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1.
Epilepsia ; 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34642939

RESUMO

OBJECTIVE: To identify functional and structural alterations in language networks of people with temporal lobe epilepsy (TLE), who frequently present with naming and word-finding difficulties. METHODS: Fifty-five patients with unilateral TLE (29 left) and 16 controls were studied with auditory and picture naming functional magnetic resonance imaging (fMRI) tasks. Activation maxima in the left posterobasal temporal lobe were used as seed regions for whole-brain functional connectivity analyses (psychophysiological interaction). White matter language pathways were investigated using diffusion tensor imaging and neurite orientation dispersion and density imaging metrics extracted along fiber bundles starting from fMRI-guided seeds. Regression analyses were performed to investigate the correlation of functional connectivity with diffusion MRI metrics. RESULTS: In the whole group of patients and controls, weaker functional connectivity from the left posterobasal temporal lobe (1) to the bilateral anterior temporal lobe, precentral gyrus, and lingual gyrus during auditory naming and (2) to the bilateral occipital cortex and right fusiform gyrus during picture naming was associated with decreased neurite orientation dispersion and higher free water fraction of white matter tracts. Compared to controls, TLE patients exhibited fewer structural connections and an impaired coupling of functional and structural metrics. SIGNIFICANCE: TLE is associated with an impairment and decoupling of functional and structural language networks. White matter damage, as evidenced by diffusion abnormalities, may contribute to impaired functional connectivity and language dysfunction in TLE.

2.
Brain Imaging Behav ; 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34478055

RESUMO

Unilateral temporal lobe epilepsy (TLE) is the most common type of focal epilepsy characterized by foci in the unilateral temporal lobe grey matters of regions such as the hippocampus. However, it remains unclear how the functional features of white matter are altered in TLE. In the current study, resting-state functional magnetic resonance imaging (fMRI) was performed on 71 left TLE (LTLE) patients, 79 right TLE (RTLE) patients and 47 healthy controls (HC). Clustering analysis was used to identify fourteen white matter networks (WMN). The functional connectivity (FC) was calculated among WMNs and between WMNs and grey matter. Furthermore, the FC laterality of hemispheric WMNs was assessed. First, both patient groups showed decreased FCs among WMNs. Specifically, cerebellar white matter illustrated decreased FCs with the cerebral superficial WMNs, implying a dysfunctional interaction between the cerebellum and the cerebral cortex in TLE. Second, the FCs between WMNs and the ipsilateral hippocampus (grey matter foci) were also reduced in patient groups, which may suggest insufficient functional integration in unilateral TLE. Interestingly, RTLE showed more severe abnormalities of white matter FCs, including links to the bilateral hippocampi and temporal white matter, than LTLE. Taken together, these findings provide functional evidence of white matter abnormalities, extending the understanding of the pathological mechanism of white matter impairments in unilateral TLE.

3.
Epilepsy Behav ; 115: 107602, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33279440

RESUMO

In this cohort study, we aim to compare outcomes from coronavirus disease 2019 (COVID-19) in people with severe epilepsy and other co-morbidities living in long-term care facilities which all implemented early preventative measures, but different levels of surveillance. During 25-week observation period (16 March-6 September 2020), we included 404 residents (118 children), and 1643 caregivers. We compare strategies for infection prevention, control, and containment, and related outcomes, across four UK long-term care facilities. Strategies included early on-site enhancement of preventative and infection control measures, early identification and isolation of symptomatic cases, contact tracing, mass surveillance of asymptomatic cases and contacts. We measured infection rate among vulnerable people living in the facilities and their caregivers, with asymptomatic and symptomatic cases, including fatality rate. We report 38 individuals (17 residents) who tested severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-positive, with outbreaks amongst residents in two facilities. At Chalfont Centre for Epilepsy (CCE), 10/98 residents tested positive: two symptomatic (one died), eight asymptomatic on weekly enhanced surveillance; 2/275 caregivers tested positive: one symptomatic, one asymptomatic. At St Elizabeth's (STE), 7/146 residents tested positive: four symptomatic (one died), one positive during hospital admission for symptoms unrelated to COVID-19, two asymptomatic on one-off testing of all 146 residents; 106/601 symptomatic caregivers were tested, 13 positive. In addition, during two cycles of systematically testing all asymptomatic carers, four tested positive. At The Meath (TM), 8/80 residents were symptomatic but none tested; 26/250 caregivers were tested, two positive. At Young Epilepsy (YE), 8/80 children were tested, all negative; 22/517 caregivers were tested, one positive. Infection outbreaks in long-term care facilities for vulnerable people with epilepsy can be quickly contained, but only if asymptomatic individuals are identified through enhanced surveillance at resident and caregiver level. We observed a low rate of morbidity and mortality, which confirmed that preventative measures with isolation of suspected and confirmed COVID-19 residents can reduce resident-to-resident and resident-to-caregiver transmission. Children and young adults appear to have lower infection rates. Even in people with epilepsy and multiple co-morbidities, we observed a high percentage of asymptomatic people suggesting that epilepsy-related factors (anti-seizure medications and seizures) do not necessarily lead to poor outcomes.


Assuntos
COVID-19/epidemiologia , Epilepsia/epidemiologia , Controle de Infecções/tendências , Assistência de Longa Duração/tendências , Instituições Residenciais/tendências , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/terapia , Estudos de Coortes , Comorbidade , Epilepsia/terapia , Feminino , Humanos , Controle de Infecções/métodos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Reino Unido/epidemiologia , Adulto Jovem
4.
J Neurol ; 268(1): 147-160, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32747979

RESUMO

OBJECTIVE: To investigate alterations of language networks and their relation to impaired naming performance in temporal lobe epilepsy (TLE) using functional MRI. METHODS: Seventy-two adult TLE patients (41 left) and 36 controls were studied with overt auditory and picture naming fMRI tasks to assess temporal lobe language areas, and a covert verbal fluency task to probe frontal lobe language regions. Correlation of fMRI activation with clinical naming scores, and alteration of language network patterns in relation to epilepsy duration, age at onset and seizure frequency, were investigated with whole-brain multiple regression analyses. RESULTS: Auditory and picture naming fMRI activated the left posterior temporal lobe, and stronger activation correlated with better clinical naming scores. Verbal fluency MRI mainly activated frontal lobe regions. In left and right TLE, a later age of epilepsy onset related to stronger temporal lobe activations, while earlier age of onset was associated with impaired deactivation of extratemporal regions. In left TLE patients, longer disease duration and higher seizure frequency were associated with reduced deactivation. Frontal lobe language networks were unaffected by disease characteristics. CONCLUSIONS: While frontal lobe language regions appear spared, temporal lobe language areas are susceptible to dysfunction and reorganisation, particularly in left TLE. Early onset and long duration of epilepsy, and high seizure frequency, were associated with compromised activation and deactivation patterns of task-associated regions, which might account for impaired naming performance in individuals with TLE.


Assuntos
Epilepsia do Lobo Temporal , Adulto , Mapeamento Encefálico , Epilepsia do Lobo Temporal/complicações , Epilepsia do Lobo Temporal/diagnóstico por imagem , Lateralidade Funcional , Humanos , Idioma , Imageamento por Ressonância Magnética
5.
Epilepsia ; 61(7): 1438-1452, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32584424

RESUMO

OBJECTIVE: Juvenile myoclonic epilepsy (JME) is the most common genetic generalized epilepsy syndrome. Myoclonus may relate to motor system hyperexcitability and can be provoked by cognitive activities. To aid genetic mapping in complex neuropsychiatric disorders, recent research has utilized imaging intermediate phenotypes (endophenotypes). Here, we aimed to (a) characterize activation profiles of the motor system during different cognitive tasks in patients with JME and their unaffected siblings, and (b) validate those as endophenotypes of JME. METHODS: This prospective cross-sectional investigation included 32 patients with JME, 12 unaffected siblings, and 26 controls, comparable for age, sex, handedness, language laterality, neuropsychological performance, and anxiety and depression scores. We investigated patterns of motor system activation during episodic memory encoding and verb generation functional magnetic resonance imaging (fMRI) tasks. RESULTS: During both tasks, patients and unaffected siblings showed increased activation of motor system areas compared to controls. Effects were more prominent during memory encoding, which entailed hand motion via joystick responses. Subgroup analyses identified stronger activation of the motor cortex in JME patients with ongoing seizures compared to seizure-free patients. Receiver-operating characteristic curves, based on measures of motor activation, accurately discriminated both patients with JME and their siblings from healthy controls (area under the curve: 0.75 and 0.77, for JME and a combined patient-sibling group against controls, respectively; P < .005). SIGNIFICANCE: Motor system hyperactivation represents a cognitive, domain-independent endophenotype of JME. We propose measures of motor system activation as quantitative traits for future genetic imaging studies in this syndrome.


Assuntos
Cognição/fisiologia , Hipercinese/diagnóstico por imagem , Hipercinese/fisiopatologia , Epilepsia Mioclônica Juvenil/diagnóstico por imagem , Epilepsia Mioclônica Juvenil/fisiopatologia , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Estudos Transversais , Endofenótipos , Feminino , Humanos , Hipercinese/psicologia , Masculino , Pessoa de Meia-Idade , Epilepsia Mioclônica Juvenil/psicologia , Estudos Prospectivos , Adulto Jovem
6.
Epilepsia ; 61(4): 735-746, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32196657

RESUMO

OBJECTIVE: To examine the shared familial contribution to hippocampal and extrahippocampal morphological abnormalities in patients with sporadic temporal lobe epilepsy (TLE) and their unaffected siblings. METHODS: We collected clinical, electrophysiological, and T1-weighted magnetic resonance imaging (MRI) data of 18 sporadic patients with TLE without lesions other than hippocampal sclerosis (12 right, 6 left), their 18 unaffected full siblings, and 18 matched healthy volunteers. We compared between-group differences in cortical thickness and volumes of five subcortical areas (hippocampus, amygdala, thalamus, putamen, and pallidum). We determined the subregional extent of hippocampal abnormalities using surface shape analysis. All our imaging results were corrected for multiple comparisons using random field theory. RESULTS: We detected smaller hippocampal volumes in patients (right TLE: median right hippocampus 1.92 mL, interquartile range [IQR] 1.39-2.62, P < .001; left TLE: left hippocampus 2.05 mL, IQR 1.99-2.33, P = .01) and their unaffected siblings (right hippocampus 2.65 mL, IQR 2.32-2.80, P < .001; left hippocampus 2.39 mL, IQR 2.18-2.53, P < .001) compared to healthy controls (right hippocampus 2.94 mL, IQR 2.77-3.24; left hippocampus 2.71 mL, IQR 2.37-2.89). Surface shape analysis showed that patients with TLE had bilateral subregional atrophy in both hippocampi (right > left). Similar but less-pronounced subregional atrophy was detected in the right hippocampus of unaffected siblings. Patients with TLE had reduced cortical thickness in bilateral premotor/prefrontal cortices and the right precentral gyrus. Siblings did not show abnormalities in cortical or subcortical areas other than the hippocampus. SIGNIFICANCE: Our results demonstrate a shared vulnerability of the hippocampus in both patients with TLE and their unaffected siblings, pointing to a contribution of familial factors to hippocampal atrophy. This neuroimaging trait could represent an endophenotype of TLE, which might precede the onset of epilepsy in some individuals.


Assuntos
Epilepsia do Lobo Temporal/patologia , Hipocampo/anormalidades , Hipocampo/patologia , Irmãos , Adulto , Atrofia/patologia , Feminino , Humanos , Masculino
7.
Front Med ; 14(5): 630-641, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31912429

RESUMO

Mesial temporal lobe epilepsy (mTLE), the most common type of focal epilepsy, is associated with functional and structural brain alterations. Machine learning (ML) techniques have been successfully used in discriminating mTLE from healthy controls. However, either functional or structural neuroimaging data are mostly used separately as input, and the opportunity to combine both has not been exploited yet. We conducted a multimodal ML study based on functional and structural neuroimaging measures. We enrolled 37 patients with left mTLE, 37 patients with right mTLE, and 74 healthy controls and trained a support vector ML model to distinguish them by using each measure and the combinations of the measures. For each single measure, we obtained a mean accuracy of 74% and 69% for discriminating left mTLE and right mTLE from controls, respectively, and 64% when all patients were combined. We achieved an accuracy of 78% by integrating functional data and 79% by integrating structural data for left mTLE, and the highest accuracy of 84% was obtained when all functional and structural measures were combined. These findings suggest that combining multimodal measures within a single model is a promising direction for improving the classification of individual patients with mTLE.


Assuntos
Epilepsia do Lobo Temporal , Epilepsia do Lobo Temporal/diagnóstico por imagem , Lateralidade Funcional , Neuroimagem Funcional , Hipocampo , Humanos , Aprendizado de Máquina , Imageamento por Ressonância Magnética
8.
Front Neurol ; 10: 1203, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31798524

RESUMO

Pharmacological treatment with antiepileptic medications (AEDs) in epilepsy is associated with a variety of neurocognitive side effects. However, the mechanisms underlying these side effects, and why certain brain anatomies are more affected still remain poorly understood. Advanced functional magnetic resonance imaging (fMRI) methods, such as pharmaco-fMRI, can investigate medication-related effects on brain activities using task and resting state fMRI and showing reproducible activation and deactivation patterns. This methodological approach has been used successfully to complement neuropsychological studies of AEDs. Here we review pharmaco-fMRI studies in people with epilepsy targeting the most-widely prescribed AEDs. Pharmco-fMRI has advanced our understanding of the impact of AEDs on specific brain networks and thus may provide potential biomarkers to move beyond the current "trial and error" approach when commencing anti-epileptic medication.

9.
Brain ; 142(9): 2670-2687, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31365054

RESUMO

Juvenile myoclonic epilepsy is the most common genetic generalized epilepsy syndrome, characterized by a complex polygenetic aetiology. Structural and functional MRI studies demonstrated mesial or lateral frontal cortical derangements and impaired fronto-cortico-subcortical connectivity in patients and their unaffected siblings. The presence of hippocampal abnormalities and associated memory deficits is controversial, and functional MRI studies in juvenile myoclonic epilepsy have not tested hippocampal activation. In this observational study, we implemented multi-modal MRI and neuropsychological data to investigate hippocampal structure and function in 37 patients with juvenile myoclonic epilepsy, 16 unaffected siblings and 20 healthy controls, comparable for age, gender, handedness and hemispheric dominance as assessed with language laterality indices. Automated hippocampal volumetry was complemented by validated qualitative and quantitative morphological criteria to detect hippocampal malrotation, assumed to represent a neurodevelopmental marker. Neuropsychological measures of verbal and visuo-spatial learning and an event-related verbal and visual memory functional MRI paradigm addressed mesiotemporal function. We detected a reduction of mean left hippocampal volume in patients and their siblings compared with controls (P < 0.01). Unilateral or bilateral hippocampal malrotation was identified in 51% of patients and 50% of siblings, against 15% of controls (P < 0.05). For bilateral hippocampi, quantitative markers of verticalization had significantly larger values in patients and siblings compared with controls (P < 0.05). In the patient subgroup, there was no relationship between structural measures and age at disease onset or degree of seizure control. No overt impairment of verbal and visual memory was identified with neuropsychological tests. Functional mapping highlighted atypical patterns of hippocampal activation, pointing to abnormal recruitment during verbal encoding in patients and their siblings [P < 0.05, familywise error (FWE)-corrected]. Subgroup analyses indicated distinct profiles of hypoactivation along the hippocampal long axis in juvenile myoclonic epilepsy patients with and without malrotation; patients with malrotation also exhibited reduced frontal recruitment for verbal memory, and more pronounced left posterior hippocampal involvement for visual memory. Linear models across the entire study cohort indicated significant associations between morphological markers of hippocampal positioning and hippocampal activation for verbal items (all P < 0.05, FWE-corrected). We demonstrate abnormalities of hippocampal volume, shape and positioning in patients with juvenile myoclonic epilepsy and their siblings, which are associated with reorganization of function and imply an underlying neurodevelopmental mechanism with expression during the prenatal stage. Co-segregation of abnormal hippocampal morphology in patients and their siblings is suggestive of a genetic imaging phenotype, independent of disease activity, and can be construed as a novel endophenotype of juvenile myoclonic epilepsy.


Assuntos
Hipocampo/diagnóstico por imagem , Epilepsia Mioclônica Juvenil/diagnóstico por imagem , Epilepsia Mioclônica Juvenil/genética , Irmãos , Adolescente , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Epilepsy Behav ; 92: 311-326, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30738248

RESUMO

BACKGROUND: Epilepsy surgery is an important treatment option for people with drug-resistant epilepsy. Surgical procedures for epilepsy are underutilized worldwide, but it is far worse in low- and middle-income countries (LMIC), and it is less clear as to what extent people with drug-resistant epilepsy receive such treatment at all. Here, we review the existing evidence for the availability and outcome of epilepsy surgery in LMIC and discuss some challenges and priority. METHODS: We used an accepted six-stage methodological framework for scoping reviews as a guide. We searched PubMed, Embase, Global Health Archives, Index Medicus for South East Asia Region (IMSEAR), Index Medicus for Eastern Mediterranean Region (IMEMR), Latin American & Caribbean Health Sciences Literature (LILACS), African Journal Online (AJOL), and African Index Medicus (AIM) to identify the relevant literature. RESULTS: We retrieved 148 articles on epilepsy surgery from 31 countries representing 22% of the 143 LMIC. Epilepsy surgery appears established in some of these centers in Asia and Latin America while some are in their embryonic stage reporting procedures in a small cohort performed mostly by motivated neurosurgeons. The commonest surgical procedure reported was temporal lobectomies. The postoperative seizure-free rates and quality of life (QOL) are comparable with those in the high-income countries (HIC). Some models have shown that epilepsy surgery can be performed within a resource-limited setting through collaboration with international partners and through the use of information and communications technology (ICT). The cost of surgery is a fraction of what is available in HIC. CONCLUSION: This review has demonstrated the availability of epilepsy surgery in a few LMIC. The information available is inadequate to make any reasonable conclusion of its existence as routine practice. Collaborations with international partners can provide an opportunity to bring high-quality academic training and technological transfer directly to surgeons working in these regions and should be encouraged.


Assuntos
Países em Desenvolvimento/economia , Epilepsia Resistente a Medicamentos/economia , Epilepsia Resistente a Medicamentos/cirurgia , Saúde Global , Pobreza/economia , África/epidemiologia , Ásia/epidemiologia , Região do Caribe/epidemiologia , Epilepsia Resistente a Medicamentos/epidemiologia , Europa (Continente)/epidemiologia , Humanos , América Latina/epidemiologia , Pobreza/tendências , Qualidade de Vida
11.
Epilepsia ; 60(2): 246-254, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30653664

RESUMO

OBJECTIVE: To explore the real-time effects of interictal epileptiform discharges (IEDs) on hippocampus and amygdala functional connectivity (FC) in unilateral temporal lobe epilepsy (TLE). METHODS: Patients with unilateral TLE were recruited and underwent simultaneous electroencephalography-functional magnetic resonance imaging (EEG-fMRI) scanning. Simultaneous EEG was used to define the prespike (10 s before spike) and postspike (10 s after spike) periods. Dynamic FC analysis was applied using the left/right hippocampus and amygdala separately as a seed region to map the network alterations after IED occurrence. RESULTS: A total of 261 IED events (133 left, 128 right) from 21 patients with unilateral TLE (10 left, 11 right) were analyzed. Left IEDs had a greater influence on the hippocampus-seeded networks, whereas right IEDs affected the amygdala-seeded networks more. Left IEDs disconnected the ipsilateral hippocampus and the default mode network, which might be related to cognitive impairment in TLE. The reward-emotion network (more of the prefrontal-limbic system) and visual network also showed FC changes after left IEDs. The reward-emotion network (more of the reward system) was coactivated after right IEDs, indicating a possible mechanism of forced normalization. SIGNIFICANCE: This study directly linked the disrupted functional networks in TLE to epileptic activities and offered a unique tool for future research to investigate mechanisms of comorbidities in TLE.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Eletroencefalografia , Epilepsia do Lobo Temporal/fisiopatologia , Hipocampo/fisiopatologia , Imageamento por Ressonância Magnética , Adolescente , Adulto , Disfunção Cognitiva/fisiopatologia , Eletroencefalografia/métodos , Epilepsia/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Lobo Temporal/fisiopatologia
12.
Neuroimage Clin ; 21: 101631, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30553761

RESUMO

OBJECTIVES: To explore the dynamic changes of white matters following anterior temporal lobectomy (ATL) in mesial temporal lobe epilepsy (MTLE) patients who achieved seizure-free at two-year follow-up. METHODS: Diffusion tensor imaging (DTI) was obtained in ten MTLE patients at five serial time points: before surgery, three months, six months, 12 months and 24 months after surgery, as well as in 11 age- and sex-matched healthy controls at one time point. Regions with significant postoperative fractional anisotropy (FA) changes and their dynamic changes were confirmed by comparing all preoperative and postoperative data using Tract-Based Spatial Statistics (TBSS). RESULTS: After successful ATL, significant FA changes were found in widespread ipsilateral and contralateral white matter regions (P <.05, FWE correction). Ipsilateral external capsule, cingulum, superior corona radiate, body of corpus callosum, inferior longitudinal fasciculus, optic radiation and contralateral inferior cerebellar peduncle, inferior longitudinal fasciculus showed significant FA decrease at three months after surgery, without further changes. Ipsilateral superior cerebellar peduncle and contralateral corpus callosum, anterior corona radiate, external capsule, optic radiation showed significant FA decrease at three months follow up but increase later. Ipsilateral cerebral peduncle and contralateral middle cerebellar peduncle showed significant FA decrease at three months follow up, with further decrease after that. While ipsilateral posterior limb of internal capsule, retrolenticular part of internal capsule and contralateral posterior corona radiate showed significant FA increase after surgery. CONCLUSIONS: FA changes after successful ATL presented as four distinct patterns, reflecting different structural adaptions following epilepsy surgery. Some FA increases indicated the reversibility of preoperative diffusion abnormalities and the possibility of structural reorganization, especially in the contralateral hemisphere.


Assuntos
Imagem de Tensor de Difusão/tendências , Epilepsia do Lobo Temporal/diagnóstico por imagem , Epilepsia do Lobo Temporal/cirurgia , Cuidados Pós-Operatórios/tendências , Substância Branca/diagnóstico por imagem , Substância Branca/cirurgia , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Adulto Jovem
13.
Epilepsy Res ; 145: 178-184, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30048931

RESUMO

OBJECTIVES: Spontaneous low-frequency oscillations in different frequency bands have diverse physiological meanings. The amplitude of low-frequency fluctuation (ALFF) and functional connectivity (FC) in different frequency bands in Benign Childhood Epilepsy with Centrotemporal Spikes (BECTS) are unknown and worth exploring. METHOD: Resting-state functional magnetic resonance imaging data were collected in 51 drug-naïve BECTS patients and 76 healthy controls. The ALFF was calculated for the typical (0.01 - 0.08 Hz), slow-5 (0.01-0.027 Hz), slow-4 (0.027-0.073 Hz), and slow-3 (0.073-0.198 Hz) frequency bands. The bilateral precuneus/posterior cingulate cortex (PCU/PCC) showed a common alteration of ALFF in different frequency bands, and was selected as the seed for calculating FC per voxel. RESULTS: In the typical band, BECTS patients showed increased ALFF in the left rolandic operculum and the right pre/postcentral gyrus, and decreased ALFF in the bilateral PCU/PCC, some of which were shared by the slow-5, slow-4, and slow-3 bands. Decreased ALFF in the left angular gyrus was also found in the slow-3 band. Only the bilateral PCU/PCC showed a frequency-dependent correlation with the total seizure frequency and full-scale intelligence quotient. Regions having degenerated FC with the bilateral PCU/PCC in BECTS patients were mainly in the left prefrontal cortex and bilateral anterior cingulate cortex for the typical and slow-5 bands, and in the bilateral temporal limbic system and striatum for the slow-4 and slow-3 bands. CONCLUSION: Alteration of the ALFF and FC differed with distinct frequency bands. Therefore, employing different frequency bands would provide more meaningful findings for BECTS patients.


Assuntos
Mapeamento Encefálico , Sincronização de Fases em Eletroencefalografia/fisiologia , Epilepsia Rolândica/fisiopatologia , Descanso , Criança , Eletroencefalografia , Feminino , Humanos , Masculino , Estudos Retrospectivos
14.
Epilepsia ; 59(7): 1362-1371, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29897625

RESUMO

OBJECTIVE: To investigate the effects of sodium channel-blocking antiepileptic drugs (AEDs) on functional magnetic resonance imaging (fMRI) language network activations in patients with focal epilepsy. METHODS: In a retrospective study, we identified patients who were treated at the time of language fMRI scanning with either carbamazepine (CBZ; n = 42) or lamotrigine (LTG; n = 42), but not another sodium channel-blocking AED. We propensity-matched 42 patients taking levetiracetam (LEV) as "patient-controls" and included further 42 age- and gender-matched healthy controls. After controlling for age, age at onset of epilepsy, gender, and antiepileptic comedications, we compared verbal fluency fMRI activations between groups and out-of-scanner psychometric measures of verbal fluency. RESULTS: Patients on CBZ performed less well on a verbal fluency tests than those taking LTG or LEV. Compared to either LEV-treated patients or controls, patients taking CBZ showed decreased activations in left inferior frontal gyrus and patients on LTG showed abnormal deactivations in frontal and parietal default mode areas. All patient groups showed fewer activations in the putamen bilaterally compared to controls. In a post hoc analysis, out-of-scanner fluency scores correlated positively with left putamen activation. SIGNIFICANCE: Our study provides evidence of AED effects on the functional neuroanatomy of language, which might explain subtle language deficits in patients taking otherwise well-tolerated sodium channel-blocking agents. Patients on CBZ showed dysfunctional frontal activation and more pronounced impairment of performance than patients taking LTG, which was associated only with failure to deactivate task-negative networks. As previously shown for working memory, LEV treatment did not affect functional language networks.


Assuntos
Anticonvulsivantes/farmacologia , Encéfalo/efeitos dos fármacos , Cognição/efeitos dos fármacos , Imageamento por Ressonância Magnética , Rede Nervosa/efeitos dos fármacos , Adolescente , Adulto , Idoso , Anticonvulsivantes/efeitos adversos , Anticonvulsivantes/uso terapêutico , Carbamazepina/efeitos adversos , Carbamazepina/farmacologia , Carbamazepina/uso terapêutico , Relação Dose-Resposta a Droga , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Epilepsias Parciais/tratamento farmacológico , Feminino , Humanos , Lamotrigina/efeitos adversos , Lamotrigina/farmacologia , Lamotrigina/uso terapêutico , Levetiracetam/efeitos adversos , Levetiracetam/farmacologia , Levetiracetam/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
15.
Sci Rep ; 8(1): 5689, 2018 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-29632387

RESUMO

The aim of the current study was to find the epileptic focus and examine its causal relationship to other brain regions in children with new-onset benign childhood epilepsy with centrotemporal spikes (BECTS). Resting-state functional magnetic resonance imaging (fMRI) was performed in 66 children with BECTS and 37 matched control children. We compared the amplitude of low frequency fluctuation (ALFF) signals between the two groups to find the potential epileptogenic zone (EZ), then used Granger causality analysis (GCA) to explore the causal effects of EZ on the whole brain. Children with BECTS had significantly increased ALFF in the right Broca's area, and decreased ALFF in bilateral fusiform gyrus. The patients also showed increased driving effect from the EZ in Broca's area to the right prefrontal lobe, and decreased effects to the frontal lobe and posterior parts of the language network. The causal effect on left Wernicke's area negatively correlated with verbal IQ (VIQ) score. Our research on new-onset BECTS patients illustrates a possible compensatory mechanism in the language network at early stages of BECTS, and the negative correlation of GCA and VIQ suggest the disturbance of epileptiform activity on language. These findings shed light on the mechanisms of and language dysfunction in BECTS.


Assuntos
Mapeamento Encefálico/métodos , Epilepsia Rolândica/diagnóstico por imagem , Epilepsia Rolândica/psicologia , Lobo Temporal/diagnóstico por imagem , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Escalas de Wechsler
16.
Curr Pharm Des ; 23(37): 5727-5739, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28799517

RESUMO

BACKGROUND: Approximately one third of patients with epilepsy are refractory to medical treatment. Adverse effects associated with Anti-Epileptic Drugs (AEDs) are considered to affect quality of life often more than seizures themselves. Neuroimaging techniques, particularly Magnetic Resonance Imaging (MRI), have proven instrumental in clinical decision making in relation to epilepsy surgery, but may also provide further insights into the mechanisms underlying treatment response and side effects associated with AEDs. OBJECTIVE AND METHOD: We searched PubMed and Scopus databases for original articles and reviews published in the last two decades, which addressed the effects of AEDs on structural MRI, functional MRI and Magnetic Resonance Spectroscopy (MRS) measures. RESULTS: The majority of investigations implemented task-based fMRI, and probed the influence of widely used anti-epileptic drugs on tasks assessing language, executive functions and emotion recognition. Collectively, MRI allows detecting reproducible AED-related effects on regions and networks relevant to disease pathomechanisms, thus elucidating the anatomo-functional substrates of cognitive side effects. MRS analyses shed light on the molecular correlates of AED action, and may provide indicators of treatment response. CONCLUSION: MRI techniques have considerably improved our understanding of the effects of AEDs at a regional and network level, and provide biomarkers with potential to improve routine clinical decision making in epilepsy.


Assuntos
Anticonvulsivantes/uso terapêutico , Biomarcadores/análise , Epilepsia/tratamento farmacológico , Epilepsia/patologia , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Animais , Epilepsia/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador
17.
Seizure ; 44: 37-41, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28017580

RESUMO

Epilepsy has been recognized as a brain network disorder. Therefore, functional MRI (fMRI)-based connectivity is an ideal technique for exploring the complex effects of epilepsy on the brain. Functional connectivity studies have provided insights into the physiopathogenesis of the epileptic network underlying focal epilepsies, genetic generalized epilepsy, and specific epileptic syndromes. An increasing number of studies have focused on the deleterious effects of epilepsy on other brain networks to help to explain cognitive deficits and psychiatric symptoms. Anti-epileptic treatment studies have yielded information about the side effects and the restoration of functional abnormalities after using the drug. Researchers who have examined predictors of surgical outcomes have suggested that there might be identifiable pre-surgical patterns of functional connectivity that are associated with a greater likelihood of positive cognitive or seizure outcomes. However, knowledge regarding the role of fMRI connectivity remains limited in clinical settings. Further validation through invasive investigations and follow-up studies is required for its reliable application in the clinical management of individual patients.


Assuntos
Encéfalo/diagnóstico por imagem , Epilepsia/diagnóstico por imagem , Epilepsia/epidemiologia , Imageamento por Ressonância Magnética , Humanos , Processamento de Imagem Assistida por Computador , Vias Neurais/diagnóstico por imagem , Oxigênio/sangue
20.
EBioMedicine ; 4: 176-83, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26981581

RESUMO

Studies of posttraumatic stress disorder (PTSD) are complicated by wide variability in the intensity and duration of prior stressors in patient participants, secondary effects of chronic psychiatric illness, and a variable history of treatment with psychiatric medications. In magnetic resonance imaging (MRI) studies, patient samples have often been small, and they were not often compared to similarly stressed patients without PTSD in order to control for general stress effects. Findings from these studies have been inconsistent. The present study investigated whole-brain microstructural alterations of white matter in a large drug-naive population who survived a specific, severe traumatic event (a major 8.0-magnitude earthquake). Using diffusion tensor imaging (DTI), we explored group differences between 88 PTSD patients and 91 matched traumatized non-PTSD controls in fractional anisotropy (FA), as well as its component elements axial diffusivity (AD) and radial diffusivity (RD), and examined these findings in relation to findings from deterministic DTI tractography. Relations between white matter alterations and psychiatric symptom severity were examined. PTSD patients, relative to similarly stressed controls, showed an FA increase as well as AD and RD changes in the white matter beneath left dorsolateral prefrontal cortex and forceps major. The observation of increased FA in the PTSD group suggests that the pathophysiology of PTSD after a specific acute traumatic event is distinct from what has been reported in patients with several years duration of illness. Alterations in dorsolateral prefrontal cortex may be an important aspect of illness pathophysiology, possibly via the region's established role in fear extinction circuitry. Use-dependent myelination or other secondary compensatory changes in response to heightened demands for threat appraisal and emotion regulation may be involved.


Assuntos
Transtornos de Estresse Pós-Traumáticos/patologia , Substância Branca/patologia , Adulto , Estudos de Casos e Controles , Imagem de Tensor de Difusão , Terremotos , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/etiologia
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