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Objectives: The Automatic Stimulation Mode (AutoStim) feature of the Model 106 Vagus Nerve Stimulation (VNS) Therapy System stimulates the left vagus nerve on detecting tachycardia. This study evaluates performance, safety of the AutoStim feature during a 3-5-day Epilepsy Monitoring Unit (EMU) stay and long- term clinical outcomes of the device stimulating in all modes., Materials and Methods: The E-37 protocol (NCT01846741) was a prospective, unblinded, U.S. multisite study of the AspireSR(®) in subjects with drug-resistant partial onset seizures and history of ictal tachycardia. VNS Normal and Magnet Modes stimulation were present at all times except during the EMU stay. Outpatient visits at 3, 6, and 12 months tracked seizure frequency, severity, quality of life, and adverse events., Results: Twenty implanted subjects (ages 21-69) experienced 89 seizures in the EMU. 28/38 (73.7%) of complex partial and secondarily generalized seizures exhibited ≥20% increase in heart rate change. 31/89 (34.8%) of seizures were treated by Automatic Stimulation on detection; 19/31 (61.3%) seizures ended during the stimulation with a median time from stimulation onset to seizure end of 35 sec. Mean duty cycle at six-months increased from 11% to 16%. At 12 months, quality of life and seizure severity scores improved, and responder rate was 50%. Common adverse events were dysphonia (n = 7), convulsion (n = 6), and oropharyngeal pain (n = 3)., Conclusions: The Model 106 performed as intended in the study population, was well tolerated and associated with clinical improvement from baseline. The study design did not allow determination of which factors were responsible for improvements., (© 2015 The Authors. Neuromodulation: Technology at the Neural Interface published by Wiley Periodicals, Inc. on behalf of International Neuromodulation Society.)

Introduction: Community-based and other epidemiologic studies within the United States have identified substantial disparities in health care among adults with epilepsy. However, few data analyses addressing their health-care access are representative of the entire United States. This study aimed to examine national survey data about adults with epilepsy and to identify barriers to their health care., Materials and Methods: We analyzed data from U.S. adults in the 2010 and the 2013 National Health Interview Surveys, multistage probability samples with supplemental questions on epilepsy. We defined active epilepsy as a history of physician-diagnosed epilepsy either currently under treatment or accompanied by seizures during the preceding year. We employed SAS-callable SUDAAN software to obtain weighted estimates of population proportions and rate ratios (RRs) adjusted for sex, age, and race/ethnicity., Results: Compared to adults reporting no history of epilepsy, adults reporting active epilepsy were significantly more likely to be insured under Medicaid (RR=3.58) and less likely to have private health insurance (RR=0.58). Adults with active epilepsy were also less likely to be employed (RR=0.53) and much more likely to report being disabled (RR=6.14). They experience greater barriers to health-care access including an inability to afford medication (RR=2.40), mental health care (RR=3.23), eyeglasses (RR=2.36), or dental care (RR=1.98) and are more likely to report transportation as a barrier to health care (RR=5.28)., Conclusions: These reported substantial disparities in, and barriers to, access to health care for adults with active epilepsy are amenable to intervention., (Published by Elsevier Inc.)

Objective: Determine prevalence and incidence of epilepsy within two health insurance claims databases representing large sectors of the U.S., Methods: A retrospective observational analysis using Commercial Claims and Medicare (CC&M) Supplemental and Medicaid insurance claims data between January 1, 2007 and December 31, 2011. Over 20 million continuously enrolled lives of all ages were included. Our definition of a prevalent case of epilepsy was based on International Classification of Diseases, Ninth Revision, Clinical Modification-coded diagnoses of epilepsy or seizures and evidence of prescribed antiepileptic drugs. Incident cases were identified among prevalent cases continuously enrolled for ≥ 2 years before the year of incidence determination with no epilepsy, seizure diagnoses, or antiepileptic drug prescriptions recorded., Results: During 2010 and 2011, overall age-adjusted prevalence estimate, combining weighted estimates from all datasets, was 8.5 cases of epilepsy/1,000 population. With evaluation of CC&M and Medicaid data separately, age-adjusted prevalence estimates were 5.0 and 34.3/1,000 population, respectively, for the same period. The overall age-adjusted incidence estimate for 2011, combining weighted estimates from all datasets, was 79.1/100,000 population. Age-adjusted incidence estimates from CC&M and Medicaid data were 64.5 and 182.7/100,000 enrollees, respectively. Incidence data should be interpreted with caution due to possible misclassification of some prevalent cases., Significance: The large number of patients identified as having epilepsy is statistically robust and provides a credible estimate of the prevalence of epilepsy. Our study draws from multiple U.S. population sectors, making it reasonably representative of the U.S.-insured population., (Wiley Periodicals, Inc. © 2015 International League Against Epilepsy.)

A retrospective analysis was conducted in one claims database and was confirmed in a second independent database (covering both commercial and government insurance plans between 11/2009 and 9/2011) for the understanding of factors influencing antiepileptic drug (AED) use and the role of AEDs and other health-care factors in hospital encounters. In both datasets, epilepsy cases were identified by AED use and epilepsy diagnosis coding. Variables analyzed for effect on hospitalization rates were as follows: (1) use of first-generation AEDs or second-generation AEDs, (2) treatment changes, and (3) factors that may affect AED choice. Lower rates of epilepsy-related hospital encounters (encounters with an epilepsy diagnosis code) were associated with use of second-generation AEDs, deliberate treatment changes, and treatment by a neurologist. Epilepsy-related hospital encounters were more frequent for patients not receiving an AED and for those with greater comorbidities. On average, patients taking ≥1 first-generation AED experienced epilepsy-related hospitalizations every 684days, while those taking ≥1second-generation AED were hospitalized every 1001days (relative risk reduction of 31%, p<0.01). Prescriptions for second-generation AEDs were more common among neurologists and among physicians near an epilepsy center. Use of second-generation AEDs, access to specialty care, and deliberate efforts to change medications following epilepsy-related hospital encounters improved outcomes of epilepsy treatment based on average time between epilepsy-related hospital encounters. These factors may be enhanced by public health policies, private insurance reimbursement policies, and education of patients and physicians., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Background: Epilepsy is a common serious neurologic disorder in children. However, most studies of children's functional difficulties and school limitations have used samples from tertiary care or other clinical settings., Objective: To compare functional difficulties and school limitations of a national sample of US children with special health care needs (CSHCN) with and without epilepsy., Methods: Data from the 2009-2010 National Survey of CSHCN for 31,897 children aged 6-17 years with and without epilepsy were analyzed for CSHCN in two groups: 1) CSHCN with selected comorbid conditions (intellectual disability, cerebral palsy, autism, or traumatic brain injury) and 2) CSHCN without these conditions. Functional difficulties and school limitations, adjusted for the effect of sociodemographic characteristics, were examined by epilepsy and comorbid conditions., Results: Three percent of CSHCN had epilepsy. Among CSHCN with epilepsy 53% had comorbid conditions. Overall CSHCN with epilepsy, both with and without comorbid conditions, had more functional difficulties than CSHCN without epilepsy. For example, after adjustment for sociodemographic characteristics a higher percentage of children with epilepsy, compared to children without epilepsy, had difficulty with communication (with conditions: 53% vs. 37%, without conditions: 13% vs. 5%). Results for school limitations were similar. After adjustment, a higher percentage of children with epilepsy, compared to children without epilepsy, missed 11 + school days in the past year (with conditions: 36% vs. 18%, without conditions: 21% vs. 15%)., Conclusion: CSHCN with epilepsy, compared to CSHCN without epilepsy, were more likely to have functional difficulties and limitations in school attendance regardless of comorbid conditions., (Published by Elsevier Inc.)

Objectives: This study aimed to estimate and compare the prevalence of selected health behavior-alcohol use, cigarette smoking, physical activity, and sufficient sleep-between people with and without a history of epilepsy in a large, nationally representative sample in the United States., Methods: We used data from the 2010 cross-sectional National Health Interview Survey (NHIS) to compare the prevalence of each health behavior for people with and without epilepsy while adjusting for sex, age, race/ethnicity, and family income. We also further categorized those with epilepsy into active epilepsy and inactive epilepsy and calculated their corresponding prevalences., Results: The percentages of adults with a history of epilepsy (50.1%, 95% CI=45.1%-55.2%) and with active epilepsy (44.4%, 95% CI=37.6%-51.5%) who were current alcohol drinkers were significantly lower than that of those without epilepsy (65.1%, 95% CI=64.2%-66.0%). About 21.8% (95% CI=18.1%-25.9%) of adults with epilepsy and 19.3% (95% CI=18.7%-19.9%) of adults without epilepsy were current smokers. Adults with active epilepsy were significantly less likely than adults without epilepsy to report following recommended physical activity guidelines for Americans (35.2%, 95% CI=28.8%-42.1% vs. 46.3%, 95% CI=45.4%-47.2%) and to report walking for at least ten minutes during the seven days prior to being surveyed (39.6%, 95% CI=32.3%-47.4% vs. 50.8%, 95% CI=49.9%-51.7%). The percentage of individuals with active epilepsy (49.8%, 95% CI=42.0%-57.7%) who reported sleeping an average of 7 or 8h a day was significantly lower than that of those without epilepsy (61.9%, 95% CI=61.2%-62.7%)., Conclusions: Because adults with epilepsy are significantly less likely than adults without epilepsy to engage in recommended levels of physical activity and to get the encouraged amount of sleep for optimal health and well-being, promoting more safe physical activity and improved sleep quality is necessary among adults with epilepsy. Ending tobacco use and maintaining low levels of alcohol consumption would also better the health of adults with epilepsy., (Published by Elsevier Inc.)

Objectives: Patients with temporal lobe epilepsy (TLE) experience significant deficits in category-related object recognition and naming following standard surgical approaches. These deficits may result from a decoupling of core processing modules (e.g., language, visual processing, and semantic memory), due to "collateral damage" to temporal regions outside the hippocampus following open surgical approaches. We predicted that stereotactic laser amygdalohippocampotomy (SLAH) would minimize such deficits because it preserves white matter pathways and neocortical regions that are critical for these cognitive processes., Methods: Tests of naming and recognition of common nouns (Boston Naming Test) and famous persons were compared with nonparametric analyses using exact tests between a group of 19 patients with medically intractable mesial TLE undergoing SLAH (10 dominant, 9 nondominant), and a comparable series of TLE patients undergoing standard surgical approaches (n=39) using a prospective, nonrandomized, nonblinded, parallel-group design., Results: Performance declines were significantly greater for the patients with dominant TLE who were undergoing open resection versus SLAH for naming famous faces and common nouns (F=24.3, p<0.0001, η2=0.57, and F=11.2, p<0.001, η2=0.39, respectively), and for the patients with nondominant TLE undergoing open resection versus SLAH for recognizing famous faces (F=3.9, p<0.02, η2=0.19). When examined on an individual subject basis, no SLAH patients experienced any performance declines on these measures. In contrast, 32 of the 39 patients undergoing standard surgical approaches declined on one or more measures for both object types (p<0.001, Fisher's exact test). Twenty-one of 22 left (dominant) TLE patients declined on one or both naming tasks after open resection, while 11 of 17 right (nondominant) TLE patients declined on face recognition., Significance: Preliminary results suggest (1) naming and recognition functions can be spared in TLE patients undergoing SLAH, and (2) the hippocampus does not appear to be an essential component of neural networks underlying name retrieval or recognition of common objects or famous faces., (Wiley Periodicals, Inc. © 2014 International League Against Epilepsy.)

Background: Open surgery effectively treats mesial temporal lobe epilepsy, but carries the risk of neurocognitive deficits, which may be reduced with minimally invasive alternatives., Objective: To describe technical and clinical outcomes of stereotactic laser amygdalohippocampotomy with real-time magnetic resonance thermal imaging guidance., Methods: With patients under general anesthesia and using standard stereotactic methods, 13 adult patients with intractable mesial temporal lobe epilepsy (with and without mesial temporal sclerosis [MTS]) prospectively underwent insertion of a saline-cooled fiberoptic laser applicator in amygdalohippocampal structures from an occipital trajectory. Computer-controlled laser ablation was performed during continuous magnetic resonance thermal imaging followed by confirmatory contrast-enhanced anatomic imaging and volumetric reconstruction. Clinical outcomes were determined from seizure diaries., Results: A mean 60% volume of the amygdalohippocampal complex was ablated in 13 patients (9 with MTS) undergoing 15 procedures. Median hospitalization was 1 day. With follow-up ranging from 5 to 26 months (median, 14 months), 77% (10/13) of patients achieved meaningful seizure reduction, of whom 54% (7/13) were free of disabling seizures. Of patients with preoperative MTS, 67% (6/9) achieved seizure freedom. All recurrences were observed before 6 months. Variances in ablation volume and length did not account for individual clinical outcomes. Although no complications of laser therapy itself were observed, 1 significant complication, a visual field defect, resulted from deviated insertion of a stereotactic aligning rod, which was corrected before ablation., Conclusion: Real-time magnetic resonance-guided stereotactic laser amygdalohippocampotomy is a technically novel, safe, and effective alternative to open surgery. Further evaluation with larger cohorts over time is warranted.

This article is presented as a companion to the recent American Academy of Neurology (AAN) guideline update on use of vagus nerve stimulation (VNS) for treating epilepsy. The guideline update reaffirms the efficacy of VNS for intractable epilepsy. Whereas it upholds the value of VNS for its originally approved indications, the guideline reminds us of existing evidence gaps and unmet research needs. This companion identifies ambiguities in the definition of intractable epilepsies and discusses the use of VNS in children under age 12 years and in persons with intellectual disabilities (mental retardation). Many payers require prior authorization and fulfillment of criteria for coverage of VNS. This article provides guidance and background information to reduce obstacles for coverage, especially where uncertainties exist and levels of evidence are lower.

Epileptic encephalopathies are a devastating group of severe childhood epilepsy disorders for which the cause is often unknown. Here we report a screen for de novo mutations in patients with two classical epileptic encephalopathies: infantile spasms (n = 149) and Lennox-Gastaut syndrome (n = 115). We sequenced the exomes of 264 probands, and their parents, and confirmed 329 de novo mutations. A likelihood analysis showed a significant excess of de novo mutations in the ∼4,000 genes that are the most intolerant to functional genetic variation in the human population (P = 2.9 × 10(-3)). Among these are GABRB3, with de novo mutations in four patients, and ALG13, with the same de novo mutation in two patients; both genes show clear statistical evidence of association with epileptic encephalopathy. Given the relevant site-specific mutation rates, the probabilities of these outcomes occurring by chance are P = 4.1 × 10(-10) and P = 7.8 × 10(-12), respectively. Other genes with de novo mutations in this cohort include CACNA1A, CHD2, FLNA, GABRA1, GRIN1, GRIN2B, HNRNPU, IQSEC2, MTOR and NEDD4L. Finally, we show that the de novo mutations observed are enriched in specific gene sets including genes regulated by the fragile X protein (P < 10(-8)), as has been reported previously for autism spectrum disorders.

Little is known about the epilepsy that often occurs in the juvenile form of Huntington's disease (HD), but is absent from the adult-onset form. The primary aim of this study was to characterize the seizures in juvenile HD (JHD) subjects with regard to frequency, semiology, defining EEG characteristics, and response to antiepileptic agents. A multicenter, retrospective cohort was identified by database query and/or chart review. Data on age of HD onset, primary HD manifestations, number of CAG repeats, the presence or absence of seizures, seizure type(s), antiepileptic drugs used, subjects' response to antiepileptic drugs (AEDs), and EEG results were assembled, where available. Ninety subjects with genetically confirmed JHD were included. Seizures were present in 38% of subjects and were more likely to occur with younger ages of HD onset. Generalized tonic-clonic seizures were the most common seizure type, followed by tonic, myoclonic, and staring spells. Multiple seizure types commonly occurred within the same individual. Data on EEG findings and AED usage are presented. Seizure risk in JHD increases with younger age of HD onset. Our ability to draw firm conclusions about defining EEG characteristics and response to AEDs was limited by the retrospective nature of the study. Future prospective studies are required., (Copyright © 2012 Movement Disorder Society.)

Objectives: The most widely used and studied neurostimulation procedure for medically refractory epilepsy is vagus nerve stimulation (VNS) Therapy. The goal of this study was to develop a computational model for improved understanding of the anatomy and neurophysiology of the vagus nerve as it pertains to the principles of electrical stimulation, aiming to provide clinicians with a systematic and rational understanding of VNS Therapy., Materials and Methods: Computational modeling allows the study of electrical stimulation of peripheral nerves. We used finite element electric field models of the vagus nerve with VNS Therapy electrodes to calculate the voltage field for several output currents and studied the effects of two programmable parameters (output current and pulse width) on optimal fiber activation., Results: The mathematical models correlated well with strength-duration curves constructed from actual patient data. In addition, digital constructs of chronic versus acute implant models demonstrated that at a given pulse width and current combination, presence of a 110-μm fibrotic tissue can decrease fiber activation by 50%. Based on our findings, a range of output current settings between 0.75 and 1.75 mA with pulse width settings of 250 or 500 μs may result in optimal stimulation., Conclusions: The modeling illustrates how to achieve full or nearly full activation of the myelinated fibers of the vagus nerve through output current and pulse width settings. This knowledge will enable clinicians to apply these principles for optimal vagus nerve activation and proceed to adjust duty cycle and frequency to achieve effectiveness., (© 2012 John Wiley & Sons A/S.)

Background: VNS (Vagus Nerve Stimulation Therapy) is approved in the USA to treat refractory epilepsy as adjunctive to antiepileptic drugs (AEDs) in patients ≥12 years with complex partial seizures., Aims: To evaluate clinical outcomes, quality-adjusted life years (QALY), and costs associated with VNS in pediatric patients with drug-resistant epilepsy in a real-world setting., Methods: A retrospective analysis was conducted using Medicaid data (USA). Patients had ≥1 neurologist visits with epilepsy diagnosis (ICD-9 345.xx, 780.3x), ≥1 procedure claims for VNS implantation, ≥1 AEDs, ≥6-months of Pre- and Post-VNS continuous enrollment. Pre-VNS period was 6-months and Post-VNS period extended from implantation until device removal, death, Medicaid disenrollment, or study end (up to 3 years). Incidence rate ratios (IRR) and costs ($2010) were estimated. QALYs were estimated using number of seizure-related events., Results: For patients 1-11 years old (N = 238), hospitalizations and emergency room visits were reduced Post-VNS vs. Pre-VNS (adjusted IRR = 0.73 [95% CI: 0.61-0.88] and 0.74 [95% CI: 0.65-0.83], respectively). Average total healthcare costs were lower Post-VNS vs. Pre-VNS ($18,437 vs. $18,839 quarterly [adjusted p = 0.052]). For patients 12-17 years old (N = 207), hospitalizations and status epilepticus events were reduced Post-VNS vs. Pre-VNS (adjusted IRR = 0.43 [95% CI: 0.34-0.54] and 0.25 [95% CI: 0.16-0.39], respectively). Average total healthcare costs were lower Post-VNS vs. Pre-VNS period ($14,546 vs. $19,695 quarterly [adjusted p = 0.002]). Lifetime QALY gain after VNS was 5.96 (patients 1-11 years) and 4.82 years (patients 12-17 years)., Conclusions: VNS in pediatric patients is associated with decreased resource use and epilepsy-related events, cost savings, and QALY gain., (Copyright © 2012 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.)

We evaluated long-term medical and economic benefits of vagus nerve stimulation (VNS) therapy in drug-resistant epilepsy. A pre-post analysis was conducted using multistate Medicaid data (January 1997-June 2009). One thousand six hundred fifty-five patients with one or more neurologist visits with epilepsy diagnoses (ICD-9 345.xx, 780.3, or 780.39), one or more procedures for vagus nerve stimulator implantation, one or more antiepileptic drugs (AEDs), and 6 or more months of continuous Medicaid enrollment pre- and post-VNS were selected. The pre-VNS period was 6 months. The post-VNS period extended from implantation to device removal, death, Medicaid disenrollment, or study end (up to 3 years). Incidence rate ratios (IRRs) and cost differences ($2009) were estimated. Mean age was 29.4 years. Hospitalizations decreased post-VNS compared with pre-VNS (adjusted IRR=0.59, P<0.001). Grand mal status events decreased post-VNS compared with pre-VNS (adjusted IRR=0.79, P<0.001). Average total health care costs were lower post-VNS than pre-VNS ($18,550 vs $19,945 quarterly, P<0.001). VNS is associated with decreased resource utilization and epilepsy-related clinical events and net cost savings after 1.5 years., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Background: Cerebral palsy is a heterogeneous group of neurodevelopmental brain disorders resulting in motor and posture impairments often associated with cognitive, sensorial, and behavioural disturbances. Hypoxic-ischaemic injury, long considered the most frequent causative factor, accounts for fewer than 10% of cases, whereas a growing body of evidence suggests that diverse genetic abnormalities likely play a major role., Methods and Results: This report describes an autosomal recessive form of spastic tetraplegic cerebral palsy with profound intellectual disability, microcephaly, epilepsy and white matter loss in a consanguineous family resulting from a homozygous deletion involving AP4E1, one of the four subunits of the adaptor protein complex-4 (AP-4), identified by chromosomal microarray analysis., Conclusion: These findings, along with previous reports of human and mouse mutations in other members of the complex, indicate that disruption of any one of the four subunits of AP-4 causes dysfunction of the entire complex, leading to a distinct 'AP-4 deficiency syndrome'.

This study quantifies the economic burden associated with generic-versus-branded use of antiepileptic drugs (AEDs) in the United States. Adult patients with epilepsy receiving carbamazepine, gabapentin, phenytoin, primidone, or zonisamide were selected from the PharMetrics database. By use of an open-cohort design, patients were classified into mutually exclusive periods of generic-versus-branded AED use. Annualized cost differences (CDs) between periods were estimated using multivariate regressions. Results were stratified into stable versus unstable epilepsy and newer-generation versus older-generation AEDs. A total of 33,625 patients (52% male, mean age=51 years) were observed. Periods of generic AED treatment were associated with higher medical service costs (adjusted CD [95% CI]=$3186 [$2359; $4012]), stable pharmacy costs ($69 [$-34; $171]), and greater total costs ($3254 [$2403; $4105]) versus brand use. Epilepsy-related costs represented 30% of incremental costs. Similar findings were observed for patients with stable and unstable epilepsy and users of newer-generation and older-generation AEDs. Significantly higher health care costs were observed during generic AED use across seizure control and AED subgroups., (Copyright 2010 Elsevier Inc. All rights reserved.)

More than 10 years ago, the vagus nerve stimulator became the first device approved by the Food and Drug Administration for use in persons with epilepsy. The vagus nerve stimulator has subsequently served to spearhead the concept of neurostimulation for seizures. Chronic intermittent electrical stimulation of the left vagus nerve is the foundation for vagus nerve stimulation, yet little is known about its capability to deliver acute, on-demand, activation of stimulation through use of a magnet. Thus far, clinical use of magnet-induced vagus nerve stimulation has not been elucidated. In an effort to help guide management, we highlight current and potential uses of acute abortive therapy with vagus nerve stimulation. We review the current evidence that is available for vagus nerve stimulator magnet use, discuss potential clinical applications that exist, offer a protocol for magnet application within the institutional setting, provide our approach to titrating the magnet parameters, and make recommendations for magnet use that support an evolving standard of care.

Epilepsy is a common disorder in childhood. The effects of recurrent seizures and the use of antiepileptic drugs (AEDs) during childhood and adolescence on reproductive endocrine health are poorly defined. We review effects of hormones on epilepsy and vice versa along with the effects of treatment (AEDs) on hormones in children.

Mutations in three voltage-gated sodium channel genes, SCN1A, SCN2A, and SCN1B, and two GABAA receptor subunit genes, GABRG2 and GABRD, have been identified in families with generalized epilepsy with febrile seizures plus (GEFS+). A novel mutation, R859C, in the Nav1.1 sodium channel was identified in a four-generation, 33-member Caucasian family with a clinical presentation consistent with GEFS+. The mutation neutralizes a positively charged arginine in the domain 2 S4 voltage sensor of the Nav1.1 channel alpha subunit. This residue is conserved in mammalian sodium channels as well as in sodium channels from lower organisms. When the mutation was placed in the rat Nav1.1 channel and expressed in Xenopus oocytes, the mutant channel displayed a positive shift in the voltage dependence of sodium channel activation, slower recovery from slow inactivation, and lower levels of current compared with the wild-type channel. Computational analysis suggests that neurons expressing the mutant channel have higher thresholds for firing a single action potential and for firing multiple action potentials, along with decreased repetitive firing. Therefore, this mutation should lead to decreased neuronal excitability, in contrast to most previous GEFS+ sodium channel mutations, which have changes predicted to increase neuronal firing.

Context: The past decade has brought many advances to the treatment of epilepsy, including many new pharmacological agents. Primary care physicians often care for patients with epilepsy and therefore should be familiar with the new options available., Objective: To review data regarding the efficacy and tolerability of antiepileptic drugs introduced in the past decade., Data Sources: A search of the Cochrane Central Register of Controlled Trials was performed to identify all published human and English-language randomized controlled trials evaluating the efficacy and tolerability of the antiepileptic drugs that have been approved for use in the United States since 1990. Additional reports evaluating pharmacokinetic properties were identified through a MEDLINE search as well as review of article bibliographies., Study Selection and Data Extraction: Search terms included felbamate, gabapentin, lamotrigine, topiramate, tiagabine, levetiracetam, oxcarbazepine, and zonisamide. Studies were selected if efficacy and tolerability were reported as major outcome measures. Included studies (n = 55) enrolled a minimum of 20 adult subjects and had a treatment period of at least 6 weeks., Data Synthesis: Eight new antiepileptic drugs have been approved for use in the United States in the past decade. Each new antiepileptic drug is well tolerated and demonstrates statistically significant reductions in seizure frequency over baseline. No randomized controlled trials have compared the new antiepileptic drugs with each other or against the traditional antiepileptic drugs. Although there is no evidence to suggest that the newer medications are more efficacious, several studies have demonstrated broader spectrum of activity, fewer drug interactions, and overall better tolerability of the new agents., Conclusions: New antiepileptic drugs offer many options in the treatment of epilepsy, each with unique mechanisms of action as well as adverse effect profiles. The new antiepileptic drugs are well tolerated with few adverse effects, minimal drug interactions, and a broad spectrum of activity.

In the past decade, 8 new antiepileptic drugs have been approved for use in the United States, offering many new treatment options to patients with epilepsy. With expanding use of these newer agents, primary care clinicians are challenged with understanding the roles that each new agent plays in the treatment of patients with epilepsy as well as possible interactions with other pharmacological therapies. Each new medication provides a unique profile of pharmacokinetics, adverse effects, and mechanisms of action, making an appreciation of how these agents are best utilized even more difficult. Despite well-performed trials evaluating the safety and efficacy of specific antiepileptic drugs, the lack of head-to-head comparisons among them makes it difficult to endorse a single therapeutic regimen. Limited studies have compared the new antiepileptic drugs with more traditional medications and found similar efficacy but improved tolerability of the newer agents. There remains no well-established guidelines for choosing a particular antiepileptic drug or for choosing a newer agent over a traditional one. However, careful consideration of seizure type, patient comorbidities, and specific medication toxicities aids in prescribing the most appropriate medication. This article aims to familiarize the general practitioner with the appropriate roles and effective uses of the new antiepileptic drugs in specific clinical scenarios.

This study was performed to clarify alterations in lamotrigine (LTG) clearance during pregnancy and childbirth. Fourteen women on LTG monotherapy had LTG concentration samples obtained before conception and monthly. LTG apparent clearance, weight-adjusted relative clearance, and percentages of baseline clearance significantly differed between preconception baseline and each trimester and between trimesters. LTG clearance progressively increased until 32 weeks' gestational age, reaching a peak of >330% of baseline, and then began to decline.

Background: Epilepsy is one of the most common neurologic diseases that affect the elderly population. Underlying etiologies as well as diagnostic and treatment issues vary from that of younger adults and deserve special consideration., Review Summary: The substantially increased risk of seizures and epilepsy in the elderly is associated with medical conditions that affect this group such as stroke, dementia, and metabolic disturbances. In addition, there is an increased incidence and associated mortality of status epilepticus among seniors. Distinguishing epilepsy from paroxysmal nonepileptic events can be a particular challenge. As in the general adult population, EEG and MRI are the cornerstones of diagnostic assessment; however, the clinician must be aware of nonspecific changes associated with aging that do not necessarily indicate an underlying predisposition for epilepsy. Finally, there are unique challenges to the treatment of epilepsy in this population, but fortunately there are multiple treatment options available, including nonpharmacological therapies., Conclusions: Knowledge of the unique challenges in identifying and treating the elderly patient with epilepsy is important for effective management as well as maximizing quality of life. However, further studies in this area are still needed to establish optimal treatment strategies.

Background: This study retrospectively compared the effectiveness of vagus nerve stimulation (VNS) therapy among a constant cohort of patients in the patient outcome registry, which systematically monitors outcomes of patients receiving VNS therapy. Patients in the study had pharmacoresistant seizures for 6 years or less (early treatment group) or more than 6 years (late treatment group) before initiation of VNS therapy, and results are provided after both 3 and 12 months., Review Summary: Of 405 patients, 51 were in the early and 354 in the late treatment groups. Median age at onset of seizures was 7 years in the early and 4.5 years in the late treatment group. Seizure reduction of 100% was reported in 7.8% (early) and 3.7% (late) patients at 3 months and 11.8% (early) and 4.5% (late) at 12 months (P = 0.033). Reductions in seizure frequency greater than or equal to 90% for early and late treatment groups were similar: 11.8% (early) and 11.0% (late) at 3 months and 23.5% (early) and 17.0% (late) at 12 months., Conclusions: Patients treated earlier with VNS therapy were twice as likely to report no seizures as patients who had seizures for more than 6 years before they received VNS therapy. The effectiveness of VNS therapy should be assessed among other patients with pharmacoresistant seizures and lesser cumulative seizure loads.

This six-center, retrospective study evaluated the effectiveness, tolerability, and safety of vagus nerve stimulation in children. Data were available for 125 patients at baseline, 95 patients at 3 months, 56 patients at 6 months, and 12 patients at 12 months. The typical patient, aged 12 years, had onset of seizures at age 2 years and had tried nine anticonvulsants before implantation. Collected data included preimplant history, seizures, implant, device settings, quality of life, and adverse events. Average seizure reduction was 36.1% at 3 months and 44.7% at 6 months. Common adverse events included voice alteration and coughing during stimulation. Rare adverse events, unique to this age group, included increased drooling and increased hyperactivity. Quality of life improved in alertness, verbal communication, school performance, clustering of seizures, and postictal periods. We concluded that vagus nerve stimulation is an effective treatment for medically refractory epilepsy in children.

Therapeutic options for intractable epilepsy include new and investigational antiepileptic drugs, ketogenic diet, epilepsy surgery, and, now, vagus nerve stimulation, which is approved by the U.S. Food and Drug Administration for the treatment of refractory partial seizures in adolescents and adults. The exact mechanisms of action are unknown. Although the use of vagus nerve stimulation in children has increased, including those younger than 12 years of age or those with generalized epilepsy, there has been no large controlled pediatric study to date. The identification of favorable prognostic indicators, especially in children, would be useful. Preliminary results suggest that children with Lennox-Gastaut syndrome may have a favorable response, with improvement in both seizure control and global evaluation scores. Improved global evaluation scores have occurred even without an associated improvement in seizure control.

Purpose: Vagus nerve stimulation (VNS) is approved for use for refractory partial seizures. Nevertheless, information regarding VNS therapy for special populations, including Lennox-Gastaut syndrome (LGS) is limited. We discuss the effectiveness, tolerability, and safety of VNS therapy in patients with LGS., Methods: A six-center, retrospective study evaluated the effectiveness of VNS therapy in patients with LGS at 3 and 6 months and compared preimplant and postimplant seizure frequency. Adverse effects and quality of life (QOL) were included as secondary measures., Results: Fifty patients, median age 13 years, with medically refractory epilepsy, were implanted. Median age at onset of seizures was 1.4 years, and a median of nine anticonvulsants (AEDs) had been tried before implantation. Data-collection forms were designed for retrospectively gathering data on each patient's preimplant history, seizures, implants, device settings, QOL, and adverse events. Median reductions in total seizures were 42% at 1 month, 58.2% at 3 months, and 57.9% at 6 months. The most common adverse events reported were voice alteration and coughing during stimulation. Other uncommon adverse events included increased drooling and behavioral changes. Investigators noted that QOL had improved for some patients in the study., Conclusions: VNS is an effective treatment for medically refractory epilepsy in LGS. This treatment is well tolerated, safe, and may improve QOL.

Purpose: Topiramate (TPM) has been widely used as an adjunctive therapy for treating epilepsy. TPM is reported to have multiple mechanisms of action, including inhibition of carbonic anhydrase, which may result in metabolic acidosis from decreased serum bicarbonate (HCO3-)., Methods: Clinical data from 30 children who received TPM as adjunctive therapy for medically refractory epilepsy were reviewed at Children's Hospital, Boston. Serum HCO3- levels were assessed before, during, and after discontinuing TPM (n = 9). When multiple data were available, mean values were used for analysis., Results: Of the 30 patients, 21 had a >10% decrease in HCO3- levels. The mean decrease in HCO3- among the 21 patients was 4.7 mEq/L, and maximum was 10 mEq/L. No clinical symptoms occurred, and HCO3- supplement was not needed, except for one patient who developed tachypnea from worsened acidosis after prolonged status epilepticus during a suspected viral illness. Among the 21 patients, TPM was discontinued in seven children because of a lack of efficacy, and in two because of anorexia. After discontinuing TPM, the serum HCO3- returned to the previous level before starting TPM in all nine., Conclusions: Decreased HCO3- levels occurred in the majority of patients reviewed, usually only to a small to moderate extent, but by 8 and 10 mEq/L in two cases. In patients at risk for acidosis, the decrease in HCO3- may cause significant consequences, such as severe acidosis or renal calculi. Monitoring HCO3- levels before and during TPM therapy may be indicated, especially with conditions that predispose to acidosis.

Magnetic resonance imaging (MRI) changes reported after corpus callosotomy include hyperintensity in the corpus callosum, perifalcine hyperintensity caused by surgical retraction, and acute changes associated with surgical complications. The authors have observed MRI signal changes in the cerebral white matter of corpus callosotomy patients that are separate from the sectioned callosum and not clearly related to surgical manipulation or injury. Brain MRI scans were retrospectively reviewed in 25 of 38 patients who underwent anterior, posterior, or total callosotomy for refractory seizures between 1988 and 1995. Nine patients had signal changes in the cerebral white matter on postoperative MRI. Six of these patients had preoperative MRI studies available for comparison, and none of the white matter signal abnormalities were evident preoperatively. T2 prolongation or hyperintensity on proton-density images was observed in areas including the centrum semiovale, forceps major, and forceps minor. Three patients had signal changes that had distinct borders extending only to the posterior limit of the callosotomy. MRI signal changes in the cerebral white matter after corpus callosotomy have not been previously reported and may represent distant effects of callosal section. Wallerian degeneration occurring in the neuronal processes cut during surgery could account for the signal changes.

Objective: To investigate the long-term effects of two widely used antiepileptic medications, valproate and phenobarbital, on learning and behavior in the kainic acid (KA) model of epilepsy., Background: Prior clinical and animal studies have demonstrated that phenobarbital administered during development may result in subsequent cognitive impairment. It is unclear whether these adverse effects of phenobarbital extend to other antiepileptic drugs., Methods: A convulsant dose of KA was administered to rats on postnatal day (P) 35. From P36-75 rats received daily injections of phenobarbital (PH), valproate (VPA), or saline and spontaneous seizure frequency was monitored with video recordings. After tapering of the drugs, the rats were tested in the water maze (a measure of visuospatial memory) and handling test (a measure of emotionality). Brains were then analyzed for histologic lesions., Results: KA caused status epilepticus in all the rats. In the PH- and saline-treated groups, there was impaired learning in the water maze, increased emotionality, recurrent seizures, and histologic lesions in the hippocampal areas CA3, CA1, and dentate hilus. However, VPA-treated rats had no spontaneous seizures, abnormalities in handling, or deficits in visuospatial learning, and had fewer histologic lesions than animals receiving KA alone., Conclusions: The long-term consequences of AED treatment during development are related to the drug used. VPA treatment after KA-induced status epilepticus prevents many of the neurologic sequelae typically seen after KA.

Background: The outcome of infants who have transient seizures after open heart surgery has not been studied. Using the database of the Boston Circulatory Arrest Study involving 171 children with D-transposition of the great arteries, we explored the relationship between early postoperative clinical and EEG seizures and neurodevelopmental outcomes at ages 1 and 2 1/2 years., Methods and Results: At 1 year, children returned for developmental and neurological evaluations and MRI. Parent-completed developmental questionnaires were collected at 2 1/2 years of age. At 1 year, children with early postoperative seizures had lower Psychomotor Development Index (motor function) scores (clinical seizures: 12.9 mean difference [MD]; 95% confidence interval [CI], 2.2 to 23.6; P=.02; EEG seizures: 13.3 MD; 95% CI, 6.8 to 19.7; P<.001). Mental Developmental Index scores of children with clinical or EEG seizures were also lower, but the differences were not statistically significant. Infants with seizures were more likely to have an abnormal neurological examination (clinical seizures: 78% versus 31%; P=.008; EEG seizures: 58% versus 34%; P=.04). Children with EEG seizures were more likely to have MRI abnormalities (43% versus 13%, P=.002). At age 2 1/2, children with EEG seizures had lower scores in several areas of function., Conclusions: In infants undergoing the arterial switch operation for correction of D-transposition of the great arteries, transient postoperative clinical and EEG seizures were associated with worse neurodevelopmental outcomes at ages 1 and 2 1/2 years as well as neurological and MRI abnormalities at 1 year of age. The occurrence of such seizures may provide an early sign of brain injury with neurological and developmental sequelae.

Seizure disorders can produce anxiety that is almost indistinguishable from psychiatric disorders. There are few reports of adolescents with seizure disorders that produce fear. The first case of an adolescent female who presented with panic disorder and agoraphobia which was a consequence of seizure activity is reported. Careful diagnostic evaluation and correlation with video electroencephalography were important in distinguishing seizure activity from panic disorder.

Many infants with cardiac anomalies undergo repair early in life. Both commonly used support techniques, deep hypothermic circulatory arrest (DHCA) and low-flow cardiopulmonary bypass (LFB), may be associated with adverse neurological outcomes, including seizures. In a single center study, 171 infants undergoing correction for D-transposition of the great arteries were randomized to one of these support techniques. Incidence and onset times of EEG seizures during continuous EEG-video monitoring in the first 48 h postoperatively and clinical seizures in the first postoperative week were compared. EEG seizures were characterized by time, duration, and localization of onset. Incidence of EEG seizures (20%) was more than 3 times that of clinical seizures (6%). Most infants with EEG seizures had multiple seizures beginning between 13 and 36 h postoperatively. Durations ranged from 6 s to 980 min. Onset of EEG seizures occurred most commonly in frontal and central regions. Factors associated with EEG seizures included randomization to DHCA, longer duration of circulatory arrest, and diagnosis of VSD. In this study EEG seizures were common following this type of cardiac surgery, illustrating the importance of EEG monitoring in detecting seizures. This data adds insight into mechanisms of seizures in infants undergoing cardiac surgery.

Purpose: Because oral, buccal, and sometimes oral-pharyngeal manifestations in epilepsy are linked to the central-temporal region, we studied 3 patients with childhood-onset partial seizures that consistently began with pharyngeal dysesthesias, described as either throat tingling or burning, to localize seizure onset., Methods: Because of an intractable clinical course, each patient underwent invasive video-EEG monitoring, which localized the epileptogenic zone to the mesial temporal lobe. The 3 patients underwent temporal lobe resections., Results: All 3 patients achieved remission of the pharyngeal auras and a 90-100% reduction in the frequency of their seizures., Conclusions: Pharyngeal dysesthesias can be the initial manifestation of complex partial seizures (CPS) of temporal lobe origin.

Staring is frequently a nonepileptic manifestation in children. To differentiate epileptic versus nonepileptic staring, we reviewed clinical and video-EEG findings in 143 patients, aged 5 months to 43 years, monitored for staring episodes. In 79 patients staring was of epileptic origin; 46 had partial seizures and 33 atypical absence. Thirty-five had behavioral staring, 8 psychogenic seizures, 1 a migraine equivalent, and in 20 no staring spells were recorded. In all patients with epileptic staring, epilepsy was suspected clinically. Only 22 of the admissions for behavioral staring and 3 for pseudoseizures were to exclude a possible nonepileptic phenomenon. Review of their clinical histories revealed that certain findings strongly support a nonepileptic origin. In conclusion, a careful clinical history will differentiate between epileptic and nonepileptic staring episodes in most patients. Video-monitoring is helpful to adjust treatment or to exclude nonepileptic events in patients with refractory staring spells.

We report 7 children who received gabapentin (GBP) as adjunctive medic ation and subsequently developed behavioral side effects. These behavioral changes consisted of intensification of baseline behaviors as well as new behavioral problems. Behaviors that parents considered most troublesome were tantrums, aggression directed toward others, hyperactivity, and defiance. All behavioral changes were reversible and were managed by dose reduction or discontinuation of GBP. All children had baseline attention deficit hyperactivity disorder and developmental delays.