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BACKGROUND: Anti-myelin oligodendrocyte glycoprotein (anti-MOG) antibody-associated disease (MOGAD) is an immune-mediated neurological disorder with a broad spectrum of clinical presentation that is often difficult to distinguish from other demyelinating diseases, such as multiple sclerosis and neuromyelitis optica spectrum disorder. OBJECTIVE: To describe the clinical and paraclinical characteristics of MOGAD in a Brazilian tertiary center. METHODS: We retrospectively reviewed the records of adult and pediatric patients who tested positive for anti-MOG antibodies and presented with clinical and radiological diseases compatible with MOGAD. RESULTS: Forty-one patients (10 children) were included: 56% female, 58% Caucasian, mean age at onset 31 years (range 6-64), with a mean disease duration of 59.6 months (range 1-264 months). The most frequent onset presentation was optic neuritis (68%), acute disseminated encephalomyelitis (ADEM, 12%), and myelitis (10%). A monophasic disease course was observed in 49%. EDSS median was 2.1 at the last visit. Most patients (83%) were under continuous immunosuppressive treatment. Azathioprine was the first-line treatment in 59%. In all ADEM cases, conus, and root involvement was radiologically observed on MRI. CONCLUSION: Brazilian MOGAD patients presented with a similar spectrum of previously reported MOGAD phenotypes. Conus and spinal root involvement seems to be frequently present in MOGAD-ADEM and could serve as radiologic characteristics of this clinical entity.

ANTECEDENTES: A doença associada ao anticorpo da glicoproteína da mielina de oligodendrócitos (anti-MOG; MOGAD) é uma doença neurológica imunomediada com um amplo espectro de apresentações clínicas que muitas vezes é difícil de distinguir de outras doenças desmielinizantes, como a esclerose múltipla e o distúrbio do espectro da neuromielite óptica. OBJETIVO: Descrever as características clínicas e paraclínicas da MOGAD em um centro terciário brasileiro. MéTODOS: Revisamos retrospectivamente os prontuários dos pacientes adultos e pediátricos que testaram positivos para anticorpos anti-MOG e apresentaram um quadro clínico e radiológico compatível com MOGAD. RESULTADOS: Quarenta e um pacientes (10 crianças) foram incluídos: 56% do sexo feminino, 58% caucasianos, idade média de início da doença foi 31 anos (intervalo de 6-64), com duração média da doença de 59,6 meses (intervalo de 1-264 meses). A apresentação inicial mais frequente foi neurite óptica (68%), seguida pela encefalomielite disseminada aguda (ADEM, 12%) e mielite (10%). Um curso monofásico da doença foi observado em 49%. EDSS foi de 2,1 na última visita. A maioria dos pacientes (83%) estava sob tratamento imunossupressor contínuo. Azatioprina foi o tratamento de primeira linha em 59%. Em todos os casos de ADEM, o envolvimento do cone medular e das raízes espinhais foi observado radiologicamente na ressonância magnética. CONCLUSãO: Os pacientes brasileiros com MOGAD apresentam um espectro clínico e radiológico semelhante aos fenótipos de MOGAD relatados anteriormente. O envolvimento do cone e das raízes espinhais parece estar frequentemente presente no MOGAD-ADEM e poderia servir como característica radiológica nesta entidade.

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Abstract Background Anti-myelin oligodendrocyte glycoprotein (anti-MOG) antibody-associated disease (MOGAD) is an immune-mediated neurological disorder with a broad spectrum of clinical presentation that is often difficult to distinguish from other demyelinating diseases, such as multiple sclerosis and neuromyelitis optica spectrum disorder. Objective To describe the clinical and paraclinical characteristics of MOGAD in a Brazilian tertiary center. Methods We retrospectively reviewed the records of adult and pediatric patients who tested positive for anti-MOG antibodies and presented with clinical and radiological diseases compatible with MOGAD. Results Forty-one patients (10 children) were included: 56% female, 58% Caucasian, mean age at onset 31 years (range 6-64), with a mean disease duration of 59.6 months (range 1-264 months). The most frequent onset presentation was optic neuritis (68%), acute disseminated encephalomyelitis (ADEM, 12%), and myelitis (10%). A monophasic disease course was observed in 49%. EDSS median was 2.1 at the last visit. Most patients (83%) were under continuous immunosuppressive treatment. Azathioprine was the first-line treatment in 59%. In all ADEM cases, conus, and root involvement was radiologically observed on MRI. Conclusion Brazilian MOGAD patients presented with a similar spectrum of previously reported MOGAD phenotypes. Conus and spinal root involvement seems to be frequently present in MOGAD-ADEM and could serve as radiologic characteristics of this clinical entity.

Resumo Antecedentes A doença associada ao anticorpo da glicoproteína da mielina de oligodendrócitos (anti-MOG; MOGAD) é uma doença neurológica imunomediada com um amplo espectro de apresentações clínicas que muitas vezes é difícil de distinguir de outras doenças desmielinizantes, como a esclerose múltipla e o distúrbio do espectro da neuromielite óptica. Objetivo Descrever as características clínicas e paraclínicas da MOGAD em um centro terciário brasileiro. Métodos Revisamos retrospectivamente os prontuários dos pacientes adultos e pediátricos que testaram positivos para anticorpos anti-MOG e apresentaram um quadro clínico e radiológico compatível com MOGAD. Resultados Quarenta e um pacientes (10 crianças) foram incluídos: 56% do sexo feminino, 58% caucasianos, idade média de início da doença foi 31 anos (intervalo de 6-64), com duração média da doença de 59,6 meses (intervalo de 1-264 meses). A apresentação inicial mais frequente foi neurite óptica (68%), seguida pela encefalomielite disseminada aguda (ADEM, 12%) e mielite (10%). Um curso monofásico da doença foi observado em 49%. EDSS foi de 2,1 na última visita. A maioria dos pacientes (83%) estava sob tratamento imunossupressor contínuo. Azatioprina foi o tratamento de primeira linha em 59%. Em todos os casos de ADEM, o envolvimento do cone medular e das raízes espinhais foi observado radiologicamente na ressonância magnética. Conclusão Os pacientes brasileiros com MOGAD apresentam um espectro clínico e radiológico semelhante aos fenótipos de MOGAD relatados anteriormente. O envolvimento do cone e das raízes espinhais parece estar frequentemente presente no MOGAD-ADEM e poderia servir como característica radiológica nesta entidade.

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Around 30% of the general population experience subjective tinnitus, characterized by conscious attended awareness perception of sound without an external source. Clinical distress tinnitus is more than just experiencing a phantom sound, as it can be highly disruptive and debilitating, leading those affected to seek clinical help. Effective tinnitus treatments are crucial for psychological well-being, but our limited understanding of the underlying neural mechanisms and a lack of a universal cure necessitate further treatment development. In light of the neurofunctional tinnitus model predictions and transcranial electrical stimulation, we conducted an open-label, single-arm, pilot study that utilized high-definition transcranial direct current stimulation (HD-tDCS) concurrent with positive emotion induction (PEI) techniques for ten consecutive sessions to down-regulate tinnitus negative valence in patients with clinical distress tinnitus. We acquired resting-state functional magnetic resonance imaging scans of 12 tinnitus patients (7 females, mean age = 51.25 ± 12.90 years) before and after the intervention to examine resting-state functional connectivity (rsFC) alterations in specific seed regions. The results showed reduced rsFC at post-intervention between the attention and emotion processing regions as follows: (1) bilateral amygdala and left superior parietal lobule (SPL), (2) left amygdala and right SPL, (3) bilateral dorsolateral prefrontal cortex (dlPFC) and bilateral pregenual anterior cingulate cortex (pgACC), and (4) left dlPFC and bilateral pgACC (FWE corrected p < 0.05). Furthermore, the post-intervention tinnitus handicap inventory scores were significantly lower than the pre-intervention scores (p < 0.05). We concluded that concurrent HD-tDCS and PEI might be effective in reducing tinnitus negative valence, thus alleviating tinnitus distress.

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BACKGROUND: Repeated migraine attacks and aura could independently cause structural changes in the central nervous system. Our research aims to study the correlation of migraine type, attack frequency, and other clinical variables with the presence, volume and localization of white matter lesions (WML), in a controlled study. METHODS: Sixty volunteers from a tertiary headache center were selected and divided equally into four groups: episodic migraine without aura (MoA), episodic migraine with aura (MA), chronic migraine (CM) and controls (CG). Voxel-based morphometry techniques were used to analyze WML. RESULTS: There were no differences in WML variables between groups. There was a positive correlation between age and the number and total volume of WMLs, which persisted in the comparison categorized by size and brain lobe. Disease duration was positively correlated with the number and total volume of WML, and when controlled by age, the correlation maintained significance only for the insular lobe. Aura frequency was associated with frontal and temporal lobe WMLs. There was no statistically significant correlation between WML and other clinical variables. CONCLUSION: Migraine overall is not a risk factor for WML. Aura frequency is, however, associated with temporal WML. Disease duration, in adjusted analyses that account for age, is associated with insular WML.

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OBJECTIVE: To explore pituitary tumors by methylome and transcriptome signatures in a heterogeneous ethnic population. METHODS: In this retrospective cross-sectional study, clinicopathological features, methylome, and transcriptome were evaluated in pituitary tumors from 77 patients (61% women, age 12-72 years) followed due to functioning (FPT: GH-secreting n = 18, ACTH-secreting n = 14) and nonfunctioning pituitary tumors (NFPT, n = 45) at Ribeirao Preto Medical School, University of São Paulo. RESULTS: Unsupervised hierarchical clustering analysis (UHCA) of methylome (n = 77) and transcriptome (n = 65 out of 77) revealed 3 clusters each: one enriched by FPT, one by NFPT, and a third by ACTH-secreting and NFPT. Comparison between each omics-derived clusters identified 3568 and 5994 differentially methylated and expressed genes, respectively, which were associated with each other, with tumor clinical presentation, and with 2017 and 2022 WHO classifications. UHCA considering 11 transcripts related to pituitary development/differentiation also supported 3 clusters: POU1F1-driven somatotroph, TBX19-driven corticotroph, and NR5A1-driven gonadotroph adenomas, with rare exceptions (NR5A1 expressed in few GH-secreting and corticotroph silent adenomas; POU1F1 in few ACTH-secreting adenomas; and TBX19 in few NFPTs). CONCLUSION: This large heterogenic ethnic Brazilian cohort confirms that integrated methylome and transcriptome signatures classify FPT and NFPT, which are associated with clinical presentation and tumor invasiveness. Moreover, the cluster NFPT/ACTH-secreting adenomas raises interest regarding tumor heterogeneity, supporting the challenge raised by the 2017 and 2022 WHO definition regarding the discrepancy, in rare cases, between clinical presentation and pituitary lineage markers. Finally, making our data publicly available enables further studies to validate genes/pathways involved in pituitary tumor pathogenesis and prognosis.

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ABSTRACT: CBF measured with Arterial Spin Labeling (ASL) obtained by Magnetic Resonance Imaging (MRI) may become an important biomarker by showing changes in early stages of AD, such as in the prodromal stage of Mild Cognitive Impairment (MCI). Objective: Verify the correlation between atrophy and CBF in patients with MCI and mild phase ADD, to demonstrate whether changes in CBF can be considered as vascular biomarkers in the diagnosis of the DA continuum. Methods: 11 healthy volunteers, 16 MCI and 15 mild ADD were evaluated. Images of the brain were acquired, including CBF measured with Arterial Spin Labeling (ASL). Results: When comparing MCI with control, a reduction in normalized CBF was observed in left posterior cingulate (estimated difference -0.38; p=0.02), right posterior cingulate (estimated difference -0.45; p=0.02) and right precuneus (estimated difference -0.28; p <0.01); also increase in normalized CBF in right upper temporal pole (estimated difference 0.22; p=0.03). It was also observed that in MCI, the smaller the gray matter volume, the smaller the CBF in the left posterior cingulate; as well as the greater the cerebrospinal fluid volume, consequent to the encephalic volumetric reduction associated with atrophy, the greater the CBF in the right superior temporal pole. When comparing controls, MCI and mild AD, in relation to the other variables, no other correlations were observed between CBF and atrophy. Conclusion: In patients with MCI, the reduction of CBF in the left posterior cingulate correlated with gray matter atrophy, as well as the increase of CBF in the right upper temporal pole correlated with an increase in cerebrospinal fluid consequent to the encephalic volumetric reduction associated with atrophy, demonstrating the influence of CBF in AD related brain atrophy. These findings position CBF as a possible vascular biomarker for early-stage AD diagnoses.

RESUMO: A imagem por ressonância magnética (IRM) pode se tornar um importante biomarcador ao mostrar alterações nos estágios iniciais da doença de Alzheimer (DA). Objetivo: Sendo a atrofia cerebral um importante biomarcador de neurodegeneração na DA, o presente estudo foi realizado com o objetivo de verificar se há correlação entre atrofia e fluxo sanguíneo cerebral (FSC) em pacientes com diagnóstico de CCL e demência da doença de Alzheimer (DDA) leve, com o objetivo de revelar se as alterações no FSC podem ser consideradas possíveis biomarcadores vasculares no diagnóstico do continuum da DA. Métodos: Foram avaliados 11 voluntários saudáveis, 16 CCL e 15 DDA leve. Imagens do cérebro foram adquiridas em um equipamento de 3 T, incluindo imagens ponderadas em T1 de alta resolução para avaliação anatômica e Arterial Spin Labeling (ASL) para a quantificação de FSC. Resultados: Quando comparado CCL com controle, observou-se redução no FSC normalizado em cingulado posterior esquerdo (diferença estimada de -0,38; p=0,02), cingulado posterior direito (diferença estimada de -0,45; p=0,02) e precúneo direito (diferença estimada de -0,28; p <0,01); e aumento de FSC normalizado no polo temporal superior direito (diferença estimada de 0,22; p=0,03). No CCL, quanto menor o volume da substância cinzenta, menor o FSC no cingulado posterior esquerdo; quanto maior o volume de fluido cerebroespinhal, consequente à redução volumétrica encefálica, maior o FSC no polo temporal superior direito. Conclusão: Nos pacientes com diagnóstico de CCL, a redução de FSC no cingulado posterior esquerdo apresentou correlação com atrofia da substância cinzenta, assim como o aumento de FSC no polo temporal superior direito apresentou correlação com o aumento de fluido cerebroespinhal, demonstrando a provável influência do FSC na atrofia encefálica relacionada à DA.

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BACKGROUND: There is a lack of evidence of cognitive involvement in chronic inflammatory demyelinating polyneuropathy (CIDP) and, the reports about the involvement of the brain and central nervous system (CNS) are few and controversial. The Five Digit Test (FDT) evaluates processing speed (PS) and executive functions orally. OBJECTIVE: To evaluate the performance on the FDT of CIDP patients with and without CNS (brain/cerebellum) alterations observed on brain Magnetic Resonance Imaging (MRI) scans. METHODS: The Hospital Anxiety and Depression Scale (HADS, to assess neuropsychiatry symptoms), the Rasch-built Overall Disability Scale (R-ODS; to assess disability), and the FDT (to assess cognition) were applied to 14 CIDP patients and 24 age-matched healthy control subjects. The patients were submitted to routine brain MRI and, according to the results, they were divided into two groups: those with abnormalities on the MRI (CIDPabnl) and those with normal parameters on the MRI (CIDPnl). The FDT data of five CIDPnl patients and nine CIDPabnl subjects were analyzed. Comparisons between the groups were performed for each task of the FDT. RESULTS: We found statistical differences for both groups of CIDP patients in terms of PS, for the patients spent more time performing the PS tasks than the controls. The PS measures were negatively associated with disability scores (reading: r = -0.47; p = 0.003; counting: r = -0.53; p = 0.001). CONCLUSIONS: Our data suggested the presence of PS impairment in CIDP patients. Disability was associated with slow PS.

ANTECEDENTES: Faltam evidências de envolvimento cognitivo na polineuropatia inflamatória desmielinizante crônica (PIDC), e há poucos e controversos estudos que tratam do envolvimento cerebral e do sistema nervoso central (SNC). O Teste dos Cinco Dígitos (Five Digit Test, FDT, em inglês) avalia a velocidade de processamento (VP) e as funções executivas oralmente. OBJETIVO: Avaliar o desempenho no FDT de pacientes com PIDC com e sem alterações no SNC (cérebro/cerebelo) de acordo com o exame de imagem cerebral por ressonância magnética (RM). MéTODOS: Ao todo, 14 pacientes e 24 controles saudáveis pareados por idade responderam a Escala Hospitalar de Ansiedade e Depressão (que avalia sintomas neuropsiquiátricos), a Escala de Incapacidade Geral elaborada pelo método Rasch (que avalia a incapacidade) e o FDT (que avalia a cognição). Os pacientes foram submetidos a RM cerebral e, de acordo com os resultados, divididos em dois grupos: aqueles com anormalidades (PIDCabnl) e aqueles sem alterações (PIDCnl) na RM. Cinco pacientes PIDCnl e nove PIDCabnl tiveram os dados analisados. Comparações entre os grupos foram realizadas para cada parte do FDT. RESULTADOS: Os dois grupos de pacientes foram estatisticamente mais lentos nas tarefas de VP comparados ao grupo controle. As medidas de VP foram negativamente associadas às pontuações de incapacidade (leitura: r = −0,47; p = 0,003; contagem: r = −0,53; p = 0,001). CONCLUSõES: Os dados indicaram a presença de prejuízo na VP em pacientes com PIDC. A incapacidade foi associada à lentidão na VP.

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Abstract Background There is a lack of evidence of cognitive involvement in chronic inflammatory demyelinating polyneuropathy (CIDP) and, the reports about the involvement of the brain and central nervous system (CNS) are few and controversial. The Five Digit Test (FDT) evaluates processing speed (PS) and executive functions orally. Objective To evaluate the performance on the FDT of CIDP patients with and without CNS (brain/cerebellum) alterations observed on brain Magnetic Resonance Imaging (MRI) scans. Methods The Hospital Anxiety and Depression Scale (HADS, to assess neuropsychiatry symptoms), the Rasch-built Overall Disability Scale (R-ODS; to assess disability), and the FDT (to assess cognition) were applied to 14 CIDP patients and 24 age-matched healthy control subjects. The patients were submitted to routine brain MRI and, according to the results, they were divided into two groups: those with abnormalities on the MRI (CIDPabnl) and those with normal parameters on the MRI (CIDPnl). The FDT data of five CIDPnl patients and nine CIDPabnl subjects were analyzed. Comparisons between the groups were performed for each task of the FDT. Results We found statistical differences for both groups of CIDP patients in terms of PS, for the patients spent more time performing the PS tasks than the controls. The PS measures were negatively associated with disability scores (reading: r = −0.47; p = 0.003; counting: r = −0.53; p = 0.001). Conclusions Our data suggested the presence of PS impairment in CIDP patients. Disability was associated with slow PS.

Resumo Antecedentes Faltam evidências de envolvimento cognitivo na polineuropatia inflamatória desmielinizante crônica (PIDC), e há poucos e controversos estudos que tratam do envolvimento cerebral e do sistema nervoso central (SNC). O Teste dos Cinco Dígitos (Five Digit Test, FDT, em inglês) avalia a velocidade de processamento (VP) e as funções executivas oralmente. Objetivo Avaliar o desempenho no FDT de pacientes com PIDC com e sem alterações no SNC (cérebro/cerebelo) de acordo com o exame de imagem cerebral por ressonância magnética (RM). Métodos Ao todo, 14 pacientes e 24 controles saudáveis pareados por idade responderam a Escala Hospitalar de Ansiedade e Depressão (que avalia sintomas neuropsiquiátricos), a Escala de Incapacidade Geral elaborada pelo método Rasch (que avalia a incapacidade) e o FDT (que avalia a cognição). Os pacientes foram submetidos a RM cerebral e, de acordo com os resultados, divididos em dois grupos: aqueles com anormalidades (PIDCabnl) e aqueles sem alterações (PIDCnl) na RM. Cinco pacientes PIDCnl e nove PIDCabnl tiveram os dados analisados. Comparações entre os grupos foram realizadas para cada parte do FDT. Resultados Os dois grupos de pacientes foram estatisticamente mais lentos nas tarefas de VP comparados ao grupo controle. As medidas de VP foram negativamente associadas às pontuações de incapacidade (leitura: r = −0,47; p = 0,003; contagem: r = −0,53; p = 0,001). Conclusões Os dados indicaram a presença de prejuízo na VP em pacientes com PIDC. A incapacidade foi associada à lentidão na VP.

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Background and objectives: understanding the social situation of COVID-19 in poor and less developed countries is still doubtful. Thus, this study aimed to estimate the incidence and lethality by COVID-19, according to the per capita income of the administrative regions of the Federal District (FD). Methods: this is a descriptive ecological study, based on secondary data. Thirty-one administrative regions of the FD were included, and the population consisted of 382,488 individuals. The variables considered were sex, incidence, mortality, lethality, age group, population estimate and education. Results: despite the greater contamination by women, in terms of total mortality, more men died, representing 57.3% of the total deaths in the period. Regarding the influence of the level of education and income on the incidence, it appears that the highest rates of confirmed cases occurred in groups with higher levels of education and income. Despite this higher incidence, it is the group that exhibits the lowest lethality and the third lowest mortality per 100,000 inhabitants. Conclusion: the highest incidence rates were observed in regions with higher per capita income. On the other hand, lethality occurred more incisively in regions with lower purchasing power. In view of this, it is necessary to apply long-term preventive measures in unequal regions.(AU)

Justificativa e objetivos: o entendimento da situação social da COVID-19 em países pobres e menos desenvolvidos ainda é dubitável. Desse modo, o objetivo deste estudo é estimar a incidência e letalidade por COVID-19, de acordo com a renda per capita das regiões administrativas do Distrito Federal (DF). Métodos: trata-se de um estudo ecológico descritivo, baseado em dados secundários. Foram incluídas 31 regiões administrativas do DF, e a população foi composta por 382.488 indivíduos. Consideraram-se como variáveis sexo, incidência, mortalidade, letalidade, faixa etária, estimativa populacional e escolaridade. Resultados: apesar da contaminação maior por parte das mulheres, em termos de mortalidade total, mais homens foram a óbito, representando 57,3% do total de mortos no período. A respeito da influência do grau de escolaridade e da renda na incidência, verifica-se que os maiores índices de casos confirmados aconteceram em grupos com maior nível de escolaridade e de renda. Apesar dessa maior incidência, é o grupo que exibe a menor letalidade e a terceira menor mortalidade por 100.000 habitantes. Conclusão: as mais altas taxas de incidência foram observadas nas regiões com maior renda per capita. Por outro lado, a letalidade ocorreu, de forma mais incisiva, nas regiões de menor poder aquisitivo. Diante disso, é necessário aplicar medidas preventivas de longo prazo em regiões desiguais.(AU)

Justificación y objetivos: la comprensión de la situación social del COVID-19 en los países pobres y menos desarrollados aún es dudosa. Así, el objetivo de este estudio es estimar la incidencia y letalidad por COVID-19, según el ingreso per cápita de las regiones administrativas del Distrito Federal (DF). Métodos: se trata de un estudio ecológico descriptivo, basado en datos secundarios. Se incluyeron 31 regiones administrativas del DF, la población estuvo conformada por 382,488 individuos. Se consideraron como variables el sexo, la incidencia, la mortalidad, la letalidad, el grupo de edad, la población estimada y la escolaridad. Resultados: a pesar de la mayor contaminación por mujeres, en términos de mortalidad total, fallecieron más hombres, representando el 57,3% del total de defunciones en el período. En cuanto a la influencia del nivel de educación e ingresos en la incidencia, parece que las tasas más altas de casos confirmados ocurrieron en grupos con mayores niveles de educación e ingresos. A pesar de esta mayor incidencia, es el grupo que presenta la menor letalidad y la tercera mortalidad más baja por 100.000 habitantes. Conclusión: las tasas de incidencia más altas se observaron en las regiones con mayor ingreso per cápita. Por otro lado, la letalidad se produjo de forma más incisiva en las regiones de menor poder adquisitivo. Ante esto, es necesario aplicar medidas preventivas a largo plazo en regiones desiguales.(AU)

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OBJECTIVE: To evaluate the feasibility of intravoxel incoherent motion (IVIM) in assessing blood-brain barrier (BBB) integrity and microvasculature in tumoral tissue of glioma patients. METHODS: Images from 8 high-grade and 4 low-grade glioma patients were acquired on a 3 T MRI scanner. Acquisition protocol included pre- and post-contrast T1- and T2-weighted imaging, FLAIR, dynamic susceptibility contrast (DSC), and susceptibility-weighted imaging (SWI). In addition, IVIM was acquired with 15 b-values and fitted under the non-negative least square (NNLS) model to output the diffusion (D) and pseudo-diffusion (D*) coefficients, perfusion fraction (f), and f times D* (fD*) maps. RESULTS: IVIM perfusion-related maps were sensitive to (1) blood flow and perfusion alterations within the microvasculature of brain tumors, in agreement with intra-tumoral susceptibility signal (ITSS); (2) enhancing areas of BBB breakdown in agreement with DSC maps as well as areas of BBB abnormality that was not detected on DSC maps; (3) enhancing perfusion changes within edemas; (4) detecting early foci of increased perfusion within low-grade gliomas. CONCLUSION: The results suggest IVIM may be a promising approach to delineate tumor extension and progression in size, and to predict histological grade, which are clinically relevant information that characterize tumors and guide therapeutic decisions in patients with glioma.

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