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1.
Ugeskr Laeger ; 182(3)2020 Jan 13.
Artigo em Dinamarquês | MEDLINE | ID: mdl-32052730

RESUMO

In recent years, gene therapy has resurged as a potential treatment for an increasing number of medical diseases including those affecting the central nervous system (CNS), which is discussed in this review. Clinical trials have revealed promising results particularly in gene therapy for Parkinson's disease with upregulation of dopamine synthesis or downregulation of huntingtin synthesis in Huntington's disease. Gene therapy for spinal motor atrophy has received FDA approval this year. The biggest success is seen in ophthalmology, where gene therapy has been FDA/EU-approved for retinitis pigmentosa, sparking further hope of use for other CNS diseases in a near future.

2.
Clin Neurophysiol ; 131(1): 324-329, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31466846

RESUMO

OBJECTIVE: To investigate the diagnostic added value of electrical source imaging (ESI) in presurgical evaluation of patients with drug resistant focal epilepsy. METHODS: Eighty-two consecutive patients were included. We analyzed both low density (LD) and high density (HD) EEG recordings. LD ESI was done on interictal and ictal signals recorded during long-term video-EEG monitoring (LTM), with standard 25 electrodes and age-matched template head models. HD ESI was done on shorter recordings (90-120 min), with 256 electrodes, using individual head model. The multidisciplinary team made decisions first blinded to ESI (based on all other modalities) and then discussed the results of the ESI. We considered that ESI had diagnostic added value, when it provided non-redundant information that changed the patients management plan. RESULTS: ESI had diagnostic added value in 28 patients (34%). In most cases (85.7%), these changes were related to planning of the invasive recordings. In nine out of 13 patients, invasive recordings confirmed the localization. Out of eight patients in whom the ESI source was resected, six became seizure-free. CONCLUSIONS: ESI provides non-redundant information in one third of the patients undergoing presurgical evaluation. SIGNIFICANCE: This study provides evidence for the diagnostic added value of ESI in presurgical evaluation.

3.
Sci Rep ; 9(1): 19393, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31852985

RESUMO

In epilepsy patients, drug-resistant seizures often originate in one of the temporal lobes. In selected cases, when certain requirements are met, this area is surgically resected for therapeutic reasons. We kept the resected tissue slices alive in vitro for 48 h to create a platform for testing a novel treatment strategy based on neuropeptide Y (NPY) against drug-resistant epilepsy. We demonstrate that NPY exerts a significant inhibitory effect on epileptiform activity, recorded with whole-cell patch-clamp, in human hippocampal dentate gyrus. Application of NPY reduced overall number of paroxysmal depolarising shifts and action potentials. This effect was mediated by Y2 receptors, since application of selective Y2-receptor antagonist blocked the effect of NPY. This proof-of-concept finding is an important translational milestone for validating NPY-based gene therapy for targeting focal drug-resistant epilepsies, and increasing the prospects for positive outcome in potential clinical trials.

4.
Ugeskr Laeger ; 181(20)2019 May 13.
Artigo em Dinamarquês | MEDLINE | ID: mdl-31124449

RESUMO

In this review, we present evidence of treatment effect with deep brain stimulation (DBS) in patients with isolated forms of dystonia with generalised-, segmental- and focal phenotypes as well as tardive dystonia and dyskinetic cerebral palsy. Dystonia is a heterogeneous movement disorder, which can be disabling and difficult to treat. Patients with dystonia, who do not experience relief with medication and botulinum toxin, may be candidates for DBS.

5.
Neurology ; 92(6): e576-e586, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30610090

RESUMO

OBJECTIVE: To determine the diagnostic accuracy and clinical utility of electromagnetic source imaging (EMSI) in presurgical evaluation of patients with epilepsy. METHODS: We prospectively recorded magnetoencephalography (MEG) simultaneously with EEG and performed EMSI, comprising electric source imaging, magnetic source imaging, and analysis of combined MEG-EEG datasets, using 2 different software packages. As reference standard for irritative zone (IZ) and seizure onset zone (SOZ), we used intracranial recordings and for localization accuracy, outcome 1 year after operation. RESULTS: We included 141 consecutive patients. EMSI showed localized epileptiform discharges in 94 patients (67%). Most of the epileptiform discharge clusters (72%) were identified by both modalities, 15% only by EEG, and 14% only by MEG. Agreement was substantial between inverse solutions and moderate between software packages. EMSI provided new information that changed the management plan in 34% of the patients, and these changes were useful in 80%. Depending on the method, EMSI had a concordance of 53% to 89% with IZ and 35% to 73% with SOZ. Localization accuracy of EMSI was between 44% and 57%, which was not significantly different from MRI (49%-76%) and PET (54%-85%). Combined EMSI achieved significantly higher odds ratio compared to electric source imaging and magnetic source imaging. CONCLUSION: EMSI has accuracy similar to established imaging methods and provides clinically useful, new information in 34% of the patients. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that EMSI had a concordance of 53%-89% and 35%-73% (depending on analysis) for the localization of epileptic focus as compared with intracranial recordings-IZ and SOZ, respectively.


Assuntos
Epilepsia/diagnóstico por imagem , Adolescente , Adulto , Idoso , Criança , Eletroencefalografia , Epilepsia/fisiopatologia , Epilepsia/cirurgia , Feminino , Humanos , Imagem por Ressonância Magnética , Magnetoencefalografia , Masculino , Pessoa de Meia-Idade , Neuroimagem , Procedimentos Neurocirúrgicos , Tomografia por Emissão de Pósitrons , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
6.
Clin Neurophysiol ; 129(11): 2403-2410, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30278389

RESUMO

OBJECTIVE: To evaluate the accuracy of automated EEG source imaging (ESI) in localizing epileptogenic zone. METHODS: Long-term EEG, recorded with the standard 25-electrode array of the IFCN, from 41 consecutive patients with focal epilepsy who underwent resective surgery, were analyzed blinded to the surgical outcome. The automated analysis comprised spike-detection, clustering and source imaging at the half-rising time and at the peak of each spike-cluster, using individual head-models with six tissue-layers and a distributed source model (sLORETA). The fully automated approach presented ESI of the cluster with the highest number of spikes, at the half-rising time. In addition, a physician involved in the presurgical evaluation of the patients, evaluated the automated ESI results (up to four clusters per patient) in clinical context and selected the dominant cluster and the analysis time-point (semi-automated approach). The reference standard was location of the resected area and outcome one year after operation. RESULTS: Accuracy was 61% (95% CI: 45-76%) for the fully automated approach and 78% (95% CI: 62-89%) for the semi-automated approach. CONCLUSION: Automated ESI has an accuracy similar to previously reported neuroimaging methods. SIGNIFICANCE: Automated ESI will contribute to increased utilization of source imaging in the presurgical evaluation of patients with epilepsy.


Assuntos
Automação/métodos , Eletroencefalografia/métodos , Epilepsia/diagnóstico , Adolescente , Adulto , Automação/normas , Criança , Eletroencefalografia/normas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
7.
Ugeskr Laeger ; 180(13)2018 03 26.
Artigo em Dinamarquês | MEDLINE | ID: mdl-29587957

RESUMO

Surgery is the only treatment option with the potential to cure epilepsy. This review is a description of the multidisciplinary and multimodal presurgical evaluation process and the outcome of the Danish epilepsy surgery programme. The outcome aligns with international results and serious complications to surgery are very rare. The annual number of operations per capita compares to neighbouring countries and is equally distributed across Denmark. In accordance with international recommendations, Danish drug-resistant patients should be referred to epilepsy surgery evaluation at an early stage of the disease.


Assuntos
Epilepsia/cirurgia , Procedimentos Neurocirúrgicos/métodos , Procedimentos Clínicos , Dinamarca , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/cirurgia , Eletroencefalografia , Epilepsia/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética , Testes Neuropsicológicos , Procedimentos Neurocirúrgicos/efeitos adversos , Seleção de Pacientes , Tomografia por Emissão de Pósitrons , Complicações Pós-Operatórias , Cuidados Pré-Operatórios , Tomografia Computadorizada de Emissão de Fóton Único
8.
Seizure ; 54: 1-6, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29172092

RESUMO

PURPOSE: To determine visual field defects (VFDs) using methods of varying complexity and compare results with subjective symptoms in a population of newly operated temporal lobe epilepsy patients. METHODS: Forty patients were included in the study. Two patients failed to perform VFD testing. Humphrey Field Analyzer (HFA) perimetry was used as the gold standard test to detect VFDs. All patients performed a web-based visual field test called Damato Multifixation Campimetry Online (DMCO). A bedside confrontation visual field examination ad modum Donders was extracted from the medical records in 27/38 patients. All participants had a consultation by an ophthalmologist. A questionnaire described the subjective complaints. REULTS: A VFD in the upper quadrant was demonstrated with HFA in 29 (76%) of the 38 patients after surgery. In 27 patients tested ad modum Donders, the sensitivity of detecting a VFD was 13%. Eight patients (21%) had a severe VFD similar to a quadrant anopia, thus, questioning their permission to drive a car. In this group of patients, a VFD was demonstrated in one of five (sensitivity=20%) ad modum Donders and in seven of eight (sensitivity=88%) with DMCO. Subjective symptoms were only reported by 28% of the patients with a VFD and in two of eight (sensitivity=25%) with a severe VFD. Most patients (86%) considered VFD information mandatory. CONCLUSION: VFD continue to be a frequent adverse event after epilepsy surgery in the medial temporal lobe and may affect the permission to drive a car in at least one in five patients. Subjective symptoms and bedside visual field testing ad modum Donders are not sensitive to detect even a severe VFD. Newly developed web-based visual field test methods appear sensitive to detect a severe VFD but perimetry remains the golden standard for determining if visual standards for driving is fulfilled. Patients consider VFD information as mandatory.


Assuntos
Procedimentos Neurocirúrgicos/efeitos adversos , Transtornos da Percepção/etiologia , Complicações Pós-Operatórias/fisiopatologia , Lobo Temporal/cirurgia , Campos Visuais/fisiologia , Adolescente , Adulto , Dinamarca , Epilepsia/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Campo Visual , Adulto Jovem
9.
Epilepsy Res ; 133: 41-45, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28414967

RESUMO

Patients with medically refractory epilepsy may benefit from resective epilepsy surgery. However even the best centers experience surgical failures. It is therefore important to find techniques that may aid in neurosurgical planning of epileptic focus resection. Recordings of electrical brain activity with EEG during seizures reveal abnormal cortical hypersynchronization. Between seizures the EEG often shows interictal depolarizing phenomena such as spikes reflecting an irritable focus of the brain. In the present study we investigated the effect of intravenous remifentanil on the spike activity in the temporal neocortex and hippocampus. We examined 65 patients with mesial temporal lobe epilepsy during surgery, prior to resection. We used a 20-lead grid on the cortex and a 4-lead strip in the lateral ventricle on the hippocampus. At least two 3-min periods of ECoG were recorded - before and after remifentanil injection. In a number of patients we examined the effect of repeated injections in order to estimate the dose-response curve. We describe a significant effect of remifentanil on the average spike activity with an increment from 16 spikes per minute at baseline to 36 spikes per minute after remifentanil injection (p<0.0001). The increase in spike activity was typically seen after 40-50s. When mu-receptors were antagonized with a preceding injection of naloxone, spike activity increased 25% in response to remifentanil as opposed to 80% when remifentanil was preceded by placebo. In only seven out of 59 patients did the injection of remifentanil change the topographic location of the spike focus. Typically administration of remifentanil led to a focus of increased spike count. Activity in other areas was suppressed making the focus stand out from the background. Our observation that remifentanil potentiates spike activity is in agreement with previous findings from smaller studies. Furthermore, we were able to describe the pharmacodynamics of the remifentanil effect on spike activity. Peri-operative provocation with remifentanil may play a future role in guiding neurosurgical intervention during epilepsy resection surgery.


Assuntos
Analgésicos Opioides/uso terapêutico , Ondas Encefálicas/efeitos dos fármacos , Epilepsia do Lobo Temporal/fisiopatologia , Piperidinas/uso terapêutico , Adolescente , Adulto , Mapeamento Encefálico , Criança , Pré-Escolar , Relação Dose-Resposta a Droga , Eletroencefalografia , Epilepsia do Lobo Temporal/cirurgia , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Remifentanil , Estudos Retrospectivos , Adulto Jovem
10.
J Cereb Blood Flow Metab ; 37(2): 425-434, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26825776

RESUMO

Positron emission tomography (PET) can, when used with appropriate radioligands, non-invasively generate temporal and spatial information about acute changes in brain neurotransmitter systems. We for the first time evaluate the novel 5-HT2A receptor agonist PET radioligand, [11C]Cimbi-36, for its sensitivity to detect changes in endogenous cerebral 5-HT levels, as induced by different pharmacological challenges. To enable a direct translation of PET imaging data to changes in brain 5-HT levels, we calibrated the [11C]Cimbi-36 PET signal in the pig brain by simultaneous measurements of extracellular 5-HT levels with microdialysis and [11C]Cimbi-36 PET after various acute interventions (saline, citalopram, citalopram + pindolol, fenfluramine). In a subset of pigs, para-chlorophenylalanine pretreatment was given to deplete cerebral 5-HT. The interventions increased the cerebral extracellular 5-HT levels to 2-11 times baseline, with fenfluramine being the most potent pharmacological enhancer of 5-HT release, and induced a varying degree of decline in [11C]Cimbi-36 binding in the brain, consistent with the occupancy competition model. The observed correlation between changes in the extracellular 5-HT level in the pig brain and the 5-HT2A receptor occupancy indicates that [11C]Cimbi-36 binding is sensitive to changes in endogenous 5-HT levels, although only detectable with PET when the 5-HT release is sufficiently high.


Assuntos
Benzilaminas/metabolismo , Encéfalo/metabolismo , Fenetilaminas/metabolismo , Tomografia por Emissão de Pósitrons , Receptor 5-HT2A de Serotonina/metabolismo , Agonistas do Receptor 5-HT2 de Serotonina/metabolismo , Serotonina/metabolismo , Animais , Benzilaminas/análise , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Radioisótopos de Carbono/análise , Radioisótopos de Carbono/metabolismo , Feminino , Fenfluramina/farmacologia , Fenetilaminas/análise , Tomografia por Emissão de Pósitrons/métodos , Receptor 5-HT2A de Serotonina/análise , Agonistas do Receptor 5-HT2 de Serotonina/análise , Serotoninérgicos/farmacologia , Suínos
11.
Sci Rep ; 6: 24818, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27098488

RESUMO

Optogenetics is one of the most powerful tools in neuroscience, allowing for selective control of specific neuronal populations in the brain of experimental animals, including mammals. We report, for the first time, the application of optogenetic tools to human brain tissue providing a proof-of-concept for the use of optogenetics in neuromodulation of human cortical and hippocampal neurons as a possible tool to explore network mechanisms and develop future therapeutic strategies.


Assuntos
Encéfalo/citologia , Encéfalo/fisiologia , Neurônios/fisiologia , Optogenética , Channelrhodopsins , Potenciais Evocados/efeitos da radiação , Antagonistas GABAérgicos/farmacologia , Expressão Gênica , Ácido Glutâmico/metabolismo , Humanos , Luz , Receptores de GABA/metabolismo , Técnicas de Cultura de Tecidos
12.
Acta Neurochir (Wien) ; 157(8): 1437-40; discussion 1440, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26148905

RESUMO

BACKGROUND: Frame-based stereotactic procedures are the gold standard because of their superior stereotactic accuracy. The procedure used to be in multiple steps and was especially cumbersome and hazardous in intubated patients. A single-step procedure using intraoperative CT was created to optimize the procedures. METHODS: A combined fixation and low profile frame holder was designed for the operating table, allowing positioning for the scanning procedure immediately followed by the surgical biopsy procedure with the same positioning and head fixation. For placement of depth electrodes immediate CT control of positioning was feasible. RESULTS: In the first 8 months the procedure was successfully used 65 times including 8 times in pediatric cases. The procedure duration in awake patients was on average 81 min (range 33 to 202) and in intubated patients (children) on average 89 min (median 89, 78-100). DISCUSSION: This study demonstrates that frame-based stereotactic procedures in all brain locations are a feasible and practical technique with improved workflow and added patient safety and comfort.


Assuntos
Técnicas Estereotáxicas/instrumentação , Adulto , Criança , Eletrodos Implantados , Humanos , Posicionamento do Paciente/instrumentação , Posicionamento do Paciente/métodos
13.
J Neurosci ; 35(26): 9622-31, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-26134645

RESUMO

Development of novel disease-modifying treatment strategies for neurological disorders, which at present have no cure, represents a major challenge for today's neurology. Translation of findings from animal models to humans represents an unresolved gap in most of the preclinical studies. Gene therapy is an evolving innovative approach that may prove useful for clinical applications. In animal models of temporal lobe epilepsy (TLE), gene therapy treatments based on viral vectors encoding NPY or galanin have been shown to effectively suppress seizures. However, how this translates to human TLE remains unknown. A unique possibility to validate these animal studies is provided by a surgical therapeutic approach, whereby resected epileptic tissue from temporal lobes of pharmacoresistant patients are available for neurophysiological studies in vitro. To test whether NPY and galanin have antiepileptic actions in human epileptic tissue as well, we applied these neuropeptides directly to human hippocampal slices in vitro. NPY strongly decreased stimulation-induced EPSPs in dentate gyrus and CA1 (up to 30 and 55%, respectively) via Y2 receptors, while galanin had no significant effect. Receptor autoradiographic binding revealed the presence of both NPY and galanin receptors, while functional receptor binding was only detected for NPY, suggesting that galanin receptor signaling may be impaired. These results underline the importance of validating findings from animal studies in human brain tissue, and advocate for NPY as a more appropriate candidate than galanin for future gene therapy trials in pharmacoresistant TLE patients.


Assuntos
Epilepsia/patologia , Galanina/farmacologia , Hipocampo/efeitos dos fármacos , Neuropeptídeo Y/farmacologia , Sinapses/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Adolescente , Adulto , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Feminino , Guanosina 5'-O-(3-Tiotrifosfato)/farmacocinética , Hipocampo/patologia , Humanos , Técnicas In Vitro , Masculino , Potenciais da Membrana/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos , Pessoa de Meia-Idade , Técnicas de Patch-Clamp , Ensaio Radioligante , Receptores de Galanina/metabolismo , Receptores de Neuropeptídeo Y/metabolismo , Isótopos de Enxofre/farmacocinética , Adulto Jovem
15.
J Neurosurg ; 119(6): 1537-45, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24116723

RESUMO

OBJECT: The authors' aim was to compare the subthalamic nucleus (STN) with the globus pallidus internus (GPi) as a stimulation target for deep brain stimulation (DBS) for medically refractory dystonia. METHODS: In a prospective double-blind crossover study, electrodes were bilaterally implanted in the STN and GPi of 12 patients with focal, multifocal, or generalized dystonia. Each patient was randomly selected to undergo initial bilateral stimulation of either the STN or the GPi for 6 months, followed by bilateral stimulation of the other nucleus for another 6 months. Preoperative and postoperative ratings were assessed by using the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) and video recordings. Quality of life was evaluated by using questionnaires (36-item Short Form Health Survey). Supplemental Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) scores were assessed for patients with focal dystonia (torticollis) by examining the video recordings. RESULTS: On average for all patients, DBS improved the BFMDRS movement scores (p < 0.05) and quality of life physical scores (p < 0.01). After stimulation of the STN, the mean 6-month improvement in BFMDRS movement score was 13.8 points; after stimulation of the GPi, this improvement was 9.1 points (p = 0.08). Quality of life did not differ significantly regardless of which nucleus was stimulated. All 12 patients accepted 6 months of stimulation of the STN, but only 7 accepted 6 months of stimulation of the GPi. Among those who rejected stimulation of the GPi, 3 accepted concomitant stimulation of both the STN and GPi for 6 months, resulting in improved quality of life physical and mental scores and BFMDRS movement scores. Among the 4 patients who were rated according to TWSTRS, after 6 months of stimulation of both the STN and GPi, TWSTRS scores improved by 4.7% after stimulation of the GPi and 50.8% after stimulation of the STN (p = 0.08). CONCLUSIONS: The STN seems to be a well-accepted, safe, and promising stimulation target in the treatment of dystonia, but further studies are necessary before the optimal target can be concluded. Simultaneous stimulation of the STN and GPi should be further investigated. Clinical trial registration no.: KF 01-110/01 (Committees on Biomedical Research Ethics of the Capital Region of Denmark).


Assuntos
Estimulação Encefálica Profunda/métodos , Distonia/terapia , Globo Pálido/fisiopatologia , Núcleo Subtalâmico/fisiopatologia , Adulto , Idade de Início , Idoso , Estudos Cross-Over , Estimulação Encefálica Profunda/instrumentação , Método Duplo-Cego , Distonia/fisiopatologia , Distonia/cirurgia , Eletrodos Implantados/estatística & dados numéricos , Globo Pálido/cirurgia , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Qualidade de Vida , Índice de Gravidade de Doença , Núcleo Subtalâmico/cirurgia , Torcicolo/fisiopatologia , Torcicolo/terapia , Resultado do Tratamento
16.
Epilepsia ; 54(10): 1743-52, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23944234

RESUMO

PURPOSE: Although precise identification of the seizure-onset zone is an essential element of presurgical evaluation, source localization of ictal electroencephalography (EEG) signals has received little attention. The aim of our study was to estimate the accuracy of source localization of rhythmic ictal EEG activity using a distributed source model. METHODS: Source localization of rhythmic ictal scalp EEG activity was performed in 42 consecutive cases fulfilling inclusion criteria. The study was designed according to recommendations for studies on diagnostic accuracy (STARD). The initial ictal EEG signals were selected using a standardized method, based on frequency analysis and voltage distribution of the ictal activity. A distributed source model-local autoregressive average (LAURA)-was used for the source localization. Sensitivity, specificity, and measurement of agreement (kappa) were determined based on the reference standard-the consensus conclusion of the multidisciplinary epilepsy surgery team. Predictive values were calculated from the surgical outcome of the operated patients. To estimate the clinical value of the ictal source analysis, we compared the likelihood ratios of concordant and discordant results. Source localization was performed blinded to the clinical data, and before the surgical decision. KEY FINDINGS: Reference standard was available for 33 patients. The ictal source localization had a sensitivity of 70% and a specificity of 76%. The mean measurement of agreement (kappa) was 0.61, corresponding to substantial agreement (95% confidence interval (CI) 0.38-0.84). Twenty patients underwent resective surgery. The positive predictive value (PPV) for seizure freedom was 92% and the negative predictive value (NPV) was 43%. The likelihood ratio was nine times higher for the concordant results, as compared with the discordant ones. SIGNIFICANCE: Source localization of rhythmic ictal activity using a distributed source model (LAURA) for the ictal EEG signals selected with a standardized method is feasible in clinical practice and has a good diagnostic accuracy. Our findings encourage clinical neurophysiologists assessing ictal EEGs to include this method in their armamentarium.


Assuntos
Eletroencefalografia , Convulsões/diagnóstico , Adolescente , Adulto , Idoso , Encéfalo/fisiopatologia , Criança , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Padrões de Referência , Convulsões/fisiopatologia , Sensibilidade e Especificidade , Adulto Jovem
17.
Clin Neurophysiol ; 124(8): 1570-7, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23578564

RESUMO

OBJECTIVE: To estimate the area of cortex affecting the extracranial EEG signal. METHODS: The coherence between intra- and extracranial EEG channels were evaluated on at least 10 min of spontaneous, awake data from seven patients admitted for epilepsy surgery work up. RESULTS: Cortical electrodes showed significant extracranial coherent signals in an area of approximately 150 cm(2) although the field of vision was probably only 31 cm(2) based on spatial averaging of intracranial channels taking into account the influence of the craniotomy and the silastic membrane of intracranial grids. Selecting the best cortical channels, it was possible to increase the coherence values compared to the single intracranial channel with highest coherence. The coherence seemed to increase linearly with an accumulation area up to 31 cm(2), where 50% of the maximal coherence was obtained accumulating from only 2 cm(2) (corresponding to one channel), and 75% when accumulating from 16 cm(2). CONCLUSION: The skull is an all frequency spatial averager but dominantly high frequency signal attenuator. SIGNIFICANCE: An empirical assessment of the actual area of cerebral sources generating the extracranial EEG provides better opportunities for clinical electroencephalographers to determine the location of origin of particular patterns in the EEG.


Assuntos
Córtex Cerebral/fisiopatologia , Epilepsia/fisiopatologia , Espaço Subdural/fisiopatologia , Adolescente , Idoso , Mapeamento Encefálico , Eletrodos , Eletroencefalografia , Feminino , Humanos , Masculino
18.
Int J Radiat Oncol Biol Phys ; 77(2): 542-7, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19796884

RESUMO

PURPOSE: Primarily, gamma knife centers are predominant in publishing results on arteriovenous malformations (AVM) treatments including reports on risk profile. However, many patients are treated using a linear accelerator-most of these at smaller centers. Because this setting is different from a large gamma knife center, the risk profile at Linac departments could be different from the reported experience. Prescribed radiation doses are dependent on AVM volume. This study details results from a medium sized Linac department center focusing on risk profiles. METHOD AND MATERIALS: A database was searched for all patients with AVMs. We included 50 consecutive patients with a minimum of 24 months follow-up (24-51 months). RESULTS: AVM occlusion was verified in 78% of patients (39/50). AVM occlusion without new deficits (excellent outcome) was obtained in 44%. Good or fair outcome (AVM occlusion with mild or moderate new deficits) was seen in 30%. Severe complications after AVM occlusion occurred in 4% with a median interval of 15 months after treatment (range, 1-26 months). CONCLUSIONS: We applied an AVM grading score developed at the Mayo Clinic to predict probable outcome after radiosurgery in a large patient population treated with Gamma knife. A cutoff above and below a score of 1.5 could not discriminate between the likelihood of having an excellent outcome (approximately 45%). The chance of having an excellent or good outcome was slightly higher in patients with an AVM score below 1.5 (64% vs. 57%).


Assuntos
Malformações Arteriovenosas Intracranianas/cirurgia , Radiocirurgia/efeitos adversos , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Aceleradores de Partículas , Radiocirurgia/instrumentação , Radiocirurgia/métodos , Dosagem Radioterapêutica , Fatores de Risco , Resultado do Tratamento , Adulto Jovem
19.
Ugeskr Laeger ; 168(42): 3627-9, 2006 Oct 16.
Artigo em Dinamarquês | MEDLINE | ID: mdl-17069727

RESUMO

INTRODUCTION: This study was performed to identify the substances used in deliberate self-poisoning and to investigate the epidemiological characteristics of these cases, with the goal of improving prevention of suicides. MATERIALS AND METHODS: The material is made up of 121 cases of deliberate self-poisoning examined at the Institute of Forensic Medicine, University of Aarhus, during the years 1994-2003. The cases were subjected to a forensic autopsy and a toxicological screening for alcohol, drugs, carbon monoxide, cyanide and pesticides. RESULTS: This material included only 12% of the cases of deliberate self-poisoning in the area serviced by the Institute. 70% were caused by legal drugs and 17% by carbon monoxide. A total of 52 different substances were found. In one third of the cases, two or more substances were found in a lethal concentration. Analgesics and antidepressants were the most common of these. The wide range of substances used was subject to change during the period of investigation. In addition, 40 different substances in therapeutic or only slightly increased concentrations were found. In most cases, the deceased was unemployed, living alone, suffering from a psychiatric disease and addicted to legal or illegal drugs or alcohol. In half the cases, there had been a previous suicide attempt. CONCLUSION: It is recommended that only small amounts of drugs be prescribed to persons in danger of committing suicide, as identified by the above-mentioned characteristics.


Assuntos
Envenenamento/epidemiologia , Suicídio/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Analgésicos/envenenamento , Antidepressivos/envenenamento , Autopsia , Intoxicação por Monóxido de Carbono/epidemiologia , Intoxicação por Monóxido de Carbono/prevenção & controle , Dinamarca/epidemiologia , Prescrições de Medicamentos , Feminino , Medicina Legal , Humanos , Hipnóticos e Sedativos/envenenamento , Masculino , Pessoa de Meia-Idade , Envenenamento/prevenção & controle , Estudos Retrospectivos , Fatores Socioeconômicos , Suicídio/prevenção & controle
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