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INTRODUCTION: The increasing use of large sample sizes for population and personalized medicine requires high-throughput tools for imaging processing that can handle large amounts of data with diverse image modalities, perform a biologically meaningful information reduction, and result in comprehensive quantification. Exploring the reproducibility of these tools reveals the specific strengths and weaknesses that heavily influence the interpretation of results, contributing to transparence in science. METHODS: We tested-retested the reproducibility of MRICloud, a free automated method for whole-brain, multimodal MRI segmentation and quantification, on two public, independent datasets of healthy adults. RESULTS: The reproducibility was extremely high for T1-volumetric analysis, high for diffusion tensor images (DTI) (however, regionally variable), and low for resting-state fMRI. CONCLUSION: In general, the reproducibility of the different modalities was slightly superior to that of widely used software. This analysis serves as a normative reference for planning samples and for the interpretation of structure-based MRI studies.
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Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Neuroimagem Funcional/métodos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Algoritmos , Conectoma , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Software , Adulto JovemRESUMO
INTRODUCTION: Friedreich's ataxia (FRDA) is the most common autosomal-recessive ataxia worldwide. It is characterized by early onset, sensory abnormalities, and slowly progressive ataxia. However, some individuals manifest the disease after the age of 25 years and are classified as late-onset FRDA (LOFA). Therefore, we propose a transversal multimodal MRI-based study to investigate which anatomical substrates are involved in classical (cFRDA) and LOFA. METHODS: We enrolled 36 patients (13 with LOFA) and 29 healthy controls. All subjects underwent magnetic resonance imaging in a 3 T device; three-dimensional high-resolution T1-weighted images and diffusion tensor images were used to assess gray and white matter, respectively. We used T1 multiatlas approach to assess deep gray matter and cortical thickness measures to evaluate cerebral cortex and DTI multiatlas approach to assess white matter. All analyses were corrected for multiple comparisons. RESULTS: Group comparison showed that both groups presented gray matter atrophy mostly in the motor cortex. Regarding white matter, we found abnormalities in the cerebellar peduncles, pyramidal tracts, midbrain, pons, and medulla oblongata for both groups, but the microstructural abnormalities in the cFRDA group were more widespread. In addition, we found that the corticospinal tract presented more severe microstructural damage in the LOFA group. Finally, the midbrain volume of the cFRDA, but not of the LOFA group, correlated with disease duration (R = -0.552, P = 0.012) and severity (R = -0.783, P < 0.001). CONCLUSION: The cFRDA and LOFA groups have similar, but not identical neuroimaging damage pattern. These structural differences might help to explain the phenotypic variability observed in FRDA. Hum Brain Mapp 38:4157-4168, 2017. © 2017 Wiley Periodicals, Inc.
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Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão , Ataxia de Friedreich/diagnóstico por imagem , Imageamento por Ressonância Magnética , Imagem Multimodal , Adulto , Idade de Início , Atrofia , Progressão da Doença , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Imageamento Tridimensional , Masculino , Tamanho do Órgão , Índice de Gravidade de Doença , Substância Branca/diagnóstico por imagem , Adulto JovemRESUMO
Rasmussen's encephalitis is a devastating syndrome of multifocal brain dysfunction and focal seizures. Magnetic resonance (MR) findings, associated with clinical data and electroencephalogram (EEG), may indicate the diagnosis and could be an indicative of prognosis. We studied 5 patients with Rasmussen's encephalitis, assessing clinical history and MR images. All patients had refractory focal seizures with a predominant motor component associated with hemispheric atrophy, that was proportional to severity of disease and neurological deficits in these patients. Gray and white matter abnormal signal on T2 MR images were found in patients who had hemiparesis. It was not related to the duration of the disease but to aggressiveness. MR proton spectroscopy in severe disease showed lactate and choline increase and decreased NAA, reflecting neuronal and axonal loss, gliosis and elevated membrane turnover and recent - crisis (not controlled). MR studies, in addition to help in diagnosis, may be useful for monitoring metabolic changes and progression of disease in Rasmussen's encephalitis.
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Encefalite/diagnóstico , Imageamento por Ressonância Magnética/métodos , Adolescente , Criança , Eletroencefalografia , Feminino , Humanos , Masculino , Prognóstico , Índice de Gravidade de DoençaRESUMO
Rasmussen's encephalitis is a devastating syndrome of multifocal brain dysfunction and focal seizures. Magnetic resonance (MR) findings, associated with clinical data and electroencephalogram (EEG), may indicate the diagnosis and could be an indicative of prognosis. We studied 5 patients with Rasmussen's encephalitis, assessing clinical history and MR images. All patients had refractory focal seizures with a predominant motor component associated with hemispheric atrophy, that was proportional to severity of disease and neurological deficits in these patients. Gray and white matter abnormal signal on T2 MR images were found in patients who had hemiparesis. It was not related to the duration of the disease but to aggressiveness. MR proton spectroscopy in severe disease showed lactate and choline increase and decreased NAA, reflecting neuronal and axonal loss, gliosis and elevated membrane turnover and recent - crisis (not controlled). MR studies, in addition to help in diagnosis, may be useful for monitoring metabolic changes and progression of disease in Rasmussen's encephalitis.
A encefalite de Rasmussen é uma devastadora síndrome com disfunção cerebral multifocal e convulsões focais. Achados de ressonância magnética (RM), associados aos dados clínicos e de eletrencefalograma (EEG), podem indicar o diagnóstico e podem ser indicativos de prognóstico. Foram estudados 5 pacientes com encefalite de Rasmussen, avaliando a história clínica e imagens de RM. Todos os pacientes apresentavam crises epilépticas focais refratárias com componente predominantemente motor associadas à atrofia hemisférica, que foi proporcional à gravidade da doença e déficits neurológicos nestes pacientes. Alteração da intensidade de sinal nas substâncias branca e cinzenta, nas sequências ponderadas em T2, foram encontradas nos pacientes com hemiparesia. Ela não estava relacionada com a duração da doença, mas à severidade. A espectroscopia de prótons por RM na doença severa demonstrou aumento dos níveis de colina e lactato e diminuição de N-acetilaspartato, refletindo perda neuronal e axonal, gliose e aumento de turnover de membrana e crise recente (não controlada). Estudos de RM, além de ajudar no diagnóstico, podem ser úteis para acompanhar alterações metabólicas e progressão da doença na encefalite de Rasmussen.
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Adolescente , Criança , Feminino , Humanos , Masculino , Encefalite/diagnóstico , Imageamento por Ressonância Magnética/métodos , Eletroencefalografia , Prognóstico , Índice de Gravidade de DoençaRESUMO
BACKGROUND AND PURPOSE: Sensory neuronopathies (SN) represent a specific subgroup of peripheral nervous system diseases, characterized by degeneration of dorsal root ganglia (DRG) and its projections. We tried to estimate the frequency and extent of spinal cord MRI abnormalities in a group of patients with SN and correlate these with clinical and neurophysiological features. METHODS: We performed spinal cord MRI scans in 16 chronic SN patients. Images were analyzed for the presence of posterior hyperintense lesions on T2WI and cord areas at C3 level were obtained using a previously validated method. A group of 14 healthy controls with similar age and gender distribution was used for comparison. ANOVA was employed for statistical analysis. RESULTS: Posterior T2WI lesions were found in 13 out of 16 patients. Cord areas were significantly smaller in SN patients than controls (84.3 x 97.2 mm(2), P < .05). Atrophy correlated with severity of sensory ataxia and neurophysiologic abnormalities but not with duration of disease. CONCLUSIONS: These findings support volumetric spinal cord MRI as a useful tool in the assessment of chronic SN.
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Neuropatias Hereditárias Sensoriais e Autônomas/patologia , Imageamento por Ressonância Magnética/métodos , Medula Espinal/patologia , Análise de Variância , Atrofia , Estudos de Casos e Controles , Doença Crônica , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Modelos Lineares , Masculino , Pessoa de Meia-IdadeRESUMO
Inflammatory myopathies (IM) are a heterogeneous group of diseases characterized by immune-mediated damage to skeletal muscle. Sensory abnormalities are rare in patients with IM. We report two patients, one with dermatomyositis and the other with inclusion-body myositis, who presented with unexpected sensory abnormalities due to probable immune-mediated damage to dorsal root ganglia. We emphasize the importance of combined neuroimaging and neurophysiological assessment for proper diagnosis.
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Miosite/complicações , Doenças do Sistema Nervoso Periférico/complicações , Adulto , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Miosite/patologia , Condução Nervosa/fisiologia , Doenças do Sistema Nervoso Periférico/patologiaRESUMO
Two patients with multifocal pilocytic astrocytoma diagnosed by magnetic resonance imaging (MRI) and confirmed by histopathological examination are reported. They presented distinct sites and mechanisms of metastasis: to distant ventricles through the cerebral spinal fluid (CSF) in patient 1 and to contralateral parenchyma, possibly through white matter tracts, in patient 2, a pathway not so far reported in pilocytic astrocytoma. Early detection of multifocal pilocytic astrocytoma by MRI may change treatment strategies and improve prognosis.
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Astrocitoma/secundário , Neoplasias Encefálicas/patologia , Pré-Escolar , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-IdadeRESUMO
PURPOSE: To investigate imaging findings, risk factors and outcome in patients with cerebral venous thrombosis (CVT). METHODS: Records of all patients with diagnosis of CVT between 1992 and 2002 were reviewed. Patients with CNS infection and with CVT secondary to invasive procedures were excluded. Inherited and acquired thrombophilia were searched in all patients. RESULTS: Twenty-four patients (18 women, 6 men) with mean age of 29.5 years (range 3-48 years) were identified. Mean follow-up was 44 months (range 11-145 months). The most common symptoms were headache (75%), vomiting (33%) and impairment of consciousness (21%). Probable causes of CVT could be determined in 21 (88%) patients: pregnancy or puerperium in six (25%), oral contraceptive use in four (17%), head trauma in two (8%), mastoiditis in one (4%), nephrotic syndrome in one (4%), systemic disease in three (13%), and inherited thrombotic risk factors in four (17%) patients. CVT associated with pregnancy, puerperium and use of oral contraceptives had a significant better outcome than CVT caused by inherited thrombophilia or systemic disease (OR=14.4; p=0.02). CT scans were abnormal in 15 (62.5%) patients and MRI with gadolinium was abnormal in all. Those with parenchymal involvement had neurological sequelae during follow-up. All were treated with heparin followed by oral anticoagulants, and none had new or worsening of pre-existing intracerebral hemorrhage. CONCLUSION: MRI is superior to conventional CT for diagnosing CVT. Patients with parenchymal lesions, thrombophilia and antiphospholipid syndrome had greater risk to be left with neurological sequelae. Anticoagulant therapy did not predispose to further intracerebral hemorrhage.
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Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Trombose Intracraniana/etiologia , Complicações Cardiovasculares na Gravidez/etiologia , Trombofilia/complicações , Trombose Venosa/etiologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Trombose Intracraniana/diagnóstico , Trombose Intracraniana/terapia , Masculino , Pessoa de Meia-Idade , Gravidez , Complicações Cardiovasculares na Gravidez/diagnóstico , Complicações Cardiovasculares na Gravidez/terapia , Radiografia , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Trombose Venosa/diagnóstico , Trombose Venosa/terapiaRESUMO
Os autores apresentam os achados de exames de imagem de 19 pacientes pediátricos com massas abdominais volumosas. Foram selecionadas imagens de ultra-sonografia (US), tomografia computadorizada (TC) e ressonância magnética (RM). Nos 19 pacientes estudados os diagnósticos foram: hidronefrose, tumor de WiIms, neuroblastoma, carcinoma de adrenal, sarcoma, hemangioendotelioma, hepatoblastoma, hamartoma mesenquimal, carcinoma hepatocelular, cisto de colédoco, cisto esplênico, linfoma, cisto de mesentério, teratoma, hidrometrocolpos, lipoma. Os exames de imagem (US, TC e RM) são importantes ferramentas na avaliação de massas abdominais pediátricas e podem contribuir para o diagnóstico e avaliação da extensão dessas entidades.
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Humanos , Pré-Escolar , Criança , Espectroscopia de Ressonância Magnética , Neoplasias Abdominais/patologia , Neoplasias Abdominais , Pediatria , Tomografia Computadorizada por Raios X , Diagnóstico DiferencialRESUMO
We analyzed computerized tomography (CT) findings in six patients with Fahr's syndrome. They presented calcifications in basal ganglia, dentate nucleus, subcortical region and semioval center, due to alteration in calcium metabolism or due to senile relative hypoxemic state. The image pattern was not strictly related with etiology, although some differences in dystrophic senile calcifications (the only one present in semioval center and absent in subcortical region). CT is an easy exam, has maximum sensitivity and allows diagnosis, contributing to early treatment of many etiologies of Fahr's syndrome.
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Doenças dos Gânglios da Base/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Sensibilidade e Especificidade , Síndrome , Tomografia Computadorizada por Raios XRESUMO
The authors describe a patient with brain paracoccidioidomycosis whose magnetic resonance image (MRI) showed multiple hypointense lesions on T2-weighted images with peripheral enhancement after gadolinium injection. Single-voxel proton magnetic resonance spectroscopy (1H-MRS) of one of the lesions showed 2 peaks at 0.9 and 1.32 ppm, corresponding to lipid signals, indicating intense necrosis. The other characteristic peaks of 1H-MRS were undifferentiated from baseline. These findings, although not specific, may help to differentiate fungal abscess from tumoral lesions and other types of abscess.
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Doenças do Sistema Nervoso Central/diagnóstico , Doenças do Sistema Nervoso Central/microbiologia , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Paracoccidioidomicose/diagnóstico , Adulto , Humanos , MasculinoRESUMO
Analisamos os achados de tomografia computadorizada (TC) de seis pacientes com síndrome de Fahr. Eles apresentaram calcificações nos gânglios da base, núcleo denteado, região subcortical e centro semi-oval, devidas a distúrbios no metabolismo do cálcio ou a estado de hipóxia relativa, por senilidade. O padrão de imagem não apresenta relação clara com a etiologia, apesar de algumas diferenças no caso das calcificações distróficas senis (as únicas presentes nos centros semi-ovais e ausentes na região subcortical). TC é um exame de fácil realização, máxima sensibilidade e permite o diagnóstico, contribuindo para o tratamento precoce de muitas das etiologias da síndrome de Fahr.
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Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Doenças dos Gânglios da Base , Calcinose , Sensibilidade e Especificidade , Síndrome , Tomografia Computadorizada por Raios XRESUMO
The purpose of this article is show the role of proton magnetic resonance spectroscopy (MRS), associated with magnetic resonance images, in the study of non-neoplastic disorders, helping in diagnosis and better characterization of the nature of the lesion. Herein, we analyzed single voxel proton spectroscopy in eight different non-neoplastic lesions, displayed in six categories (infectious, ischaemic, demyelinating, inflammatory, malformation of development and phacomatosis). The presence or the ratios of signal intensities brain tissue metabolites observed with this technique (N-acetyl aspartate, choline, creatine, lactate and lipids) helped in their differentiation with neoplastic lesions and helped in correct diagnosis. In infectious diseases, signals of acetate, succinate and amino acids were also important. In conclusion, proton MRS is a noninvasive method, very useful as an additional technique to define the nature of non-neoplastic encephalic lesions.
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Encefalopatias/diagnóstico , Espectroscopia de Ressonância Magnética/métodos , Prótons , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , MasculinoRESUMO
O propósito deste artigo é mostrar o valor da espectroscopia de hidrogênio associada a imagens de ressonância magnética (RM), no estudo de lesões encefálicas não neoplásicas, ajudando no diagnostico e na melhor caracterização de grupos etiológicos. Analisamos espectroscopias de hidrogênio com voxel único em oito diferentes doenças não neoplásicas, divididas em seis categorias (infecciosas, isquêmicas, desmielinizates, inflamatórias, malformações do desenvolvimento cortical e facomatoses). A presença e as relações entre a intensidade do sinal dos metabólitos do tecido nervoso observados com esta técnica (N-acetil aspartato, colina, creatina, lactato e lipídios) ajudaram na diferenciação de lesões neoplásicas e permitiram o diagnostico correto. Nas doenças infecciosas, os sinais do acetato, succinato e aminoácidos também foram importantes. Concluímos que a espectroscopia do hidrogênio por RM é um método não invasivo muito útil como técnica adicional para definir a natureza não neoplásica de lesões encefálicas.