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Objective: The objective was to systematically evaluate the current evidence surrounding the effect of vagus nerve stimulation (VNS) on quality of sleep and obstructive sleep apnea (OSA) among patients with epilepsy., Methods: A literature search was conducted using the Embase and MEDLINE databases. Studies were included if they involved patients with drug-resistant epilepsy treated with VNS and used validated tools to report on quality of sleep or sleep apnea. The literature search yielded 112 citations related to VNS and sleep quality, and 82 citations related to sleep apnea. Twelve articles were included in the review, of which five measured quality of sleep among patients who underwent VNS, six studies measured sleep apnea, and one study measured both outcomes., Results: Studies measuring quality of sleep used different methods, including sleep quality questionnaires and the percentage of sleep in each cycle. Studies also varied in patient populations, the use of control groups, and whether multiple measurements were taken for each patient. Some studies found improved sleep quality after VNS, whereas others found reductions in deep sleep stages. Additionally, mixed results in sleep quality were found when comparing patients with epilepsy who received VNS treatment versus patients with epilepsy who did not receive VNS treatment. Variables such as VNS intensity and age could potentially confound quality of sleep. Studies measuring sleep apnea consistently found increased proportions of patients diagnosed with OSA or increased sleep index scores after VNS implantation., Significance: Overall, the effect of VNS on quality of sleep remains unclear, as studies were very heterogeneous, although the effect on sleep apnea has consistently shown an increase in sleep apnea severity indices after VNS implantation. Future studies with consistent measures and discussions of confounding are required to determine the effect of VNS on quality of sleep, and the effect of VNS parameters should be further explored among patients who develop sleep apnea., (© 2023 The Authors. Epilepsia published by Wiley Periodicals LLC on behalf of International League Against Epilepsy.)

Objective: There are three neurostimulation devices available to treat generalized epilepsy: vagus nerve stimulation (VNS), deep brain stimulation (DBS), and responsive neurostimulation (RNS). However, the choice between them is unclear due to lack of head-to-head comparisons. A systematic comparison of neurostimulation outcomes in generalized epilepsy has not been performed previously. The goal of this meta-analysis was to determine whether one of these devices is better than the others to treat generalized epilepsy., Methods: Following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, a systematic review of PubMed, Embase, and Web of Science was performed for studies reporting seizure outcomes following VNS, RNS, and DBS implantation in generalized drug-resistant epilepsy between the first pivotal trial study for each modality through August 2022. Specific search criteria were used for VNS ("vagus", "vagal", or "VNS" in the title and "epilepsy" or "seizure"), DBS ("deep brain stimulation", "DBS", "anterior thalamic nucleus", "centromedian nucleus", or "thalamic stimulation" in the title and "epilepsy" or "seizure"), and RNS ("responsive neurostimulation" or "RNS" in the title and "epilepsy" or "seizure"). From 4409 articles identified, 319 underwent full-text reviews, and 20 studies were included. Data were pooled using a random-effects model using the meta package in R., Results: Sufficient data for meta-analysis were available from seven studies for VNS (n = 510) and nine studies for DBS (n = 87). Data from RNS (five studies, n = 18) were insufficient for meta-analysis. The mean (SD) follow-up durations were as follows: VNS, 39.1 (23.4) months; DBS, 23.1 (19.6) months; and RNS, 22.3 (10.6) months. Meta-analysis showed seizure reductions of 48.3% (95% confidence interval [CI] = 38.7%-57.9%) for VNS and 64.8% (95% CI = 54.4%-75.2%) for DBS (p = .02)., Significance: Our meta-analysis indicates that the use of DBS may lead to greater seizure reduction than VNS in generalized epilepsy. Results from RNS use are promising, but further research is required., (© 2023 International League Against Epilepsy.)

Neuromodulation is a key therapeutic tool for clinicians managing patients with drug-resistant epilepsy. Multiple devices are available with long-term follow-up and real-world experience. The aim of this review is to give a practical summary of available neuromodulation techniques to guide the selection of modalities, focusing on patient selection for devices, common approaches and techniques for initiation of programming, and outpatient management issues. Vagus nerve stimulation (VNS), deep brain stimulation of the anterior nucleus of the thalamus (DBS-ANT), and responsive neurostimulation (RNS) are all supported by randomized controlled trials that show safety and a significant impact on seizure reduction, as well as a suggestion of reduction in the risk of sudden unexplained death in epilepsy (SUDEP). Significant seizure reductions are observed after 3 months for DBS, RNS, and VNS in randomized controlled trials, and efficacy appears to improve with time out to 7 to 10 years of follow-up for all modalities, albeit in uncontrolled follow-up or retrospective studies. A significant number of patients experience seizure-free intervals of 6 months or more with all three modalities. Number and location of epileptogenic foci are important factors affecting efficacy, and together with comorbidities such as severe mood or sleep disorders, may influence the choice of modality. Programming has evolved-DBS is typically initiated at lower current/voltage than used in the pivotal trial, whereas target charge density is lower with RNS, however generalizable optimal parameters are yet to be defined. Noninvasive brain stimulation is an emerging stimulation modality, although it is currently not used widely. In summary, clinical practice has evolved from those established in pivotal trials. Guidance is now available for clinicians who wish to expand their approach, and choice of neuromodulation technique may be tailored to individual patients based on their epilepsy characteristics, risk tolerance, and preferences., (© 2022 International League Against Epilepsy.)

Although vagus nerve stimulation (VNS) is a common procedure, seizure outcomes are heterogeneous, with few available means to preoperatively identify the ideal surgical candidate. Here, we perform a scoping review of the literature to identify biomarkers of VNS response in patients with drug-resistant epilepsy. Several databases (Ovid MEDLINE, Ovid Embase, BIOSIS Previews, and Web of Science) were searched for all relevant articles that reported at least one biomarker of VNS response following implantation for intractable epilepsy. Patient demographics, seizure data, and details related to biomarkers were abstracted from all studies. From the 288 records screened, 28 articles reporting on 16 putative biomarkers were identified. These were grouped into four categories: network/connectomic-based biomarkers, electrophysiological signatures, structural findings on neuroimaging, and systemic assays. Differences in brain network organization, connectivity, and electrophysiological synchronicity demonstrated the most robust ability to identify VNS responders. Structural findings on neuroimaging yielded inconsistent associations with VNS responsiveness. With regard to systemic biomarkers, heart rate variability was shown to be an independent marker of VNS response, whereas inflammatory markers were not useful. There is an unmet need to preoperatively identify candidates who are likely to benefit from VNS. Several biomarkers demonstrate promise in predicting seizure responsiveness to VNS, particularly measures of brain network connectivity. Further efforts are required to validate existing biomarkers to inform clinical decision-making., (© 2020 International League Against Epilepsy.)

Prompted by a recent report on declining incidence of sudden unexpected death in epilepsy (SUDEP) following implantation of a vagus nerve stimulator (VNS), we analyzed SUDEP risk over 6 years in a population-based cohort of 60 952 epilepsy patients in Sweden. All deaths from July 1, 2006 through December 31, 2011, were identified. Those with epilepsy mentioned on the death certificate were adjudicated for SUDEP using medical records and autopsy reports. In all, 292 SUDEP cases were identified. Comparing the first years (2006-2007) with the subsequent 4 years (2008-2011), the crude and standardized (to the US 2000 population) incidence of SUDEP (whether or not possible SUDEP was included) was significantly lower during the second time period; Incidence rate ratios based on standardized rates was estimated at 0.76 (95% confidence interval [CI] 0.60-0.97, P = .027) for SUDEP. The incidence of SUDEP decreased by 7% per year during the 6-year follow-up. Our data thus suggest that, for unknown reasons, incidence of SUDEP decreases with duration of follow-up. This has implications for patient counseling as well as for the design of studies attempting to assess the effectiveness of an intervention against SUDEP, which clearly needs to include a control group., (Wiley Periodicals, Inc. © 2018 International League Against Epilepsy.)

Indications for vagus nerve stimulation (VNS) therapy include focal, multifocal epilepsy, drop attacks (tonic/atonic seizures), Lennox-Gastaut syndrome, tuberous sclerosis complex (TSC)-related multifocal epilepsy, and unsuccessful resective surgery. Surgical outcome is about 50-60% for seizures control, and may also improve mood, cognition, and memory. On this basis, VNS has also been proposed for the treatment of major depression and Alzheimer's' disease. The vagus nerve stimulator must be implanted with blunt technique on the left side to avoid cardiac side effects through the classic approach for anterior cervical discectomy. The actual device is composed of a wire with three helical contacts (two active contacts, one anchoring) and a one-pin battery. VNS is usually started 2 weeks after implantation with recommended settings of stimulation (1.0-2.0 mA; 500 μs pulse width; 20-30 Hz; 30 s ON, 5 min OFF). The complications of VNS therapy are early (related to surgery) and late (related to the device and to stimulation of the vagus nerve). Early complications include the following: intraoperative bradycardia and asystole during lead impedance testing, peritracheal hematoma, infections (3-8%), and vagus nerve injury followed by hoarseness, dyspnea, and dysphagia because of left vocal cord paralysis. Delayed morbidity due to the device includes late infections or problems in wound healing; other more rare events are due to late injury of the nerve. Late complications due to nerve stimulation include delayed arrhythmias, laryngopharyngeal dysfunction (hoarseness, dyspnea, and coughing), obstructive sleep apnea, stimulation of phrenic nerve, tonsillar pain mimicking glossopharyngeal neuralgia, and vocal cord damage during prolonged endotracheal intubation. The laryngopharyngeal dysfunction occurs in about 66% of patients and is usually transitory and due to the stimulation of the inferior (recurrent) laryngeal nerve. A true late paralysis of the left vocal cord is often partial and rare (1-2.7%), and usually transitory, and may be caused by previous surgical trauma (i.e., damage of nerve fibers and/or of their blood supply) or to a supposed chronic denervation during stimulation. Surgery for complete removal or revision and replacement of the device is to be considered in cases of device malfunction (4-16.8%), failure of VNS therapy, intolerable side effects, or because of patient's specific request. As described in the literature, the surgical techniques of lead revision and replacement are two: sharp and blunt dissection of helical electrodes and replacement; and blunt dissection combined with ultrasharp low-voltage cautery dissection. The incidence of left vocal cord palsy after vagus nerve stimulator replacement/revision is slightly higher than that of first implantation (4.9% vs. 3.8%). A de novo implantation in a naive segment of the left or right vagus nerve may be considered in specific cases; the use of the right vagus nerve is a rare exception that may be chosen with an acceptable result., (Wiley Periodicals, Inc. © 2017 International League Against Epilepsy.)

Objective: Following a sudden death at a residential care unit, the Dutch Health and Care Inspectorate advised intensification of the use of video monitoring (VM) at the unit. We assessed whether VM resulted in increased identification of seizures that required clinical intervention., Methods: The unit provides care for 340 individuals with refractory epilepsy and severe learning disabilities. Acoustic detection systems (ADSs) cover all individuals; 37 people also have a bed motion sensor (BMS) and 46 people with possible nocturnal seizures are now monitored by VM. During a 6-month period, in all cases of a suspected seizure we asked the caregivers to specify which device alerted them and to indicate whether this led to an intervention. Staff costs of VM were estimated using payroll information., Results: We identified 1,208 seizures in 37 individuals: 4 had no nocturnal seizures and 393 (33%) seizures were seen only on video. In 169 (14%) of 1,208 seizures an intervention was made and this included 39 (10%) of 393 seizures seen only on video. When compared to seizures observed with an ADS or BMS, seizures seen only on video were more often tonic seizures (71% vs. 22%, p < 0.001) and occurred mostly in the beginning or at the end of the night (40% vs. 26%, p < 0.001). The extra staff costs of monitoring was 7,035 euro per seizure seen only on video and leading to an intervention., Significance: VM facilitates nocturnal surveillance, but the costs are high. This underscores the need for development of reliable seizure detection devices., (Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.)

Objective: The cardiac component of risk for sudden unexpected death in epilepsy (SUDEP) and alterations in cardiac risk by vagus nerve stimulation (VNS) are not well understood. We determined changes in T-wave alternans (TWA), a proven noninvasive marker of risk for sudden cardiac death in patients with cardiovascular disease, and heart rate variability (HRV), an indicator of autonomic function, in association with VNS in patients with drug-resistant focal epilepsy., Methods: Ambulatory 24-h electrocardiograms (N = 9: ages 29-63, six males) were analyzed., Results: Mean TWA during the interictal period was 37 ± 3.1 μV (mean ± SEM) in lead V1 for nine patients monitored following implantation of the VNS system (n = 7) or battery change (n = 2). Of these, six patients also monitored prior to implantation (n = 5) or battery change (n = 1) showed abnormally high TWA levels pre-VNS (60.0 ± 4.3 μV), which were significantly reduced by 24.3 μV (to 35.7 ± 4.8 μV, p = 0.02) after VNS settings were adjusted for desired clinical response. TWA in four (67%) of the six patients was reduced in association with VNS to levels below the 47-μV cut point of abnormality. The decrease in TWA was correlated with VNS intensity (r = 0.88, p < 0.02). In addition, low-frequency HRV was reduced by 60% (805.61 ± 253.96 to 323.49 ± 102.74 msec(2) , p = 0.05) and low-to high-frequency HRV ratio by 32% (3.34 ± 0.57 to 2.26 ± 0.31, p = 0.025), indicating a change in autonomic balance in favor of parasympathetic dominance., Significance: This is the first report that elevated levels of TWA in patients with drug-refractory partial-onset seizures were reduced in association with VNS, potentially by improving sympathetic/parasympathetic balance. VNS may have a cardioprotective role at stimulation settings typically used for seizure control. These findings indicate the utility of TWA for tracking improvement in cardiac status in this population., (Wiley Periodicals, Inc. © 2014 International League Against Epilepsy.)

Although implanted metallic devices constitute a relative contraindication to magnetic resonance imaging (MRI) scanning, the safety of brain imaging in a patient with a vagus nerve stimulator (VNS) is classified as "conditional," provided that specific manufacturer guidelines are followed when a transmit and receive head coil is used at 1.5 or 3.0 Tesla. The aim of this study was to evaluate the safety of performing brain MRI scans in patients with the VNS. From September 2009 until November 2011, 101 scans were requested in 73 patients with the VNS in The Netherlands. Patients were scanned according to the manufacturer's guidelines. No patient reported any side effect, discomfort, or pain during or after the MRI scan. In one patient, a lead break was detected based on device diagnostics after the MRI-scan. However, because no system diagnostics had been performed prior to MR scanning in this patient, it is unclear whether MR scanning was responsible for the lead break. The indication for most scans was epilepsy related. Twenty-six scans (26%) were part of a (new) presurgical evaluation and could probably better have been performed prior to VNS implantation. Performing brain MRI scans in patients with an implanted VNS is safe when a modified MRI protocol is followed., (Wiley Periodicals, Inc. © 2014 International League Against Epilepsy.)

Objective: To gain insight into the long-term impact of vagus nerve stimulation (with VNS Therapy) in children with drug-resistant epilepsy, we conducted the largest retrospective multicenter study to date over an extended follow-up period of up to 24 months., Methods: The primary objective was to assess change in seizure frequency of the predominant seizure type (defined as the most disabling seizure) following VNS device implantation. Treating physicians collected data from patient records from baseline to 6, 12, and 24 months of follow-up., Results: The analysis population included 347 children (aged 6 months to 17.9 years at the time of implant). At 6, 12, and 24 months after implantation, 32.5%, 37.6%, and 43.8%, respectively, of patients had ≥ 50% reduction in baseline seizure frequency of the predominant seizure type. The responder rate was higher in a subgroup of patients who had no change in antiepileptic drugs (AEDs) during the study. Favorable results were also evident for all secondary outcome measures including changes in seizure duration, ictal severity, postictal severity, quality of life, clinical global impression of improvement, and safety. Post hoc analyses demonstrated a statistically significant correlation between VNS total charge delivered per day and an increase in response rate. VNS Therapy is indicated as adjunctive therapy in children with focal, structural epilepsies, who for any reason are not good candidates for surgical treatment following the trial of two or more AEDs. Children with predominantly generalized seizures from genetic, structural epilepsies, like Dravet syndrome or Lennox-Gastaut syndrome, could also benefit from VNS Therapy., Significance: The results demonstrate that adjunctive VNS Therapy in children with drug-resistant epilepsy reduces seizure frequency and is well tolerated over a 2-year follow-up period. No new safety issues were identified. A post hoc analysis revealed a dose-response correlation for VNS in patients with epilepsy., (Wiley Periodicals, Inc. © 2014 International League Against Epilepsy.)

Individuals with Lennox-Gastaut syndrome (LGS) often do not respond to or become resistant to pharmacologic treatments. Ketogenic diets (KDs) and vagus nerve stimulation (VNS) are nonpharmacologic treatment options for these intractable patients. The classic KD, a high-fat, low-carbohydrate diet with 90% of calories derived from fat, has been used in the treatment of seizures for >90 years. About half of patients with LGS respond to the KD with a >50% reduction in seizures and some patients may achieve a >90% reduction. Vagus nerve stimulation therapy involves a surgically implanted generator that delivers intermittent electrical stimuli to the brain via an electrode wrapped around the left vagus nerve. It is utilized as adjunctive therapy for patients with drug-resistant epilepsy (including patients with LGS) who are not suitable candidates for resective surgery. Similar to the KD, about half of LGS patients respond to VNS therapy, with a >50% reduction in seizures, and the response may improve over time. Both the KD and VNS are options for patients with LGS., (Wiley Periodicals, Inc. © 2014 International League Against Epilepsy.)

Purpose:   Vagus nerve stimulation (VNS) provides partial relief of medically refractory partial seizures in a subset of patients. The optimal pattern of stimulation and the mechanism of the antiseizure effects are uncertain. Establishing the efficacy of VNS in an animal model of epilepsy would provide an experimental preparation with which to address these questions. We sought to determine whether VNS exerted antiseizure effects in the kindling model of epilepsy., Methods:   We implanted adult rats with bipolar stimulating electrodes in the right amygdala and VNS devices around the left vagus nerve. Following induction of kindling, electrographic seizure threshold (EST) was determined by quantifying the amygdala electrode current required to evoke a seizure. Once stable ESTs were established, VNS devices were programmed to deliver U.S. Food and Drug Administration (FDA)-approved, clinically used (standard) or an experimental (microburst) pattern of stimulation of variable intensity. VNS devices were programmed identically in control animals except that no current was delivered. EST was examined at 60 min and 1 week in the control and vagus nerve stimulated groups., Key Findings:   Significant reductions of EST values were detected in control animals when tested both 60 min and 1 week following device programming. Both clinically used and experimental patterns of VNS prevented the reduction of EST evident in control animals when tested either 60 min or 1 week after device programming., Significance:   These findings establish an experimental preparation with which to elucidate the antiseizure mechanisms of VNS and to determine patterns of VNS most effective at elevating seizure threshold., (Wiley Periodicals, Inc. © 2012 International League Against Epilepsy.)

To elucidate, in a pilot-study, whether noninvasive transcutaneous vagus nerve stimulation (t-VNS) is a safe and tolerable alternative treatment option in pharmacoresistant epilepsy. t-VNS was applied to 10 patients with pharmacoresistant epilepsies. Stimulation via the auricular branch of the vagus nerve of the left tragus was delivered three times per day for 9 months. Subjective documentation of stimulation effects was obtained from patients' seizure diaries. For a more reliable assessment of seizure frequency, we carried out prolonged outpatient video-electroencephalography (EEG) monitoring. In addition, computerized testing of cognitive, affective, and emotional functions was performed. Three patients aborted the study. Of the remaining seven patients, an overall reduction of seizure frequency was observed in five patients after 9 months of t-VNS. The noninvasive t-VNS stimulation is a safe and well-tolerated method for relatively long periods, and might be an alternative treatment option for patients with epilepsy., (Wiley Periodicals, Inc. © 2012 International League Against Epilepsy.)

We present an update of our experience with the ketogenic diet (KD) in patients with Dravet syndrome (DS) to evaluate the efficacy and tolerability and our short experience with vagus nerve stimulation (VNS) in the treatment of this syndrome. Between March 1, 1990 and May 31, 2007, 59 patients who met diagnostic criteria for DS were studied in our department. Twenty-four of them were placed on the KD and were followed up for a minimum of 2 years. Three patients were treated with VNS. Sixteen (66.6%) of 24 patients remained on the diet. Two patients (12.5%) became seizure free, 10 children (62.5%) had a 75-99% decrease in seizures, and the remaining 4 children (25%) had a 50-74% decrease in seizures. Six patients have been off the diet for >2 years; one of them is seizure free, two have sporadic seizures, and three, who abandoned the diet after 3 years of adhering to it, relapsed. As to the efficacy of VNS, two patients had a 50-74% decrease in seizures and in the other seizure frequency remained unchanged. The device was well tolerated in all patients without significant complications. Considering the severity and refractarity of seizures in patients with DS, the fact that 12 of 16 children who remained on the diet had a significant reduction in number of seizures shows that the KD is at present an interesting therapeutic option. VNS may be a good alternative treatment for DS., (Wiley Periodicals, Inc. © 2011 International League Against Epilepsy.)

Although many patients with medically refractory focal epilepsy are candidates for resective surgery, patients with multifocal epilepsy and symptomatic generalized epilepsy remain difficult to treat medically and surgically. Corpus callosotomy has been utilized since 1940 for the treatment of seizures, with reports of efficacy in multiple seizure types. Previous studies have demonstrated subsequent lateralization of bilateral/bisynchronous epileptiform activity following callosotomy. To investigate the efficacy of bilateral intracranial electroencephalographic studies immediately following corpus callosotomy, we retrospectively identified 26 patients who underwent corpus callosotomy at our center, 18 of whom had intracranial monitoring following corpus callosotomy. Five of the 18 had focal resections following intracranial electroencephalography (EEG). No patients were seizure free following callosotomy or resection. No differences in postoperative outcomes were seen between patients with intracranial EEG versus those without.

Vagus nerve stimulation (VNS) is a nonpharmacologic therapeutic option for patients with intractable epilepsy. Better clinical outcomes were recorded in nonfocal and Lennox-Gastaut syndrome (LGS). We conducted a 2-year, open label, prospective study to measure the seizure outcome of 26 VNS patients. The seizure numbers were assessed using clinician's global impression scale (CGI) and patient diaries. The average seizure reduction was 23% at the first year and 22% at the second year. Seizure reduction was more pronounced among patients with nonfocal than with focal epilepsy. The response rate was 50% at first year and 30% at the second year. The best CGI record for clinically significant improvement was 15% in the LGS group. The only statistically significant result was the reduction of the generalized tonic-clonic seizures (GTCS). The side-effect profile was good; however, the large number of mild and reversible effects influenced the stimulation parameters and thus probably the effectiveness of the therapy. We suggest that VNS is an optional treatment mostly in cases of therapy-resistant Lennox-Gastaut syndrome. Patients with GTCS may experience improvement such as reduction of seizure severity. We conclude that VNS is a safe neuromodulatory treatment, but future developments of neuromodulatory approaches are needed.

We studied the effects of vagus nerve stimulation (VNS) on eating seizures, which theoretically would be triggered by neural activity and signaling from organs innervated by the vagus nerve. Three adult patients with daily nonreflex and reflex eating seizures were studied; one patient also had hot-water seizures. One patient had bilateral polymicrogyria and two had normal magnetic resonance imaging (MRI) findings. All patients were submitted to VNS implantation and had at least 2 years of postimplantation follow-up. Final stimulation parameters were 2.0-2.5 mA, 500 micros, and 30 Hz. Eating seizures decreased 70-95% and nonreflex seizures decreased 0-40% after VNS. There was no improvement in hot-water seizures. VNS seems to be an especially useful treatment modality in patients with reflex eating seizures not amenable to resective surgery.

Purpose: Angelman syndrome (AS) commonly presents with epilepsy (>80%). The goal of this study was to examine the natural history and various treatments of epilepsy in AS in a large population., Methods: A detailed electronic survey containing comprehensive questions regarding epilepsy in AS was conducted through the Angelman Syndrome Foundation., Results: There were responses from 461 family members of individuals with AS, of whom 86% had epilepsy (60% with multiple seizure types), the most common being atonic, generalized tonic-clonic, absence, and complex partial. Partial-onset seizures only were reported in 11% of those with epilepsy. Epilepsy was most common among those with maternal deletions and unknown subtypes, with catastrophic epilepsies present in only these two subtypes. These epilepsies were refractory to medication, with only 15% responding to the first antiepileptic drug (AED). The most commonly prescribed AED were valproic acid and clonazepam, but lamotrigine and levetiracetam appeared to have similar efficacy and tolerability., Discussion: This is the largest study to date assessing epilepsy in AS. Although epilepsy in AS is considered a generalized epilepsy, there was a high prevalence of partial seizures. There are few previous data regarding the use of newer AED in AS, and the results of this study suggest that these newer agents, specifically levetiracetam and lamotrigine, may have efficacy similar to that of valproic acid and clonazepam, and that they appear to have similar or better side-effect profiles. Nonpharmacologic therapies such as dietary therapy and vagus nerve stimulation (VNS) also suggest favorable efficacy and tolerability, although further studies are needed.

Purpose: Vagus nerve stimulation (VNS) is used increasingly as adjunctive therapy for refractory epilepsy. Studies of VNS in children report mainly seizure frequency reduction as a measure of efficacy and clinical details are often scanty. We report our experience with VNS in children with refractory epilepsy and emphasize the positive effects of VNS in terms of seizure severity., Methods: We reviewed 26 consecutive children who had VNS with a minimum follow-up period of 18 months. We examined their clinical characteristics, seizure types, seizure frequency, epilepsy syndrome diagnosis, and response to VNS in terms of seizure frequency and seizure severity., Results: Fifty-four percent of patients responded to VNS with >or=50% seizure frequency reduction. Patients with Lennox-Gastaut syndrome (LGS) and tonic seizures had a higher responder rate; 78% (seven of nine patients) (p < 0.01). Status epilepticus (SE) episodes were reduced or ceased in the four patients with recurrent SE. Seizure severity, duration, and recovery time decreased in all responders. Increased alertness was reported in all responders and three nonresponders., Conclusion: Decreased seizure severity, recovery time, abolition of daytime drop attacks, and reduced hospitalization due to SE improved patients' lives over and above the benefit from seizure frequency reduction.