No description available.

A epilepsia do lobo temporal (ELT), além de ser o tipo de epilepsia focal mais comum, também é a que tem maior refratariedade à farmacoterapia, correspondendo à 30% dos casos. Se não tratada pode levar à piora da qualidade de vida, déficits cognitivos e risco de morte (ENGEL, 1998). O tratamento padrão para ELT farmacorresistente é a remoção cirúrgica das estruturas envolvidas (ENGEL, 1996), com taxas de cura que podem chegar a 80% (ENGEL, 2001a). Os benefícios da cirurgia são: diminuição da frequência e severidade das crises, diminuição da mortalidade, melhores índices de qualidade de vida. Recomenda-se que pacientes com ELT farmacorresistentes sejam referenciados a um centro de cirurgia de epilepsia para avaliar a possibilidade de intervenção cirúrgica (ENGEL et al., 2003). Em nosso estudo, avaliamos 621 pacientes com epilepsia mesial do lobo temporal, com confirmação histopatológica de esclerose hipocampal, que realizaram ressecção do lobo temporal no Centro de Cirurgia de Epilepsia de Ribeirão Preto (CIREP) entre os anos de 1994 até 2011. Avaliamos os principais fatores preditores que influenciam no sucesso cirúrgico relacionados ao controle das crises epilépticas, através de um estudo longitudinal e retrospectivo. Realizamos o acompanhamento clínico desses pacientes por até 23 anos, com média de 11,6 anos (± 5,3) e encontramos que 73,6% dos pacientes ficaram livres de crises com alteração da consciência (Engel I) e 84,7% tiveram um bom prognóstico cirúrgico (Engel I + II). Esse prognóstico foi relativamente mantido ao longo do tempo em 65 % dos pacientes, após 20 a 23 anos da cirurgia. Encontramos que a história de crise febril foi um fator de bom prognóstico, enquanto que a aura dismnésica e olfatória foram fatores de mau prognóstico. Em relação ao tipo de técnica cirúrgica, a lobectomia temporal anteromesial (com ressecção do polo temporal), obteve significativo melhor prognóstico (78,6% Engel I) em relação à cirurgia que poupa o polo temporal (67,2% Engel I), p=0,002*, sugerindo que as conexões neurais envolvidas na zona epileptogênica podem estar além das estruturas mesiais. Concluímos que a cirurgia para epilepsia é um procedimento seguro, com baixos índices de complicações pós-operatórias e bons resultados em longo prazo. / Temporal lobe epilepsy (TLE) is the most common type of focal epilepsy and the one that has greater refractoriness to pharmacotherapy, corresponding to 30% of the cases. If untreated, it can lead to worsening of quality of life, cognitive deficits and risk of death (ENGEL, 1998). The standard treatment for medically refractory TLE is the surgical removal of the structures involved (ENGEL, 1996), with good outcomes rates that can reach to 80% (ENGEL, 2001a). The benefits of the surgery are: decrease in frequency and severity of seizures, decrease in mortality, better indexes of quality of life and higher rates of return to school and work. It is recommended that medically refractory TLE patients should be referred to an epilepsy surgery center to evaluate the possibility of surgical intervention (ENGEL et al., 2003). In our study, we evaluated 621 patients with mesial temporal lobe epilepsy secondary to hippocampal sclerosis (MTLE-HS), who underwent a temporal lobectomy at our epilepsy surgery center (CIREP) between the years 1994 to 2011. We evaluated the main predictive factors that influence the surgical outcome, through a longitudinal and retrospective study. We performed the clinical follow-up for up to 23 years and the mean follow-up was 11,6 years (± 5,3). We found that 73,6 % of the patients were free of disabling seizures and 84,7% had a good surgical outcome (Engel I + II). This prognosis was relatively maintained over the time in 65% of patients after 20 to 23 years of surgery. We found that history of febrile seizure was a good prognostic factor, whereas the dysmnesic and olfactory aura were factors of poor outcome. Regarding the type of surgical technique, the anteromesial temporal lobe resection obtained significant better outcomes (78,6% Engel I) in relation to the surgery who preserve the temporal pole (67,2% Engel I), p value = 0,002*, suggesting that the neuronal networks involved in the epileptogenic zone may be beyond mesial structures. We conclude that epilepsy surgery is a safe procedure, with low rates of postoperative complications and good long-term results.

Pacientes com epilepsia farmacorresistente, frequentemente, possuem lesões extrahipocampais como etiologia. Muitas vezes, estes pacientes se beneficiam de lesionectomias para redução da ocorrência de crises epilépticas. Para que possam se submeter a este procedimento, atualmente é necessário o uso tanto da videoeletroencefalografia prolongada (VEEG) quanto da imagem de ressonância magnética do encéfalo (IRM) para delimitação apurada da zona epileptogênica, local que deve ser ressecado para controle das crises. No presente trabalho, foi estudada a acurácia diagnóstica da VEEG e da IRM na determinação da zona epileptogênica de pacientes com displasia cortical focal. Comparou-se os locais de ocorrência da zona de início ictal (VEEG) e da lesão epileptogênica (IRM) se concordantes ou discordantes com o local da cirurgia. Foram revisados os prontuários médicos de 209 pacientes, sendo o padrão de referência (local da cirurgia) e tempo de acompanhamento pós-operatório superior a 12 meses disponíveis em 43 pacientes. A VEEG apresentou sensibilidade de 85,7% (IC 95% 62,6-96,2) e especificidade de 41,1% (IC 95% 19,4-66,5), com valor preditivo positivo de 64,2% (IC 95% 44,1-80,6) e valor preditivo negativo de 70% (IC 95% 35,3-91,9). A IRM apresentou sensibilidade de 91,6% (IC 95% 71,5-98,5) e especificidade de 36,8% (IC 95% 17,2-61,3), com valor preditivo positivo de 64,7% (IC 95% 46,4-79,6) e valor preditivo negativo de 77,7% (IC 95% 40,1-96). As diferenças de sensibilidade e especificidade, áreas sob as curvas ROC e os índices de Youden não foram significativas. A concordância dos resultados da VEEG e da IRM foi moderada (k=0,599; p<0,01; IC 95% 0,468-0,730). / Patients with drug-resistant epilepsy frequently have extrahippocampal lesions as etiology. A large proportion of these patients might benefit from lesionectomy for the reduction of seizures. For surgery to be undertaken, it is usually performed both long-term videoelectroencephalography monitoring (VEEG) and magnetic resonance imaging of the brain (MRI) for the precise delimitation of the epileptogenic zone, the region that must be resected for seizure control. In the present study, the diagnostic accuracy of VEEG and MRI were studied in the localization of the epileptogenic zone in patients with focal cortical dysplasia. The seizure-onset zone (VEEG) and the region of epileptogenic lesion (MRI) were compared whereas concordant or discordant regarding surgery region. Medical charts of 209 patients were reviewed, being the reference standard (surgery region) and post-surgical follow-up longer than 12 months available in 43 patients. Videoelectroencephalography has a sensitivity of 85.7% (95% CI 62.6-96.2) and specificity of 41.1% (95% CI 19.4-66.5), with positive predictive value of 64.2% (95% CI 44.1-80.6) and negative predictive value of 70% (95% CI 35.3-91.9). Magnetic resonance imaging has a sensitivity of 91.6% (95% CI 71.5-98.5) and specificity of 36.8% (95% CI 17.2-61.3), with positive predictive value of 64.7% (95% CI 46.4-79.6) and negative predictive value of 77.7% (95% CI 40.1-96). The differences of sensitivity and specificity, areas under the ROC curves and Youden\'s indexes were not significant. The concordance between the results of VEEG and MRI was moderate (k=0.599; p<0.01; 95% CI 0.468-0.730).

Recent experimental studies point to the notion that the brain is a complex dynamical system whose behaviors relating to brain functions and dysfunctions can be described by the physics of network phenomena. The brain consists of anatomical axonal connections among neurons and neuronal populations in various spatial scales. Neuronal interactions and synchrony of neuronal oscillations are central to normal brain functions. Breakdowns in interactions and modifications in synchronization behaviors are usual hallmarks of brain dysfunctions. Here, in this dissertation for PhD degree in physics, we report discoveries of brain oscillatory network activity from two separate studies. These studies investigated the large-scale brain activity during tactile perceptual decision-making and epileptic seizures. In the perceptual decision-making study, using scalp electroencephalography (EEG) recordings of brain potentials, we investigated how oscillatory activity functionally organizes different neocortical regions as a network during a tactile discrimination task. While undergoing EEG recordings, blindfolded healthy participants felt a linear three-dot array presented electromechanically, under computer control, and reported whether the central dot was offset to the left or right. Based on the current dipole modeling in the brain, we found that the source-level peak activity appeared in the left primary somatosensory cortex (SI), right lateral occipital complex (LOC), right posterior intraparietal sulcus (pIPS) and finally left dorsolateral prefrontal cortex (dlPFC) at 45, 130, 160 and 175 ms respectively. Spectral interdependency analysis showed that fine tactile discrimination is mediated by distinct but overlapping ~15 Hz beta and ~80 Hz gamma band large-scale oscillatory networks. The beta-network that included all four nodes was dominantly feedforward, similar to the propagation of peak cortical activity, implying its role in accumulating and maintaining relevant sensory information and mapping to action. The gamma-network activity, occurring in a recurrent loop linked SI, pIPS and dlPFC, likely carrying out attentional selection of task-relevant sensory signals. Behavioral measure of task performance was correlated with the network activity in both bands. In the study of epileptic seizures, we investigated high-frequency (> 50 Hz) oscillatory network activity from intracranial EEG (IEEG) recordings of patients who were the candidates for epilepsy surgery. The traditional approach of identifying brain regions for epilepsy surgery usually referred as seizure onset zones (SOZs) has not always produced clarity on SOZs. Here, we investigated directed network activity in the frequency domain and found that the high frequency (>80 Hz) network activities occur before the onset of any visible ictal activity, andcausal relationships involve the recording electrodes where clinically identifiable seizures later develop. These findings suggest that high-frequency network activities and their causal relationships can assist in precise delineation of SOZs for surgical resection.

Pacientes com epilepsia farmacorresistente, frequentemente, possuem lesões extrahipocampais como etiologia. Muitas vezes, estes pacientes se beneficiam de lesionectomias para redução da ocorrência de crises epilépticas. Para que possam se submeter a este procedimento, atualmente é necessário o uso tanto da videoeletroencefalografia prolongada (VEEG) quanto da imagem de ressonância magnética do encéfalo (IRM) para delimitação apurada da zona epileptogênica, local que deve ser ressecado para controle das crises. No presente trabalho, foi estudada a acurácia diagnóstica da VEEG e da IRM na determinação da zona epileptogênica de pacientes com displasia cortical focal. Comparou-se os locais de ocorrência da zona de início ictal (VEEG) e da lesão epileptogênica (IRM) se concordantes ou discordantes com o local da cirurgia. Foram revisados os prontuários médicos de 209 pacientes, sendo o padrão de referência (local da cirurgia) e tempo de acompanhamento pós-operatório superior a 12 meses disponíveis em 43 pacientes. A VEEG apresentou sensibilidade de 85,7% (IC 95% 62,6-96,2) e especificidade de 41,1% (IC 95% 19,4-66,5), com valor preditivo positivo de 64,2% (IC 95% 44,1-80,6) e valor preditivo negativo de 70% (IC 95% 35,3-91,9). A IRM apresentou sensibilidade de 91,6% (IC 95% 71,5-98,5) e especificidade de 36,8% (IC 95% 17,2-61,3), com valor preditivo positivo de 64,7% (IC 95% 46,4-79,6) e valor preditivo negativo de 77,7% (IC 95% 40,1-96). As diferenças de sensibilidade e especificidade, áreas sob as curvas ROC e os índices de Youden não foram significativas. A concordância dos resultados da VEEG e da IRM foi moderada (k=0,599; p<0,01; IC 95% 0,468-0,730). / Patients with drug-resistant epilepsy frequently have extrahippocampal lesions as etiology. A large proportion of these patients might benefit from lesionectomy for the reduction of seizures. For surgery to be undertaken, it is usually performed both long-term videoelectroencephalography monitoring (VEEG) and magnetic resonance imaging of the brain (MRI) for the precise delimitation of the epileptogenic zone, the region that must be resected for seizure control. In the present study, the diagnostic accuracy of VEEG and MRI were studied in the localization of the epileptogenic zone in patients with focal cortical dysplasia. The seizure-onset zone (VEEG) and the region of epileptogenic lesion (MRI) were compared whereas concordant or discordant regarding surgery region. Medical charts of 209 patients were reviewed, being the reference standard (surgery region) and post-surgical follow-up longer than 12 months available in 43 patients. Videoelectroencephalography has a sensitivity of 85.7% (95% CI 62.6-96.2) and specificity of 41.1% (95% CI 19.4-66.5), with positive predictive value of 64.2% (95% CI 44.1-80.6) and negative predictive value of 70% (95% CI 35.3-91.9). Magnetic resonance imaging has a sensitivity of 91.6% (95% CI 71.5-98.5) and specificity of 36.8% (95% CI 17.2-61.3), with positive predictive value of 64.7% (95% CI 46.4-79.6) and negative predictive value of 77.7% (95% CI 40.1-96). The differences of sensitivity and specificity, areas under the ROC curves and Youden\'s indexes were not significant. The concordance between the results of VEEG and MRI was moderate (k=0.599; p<0.01; 95% CI 0.468-0.730).

In its general section, the thesis 'Rehabilitation of Pediatric Patients after Epilepsy Surgery with Postoperative Motor Deficits' discusses epilepsy, treatment of intractable epilepsy and epilepsy surgery. Furthermore, a chapter on possible complications of epilepsy surgery in relation to the locomotor apparatus is included in the general section. The special section deals with rehabilitation in neurology, selected physiotherapy concepts and the relationship between epilepsy and movement activity. The aim of this thesis is to assess the effectiveness of the chosen rehabilitation procedure in five pediatric patients with post-operative motor deficiency. The Gross Motor Function Measure - 88, the Barthel Index and the Box and Blocks Test were used for objective motor assessment.

Plusieurs études de simulation in vitro et in vivo ont été réalisées au cours des dernières décennies afin de clarifier les interrelations des sources corticales avec leurs corrélats électrophysiologiques enregistrés sur l’EEG invasif et l’EEG de scalp. L’amplitude des potentiels corticaux, l’étendue de l’aire corticale impliquée par la décharge, de même que la localisation et la géométrie de la source corticale sont des facteurs indépendants qui modulent l’observabilité et la contribution de ces sources sur l’EEG de surface. L’enregistrement simultané et multi-échelle de l’EEG de scalp et intra-crânien (avec des électrodes sous-durales ou profondes) durant l’exploration pré-chirurgicale des patients épileptiques offre une opportunité unique d’explorer cette question fondamentale. Alors que les études précédentes ont considéré essentiellement des sources néocorticales dans le contexte de l’épilepsie du lobe temporal, notre travail s’est intéressé à l’observabilité et la contribution de sources profondes temporales et frontales. Nous avons pu montrer : (1) que les sources épileptiques profondes enregistrées dans les régions temporales médianes et fronto-basales ne sont pas visibles par l’analyse visuelle de routine mais sont détectables après élimination du bruit de fond physiologique généré par les sources corticales de surface sus-jacentes ; (3) que l’amplitude des pointes enregistrées en surface est corrélée avec la surface d’activation corticale de la convexité et avec des ratios élevés d’amplitude pointes/activité de fond / Several in vitro, in vivo, and simulation studies have been performed in the past decades aiming to clarify the interrelations of cortical sources with their scalp and invasive EEG correlates. The amplitude ratio of cortical potentials to their scalp EEG correlates, the extent of the cortical area involved in the discharge, as well as the localization of the cortical source and its geometry, have been each independently linked to the recording of the cortical discharge with scalp electrodes. Simultaneous multiscale EEG recordings with scalp, subdural and depth electrodes, applied in presurgical epilepsy workup, offer an excellent opportunity to address this fundamental issue. Whereas past studies have considered predominantly neocortical sources in the context of temporal lobe epilepsy, the present work addresses deep sources, in mesial temporal and extra-temporal epilepsies. We showed that deep sources, such as those in mesial temporal or fronto-basal regions, are not visible, but are detectable in scalp EEG. Scalp EEG spikes correlate with extensive activation of the cortical convexity and high spike-to-background amplitude ratios

Introdução. As hemisferectomias são cirurgias utilizadas há décadas para se tratar epilepsias refratárias à medicação anticonvulsivante. Embora o controle das crises seja satisfatório, a morbidade, per e pós-operatória, ainda é considerada um importante fator limitante à sua utilização. Dessa maneira, compreender as complicações mais comuns do procedimento, e os fatores que as influenciam, é essencial para se estabelecer o melhor uso para a técnica. Métodos. Foram coletados dados de 30 pacientes, operados por seis cirurgiões no Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo no período entre 1980 e 2003. Foram realizadas 11 hemisferectomias com a abordagem de Rasmussen, três hemisferectomias anatômicas, nove hemisferectomias funcionais extraventriculares e sete hemisferotomias. Foram estudados cinco grupo de pacientes de acordo com a fisiopatologia da doença de base: Dezesseis pacientes eram portadores de Síndrome de Rasmussen, dois da Síndrome de Sturge-Weber, quatro de malformações corticais, dois de lesões sequelares e seis de cistos porencefálicos. Os fatores de morbidade foram avaliados dentro de rês perspectivas: 1- da doença de base; 2- da técnica utilizada; e 3- do fator humano. Resultados. Nossos dados mostraram ausência de diferença estatisticamente significativa entre as técnicas cirúrgicas empregadas nos itens: tempo cirúrgico; tempo de internação na unidade de terapia intensiva; queda da hemoglobina; volume de hemoderivados transfundidos e febre no pós-operatório. Presença de leucograma acima de 15.000 leucócitos/mm3 no pós-operatório imediato foi associada a estadias mais longas na unidade de terapia intensiva A média diária de temperatura dos pacientes, mostrou temperaturas acima de 38º C entre o terceiro e sexto dia pós-operatório. Pacientes com hemimegalencefalia apresentaram temperaturas mais elevadas quando comparados com os portadores de cistos porencefálicos. Doenças com maior manto cortical contribuíram para aumentar o tempo cirúrgico, embora o fator humano tenha sido decisivo nesse item. Ao comparar nossos achados com os da literatura, vimos que os pacientes submetidos à hemisferectomia anatômica apresentaram no pós-operatório temperaturas mais elevadas e reação inflamatória liquórica mais intensa que os submetidos a técnicas de desconexão hemisférica, no entanto, a importância desse dado necessita ser estabelecida. Conclusões: O principal fator de morbidade nas hemisferectomias é a doença de base, assim, os dados presentes na literatura, incluindo nossa casuística, não nos permite concluir que uma técnica seja superior à outra ou que as técnicas desconectivas sejam melhores que as ressectivas / Hemispherectomy has been the treatment of choice in some sorts of refractory epilepsies for decades. Although surgery results in satisfactory control of seizures, its morbidity remains a major concern. Thus, understanding most common complications, as well as the factors that contribute to it, becomes an essential step to learn the limits on technique applications. Methods. Hospital charts from 30 patients operated on by six different surgeons at the Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo from 1980 to 2003 were reviewed. Eleven functional hemispherectomies using Rasmussen approach, three anatomical hemispherectomies, nine extraventricular functional hemispherectomies, and seven hemispherotomies were included in this study. Sixteen patients presented with Rasmussen Syndrome, two Sturge-Weber Syndrome, four cortical malformations, two hemispheric lesions, and six porencephalic cysts. Morbidity was evaluated from three different perspectives 1- background disease, 2- employed technique, and 3- human factor. Results: our data presented no statistical difference among the employed techniques regarding 1- surgical time, 2- intensive care unit time, 3- per and postoperative fall of hemoglobin, 4- blood transfusion volume, and 5- postoperative axilar temperature variation. Patients that presented over 15,000 leucocytes per mm3 stayed longer at the intensive care unit, regardless of the surgical technique employed. Daily average temperatures varied around 38 degrees Celsius from the third to the sixth postoperative day. Patients with hemimegalencephaly had higher postoperative axilar temperatures when compared to those with porencephaly. Thicker cortical mantle contributed to increase surgical time, though human factor also showed to be important in this item. Comparing data from this study and the literature disclosed that patients undergoing anatomical hemispherectomies presented an inflammatory response in the cerebrospinal fluid more evident than those submitted to cerebral disconnection, although the importance of this finding is still elusive. Conclusions: The main factors of morbidity in the hemispherectomy are the background disease and patient\'s peculiarities, therefore, it is not reasonable to infer that there is a superior technique or that hemisphere disconnection is better than removal

Sabe-se que a epilepsia do lobo temporal associada à esclerose hipocampal (ELT-EH) é uma síndrome epiléptica frequente e de difícil controle medicamentoso. Além disso, esta condição acarreta em uma série de prejuízos cognitivos aos seus portadores antes e após a cirurgia para tratamento das crisesrefratárias. Alguns trabalhos mostram que o prognóstico cognitivo pode mudar dependendo da abordagem cirúrgica realizada. Dessa forma, este trabalho teve como objetivo verificar qual o papel do polo temporal no funcionamento cognitivo. Para isso, foi realizada uma análise retrospectiva dos prontuários médicos de 146 pacientes adultos com ELT-EH esquerda, destros, avaliados no Centro de Cirurgia de Epilepsia (CIREP) do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto (HCFMRP) - Universidade de São Paulo (USP). Os resultados mostraram um melhor desempenho na tarefa de nomeação por confronto visual nos pacientes que passaram por lobectomia temporal esquerda sem ressecção do polo (p=0.007). Quando realizada da análise do índicede mudança confiável (RCI) para verificar a relevância clínica dos achados, 39,4% dos pacientes que passaram pela cirurgia com ressecção do polo temporal mostraram uma piora significativa de desempenho no teste de nomeação por confronto visual no Boston Naming Test (BNT), enquanto apenas 16% dos que passaram pela cirurgia sem ressecção do polo mostraram piora significativa no mesmo teste (p=0.015). No entanto, este mesmo grupo mostrou um pior prognóstico de controle de crises quando comparado ao grupo com ressecção do polo (p=0.018). Assim, esses dadosindicam que o polo temporal pode estar envolvido em habilidades de nomeação. Nossos resultados sugerem, portanto, que a cirurgia para o tratamento das crises refratárias nos pacientes com ELT-EH esquerda poderiam considerar as diferenças individuais para decidir a melhor abordagem cirúrgica para cada paciente / It is known that the temporal lobe epilepsy (TLE) associated with hippocampal sclerosis (HS) is a frequent epileptic syndrome with difficult medication control. In addition, this condition leads to a series of cognitive impairments to patients before and after surgery for the treatment of refractory crises. Studies shown that cognitive prognosis may change depending on the surgical approach. Thus, this study aimed to verify the role of temporal pole in cognitive functions. A retrospective analysis of medical records from 146 adult patients with left-sided TLE-HS - evaluated at the Center for Epilepsy Surgery (CIREP) of the Clinical Hospital from Ribeirão Preto Medical School was performed. The results showed a higherperformance on visual confrontation namingtests - according to the Boston Naming Test (BNT) - in patients submitted to left temporal lobectomy without pole resection (p=0.007). Reliable change index (RCI)analysis, for clinical relevance,revealed that 39.4% of the patients submitted to temporal pole resectionshowed significantly worse performance on visual confrontation naming and only 16% of the patients without pole resection were significantly worse in the same test (p=0.015). However, this same group showed a worse prognosis of crisis control when compared to the group with pole resection (p=0.018). Altogether, the present study suggest that the temporal pole may be involved in naming skills. Our results suggest that surgery for left TLE-HS should be performed considering individual differences to decide the best surgical approach for each patient

No description available.