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1.
Artigo em Inglês | MEDLINE | ID: mdl-38876805

RESUMO

AIMS: This study aimed to demonstrate the feasibility and evaluate the dosimetric effect and clinical impact of dose-painting proton radiotherapy (PRT) guided by functional MRI in non-enhancing high-grade gliomas (NE-HGGs). MATERIALS AND METHODS: The 3D-ASL and T2 FLAIR MR images of ten patients with NE-HGGs before radiotherapy were studied retrospectively. The hyperintensity on T2 FLAIR was used to generate the planning target volume (PTV), and the high-perfusion volume on 3D-ASL (PTV-ASL) was used to generate the simultaneous integrated boost (SIB) volume. Each patient received pencil beam scanning PRT and photon intensity-modulated radiotherapy (IMRT). There were five plans in each modality: (1) Uniform plans (IMRT60 vs. PRT60): 60Gy in 30 fractions to the PTV. (2)-(5) SIB plans (IMRT72, 84, 96, 108 vs. PRT72, 84, 96, 108): Uniform plan plus additional dose boost to PTV-ASL in 30 fractions to 72, 84, 96, 108 Gy. The dosimetric differences between various plans were compared. The clinical effects of target volume and organs at risk (OARs) were assessed using biological models for both tumor control probability (TCP) and normal tissue complication probability (NTCP). RESULTS: Compared with the IMRT plan, the D2 and D50 of the PRT plans with the same prescription dose increased by 1.27-4.12% and 0.64-2.01%, respectively; the R30 decreased by > 32%; the dose of brainstem and chiasma decreased by > 27% and >32%; and the dose of normal brain tissue (Br-PTV), optic nerves, eyeballs, lens, cochlea, spinal cord, and hippocampus decreased by > 50% (P < 0.05). The maximum necessary dose was 96GyE to achieve >98% TCP for PRT, and it was 84Gy to achieve >91% TCP for IMRT. The average NTCP of Br-PTV was 1.30% and 1.90% for PRT and IMRT at the maximum dose escalation, respectively. The NTCP values of the remaining OARs approached zero in all PRT plans. CONCLUSION: The functional MRI-guided dose escalation using PRT is feasible while sparing the OARs constraints and demonstrates a potential clinical benefit by improving TCP with no or minimal increase in NCTP for tissues outside the PTV. This retrospective study suggested that the use of PRT-based SIB guided by functional MRI may represent a strategy to provide benefits for patients with NE-HGGs.

2.
Front Neurosci ; 17: 1221579, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37901419

RESUMO

Objective: Benign paroxysmal positional vertigo (BPPV) is a common clinical vertigo disease, and the most effective treatment for this disease is canal repositioning procedures (CRP). Most patients return to normal after a single treatment. However, some patients still experience residual dizziness (RD) after treatment, and this disease's pathogenesis is currently unclear. The purpose of this study is to explore whether there are abnormal brain functional activities in patients with RD by using resting-state functional magnetic resonance imaging (rs-fMRI) and to provide imaging evidence for the study of the pathogenesis of RD. Materials and methods: The BPPV patients in the Second Affiliated Hospital of Xuzhou Medical University had been included from December 2021 to November 2022. All patients had been received the collection of demographic and clinical characteristics (age, gender, involved semicircular canal, affected side, CRP times, BPPV course, duration of RD symptoms, and whether they had hypertension, diabetes, coronary heart disease.), scale assessment, including Dizziness Handicap Inventory (DHI), Hamilton Anxiety Inventory (HAMA), Hamilton Depression Inventory (HAMD), rs-fMRI data collection, CRP treatment, and then a one-month follow-up. According to the follow-up results, 18 patients with RD were included. At the same time, we selected 19 healthy individuals from our hospital's physical examination center who matched their age, gender as health controls (HC). First, the amplitude of low-frequency fluctuations (ALFF) analysis method was used to compare the local functional activities of the two groups of subjects. Then, the brain regions with different ALFF results were extracted as seed points. Functional connectivity (FC) analysis method based on seed points was used to explore the whole brain FC of patients with RD. Finally, a correlation analysis between clinical features and rs-fMRI data was performed. Results: Compared to the HC, patients with RD showed lower ALFF value in the right precuneus and higher ALFF value in the right superior temporal gyrus (STG). When using the right STG as a seed point, it was found that the FC between the right STG, the right supramarginal gyrus (SMG), and the left precuneus was decreased in RD patients. However, no significant abnormalities in the FC were observed when using the right precuneus as a seed point. Conclusion: In patients with RD, the local functional activity of the right precuneus is weakened, and the local functional activity of the right STG is enhanced. Furthermore, the FC between the right STG, the right SMG, and the left precuneus is weakened. These changes may explain the symptoms of dizziness, floating sensation, walking instability, neck tightness, and other symptoms in patients with RD to a certain extent.

3.
Front Neurosci ; 17: 1109684, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36875648

RESUMO

Objective: The central nervous system may also be involved in the pathogenesis of classical trigeminal neuralgia (CTN). The present study aimed to explore the characteristics of static degree centrality (sDC) and dynamic degree centrality (dDC) at multiple time points after a single triggering pain in CTN patients. Materials and methods: A total of 43 CTN patients underwent resting-state function magnetic resonance imaging (rs-fMRI) before triggering pain (baseline), within 5 s after triggering pain (triggering-5 s), and 30 min after triggering pain (triggering-30 min). Voxel-based degree centrality (DC) was used to assess the alteration of functional connection at different time points. Results: The sDC values of the right caudate nucleus, fusiform gyrus, middle temporal gyrus, middle frontal gyrus, and orbital part were decreased in triggering-5 s and increased in triggering-30 min. The sDC value of the bilateral superior frontal gyrus were increased in triggering-5 s and decreased in triggering-30 min. The dDC value of the right lingual gyrus was gradually increased in triggering-5 s and triggering-30 min. Conclusion: Both the sDC and dDC values were changed after triggering pain, and the brain regions were different between the two parameters, which supplemented each other. The brain regions which the sDC and dDC values were changing reflect the global brain function of CTN patients, and provides a basis for further exploration of the central mechanism of CTN.

4.
Curr Res Neurobiol ; 3: 100054, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36518336

RESUMO

The role of gender and the associated brain activation when witnessing cyberbullying requires investigation. The current study aimed to determine whether brain responses to cyberbullying differ according to gender and level of wellbeing. We hypothesised that females and males would activate different regions of the brain when witnessing cyberbullying, and that this would be influenced by wellbeing levels and prior cyberbullying experiences. Blood-oxygenation-level-dependent (BOLD) responses were examined in participants (N = 32, aged 18-25 years; 66% female) whilst observing cyberbullying versus neutral stimuli during a functional MRI. Results revealed significant correlations between BOLD signal and achievement scores among males, but not females, with previous experiences of cyberbullying, in regions including the cerebellum, the superior and inferior frontal gyrus, and the precuneus. Furthermore, males who previously cyberbullied others, with higher scores in achievement (a wellbeing sub-category), activated brain regions associated with executive function, social cognition, and self-evaluation, when viewing the cyberbullying stimuli. In addition, despite gender, BOLD signal in the cingulate gyrus was negatively correlated with cyberbullying scores, and BOLD signal in the left dorsal caudate and the cerebellum was independently and positively correlated with achievement scores. Taken together, these findings provide insights into brain responses to cyberbullying scenarios and emphasize that there are some significant variations according to gender. The overall finding that males activated brain regions linked to varying aspects of cognition, whereas females more often activated regions linked to emotion processing and empathy is important for future research in this area.

5.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 36(2): 101-105, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32743999

RESUMO

Objective: To investigate the effects of transcranial direct current stimulation (tDCS) on the disturbance of brain network dysfunction after sleep deprivation (SD). Methods: The experimental design of self-control was used in the study. All 16 subjects received 2 times of 24 h SD with an interval of 3 weeks. After the first normal sleep, 24 h SD and transcranial electrical stimulation (true or false stimulation) intervention (the current magnitude of true and false stimulation was 1 mA, and the action time was 20 min and 2 s, respectively. The intervention experiment lasted for 20 min. ) and the resting magnetic resonance imaging data were collected after the second transcranial electrical stimulation (sham or true stimulation). The resting fMRI data were collected as baseline before SD, the bilateral posterior cingulate cortex in the default mode network was selected as the seed point, and the functional connectivity between the seed points and the whole brain was calculated. Results: Compared with the rest wakefulness, the functional connectivity among bilateral posterior cingulate cortex, bilateral thalamus and hippocampus was increased (P<0. 01), but connected with the right precuneus, bilateral insula was decreased after 24 h SD (P<0. 01). Compared with the sham tDCS group, the functional connectivity between left posterior cingulate cortex seed point and right precuneus of tDCS group was increased (P<0. 01); but decreased with the bilateral thalamus, insula and right cerebral cortex (P<0. 01). There was a decrease in the functional connectivity among the right posterior cingulate cortex and the bilateral thalamus, right insula, and cerebral cortex(P<0. 01). Conclusion: 24-hours sleep deprivation can cause functional connection disorder of bilateral posterior cingulate gyrus, and transcranial electrical stimulation can improve the functional connection disorder after sleep deprivation to some extent.


Assuntos
Giro do Cíngulo/fisiopatologia , Privação do Sono , Estimulação Transcraniana por Corrente Contínua , Humanos , Imageamento por Ressonância Magnética
6.
Hum Brain Mapp ; 41(6): 1495-1504, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-31797458

RESUMO

There is a dearth of research that has investigated the neural correlates of cyberbullying, using task-based functional magnetic resonance imaging (fMRI) and, specifically, in a real-time context such as observing cyberbullying scenarios. This article presents pilot data from a novel protocol designed to undertake such research with the overall aim being to elucidate the neurobiological underpinnings of cyberbullying via task-based fMRI (tb-fMRI)) in passive cyberbystanders. Young adults (N = 32, 18 to 25 years old) viewed six negative (cyberbullying) and six neutral stimuli from the Cyberbullying Picture Series (CyPicS) while undergoing tb-fMRI. Our results revealed 12 clusters of significantly greater blood-oxygenation-level-dependent (BOLD) responses (family wise error corrected p FWE < .05) in participants when viewing cyberbullying stimuli compared to neutral stimuli, across a distributed network of regions including left and right middle temporal gyrus, default mode network hubs, left and right posterior cerebellum/vermis, and putamen. Further analysis also revealed greater BOLD response in females compared to males, as well as in those with no prior experience of cyberbullying compared to those with prior experience (despite gender), when viewing the cyberbullying stimuli compared to the neutral stimuli. These results bring us closer to understanding the neurobiological underpinnings that may be associated with cybervictim/bully status and outcomes.


Assuntos
Cyberbullying/psicologia , Adolescente , Adulto , Fatores Etários , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Oxigênio/sangue , Estimulação Luminosa , Projetos Piloto , Autorrelato , Caracteres Sexuais , Adulto Jovem
7.
Mov Disord ; 34(12): 1891-1900, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31584222

RESUMO

BACKGROUND: The objective of this study was to examine the effects of aerobic exercise on evoked dopamine release and activity of the ventral striatum using positron emission tomography and functional magnetic resonance imaging in Parkinson's disease (PD). METHODS: Thirty-five participants were randomly allocated to a 36-session aerobic exercise or control intervention. Each participant underwent an functional magnetic resonance imaging scan while playing a reward task before and after the intervention to determine the effect of exercise on the activity of the ventral striatum in anticipation of reward. A subset of participants (n = 25) completed [11 C] raclopride positron emission tomography scans to determine the effect of aerobic exercise on repetitive transcranial magnetic stimulation-evoked release of endogenous dopamine in the dorsal striatum. All participants completed motor (MDS-UPDRS part III, finger tapping, Timed-up-and-go) and nonmotor assessments (Starkstein Apathy Scale, Beck Depression Inventory, reaction time, Positive and Negative Affect Schedule, Trail Making Test [A and B], and Montreal Cognitive Assessment) before and after the interventions. RESULTS: The aerobic group exhibited increased activity in the ventral striatum during functional magnetic resonance imaging in anticipation of 75% probability of reward (P = 0.01). The aerobic group also demonstrated increased repetitive transcranial magnetic stimulation-evoked dopamine release in the caudate nucleus (P = 0.04) and increased baseline nondisplaceable binding potential in the posterior putamen of the less affected repetitive transcranial magnetic stimulation-stimulated hemisphere measured by position emission tomography (P = 0.03). CONCLUSIONS: Aerobic exercise alters the responsivity of the ventral striatum, likely related to changes to the mesolimbic dopaminergic pathway, and increases evoked dopamine release in the caudate nucleus. This suggests that the therapeutic benefits of exercise are in part related to corticostriatal plasticity and enhanced dopamine release. © 2019 International Parkinson and Movement Disorder Society.


Assuntos
Núcleo Caudado/metabolismo , Dopamina/metabolismo , Exercício Físico/fisiologia , Doença de Parkinson/metabolismo , Estriado Ventral/metabolismo , Idoso , Idoso de 80 Anos ou mais , Núcleo Caudado/diagnóstico por imagem , Terapia por Exercício , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/psicologia , Tomografia por Emissão de Pósitrons , Estudos Prospectivos , Tomografia Computadorizada por Raios X , Estimulação Magnética Transcraniana , Estriado Ventral/diagnóstico por imagem
8.
Mov Disord ; 33(12): 1945-1950, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30376184

RESUMO

BACKGROUND: The benefits of exercise in PD have been linked to enhanced dopamine (DA) transmission in the striatum. OBJECTIVE: To examine differences in DA release, reward signaling, and clinical features between habitual exercisers and sedentary subjects with PD. METHODS: Eight habitual exercisers and 9 sedentary subjects completed [11 C]raclopride PET scans before and after stationary cycling to determine exercise-induced release of endogenous DA in the dorsal striatum. Additionally, functional MRI assessed ventral striatum activation during reward anticipation. All participants completed motor (UPDRS III; finger tapping; and timed-up-and-go) and nonmotor (Beck Depression Inventory; Starkstein Apathy Scale) assessments. RESULTS: [11 C]Raclopride analysis before and after stationary cycling demonstrated greater DA release in the caudate nuclei of habitual exercisers compared to sedentary subjects (P < 0.05). Habitual exercisers revealed greater activation of ventral striatum during the functional MRI reward task (P < 0.05) and lower apathy (P < 0.05) and bradykinesia (P < 0.05) scores versus sedentary subjects. CONCLUSIONS: Habitual exercise is associated with preservation of motor and nonmotor function, possibly mediated by increased DA release. This study formulates a foundation for prospective, randomized controlled studies. © 2018 International Parkinson and Movement Disorder Society.


Assuntos
Imageamento por Ressonância Magnética , Doença de Parkinson/diagnóstico por imagem , Idoso , Núcleo Caudado/patologia , Núcleo Caudado/fisiopatologia , Dopamina/metabolismo , Exercício Físico , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Doença de Parkinson/complicações , Doença de Parkinson/patologia , Doença de Parkinson/fisiopatologia , Tomografia por Emissão de Pósitrons , Racloprida , Recompensa , Estriado Ventral/patologia , Estriado Ventral/fisiopatologia
9.
Front Psychiatry ; 9: 282, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30127752

RESUMO

Background: Patients with treatment-resistant schizophrenia (TRS) and non-treatment-resistant schizophrenia (NTRS) respond to antipsychotic drugs differently. Previous studies demonstrated that patients with TRS or NTRS exhibited abnormal neural activity in different brain regions. Accordingly, in the present study, we tested the hypothesis that a regional homogeneity (ReHo) approach could be used to distinguish between patients with TRS and NTRS. Methods: A total of 17 patients with TRS, 17 patients with NTRS, and 29 healthy controls (HCs) matched in sex, age, and education levels were recruited to undergo resting-state functional magnetic resonance imaging (RS-fMRI). ReHo was used to process the data. ANCOVA followed by post-hoc t-tests, receiver operating characteristic curves (ROC), and correlation analyses were applied for the data analysis. Results: ANCOVA analysis revealed widespread differences in ReHo among the three groups in the occipital, frontal, temporal, and parietal lobes. ROC results indicated that the optimal sensitivity and specificity of the ReHo values in the left postcentral gyrus, left inferior frontal gyrus/triangular part, and right fusiform could differentiate TRS from NTRS, TRS from HCs, and NTRS from HCs were 94.12 and 82.35%, 100 and 86.21%, and 82.35 and 93.10%, respectively. No correlation was found between abnormal ReHo and clinical symptoms in patients with TRS or NTRS. Conclusions: TRS and NTRS shared most brain regions with abnormal neural activity. Abnormal ReHo values in certain brain regions might be applied to differentiate TRS from NTRS, TRS from HC, and NTRS from HC with high sensitivity and specificity.

10.
Epilepsy Behav ; 76: 120-125, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28882722

RESUMO

OBJECTIVE: The purpose of this study was to investigate the relationship between alterations of functional brain network and cognition in patients with benign epilepsy with centrotemporal spikes (BECTS) as a function of spike-wave index (SWI) during slow wave sleep. METHODS: Resting-state functional magnetic resonance imaging (RS-fMRI) data and Intelligence Quotient (IQ) were collected from two groups of patients with BECTS, including a SWI<50% group (5 cases) and a SWI≥50% group (7 cases). The SWI was calculated from the long-term video-electroencephalogram monitoring (one sleep cycle was included at least). The RS-fMRI data were analyzed by regional homogeneity (ReHo) method. RESULTS: There were three main findings. Firstly, Full Intelligence Quotient (FIQ), Verbal Intelligence Quotient (VIQ), and Performance Intelligence Quotient (PIQ) of the SWI≥50% group were significantly lower than SWI<50% group (p<0.05). Secondly, there was a negative correlation between the FIQ, VIQ, PIQ, and SWI (p<0.05), and the FIQ, VIQ, and PIQ were not dependent on age, age of onset, disease course, years of education, and total number of seizures (p>0.05). Finally, compared with the SWI<50% group, the SWI≥50% group showed increased ReHo in the bilateral precentral gyrus, bilateral premotor area, bilateral subcortical structure, right temporal lobe, and bilateral insular lobe, while they showed decreased ReHo in the posterior cingulate cortex and posterior of right inferior temporal lobe. CONCLUSIONS: The alterations of functional brain network caused by the frequent discharges during slow wave sleep could affect cognition in patients with BECTS.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Cognição/fisiologia , Eletroencefalografia/métodos , Epilepsia Rolândica/diagnóstico por imagem , Epilepsia Rolândica/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Descanso , Adolescente , Mapeamento Encefálico , Córtex Cerebral/fisiopatologia , Feminino , Lobo Frontal/fisiopatologia , Humanos , Testes de Inteligência , Masculino , Lobo Temporal/fisiopatologia
11.
Neurocase ; 22(4): 362-8, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27362339

RESUMO

Seizure localization includes neuroimaging like electroencephalogram, and magnetic resonance imaging (MRI) with limited ability to characterize the epileptogenic network. Temporal clustering analysis (TCA) characterizes epileptogenic network congruent with interictal epileptiform discharges by clustering together voxels with transient signals. We generated epileptogenic areas for 12 of 13 epilepsy patients with TCA, congruent with different areas of seizure onset. Resting functional MRI (fMRI) scans are noninvasive, and can be acquired quickly, in patients with different levels of severity and function. Analyzing resting fMRI data using TCA is quick and can complement clinical methods to characterize the epileptogenic network.


Assuntos
Epilepsia/diagnóstico por imagem , Epilepsia/fisiopatologia , Neuroimagem Funcional/métodos , Hipocampo , Lobo Temporal , Adulto , Eletroencefalografia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Hipocampo/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/patologia , Lobo Temporal/fisiopatologia
12.
Front Hum Neurosci ; 10: 185, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27199708

RESUMO

The stop-signal paradigm has been widely adopted as a way to parametrically quantify the response inhibition process. To evaluate inhibitory function in realistic environmental settings, the current study compared stop-signal responses in two different scenarios: one uses simple visual symbols as go and stop signals, and the other translates the typical design into a battlefield scenario (BFS) where a sniper-scope view was the background, a terrorist image was the go signal, a hostage image was the stop signal, and the task instructions were to shoot at terrorists only when hostages were not present but to refrain from shooting if hostages appeared. The BFS created a threatening environment and allowed the evaluation of how participants' inhibitory control manifest in this realistic stop-signal task. In order to investigate the participants' brain activities with both high spatial and temporal resolution, simultaneous functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) recordings were acquired. The results demonstrated that both scenarios induced increased activity in the right inferior frontal gyrus (rIFG) and presupplementary motor area (preSMA), which have been linked to response inhibition. Notably, in right temporoparietal junction (rTPJ) we found both higher blood-oxygen-level dependent (BOLD) activation and synchronization of theta-alpha activities (4-12 Hz) in the BFS than in the traditional scenario after the stop signal. The higher activation of rTPJ in the BFS may be related to morality judgments or attentional reorienting. These results provided new insights into the complex brain networks involved in inhibitory control within naturalistic environments.

13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-670348

RESUMO

Objective To explore the abnormally functional brain regions of female patients with depression by resting state functional magnetic resonance imaging (fMRI),and analyze the correlation with the severity of depressive symptoms.Methods 32 female patients diagnosed with depressive disorder and 40 matched healthy controls completed resting state fMRI scans.The whole brain's regional homogeneity (ReHo) and amplitude of low-frequency fluctuation(ALFF) were calculated,and the correlation analysis be tween ReHo and ALFF of brain regions with significant difference and the severity of depressive symptoms was conducted.Results Compared with control group,the left precuneus/left cuneus (MNI:-18,-81,45),bilateral precentral gyrus (MNI:-58,-5,35 and 57,-6,33),left inferior parietal lobule (MNI:-42,-36,45) and right inferior temporal gyrus(MN1:60,-45,-18) (P<0.05,corrected by AlphaSim)in the case group showed significantly decreased ReHo,with statistical significance.Compared with control group,the left cuneus(MNI:-3,-87,30),right inferior temporal gyrus(MNI:60,-48,-18) and left precentral gyrus(MNI:-63,-3,26) (P<0.05,corrected by AlphasSim)in the case group showed significantly decreased ALFF.The ReHo in the right inferior temporal gyrus was negative correlated with the HAMD-17 total score and retarda tion factor(r=-0.484,P=0.017;r=-0.408,P=0.048),the ALFF in the right inferior temporal gyrus was positively correlated with weight factor(r=0.574,P=0.003),and negative correlated with the number of depressive episodes(r=-0.416,P=0.043).Conclusion Female with depression in resting state have several abnormally functional brain regions and the extent of damage is correlated with the severity of depressive symptoms.Combination of the two parameters may yield a more comprehensive pathophy-siological mechanism for depressive disorder.

14.
Biomed Mater Eng ; 26 Suppl 1: S1439-46, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26405906

RESUMO

Blood oxygenation level dependent functional MRI (BOLD fMRI) requires repeatedly scanning the same region to capture neuronal activities, so the sampling data is very sparse along the temporal direction, which offers an opportunity to accelerate the fMRI. In this paper, (k-t) space data is sparsely acquired and reconstructed for BOLD fMRI using a partial separability (PS) model with a ℓ2-norm constraint. The proposed approach achieves a high temporal resolution of 200 ms without compromising spatial resolution (3.5 × 3.5 × 4.0 mm(3)). A simulation based on the EPI data with the right finger tapping experiment demonstrates that the proposed method can realize high spatiotemporal fMRI with accurate reconstruction of the activation regions from highly undersampled data. Meanwhile, preliminary in vivo experiment results also demonstrate the potential application of the proposed method in fMRI.


Assuntos
Mapeamento Encefálico/métodos , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Córtex Motor/fisiologia , Movimento/fisiologia , Rede Nervosa/fisiologia , Simulação por Computador , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Modelos Neurológicos , Modelos Estatísticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Análise Espaço-Temporal
15.
Drug Alcohol Depend ; 153: 314-22, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26059463

RESUMO

BACKGROUND: Opioid analgesics are frequently prescribed for chronic pain. One expected consequence of long-term opioid use is the development of physical dependence. Although previous resting state functional magnetic resonance imaging (fMRI) studies have demonstrated signal changes in reward-associated areas following morphine administration, the effects of acute withdrawal on the human brain have been less well-investigated. In an earlier study by our laboratory, ondansetron was shown to be effective in preventing symptoms associated with opioid withdrawal. The purpose of this current study was to characterize neural activity associated with acute opioid withdrawal and examine whether these changes are modified by ondansetron. METHODS: Ten participants were enrolled in this placebo-controlled, randomized, double-blind, crossover study and attended three acute opioid withdrawal sessions. Participants received either placebo or ondansetron (8Ymg IV) before morphine administration (10Ymg/70Ykg IV). Participants then underwent acute naloxone-precipitated withdrawal during a resting state fMRI scan. Objective and subjective opioid withdrawal symptoms were assessed. RESULTS: Imaging results showed that naloxone-precipitated opioid withdrawal was associated with increased neural activity in several reward processing regions, including the right pregenual cingulate, putamen, and bilateral caudate, and decreased neural activity in networks involved in sensorimotor integration. Ondansetron pretreatment did not have a significant effect on the imaging correlates of opioid withdrawal. CONCLUSIONS: This study presents a preliminary investigation of the regional changes in neural activity during acute opioid withdrawal. The fMRI acute opioid withdrawal model may serve as a tool for studying opioid dependence and withdrawal in human participants.


Assuntos
Encéfalo/fisiopatologia , Neuroimagem Funcional , Imageamento por Ressonância Magnética , Vias Neurais/fisiopatologia , Recompensa , Síndrome de Abstinência a Substâncias/fisiopatologia , Adulto , Encéfalo/efeitos dos fármacos , Estudos Cross-Over , Método Duplo-Cego , Voluntários Saudáveis , Humanos , Masculino , Morfina/antagonistas & inibidores , Naloxona/efeitos adversos , Vias Neurais/efeitos dos fármacos , Ondansetron/uso terapêutico , Síndrome de Abstinência a Substâncias/tratamento farmacológico
16.
International Eye Science ; (12): 1413-1415, 2015.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-637206

RESUMO

AIM:To evaluate the recovery about the visual cortex function of stereopsis in anisometropic amblyopia after regular amblyopia treatment 6, 12 and 18mo with blood oxygenation level dependent - function magnetic resonance imaging techniques ( BOLD-fMRI) . METHODS: In this study, self-controlled study before and after treatment was used, and blocks-designed fMRI was performed on 11 children which was the first phase of research for amblyopic treatment. Functional MRI data were processed by using SPM8 which based on the Matlab 7. 12. 0. 635. Through the hypothesis drive method, the differences range of activated area in each group were compared by before and after amblyopia treatment matched t-test. RESULTS: The functional area that was left occipital lobe (BA18), middle occipital gyrus (BA19), limbic lobe (BA19), lingualis gyrus of the right occipital lobe (BA17) and the bilateral parietal lobe ( BA7 ) expanded after amblyopia treatment 6, 12mo, compared those treatment phase, mean t value was 1. 5762, 1. 6856 respectively (P CONCLUSION: In children anisometropic amblyopia, the speed of function reconstruction about visual cortical functional mediating stereopsis increase slowly after amblyopia treatment 1a.

17.
Journal of Medical Postgraduates ; (12): 1268-1275, 2015.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-484116

RESUMO

Objective The aim of this study was to investi-gate the changes of brain function in patients with drug-naive idiopath-ic epilepsy ( DNIE ) using resting-state functional MRI ( rs-fMRI ) amplitude of low-frequency fluctuation ( ALFF) , analyze the correlation of abnormal brain regions with the clinical variable ( disease course) , and gain a deeper insight into the pathophysiological mechanisms of idiopathic epilepsy. Methods This study included 25 cases of DNIE (15 males and 10 females) and 34 cases of drug idiopathic epilepsy (DIE, 22 males and 12 females).Another 25 healthy volunteers matched with the DNIE patients in sex, age, education and handedness were recruited as normal controls.The rs-fMRI data obtained from all the subjects were processed, subjected to ALFF analysis, and compared among the DNIE, DIE, and nor-mal control groups.The correlation was evaluated between the ALFF statistical brain mapping and the course of disease. Results Obvious differences were found in ALFF among the DNIE, DIE and control subjects.Compared with the normal controls, the DNIE pa-tients showed increased ALFF in the right inferior temporal gyrus, right lingual gyrus and right cuneus, but decreased ALFF in the right insula, left hippocampus, right midbrain, right middle frontal gyrus, left anterior cingulated gyrus, left middle cingulate gyrus and right inferior parietal lobule.In comparison with the DIE patients, those of the DNIE group exhibited increased ALFF in the left inferior occipital gyrus, right middle occipital gyrus and left middle occipital gyrus, but decreased ALFF in the right inferior frontal gyrus, left insula, right superior temporal gyrus and right middle frontal gyrus.In the DNIE patients, the disease course was found to be correlated positively with ALFF in the right cerebellum posterior lobe, left cerebellar tonsil, right lingual gyrus, left orbital gyrus, left middle oc-cipital gyrus, left corpus callosum, left caudate nuclear, left superior frontal gyrus, left medial frontal gyrus, right precuneus and left middle frontal gyrus, but negatively with ALFF in the right parahippocampal, right superior temporal gyrus, left superior temporal gyrus and right post-central gyrus. Conclusion The ALFF of resting-state cerebral function is abnormal in DNIE patients.The correlation between ALFF and the clinical variable ( disease course) provides a new insight into the pathophysiological mechanisms of epilepsy.

18.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-934848

RESUMO

@#Objective To observe the relationship between spinal cord cystic degeneration, spinal cord movement improvement and apparent diffusion coefficient (ADC) values after early cervical spinal cord injury. Methods 18 patients with early cervical spinal cord injury were examined with MRI T1WI, T2WI and diffusion weighted imaging (DWI). Then ADC values and ADC maps were obtained. Their ASIA motor scores were also recorded. The relationship between spinal cord cystic degeneration and spinal cord movement improvement and ADC values was analyzed. Results ADC values were lower in those with cystic degeneration than without cystic degeneration in early cervical spinal cord injury, and the cut-off point was 700×10-6 mm2/s. ADC values were positively correlated with age. The movement improvement did not obviously correlate with ADC values. Conclusion ADC values of early cervical spinal cord injury are less than 700×10-6 mm2/s when cystic degeneration happened. Motor function recovery of patients with early cervical spinal cord injury cannot be estimated by measuring ADC values.

19.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-447902

RESUMO

Objective To explore the abnormally functional brain region in resting state in first-episode major depression disorder patients with function magnetic resonance imaging.Methods 51 patients diagnosed with first-episode major depression disorder according to DSM-Ⅳ and 50 gender-,age-,and education-matched healthy controls completed resting state fMRI scan.The severity of depression,and unpredicted homodynamic responses across the whole brain were analyzed using Hamilton depression scale,regional homogeneity and amplitude of low-frequency fluctuation,respectively.Results Compared with control group,the right medial frontal gyms (BA6,MNI:3,-3,63,K=34) and left medial frontal gyrus(BA9,MNI:-9,36,30,K=10) (P<0.001,uncorrected) in the case group showed higher regional homogeneity,with statistical significance.Compared with control group,right medial frontal gyrus (BA6,MNI:3,-3,63,K =35) and right posterior cingulated gyrus (BA31,MNI:3,-36,36,K =11) (P< 0.001,uncorrected)in the case group showed higher amplitude of low-frequency fluctuation,with statistical significance.Conclusion First-episode major depression disorder patients in resting state had several abnormally functional brain regions,which might be related to the pathological mechanism of depression disorder.

20.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-974841

RESUMO

@#ObjectiveTo investigate the pathologic mechanism of motor aphasia.Methods25 patients with cerebral infarction and motor aphasia were examined by magnetic resonance spectroscopy (MRS) and perfusion weighted imaging (PWI) at Broca's areas, the results were compared with that of the mirror side.ResultsMRS showed that the N-acetyl aspartate, choline in Broca's areas reduced than that of the mirror side ( P<0.05); while PWI showed that the regional cerebral blood volume and regional cerebral blood flow of damaged Broca's areas decreased significantly than that of the right hemisphere ( P<0.01). Mean transit time and time to peak of damaged Broca's areas prolonged than that of mirror side ( P<0.05).ConclusionHypoperfusion and hypometabolism revealed in Broca's areas of patients with motor aphasia may be one of the mechanisms of motor aphasia.

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