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Epistaxis during a generalized seizure leading to an atypical ictal SPECT finding at the skull base
Wichert-Ana, Lauro;Ferruzzi, Emerson Henklain;Alexandre Jr, Veriano;Velasco, Tonicarlo Rodrigues;Bianchin, Marino Muxfeldt;Terra-Bustamante, Vera Cristina;Kato, Mery;Santos, Antonio Carlos;Azevedo-Marques, Paulo Mazzoncini de;Oliveira, Lucas Ferrari de;Sakamoto, Américo Ceiki;
Journal of Epilepsy and Clinical Neurophysiology , 2006, DOI: 10.1590/S1676-26492006000700007
Abstract: introduction: generalized tonic-clonic seizures (gtcs) are among the most dramatic types of epileptic seizures and may be accompanied by rising blood pressure and pulse rate, physical injuries from falling, muscular convulsions, tongue biting, or aspiration pneumonia. epistaxis is an uncommon complication of generalized seizures and investigations should exclude local or systemic disorders. objective: we aim to report a 29-year-old male patient with medically intractable right temporal lobe epilepsy whose ictal spect showed a conspicuous high extracerebral accumulation of the tracer at the skull base. methods: the tracer 99mtc-ecd was injected during a gtcs complicated by simultaneous epistaxis during a long term video-electroencephalographic monitoring. results: initially, spect images showed an unexpected hot spot at the skull base suggesting pharyngeal or pituitary tumors. clinical history disclosed chronic sinusitis and rare episodes of epistaxis. white and red cells blood count, platelet count, serum biochemistry, coagulation tests, and rest arterial blood pressure were normal. computed tomography and mri excluded sinusoidal expansive or vascular lesions, head trauma, fractures or acute infections. subtracted spect disclosed a focal high concentration of the radiotracer within the left sphenoid sinus, probably related to the nose bleeding. conclusion: this is a singular case of a brain spect artifact secondary to a nasal bleeding during a generalized seizure that was misinterpreted as neoplastic disease. also, this case raises concerns about the pathophysiological relationship among epileptic seizures, nasal bleedings and chronic sinusitis.
First true initial ictal SPECT in partial epilepsy verified by electroencephalography  [cached]
Jesús Pastor,Luis Domínguez-Gadea,Rafael G Sola,Virgilio Hernando
Neuropsychiatric Disease and Treatment , 2008,
Abstract: Jesús Pastor1, Luis Domínguez-Gadea2, Rafael G Sola3, Virgilio Hernando3, María Luisa Meilán4, Eva De Dios4, José Luis Martínez-Chacón4, Marcos Martínez51Clinical Neurophysiology; 2Nuclear Medicine; 3Neurosurgery; 4Anaesthesiology and Reanimation; Hospital Universitario “La Princesa”, Madrid, Spain; 5Anaesthesiology and Reanimation, Cardiovascular Unit of Adults, Hospital Ramón y Cajal, Madrid, SpainAbstract: Drug-resistant epilepsy can sometimes be treated by surgery. In these cases, an accurate identification of the epileptogenic area must be addressed before resection. Ictal SPECT is one of the presurgical evaluations that can be performed, but usually, the increase in the regional cerebral perfusion observed is produced by diffusion of ictal activity. Here we describe a patient studied with v-EEG and foramen ovale electrodes that suffered a seizure after intravenous infusion of etomidate. The sequence of etomidate administration, followed by radiotracer and seizure was good enough for us to suspect that a true initial ictal SPECT was observed. We have implemented a kinetic model with four compartments, previously described (Andersen 1989), in order to estimate the fraction of hydrophilic radiotracer in the brain during the pre-ictal and ictal periods. This model has shown that the fraction of hydrophilic radiotracer during the seizure into the brain would be between 18.9% and 42.3% of total infused. We show the first true initial ictal SPECT demonstrated by bioelectrical recordings of the brain activity, obtained by a correct succession of events and compatible with theoretical data obtained from the kinetic model.Keywords: etomidate, foramen ovale electrodes, mathematical model, temporal lobe epilepsy
Statistical voxel-wise analysis of ictal SPECT reveals pattern of abnormal perfusion in patients with temporal lobe epilepsy
Amorim, Bárbara Juarez;Etchebehere, Elba Cristina Sá de Camargo;Camargo, Edwaldo Eduardo;Rio, Pablo Augusto;Bonilha, Leonardo;Rorden, Chris;Li, Li Min;Cendes, Fernando;
Arquivos de Neuro-Psiquiatria , 2005, DOI: 10.1590/S0004-282X2005000600014
Abstract: objective: to investigate the pattern of perfusion abnormalities in ictal and interictal brain perfusion spect images (bsi) from patients with temporal lobe epilepsy (tle). method: it was acquired interictal and ictal bsi from 24 patients with refractory tle. bsis were analyzed by visual inspection and statistical parametric mapping (spm2). statistical analysis compared the patients group to a control group of 50 volunteers. the images from patients with left-tle were left-right flipped. results: it was not observed significant perfusional differences in interictal scans with spm. ictal bsi in spm analysis revealed hyperperfusion within ipsilateral temporal lobe (epileptogenic focus) and also contralateral parieto-occipital region, ipsilateral posterior cingulate gyrus, occipital lobes and ipsilateral basal ganglia. ictal bsi also showed areas of hypoperfusion. conclusion: in a group analysis of ictal bsi of patients with tle, voxel-wise analysis detects a network of distant regions of perfusional alteration which may play active role in seizure genesis and propagation.
Avalia??o de foco epileptogênico do lobo temporal: correla??o entre SPECT ictal, ressonancia magnética e ressonancia magnética com espectroscopia de prótons
Diegues, Maria Elena Martins;Pellini, Marcos Pinto;Alves-Leon, Soniza Vieira;Domingues, Romeu C?rtes;
Radiologia Brasileira , 2004, DOI: 10.1590/S0100-39842004000100003
Abstract: the purpose of this study was to determine the degree of concordance between radiological and radioisotopic methods and, if positive, to evaluate the usefulness of ictal spect in the localization of the epileptogenic focus. ictal brain spect, magnetic resonance imaging (mri) and magnetic resonance spectroscopy (mrs) were performed on six patients with refractory temporal lobe epilepsy. ictal spect was performed after withdrawal of the anti-epileptogenic drugs during video-eeg monitoring, using 99mtc-ecd, administered to patients at the time of the ictus. mri was performed in t1, t2 and flair sequences and mrs was obtained using the press technique, with a single voxel positioned in both hippocampi. the statistical analysis included the determination of the values of kappa (k), standard error (se) and significance level (p) for the lateralization of the ictal focus. the analysis of all findings was based on eeg localization of the ictal discharge, seizure duration (109-280 s; 152 s average) and time of radiotracer injection (30-262 s; 96 s average). we obtained correlated data in four patients (67%), and values of k = 0.67, se = 0.38, and p = 0.041. we concluded that there is a concordance between ictal spect, mri and mrs data and the usefulness of the radioisotopic procedure is related to a nondiagnostic eeg and when there is a discordant or misleading diagnosis after a comparative analysis of eeg and mrs.
Ictal and interictal SPECT in patients with frontal lobe epilepsy.- This paper was awarded the ADAC Prize at the Brazilian Congress of Nuclear Medicine, Recife, Brazil, December 1998.  [cached]
Wichert-Ana, Lauro.,Kato, Mery .,Terra Bustamante, Vera Cristina.,Rodrigues Velasco, Tonicarlo.
Alasbimn Journal , 1999,
Abstract: The frontal lobe seizures present variable clinical and electroencephalographic features that play some difficulties in the presurgical work-up for epilepsy. The aim of the present study is to determine the role of ictal and interictal SPECT in the localization of the epileptogenic zone in frontal lobe epilepsies. We evaluated 13 patients, 6 men and 7 women, with mean age of 16yr, and with medically intractable frontal lobe seizures. All patients were submitted to ictal SPECT and 11 also to interictal scans. Ictal SPECT studies were contributive in 54% of patients, and nonlateralized and nonlocalized, or contralateralized in the remaining patients. Interictal SPECT showed normal perfusion in 45,5% of patients, hypoperfusion localized in the suspected epileptogenic zone in 45,5%, and diffuse findings in the other 9%. We conclude that the sensitivity of ictal and interictal SPECT studies in frontal lobe epilepsies is lower than that for temporal lobe seizures, thus confirming previous data.
Discrimination between Ictal and Seizure-Free EEG Signals Using Empirical Mode Decomposition  [PDF]
Ram Bilas Pachori
Journal of Electrical and Computer Engineering , 2008, DOI: 10.1155/2008/293056
Abstract: A new method for analysis of electroencephalogram (EEG) signals using empirical mode decomposition (EMD) and Fourier-Bessel (FB) expansion has been presented in this paper. The EMD decomposes an EEG signal into a finite set of band-limited signals termed intrinsic mode functions (IMFs). The mean frequency (MF) for each IMF has been computed using FB expansion. The MF measure of the IMFs has been used as a feature in order to identify the difference between ictal and seizure-free intracranial EEG signals. It has been shown that the MF feature of the IMFs has provided statistically significant difference between ictal and seizure-free EEG signals. Simulation results are included to illustrate the effectiveness of the proposed method.
Siyad AR
Hygeia : Journal for Drugs and Medicines , 2010,
Abstract: Sinusitis isthe fifth common diagnosis for which an anti biotic is prescribed and about $ 2billion is spent annually on medications to treat nasal and sinus problems.Diagnosis and treating sinusitis is therefore being very important .Acute bacterial sinusitis usuallyoccurs following an upper respiratory infection that result in the obstruction of the osteomeatal complex , impaired mucociliary clearance and production of secretions (L.J.Fajan et al ,1989.) Acute sinusitis is a common illness in primarycare .Studies have demonstrated the difficulty of making the differentialdiagnosis of acute purulent sinusitis based on clinical evaluations alone. This leads to a significant overuse of antibiotics, whichin turn may contribute to increase bacterial resistance. (Morten Lindback. et al.,2002). Sinus diseaseis inherently associated with viralupper respiratory tract infections and occurs in 90% of individuals with common cold. Although thediagnosis of acute bacterial sinusitis is usually based on physical findings, no one sign or symptom iseither sensitive or specific for sinusitis. The predictive power can be significantlyimproved when all signs and symptoms iseither sensitive or specific for sinusitis. (Martin Desrosiers. et al.,2002)There is solid evidence that a positive association between nasal allergyand acute or chronic sinusitis in bothadult and children. (Shin- Wen Huang. et al., 2006 . Acute sinusitis frequentlyfollows upper respiratory tractinfections. Sinusitis or an inflammation of one or more of the para nasalsinuses, affects approximately 16% of USadults, resulting in nearly $ 5.8 billion in annual healthcare costs. (LauriaBarclay et al
Avalia o de foco epileptogênico do lobo temporal: correla o entre SPECT ictal, ressonancia magnética e ressonancia magnética com espectroscopia de prótons  [cached]
Diegues Maria Elena Martins,Pellini Marcos Pinto,Alves-Leon Soniza Vieira,Domingues Romeu C?rtes
Radiologia Brasileira , 2004,
Abstract: O objetivo deste trabalho foi determinar a existência de concordancia entre os métodos radioisotópico e radiológico e, em caso positivo, avaliar a utilidade do SPECT ictal na determina o do foco epileptogênico. Foram realizados SPECT ictal, ressonancia magnética (RM) e ressonancia magnética com espectroscopia de prótons (RME) em seis pacientes com epilepsia de lobo temporal refratária. O SPECT ictal foi realizado após a retirada das drogas antiepilépticas durante monitoramento por vídeo-EEG, utilizando-se o 99mTc-ECD, administrado aos pacientes no início da crise. As imagens de RM foram obtidas em T1, T2 e FLAIR, com cortes de 3 e 5 mm de espessura, e a RME foi realizada com técnica PRESS, com voxel único posicionado no hipocampo, bilateralmente. A análise estatística incluiu os valores de Kappa (k), erro-padr o (ep) e o nível de significancia (p) para a lateraliza o do foco. Os achados foram analisados com base na localiza o por EEG da descarga ictal, no tempo de dura o da crise (109-280 s; média: 152 s) e no tempo de administra o do tra ador (30-262 s; média: 96 s). Obtivemos dados correlatos em quatro pacientes (67%), com valores de k = 0,67, ep = 0,38 e p = 0,041. Concluímos que existe concordancia entre SPECT ictal, RM e RME, e a utilidade do procedimento radioisotópico está relacionada aos casos em que o EEG n o é diagnóstico e quando há discordancia ou indefini o diagnóstica na análise comparativa entre EEG, RM e RME.
SPECT Imaging of Epilepsy: An Overview and Comparison with F-18 FDG PET  [PDF]
Sunhee Kim,James M. Mountz
International Journal of Molecular Imaging , 2011, DOI: 10.1155/2011/813028
Abstract: Epilepsy surgery is highly effective in treating refractory epilepsy, but requires accurate presurgical localization of the epileptogenic focus. Briefly, localization of the region of seizure onset traditionally dependents on seizure semiology, scalp EEG recordings and correlation with anatomical imaging modalities such as MRI. The introduction of noninvasive functional neuroimaging methods, including single-photon emission computed tomography (SPECT) and positron emission tomography (PET) has dramatically changed the method for presurgical epilepsy evaluation. These imaging modalities have become powerful tools for the investigation of brain function and are an essential part of the evaluation of epileptic patients. Of these methods, SPECT has the practical capacity to image blood flow functional changes that occur during seizures in the routine clinical setting. In this review we present the basic principles of epilepsy SPECT and PET imaging. We discuss the properties of the SPECT tracers to be used for this purpose and imaging acquisition protocols as well as the diagnostic performance of SPECT in addition to SPECT image analysis methods. This is followed by a discussion and comparison to F-18 FDG PET acquisition and imaging analysis methods. 1. Introduction Epilepsy surgery can be highly effective in treating refractory epilepsy if performed in properly selected patients with well-delineated ictal foci [1]. The greatest challenge is accurate localization, but only a small fraction of the patients whose epilepsy becomes refractory ultimately receive surgery. In the past, localization of the region of seizure onset was dependent upon scalp, cortical, and depth electroencephalography (EEG). However, scalp EEG has disadvantages such as dependency on cortical surface effects and low spatial resolution that can lead to mislocalization of epileptogenic foci. Both cortical and depth EEG have a limited spatial sampling area that is confined to regions accessible by electrode placement. Depth EEG can detect signals from deeper structures, but it is more invasive, which can lead to surgical complications [2]. The introduction of noninvasive neuroimaging methods, such as single-photon emission computed tomography (SPECT), positron emission tomography (PET), and magnetic resonance imaging (MRI), has dramatically changed presurgical epilepsy evaluation. These imaging methods have become powerful tools for the investigation of brain function and an essential part of the evaluation of epileptic patients. Of these methods, only SPECT has the practical capacity to
Seizure (Ictal)—EEG Characteristics in Subgroups of Depressive Disorder in Patients Receiving Electroconvulsive Therapy (ECT)—A Preliminary Study and Multivariate Approach  [PDF]
Bj rn Wahlund,Paolo Piazza,Dietrich von Rosen,Benny Liberg,Hans Liljenstr m
Computational Intelligence and Neuroscience , 2009, DOI: 10.1155/2009/965209
Abstract: Objectives. Examine frequency distributions of ictal EEG after ECT stimulation in diagnostic subgroups of depression. Methods. EEG registration was consecutively monitored in 33 patients after ECT stimulation. Patients were diagnosed according to DSM IV and subdivided into: (1) major depressive disorder with psychotic features (=7), (2) unipolar depression (=20), and (3) bipolar depression (=6). Results. Results indicate that the diagnostically subgroups differ in their ictal EEG frequency spectrumml: (1) psychotic depression has a high occurrence of delta and theta waves, (2) unipolar depression has high occurrence of delta, theta and gamma waves, and (3) bipolar depression has a high occurrence of gamma waves. A linear discriminant function separated the three clinical groups with an accuracy of 94%. Conclusion. Psychotic depressed patients differ from bipolar depression in their frequency based on probability distribution of ictal EEG. Psychotic depressed patients show more prominent slowing of EEG than nonpsychotic depressed patients. Thus the EEG results may be supportive in classifying subgroups of depression already at the start of the ECT treatment.
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