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Secondary Generalization (secondary + generalization)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

Intrinsic Ictal Dynamics at the Seizure Focus: Effects of Secondary Generalization Revealed by Complexity Measures

EPILEPSIA, Issue 2 2007
Christophe C. Jouny
Summary:,Purpose: Partial seizures (PSs) may be self-limited regional events or propagate further and secondarily generalize. The mechanisms and dynamics of secondarily generalized tonic,clonic seizures (GTCSs) are not well understood. Methods with which to assess the dynamic of those events are also limited. Methods: Seizures were analyzed from patients with intractable partial seizures undergoing monitoring with intracranial electrodes. Inclusion in this study required patients to have at least one PS and one GTCS. From >120 patients, seven patients fulfilled these criteria, three with mesial temporal (MTLE) onset seizures and four with neocortical lesional (NCLE) onset seizures. In total, 50 seizures were analyzed by using the matching pursuit (MP) method and the Gabor atom density (GAD), a measure of signal complexity derived from the MP method. Results: The GAD complexity pattern at the seizure focus for the initial ictal period is remarkably consistent in a given patient, regardless of whether secondary generalization occurs. Secondary generalization produces greater modification of seizure activity at the focus in patients with NCLE than in patients with MTLE. In seizures from four patients with NCLE, secondary generalization resulted in an average increase of 115% in complexity at the focus compared to PSs. Conclusions: GAD shows that seizure dynamics of PSs are often very stereotyped from seizure to seizure in a given patient, particularly during early ictal evolution. Secondary generalization is more likely to produce changes in the duration and dynamics at the seizure focus in NCLE patients compared with MTLE patients. These observations suggest distinct mechanisms (e.g., feedback) that are operational during secondary generalization. [source]

Contrasting Effects of Zonisamide and Acetazolamide on Amygdaloid Kindling in Rats

EPILEPSIA, Issue 11 2001
Koichi Hamada
Summary: ,Purpose: Zonisamide (ZNS) and acetazolamide (AZM) are two antiepileptic drugs (AEDs) that differ in clinical efficacy. To elucidate the mechanisms of action of these compounds, we investigated their therapeutic and prophylactic effects in rats by using a kindling model of partial epilepsy. Methods: Electrodes were implanted into the left amygdala of adult male Wistar rats. The animals were stimulated at the afterdischarge threshold until five stage 5 seizures were induced. The generalized seizure threshold was then determined. Therapeutic effects were examined in rats manifesting successive convulsions with near-threshold stimulation. To test prophylactic effects, drugs were administered intraperitoneally before daily kindling stimulation until the animal had a stage 5 seizure or reached day 18. Results: ZNS (10,40 mg/kg; n = 6) suppressed kindled seizures in a dose-dependent manner. Repeated administration for 7 days produced tolerance to anticonvulsive effects. AZM (25,200 mg/kg; n = 7) showed limited therapeutic effect, alleviating only the clonic convulsion in stage 5 seizures and reducing afterdischarge duration. Secondary generalization was not significantly suppressed during repeated treatment (50,200 mg/kg; n = 6). ZNS, 25 or 40 mg/kg (n = 8), significantly retarded seizure development; 15.0 or 17.0 daily stimulations were required to produce a stage 5 seizure. AZM, 50,200 mg/kg (n = 6), also retarded seizure development, with 14.0,14.8 stimulations required. Conclusions: ZNS exhibited modest therapeutic and prophylactic effects, whereas AZM showed mainly prophylactic effects. Hypotheses are presented that may explain the mechanisms of action of these drugs. [source]

Baseline cognition, behavior, and motor skills in children with new-onset, idiopathic epilepsy

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 1 2010
VIKRAM V BHISE
Aim, Epilepsy is associated with difficulties in cognition and behavior in children. These problems have been attributed to genetics, ongoing seizures, psychosocial issues, underlying abnormality of the brain, and/or antiepileptic drugs. In a previous study, we found baseline cognitive differences between children with partial versus generalized and convulsive versus non-convulsive seizures. Measures in that study focused primarily on IQ scores. In the present study, we assessed baseline function with respect to new learning, attention, and memory, thus providing a more comprehensive profile than our previous study. Method, We examined 57 children (42 females, 15 males), aged 6 to 17 years (mean 10y 1mo, SD 2y 9mo), with new-onset, idiopathic epilepsy, using tests of cognitive function reflective of new learning, memory, and attention. Seizures were classified as generalized convulsive (n=5), generalized non-convulsive (n=18), or focal (n=34). Focal seizures were divided into unilateral versus bilateral independent foci, and presence versus absence of secondary generalization. Results, Attention was a particular area of weakness across all groups. The Vocabulary score of an intelligence screen was higher for the focal seizure groups (p=0.012), primarily because of a difference between the unilateral focal and the primary generalized groups (p<0.047). Children with generalized, non-convulsive seizures performed significantly worse than the focal group on a measure of short-term auditory memory (p=0.019). All groups performed poorly on a test of visual,motor speed. Interpretation, These findings suggest intrinsic abnormalities in children with new-onset, idiopathic epilepsy at baseline. [source]

Adjunctive lacosamide for partial-onset seizures: Efficacy and safety results from a randomized controlled trial

EPILEPSIA, Issue 3 2009
Péter Halász
Summary Purpose:, To evaluate the efficacy and safety of lacosamide (200 and 400 mg/day) when added to one to three concomitant antiepileptic drugs (AEDs) in patients with uncontrolled partial-onset seizures. Methods:, This multicenter, double-blind, placebo-controlled trial randomized patients (age 16,70 years) with partial-onset seizures with or without secondary generalization to placebo, lacosamide 200, or lacosamide 400 mg/day. The trial consisted of an 8-week baseline, a 4-week titration, and a 12-week maintenance period. Results:, Four hundred eighty-five patients were randomized and received trial medication. Among these, 87% were taking two or more concomitant AEDs. Median percent reduction in seizure frequency per 28 days from baseline to maintenance period (intent-to-treat, ITT) was 20.5% for placebo, 35.3% for lacosamide 200 mg/day (p = 0.02), and 36.4% for 400 mg/day (p = 0.03). In the per protocol population, the reductions were 35.3% for lacosamide 200 mg/day (p = 0.04) and 44.9% for 400 mg/day (p = 0.01) compared to placebo (25.4%). The 50% responder rate for lacosamide 400 mg/day (40.5%) was significant (p = 0.01) over placebo (25.8%), but was not for 200 mg/day (35.0%). In the per protocol population, the 50% responder rate for lacosamide 400 mg/day (46.3%) was significant (p < 0.01) compared with the placebo responder rate (27.5%). Dose-related adverse events (AEs) included dizziness, nausea, and vomiting. Clinically relevant changes in the mean plasma concentrations of commonly used AEDs were not observed. Discussion:, Results of this trial demonstrated the efficacy and tolerability of adjunctive lacosamide 200 and 400 mg/day and support that lacosamide may be an advantageous option for the treatment of partial-onset seizures in patients with epilepsy. [source]

Intrinsic Ictal Dynamics at the Seizure Focus: Effects of Secondary Generalization Revealed by Complexity Measures

Epilepsy in Colombia: Epidemiologic Profile and Classification of Epileptic Seizures and Syndromes

EPILEPSIA, Issue 1 2006
Alberto Velez
Summary:,Purpose: A national study was performed in Colombia to determine the general and regional prevalence of epilepsy, clinical profiles, seizure types, and clinical syndromes. Methods: Based on the National Epidemiological Study of Neurological Diseases (EPINEURO), we evaluated and followed up for 1 year all the subjects with epilepsy from the National Sample. Clinical profiles were further assessed. Seizure types and epilepsy syndromes were established according to the international classifications. Results: General prevalence was found to be 11.3 per 1,000, with little variation among regions, except the eastern region, where prevalence was 23 per 1,000; prevalence for active epilepsy was 10.1 per 1,000. Women have a slightly greater (not statistically significant) risk. Most seizures are focal (partial), frequently with secondary generalization. The most frequent epilepsy syndrome encountered was partial symptomatic/cryptogenic (80%). Epilepsy onset in Colombia occurs most frequently in childhood. Conclusions: Prevalence rates of epilepsy in Colombia are similar to those reported in nations with comparable developmental status and have diminished over time. The study presents the distribution of seizures and syndromes. The most frequent types are focal syndromes. [source]

Cortical Resection with Electrocorticography for Intractable Porencephaly-related Partial Epilepsy

EPILEPSIA, Issue 1 2005
Koji Iida
Summary:,Purpose: We evaluated the results of cortical resection of epileptogenic tissue for treatment of intractable porencephaly-related epilepsy. Methods: We examined clinical features, electrophysiological data, surgical findings, and seizure outcomes after cortical resection in eight patients with intractable epilepsy related to porencephalic cysts. Results: All eight patients had hemiparesis. Five retained motor function in the hemiparetic extremities; six retained visual fields. All had partial seizures, six with secondary generalization. Seven patients had simple and three had complex partial seizures (CPSs); two also had drop attacks. Four patients had multiple seizure types. Long-term scalp video-EEG (LVEEG) localized interictal epileptic abnormalities that anatomically corresponded to the cyst location in three patients. LVEEG recorded ictal-onset zones in five; these anatomically corresponded to the cyst location in three of the five. EEG recorded generalized seizures in two patients, hemispheric in one, and multifocal in two. Intraoperative electrocorticography (ECoG) revealed interictal epileptic areas extending beyond the margins of the cyst in seven patients. We resected ECoG-localized interictal epileptic areas completely in five patients and partially in two. Cortical resection was based on seizure semiology and LVEEG in one patient whose ECoG showed no epileptiform discharges. After a minimum follow-up of 1 year, six patients had excellent seizure outcome (Engel class I), and two had a >90% seizure reduction (Engel class III) without complications. Conclusions: Cortical resection guided by ECoG allows preservation of motor function and visual field and provides an effective surgical procedure for treatment of intractable epilepsy secondary to porencephaly. [source]

Resistance to Propagation of Amygdaloid Kindling Seizures in Rats with Genetic Absence Epilepsy

EPILEPSIA, Issue 10 2002
Esat E, kazan
Summary: ,Purpose: The existence of absence epilepsy and temporal partial seizure pattern in the same patient is an uncommon state. In the present study, we aimed to evaluate whether the process of kindling as a model of complex partial seizures with secondary generalization is altered in rats with genetic absence epilepsy. Methods: Six- to 12-month-old nonepileptic control Wistar rats and genetic absence epileptic rats from Strasbourg (GAERS) were used in the experiments. One week before the experiments, bilateral stimulation and recording electrodes were implanted stereotaxically into the basolateral amygdala and cortex, respectively. Animals were stimulated at their afterdischarge threshold current twice daily for the process of kindling and accepted as fully kindled after the occurrence of five grade 5 seizures. Bilateral EEGs from amygdala and cortex were recorded continuously during 20 min before and 40 min after each stimulus. Results: All control Wistar rats were fully kindled after stimulus 12 to 15. Although the maximal number of stimulations had been applied, GAERS remained at stage 2, and no motor seizures were observed. The afterdischarge duration in bilateral amygdala and the cortex after the kindling stimulus was shorter in GAERS when compared with control rats. Conclusions: Occurrence of only grade 2 seizures and no observation of grade 3,5 seizures in GAERS with the maximal number of stimulations would suggest that the generalized absence seizures may be the reason of the resistance in the secondary generalization of limbic seizures during amygdala kindling. [source]

Tooth Brushing,Induced Seizures: A Case Report

EPILEPSIA, Issue 5 2001
Michael Koutroumanidis
Summary: We report a 28-year-old woman of normal intellect, who had three late-onset seizures with unusual ictal features and secondary generalization during prolonged and vigorous tooth brushing. Neurologic examination and brain magnetic resonance imaging (MRI) were normal, but interictal EEG showed left frontal epileptiform activity. Reasonable precautions (regular but briefer and less vigorous brushing of her teeth) combined with a moderate dose of carbamazepine effectively prevented seizure recurrence. This case may be an example of cryptogenic form of reflex epilepsy with seizures induced exclusively by tooth brushing. [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]

Postictal Central Apnea as a Cause of SUDEP: Evidence From Near-SUDEP Incident

EPILEPSIA, Issue 11 2000
Elson L. So
Summary: While undergoing video-EEG monitoring, a 20-year-old woman had a 56-second convulsive seizure, after which she developed persistent apnea. The rhythm of the electrocardiogram complexes was unimpaired for approximately 10 seconds, after which it gradually and progressively slowed until it stopped 57 seconds later. Evaluation after successful cardiorespiratory resuscitation showed no evidence of airway obstruction or pulmonary edema. The patient had a previous cardio-respiratory arrest after a complex partial seizure without secondary generalization. Although epileptic seizures are known to be potentially arrhythmogenic to the heart, our observations strongly suggest that one probable mechanism of sudden unexplained death in epilepsy is the marked central suppression of respiratory activity after seizures. [source]

Epilepsy Can Be Diagnosed When the First Two Seizures Occur on the Same Day

EPILEPSIA, Issue 9 2000
Peter Camfield
Summary: Purpose: Experts have suggested that when the first two (or more) unprovoked seizures occur on the same day, they should be considered as a single event and the diagnosis of epilepsy await a further seizure. We have studied the subsequent clinical course of children with their first two seizures on the same day ("same day" group) compared with children with their first two seizures separated by more than one day ("different day" group). Method: The Nova Scotia childhood epilepsy database documented all newly diagnosed children with epilepsy from 1977 to 1985 with follow-up in 1990 and 1991. Epilepsy was defined as two or more unprovoked seizures regardless of the interval between seizures provided that consciousness fully returned between seizures. All patients had their first seizure between the ages of 1 month and 16 years. Seizure types were restricted to partial, generalized tonic-clonic, and partial with secondary generalization. Results: Of the 490 children with partial or generalized tonic-clonic seizures and follow-up of more than 2 years, 70 had their first two or more seizures on the same day and 420 had their first two seizures on different days. Eighty percent (56 of 70) of the "same day" group subsequently had one or more further seizures with (n = 14) or without (n = 42) medication; 80.9% (340 of 420) of the "different day" group had one or more further seizures with (n = 115) or without (n = 225) medication. Seizure types were nearly identical. Cause was the same (except for fewer idiopathic "genetic" cases in the "same day" group: 1 of 70 vs. 42 of 420; p = 0.02). Rates of mental handicap and previous febrile seizures were the same. Children in the "same day" group were younger on average (60 vs. 84 months; p = 0.001) and were somewhat more likely to have neurological impairment. Outcome after 7 years average follow-up was the same: 58% of the "same day" group and 56% of the "different day" group were in remission. Conclusion: If two or more unprovoked seizures (with normal consciousness between) occur on the same day, the child appears to have epilepsy and will have a clinical course identical to that of the child with a longer time interval between the first two seizures. [source]

Defining success in clinical trials , profiling pregabalin, the newest AED

EUROPEAN JOURNAL OF NEUROLOGY, Issue 2005
P. Ryvlin
The efficacy and safety of pregabalin as adjunctive therapy for patients with partial epilepsy with or without secondary generalization has been established by four randomized, 12-week, double-blind, placebo-controlled trials (n = 1396) and four long-term open-label studies (n = 1480). Patients in the three fixed-dose trials were ,12 years of age, had ,6 partial seizures and no 4-week seizure-free period during the 8-week baseline period. Seventy-three per cent of patients were taking ,2 concomitant antiepileptic drugs. Responder rates across the effective doses (150,600 mg/day) ranged from 14% to 51% and demonstrated a significant dose,response relationship. The most common adverse events were central nervous system related, generally mild or moderate, transient, and tended to be dose related. The fourth placebo-controlled trial compared a fixed dose of pregabalin 600 mg/day with a flexible-dose regimen (150,600 mg/day). Responder rates were greater for both the fixed dose (45.3%, P < 0.001) and flexible dose (31.3%, P < 0.001) when compared with placebo (11.0%). Compared with the fixed-dose group, the flexible-dose patients had a lower incidence of adverse events and study discontinuations. In long-term open-label trials, the efficacy of pregabalin was maintained with respect to 50% responder rates suggesting no obvious tolerance developing over 2 years. Seizure-free rates were 8.9% and 5.8% for the last 6 months and 1 year of pregabalin treatment, respectively. Long-term open-label pregabalin treatment was well tolerated. [source]

Application of a vagal nerve stimulator in an epilepsy patient with cardiac pacemaker after post-ictal cardiac arrest

ACTA NEUROLOGICA SCANDINAVICA, Issue 2 2009
R. Cáceres
In this case report we present a patient with temporal lobe epilepsy (TLE) showing partial complex seizures and secondary generalization, and treated with several antiepileptic drugs. After two consecutive seizures she had an episode of cardiac arrest followed by AV-block III which led to the implantation of a cardiac pacemaker. She subsequently received a vagal nerve stimulator because of poor response to epilepsy treatment. Combined treatment with two different electromagnetic stimulators raises the question of safety during surgery which is discussed. [source]

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]