Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.434
Filtrar
1.
Cereb Cortex ; 34(5)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38741269

RESUMO

The basal nuclei are important during infancy because of the significant development of motor skills. The main aim of this study was to evaluate the shape differences of the lentiform nucleus between different age and gender groups. A total of 126 children's axial magnetic resonance image series were included in the presented study. These images were grouped between 1 and 5 yr old. Right and left lentiform nuclei are marked with selected landmarks using TPSDIG v2.04. Statistical shape analyses were examined by a Generalized Procrustes Analysis. Our results showed that there was no statistically significant difference in lentiform nucleus shape between genders. However, there was a difference between the shapes of the right and left lentiform nuclei between the 1-yr and 5-yr age groups. These results demonstrated the shape changes in the lentiform nucleus during the first 5 yr of life. Further clinical studies based on our results may be used to gather more detailed information about movement disorders and neuronal development.


Assuntos
Imageamento por Ressonância Magnética , Humanos , Masculino , Feminino , Pré-Escolar , Lactente , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos , Envelhecimento/fisiologia , Envelhecimento/patologia , Gânglios da Base/diagnóstico por imagem
2.
Int J Dev Neurosci ; 84(3): 163-176, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38488315

RESUMO

INTRODUCTION: Recent research indicates that some brain structures show alterations in conditions such as Autism Spectrum Disorder (ASD). Among them, are the basal ganglia that are involved in motor, cognitive and behavioral neural circuits. OBJECTIVE: Review the literature that describes possible volumetric alterations in the basal ganglia of individuals with ASD and the impacts that these changes have on the severity of the condition. METHODOLOGY: This systematic review was registered in the design and reported according to the PRISMA Items and registered in PROSPERO (CRD42023394787). The study analyzed data from published clinical, case-contemplate, and cohort trials. The following databases were consulted: PubMed, Embase, Scopus, and Cochrane Central Register of Controlled Trials, using the Medical Subject Titles (MeSH) "Autism Spectrum Disorder" and "Basal Ganglia". The last search was carried out on February 28, 2023. RESULTS: Thirty-five eligible articles were collected, analyzed, and grouped according to the levels of alterations. CONCLUSION: The present study showed important volumetric alterations in the basal ganglia in ASD. However, the examined studies have methodological weaknesses that do not allow generalization and correlation with ASD manifestations.


Assuntos
Transtorno do Espectro Autista , Gânglios da Base , Humanos , Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/patologia , Transtorno do Espectro Autista/fisiopatologia , Gânglios da Base/patologia , Gânglios da Base/diagnóstico por imagem
3.
Ann Neurol ; 95(5): 849-857, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38366778

RESUMO

OBJECTIVE: One proposed mechanism of disease progression in Parkinson's disease includes the interplay of endogenous dopamine toxicity and mitochondrial dysfunction. However, the in-vivo effects of exogenous dopamine administration on cerebral bioenergetics are unknown. METHODS: We performed a double-blinded, cross-over, placebo-controlled trial. Participants received either 200/50 mg levodopa/benserazide or a placebo and vice versa on the second study visit. Clinical assessments and multimodal neuroimaging were performed, including 31phosphorus magnetic resonance spectroscopy of the basal ganglia and the midbrain. RESULTS: In total, 20 (6 female) patients with Parkinson's disease and 22 sex- and age-matched healthy controls (10 female) were enrolled. Treatment with levodopa/benserazide but not with placebo resulted in a substantial reduction of high-energy phosphorus-containing metabolites in the basal ganglia (patients with Parkinson's disease: -40%; healthy controls: -39%) but not in the midbrain. There were no differences in high-energy phosphorus-containing metabolites for patients with Parkinson's disease compared to healthy controls in the OFF state and treatment response. INTERPRETATION: Exogenously administered levodopa/benserazide strongly interferes with basal ganglia high-energy phosphorus-containing metabolite levels in both groups. The lack of effects on midbrain levels suggests that the observed changes are limited to the site of dopamine action. ANN NEUROL 2024;95:849-857.


Assuntos
Gânglios da Base , Benserazida , Estudos Cross-Over , Metabolismo Energético , Levodopa , Doença de Parkinson , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Gânglios da Base/metabolismo , Gânglios da Base/efeitos dos fármacos , Gânglios da Base/diagnóstico por imagem , Idoso , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Doença de Parkinson/diagnóstico por imagem , Benserazida/farmacologia , Método Duplo-Cego , Metabolismo Energético/efeitos dos fármacos , Antiparkinsonianos , Combinação de Medicamentos , Espectroscopia de Ressonância Magnética/métodos
4.
Artigo em Inglês | MEDLINE | ID: mdl-38325744

RESUMO

Different lines of evidence indicate that the structure and physiology of the basal ganglia and the thalamus is disturbed in schizophrenia. However, it is unknown whether the volume and shape of these subcortical structures are affected in schizophrenia with auditory hallucinations (AH), a core positive symptom of the disorder. We took structural MRI from 63 patients with schizophrenia, including 36 patients with AH and 27 patients who had never experienced AH (NAH), and 51 matched healthy controls. We extracted volumes for the left and right thalamus, globus pallidus, putamen, caudate and nucleus accumbens. Shape analysis was also carried out. When comparing to controls, the volume of the right globus pallidus, thalamus, and putamen, was only affected in AH patients. The volume of the left putamen was also increased in individuals with AH, whereas the left globus pallidus was affected in both groups of patients. The shapes of right and left putamen and thalamus were also affected in both groups. The shape of the left globus pallidus was only altered in patients lacking AH, both in comparison to controls and to cases with AH. Lastly, the general PANSS subscale was correlated with the volume of the right thalamus, and the right and left putamen, in patients with AH. We have found volume and shape alterations of many basal ganglia and thalamus in patients with and without AH, suggesting in some cases a possible relationship between this positive symptom and these morphometric alterations.


Assuntos
Esquizofrenia , Humanos , Esquizofrenia/complicações , Esquizofrenia/diagnóstico por imagem , Gânglios da Base/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Putamen/diagnóstico por imagem , Alucinações/diagnóstico por imagem , Imageamento por Ressonância Magnética
6.
Mov Disord Clin Pract ; 11(5): 550-555, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38404049

RESUMO

BACKGROUND: X-linked dystonia-parkinsonism (XDP) is a rare movement disorder characterized by profound neurodegeneration in the basal ganglia. The molecular consequences and the bioenergetic state of affected individuals remain largely unexplored. OBJECTIVES: To investigate the bioenergetic state in male patients with XDP and female carriers using 31phosphorus magnetic resonance spectroscopy imaging and to correlate these findings with clinical manifestations. METHODS: We examined the levels of high-energy phosphorus-containing metabolites (HEP) in the basal ganglia and cerebellum of five male patients with XDP, 10 asymptomatic female heterozygous carriers, and 10 SVA-insertion-free controls. RESULTS: HEP levels were reduced in the basal ganglia of patients with XDP (PwXDP) compared to controls, but increased in the cerebellum of both male patients and female carriers. CONCLUSIONS: Our findings suggest a potential compensatory mechanism in the cerebellum of female carriers regardless of sex. Our study highlights alterations in HEP levels in PwXDP patients and female carriers.


Assuntos
Gânglios da Base , Cerebelo , Distúrbios Distônicos , Doenças Genéticas Ligadas ao Cromossomo X , Heterozigoto , Humanos , Feminino , Masculino , Distúrbios Distônicos/genética , Distúrbios Distônicos/metabolismo , Distúrbios Distônicos/diagnóstico por imagem , Distúrbios Distônicos/fisiopatologia , Distúrbios Distônicos/patologia , Doenças Genéticas Ligadas ao Cromossomo X/genética , Doenças Genéticas Ligadas ao Cromossomo X/metabolismo , Doenças Genéticas Ligadas ao Cromossomo X/fisiopatologia , Doenças Genéticas Ligadas ao Cromossomo X/patologia , Adulto , Pessoa de Meia-Idade , Gânglios da Base/metabolismo , Gânglios da Base/diagnóstico por imagem , Cerebelo/metabolismo , Cerebelo/diagnóstico por imagem , Cerebelo/patologia , Espectroscopia de Ressonância Magnética , Adulto Jovem , Metabolismo Energético
7.
Neuroimage Clin ; 41: 103568, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38277807

RESUMO

INTRODUCTION: Neonatal arterial ischemic stroke (NAIS) is a common model to study the impact of a unilateral early brain insult on developmental brain plasticity and the appearance of long-term outcomes. Motor difficulties that may arise are typically related to poor function of the affected (contra-lesioned) hand, but surprisingly also of the ipsilesional hand. Although many longitudinal studies after NAIS have shown that predicting the occurrence of gross motor difficulties is easier, accurately predicting hand motor function (for both hands) from morphometric MRI remains complicated. The hypothesis of an association between the structural organization of the basal ganglia (BG) and thalamus with hand motor function seems intuitive given their key role in sensorimotor function. Neuroimaging studies have frequently investigated these structures to evaluate the correlation between their volumes and motor function following early brain injury. However, the results have been controversial. We hypothesize the involvement of other structural parameters. METHOD: The study involves 35 children (mean age 7.3 years, SD 0.4) with middle cerebral artery NAIS who underwent a structural T1-weighted 3D MRI and clinical examination to assess manual dexterity using the Box and Blocks Test (BBT). Graphs are used to represent high-level structural information of the BG and thalami (volumes, elongations, distances) measured from the MRI. A graph neural network (GNN) is proposed to predict children's hand motor function through a graph regression. To reduce the impact of external factors on motor function (such as behavior and cognition), we calculate a BBT score ratio for each child and hand. RESULTS: The results indicate a significant correlation between the score ratios predicted by our method and the actual score ratios of both hands (p < 0.05), together with a relatively high accuracy of prediction (mean L1 distance < 0.03). The structural information seems to have a different influence on each hand's motor function. The affected hand's motor function is more correlated with the volume, while the 'unaffected' hand function is more correlated with the elongation of the structures. Experiments emphasize the importance of considering the whole macrostructural organization of the basal ganglia and thalami networks, rather than the volume alone, to predict hand motor function. CONCLUSION: There is a significant correlation between the structural characteristics of the basal ganglia/thalami and motor function in both hands. These results support the use of MRI macrostructural features of the basal ganglia and thalamus as an early biomarker for predicting motor function in both hands after early brain injury.


Assuntos
Lesões Encefálicas , AVC Isquêmico , Acidente Vascular Cerebral , Criança , Recém-Nascido , Humanos , Encéfalo , Imageamento por Ressonância Magnética/métodos , Mãos , Gânglios da Base/diagnóstico por imagem , Lesões Encefálicas/complicações , Tálamo/diagnóstico por imagem
8.
Mol Autism ; 15(1): 6, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-38254158

RESUMO

BACKGROUND: Restricted repetitive behavior (RRB) is one of two behavioral domains required for the diagnosis of autism spectrum disorder (ASD). Neuroimaging is widely used to study brain alterations associated with ASD and the domain of social and communication deficits, but there has been less work regarding brain alterations linked to RRB. METHODS: We utilized neuroimaging data from the National Institute of Mental Health Data Archive to assess basal ganglia and cerebellum structure in a cohort of children and adolescents with ASD compared to typically developing (TD) controls. We evaluated regional gray matter volumes from T1-weighted anatomical scans and assessed diffusion-weighted scans to quantify white matter microstructure with free-water imaging. We also investigated the interaction of biological sex and ASD diagnosis on these measures, and their correlation with clinical scales of RRB. RESULTS: Individuals with ASD had significantly lower free-water corrected fractional anisotropy (FAT) and higher free-water (FW) in cortico-basal ganglia white matter tracts. These microstructural differences did not interact with biological sex. Moreover, both FAT and FW in basal ganglia white matter tracts significantly correlated with measures of RRB. In contrast, we found no significant difference in basal ganglia or cerebellar gray matter volumes. LIMITATIONS: The basal ganglia and cerebellar regions in this study were selected due to their hypothesized relevance to RRB. Differences between ASD and TD individuals that may occur outside the basal ganglia and cerebellum, and their potential relationship to RRB, were not evaluated. CONCLUSIONS: These new findings demonstrate that cortico-basal ganglia white matter microstructure is altered in ASD and linked to RRB. FW in cortico-basal ganglia and intra-basal ganglia white matter was more sensitive to group differences in ASD, whereas cortico-basal ganglia FAT was more closely linked to RRB. In contrast, basal ganglia and cerebellar volumes did not differ in ASD. There was no interaction between ASD diagnosis and sex-related differences in brain structure. Future diffusion imaging investigations in ASD may benefit from free-water estimation and correction in order to better understand how white matter is affected in ASD, and how such measures are linked to RRB.


Assuntos
Transtorno do Espectro Autista , Substância Branca , Estados Unidos , Adolescente , Criança , Humanos , Substância Branca/diagnóstico por imagem , Transtorno do Espectro Autista/diagnóstico por imagem , Gânglios da Base/diagnóstico por imagem , Encéfalo , Água
9.
J Integr Neurosci ; 23(1): 5, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38287852

RESUMO

Post-traumatic striatocapsular infarction (SCI) due to lenticulostriate artery (LSA) damage is rare. Most cases reported are in children. We discuss the pathogenesis and differential diagnosis of this kind of SCI after trauma in adult patients. The most common etiology of non-traumatic SCI are an embolism from the proximal artery, cardiogenic embolism, and atherosclerotic plaque in the proximal middle cerebral artery (MCA). However, injury of the LSA after trauma may lead to hemorrhagic infarction in the basal ganglia (BG). Post-traumatic SCI due to LSA damage might be associated with hemorrhage in the BG. The main locations of these lesions are the distal perfusion area of the LSA, similar to SCI due to intracranial atherosclerotic disease affecting the MCA. Vessel wall imaging, magnetic resonance angiography, and ultrahigh-resolution computed tomography can be used for differentiating the injury mechanism in SCI following a traumatic event.


Assuntos
Embolia , Artéria Cerebral Média , Adulto , Criança , Humanos , Infarto Cerebral/patologia , Gânglios da Base/diagnóstico por imagem , Infarto/complicações , Infarto/patologia , Embolia/complicações , Embolia/patologia
10.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38059685

RESUMO

In the perinatal period, reward and cognitive systems begin trajectories, influencing later psychiatric risk. The basal ganglia is important for reward and cognitive processing but early development has not been fully characterized. To assess age-related development, we used a measure of basal ganglia physiology, specifically brain tissue iron, obtained from nT2* signal in resting-state functional magnetic resonance imaging (rsfMRI), associated with dopaminergic processing. We used data from the Developing Human Connectome Project (n = 464) to assess how moving from the prenatal to the postnatal environment affects rsfMRI nT2*, modeling gestational and postnatal age separately for basal ganglia subregions in linear models. We did not find associations with tissue iron and gestational age [range: 24.29-42.29] but found positive associations with postnatal age [range:0-17.14] in the pallidum and putamen, but not the caudate. We tested if there was an interaction between preterm birth and postnatal age, finding early preterm infants (GA < 35 wk) had higher iron levels and changed less over time. To assess multivariate change, we used support vector regression to predict age from voxel-wise-nT2* maps. We could predict postnatal but not gestational age when maps were residualized for the other age term. This provides evidence subregions differentially change with postnatal experience and preterm birth may disrupt trajectories.


Assuntos
Recém-Nascido Prematuro , Nascimento Prematuro , Lactente , Feminino , Recém-Nascido , Humanos , Imageamento por Ressonância Magnética , Nascimento Prematuro/patologia , Ferro , Gânglios da Base/diagnóstico por imagem , Encéfalo/diagnóstico por imagem
11.
Artigo em Inglês | MEDLINE | ID: mdl-37952692

RESUMO

BACKGROUND: The basal ganglia are strongly connected to the primary motor cortex (M1) and play a crucial role in movement control. Interestingly, several disorders showing abnormal neurotransmitter levels in basal ganglia also present concomitant anomalies in intracortical function within M1. OBJECTIVE/HYPOTHESIS: The main aim of this study was to clarify the relationship between neurotransmitter content in the basal ganglia and intracortical function at M1 in healthy individuals. We hypothesized that neurotransmitter content of the basal ganglia would be significant predictors of M1 intracortical function. METHODS: We combined magnetic resonance spectroscopy (MRS) and transcranial magnetic stimulation (TMS) to test this hypothesis in 20 healthy adults. An extensive TMS battery probing common measures of intracortical, and corticospinal excitability was administered, and GABA and glutamate-glutamine levels were assessed from voxels placed over the basal ganglia and the occipital cortex (control region). RESULTS: Regression models using metabolite concentration as predictor and TMS metrics as outcome measures showed that glutamate level in the basal ganglia significantly predicted short interval intracortical inhibition (SICI) and intracortical facilitation (ICF), while GABA content did not. No model using metabolite measures from the occipital control voxel was significant. CONCLUSIONS: Taken together, these results converge with those obtained in clinical populations and suggest that intracortical circuits in human M1 are associated with the neurotransmitter content of connected but distal subcortical structures crucial for motor function.


Assuntos
Córtex Motor , Adulto , Humanos , Córtex Motor/diagnóstico por imagem , Córtex Motor/fisiologia , Inibição Neural/fisiologia , Potencial Evocado Motor/fisiologia , Ácido Glutâmico/metabolismo , Estimulação Magnética Transcraniana/métodos , Gânglios da Base/diagnóstico por imagem , Ácido gama-Aminobutírico/metabolismo
12.
Brain Imaging Behav ; 18(1): 57-65, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37855955

RESUMO

Perivascular spaces (PVS), fluid-filled compartments surrounding brain vasculature, are an essential component of the glymphatic system responsible for transport of waste and nutrients. Glymphatic system impairment may underlie cognitive deficits in Parkinson's disease (PD). Studies have focused on the role of basal ganglia PVS with cognition in PD, but the role of white matter PVS is unknown. This study examined the relationship of white matter and basal ganglia PVS with domain-specific and global cognition in individuals with PD. Fifty individuals with PD underwent 3T T1w magnetic resonance imaging (MRI) to determine PVS volume fraction, defined as PVS volume normalized to total regional volume, within (i) centrum semiovale, (ii) prefrontal white matter (medial orbitofrontal, rostral middle frontal, superior frontal), and (iii) basal ganglia. A neuropsychological battery included assessment of global cognitive function (Montreal Cognitive Assessment, and global cognitive composite score), and cognitive-specific domains (executive function, memory, visuospatial function, attention, and language). Higher white matter rostral middle frontal PVS was associated with lower scores in both global cognitive and visuospatial function. In the basal ganglia higher PVS was associated with lower scores for memory with a trend towards lower global cognitive composite score. While previous reports have shown that greater amount of PVS in the basal ganglia is associated with decline in global cognition in PD, our findings suggest that increased white matter PVS volume may also underlie changes in cognition.


Assuntos
Sistema Glinfático , Doença de Parkinson , Substância Branca , Humanos , Doença de Parkinson/complicações , Substância Branca/patologia , Sistema Glinfático/diagnóstico por imagem , Sistema Glinfático/patologia , Imageamento por Ressonância Magnética/métodos , Cognição , Gânglios da Base/diagnóstico por imagem
13.
Stroke Vasc Neurol ; 9(1): 8-17, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-37188388

RESUMO

INTRODUCTION: It remains unclear whether enlarged perivascular spaces (EPVS) predict poor clinical outcomes in patients with acute ischaemic stroke (AIS) or transient ischaemic attack (TIA). METHOD: Data were obtained from the Third China National Stroke Registry study. We estimated EPVS in basal ganglia (BG) and centrum semiovale (CSO) using a semiquantified scale (Grade from 0 to 4). Using Cox and logistic regression analyses, the associations of EPVS with 3-month and 1-year adverse outcomes (including recurrent stroke, ischaemic stroke, haemorrhagic stroke, combined vascular event, disability and mortality) were explored. Sensitivity analyses of any association of cerebral small vessel disease at baseline and development of a small arterial occlusion (SAO) were conducted. RESULT: Among 12 603 patients with AIS/TIA, median age was 61.7±11.6 years, and 68.2% were men. After adjusting for all potential confounders, frequent-to-severe BG-EPVS was associated with a decreased risk of recurrent ischaemic stroke (HR 0.71, 95% CI 0.55 to 0.92, p=0.01) but an increased risk of haemorrhagic stroke (HR 1.99, 95% CI 1.11 to 3.58, p=0.02) at 1 year after AIS/TIA, compared with none-to-mild BG-EPVS. Patients with frequent-to-severe CSO-EPVS had a decreased risk of disability (OR 0.76, 95% CI 0.62 to 0.92, p=0.004) and all-cause death (HR 0.55, 95% CI 0.31 to 0.98, p=0.04) within 3-month but not 1-year follow-ups, compared with those with none-to-mild BG-EPVS. Sensitivity analyses showed that both BG-EPVS (HR 0.43, 95% CI 0.21 to 0.87, p=0.02) and CSO-EPVS (HR 0.58, 95% CI 0.35 to 0.95, p=0.03) were associated with a decreased risk of subsequent ischaemic stroke in patients with SAO during 1-year follow-up. CONCLUSION: BG-EPVS increased the risk of haemorrhagic stroke in patients already with AIS/TIA within 1 year. Therefore, caution is recommended when selecting antithrombotic agents for secondary stroke prevention in patients with AIS/TIA and more severe BG-EPVS.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral Hemorrágico , Ataque Isquêmico Transitório , AVC Isquêmico , Acidente Vascular Cerebral , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Feminino , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/etiologia , Acidente Vascular Cerebral Hemorrágico/diagnóstico por imagem , Ataque Isquêmico Transitório/diagnóstico por imagem , Ataque Isquêmico Transitório/etiologia , Imageamento por Ressonância Magnética , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/etiologia , Gânglios da Base/diagnóstico por imagem
14.
Brain ; 147(3): 871-886, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-37757883

RESUMO

Dopaminergic dysfunction in the basal ganglia, particularly in the posterior putamen, is often viewed as the primary pathological mechanism behind motor slowing (i.e. bradykinesia) in Parkinson's disease. However, striatal dopamine loss fails to account for interindividual differences in motor phenotype and rate of decline, implying that the expression of motor symptoms depends on additional mechanisms, some of which may be compensatory in nature. Building on observations of increased motor-related activity in the parieto-premotor cortex of Parkinson patients, we tested the hypothesis that interindividual differences in clinical severity are determined by compensatory cortical mechanisms and not just by basal ganglia dysfunction. Using functional MRI, we measured variability in motor- and selection-related brain activity during a visuomotor task in 353 patients with Parkinson's disease (≤5 years disease duration) and 60 healthy controls. In this task, we manipulated action selection demand by varying the number of possible actions that individuals could choose from. Clinical variability was characterized in two ways. First, patients were categorized into three previously validated, discrete clinical subtypes that are hypothesized to reflect distinct routes of α-synuclein propagation: diffuse-malignant (n = 42), intermediate (n = 128) or mild motor-predominant (n = 150). Second, we used the scores of bradykinesia severity and cognitive performance across the entire sample as continuous measures. Patients showed motor slowing (longer response times) and reduced motor-related activity in the basal ganglia compared with controls. However, basal ganglia activity did not differ between clinical subtypes and was not associated with clinical scores. This indicates a limited role for striatal dysfunction in shaping interindividual differences in clinical severity. Consistent with our hypothesis, we observed enhanced action selection-related activity in the parieto-premotor cortex of patients with a mild-motor predominant subtype, both compared to patients with a diffuse-malignant subtype and controls. Furthermore, increased parieto-premotor activity was related to lower bradykinesia severity and better cognitive performance, which points to a compensatory role. We conclude that parieto-premotor compensation, rather than basal ganglia dysfunction, shapes interindividual variability in symptom severity in Parkinson's disease. Future interventions may focus on maintaining and enhancing compensatory cortical mechanisms, rather than only attempting to normalize basal ganglia dysfunction.


Assuntos
Doença de Parkinson , Humanos , Doença de Parkinson/diagnóstico por imagem , Hipocinesia , Gânglios da Base/diagnóstico por imagem , Corpo Estriado , Dopamina , Putamen
15.
Eur J Neurol ; 31(2): e16111, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37903090

RESUMO

BACKGROUND AND PURPOSE: Cerebral infarction in the basal ganglia may cause secondary and delayed neuronal degeneration in the substantia nigra (SN). However, the clinical significance of SN degeneration remains poorly understood. METHODS: This retrospective observational study included patients with acute ischemic stroke in the basal ganglia on initial diffusion-weighted imaging who underwent follow-up diffusion-weighted imaging between 4 and 30 days after symptom onset. SN degeneration was defined as a hyperintensity lesion in the SN observed on diffusion-weighted imaging. We compared functional outcomes at 3 months between patients with and without SN degeneration. A poor outcome was defined as a score of 3-6 (functional dependence or death) on the modified Rankin Scale. RESULTS: Of 350 patients with basal ganglia infarction (median age = 74.0 years, 53.7% male), 125 (35.7%) had SN degeneration. The proportion of functional dependence or death was 79.2% (99/125 patients) in patients with SN degeneration, which was significantly higher than that in those without SN degeneration (56.4%, 127/225 patients, p < 0.001). SN degeneration was more frequent in patients with functional dependence or death (99/226 patients, 43.8%) than in those with functional independence (26/124 patients, 21.0%, p < 0.001). Multivariable logistic regression analysis showed a significant association between SN degeneration and functional dependence or death (odds ratio = 2.91, 95% confidence interval = 1.17-7.21, p = 0.021). CONCLUSIONS: The study showed that patients with degeneration of SN were associated with functional dependence or death at 3 months, suggesting that secondary degeneration is a predictor of poor stroke outcomes and a potential therapeutic target.


Assuntos
AVC Isquêmico , Idoso , Feminino , Humanos , Masculino , Gânglios da Base/diagnóstico por imagem , Gânglios da Base/patologia , Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/patologia , Imagem de Difusão por Ressonância Magnética , Substância Negra/diagnóstico por imagem , Substância Negra/patologia , Estudos Retrospectivos
16.
Neuroimage ; 285: 120478, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38036152

RESUMO

Brain regions accumulate different amounts of iron with age, with older adults having higher iron in the basal ganglia (globus pallidus, putamen, caudate) relative to the hippocampus. This has important implications for functional magnetic resonance imaging (fMRI) studies in aging as the presence of iron may influence both neuronal functioning as well as the measured fMRI (BOLD) signal, and these effects will vary across age groups and brain regions. To test this hypothesis, the current study examined the effect of iron on age group differences in task-related activity within each basal nuclei and the hippocampus. Twenty-eight younger and 22 older adults completed an associative learning task during fMRI acquisition. Iron content (QSM, R2*) was estimated from a multi-echo gradient echo sequence. As previously reported, older adults learned significantly less than younger adults and age group differences in iron content were largest in the basal ganglia (putamen, caudate). In the hippocampus (early task stage) and globus pallidus (late task stage), older adults had significantly higher learning-related activity than younger adults both before and after controlling for iron. In the putamen (late task stage), however, younger adults had significantly higher learning-related activity than older adults that was only seen after controlling for iron. These findings support the notion that age-related differences in iron influence both neuronal functioning and the measured fMRI signal in select basal nuclei. Moreover, previous fMRI studies in aging populations may have under-reported age group differences in task-related activity by not accounting for iron within these regions.


Assuntos
Ferro , Imageamento por Ressonância Magnética , Humanos , Idoso , Imageamento por Ressonância Magnética/métodos , Mapeamento Encefálico/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Gânglios da Base/diagnóstico por imagem , Envelhecimento/fisiologia
17.
Brain Imaging Behav ; 18(1): 220-230, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37993754

RESUMO

Parkinson's Disease (PD) is hallmarked by dysfunctional circuitry between the basal ganglia and dorsolateral-prefrontal cortex. Recently progress has been made in understanding factors contributing to differential susceptibility to pathology mitigating disease-related cognitive decline. Cognitive reserve, the brain processing resources accumulated throughout life while engaged in mentally stimulating activities, can play an important protective role in cognitive performance. We tested the hypothesis that Cognitive Reserve proxies may exert an impact on the basal ganglia and dorsolateral-prefrontal atrophy in early PD. Forty-five early patients with PD and 20 age-gender-matched healthy controls (HC) completed the Cognitive Reserve Index questionnaire to quantify Cognitive Reserve proxies by three indexes (CRI-Education, CRI-Working Activity, CRI-Leisure Time) and a structural MRI examination (3T). Morphometrical indexes for basal ganglia (bilateral putamen, caudate, pallidum volume) and dorsolateral-prefrontal cortex (cortical thickness) were computed. Significant differences between HC and PD were tested by direct comparisons in demographics, cognitive level, and cognitive reserve proxies indexes. Then two multiple regression analyses were performed to identify predictors of the basal ganglia and dorsolateral-prefrontal cortex structural integrity. Regression analysis revealed that basal ganglia volume was significantly predicted by CRI-Education (pFDR = 0.029), sex (pFDR = 0.029), and Total Intracranial Volume (pFDR < 0.001). Instead, the dorsolateral-prefrontal thickness was predicted by CRI-Leisure Time (pFDR = 0.030) and age (pFDR = 0.010). Cognitive Reserve proxies, especially education and leisure-time activities, can play a protective role on the structural integrity of the basal ganglia and dorsolateral-prefrontal cortex, respectively, critical regions hallmarking brain status of early phases of PD.


Assuntos
Reserva Cognitiva , Doença de Parkinson , Humanos , Imageamento por Ressonância Magnética , Gânglios da Base/diagnóstico por imagem , Encéfalo
18.
Int J Comput Assist Radiol Surg ; 19(3): 433-442, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37982960

RESUMO

PURPOSE: Accurate and automatic segmentation of basal ganglia from magnetic resonance (MR) images is important for diagnosis and treatment of various brain disorders. However, the basal ganglia segmentation is a challenging task because of the class imbalance and the unclear boundaries among basal ganglia anatomical structures. Thus, we aim to present an encoder-decoder convolutional neural network (CNN)-based method for improved segmentation of basal ganglia by focusing on skip connections that determine the segmentation performance of encoder-decoder CNNs. We also aim to reveal the effect of skip connections on the segmentation of basal ganglia with unclear boundaries. METHODS: We used the encoder-decoder CNNs with the following five patterns of skip connections: without skip connection, with full-resolution horizontal skip connection, with horizontal skip connections, with vertical skip connections, and with crossover-typed skip connections (the proposed method). We compared and evaluated the performance of the CNNs in the experiment of basal ganglia segmentation using T1-weighted MR brain images of 79 patients. RESULTS: The experimental results showed that the skip connections at each scale level help CNNs to acquire multi-scale image features, the vertical skip connections contribute on acquiring finer image features for segmentation of smaller anatomical structures with more blurred boundaries, and the crossover-typed skip connections, a combination of horizontal and vertical skip connections, provided better segmentation accuracy. CONCLUSION: This paper investigated the effect of skip connections on the basal ganglia segmentation and revealed the crossover-typed skip connections might be effective for improving the segmentation of basal ganglia with the class imbalance and the unclear boundaries.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Gânglios da Base/diagnóstico por imagem
19.
JAMA Neurol ; 81(1): 81-82, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37983040

RESUMO

This case report describes reversible cortical and basal ganglia lesions in late-onset methylmalonic aciduria in a man in his mid-40s.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos , Humanos , Erros Inatos do Metabolismo dos Aminoácidos/complicações , Gânglios da Base/diagnóstico por imagem
20.
Brain Imaging Behav ; 18(1): 19-33, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37821673

RESUMO

This study intended to investigate the frequency specific brain oscillation activity in patients with acute basal ganglia ischemic stroke (BGIS) by using the degree centrality (DC) method. A total of 34 acute BGIS patients and 44 healthy controls (HCs) underwent resting-state functional magnetic resonance imaging (rs-fMRI) scanning. The DC values in three frequency bands (conventional band: 0.01-0.08 Hz, slow­4 band: 0.027-0.073 Hz, slow­5 band: 0.01-0.027 Hz) were calculated. A two-sample t-test was used to explore the between-group differences in the conventional frequency band. A two-way repeated-measures analysis of variance (ANOVA) was used to analyze the DC differences between groups (BGIS patients, HCs) and bands (slow­4, slow­5). Moreover, correlations between DC values and clinical indicators were performed. In conventional band, the DC value in the right middle temporal gyrus was decreased in BGIS patients compared with HCs. Significant differences of DC were observed between the two bands mainly in the bilateral cortical brain regions. Compared with the HCs, the BGIS patients showed increased DC in the right superior temporal gyrus and the left precuneus, but decreased mainly in the right inferior temporal gyrus, right inferior occipital gyrus, right precentral, and right supplementary motor area. Furthermore, the decreased DC in the right rolandic operculum in slow-4 band and the right superior temporal gyrus in slow-5 band were found by post hoc two-sample t-test of main effect of group. There was no significant correlation between DC values and clinical scales after Bonferroni correction. Our findings showed that the DC changes in BGIS patients were frequency specific. Functional abnormalities in local brain regions may help us to understand the underlying pathogenesis mechanism of brain functional reorganization of BGIS patients.


Assuntos
AVC Isquêmico , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Mapeamento Encefálico , Encéfalo/diagnóstico por imagem , Gânglios da Base/diagnóstico por imagem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA