

Although dysarthria is a common pattern in multiple sclerosis (MS), the contribution of specific brain areas to key factors of dysarthria remains unknown. Speech data were acquired from 123 MS patients with Expanded Disability Status Scale (EDSS) ranging from 1 to 6.5 and 60 matched healthy controls. Results of computerized acoustic analyses of subtests on spastic and ataxic aspects of dysarthria were correlated with MRI-based brain volume measurements. Slow articulation rate during reading was associated with bilateral white and grey matter loss whereas reduced maximum speed during oral diadochokinesis was related to greater cerebellar involvement. Articulation rate showed similar correlation to whole brain atrophy (r = 0.46, p < 0.001) as the standard clinical scales such as EDSS (r = -0.45, p < 0.001). Our results support the critical role of the pyramidal tract and cerebellum in the modification of motor speech timing in MS.


Assuntos
Encéfalo/diagnóstico por imagem , Disartria/diagnóstico por imagem , Esclerose Múltipla/diagnóstico por imagem , Adulto , Atrofia/diagnóstico por imagem , Encéfalo/patologia , Disartria/etiologia , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Leitura
15.
BMC Med Imaging ; 19(1): 42, 2019 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-31126254

RESUMO

BACKGROUND: Brain image segmentation is the basis and key to brain disease diagnosis, treatment planning and tissue 3D reconstruction. The accuracy of segmentation directly affects the therapeutic effect. Manual segmentation of these images is time-consuming and subjective. Therefore, it is important to research semi-automatic and automatic image segmentation methods. In this paper, we propose a semi-automatic image segmentation method combined with a multi-atlas registration method and an active contour model (ACM). METHOD: We propose a multi-atlas active contour segmentation method using a template optimization algorithm. First, a multi-atlas registration method is used to obtain the prior shape information of the target tissue, and then a label fusion algorithm is used to generate the initial template. Second, a template optimization algorithm is used to reduce the multi-atlas registration errors and generate the initial active contour (IAC). Finally, a ACM is used to segment the target tissue. RESULTS: The proposed method was applied to the challenging publicly available MR datasets IBSR and MRBrainS13. In the MRBrainS13 datasets, we obtained an average thalamus Dice similarity coefficient of 0.927 ± 0.014 and an average Hausdorff distance (HD) of 2.92 ± 0.53. In the IBSR datasets, we obtained a white matter (WM) average Dice similarity coefficient of 0.827 ± 0.04 and a gray gray matter (GM) average Dice similarity coefficient of 0.853 ± 0.03. CONCLUSION: In this paper, we propose a semi-automatic brain image segmentation method. The main contributions of this paper are as follows: 1) Our method uses a multi-atlas registration method based on affine transformation, which effectively reduces the multi-atlas registration time compared to the complex nonlinear registration method. The average registration time of each target image in the IBSR datasets is 255 s, and the average registration time of each target image in the MRBrainS13 datasets is 409 s. 2) We used a template optimization algorithm to improve registration error and generate a continuous IAC. 3) Finally, we used a ACM to segment the target tissue and obtain a smooth continuous target contour.


Assuntos
Encefalopatias/diagnóstico por imagem , Intensificação de Imagem Radiográfica/métodos , Algoritmos , Atlas como Assunto , Encefalopatias/patologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Humanos , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
16.
Neurology ; 92(17): e1939-e1947, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-30971481

RESUMO

OBJECTIVE: To assess brain morphometry in a sample of patients with juvenile-onset Huntington disease (JOHD) and several mouse models of Huntington disease (HD) that likely represent the human JOHD phenotype. METHODS: Despite sharing the mutation in the Huntingtin gene, adult-onset HD characteristically presents as a hyperkinetic motor disorder, while JOHD typically presents as a hypokinetic motor disease. The University of Iowa Kids-JHD program enrolls individuals 5 to 25 years of age who have already received the clinical diagnosis. A total of 19 children with juvenile HD (JHD) (mean CAG = 72) were studied. Patients with JHD were compared to healthy controls (n = 234) using a cross-sectional study design. Volumetric data from structural MRI was compared between groups. In addition, we used the same procedure to evaluate brain morphology of R6/2, zQ175, HdhQ250 HD mice models. RESULTS: Participants with JHD had substantially reduced intracranial volumes. After controlling for the small intracranial volume size, the volumes of subcortical regions (caudate, putamen, globus pallidus, and thalamus) and of cortical white matter were significantly decreased in patients with JHD. However, the cerebellum was proportionately enlarged in the JHD sample. The cerebral cortex was largely unaffected. Likewise, HD mice had a lower volume of striatum and a higher volume of cerebellum, mirroring the human MRI results. CONCLUSIONS: The primary pathology of JOHD extends beyond changes in the striatal volume. Brain morphology in both mice and human patients with JHD shows proportional cerebellar enlargement. This pattern of brain changes may explain the unique picture of hypokinetic motor symptoms in JHD, which is not seen in the hyperkinetic chorea-like phenotype of adult-onset HD.


Assuntos
Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Doença de Huntington/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adolescente , Adulto , Animais , Encéfalo/patologia , Criança , Pré-Escolar , Modelos Animais de Doenças , Feminino , Substância Cinzenta/patologia , Humanos , Doença de Huntington/patologia , Imagem por Ressonância Magnética , Masculino , Camundongos , Tamanho do Órgão/fisiologia , Substância Branca/patologia , Adulto Jovem
17.
Neuroradiology ; 61(6): 695-702, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30949745

RESUMO

PURPOSE: Previous studies have focused on global cerebral alterations observed in cirrhosis. However, little was known about the specific abnormalities of vision-related brain regions in cirrhotic patients. In this study, we sought to explore neurological alterations of vision-related regions by measuring brain resting-state network connectivity, based on the structural investigation in cirrhotic patients without clinical sign of hepatic encephalopathy (HE). METHODS: Structural and functional magnetic resonance image (MRI) data were collected from 20 hepatitis B virus (HBV)-related cirrhotic patients without clinical sign of HE and from 20 healthy controls (HC). Voxel-based morphometric (VBM) analysis and brain functional network analysis were performed to detect abnormalities in cerebral structure and function. RESULTS: Cirrhotic patients showed regions with the most significant gray matter reduction primarily in vision-related brain regions, including the bilateral lingual gyri, left putamen, right fusiform gyrus, and right calcarine gyrus, and other significant gray matter reductions were distributed in bilateral hippocampus. Based on structural investigation focused on vision-related regions, brain functional network analysis revealed decreased functional connectivity between brain functional networks within vision-related regions (primary visual network (PVN), higher visual network (HVN), visuospatial network (VSN)) in the patient group compared with HC group. CONCLUSION: These results indicate that structural and functional impairment were evident in the vision-related brain regions in cirrhotic patients without clinical sign of hepatic encephalopathy. The physiopathology and clinical relevance of these changes could not be ascertained from the present study, which provided a basis for further evolution of the disease.


Assuntos
Substância Cinzenta/diagnóstico por imagem , Encefalopatia Hepática/diagnóstico , Imagem por Ressonância Magnética/métodos , Córtex Visual/diagnóstico por imagem , Estudos de Casos e Controles , Feminino , Substância Cinzenta/patologia , Encefalopatia Hepática/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Visual/patologia
18.
Mult Scler Relat Disord ; 31: 74-81, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30951968

RESUMO

PURPOSE: To investigate gray-matter (GM) lesions in relapsing-remitting multiple sclerosis (MS) using double-inversion recovery (DIR) MRI, determine GM lesions prevalence, spatial distribution and characterize their contrast-enhancement, diffusion characteristics and compare them to white-matter (WM) lesions. This is the first study, to our knowledge, to investigate GM MS lesions using double-inversion recovery MRI, to determine GM lesion prevalence and location, and characterize contrast-enhancement and diffusion characteristics, compared to WM lesion characteristics in the same patients. We also correlated GM lesion counts, volume and apparent diffusion coefficient (ADC) with total brain, WM, and GM volumes, as well as 25-foot walk test as a clinical disability. MATERIALS AND METHODS: This retrospective study included 44 relapsing-remitting MS patients (12M/32F, 41 ± 13 years) and 24 age-matched healthy controls (14M/10F, 36 ± 13 years). Lesions were segmented based on DIR and grouped into GM, subcortical WM, and periventricular WM lesions. ADC was tabulated for contrast-enhancing and non-enhancing lesions. Unpaired two sample t-tests were used for comparison between groups. Linear regression was used to evaluate the relationship between number of GM lesions, number of total lesions, total GM lesion volume, and total WM lesion volume with brain volumes and clinical data. RESULTS: GM MS lesions were present in the majority (86.4%, 38/44) of RRMS patients based on DIR, suggesting GM damage plays an important role in MS pathogenesis. The majority of the GM lesions were located in the frontal lobe. The percentage of lesions in GM that were contrast-enhanced was similar to those in WM, suggesting that blood-brain barrier integrity is likely affected similarly in GM and WM. Contrast-enhanced GM lesions showed higher ADC. GM lesion count and volume were correlated with global and regional brain atrophy, and with more severe disability group. CONCLUSION: This study characterized GM MS lesions using double-inversion recovery, contrast-enhanced and diffusion MRI. Understanding GM lesion pathophysiology using MRI in vivo, may prove useful for improving targeted therapy and monitoring disease progression.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/patologia , Adulto , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Aumento da Imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
19.
J Med Syst ; 43(5): 131, 2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30937597

RESUMO

In order to study the application of multi-modal magnetic resonance imaging (MRI) fusion technology in schizophrenia, a 4-way multi-modal fusion method based on mCCA+jICA is used to fuse the local consistency and functional network connection of resting-state functional MRI, gray matter volume of structural MRI, and partial anisotropy of diffusion MRI four characteristics of large sample of schizophrenic patients in multi-site China, trying to find out the common characteristics of function and structure of significant differences between schizophrenia and healthy controls. It is found that compared with normal people, schizophrenic patients show higher local consistency, lower gray matter volume, lower functional network connectivity and decreased white matter integrity in the anterior thalamic radiation, upper bundle and other bundles in brain areas such as basal ganglia network, hippocampus and prominence network. There is a significant correlation between a thalamocortical perceptual loop and auditory hallucination in schizophrenia, and there is a high degree of spatial consistency and commonality among the three MRI features. The higher the volume of gray matter in the dorsolateral and medial prefrontal cortex is, the higher the integrity of white matter fibers such as corticospinal tract, superior longitudinal tract and anterior thalamic radiation is, the higher the digital backward score is, and the better the working memory ability of the subjects is.


Assuntos
Encéfalo/patologia , Processamento de Imagem Assistida por Computador/métodos , Imagem por Ressonância Magnética/métodos , Esquizofrenia/patologia , Adolescente , Adulto , Anisotropia , Encéfalo/diagnóstico por imagem , China , Imagem de Difusão por Ressonância Magnética , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Alucinações , Humanos , Masculino , Pessoa de Meia-Idade , Esquizofrenia/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Adulto Jovem
20.
Neuroradiology ; 61(6): 703-710, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31011773

RESUMO

PURPOSE: Altered brain volume and metabolic variables have been found in subjects with obesity. However, the role of metabolic parameters in gray matter volume (GMV) has been poorly investigated. This study aimed to investigate the relationship between the metabolic parameters and brain volume in subjects with obesity. METHODS: Thirty-seven subjects with obesity and 39 age and sex matched normal-weight controls were included in this study. Eighteen of the 37 participants who underwent sleeve gastrectomy were included in the longitudinal analysis. Blood samples and high-resolution 3T T1-weighted magnetic resonance images were collected. Metabolic parameters in plasma and GMV were measured. RESULTS: Multiple linear regression analysis showed that gray matter reduction in several cognition-related cortices including right angular gyrus, superior occipital cortex, superior parietal cortex, and cerebellum was related to decreased creatinine, as well as increased triglyceride, HbA1c, and low-density lipoprotein in plasma in subjects with obesity. Weight loss after the surgery induced significant recovery of altered metabolic parameters and decreased gray matter volume. Furthermore, changes in the four metabolic parameters before and after the surgery were associated with changes in gray matter volume. CONCLUSION: Our results suggest that the gray matter reduction is related to decreased creatinine as well as increased triglyceride, HbA1c, and low-density lipoprotein in plasma in subjects with obesity.


Assuntos
Creatinina/sangue , Hemoglobina A Glicada/metabolismo , Substância Cinzenta/patologia , Lipoproteínas LDL/sangue , Imagem por Ressonância Magnética/métodos , Obesidade/sangue , Obesidade/complicações , Triglicerídeos/sangue , Adolescente , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Estudos Longitudinais , Masculino , Tamanho do Órgão
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