bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Complete and Partial Bilateral Lesions of the Deep Cerebellar Nuclei on Amygdaloid Kindling in Rats
Authors: Min Jason K. , Valentine Pamela A. , Teskey G. Campbell 
Published: August 2005

Summary: Purpose: The roles of the deep cerebellar nuclei in epileptogenesis and seizure expression are not well defined. To determine their properties, we examined the effects of lesions to the dentate, fastigial, and interpositus nuclei in adult rats that were electrically kindled in the amygdaloid complex. Changes in afterdischarge duration (ADD) as well as the expression and progression of behavioral seizures to fully generalized tonic‐clonic convulsions (stage 5) were assessed. Methods: Fifty rats first underwent bilateral electrolytic lesions of either the dentate, fastigial, or interpositus nuclei. After a 7–day recovery period, they were kindled daily until they manifested two stage 5 convulsions. Careful histological examination was used to determine lesion extent. Results: When the dentate or fastigial nucleus was completely destroyed on the side contralateral to the stimulated amygdala, fewer stimulations were required to produce stage 5 seizures and latencies to the expression of forelimb clonus were shorter, as were ADD. On the other hand, when the dentate or fastigial neucleus was only partly obliterated on the contralateral side, more stimulations were required to produce stage 5 seizures and ADD was longer. Neither complete nor partial lesions of the interpositus nuclei had any effect on the number of stimulations to reach a stage 5 seizure, latency to the expression of clonus, or ADD. Conclusions: Our findings suggest that the dentate and fastigial nuclei, but not the interpositus nuclei, may normally retard epileptogenesis and inhibit clonic behaviors, but paradoxically may facilitate ADD.
Epilepsy Surgery in the First Three Years of Life
Authors: Duchowny M. , Jayakar P. , Resnick T. , Harvey A. S. , Alvarez L. , Dean P. , Gilman J. , Yaylali I. , Morrison G. , Prats A. , Altman N. , Birchansky S. , Bruce J. 
Published: August 2005

Summary: Purpose: Partial seizures in early postnatal life may be catastrophic and associated with poor long‐term outcome. Epilepsy surgery can alleviate partial seizures in older children and adults, but there is little experience with surgical therapy in infancy apart from hemispheric epilepsy syndromes. Methods: We analyzed the results of cortical resection to treat medically refractory partial epilepsy in 31 children (16 boys, 15 girls) aged <3 years (mean, 18.3 months). Subjects were included only if seizure relief was the primary indication for surgery. Results: Follow‐up of at least 1 year (mean, 4.6 years) in 26 patients revealed that 16 were seizure‐free, 4 had >90% seizure reduction, and 6 had <90% reduction. There was no significant difference in seizure outcome between hemispherectomy/multilobar resections and lobar resections or temporal versus extratemporal resection. Seizure outcome was independent of the amount of cortex removed in nonlesional patients. Only the presence of a discrete lesion on preoperative neuroimaging correlated with a favorable outcome. Family perceptions of accelerated development in seizure‐free patients were not confirmed on developmental assessment. Conclusions: We conclude that cortical resection often benefits very young children with catastrophic partial seizures, but does not guarantee enhanced neurological development. The location and extent of the excised cortex may not be critical as long as the entire epileptogenic region and tesion are removed.
Intractable Epilepsy in a Population‐Based Series of Mentally Retarded Children
Authors: Steffenburg Ulf , Hedström Anders , Lindroth Anne , Wiklund Lars‐Martin , Hagberg Gudrun , Kyllerman Mårten 
Published: August 2005

Summary: Purpose: The characteristics of intractable epilepsy were analyzed in a population‐based study of active epilepsy in mentally retarded children aged 6–13 years. Methods: Diagnostic registers, EEG laboratory registers, and registers for the Education of the Subnormal were searched. Medical files were scrutinized. Clinical examinations and interviews with parents and caregivers or both were performed. EEG recordings, computed tomography (CT) and magnetic resonance imaging (MRI) of the CNS were reevaluated. Results: Forty‐five percent (44 of 98) of the children with mental retardation (MR) and active epilepsy had intractable seizures, defined as one or more seizures every day or week. The median age at onset was 0.8 years, as compared with 3.0 years for those with controlled epilepsy. Predictive factors for frequent seizures were the number of seizure types, severe MR, status epilepticus (SE) and tonic seizures. Epileptiform EEG activity was present in 91%, and focal activity in 65%. Brain lesions were detected on CT and MRI in 70%, with generalized lesions in 60%. Concurrent focal epileptiform activity and focal brain lesions on CTIMRI were detected in 26%. The percentages and prevalence rates for infantile spasms (IS) and Lennox‐Gastaut syndrome (LGS) were 18% (0.25 in 1,000) and 7% (0.06 in 1,000), respectively. One of 8 children with IS had had previous neonatal seizures, 3 had SE and 1 later developed LGS. Conclusions: Children with MR and intractable epilepsy have a high frequency of severe MR and additional major neuroimpairments. EEG recordings frequently showed focal changes despite generalized lesions in neuroradiology.
Continuous Unilateral Epileptiform Discharge and Language Delay: Effect of Functional Hemispherectomy on Language Acquisition
Authors: Rosenblatt Bernard , Vernet Olivier , Montes Jose L. , Andermann Frederick , Schwartz Sybil , Taylor Laughlin B. , Villemure Jean‐Guy , Farmer Jean‐Pierre 
Published: August 2005

Summary: Purpose: To assess the efficacy of functional hemispherectomy in promoting language acquisition in a child with severe language delay and continuous left hemispheric epileptiform discharge in the absence of clinical seizures. We report a 6‐month‐old girl who initially presented with a right hemiparesis secondary to a lesion of probable prenatal origin in the distribution of the left middle cerebral artery. Weeks later, she developed infantile spasms. At 1.5 years of age, because of intractable seizures, the patient had fenestration of the left porencephalic cyst and anterior temporal lobectomy. The seizures ceased; however, language development remained limited to 35 words at 3.5 years of age. The EEG showed almost continuous epileptiform activity over the left hemisphere with no independent epileptiform potentials contralaterally. She underwent a functional left hemispherectomy. Methods: Imaging, electroencephalographic investigation, pre‐ and postoperative psychological and speech assessment were carried out. Results: Considerable language, speech, and behavior improvement was noted within 2 months of surgery. Conclusions: Interictal epileptiform discharges can interfere with the development of contralateral hemispheric function in the absence of clinical seizures. Early functional hemispherectomy may have a role in promoting optimal language development in appropriately selected patients. Although the primary indication for functional hemispherectomy is to control intractable seizures, a secondary proposed indication is to reduce functional impairment of the other hemisphere by electrical interference.
Effects of Tiagabine Monotherapy on Abilities, Adjustment, and Mood
Authors: Dodrill Carl B. , Arnett John L. , Shu Vincent , Pixton Glenn C. , Lenz Gregory T. , Sommerville Kenneth W. 
Published: August 2005

Summary: Purpose: We evaluated the dose‐related impacts of tiagabine (TGB) on cognition and mood in a monotherapy study. Methods: Patients were 123 adults with uncontrolled partial seizures, each treated with a single currently available antiepileptic drug (AED) for management of clinical epilepsy. They completed a battery of neuropsychological tests during an 8 week prospective baseline period and once again at the end of the 12‐week fixed‐dose period (or earlier if they dropped out of the study). Sixty‐six patients were randomized to 6 mg/day TGB and 57 were randomized to 36 mg/day TGB. Results: Few changes in either abilities or adjustment and mood were noted when all patients were considered as a single group. However, analysis of both dose and attainment of TGB monotherapy showed that patients receiving TGB monotherapy did best, improving particularly in the areas of adjustment and mood with low‐dose TGB and in the area of abilities with high‐dose TGB. Patients who did not attain monotherapy showed no change except that the high‐dose group did not perform as well on measures of mood and adjustment. Baseline AED and changes in seizure control did not affect the results. Conclusions: Patients attainment of TGB monotherapy was associated with their achievement of positive changes of varying degree on psychological tests. Failure to attain TGB monotherapy was associated with no changes on the tests except in patients receiving high‐dose TGB where it appeared that some alterations in mood might have been avoided if a slower titration schedule had been used.
Predicting Outcome of Anterior Temporal Lobectomy Using Simulated Neural Networks
Authors: Grigsby Jim , Kramer Ronald E. , Schneiders Jay L. , Gates John R. , Brewster Smith W. 
Published: August 2005

Summary: Purpose: Anterior temporal lobectomy (ATL) is an important option for treatment of medically refractory seizures. Patient selection is not always clear‐cut, and there is inherent morbidity and mortality associated with the invasive and expensive surgical protocols. To determine whether patient selection might be facilitated by application of artifical intelligence, we developed a model that predicted seizure outcome after ATL, using a simulated neural network (SNN). Methods: Predictions of the model were compared with predictions derived from conventional discriminant function analysis. Neural networks and discriminant functions were devised that would predict the occurrence of both Class 1 out‐comes (totally seizure‐free), and Class 1 or Class 2 outcomes (nearly or totally seizure‐free), using data from 87 patients from three surgical centers. The SNNs and discriminant functions were developed using data from a randomly selected subsample of 65 patients, and both models were cross‐validated, using the remaining 22 patients. Results: The discriminant functions showed overall predictive accuracy of 78.5% and 72.7%, while the neural networks demonstrated overall accuracy of 81.8 and 95.4%. Conclusions: Simulated neural networks show promise as adjuncts to decision‐making in the selection of epilepsy surgery patients.
Startle Epilepsy with Infantile Hemiplegia: Report of Two Cases Improved by Surgery
Authors: Oguni Hirokazu , Hayashi Kitami , Usui Norihisa , Osawa Makiko , Shimizu Hiroyuki 
Published: August 2005

Summary: Purpose: To study the effectiveness of surgical therapy on 2 patients with startle epilepsy with infantile brain damage (SEIBD), a rare but distinctive epileptic syndrome characterized by motor seizures resistant to antiepileptic drugs (AEDs). Methods: The patients with SEIBD both had hemiplegia, due to gross contralateral hemispheric lesions, and suffered from tonic postural seizures, frequently provoked by sudden unexpected somatosensory stimuli on the paretic side of the body. These attacks occasionally caused the patients to drop to the floor, and mild‐to‐moderate injuries had been sustained; they were resistant to all currently available AEDs. Consequently, these daily drop attacks severely restricted the patients' social lives and school participation. Both patients underwent corpus callosotomy and resection of epileptogenic premotor and supplementary motor lesions. One patient also underwent additional multiple subpial transections of the primary sensorimotor area. Results: Seizures, as well as quality of life, improved dramatically in both patients after surgery. Conclusions: Startle epilepsy with infantile hemiplegia is distinct epileptic syndrome characterized by structural brain damage restricted primarily to one hemisphere, large ipsilateral epileptogenic lesions involving the perisensorimotor area, refractory startle‐provoked drop attacks, and a good response to epilepsy surgery.
Influence of an Evacuation in February 1995 in The Netherlands on the Seizure Frequency in Patients with Epilepsy: A Controlled Study
Authors: Swinkels W. A. M. , Engelsman M. , Kasteleijn‐Nolst Trenité D. G. A. , Baal M. G. , De Haan G. J. , Oosting J. 
Published: August 2005

Summary: Purpose: Stress is often noted by patients to be a precipitating factor in causing seizures. No precise data are, however, available. In 1995 for 250,000 inhabitants in the Netherlands, a serious life event occurred within a period of seven days. An extreme high water level in the province of Gelderland, with the possibility of a flood, made the government decide to evacuate people and their livestock. This retrospective study investigated the influence of this forced evacuation on the seizure frequency of patients with epilepsy, compared with patients of the same age and type of epilepsy living outside the evacuation area at the time of the threatening flood. Methods: Information regarding epilepsy syndrome, seizure type, and frequency was derived from seizure diaries and medical histories of 30 evacuated patients and 30 matched control patients. Results: Of the 30 evacuees, eight showed an increase and one a decrease in seizure frequency during or shortly after the evacuation period, compared with one and zero control patients, respectively. These results proved to be statistically significant (p < 0.05). Conclusions: Our data support the hypothesis that there is a relation, albeit small, between a stressful life event and seizure frequency.
Electrophysiologic Analysis of the Actions of Valproate on Pyramidal Neurons in the Rat Hippocampal Slice
Authors: Albus H. , Williamson R. 
Published: August 2005

Summary: Purpose: Studies in invertebrates and cultured mammalian neurons suggested that valproate (VPA) mediates its main antiepileptic effect by slowing the recovery from inactivation of voltage‐dependent sodium channels. This predicts an effect on the refractory period of the action potential and, consequently, on the bursting behavior of neurons. Methods: We investigated this prediction using intracellular and extracellular recording techniques in hippocampal slices prepared from adult rats. The refractory period (RFP) and the ratio of the slopes (SR) of a pair of action potentials were used as indices of the recovery from inactivation of sodium channels. They were measured by injecting a series of paired depolarizing current pulses into CAI pyramidal neurons. Results: No significant changes were observed in the RFP or SR measured during a I‐h recording period when VPA was bath‐applied (1 mM), or when it was present in the recording electrode (10–50 mM). Lowering the temperature from 34.5°C to 26.4°C resulted in an increase of the RFP by 100% and a decrease of the SR by 40%. However, VPA did not affect any of the measured action potential parameters at this lower temperature. VPA was also without effect on the presynaptic fiber volley of axons recorded extracellularly in the stratum radiatum. The antidromic population spike was unaffected by VPA (2 mM), whereas phenytoin (50 μM) clearly affected this spike in the same slices. The absence of effect of VPA on each of the measured parameters could not be attributed to poor penetration through the slice because bath‐applied VPA reduced the frequency of extracellularly recorded spontaneous interictal bursts, induced by bicuculline and elevated K+, within 10 min. Conclusions: These findings suggest that at least in the hippocampal slice the drug's principal antiepileptic effect cannot be explained by its action on voltage‐dependent sodium channels.
MRS Metabolic Markers of Seizures and Seizure‐Induced Neuronal Damage
Authors: Najm I. M. , Wang Y. , Shedid D. , Lüders H. O. , Ng T. C. , Comair Y. G. 
Published: August 2005

Summary: Purpose: Proton magnetic resonance spectroscopy (MRS) was used to identify specific in situ metabolic markers for seizures and seizure‐induced neuronal damage. Kainic acid (KA)‐induced seizures lead to histopathologic changes in rat brain. The protective effect of cycloheximide treatment against neuronal damage caused by KA‐induced seizures was studied, using in situ proton MRS imaging technique. Methods: Rats were pretreated with placebo or cycloheximide 1 h before KA injection. Rat brains (n = 25) were scanned at the level of the hippocampus before, during, and 24 h after seizures. Spectra were recorded and the relative ratios of N‐acetylaspartate (NAA), choline (cho), and lactate (Lac) to creatine (Cr) were calculated and compared between groups. Results: A significant increase in Lac ratios was observed in KA‐treated rats during and 24 h after seizure onset and this increase was prevented by cycloheximide pretreatment. NAA ratios were significantly higher during the ictal phase following KA treatment and this effect was not affected by cycloheximide pretreatment. Nissl staining confirmed previously reported prevention of KA‐induced neuronal loss in CA1 and CA areas of the hippocampus by cycloheximide pretreatment. Conclusions: Our results suggest that in situ Lac increase is a marker of seizure‐induced neuronal damage, whereas N‐acetylaspartate (NAA) changes during and after status epilepticus may be a reflection of neuronal activity and damage, respectively.
Contribution of Neuropsychological Data to the Prediction of Temporal Lobe Epilepsy Surgery Outcome
Authors: Sawrie Stephen M. , Martin Roy C. , Gilliam Frank G. , Roth David L. , Faught Edward , Kuzniecky Ruben 
Published: August 2005

Summary: Purpose: We empirically examined the contribution of neuropsychological data to the prediction of postoperative seizure control relative to base rate information in an existing series of patients undergoing anterior temporal lobectomy (ATL). Methods: A discriminant function predicting surgery outcome (seizure‐free vs. non‐seizure‐free) was computed separately for samples of patients with left (n = 79) and right (n = 62) temporal lobectomy (LATL, RATL). Predictor variables included 14 measures tapping five neurocognitive domains. The predicted base rates were compared with the actual base rates in the two samples. Finally, overall predictive accuracy was examined in optimal versus suboptimal ATL patients. Results: The base rate of seizure freedom in the LATL group was 74.70%; that in the RATL group was 66.10%. The predictive function for the LATL group achieved a hit rate of 80.00% and a positive predictive power of 92.1 1%. The function for the RATL group achieved a hit rate of 83.33% and a positive predictive power (PPP) of 89.66%. The overall predictive accuracy for the optimal group was only 55%, but that in the suboptimal group was 72%. Conclusions: Neuropsychological data used in a multivariate statistical fashion may be able to offer an incremental increase in the prediction of postoperative seizure freedom relative to existing base rates of surgery success in patients with ATL epilepsy. The use of neuropsychological data may be of greatest predictive value in a population of ATL candidates with suboptimal findings with a lower base rate of postoperative seizure freedom, but may actually reduce predictive accuracy in a group of ATL candidates from an optimal population with an already high base rate of surgical success.
Naming Decline After Left Anterior Temporal Lobectomy Correlates with Pathological Status of Resected Hippocampus
Authors: Davies Keith G. , Bell Brian D. , Bush Andrew J. , Hermann Bruce P. , Curtis Dohan F. , Jaap Amy S. 
Published: August 2005

Summary:Purpose:To evaluate the determinants of postoperative change in visual confrontation naming ability and the differential sensitivity of two common tests of confrontation naming.Methods:In a group of 99 patients undergoing lobectomy of the left, language‐dominant anterior temporal lobe, we examined naming ability using two measures: the 60 item Boston Naming Test (BNT), and the Visual Naming (VN) subtest of the Multilingual Aphasia Examination (MAE). ATL entailed resection of lateral temporal lobe followed by microsurgical complete removal of hippocampus. Language mapping was not performed. The status of the resected hippocampus was graded on a scale 0–4 of hippocampal sclerosis (HS). A dichotomous grouping HS‐ (grades 0 and 1, n = 34) and HS+ (grades 3 and 4, n = 61) was effected. Age at surgery, age of epilepsy onset, sex, extent of lateral temporal resection, Full‐Scale IQ (FSIQ), and preoperative naming scores were also examined as potential predictors of pre‐ versus postoperative naming change.Results:Preoperative BNT and VN scores were significantly worse for HS+ than for HS‐ (BNT, p c 0.05; VN, p = 0.001). Postoperatively, BNT and VN scores significantly declined for HS‐ as compared with HS+ patients (p c 0.001). For individual risk, the 90th centile of reliable change index (RCI) was used. By this criterion, of the total sample, 39% evidenced decline on the BNT and 17% evidenced decline on the VN. Logistic regression analysis with backward elimination showed HS to be the only predictor of decline in BNT and HS and sex to be the only predictors of VN decline. Males were more at risk than females. Age, age at onset, extent of lateral resection, preoperative scores, and FSIQ were not predictors. Using age at onset as a proxy for HS+/HS‐ we calculated probabilities for naming decline for given onset age.Conclusions:Both preoperative and postoperative change in naming ability are associated with the pathological status of the hippocampus. The potential interpretations and implications of these findings are discussed.
Visual and Automatic Investigation of Epileptiform Spikes in Intracranial EEG Recordings
Authors: Dümpelmann M. , Elger C. E. 
Published: August 2005

Summary: Purpose: Performance of automatic spike‐detection algorithms and interrater reliability of human EEG reviewers were investigated previously by using scalp EEG recordings. However, it is not known, whether the findings of these studies hold for intracranial recordings. To address this question, we analyzed spike detection in intracranial recordings by two human reviewers and three automatic systems covering major lines in the development of automatic spike‐detection systems. Methods: Intracranial recordings from subdural and intrahippocampal depth electrode contacts in seven patients were analyzed by two reviewers and three spike‐detection systems: (a) The rule‐based system by Gotman, (b) a two‐stage system consisting of a linear predictor and a second rule‐based stage, and (c) a system using wavelet coefficients of the intracranial EEG data. Results: Agreement between the two human reviewers with respect to spike identification was <50%. The automatic systems achieved agreements of 24% (Gotman), 26% (wavelet detector), and 32% (two‐stage system) with the individual human reviewers. In spite of the small proportion of agreements, the same anatomic regions were identified by human and automatic EEG analysis as generators for the majority of spikes. Conclusions: The poor agreement between the human EEG reviewers suggests that the definition of spikes and spike‐like episodes in intracranial electrodes is far from unequivocal. Nevertheless, localizing information is highly consistent by either visual or automatic spike detection, independent of the algorithm used for automatic spike detection.