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1.
Arq Neuropsiquiatr ; 81(11): 980-988, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38035583

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.


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.


Subject(s)
Autoantibodies , Neuromyelitis Optica , Adult , Humans , Child , Female , Adolescent , Young Adult , Middle Aged , Male , Myelin-Oligodendrocyte Glycoprotein , Brazil , Retrospective Studies , Neuromyelitis Optica/drug therapy , Aquaporin 4
2.
Arq. neuropsiquiatr ; 81(11): 980-988, Nov. 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1527889

ABSTRACT

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.

3.
Brain Sci ; 13(5)2023 May 19.
Article in English | MEDLINE | ID: mdl-37239298

ABSTRACT

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.

4.
Diagnostics (Basel) ; 13(4)2023 Feb 20.
Article in English | MEDLINE | ID: mdl-36832287

ABSTRACT

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.

5.
J Clin Endocrinol Metab ; 108(6): 1452-1463, 2023 05 17.
Article in English | MEDLINE | ID: mdl-36504388

ABSTRACT

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.


Subject(s)
ACTH-Secreting Pituitary Adenoma , Adenoma , Pituitary Neoplasms , Humans , Female , Child , Adolescent , Young Adult , Adult , Middle Aged , Aged , Male , Pituitary Neoplasms/genetics , Pituitary Neoplasms/pathology , Adenoma/genetics , Adenoma/pathology , Epigenome , Transcriptome , Retrospective Studies , Cross-Sectional Studies , ACTH-Secreting Pituitary Adenoma/genetics , Adrenocorticotropic Hormone/genetics
6.
Dement. neuropsychol ; 17: e20230004, 2023. tab, graf
Article in English | LILACS | ID: biblio-1514052

ABSTRACT

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.


Subject(s)
Humans
7.
Arq Neuropsiquiatr ; 80(10): 1036-1044, 2022 10.
Article in English | MEDLINE | ID: mdl-36535288

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.


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.


Subject(s)
Polyradiculoneuropathy, Chronic Inflammatory Demyelinating , Humans , Polyradiculoneuropathy, Chronic Inflammatory Demyelinating/complications , Polyradiculoneuropathy, Chronic Inflammatory Demyelinating/diagnosis , Polyradiculoneuropathy, Chronic Inflammatory Demyelinating/pathology , Cross-Sectional Studies , Processing Speed , Central Nervous System , Brain/pathology
8.
Arq. neuropsiquiatr ; 80(10): 1036-1044, Oct. 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1420231

ABSTRACT

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.

9.
Rev. epidemiol. controle infecç ; 12(3): 105-111, jul.-set. 2022. ilus
Article in English, Portuguese | LILACS | ID: biblio-1425661

ABSTRACT

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)


Subject(s)
Humans , Mortality , COVID-19/epidemiology , Per Capita Income
10.
MAGMA ; 35(1): 17-27, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34910266

ABSTRACT

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.


Subject(s)
Blood-Brain Barrier , Glioma , Microvessels , Blood-Brain Barrier/diagnostic imaging , Blood-Brain Barrier/pathology , Blood-Brain Barrier/physiopathology , Diffusion Magnetic Resonance Imaging/methods , Feasibility Studies , Glioma/blood supply , Glioma/diagnostic imaging , Glioma/pathology , Glioma/physiopathology , Humans , Microcirculation , Microvessels/diagnostic imaging , Microvessels/pathology , Motion
11.
Arq Neuropsiquiatr ; 79(8): 705-715, 2021 08.
Article in English | MEDLINE | ID: mdl-34550193

ABSTRACT

BACKGROUND: Meningiomas are the most frequent primary central nervous system (CNS) tumors. Their geographical and ethnic characteristics need to be known, in order to enable rational treatment. OBJECTIVE: To investigate clinical and epidemiological aspects in a series of patients with meningiomas. METHODS: Retrospective analysis on the demographic profile, location and histopathology of 993 patients with meningiomas (768 operated and 225 not operated). RESULTS: Meningiomas represented 43.8% of the primary CNS tumors; 6.8% were multiple tumors (14.7% with neurofibromatosis 2) and 0.6% were radiation-induced tumors. The mean ages were 53.0 and 63.9 years for operated and non-operated patients and the female/male ratios were 3.2:1 and 6.3:1. Diagnosis was made later among females. The peak incidences were in the 6th and 7th decades respectively for operated and non-operated patients. The incidence was low at early ages and higher among patients aged 70+ years. The meningiomas were intracranial in 96.5% and most were WHO grade I (88.9%) and transitional. In the spinal canal (3.5%), they occurred mainly in the dorsal region (all grade I; mostly transitional). The racial distribution was 1.0% in Asian-Brazilians, 87% in Caucasians and 12% in African-Brazilians. 83.4% and 51.6% of the patients were estimated to be recurrence-free at 10 and 20 years, and the mortality rate was 3%. CONCLUSIONS: Most of the demographic data were similar to what has been observed in other western centers. Differences were higher incidence of meningiomas, female and older predominance in non-operated patients, predominance in Caucasian, and higher association with neurofibromatosis 2.


Subject(s)
Meningeal Neoplasms , Meningioma , Neurofibromatosis 2 , Female , Humans , Male , Meningeal Neoplasms/epidemiology , Meningioma/epidemiology , Middle Aged , Neoplasm Recurrence, Local , Retrospective Studies
12.
Arq. neuropsiquiatr ; 79(8): 705-715, Aug. 2021. tab, graf
Article in English | LILACS | ID: biblio-1339228

ABSTRACT

ABSTRACT Background: Meningiomas are the most frequent primary central nervous system (CNS) tumors. Their geographical and ethnic characteristics need to be known, in order to enable rational treatment. Objective: To investigate clinical and epidemiological aspects in a series of patients with meningiomas. Methods: Retrospective analysis on the demographic profile, location and histopathology of 993 patients with meningiomas (768 operated and 225 not operated). Results: Meningiomas represented 43.8% of the primary CNS tumors; 6.8% were multiple tumors (14.7% with neurofibromatosis 2) and 0.6% were radiation-induced tumors. The mean ages were 53.0 and 63.9 years for operated and non-operated patients and the female/male ratios were 3.2:1 and 6.3:1. Diagnosis was made later among females. The peak incidences were in the 6th and 7th decades respectively for operated and non-operated patients. The incidence was low at early ages and higher among patients aged 70+ years. The meningiomas were intracranial in 96.5% and most were WHO grade I (88.9%) and transitional. In the spinal canal (3.5%), they occurred mainly in the dorsal region (all grade I; mostly transitional). The racial distribution was 1.0% in Asian-Brazilians, 87% in Caucasians and 12% in African-Brazilians. 83.4% and 51.6% of the patients were estimated to be recurrence-free at 10 and 20 years, and the mortality rate was 3%. Conclusions: Most of the demographic data were similar to what has been observed in other western centers. Differences were higher incidence of meningiomas, female and older predominance in non-operated patients, predominance in Caucasian, and higher association with neurofibromatosis 2.


RESUMO Antecedentes: Meningiomas são os tumores mais frequentes do sistema nervoso central (SNC). Suas características étnicas e geográficas precisam ser conhecidas para o seu tratamento racional. Objetivo: Investigar aspectos clínicos e epidemiológicos de uma série de pacientes com meningiomas. Métodos: Análise retrospectiva demográfica de 993 pacientes com meningiomas (768 operados e 225 tratados conservadoramente) Resultados: Meningiomas constituíram 43.8% dos tumores primários do SNC. 0.8% deles eram múltiplos (14,7% com neurofibromatose 2) e 0,6% eram radioinduzidos. A idade média e o índice mulheres/homens foram respectivamente 53,0 e 63,9 anos e 3.2:1 e 6.3:1 para pacientes operados e não operados. O diagnóstico foi mais tardio em mulheres. Ocorreram picos de incidências na 6ª e na 7ª décadas respectivamente para pacientes operados e não operados. A incidência foi menor na infância e maior após 70 anos. Meningiomas predominaram no crânio (96.5%), a maioria grau I da OMS, subtipo transicional. Do total, 3.5% ocorreram no canal raquídeo, principalmente na região torácica, todos grau I, a maioria transicional. Em relação à distribuição racial, 1.0% dos meningiomas ocorreu em amarelos, 87% em brancos e 12% em negros. As taxas de sobrevida sem recorrência foram 83.4% e 51.6% em 10 e 20 anos e a mortalidade operatória foi 3%. Conclusões: A maioria dos dados demográficos observados foi similar aos de outros centros ocidentais. As diferenças observadas foram maior incidência, predominância em mulheres e idosos nos pacientes não operados e em caucasianos, e maior associação com neurofibromatose 2.


Subject(s)
Humans , Male , Female , Neurofibromatosis 2 , Meningeal Neoplasms/epidemiology , Meningioma/epidemiology , Retrospective Studies , Middle Aged , Neoplasm Recurrence, Local
13.
JAMA Netw Open ; 4(5): e219878, 2021 05 03.
Article in English | MEDLINE | ID: mdl-33983398

ABSTRACT

Importance: The Zika virus infects progenitor neuron cells, disrupts cerebral development, and, in mice, drives hypothalamic defects. Patients with microcephaly caused by congenital Zika infection present with midline cerebral defects, which may result in hypopituitarism. Objective: To analyze postnatal growth and the presence of clinical and biochemical features associated with hypopituitarism in children with congenital Zika infections. Design, Setting, and Participants: In this prospective cohort study at 2 public referral hospitals in Bahia, Brazil, specializing in the treatment of congenital Zika infection, clinical data and growth parameters of 65 patients with the infection were evaluated. Data were analyzed from April 2017 through July 2018. Exposure: Congenital Zika infection. Main Outcomes and Measures: Length, weight, and head circumference were measured at birth and during follow up (ie, at 27 months of life) for each patient. Basal levels of free thyroxine, thyrotropin, cortisol, corticotropin, prolactin, insulin-like growth factor 1, insulin-like growth factor binding protein 3, urine and plasma osmolality, electrolytes, glucose, and insulin were evaluated at the age of 26 months to 28 months. All patients underwent central nervous system computed tomography scans and ophthalmic and otoacoustic evaluations at the time of this investigation or had done so previously. Results: Among 65 patients (38 [58.4%] male; median [interquartile range] age at enrollment, 27 [26-28] months), 61 patients presented with severe brain defects (93.8%), including corpus callosum agenesis or hypoplasia (ie, midline brain defects; 25 patients [38.5%]) and optic nerve atrophy (38 patients [58.5%]). Most patients presented with severe neurodevelopmental delay (62 of 64 patients [96.9%]). Past or present clinical signs of hypopituitarism were rare, occurring in 3 patients (4.6%). Severe microcephaly, compared with mild or moderate microcephaly, was associated with a shorter length by median (interquartile range) z score at birth (-1.9 [-2.5 to -1.0] vs -0.3 [-1.0 to 0]; P < .001), but this difference did not persist at 27 months (-1.6 [-2.3 to -0.3] vs -2.9 [-4.0 to -1.2]; P = .06). Growth hormone deficiency or hypothyroidism were not observed in any patients, and glucose and insulin levels were within reference ranges for all patients. Low cortisol levels (ie, below 3.9 µg/dL) were observed in 4 patients (6.2%). These 4 patients presented with low (ie, below 7.2 pg/mL) or inappropriately low (ie, below 30 pg/mL) corticotropin levels. Low corticotropin levels (ie, below 7.2 pg/mL) were observed in 6 patients (9.2%). Diabetes insipidus was evaluated in 21 patients; it was confirmed in 1 patient (4.8%) and suggested in 3 patients (14.3%). Conclusions and Relevance: This study found that congenital Zika infection with microcephaly was associated with midline brain defects and optic nerve atrophy. Children with congenital Zika infections presented with prenatal growth impairments with a lack of postnatal catch-up, as shown by persistent short length from birth until 27 months; these impairments were not associated with growth hormone deficiency. Patients also presented with severe developmental delay that was not associated with hypothyroidism, while central adrenal insufficiency and diabetes insipidus occurred in some patients.


Subject(s)
Hypopituitarism/virology , Microcephaly/virology , Zika Virus Infection/complications , Brazil , Child, Preschool , Female , Humans , Hypopituitarism/diagnosis , Hypopituitarism/etiology , Hypopituitarism/pathology , Male , Microcephaly/diagnostic imaging , Microcephaly/etiology , Microcephaly/pathology , Neuroimaging , Tomography, X-Ray Computed , Zika Virus Infection/diagnostic imaging , Zika Virus Infection/pathology
14.
Neuroimage Clin ; 28: 102463, 2020.
Article in English | MEDLINE | ID: mdl-33395959

ABSTRACT

OBJECTIVE: Temporal lobe epilepsy patients (TLE) often present with hippocampal atrophy, increased T2 relaxation, and reduced magnetization transfer ratio (MTR) in magnetic resonance images (MRI). The histological correlates of the reduced hippocampal MTR are so far unknown. Since MTR is dependent on the tissue's macromolecules, our aim was to evaluate the correlations between cellular populations, extracellular matrix molecules and the MTR in TLE patients. METHODS: Patients with TLE (n = 26) and voluntaries (=20) were scanned in a 3 Tesla MRI scanner, and MTR images were calculated from 3DT1 sequences with magnetization pulse on resonance. Immunohistochemistry for neurons, reactive astrocytes, activated microglia, and extracellular matrix chondroitin sulfate were performed in formalin fixed, paraffin embedded tissues of TLE and autopsy controls (n = 10). Results were considered significant with adjusted p < 0.05. RESULTS: Compared to the respective controls, TLE patients had reduced hippocampal MTR, increased reactive astrocytes and activated microglia, increased extracellular chondroitin sulfate, and reduced neuron density, compares to controls. MTR correlated positively with neuron density in CA3 and with chondroitin sulfate in CA3 and CA1. Multiple linear regressions reinforced the correlations between chondroitin sulfate and MTR. SIGNIFICANCE: Our data indicate that extracellular matrix molecules are the most significant histological correlates of magnetization transfer ratio in the hippocampus of TLE patients.


Subject(s)
Drug Resistant Epilepsy , Epilepsy, Temporal Lobe , Pharmaceutical Preparations , Drug Resistant Epilepsy/diagnostic imaging , Epilepsy, Temporal Lobe/diagnostic imaging , Hippocampus/diagnostic imaging , Humans , Magnetic Resonance Imaging , Temporal Lobe
15.
Mult Scler ; 26(8): 945-954, 2020 07.
Article in English | MEDLINE | ID: mdl-31124748

ABSTRACT

OBJECTIVE: We aimed to evaluate magnetic resonance imaging (MRI) previously used criteria (Matthews's criteria, MC) for differentiating multiple sclerosis (MS) from neuromyelitis optica spectrum disorders (NMOSD) in Caucasian and non-Caucasian populations (Argentina, Brazil and Venezuela) with positive (P-NMOSD), negative (N-NMOSD), and unknown (U-NMOSD) aquaporin-4 antibody serostatus at disease onset and to assess the added diagnostic value of spinal cord MRI in these populations. METHODS: We reviewed medical records, and MRIs were assessed by two blinded evaluators and were scored using MC. Short-segment transverse myelitis (STM) was added as a new criterion. MC sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were determined. RESULTS: We included 282 patients (MS = 188 and NMOSD = 94). MC applied to the entire cohort showed 97.8% sensitivity, 82.9% specificity, 92.0% PPV, and 95.1% NPV for differentiating MS from NMOSD. A subanalysis applied only to non-Caucasian (MS = 89 and NMOSD = 47) showed 100% sensitivity, 80.8% specificity, 90.8% PPV, and 100% NPV. Similar sensitivity, specificity, PPV, and NPV of MC for MS versus P-NMOSD (n = 55), N-NMOSD (n = 28), and U-NMOSD (n = 21) were observed. CONCLUSION: MC distinguished MS from NMOSD of all serostatus in a Latin American cohort that included non-Caucasian populations. Addition of STM to MC did not raise the accuracy significantly.


Subject(s)
Aquaporin 4/immunology , Autoantibodies/blood , Brain/diagnostic imaging , Magnetic Resonance Imaging/standards , Multiple Sclerosis/diagnostic imaging , Neuromyelitis Optica/diagnostic imaging , Practice Guidelines as Topic , Spinal Cord/diagnostic imaging , Adult , Argentina , Brain/pathology , Brazil , Diagnosis, Differential , Female , Humans , Male , Middle Aged , Multiple Sclerosis/blood , Multiple Sclerosis/pathology , Neuromyelitis Optica/blood , Neuromyelitis Optica/pathology , Predictive Value of Tests , Retrospective Studies , Sensitivity and Specificity , Single-Blind Method , Spinal Cord/pathology , Venezuela , Young Adult
16.
Res. Biomed. Eng. (Online) ; 34(2): 138-146, Apr.-June 2018. tab, graf
Article in English | LILACS | ID: biblio-956288

ABSTRACT

Abstract Introduction Multiple Sclerosis (MS) is a neurodegenerative disease characterized by inflammatory demyelination in the central nervous system. Quantitative Magnetic Resonance Imaging (qMRI) enables a detailed characterization of brain tissue, but generates a large number of numerical results. In this study, we elucidated the main qMRI techniques and the brain regions that allow the identification of MS patients from neuroimaging data and pattern recognition techniques. Methods The data came from the combination of computational tools of image processing and neuroimaging acquired in a 3 Tesla scanner using different techniques: Diffusion, T2 Relaxometry, Magnetization Transfer Ratio (MTR) and Structural Morphometry. Data from 126 brain regions of 203 healthy individuals and 124 MS patients were separated into two groups and processed in a data-mining program using the k-nearest-neighbor (KNN) algorithm. Results The most relevant anatomical structures in the classification procedure were: corpus callosum, precuneus, left cerebellum and fusiform. Among the quantitative techniques the most relevant was the MTR, being indicated for longitudinal studies of this disease. KNN with 5 neighbors and pre-selected attributes had a better performance with an area under the ROC curve (97.3%) and accuracy (95.7%). A restricted classification considering only brain regions previously reported in the literature as affected by MS brought slightly lower scores, area: 97.1% and accuracy: 93.2%. Conclusion The use of standard recognition techniques from quantitative neuroimaging techniques has confirmed that the white matter of the brain is the most affected tissue by MS following a global pattern with greater involvement of the left hemisphere.

17.
Radiol. bras ; 51(2): 71-75, Mar.-Apr. 2018. tab, graf
Article in English | LILACS | ID: biblio-956240

ABSTRACT

Abstract Objective: To examine the potential of two magnetic resonance imaging (MRI) techniques-dynamic contrast enhancement (DCE) and diffusion-weighted imaging (DWI)-for the detection of malignant cervical lymph nodes. Materials and Methods: Using DCE and DWI, we evaluated 33 cervical lymph nodes. For the DCE technique, the maximum relative enhancement, relative enhancement, time to peak enhancement, wash-in rate, wash-out rate, brevity of enhancement, and area under the curve were calculated from a semi-quantitative analysis. For the DWI technique, apparent diffusion coefficients (ADCs) were acquired in the region of interest of each lymph node. Cystic or necrotic parts were excluded. All patients underwent neck dissection or node biopsy. Imaging results were correlated with the histopathological findings. None of the patients underwent neoadjuvant treatment before neck dissection. Results: Relative enhancement, maximum relative enhancement, and the wash-in rate were significantly higher in malignant lymph nodes than in benign lymph nodes (p < 0.009; p < 0.05; and p < 0.03, respectively). The time to peak enhancement was significantly shorter in the malignant lymph nodes (p < 0.02). In the multivariate analysis, the variables identified as being the most capable of distinguishing between benign and malignant lymph nodes were time to peak enhancement (sensitivity, 73.7%; specificity, 69.2%) and relative enhancement (sensitivity, 89.2%; specificity, 69.2%). Conclusion: Although DCE was able to differentiate between benign and malignant lymph nodes, there is still no consensus regarding the use of a semi-quantitative analysis, which is difficult to apply in a clinical setting. Low ADCs can predict metastatic disease, although inflammatory processes might lead to false-positive results.


Resumo Objetivo: Examinar o potencial das imagens de contraste dinâmico (DCE-MRI) e difusão (DW-MRI) em ressonância magnética na detecção de linfonodos cervicais malignos. Materiais e Métodos: Foram realizadas DCE-MRI e DW-MRI em 33 linfonodos cervicais. Os valores de realce relativo máximo, realce relativo, tempo de pico, taxa de realce e lavagem, brevidade do realce e área sob a curva foram avaliados pela análise semiquantitativa (DCE-MRI). Os coeficientes de difusão aparente na DW-MRI foram obtidos na área de interesse. Foram excluídas partes císticas ou necróticas dos nódulos. Todos os pacientes foram submetidos a dissecção cervical ou a biópsia. Os resultados de imagem foram correlacionados com os achados patológicos. Nenhum paciente foi submetido a tratamento neoadjuvante antes da dissecção do pescoço. Resultados: Realce relativo, realce relativo máximo e taxa de realce aumentaram nos nódulos malignos (p < 0,009, p < 0,05 e p < 0,03, respectivamente). O tempo de pico foi reduzido nos nódulos malignos (p < 0,02). A análise multivariada identificou tempo de pico (sensibilidade, 73,7%; especificidade, 69,2%) e realce relativo (sensibilidade, 89,2%; especificidade, 69,2%) como variáveis capazes de distinguir os nódulos benignos e malignos. Conclusão: Embora o DCE-MRI possa diferenciar os nódulos benignos e malignos, ainda não há consenso sobre a técnica de análise semiquantitativa, em razão de dificuldade de aplicação clínica. Valores baixos do coeficiente de difusão aparente podem predizer nódulo metastático, mas devem-se considerar também resultados falso-positivos, provavelmente secundários ao processo inflamatório.

19.
Radiol. bras ; 50(5): 323-327, Sept.-Oct. 2017. graf
Article in English | LILACS | ID: biblio-896117

ABSTRACT

Abstract Perineural tumor spread refers to the migration of tumor cells along nerve tissues. It worsens the prognosis, increases the recurrence rate, and diminishes 5-year survival by up to 30%. It is an important finding on imaging tests employed in the staging of patients with head and neck cancers, because it cannot be assessed by the surgeon alone. Nevertheless, it is frequently overlooked. In this study, we reviewed the literature regarding the imaging and pathophysiological aspects of this type of dissemination. We also analyzed ten imaging tests, obtained from a teaching hospital in Brazil, in which there were radiological signs of perineural tumor spread.


Resumo Disseminação perineural de tumores refere-se à extensão de células tumorais ao longo do tecido dos nervos. Acarreta um pior prognóstico, aumenta a taxa de recorrência e diminui a expectativa de vida em cinco anos em até 30%. É um achado importante em exames de imagem quando se estadia pacientes com cânceres de cabeça e pescoço, já que não pode ser avaliado somente pelo cirurgião. Todavia, é uma alteração que frequentemente passa despercebida. No presente estudo, revisamos trabalhos científicos da literatura médica sobre os achados de imagem e os aspectos fisiopatológicos desse tipo de disseminação e analisamos 10 exames de imagem com sinais radiológicos de disseminação perineural oriundos de um hospital-escola brasileiro.

20.
Res. Biomed. Eng. (Online) ; 33(3): 247-258, Sept. 2017. tab, graf
Article in English | LILACS | ID: biblio-896187

ABSTRACT

Abstract Introduction: Diffusion tensor imaging (DTI) is an important medical imaging modality that has been useful to the study of microstructural changes in neurological diseases. However, the image noise level is a major practical limitation, in which one simple solution could be the average signal from a sequential acquisition. Nevertheless, this approach is time-consuming and is not often applied in the clinical routine. In this study, we aim to evaluate the anisotropic anomalous diffusion (AAD) filter in order to improve the general image quality of DTI. Methods A group of 20 healthy subjects with DTI data acquired (3T MR scanner) with different numbers of averages (N=1,2,4,6,8, and 16), where they were submitted to 2-D AAD and conventional anisotropic diffusion filters. The Relative Mean Error (RME), Structural Similarity Index (SSIM), Coefficient of Variation (CV) and tractography reconstruction were evaluated on Fractional Anisotropy (FA) and Apparent Diffusion Coefficient (ADC) maps. Results The results point to an improvement of up to 30% of CV, RME, and SSIM for the AAD filter, while up to 14% was found for the conventional AD filter (p<0.05). The tractography revealed a better estimative in fiber counting, where the AAD filter resulted in less FA variability. Furthermore, the AAD filter showed a quality improvement similar to a higher average approach, i.e. achieving an image quality equivalent to what was seen in two additional acquisitions. Conclusions In general, the AAD filter showed robustness in noise attenuation and global image quality improvement even in DTI images with high noise level.

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