38 research outputs found
Texture analysis of magnetic resonance images of patients with juvenile myoclonic epilepsy
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Background/purpose: Juvenile myoclonic epilepsy (JME) is the most frequent subsyndrome of the idiopathic generalized epilepsies, and experimental investigations support that the thalamus is a key structure in the mechanisms of JME. Texture analysis (TA) is an image processing technique which can be used to characterize images such as MRI. Objective: The goal of this work was to investigate the thalamus of patients with JME using TA, a quantitative neuroimaging technique. Methods: Patients and controls were submitted to MRI investigation. Images were acquired in a 2-Tesla scanner. The T1 volumetric sequence was used for thalamic segmentation and extraction of texture parameters. Twenty-four patients with a diagnosis of JME and 20 healthy volunteers were investigated. Results: Texture analysis revealed differences between the right thalamus of patients and controls. Conclusions: The present investigation supports the participation of the thalamus in the disease mechanisms of JME. Texture analysis may be a useful tool in the quantitative neuroimaging investigation of the epilepsies and can be important to understand JME. (C) 2012 Elsevier Inc. All rights reserved.2712228Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Seizures and cerebral schistosomiasis
Background: Schistosoma mansoni is a parasitic trematoid worm that infects humans. Schistosomiasis is endemic in parts of South America, sub-Saharan Africa, the Middle East, and some Caribbean islands. Disorders of the liver and gastrointestinal tract are the most common clinical manifestations. The central nervous system is not usually affected. The most common neurologic manifestation is transverse myelitis. In some circumstances, the eggs of S mansoni are found in the brain, causing inflammatory reaction. Objective: To describe a young Brazilian patient with partial epileptic seizures caused by a granulomatous lesion due to S mansoni. Conclusion: In endemic areas or in patients with a positive epidemiological history, schistosomiasis must be considered as a possible diagnosis of seizures, particularly when they are associated with granulomatous lesions on magnetic resonance imaging.6261008101
Correlation Between Quantitative EEG and MRI in Idiopathic Generalized Epilepsy
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The objective of this study was to investigate the relationship between the focal discharges sometimes observed in the electroencephalogram of patients with idiopathic generalized epilepsies and subtle structural magnetic resonance imaging abnormalities. The main hypothesis to be assessed is that focal discharges may arise from areas of structural abnormality which can be detected by quantitative neuroimaging Focal discharges were used for quantitative electroencephalogram source detection. Neuroimaging investigations consisted of voxel-based morphometry and region of Interest volumetry. For voxel-based morphometry, volumetric MRI were acquired and processed. The images of each patient were individually compared with a control group. Statistical analysis was used to detect differences in gray matter volumes Region of interest-based morphometry was automatically performed and used essentially to confirm voxel-based morphometry findings The localization of the focal discharges on the electroencephalogram was compared to the neuroimaging results Twenty-two patients with idiopathic generalized epilepsies were evaluated. Gray matter abnormalities were detected by voxel-based morphometry analysis in 77% of the patients. There was a good concordance between EEG source detection and voxel-based morphometry On average, the nearest voxels detected by these methods were 39 mm (mm) apart and the most statistically significant voxels were 34 mm apart. This study suggests that in some cases subtle gray matter abnormalities are associated with focal epileptiform discharges observed in the electroencephalograms of patients with idiopathic generalized epilepsies Hum Brain Mapp 31:1327-1338, 2010. (C) 2010 Wiley-Liss, Inc31913271338Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
MRI reveals structural abnormalities in patients with idiopathic generalized epilepsy
Objective: To evaluate MRI findings in a large group of patients with idiopathic generalized epilepsies. Methods: Idiopathic generalized epilepsies were diagnosed according to clinical and EEG criteria following International League Against Epilepsy recommendations. MRI was performed in a 2.0 T scanner using a previously established epilepsy protocol. Images were reviewed, and any abnormality was reported. Patients were divided in those with and without MRI abnormalities. Comparisons were made between these groups concerning age, age at seizure onset, subsyndrome, EEG findings, and seizure control. Results: Of the 134 MRIs evaluated, 33 (24%) showed abnormalities, most of which (88%) were nonspecific. There were eight main abnormalities: arachnoid cyst, diffuse cortical atrophy, basal ganglia abnormalities (signal alterations and prominent perivascular spaces), ventricular abnormalities (uni- or bilateral increased volume of the lateral ventricles), white matter abnormalities (increased T2 signal in the frontal lobes), reduced hippocampal volume, focal gyral abnormality, and area of gliosis in the frontal lobe. Comparisons between the groups showed a higher proportion of EEG focalities in patients with abnormal MRI, which were in most part concordant with the location of the MRI abnormalities. Conclusions: Twenty-four percent of patients with idiopathic generalized epilepsies had MRI abnormalities. However, the majority of these abnormalities were nonspecific.o TEXTO COMPLETO DESTE ARTIGO, ESTARÁ DISPONÍVEL À PARTIR DE AGOSTO DE 2015.67584885
Prevalence and Pattern of Epilepsy Treatment in Different Socioeconomic Classes in Brazil
EEG features in idiopathic generalized epilepsy: Clues to diagnosis
Purpose: To investigate the EEG profile and its contribution for diagnosis and management in a group of patients with a clinical diagnosis of idiopathic generalized epilepsy (IGE) who were referred to a tertiary hospital. Methods: We retrospectively studied clinical and EEG features of 180 consecutive patients with IGE. Eighty patients were diagnosed with juvenile myoclonic epilepsy (JME), 35 had absence epilepsy (AE), 13 had generalized tonic-clonic seizures on awakening (GTCS-A), 28 had generalized tonic-clonic seizures only (TCS), and 24 had adult-onset idiopathic generalized epilepsy (AIGE). The EEGs were classified in typical (synchronous generalized spike or polyspikes-and-wave discharges with normal background), atypical (with clear focalities or asymmetries), and normal. Results: The 493 EEG exams were analyzed. The first EEG was normal in 45% of the 180 patients, and only 33% had typical abnormalities. AE had a higher proportion of typical examinations and needed fewer sequential examinations to register a typical abnormality compared with the other groups. By contrast, the serial EEG profile of TCS and AIGE showed a higher proportion of normal and atypical EEG findings. Conclusions: These findings support previous recommendations that IGE patients should be treated with appropriate therapy based on clinical history. Waiting for a typical abnormal EEG pattern can generate an unacceptable delay in the correct diagnosis and treatment of these patients. In patients with long-term epilepsy, the diagnosis may be difficult. Furthermore, serial EEGs can help to elucidate the syndromic diagnosis, especially in patients with TCS and AIGE.47352352