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Síndrome de Sjogren , Humanos , Síndrome de Sjogren/complicações , Síndrome de Sjogren/diagnóstico , Feminino , Resultado do Tratamento , Vasculite do Sistema Nervoso Central/diagnóstico , Vasculite do Sistema Nervoso Central/etiologia , Pessoa de Meia-Idade , Imageamento por Ressonância MagnéticaRESUMO
OBJECTIVE: To evaluate whether a higher proportion of enteral vs parenteral protein ratio (E:P ratio) in the first 28 days after birth is associated with increased brain volume and somatic growth in very low birth weight (VLBW; birth weight <1500 g) infants. STUDY DESIGN: This was a retrospective analysis of a subcohort of VLBW infants (n = 256, gestational age mean 28.07 [SD 2.17] weeks, birth weight 1038.80 [SD 262.95] grams) from the Cincinnati Infant Neurodevelopment Early Prediction Study, a regional prospective study of infants born at ≤32 weeks' gestation. Brain magnetic resonance imaging was obtained at term-equivalent age. Macronutrient intake and growth metrics for the first 28 days were collected retrospectively. The primary outcome was total brain tissue volume. The relationships between E:P ratio, total and regional brain tissue volumes, and somatic growth were analyzed by multivariable linear regression models; composite variables were used to adjust for potential confounders including pregnancy risk factors and initial severity of illness. RESULTS: Higher E:P ratio was associated with increased total brain tissue volume but was not associated with change in head circumference z score. In secondary analyses, higher E:P ratio was associated with increased weight velocity. There were no significant associations between E:P ratio and change in weight or length z scores or regional brain volumes. CONCLUSIONS: Higher E:P ratio in the first 28 days was positively associated with total brain volume and weight gain. Promoting the provision of enteral over parenteral protein may improve brain and somatic growth in VLBW infants.
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PURPOSE: To characterize Vanishing White Matter Disease (VWM) cases from a Brazilian University Tertiary hospital, focusing on brain magnetic resonance image (MRI) aspects, clinical and molecular data. METHODS: Medical records and brain MRI of 13 genetically confirmed VWM patients were reviewed. Epidemiological data such as age at symptom onset, gender and main symptoms were analyzed, along with genetic mutations and MRI characteristics, such as the distribution of white matter lesions and atrophy. RESULTS: The majority of patients were female, with the age of symptom onset ranging from 1 year and 6 months to 40 years. All mutations were identified in the EIF2B5 gene, the most prevalent being c.338G > A (p.Arg113His), and a novel mutation related to the disease was discovered, c.1051G > A (p.Gly351Ser). Trauma or infection were significant triggers. The most frequent symptoms were ataxia and limb spasticity. All MRI scans displayed deep white matter involvement, cystic degeneration, with U-fibers relatively spared and a predilection for the frontoparietal region. Lesions in the corpus callosum and posterior fossa were present in all patients. Follow-up exams revealed the evolution of white matter lesions and cerebral atrophy, which correlated with clinical deterioration. CONCLUSIONS: VWM affects various age groups, with a significant clinical and genetic variability. A novel mutation associated with the disease is highlighted. MRI reveals a typical pattern of white matter involvement, characterized by diffuse lesions in the periventricular and deep regions, with subsequent extension to the subcortical areas, accompanied by cystic degeneration, and plays a crucial role in diagnosis and follow-up.
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Leucoencefalopatias , Imageamento por Ressonância Magnética , Humanos , Feminino , Masculino , Brasil , Adulto , Leucoencefalopatias/diagnóstico por imagem , Leucoencefalopatias/genética , Criança , Adolescente , Imageamento por Ressonância Magnética/métodos , Lactente , Pré-Escolar , Mutação , Adulto Jovem , Fator de Iniciação 2B em Eucariotos/genéticaRESUMO
Data collection, curation, and cleaning constitute a crucial phase in Machine Learning (ML) projects. In biomedical ML, it is often desirable to leverage multiple datasets to increase sample size and diversity, but this poses unique challenges, which arise from heterogeneity in study design, data descriptors, file system organization, and metadata. In this study, we present an approach to the integration of multiple brain MRI datasets with a focus on homogenization of their organization and preprocessing for ML. We use our own fusion example (approximately 84,000 images from 54,000 subjects, 12 studies, and 88 individual scanners) to illustrate and discuss the issues faced by study fusion efforts, and we examine key decisions necessary during dataset homogenization, presenting in detail a database structure flexible enough to accommodate multiple observational MRI datasets. We believe our approach can provide a basis for future similarly-minded biomedical ML projects.
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Brain tissue segmentation in magnetic resonance imaging volumes is an important image processing step for analyzing the human brain. This paper presents a novel approach named Pseudo-Label Assisted Self-Organizing Map (PLA-SOM) that enhances the result produced by a base segmentation method. Using the output of a base method, PLA-SOM calculates pseudo-labels in order to keep inter-class separation and intra-class compactness in the training phase. For the mapping phase, PLA-SOM uses a novel fuzzy function that combines feature space learned by the SOM's prototypes, topological ordering from the map, and spatial information from a brain atlas. We assessed PLA-SOM performance on synthetic and real MRIs of the brain, obtained from the BrainWeb and the Internet Brain Image Repository datasets. The experimental results showed evidence of segmentation improvement achieved by the proposed method over six different base methods. The best segmentation improvements reported by PLA-SOM on synthetic brain scans are 11%, 6%, and 4% for the tissue classes cerebrospinal fluid, gray matter, and white matter, respectively. On real brain scans, PLA-SOM achieved segmentation enhancements of 15%, 5%, and 12% for cerebrospinal fluid, gray matter, and white matter, respectively.
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Encéfalo , Imageamento por Ressonância Magnética , Algoritmos , Encéfalo/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , PoliésteresRESUMO
Background: The neutrophil-to-lymphocyte ratio (NLR) has been investigated in many autoimmune conditions as a biomarker of inflammation and/or disease activity. The role of NLR in AQP4-IgG-positive neuromyelitis optica spectrum disorders (NMOSD) is far from clear. In this study, NLR was evaluated in patients with AQP4-IgG-positive NMOSD at disease onset and its prognostic impact was subsequently assessed. Methods: In this multicenter study, we retrospectively included all recent/newly diagnosed treatment-naïve patients with AQP4-IgG-positive NMOSD (n=90) from three different countries in Latin America (LATAM): Argentina, Ecuador, and Mexico. NLR was compared between AQP4-IgG-positive NMOSD and healthy controls (HC, n = 365). Demographic, clinical, paraclinical (including imaging), and prognostic data at 12 and 24 months were also evaluated. Multivariate regression analysis was used to describe and identify independent associations between the log-transformed NLR and clinical (relapses and EDSS) and imaging (new/enlarging and/or contrast-enhancing MRI lesions) outcomes. Results: NLR was higher in NMOSD patients during the first attack compared with HC (2.9 ± 1.6 vs 1.8 ± 0.6; p<0.0001). Regardless of immunosuppressant's initiation at disease onset, NLR remained higher in NMOSD patients at 12 (2.8 ± 1.3; p<0.0001) and 24 (3.1 ± 1.6; p<0.0001) months. No association was found at 12 and 24 months between the log-transformed NLR and the presence of relapses, new/enlarging and/or contrast-enhancing MRI lesions, and/or physical disability. Conclusions: In this cohort of LATAM patients with AQP4-IgG-positive NMOSD, NLR was abnormally high in attacks but also during follow-up. However, a high NLR was not an independent predictor of clinical or imaging outcomes in our models.
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Aquaporina 4/imunologia , Autoanticorpos/sangue , Linfócitos/imunologia , Neuromielite Óptica/imunologia , Neutrófilos/imunologia , Adulto , Argentina , Equador , Feminino , Humanos , Imunoglobulina G/sangue , Imunossupressores/uso terapêutico , Contagem de Linfócitos , Masculino , México , Pessoa de Meia-Idade , Neuromielite Óptica/sangue , Neuromielite Óptica/diagnóstico por imagem , Neuromielite Óptica/tratamento farmacológico , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Testes SorológicosRESUMO
Neurologic complications are being recognized as important outcomes of coronavirus disease 2019 (COVID-19). Pathogenesis is varied and incompletely understood, and may include neuroinvasion, indirect post-infectious neuroinflammation, and cerebrovascular pathologies. We present a case of COVID-19-related encephalomyeloradiculitis with clinical and magnetic resonance imaging characteristics of neuromyelitis optica spectrum disorders that was associated with anti-aquaporin-4 antibodies. Our case suggests post-infectious autoimmunity as a mechanism in at least a subset of patients with COVID-19-related neurologic disease.
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Aquaporina 4/imunologia , Autoanticorpos/análise , Doenças Autoimunes/etiologia , COVID-19/complicações , Encefalomielite/etiologia , Radiculopatia/etiologia , Azatioprina/uso terapêutico , Encéfalo/diagnóstico por imagem , COVID-19/diagnóstico por imagem , Encefalomielite/diagnóstico por imagem , Encefalomielite/imunologia , Feminino , Humanos , Imunossupressores/uso terapêutico , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Neuromielite Óptica/diagnóstico por imagem , Neuromielite Óptica/etiologia , Troca Plasmática , Radiculopatia/diagnóstico por imagem , Radiculopatia/imunologia , Coluna Vertebral/diagnóstico por imagemRESUMO
This paper presents a novel unsupervised algorithm for brain tissue segmentation in magnetic resonance imaging (MRI). The proposed algorithm, named Gardens2, adopts a clustering approach to segment voxels of a given MRI into three classes: cerebrospinal fluid (CSF), gray matter (GM), and white matter (WM). Using an overlapping criterion, 3D feature descriptors and prior atlas information, Gardens2 generates a segmentation mask per class in order to parcellate the brain tissues. We assessed our method using three neuroimaging datasets: BrainWeb, IBSR18, and IBSR20, the last two provided by the Internet Brain Segmentation Repository. Its performance was compared with eleven well established as well as newly proposed unsupervised segmentation methods. Overall, Gardens2 obtained better segmentation performance than the rest of the methods in two of the three databases and competitive results when its performance was measured by class. Graphical Abstract Brain tissue segmentation using 3D features and an adjusted atlas template.
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Encéfalo , Imageamento por Ressonância Magnética , Algoritmos , Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , NeuroimagemRESUMO
Chikungunya virus can be transmitted perinatally leading to serious neurological sequelae. We report the longitudinal evolution of the brain magnetic resonance imaging aspects of three cases of mother-to-child Chikungunya virus transmission. The first magnetic resonance imaging scan presented brain cavitations, with or without corpus callosum diffusion restriction. Follow-up scans showed reduction in the volume of cavitations, with resolution of the restricted diffusion. However, one patient presented with a normal brain magnetic resonance image, despite the delay in neurocognitive development.
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Febre de Chikungunya/diagnóstico por imagem , Febre de Chikungunya/transmissão , Transmissão Vertical de Doenças Infecciosas , Imageamento por Ressonância Magnética/métodos , Adulto , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , GravidezRESUMO
PURPOSE OF REVIEW: Space-occupying lesions represent a diagnostic challenge among people with the human immunodeficiency virus, acquired immunodeficiency syndrome (HIV/AIDS). To determine the best diagnostic approach to the wide array of possible etiologies and provide a thorough interpretation of neuroimaging in order to narrow a hierarchical differential diagnosis among these patients. Given that there is no pathognomonic neuroimaging pattern in this clinical setting, we searched results from brain biopsies to best determine the etiology of commonly found lesions. RECENT FINDINGS: Multimodal brain MRI and MRI spectroscopy (MRS) often provide the most valuable information in the study of focal masses among people with HIV/AIDS. Brain biopsy appears safe and provides high diagnostic yields in these patients. Among patients with HIV/AIDS who present with space-occupying intracranial lesions, brain MRI and MRS are useful tests. However, in cases of diagnostic uncertainty, brain biopsy is a safe procedure and should be performed. The role of metabolic studies like 201Th-SPECT or PET is useful in the detection of primary central nervous system lymphoma.
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Infecções Oportunistas Relacionadas com a AIDS , Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Toxoplasmose Cerebral , Infecções por HIV/complicações , Infecções por HIV/diagnóstico por imagem , Humanos , Imageamento por Ressonância MagnéticaRESUMO
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
BACKGROUND: Congenital Zika virus (ZIKV) infection can be detected in both the presence and absence of microcephaly and manifests as a number of signs and symptoms that are detected clinically and by neuroimaging. However, to date, qualitative and quantitative measures for the purpose of diagnosis and prognosis are limited. OBJECTIVES: Main objectives of this study conducted on fetuses and infants with confirmed congenital Zika virus infection and detected brain abnormalities were (1) to assess the prevalence of microcephaly and the frequency of the anomalies that include a detailed description based on ultrasound and magnetic resonance imaging in fetuses and ultrasound, magnetic resonance imaging, and computed tomography imaging postnatally, (2) to provide quantitative measures of fetal and infant brain findings by magnetic resonance imaging with the use of volumetric analyses and diffusion-weighted imaging, and (3) to obtain additional information from placental and fetal histopathologic assessments and postnatal clinical evaluations. STUDY DESIGN: This is a longitudinal cohort study of Zika virus-infected pregnancies from a single institution in Colombia. Clinical and imaging findings of patients with laboratory-confirmed Zika virus infection and fetal brain anomalies were the focus of this study. Patients underwent monthly fetal ultrasound scans, neurosonography, and a fetal magnetic resonance imaging. Postnatally, infant brain assessment was offered by the use of ultrasound imaging, magnetic resonance imaging, and/or computed tomography. Fetal head circumference measurements were compared with different reference ranges with <2 or <3 standard deviations below the mean for the diagnosis of microcephaly. Fetal and infant magnetic resonance imaging images were processed to obtain a quantitative brain volumetric assessment. Diffusion weighted imaging sequences were processed to assess brain microstructure. Anthropometric, neurologic, auditory, and visual assessments were performed postnatally. Histopathologic assessment was included if patients opted for pregnancy termination. RESULTS: All women (n=214) had been referred for Zika virus symptoms during pregnancy that affected themselves or their partners or if fetal anomalies that are compatible with congenital Zika virus syndrome were detected. A total of 12 pregnant patients with laboratory confirmation of Zika virus infection were diagnosed with fetal brain malformations. Most common findings that were assessed by prenatal and postnatal imaging were brain volume loss (92%), calcifications (92%), callosal anomalies (100%), cortical malformations (89%), and ventriculomegaly (92%). Results from fetal brain volumetric assessment by magnetic resonance imaging showed that 1 of the most common findings associated with microcephaly was reduced supratentorial brain parenchyma and increased subarachnoid cerebrospinal fluid. Diffusion weighted imaging analyses of apparent diffusion coefficient values showed microstructural changes. Microcephaly was present in 33.3-58.3% of the cases at referral and was present at delivery in 55.6-77.8% of cases. At birth, most of the affected neonates (55.6-77.8%) had head circumference measurements >3 standard deviations below the mean. Postnatal imaging studies confirmed brain malformations that were detected prenatally. Auditory screening results were normal in 2 cases that were assessed. Visual screening showed different anomalies in 2 of the 3 cases that were examined. Pathologic results that were obtained from 2 of the 3 cases who opted for termination showed similar signs of abnormalities in the central nervous system and placental analyses, including brain microcalcifications. CONCLUSION: Congenital microcephaly is not an optimal screening method for congenital Zika virus syndrome, because it may not accompany other evident and preceding brain findings; microcephaly could be an endpoint of the disease that results from progressive changes that are related to brain volume loss. Long-term studies are needed to understand the clinical and developmental relevance of these findings.
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Encéfalo/anormalidades , Encéfalo/diagnóstico por imagem , Complicações Infecciosas na Gravidez/epidemiologia , Infecção por Zika virus/epidemiologia , Adolescente , Adulto , Calcinose/diagnóstico por imagem , Líquido Cefalorraquidiano/fisiologia , Estudos de Coortes , Colômbia/epidemiologia , Diagnóstico por Imagem , Potenciais Evocados Auditivos , Potenciais Evocados Visuais , Feminino , Humanos , Hidrocefalia/diagnóstico por imagem , Recém-Nascido , Estudos Longitudinais , Microcefalia/virologia , Gravidez , Espaço Subaracnóideo/fisiologia , Adulto Jovem , Infecção por Zika virus/congênitoRESUMO
BACKGROUND: Very little is known about the incidence and prevalence of hydrocephalus in patients with mucopolysaccharidoses (MPS). The biggest challenge is to distinguish communicating hydrocephalus from ventricular dilatation secondary to brain atrophy, because both conditions share common clinical and neuroradiological features. The main purpose of this study is to assess the relationship between ventriculomegaly, brain and cerebrospinal fluid (CSF) volumes, aqueductal and cervical CSF flows, and CSF opening pressure in MPS patients, and to provide potential biomarkers for abnormal CSF circulation. METHODS: Forty-three MPS patients (12 MPS I, 15 MPS II, 5 MPS III, 9 MPS IV A and 2 MPS VI) performed clinical and developmental tests, and T1, T2, FLAIR and phase-contrast magnetic resonance imaging (MRI) followed by a lumbar puncture with the CSF opening pressure assessment. For the analysis of MRI variables, we measured the brain and CSF volumes, white matter (WM) lesion load, Evans' index, third ventricle width, callosal angle, dilated perivascular spaces (PVS), craniocervical junction stenosis, aqueductal and cervical CSF stroke volumes, and CSF glycosaminoglycans concentration. RESULTS: All the scores used to assess the supratentorial ventricles enlargement and the ventricular CSF volume presented a moderate correlation with the aqueductal CSF stroke volume (ACSV). The CSF opening pressure did not correlate either with the three measures of ventriculomegaly, or the ventricular CSF volume, or with the ACSV. Dilated PVS showed a significant association with the ventriculomegaly, ventricular CSF volume and elevated ACSV. CONCLUSIONS: In MPS patients ventriculomegaly is associated with a severe phenotype, increased cognitive decline, WM lesion severity and enlarged PVS. The authors have shown that there are associations between CSF flow measurements and measurements related to CSF volumetrics. There was also an association of volumetric measurements with the degree of dilated PVS.
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Hidrocefalia/complicações , Hidrocefalia/epidemiologia , Mucopolissacaridoses/líquido cefalorraquidiano , Mucopolissacaridoses/complicações , Adolescente , Adulto , Líquido Cefalorraquidiano , Pressão do Líquido Cefalorraquidiano , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Hidrocefalia/diagnóstico por imagem , Lactente , Imageamento por Ressonância Magnética , Masculino , Neuroimagem/métodos , Adulto JovemRESUMO
INTRODUCTION: The precise incidence of hydrocephalus in patients with mucopolysaccharidoses (MPS) is hard to determine, because the condition lacks a formal, consensus-based definition. The diagnosis of hydrocephalus depends on symptom profile, presence of neuroimaging features, and the outcome of diagnostic tests. Although numerous techniques are used to identify MPS patients who are most likely to have hydrocephalus and respond to treatment, no definitive method exists to prove diagnosis. PURPOSE: The authors propose an algorithm to aid in the diagnosis and management of hydrocephalus in MPS patients. CONCLUSIONS: The theory of venous hypertension associated with the morphological changes in the skull base and craniocervical junction indicate the need for future neuroimaging studies including cerebrospinal fluid (CSF) and venous flow measurements to monitor hydrocephalus progression and select therapeutic interventions in MPS patients. Preoperative planning should also be based on the increased risk of intraoperative and postoperative hemorrhagic complications.
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Hidrocefalia/complicações , Mucopolissacaridoses/complicações , Algoritmos , Encéfalo/diagnóstico por imagem , Humanos , Hidrocefalia/líquido cefalorraquidiano , Hidrocefalia/diagnóstico , Hidrocefalia/cirurgia , Mucopolissacaridoses/líquido cefalorraquidiano , Mucopolissacaridoses/diagnóstico , Mucopolissacaridoses/cirurgia , VentriculostomiaRESUMO
The chronic health effects associated with sustained exposures to high concentrations of air pollutants are an important issue for millions of megacity residents and millions more living in smaller urban and rural areas. Particulate matter (PM) and ozone (O3) concentrations close or above their respective air quality standards during the last 20 years affect 24 million people living in the Mexico City Metropolitan Area (MCMA). Herein we discuss PM and O3 trends in MCMA and their possible association with the observed central nervous system (CNS) effects in clinically healthy children. We argue that prenatal and postnatal sustained exposures to a natural environmental exposure chamber contribute to detrimental neural responses. The emerging picture for MCMA children shows systemic inflammation, immunodysregulation at both systemic and brain levels, oxidative stress, neuroinflammation, small blood vessel pathology, and an intrathecal inflammatory process, along with the early neuropathological hallmarks for Alzheimer and Parkinson's diseases. Exposed brains are briskly responding to their harmful environment and setting the bases for structural and volumetric changes, cognitive, olfactory, auditory and vestibular deficits and long term neurodegenerative consequences. We need to improve our understanding of the PM pediatric short and long term CNS impact through multidisciplinary research. Public health benefit can be achieved by integrating interventions that reduce fine PM levels and pediatric exposures and establishing preventative screening programs targeting pediatric populations that are most at risk. We fully expect that the health of 24 million residents is important and blocking pediatric air pollution research and hiding critical information that ought to be available to our population, health, education and social workers is not in the best interest of our children.
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Poluentes Atmosféricos/toxicidade , Sistema Nervoso Central/efeitos dos fármacos , Exposição Ambiental , Ozônio/toxicidade , Material Particulado/toxicidade , Criança , Pré-Escolar , Cidades , Monitoramento Ambiental , Humanos , México , Saúde da População UrbanaRESUMO
Posterior reversible encephalopathy syndrome (PRES) is a clinicoradiologic entity not yet understood, that is present with transient neurologic symptoms and particular radiological findings. The most common imaging pattern in PRES is the presence of edema in the white matter of the posterior portions of both cerebral hemispheres. The cause of PRES is unclear. We report a case of 13-year-old male who was stung by a scorpion and developed a severe headache, visual disturbance, and seizures and had the diagnosis of PRES with a good outcome. Numerous factors can trigger this syndrome, most commonly: acute elevation of blood pressure, abnormal renal function, and immunosuppressive therapy. There are many cases described showing the relationship between PRES and eclampsia, transplantation, neoplasia and chemotherapy treatment, systemic infections, renal disease acute, or chronic. However, this is the first case of PRES following a scorpion sting.