Seizure Control (seizure + control)

Distribution by Scientific Domains
Distribution within Medical Sciences


Selected Abstracts


Electrical Stimulation of the Hippocampal Epileptic Foci for Seizure Control: A Double-Blind, Long-Term Follow-Up Study

EPILEPSIA, Issue 10 2007
Ana Luisa Velasco
Summary:,Purpose: Our aim was to evaluate the safety and efficacy of electrical stimulation of the hippocampus in a long-term follow-up study, as well as its impact on memory performance in the treatment of patients with refractory mesial temporal lobe epilepsy. Methods: Nine patients were included. All had refractory partial complex seizures, some with secondary generalizations. All patients had a 3-month-baseline-seizure count, after which they underwent bilateral hippocampal diagnostic electrode implantation to establish focus laterality and location. Three patients had bilateral, and six, unilateral foci. Diagnostic electrodes were explanted and definitive Medtronic electrodes were implanted directed into the hippocampal foci. Position was confirmed with MRI and afterwards, the deep brain stimulation system internalized. Patients signed the informed consent approved by the Hospital's Ethics Committee and began a double-blind stimulation protocol. Patients attended a medical appointment every 3 months for seizure diary collection, deep brain stimulation system checkup, and neuropsychological testing. Results: Follow-up ranged from 18 months to 7 years. Patients were divided in two groups: five had normal MRIs and seizure reduction of >95%, while four had hippocampal sclerosis and seizure reduction of 50,70%. No patient had neuropsychological deterioration, nor did any patient show side effects. Three patients were explanted after 2 years due to skin erosion in the trajectory of the system. Conclusions: Electrical stimulation of the hippocampus provides a nonlesional method that improves seizure outcome without memory deterioration in patients with hippocampal epileptic foci. [source]


Brain Blood-flow Alterations Induced by Therapeutic Vagus Nerve Stimulation in Partial Epilepsy: II.

EPILEPSIA, Issue 9 2004
Low Levels of Stimulation, Prolonged Effects at High
Summary:,Purpose: To measure vagus nerve stimulation (VNS)-induced cerebral blood flow (CBF) effects after prolonged VNS and to compare these effects with immediate VNS effects on CBF. Methods: Ten consenting partial epilepsy patients had positron emission tomography (PET) with intravenous [15O]H2O. Each had three control scans without VNS and three scans during 30 s of VNS, within 20 h after VNS began (immediate-effect study), and repeated after 3 months of VNS (prolonged study). After intrasubject subtraction of control from stimulation scans, images were anatomically transformed for intersubject averaging and superimposed on magnetic resonance imaging (MRI) for anatomic localization. Changes on t-statistical maps were considered significant at p < 0.05 (corrected for multiple comparisons). Results: During prolonged studies, CBF changes were not observed in any regions that did not have CBF changes during immediate-effect studies. During both types of studies, VNS-induced CBF increases were similarly located in the bilateral thalami, hypothalami, inferior cerebellar hemispheres, and right postcentral gyrus. During immediate-effect studies, VNS decreased bilateral hippocampal, amygdalar, and cingulate CBF and increased bilateral insular CBF; no significant CBF changes were observed in these regions during prolonged studies. Mean seizure frequency decreased by 25% over a 3-month period between immediate and prolonged PET studies, compared with 3 months before VNS began. Conclusions: Seizure control improved during a period over which some immediate VNS-induced CBF changes declined (mainly over cortical regions), whereas other VNS-induced CBF changes persisted (mainly over subcortical regions). Altered synaptic activities at sites of persisting VNS-induced CBF changes may reflect antiseizure actions. [source]


Does Neuroticism Influence Cognitive Self-Assessment After Epilepsy Surgery?

EPILEPSIA, Issue 10 2000
S. Cañizares
Summary Purpose: To examine how cognitive, personality, and seizure outcome variables influence the subjective cognitive functioning of patients with refractory temporal lobe seizures after epilepsy surgery. Methods: Thirty-three consecutive patients with drug-resistant partial epilepsy who underwent surgical treatment at a tertiary referral university epilepsy center were tested before surgery and 1 year after surgery. Objective cognitive and subjective cognitive functioning tests were used, and personality was assessed. Seizure control was operationalized as a dichoto-mous variable. Results: A significant inverse relationship was found between neuroticism and subjective cognitive functioning. None of the other pre- and postoperative cognitive and surgery outcome variables were significant predictors of subjective cognitive functioning, even after controlling for the effect of neuroticism. Conclusions: Subjective and objective memory functioning are independent in patients with epilepsy after surgical treatment. Subjective memory functioning appears to be related not to seizure relief but to neuroticism. These data suggest that psychological factors such as personality traits predisposing to emotional distress should be taken into consideration in the clinical management and counseling of patients undergoing epilepsy surgery. [source]


Subacute sclerosing panencephalitis: an update

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 10 2010
JOSE GUTIERREZ
Subacute sclerosing panencephalitis (SSPE) is a chronic encephalitis occurring after infection with measles virus. The prevalence of the disease varies depending on uptake of measles vaccination, with the virus disproportionally affecting regions with low vaccination rates. The physiopathology of the disease is not fully understood; however, there is evidence that it involves factors that favour humoral over cellular immune response against the virus. As a result, the virus is able to infect the neurons and to survive in a latent form for years. The clinical manifestations occur, on average, 6 years after measles virus infection. The onset of SSPE is insidious, and psychiatric manifestations are prominent. Subsequently, myoclonic seizures usually lead to a final stage of akinetic mutism. The diagnosis is clinical, supported by periodic complexes on electroencephalography, brain imaging suggestive of demyelination, and immunological evidence of measles infection. Management of the disease includes seizure control and avoidance of secondary complications associated with the progressive disability. Trials of treatment with interferon, ribavirin, and isoprinosine using different methodologies have reported beneficial results. However, the disease shows relentless progression; only 5% of individuals with SSPE undergo spontaneous remission, with the remaining 95% dying within 5 years of diagnosis. [source]


Long-term outcomes of children treated with the ketogenic diet in the past

EPILEPSIA, Issue 7 2010
Amisha Patel
Summary Purpose:, The ketogenic diet has well-established short- and long-term outcomes for children with intractable epilepsy, but only for those actively receiving it. However, no information exists about its long-term effects years after it has been discontinued. Methods:, Living subjects were identified who were treated at the Johns Hopkins Hospital with the ketogenic diet from November 1993 to December 2008 for ,1 month, and had discontinued it ,6 months prior to this study. Of 530 patients who were eligible, 254 were successfully contacted by phone or e-mail with a survey and request for laboratory studies. Results:, Questionnaires were completed by 101 patients, with a median current age of 13 years (range 2,26 years). Median time since discontinuing the ketogenic diet was 6 years (range 0.8,14 years). Few (8%) still preferred to eat high fat foods. In comparison to the 52% responder rate (>50% seizure reduction) at ketogenic diet discontinuation, 79% were now similarly improved (p = 0.0001). Ninety-six percent would recommend the ketogenic diet to others, yet only 54% would have started it before trying anticonvulsants. Lipids were normal (mean total cholesterol 158 mg/dl), despite most being abnormal while on the ketogenic diet. The mean Z scores for those younger than age 18 years were ,1.28 for height and ,0.79 for weight. In those 18 years of age or older, the mean body mass index (BMI) was 22.2. Discussion:, This is the first study to report on the long-term effects of the ketogenic diet after discontinuation. The majority of subjects are currently doing well with regard to health and seizure control. [source]


Changes in individual and group spatial and verbal learning characteristics after anterior temporal lobectomy

EPILEPSIA, Issue 6 2009
Mario F. Dulay
Summary Purpose:, To evaluate the effects of anterior temporal lobectomy (ATL) on individual and group spatial and verbal learning and memory abilities as a function of side of surgery and seizure control outcome. Methods:, We evaluated pre- and postsurgical learning and memory abilities of 75 left-hemisphere language dominant individuals who underwent ATL (33 left, 42 right) using the 8-trial Nonverbal Selective Reminding test and the 12-trial Verbal Selective Reminding test. Results:, Reliable change index methods indicated that 40.5% of individuals who underwent right-ATL had a clinically significant decline in spatial memory, and 62.5% of individuals who underwent left-ATL had a significant reduction in verbal memory. Growth curve analyses indicated that both side of surgery and poor seizure outcome independently affected the learning slope in the best fitting models. Left-ATL reduced the slope, but did not affect the overall shape, of verbal learning across trials. On the other hand, poor seizure control outcome affected the slope of spatial learning regardless of the side of surgery. Discussion:, Results demonstrate both individual and group declines in spatial memory and learning after ATL. Results suggest that individuals who undergo right-ATL should be counseled regarding the likelihood of a decline in spatial memory and learning abilities after ATL. Results also suggest that individuals with poor seizure control after ATL should be referred for rehabilitation services given the significant declines in spatial and verbal memory that occurred in our sample regardless of side of surgery. [source]


The clinical impact of pharmacogenetics on the treatment of epilepsy

EPILEPSIA, Issue 1 2009
Wolfgang Löscher
Summary Drug treatment of epilepsy is characterized by unpredictability of efficacy, adverse drug reactions, and optimal doses in individual patients, which, at least in part, is a consequence of genetic variation. Since genetic variability in drug metabolism was reported to affect the treatment with phenytoin more than 25 years ago, the ultimate goal of pharmacogenetics is to use the genetic makeup of an individual to predict drug response and efficacy, as well as potential adverse drug events. However, determining the practical relevance of pharmacogenetic variants remains difficult, in part because of problems with study design and replication. This article reviews the published work with particular emphasis on pharmacogenetic alterations that may affect efficacy, tolerability, and safety of antiepileptic drugs (AEDs), including variation in genes encoding drug target (SCN1A), drug transport (ABCB1), drug metabolizing (CYP2C9, CYP2C19), and human leucocyte antigen (HLA) proteins. Although the current studies associating particular genes and their variants with seizure control or adverse events have inherent weaknesses and have not provided unifying conclusions, several results, for example that Asian patients with a particular HLA allele, HLA-B*1502, are at a higher risk for Stevens-Johnson syndrome when using carbamazepine, are helpful to increase our knowledge how genetic variation affects the treatment of epilepsy. Although genetic testing raises ethical and social issues, a better understanding of the genetic influences on epilepsy outcome is key to developing the much needed new therapeutic strategies for individuals with epilepsy. [source]


Medium-chain triglyceride (MCT) ketogenic therapy

EPILEPSIA, Issue 2008
Yeou-mei Christiana Liu
Summary The medium-chain triglyceride diet (MCTD) is a variant of the classic 4:1 ketogenic diet (KD) introduced in 1971 by Huttenlocher as an attempt to improve the palatability of the KD by allowing more carbohydrates yet preserving ketosis. Although initially found to be equally effective as the classic KD, use of the MCTD declined because of frequent gastrointestinal side effects such as cramps, diarrhea, and vomiting. Recently, we have used the MCTD in more than 50 patients. We have found excellent seizure control, similar to the classic KD, and with careful monitoring, we have encountered minimal side effects. The MCTD should remain a viable dietary option for children with refractory epilepsy who have large appetites, can tolerate more calories, or cannot accept the restrictions of the classic KD. [source]


Generic Products of Antiepileptic Drugs (AEDs): Is It an Issue?

EPILEPSIA, Issue 10 2007
Meir Bialer
Summary:, The availability of generic products of antiepileptic drugs (AEDs) has raised the following concerns: (1) Do generic AEDs work as well as brand AEDs in terms of their efficacy, safety and quality? (2) Can generic AEDs be used as substitutions for brand AEDs? and (3) Can generic products of AEDs be used interchangeably? The traditional average bioequivalence analysis addresses concern 1 but does not provide a complete adequate response to concerns 2 and 3. Drug interchangeability can be classified as drug prescribability or drug switchability. Drug prescribability refers to the situation where a patient is treated for the first time so that either a brand or a bioequivalent generic AED can be chosen. Drug switchability refers to the situation in which a brand AED is switched to a bioequivalent generic product of the same AED. The traditional average bioequivalence approach is sufficient to evaluate the prescribability of generic products, but does not ensure the switchability between prescribable formulations. The necessity of assuring switchability of two formulations can be addressed by individual bioequivalence. While the switch to generic AEDs is well tolerated by many patients and in general cost-effective, seizure control should not be sacrificed on the basis of cost alone, as the major end point in treating epilepsy with AEDs is seizure control without side effects. Until we have individual (within patient) bioequivalence data on generic AEDs and/or the tools to a priori identify the subset of patients susceptible to the generic switch, a switch of AED products in seizure-free patients is not recommended. [source]


Behavioral and Psychiatric Comorbidities in Pediatric Epilepsy: Toward an Integrative Model

EPILEPSIA, Issue 9 2007
Joan K. Austin
Summary:, It is well recognized that children with epilepsy are at heightened risk for developing behavior problems and psychiatric disorders. Studies identifying factors associated with child behavior were reviewed and findings were placed into two broad categories for review and critique: illness-related variables and psychosocial variables. Illness-related variables were seizure frequency and seizure control, type of epilepsy, age of onset, duration of illness, and antiepileptic drugs. Psychosocial variables were reviewed using a family stress framework: stressors, perceptions, adaptive resources, coping, and family adjustment. After the literature on each category is reviewed, an integrated heuristic model that includes key illness-related and psychosocial variables is presented. [source]


Molecular Neuropathology of Temporal Lobe Epilepsy: Complementary Approaches in Animal Models and Human Disease Tissue

EPILEPSIA, Issue 2007
Michael Majores
Summary:, Patients with temporal lobe epilepsies (TLE) frequently develop pharmacoresistance to antiepileptic treatment. In individuals with drug-refractory TLE, neurosurgical removal of the epileptogenic focus provides a therapy option with high potential for seizure control. Biopsy specimens from TLE patients constitute unique tissue resources to gain insights in neuropathological and molecular alterations involved in human TLE. Compared to human tissue specimens in most neurological diseases, where only autopsy material is available, the bioptic tissue samples from pharmacoresistant TLE patients open rather exceptional preconditions for molecular biological, electrophysiological as well as biochemical experimental approaches in human brain tissue, which cannot be carried out in postmortem material. Pathological changes in human TLE tissue are multiple and relate to structural and cellular reorganization of the hippocampal formation, selective neurodegeneration, and acquired changes of expression and distribution of neurotransmitter receptors and ion channels, underlying modified neuronal excitability. Nevertheless, human TLE tissue specimens have some limitations. For obvious reasons, human TLE tissue samples are only available from advanced, drug-resistant stages of the disease. However, in many patients, a transient episode of status epilepticus (SE) or febrile seizures in childhood can induce multiple structural and functional alterations that after a latency period result in a chronic epileptic condition. This latency period, also referred to as epileptogenesis, cannot be studied in human TLE specimens. TLE animal models may be particularly helpful in order to shed characterize new molecular pathomechanisms related to epileptogenesis and open novel therapeutic strategies for TLE. Here, we will discuss experimental approaches to unravel molecular,neuropathological aspects of TLE and highlight characteristics and potential of molecular studies in human and/or experimental TLE. [source]


Hemispheric Surgery in Children with Refractory Epilepsy: Seizure Outcome, Complications, and Adaptive Function

EPILEPSIA, Issue 1 2007
Sheikh Nigel Basheer
Summary:,Purpose: To describe seizure control, complications, adaptive function and language skills following hemispheric surgery for epilepsy. Methods: Retrospective chart review of patients who underwent hemispheric surgery from July 1993 to June 2004 with a minimum follow-up of 12 months. Results: The study population comprised 24 children, median age at seizure onset six months and median age at surgery 41 months. Etiology included malformations of cortical development (7), infarction (7), Sturge-Weber Syndrome (6), and Rasmussen's encephalitis (4). The most frequent complication was intraoperative bleeding (17 transfused). Age <2 yr, weight <11 kg, and hemidecortication were risk factors for transfusion. Postoperative complications included aseptic meningitis (6), and hydrocephalus (3). At median follow-up of 7 yr, 79% of patients are seizure free. Children with malformations of cortical development and Rasmussen's encephalitis were more likely to have ongoing seizures. Overall adaptive function scores were low, but relative strengths in verbal abilities were observed. Shorter duration of epilepsy prior to surgery was related significantly to better adaptive functioning. Conclusions: Hemispheric surgery is an effective therapy for refractory epilepsy in children. The most common complication was bleeding. Duration of epilepsy prior to surgery is an important factor in determining adaptive outcome. [source]


Drug Resistance in Epilepsy: Putative Neurobiologic and Clinical Mechanisms

EPILEPSIA, Issue 6 2005
Dieter Schmidt
Summary:, Drug-resistant epilepsy with uncontrolled severe seizures despite state-of-the-art medical treatment continues to be a major clinical problem for up to one in three patients with epilepsy. Although drug resistance may emerge or remit in the course of epilepsy or its treatment, in most patients, drug resistance seems to be continuous and to occur de novo. Unfortunately, current antiepileptic drugs (AEDs) do not seem to prevent or to reverse drug resistance in most patients, but add-on therapy with novel AEDs is able to exert a modest seizure reduction in as many as 50% of patients in short-term clinical trials, and a few become seizure free during the trial. It is not known why and how epilepsy becomes drug resistant, while other patients with seemingly identical seizure types can achieve seizure control with medication. Several putative mechanisms underlying drug resistance in epilepsy have been identified in recent years. Based on experimental and clinical studies, two major neurobiologic theories have been put forward: (a) removal of AEDs from the epileptogenic tissue through excessive expression of multidrug transporters, and (b) reduced drug-target sensitivity in epileptogenic brain tissue. On the clinical side, genetic and clinical features and structural brain lesions have been associated with drug resistance in epilepsy. In this article, we review the laboratory and clinical evidence to date supporting the drug-transport and the drug-target hypotheses and provide directions for future research, to define more clearly the role of these hypotheses in the clinical spectrum of drug-resistant epilepsy. [source]


Quality of Life of People with Epilepsy in Iran, the Gulf, and Near East

EPILEPSIA, Issue 1 2005
Gus A. Baker
Summary:,Purpose: To study the impact of epilepsy and its treatment on the quality of life of people living in Iran and in countries in the Gulf and Near East. Methods: Clinical, demographic, and psychosocial details were collected through the use of a self-completed questionnaire distributed to patients attending hospital outpatient clinics. Results: Data were collected from 3,889 people with epilepsy from 10 countries. More than 40% of all respondents had frequent seizures, and reported levels of side effects from medication were high, the most commonly reported being nervousness, headaches, and tiredness. A significant number of respondents reported changing their medications because of side effects or poor seizure control. Respondents reported that epilepsy and its treatment had a significant impact on a number of different aspects of their daily lives. A significant number of respondents felt stigmatized by their epilepsy. Reported health status was reduced when compared with that of people without epilepsy, particularly for physical and social functioning and energy and vitality, as assessed by using a generic health status measure, the SF-36. Conclusions: This is the largest study to date documenting the impact of epilepsy and its treatment in Iran, the Gulf, and Near East regions. Differences were found between the quality-of-life profiles of respondents in this study and those who participated in an earlier parallel study in Europe. [source]


Navigating toward Fetal and Maternal Health: The Challenge of Treating Epilepsy in Pregnancy

EPILEPSIA, Issue 10 2004
Torbjörn Tomson
Summary:, A rational approach to the treatment of women of childbearing potential with epilepsy has been hampered by the lack of conclusive data on the comparative teratogenic potential of different antiepileptic drugs (AEDs). Although, several cohort studies on birth defects associated with AED use during pregnancy have been published, these have generally failed to demonstrate differences in malformation rates between AEDs, probably mainly due to insufficient power. In particular, pregnancies with new generation AEDs have been too few. In recent years, pregnancy registries have been introduced to overcome this problem,EURAP (an international collaboration), the North American, and the U.K. AED and pregnancy registries are observational studies that prospectively assess pregnancy outcome after AED exposure using slightly different methods. Each has enlisted 3,5,000 pregnancies in women with epilepsy, and the North American and the U.K. have released preliminary observations. Thus the U.K. registry reported a higher malformation rate with valproate, 5.9% (4.3,8.2%; 95% CI), than with carbamazepine, 2.3% (1.4,3.7%), and lamotrigine, 2.1% (1.0,4.0%). Most of the more recent cohort studies have also identified a nonsignificant trend toward a higher teratogenicity with valproate. These signals need to be interpreted with some caution since none of the studies to date have fully assessed the impact of possible confounders, such as type of epilepsy, family history of birth defects, etc. However, with increasing number of pregnancies it should be possible in the near future for the pregnancy registries to take such confounding factors into account and thus make more reliable assessments of the causal relationship between exposure to specific AEDs and teratogenic risks. While awaiting more conclusive results, it appears reasonable to be cautious in prescribing valproate to women considering to become pregnant if other suitable treatment alternatives, and with less teratogenic potential, are available. Any attempt to change treatment should, however, be accomplished well before conception. The importance of maintained seizure control must also be kept in mind, and the woman who needs valproate to control her seizures should not be discouraged from pregnancy, provided that counseling at the best of available knowledge is given. [source]


High-resolution MRI Enhances Identification of Lesions Amenable to Surgical Therapy in Children with Intractable Epilepsy

EPILEPSIA, Issue 8 2004
Monisha Goyal
Summary:,Purpose: Many children with refractory epilepsy can achieve better seizure control with surgical therapy. An abnormality on magnetic resonance imaging (MRI), along with corroborating localization by other modalities, markedly increases chances of successful surgical outcome. We studied the impact of high-resolution MRI on the surgical outcome of intractable epilepsy. Methods: High-resolution MRI using four-coil phased surface array was obtained as part of the comprehensive presurgical protocol for children with focal onset intractable seizures evaluated by our epilepsy center during the first half of 2002. Results: Thirteen consecutive children, ages 5 to 18 years, entered this prospective study. For four patients with a lesion on a recent MRI examination with a standard head coil, management did not change with high-resolution MRI. Standard MRI in the other nine patients did not identify a lesion. However, high-resolution MRI with the phased-array surface coil found previously undiagnosed focal abnormalities in five of nine patients. These abnormalities included hippocampal dysplasia, hippocampal atrophy, and dual pathology with frontal cortical dysplasia. In four of nine patients, no identifiable lesion was identified on the high-resolution MRI. All patients underwent invasive monitoring. In three of five patients, newly diagnosed lesions correlated with EEG abnormalities, and resection was performed. Conclusions: In our center, high-resolution MRI identified lesions not detected by standard MRI in more than half the children (56%). Technical advances such as four-coil phased surface array MRI can help identify and better delineate lesions, improving the diagnosis of patients who are candidates for surgical treatment of refractory epilepsy. [source]


The Multicenter Study of Epilepsy Surgery: Recruitment and Selection for Surgery

EPILEPSIA, Issue 11 2003
Anne T. Berg
Summary:,Purpose: Multiple studies have examined predictors of seizure outcomes after epilepsy surgery. Most are single-center series with limited sample size. Little information is available about the selection process for surgery and, in particular, the proportion of patients who ultimately have surgery and the characteristics that identify those who do versus those who do not. Such information is necessary for providing the epidemiologic and clinical context in which epilepsy surgery is currently performed in the United States and in other developed countries. Methods: An observational cohort of 565 surgical candidates was prospectively recruited from June 1996 through January 2001 at six Northeastern and one Midwestern surgical centers. Standardized eligibility criteria and protocol for presurgical evaluations were used at all seven sites. Results: Three hundred ninety-six (70%) study subjects had resective surgery. Clinical factors such as a well-localized magnetic resonance imaging (MRI) abnormality and consistently localized EEG findings were most strongly associated with having surgery. Of those who underwent intracranial monitoring (189, 34%), 85% went on to have surgery. Race/ethnicity and marital status were marginally associated with having surgery. Age, education, and employment status were not. Demographic factors had little influence over the surgical decision. More than half of the patients had intractable epilepsy for ,10 years and five or more drugs had failed by the time they initiated their surgical evaluation. During the recruitment period, eight new antiepileptic drugs were approved by the Food and Drug Administration for use in the United States and came into increasing use in this study's surgical candidates. Despite the increased availability of new therapeutic options, the proportion that had surgery each year did not fluctuate significantly from year to year. This suggests that, in this group of patients, the new drugs did not provide a substantial therapeutic benefit. Conclusions: Up to 30% of patients who undergo presurgical evaluations for resective epilepsy surgery ultimately do not have this form of surgery. This is a group whose needs are not currently met by available therapies and procedures. Lack of clear localizing evidence appears to be the main reason for not having surgery. To the extent that these data can address the question, they suggest that repeated attempts to control intractable epilepsy with new drugs will not result in sustained seizure control, and eligible patients will proceed to surgery eventually. This is consistent with recent arguments to consider surgery earlier rather than later in the course of epilepsy. Postsurgical follow-up of this group will permit a detailed analysis of presurgical factors that predict the best and worst seizure outcomes. [source]


Absence Epilepsy with Onset before Age Three Years: A Heterogeneous and Often Severe Condition

EPILEPSIA, Issue 7 2003
Yves Chaix
Summary: Purpose: The classification of epilepsies and epileptic syndromes recognizes three syndromes with typical absences [TA, i.e., childhood and juvenile absence epilepsies (CAE and JAE), and epilepsy with myoclonic absences (EMA), none of which is characterized by onset in early childhood]. Although several other forms of absence epilepsies have been described recently, none concerns infants and very young children, and little is known about the nosology and prognosis of early-onset absences. Methods: We retrospectively selected all cases with onset of absences as the only or major seizure type before age 3 years and ,2 years of follow-up among cases newly referred between 1986 and 2002. Neurospychological assessments (generally IQ measure), behavior patterns, and schooling situations were reviewed for each child. Results: We found 10 patients (7 F, 3 M). No child had sensory or motor deficits: neuroimaging was performed in nine and was normal in eight, with aspecfic findings in one. Only two could be characterized as CAE and EMA, respectively, both with seizure control and a good cognitive outcome. Among the remaining eight cases, four had a fairly homogeneous presentation with predominantly brief absences and clearly asymmetric interictal EEGs. All eight had neuropsychological and/or behavioral difficulties. Three had full seizure control, and five, persisting absences, with a follow-up ranging beetween 2 years 8 months to 9 years 4 months; only one child was older than 12 years. Conclusions: Great heterogeneity exists among absence epilepsies of early onset, which are rare conditions. Only a few patients can be categorized into well-known syndromes. The overall prognosis is poor. Early onset of absences is uncommon, and multicenter studies should help clarify the nosology and prognosis. [source]


A Kindling Model of Pharmacoresistant Temporal Lobe Epilepsy in Sprague,Dawley Rats Induced by Coriaria Lactone and Its Possible Mechanism

EPILEPSIA, Issue 4 2003
Ying Wang
Summary: ,Purpose: The aim of this study was to develop a new animal model of pharmacoresistant temporal lobe epilepsy (TLE) by repeated intramuscular injection of Coriaria lactone (CL) at subthreshold dosages and to explore the mechanisms that might be involved. Methods: Healthy male Sprague,Dawley rats (n = 160) were randomized into four groups during the kindling process: three groups (n = 50 for each group) received CL injection at subthreshold dosages (1.25, 1.5, and 1.75 mg/kg, respectively), and ten received normal saline (NS) injection as a control group. The maximal human adult dosage of carbamazepine (CBZ), valproate (VPA), and phenytoin (PHT) was administered as monotherapy to different groups of kindled rats for 1 month (n = 20 for each group). Changes in EEG recording, seizure number, intensity (expressed as grade 1,5 according to Racine stage), and duration, including spontaneous seizures during different interventions, were compared. The expression of P-170, a multiple drug resistance gene (MDR1) encoding P-glycoprotein, was measured in brain samples from different groups of experimental rats by using an image analysis and measurement system (ImagePro-Plus 4.0). Results: A total of 70 (46.7%) rats were fully kindled with a median of 15 (seven to 20) CL injections. Electrocorticogram (ECoG) including hippocampal (EHG) monitoring revealed the temporal lobe origins of epileptiform potentials, which were consistent with the behavioral changes observed. Spontaneous seizures occurred with frequency and diurnal patterns similar to those of human TLE. The antiepileptic drugs (AEDs) tested lacked a satisfactory seizure control. The maximal P-170 expression was in the kindled rats with AED treatment; the next highest was in the kindled rats without AED intervention. Nonkindled SD rats with CL injection also had increased P-170 expression compared with control SD rats. Conclusions: The study provided a simple and stable animal TLE kindling model with pharmacoresistant properties. The pharmacoresistance observed in the kindled rats to CBZ, VPA, and PHT at maximal human adult dosages together with the increased P-170 expression was a distinct feature of this model. This model might be used in further investigations of the mechanisms involved in pharmacoresistant TLE and for developing new AEDs. [source]


A Proton Magnetic Resonance Spectroscopy Study of Metabolites in the Occipital Lobes in Epilepsy

EPILEPSIA, Issue 4 2003
Robert J. Simister
Summary: ,Purpose: ,-Amino butyric acid (GABA) and glutamate, respectively the principal inhibitory and excitatory neurochemicals in the brain, are visible to proton magnetic resonance spectroscopy (MRS). We report a study of GABA+ (GABA plus homocarnosine) and GLX (glutamate plus glutamine) concentrations in the occipital lobes in patients with idiopathic generalised epilepsy (IGE) and in patients with occipital lobe epilepsy (OLE). Methods: Fifteen patients with IGE, 15 patients with OLE, and 15 healthy volunteers were studied. A single voxel was prescribed in the occipital lobes for each subject. PRESS localised short-echo-time MRS was performed to measure GLX by using LCModel. A double quantum GABA filter was used to measure GABA+. Segmented T1 -weighted images gave the tissue composition of the prescribed voxel. Results: Grey-matter proportion, GLX, and GABA+ were all elevated in IGE. However, analysis using grey-matter proportion as a covariable showed no significant group differences. No correlation was observed between GABA+ concentration and either seizure frequency or time since last seizure. Conclusions: GLX and GABA+ were elevated in IGE. Elevated grey-matter content in the IGE group despite normal MRI appearance can be expected to account for some or all of this observed elevation of GLX and GABA+. GABA+ concentration did not correlate with seizure control or duration since most recent seizure. [source]


Lateralising Value of Neuropsychological Protocols for Presurgical Assessment of Temporal Lobe Epilepsy

EPILEPSIA, Issue 3 2003
Nozomi Akanuma
Summary: ,Purpose: To estimate the value of neuropsychological measurements in determining the side of seizure onset for presurgical assessment in patients with temporal lobe epilepsy. The lateralising value of neuropsychological protocols was evaluated for all patients and in subpopulations depending on surgical outcome with regard to seizure control, speech dominance, neuropathology, and need for intracranial EEG recordings. Methods: A battery of neuropsychological procedures was carried out preoperatively in 125 patients who underwent left (n = 66) or right (n = 59) temporal lobectomies. Binary logistic regression analysis was performed to find sets of variables that allowed the best prediction of the side of seizure onset (assumed to be the operated-on side). Results: Combinations of noninvasive neuropsychological tests and Wada subscores showed the highest lateralising values: 80.8% for all patients, 79.4% in seizure-free patients, 86.0% in patients not rendered seizure free, 85.7% in left speech patients, 77.8% in non,left speech patients, 89.3% in patients with mesial temporal sclerosis (MTS), 78.1% in non-MTS patients, 80.3% in patients who underwent intracranial EEG recordings, and 77.3% in those who did not. Conclusions: The lateralising value (80-90%) of neuropsychological protocols appears similar to that of other tests widely accepted for lateralisation (ictal and interictal scalp EEG and neuroimaging). Attention should be paid to neuropsychological results, particularly from the Wada test, during presurgical assessment of temporal lobe epilepsy, as they can provide strong support for findings from other lateralising tests, particularly in patients with presumed MTS or in left-speech patients. [source]


Seizure Suppression by Adenosine-releasing Cells Is Independent of Seizure Frequency

EPILEPSIA, Issue 8 2002
Detlev Boison
Summary: ,Purpose: Intraventricular cellular delivery of adenosine was recently shown to be transiently efficient in the suppression of seizure activity in the rat kindling model of epilepsy. We tested whether the suppression of seizures by adenosine-releasing grafts was independent of seizure frequency. Methods: Adenosine-releasing cells were encapsulated and grafted into the lateral brain ventricle of rats kindled in the hippocampus. During 4 weeks after grafting, electric test stimulations were delivered at a frequency of either once a week or 3 times per week. Seizure activity was evaluated by visual scoring of seizure severity and by the recording of EEGs. Results: Adenosine released from encapsulated cells exerted potent antiepileptic activity for ,2 weeks. One week after grafting, treated rats displayed a complete protection from clonic seizures, and a protection from focal seizures was observed in the majority of animals. Seizure suppression was accompanied by a reduction of afterdischarges in EEG recordings. The protective efficacy of the grafted cells was the same irrespective of whether electrical test stimulations were delivered 1 or 3 times per week. Rats receiving control grafts continued to display full clonic convulsions. Conclusions: This study demonstrated that the frequency of test stimulations did not influence the seizure-suppressive potential of adenosine-releasing grafts. Thus the local delivery of adenosine is likely to be effective in seizure control over a threefold range of seizure-discharge frequency. [source]


Topiramate in Patients with Learning Disability and Refractory Epilepsy

EPILEPSIA, Issue 4 2002
Kevin Kelly
Summary: ,Purpose: Management of seizures in learning disabled people is challenging. This prospective study explored the efficacy and tolerability of adjunctive topiramate (TPM) in patients with learning disability and refractory epilepsy attending a single centre. Methods: Sixty-four patients (36 men, 28 women, aged 16,65 years) were begun on adjunctive TPM after a 3-month prospective baseline on unchanged medication. Efficacy end points were reached when a consistent response was achieved over a 6-month period at optimal TPM dosing. These were seizure freedom or ,50% seizure reduction (responder). Appetite, behaviour, alertness, and sleep were assessed by caregivers throughout the study. Results: Sixteen (25%) patients became seizure free with adjunctive TPM. There were 29 (45%) responders. A further 10 (16%) patients experiencing a more modest improvement in seizure control continued on treatment at the behest of their family and/or caregivers. TPM was discontinued in the remaining nine (14%) patients, mainly because of side effects. Final TPM doses and plasma concentrations varied widely among the efficacy outcome groups. Many patients responding well to adjunctive TPM did so on ,200 mg daily. Mean carer scores did not worsen with TPM therapy. Conclusions: TPM was effective as add-on therapy in learning-disabled people with difficult-to-control epilepsy. Seizure freedom is a realistic goal in this population. [source]


Focal Ictal , Discharge on Scalp EEG Predicts Excellent Outcome of Frontal Lobe Epilepsy Surgery

EPILEPSIA, Issue 3 2002
Gregory A. Worrell
Summary: ,Purpose: To determine whether a focal ,-frequency discharge at seizure onset on scalp EEG predicts outcome of frontal lobe epilepsy (FLE) surgery. Methods: We identified 54 consecutive patients with intractable FLE who underwent epilepsy surgery between December 1987 and December 1996. A blind review of EEGs and magnetic resonance images (MRIs) was performed. Lesional epilepsy is defined as presence of an underlying structural abnormality on MRI. Results: Overall, 28 (52%) patients were seizure free, with a mean follow-up of 46.5 months. Presence of a focal ,-frequency discharge at seizure onset on scalp EEG predicted seizure-free outcome in lesional (p = 0.02) and nonlesional (p = 0.01) epilepsy patients. At least 90% of patients who had either lesional or nonlesional epilepsy were seizure free if scalp EEG revealed a focal , discharge at ictal onset. Moreover, logistic regression analysis showed that focal ictal , pattern and completeness of lesion resection were independently predictive of seizure-free outcome. Ictal onset with lateralized EEG activity of any kind and postresection electrocorticographic spikes did not predict surgical outcome (p > 0.05). Conclusions: Only about 25% of FLE surgical patients have a focal ,-frequency discharge at seizure onset on scalp EEG. However, its presence is highly predictive of excellent postsurgical seizure control in either lesional or nonlesional FLE surgical patients. [source]


Prognostic Significance of Failure of the Initial Antiepileptic Drug in Children with Absence Epilepsy

EPILEPSIA, Issue 6 2001
Elaine Wirrell
Summary: ,Purpose: In children with childhood absence epilepsy (CAE) and juvenile absence epilepsy (JAE), to determine the impact of failure of initial antiepileptic drug (AED) for lack of efficacy in eventual seizure control and long-term remission of epilepsy. Methods: Centralized EEG records for the province of Nova Scotia allowed identification of all children seen with CAE or JAE between 1977 and 1985. Information regarding success or failure of initial AED in fully controlling seizures and long-term seizure control and remission of epilepsy was collected by patient questionnaire and chart review. Results: Eighty-six of 92 eligible patients were followed up (75 CAE, 11 JAE). Initial AED treatment was successful in 52 (60%) of 86. Success tended to be greater for valproate (VPA) than for other AEDs (p = 0.07), and lower if generalized tonic,clonic or myoclonic seizures coexisted (p < 0.004 and p < 0.03). Terminal remission was more likely if the initial AED was successful than if it had failed (69% vs. 41%; p < 0.02). Compared with those in whom the initial AED was successful, subjects whose initial AED had failed were more likely to progress to juvenile myoclonic epilepsy (JME) at last follow-up (32% vs. 10%; p < 0.02) and to develop intractable epilepsy (17% vs. 2%; p < 0.04). Conclusions: Initial AED was successful in 60% of children with AE. If the first AED failed, the outcome was less favorable, with a lower rate of terminal remission and a higher rate of progression to JME and intractable epilepsy. [source]


Successful Cognitive-Behavioral Habituation Training Toward Photophobia in Photogenic Partial Seizures

EPILEPSIA, Issue 5 2001
Meinolf Noeker
Summary: We report on the cognitive-behavioral treatment of a 12-year-old boy with photogenic partial seizures with secondary generalization who had developed phobic avoidant behavior toward all kinds of situations with potential photostimulation, leading to serious impairments of life quality. Based on a behavioral analysis of seizure and anxiety reaction, a habituation training (systematic desensitization procedure) was developed and performed, while maintaining protection against seizures with antiepileptic pharmacotherapy. The treatment was to gradually increase exposure to computer monitor and television screen photostimulation, closely adjusted to the level of subjective distress and tolerance. In addition to exercising control of photogenic input by regulating the monitor control button, rapid relaxation and imagery techniques were taught and applied as countermeasures at the onset of seizure precipitants. The treatment resulted in complete remission of phobic anxieties and responses and may also have facilitated ongoing seizure control after termination of antiepileptic medication. [source]


Visual Function is Stable in Patients Who Continue Long-Term Vigabatrin Therapy: Implications for Clinical Decision Making

EPILEPSIA, Issue 4 2001
Scott R. Paul
Summary: ,Purpose: Vigabatrin (VGB) has been shown to cause visual field constriction and other forms of mild visual dysfunction. We determined the safety of continuing VGB therapy in patients who had received prolonged treatment (>2 years) with the drug by serially monitoring changes in visual function over a 1-year period of continued therapy. We also followed up patients who discontinued VGB to see whether alternative therapies are effective. Methods: Fifteen of 17 patients who continued VGB therapy had visual-function testing (visual acuity, color vision, kinetic and static perimetry) every 3 months for 1 year. Eighteen patients who discontinued VGB were given alternative antiepileptic drugs (AEDs); their seizure responses were measured after ,3 months of treatment. Results: Patients continuing VGB showed no worsening of visual acuity, color vision, or visual-field constriction beyond that measured in the initial test. Many patients who discontinued VGB had good seizure control with either newer or previously unsuccessful AEDs. Conclusions: For patients who have an excellent response to VGB and only mild visual changes, continued therapy may be safe with close visual monitoring. Patients who do not have a significant reduction in seizures or who experience considerable visual dysfunction with VGB may respond well to alternative therapies. [source]


Effects of Vagus Nerve Stimulation on Progressive Myoclonus Epilepsy of Unverricht-Lundborg Type

EPILEPSIA, Issue 8 2000
Brien Smith
Summary: Purpose: A 34-year-old woman with progressive myoclonus epilepsy of Unverricht-Lundborg type was considered for vagus nerve stimulation (VNS) therapy. Methods: After demonstration of intractability to multiple antiepileptic regimens and progressive deterioration in cerebellar function, the patient was implanted with a vagus nerve stimulator and followed for 1 year. Neurological status, seizure frequency, and parameter changes were analyzed. Results: VNS therapy resulted in reduction of seizures (more than 90%) and a significant improvement in cerebellar function demonstrated on neurological examination. The patient reported improved quality of life based in part on her ability to perform activities of daily living. Conclusions: VNS therapy may be considered a treatment option for progressive myoclonus epilepsy. The effects of VNS on seizure control and cerebellar dysfunction may provide clues to the underlying mechanism(s) of action. [source]


New Insights into the Clinical Management of Partial Epilepsies

EPILEPSIA, Issue S5 2000
Prof. Edouard Hirsch
Summary The diagnosis, treatment, and prognosis of seizure disorders depend on the correct identification of epileptic syndromes. Partial epilepsies are heterogeneous and can be divided into idiopathic, cryptogenic, and symptomatic epilepsies. The most common of the idiopathic localization-related epilepsies is benign epilepsy with rolandic or centrotemporal spikes (BECTS). Seizures remain rare and the use of antiepileptic drug (AED) treatment in all patients does not appear justified. Children who present with some of the electroclinical characteristics of BECTS may also display severe unusual neurologic, neuropsychological, or atypical symptoms. In some cases, carbamazepine has been implicated as a triggering factor. Primary reading epilepsy and idiopathic occipital lobe epilepsies with photosensitivity are examples of an overlap between idiopathic localization-related and generalized epilepsies and respond well to sodium valproate. Autosomal dominant nocturnal frontal lobe epilepsy and benign familial infantile convulsions are recently described syndromes, differing in several ways from classical idiopathic localization-related epileptic syndromes. In cryptogenic or symptomatic epilepsy, the topography of the epileptogenic zone might influence drug efficacy. An individualized approach to AED selection, tailored to each patient's needs, should be used. Resistance of seizures to antiepileptic therapy may be due to diagnostic and/or treatment error or may be the result of noncompliance. Increasing the dosage, discontinuation or replacement of a drug, or addition of a second drug is indicated in truly resistant cases. The use of more than two AEDs rarely optimizes seizure control, and in some cases reduction of treatment may improve seizure control while lessening side effects. EEG-video assessment of patients with refractory epilepsy is important. Indications for and timing of epilepsy surgery should be reconsidered. Surgical therapy should probably be used more often and earlier than it is at present. [source]


Febrile Seizures: Treatment and Prognosis

EPILEPSIA, Issue 1 2000
Finn Ursin Knudsen
Summary: Recent epidemiologic data indicate that the vast majority of children with febrile seizures have a normal long-term outcome. A precise knowledge of the short- and long-term outcome with or without treatment, and short- and long-term side effects is an important prerequisite for assessing the various treatment strategies. We focus on the impact of short-term or prophylactic treatment on the short- and long-term outcome of various types of febrile seizures. There is universal agreement that daily prophylaxis with antiepileptic agents should never be used routinely in simple febrile seizures, but only in highly selected cases, if at all. Intermittent diazepam (DZP) prophylaxis at times of fever may or may not reduce the recurrence rate, but it does not appear to improve the long-term outcome as compared with short-term seizure control. The treatment may be used to reduce the recurrence rate for a small arbitrarily defined group with multiple simple febrile seizures, complex febrile seizures, especially focal, prolonged or both, febrile status, and when parental anxiety is severe. However, there is no evidence that treatment of simple febrile seizures can prevent the rare cases of later epilepsy, and many children with complex febrile seizures have a benign long-term outcome, even without treatment. Many prefer a "wait and see" policy. An attractive alternative is to treat new febrile seizures with rectal DZP in solution at seizure onset, given by the parents at home to prevent febrile status. Newer, less well documented short-term strategies include nasal, oral, or rectal administration of other benzodiazepines. Short-term seizure control of febrile status and careful parental counseling are the two most important targets of treatment. [source]