Hemispherotomy in children with electrical status epilepticus of sleep

Clinical features of unilateral multilobar and hemispheric polymicrogyria (PMG)-related epilepsy and seizure outcome with different treatment options

OBJECTIVE

To provide evidence for choosing surgical or nonsurgical treatment for epilepsy in patients with unilateral multilobar and hemispheric polymicrogyria (PMG).

METHODS

We searched published studies until September 2022 related to unilateral multilobar and hemispheric PMG and included patients who were followed up at the Pediatric Epilepsy Centre of Peking University First Hospital in the past 10 years. We summarized the clinical characteristics and compared the long-term outcomes after surgical or nonsurgical (anti-seizure medications, ASMs) treatment.

RESULTS

A total of 70 patients (49 surgical, 21 non-surgical) with unilateral multilobar and hemispheric PMG were included. The median age at epilepsy onset was 2.5 years (1.0-4.1). The most common seizure types were focal and atypical absence seizures. In the whole cohort, 87.3% had hemiparesis and 67.1% had electrical status epilepticus during slow sleep (ESES). There were significant differences in age at epilepsy onset, extent of lesion, and EEG interictal discharges between the two groups. At the last follow-up (median 14.1 years), the rates of seizure-freedom (81.6% vs. 57.1%, p = 0.032) and ASM discontinuation (44.4% vs. 6.3%, p = 0.006) were higher in the surgical group than in the nonsurgical group. Patients in the surgical group had a higher rate of seizure-freedom with complete resection/disconnection than with subtotal resection (87.5% vs. 55.6%, p = 0.078), but with no statistically significant difference. In the nonsurgical group, more extensive lesions were associated with worse seizure outcomes. Cognition improved postoperatively in 90% of surgical patients.

SIGNIFICANCE

In patients with unilateral multilobar and hemispheric PMG, the age of seizure onset, the extent of the lesion and EEG features can help determine whether surgery should be performed early. Additionally, surgery could be more favorable for achieving seizure freedom and cognitive improvement sooner.

PLAIN LANGUAGE SUMMARY

We aim to summarize clinical characteristics and compare the long-term outcomes after surgical and nonsurgical (ASM) treatment to provide a basis for treatment decisions for patients with unilateral multilobar and hemispheric polymicrogyria (PMG)-related epilepsy. We found that patients with unilateral hemispheric and multilobar PMG had significantly higher rates of seizure freedom and ASM discontinuation with surgical treatment than with nonsurgical treatment. In the surgical group, seizure outcomes were better in patients treated with complete resection/disconnection than in those treated with subtotal resection, but the difference was not statistically significant.

Surgical treatment of epileptic encephalopathy with spike-and-wave activation in sleep: A systematic review and meta-analysis

OBJECTIVE

Epileptic Encephalopathy / Developmental Epileptic Encephalopathy with spike-and-wave activation during sleep (EE/DEE-SWAS) is a self-limiting childhood epilepsy syndrome but may cause permanent neurocognitive impairment. Surgical interventions have been controversial in the treatment of EE/DEE-SWAS. This systematic review aims to evaluate the efficacy of various surgical procedures on the outcomes of EE/DEE-SWAS.

METHODS

A systematic review was performed per the PRISMA guidelines. A total of 14 retrospective studies were identified, comprising 131 cases of EE/DEE-SWAS treated with epilepsy surgery. The review analyzed presurgical data, surgical interventions, as well as outcomes related to seizures, EEG, and neuropsychological assessments.

RESULTS

Epilepsy surgery was successfully performed in 131 cases with minor complications. The average age was 2.6 years at seizure onset and 5.0 years at diagnosis of SWAS. Excellent seizure control (Engel I and II) was achieved in 80.6 %, 78.6 %, 77.4 % and 27.2 % of patients receiving hemispherectomies, focal resections, multiple subpial transections (MSTs), and corpus callosotomies (CCTs), respectively. EEG SWAS resolution was seen in 79.7 % of hemispherectomy cases, 78.6 % in focal resections, 63.9 % in MSTs, and 8.3 % in CCTs. Neurocognitive and behavioral improvement was noted in 58.0 %, 71.4 %, 58.3 % and 16.7 % for patients receiving hemispherectomies, focal resections, MSTs, and CCTs, respectively. A correlation between improved seizure control and SWAS resolution was observed with improved neuropsychological outcomes.

CONCLUSION

Epilepsy surgery is a safe and effective treatment for carefully selected children with drug-resistant EE/DEE-SWAS. Patients who underwent epilepsy surgery had reduction of seizure burden, SWAS resolution and improvements in neurocognitive and behavioral function.

Continuous Spike-Waves during Slow Sleep Today: An Update

In the context of childhood epilepsy, the concept of continuous spike-waves during slow sleep (CSWS) includes several childhood-onset heterogeneous conditions that share electroencephalograms (EEGs) characterized by a high frequency of paroxysmal abnormalities during sleep, which have negative effects on the cognitive development and behavior of the child. These negative effects may have the characteristics of a clear regression or of a slowdown in development. Seizures are very often present, but not constantly. The above makes it clear why CSWS have been included in epileptic encephalopathies, in which, by definition, frequent EEG paroxysmal abnormalities have an unfavorable impact on cognitive functions, including socio-communicative skills, causing autistic features, even regardless of the presence of clinically overt seizures. Although several decades have passed since the original descriptions of the electroclinical condition of CSWS, there are still many areas that are little-known and deserve to be further studied, including the EEG diagnostic criteria, the most effective electrophysiological parameter for monitoring the role of the thalamus in CSWS pathogenesis, its long-term evolution, the nosographic location of Landau-Kleffner syndrome, standardized neuropsychological and behavioral assessments, and pharmacological and non-pharmacological therapies.

Epilepsy Surgery for Cognitive Improvement in Epileptic Encephalopathy

Epileptic encephalopathies are defined by the presence of frequent epileptiform activity that causes neurodevelopmental slowing or regression. Here, we review evidence that epilepsy surgery improves neurodevelopment in children with epileptic encephalopathies. We describe an example patient with epileptic encephalopathy without drug refractory seizures, who underwent successful diagnostic and therapeutic surgeries. In patients with epileptic encephalopathy, cognitive improvement alone is a sufficient indication to recommend surgical intervention in experienced centers.

The Effectiveness and Safety of Hormonal Combinations of Antiepileptic Drugs in the Treatment of Epileptic Electrical Continuity in Children during Sleep: A Meta-Analysis

Objective

A systematic evaluation of the efficacy of hormones in combination with antiepileptic drugs (AEDs) compared to AEDs alone in the treatment of children with encephalopathy related to status epilepticus during slow sleep (ESES). This study provides an evidence-based approach to the treatment of children with ESES.

Materials and Methods

To find all relevant studies published before March 2022, we searched PubMed, Embase, Web of Science, Clinical Trials, Cochrane Library, CNKI, and Wanfang databases. We explore the difference between AEDs combined with hormones and AEDs alone for ESES treatment. All outcome data, including Wechsler Intelligence Scale for Children, the effective rate, EEG discharges, and adverse effects rate (AER), were compared using Review Manager 5.3.

Results

There were 805 patients in this study's seven investigations, including 403 in the experimental group and 402 in the control group. Meta-analysis showed that after treatment, compared with the AEDs alone group, the hormone combined with AEDs. The difference in clinical improvement rate [RR = 1.25, 95% CI (1.15, 1.36), p < 0.00001], electroencephalographic (EEG) discharge improvement rate [RR = 1.31, 95% CI (1.22, 1.41), p < 0.00001], and cognitive intelligence score [SMD = 1.02, 95% CI (0.76, 1.28), p < 0.00001] was statistically significant. The differences were statistically significant in terms of 0.00001; the incidence of adverse reactions was higher in the hormone combined with AEDs group than in the AEDs group alone, and the differences were statistically significant [RR = 4.13, 95% CI (1.06, 16.13), p < 0.01], and all adverse reactions improved or disappeared after discontinuation of the drug.

Conclusions

The combination of hormones with AEDs for the treatment of epileptic electrical continuity in sleep has advantages over AEDs alone in terms of controlling seizures, improving EEG abnormalities, and improving cognition. The combination of hormones with AEDs has advantages over AEDs alone in controlling seizures, improving EEG abnormalities, and improving cognition and is relatively safe.

Children's Neurological Status Epilepticus and Poor Prognostic Factors through Electroencephalogram Image under Composite Domain Analysis Algorithm

This study aimed to analyze the application of composite domain analysis algorithm for electroencephalogram (EEG) images of children with epilepsy and to investigate the risk factors related to poor prognosis. 70 children with neurological epilepsy admitted to the hospital were selected as the research objects. Besides, the EEG of the children during the intermittent and seizure phases of epilepsy were collected, so as to establish a composite domain analysis algorithm model. Then, the model was applied in EEG analysis. The clinical disease type and prognosis of children were statistically analyzed, and the risk factors that affected the prognosis of children were investigated. The results showed that the EEG signal values of the detail coefficients (d51 and d52) and the approximate coefficient (c5) during the epileptic seizure period were higher markedly than the signal values of the epileptic intermittent period; the EEG signal of the epileptic intermittent period was a transient waveform, which appeared as sharp waves or spikes. The EEG signal of epileptic seizures was continuous, with a composite waveform of sharp waves and spikes, and the change amplitude of the wavelet envelope spectrum during epileptic seizures was also higher hugely than that of intermittent epilepsy. The accurate identification rate, specificity, and sensitivity of EEG analysis with the composite domain algorithm were higher than those without the algorithm. Among the five types of epileptic seizures in children, the proportion of systemic tonic-clonic status was the largest, and the proportion of myoclonic status was equal to that of complex partial epileptic status, both of which were relatively small. The proportion of children with a better prognosis was 75.71% (53/70), which was higher than those with a poor prognosis 24.29% (17/70). Abnormal imaging examination (odds ratio (OR) = 3.823 and 95% confidence interval (CI) = 1.643–8.897); seizure duration greater than 1 hour (OR = 1.855 and 95% CI = 1.076–3.199); C-reactive protein (CRP) (OR = 5.089 and 95% CI = 1.507–17.187); and abnormal blood glucose (OR = 3.077, 95%CI = 1.640–5.773) were all independent risk factors for poor prognosis (all P < 0.05). The composite domain analysis algorithm was helpful for clinicians to find the difference in the EEG signals between the epileptic seizure period and the epileptic intermittent period in a short time, thereby improving the doctor's analysis of the results, which could reflect its marked superiority. In addition, abnormal imaging examinations, convulsion duration greater than 1 hour, CRP, and abnormal blood glucose were independent risk factors for poor prognosis in children. Therefore, the invasion of related risk factors could be reduced clinically by prognostic review with medical advice, attention to food safety and hygiene, and improvement of children's immunity.

Epilepsy Surgery: Special Circumstances

Epilepsy surgery has proven to be very effective in treating refractory focal epilepsies in children, producing seizure freedom or partial seizure control well beyond any other medical or dietary therapies. While surgery is mostly utilized in certain clinical phenotypes, either based on the location such as temporal lobe epilepsy, or based on the presence of known epileptogenic lesions such as focal cortical dysplasia, tumors or hemimegalencephaly, there is a growing body of evidence to support the role of surgery in other patients' cohorts that were classically not thought of as surgical candidates. These include patients with rare genetic disorders, electrical status epilepticus in sleep, status epilepticus and the very young patients. Furthermore, epilepsy surgery is not considered as a "last resort" as seizure and cognitive outcomes of surgery are considerably better when done earlier rather than later in relation to the time of onset of epilepsy and age of surgery especially in the context of known focal cortical dysplasia. This article examines the accumulating evidence of the utility of epilepsy surgery in these special circumstances.

Corpus callosotomy in pediatric patients with non-lesional epileptic encephalopathy with electrical status epilepticus during sleep

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Corpus callosotomy (CC) was performed in 3 pediatric patients with refractory epileptic encephalopathy with ESES.

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IQ was improved after CC with complete resolution of ESES in one patient.

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Developmental regression ceased after CC with worthwhile seizure reduction and temporary improvement of ESES in 2 patients.

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Epileptiform discharges disappeared or became lateralized after CC.

Epileptic encephalopathy with electrical status epilepticus during sleep (ESES) is often refractory to medical treatment and leads to poor cognitive outcomes. Corpus callosotomy may be an effective treatment option for drug-resistant ESES with no focal etiology. We retrospectively identified three patients who underwent corpus callosotomy for drug-resistant ESES in our institution. Electroencephalography (EEG) findings and cognitive functions were evaluated before surgery, at 3 months, 6 months, 1 year, and 2 years after surgery. Age at surgery was 6 years 10 months, 7 years 9 months, and 8 years 4 months, respectively. Period between the diagnosis of ESES and surgery ranged from 7 to 25 months. All patients had no obvious structural abnormalities and presented with cognitive decline despite multiple antiseizure medications and steroid therapies. One patient showed complete resolution of ESES and an improvement of intelligence quotient after surgery. Epileptiform EEG was lateralized to one hemisphere after surgery and spike wave index (SWI) was decreased with moderate improvement in development and seizures in the other 2 patients. SWI re-exacerbated from 6 months after surgery, but without subsequent developmental regression in these 2 patients. Corpus callosotomy may become an important treatment option for drug-resistant ESES in patients with no structural abnormalities.

Electrical Status Epilepticus During Slow-wave Sleep (ESES): Current Perspectives

Electrical status epilepticus during slow-wave sleep (ESES) is an epilepsy syndrome with sleep-induced epileptic discharges and acquired impairment of cognition or behavior. Since the disease’s original description in 1971, no clear consensus has emerged on diagnostic criteria or optimal treatment. The treatment of ESES can be challenging, often including numerous antiepileptic drugs, immunomodulatory agents, and even surgical interventions. There is little evidence to guide treatment because only retrospective studies and case reports on the efficacy of treatment of ESES are present in literature. In this paper, we aim to analyze the etiopathogenesis of ESES in the new genetic era and to evaluate the treatment modalities in accordance with the genetic data and electroclinic spectrum of ESES.

A follow-up study in children with status epilepticus during sleep: From clinical spectrum to outcome

PURPOSE

To evaluate the correlation between clinical spectrum and therapeutic outcomes and neuropsychological deficits in children with status epilepticus during sleep (SES).

METHODS

The clinical spectrum of patients with SES was defined as follows: status epilepticus of benign childhood epilepsy with centro-temporal spikes (SEBECTs), atypical benign focal epilepsy during childhood (ABFEC), non-idiopathic focal epilepsy (NIFE), and Landau-Kleffner syndrome (LKS). SES cases were divided into 4 groups according to neuropsychological findings before treatment: developmental delay/intellectual disability (DD/ID), cognitive impairment (CI), attention deficit and/or hyperactivity behaviors (AHD), and normal group (NG). The therapeutic outcomes were classified into 3 groups: satisfactory response, recurrence, and seizure control.

RESULTS

A total of 39 cases (24 males and 15 females) were recruited, including 3 cases with SEBECTs, 26 with ABFEC, 8 with NIFE [2 with focal cortical dysplasia (FCD)], and 2 with LKS. There were 7 patients in the DD/ID group, 8 in the CI group, 19 in the AHD group, and 5 in the NG group. Neuropsychological outcomes were significantly different among clinical spectrum (P < 0.001), and neuropsychological deficits frequently occurred in the ABFEC group or in the NIFE group. Besides, 18 patients in the satisfactory group had satisfactory response to medicine or surgery (2 out of 18 cases with FCD), whereas recurrence was observed at least one session within one year in 16 cases in the recurrence group, and no improvement in spike-wave index and cognition/behavior was noted in 5 patients in the seizure control group, although seizure could be controlled. There were significant differences in therapeutic outcomes among clinical spectrum (P = 0.041), with the worst outcomes in the NIFE group (only 1 out of 8 with satisfactory good response).

CONCLUSIONS

It is important to categorize patients with SES into epilepsy syndromes, including SEBECTs, ABFPEC, NIFE, and LKS; the clinical spectrum may be a significant determinant to influence the outcomes of SES, including neuropsychological deficits and therapeutic outcomes.

Association of iron supplementation and deworming with early childhood development: analysis of Demographic and Health Surveys in ten low- and middle-income countries

PURPOSE

We assessed the associations of iron supplementation and deworming separately or combined with improved early childhood development (ECD) status.

METHODS

Cross-sectional data were analyzed for 29,729 children aged 36-59 months surveyed using the Demographic and Health Surveys in ten low- and middle-income countries, where iron supplementation and deworming are recommended by the World Health Organization. In each country, we estimated linear regression models for the effects of iron supplementation and deworming individually or combined on the Early Childhood Development Index (ECDI) z score, and whether this association differed between various ECD domains and the sex and residence of the child. Estimates were pooled using random-effects meta-analyses.

RESULTS

Compared with receiving neither of the two interventions, iron supplementation plus deworming was associated with an increased ECDI z score (β = 0.13, 95% confidence interval (CI) 0.03-0.22, p = 0.009), particularly in rural residences. However, iron supplementation and deworming, individually, were not associated with the ECDI z score. Iron supplementation plus deworming was associated with higher odds of on-track development in literacy-numeracy (OR = 1.57, 95% CI 1.24-2.01, p < 0.001) and learning domains (OR = 1.27, 95% CI 1.09-1.48, p = 0.003), but not with development in the social-emotional and physical domains.

CONCLUSION

Iron supplementation plus deworming, particularly for populations who are more susceptible to iron deficiency and intestinal worm infections, could be an important intervention for improving ECD. These findings may inform the argument for the necessity of implementing iron supplementation and deworming for preschool-age children.

Pediatric Epilepsy Surgery in Focal and Generalized Epilepsy: Current Trends and Recent Advancements

For a subset of children with medically intractable epilepsy, surgery may provide the best chances of seizure freedom. Whereas the indications for epilepsy surgery are commonly thought to be limited to patients with focal epileptogenic foci, modern imaging and surgical interventions frequently permit successful surgical treatment of generalized epilepsy. Resection continues to be the only potentially curative intervention; however, the advent of various neuromodulation interventions provides an effective palliative strategy for generalized or persistent seizures. Although the risks and benefits vary greatly by type and extent of intervention, the seizure outcomes appear to be uniformly favorable. Advances in both resective and nonresective surgical interventions provide promise for improved seizure freedom, function, and quality of life. This review summarizes the current trends and recent advancements in pediatric epilepsy surgery from diagnostic workup and indications through surgical interventions and postoperative outcomes.

Pharmacological treatment for continuous spike-wave during slow wave sleep syndrome and Landau-Kleffner Syndrome

BACKGROUND

Continuous spike-wave during slow wave sleep syndrome (CSWS) and Landau-Kleffner syndrome (LKS) are two epileptic encephalopathies that present with neurocognitive regression, aphasia, and clinical seizures, typically presenting in children around five years of age. The pathophysiology of these conditions is not completely understood. Some studies suggest a common origin for both. No systematic reviews have assessed the efficacy of pharmacological interventions for these conditions.

OBJECTIVES

To assess the benefit and adverse effects of pharmacological interventions for the treatment of CSWS and LKS.

SEARCH METHODS

On 8 September 2020, we searched the Cochrane Register of Studies (CRS Web) and MEDLINE Ovid (1946 to September 04, 2020). We applied no language restrictions. CRS Web includes randomised or quasi-randomised, controlled trials from CENTRAL, PubMed, Embase, ClinicalTrials.gov, and the World Health Organization International Clinical Trials Registry Platform.

SELECTION CRITERIA

Randomised controlled trials, quasi-randomised controlled trials, and cluster-randomised trials comparing antiepileptic drugs alone, or with steroids or intravenous immunoglobulins, or both versus other antiepileptic drugs, or placebo, or no treatment, administered to children with CSWS and LKS. We planned to compare treatments for the two conditions separately.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies identified by the search strategy for inclusion. The primary outcomes considered in this review were neuropsychological-neurolinguistic functions.

MAIN RESULTS

Our search strategy yielded 18 references. Two review authors independently assessed all references. We did not find any completed studies to include. We identified one ongoing trial, which was terminated because of lack of enrolment.

AUTHORS' CONCLUSIONS

There was no evidence from trials to support or refute the use of pharmacological treatment for continuous spike-wave during slow wave sleep syndrome or Landau-Kleffner syndrome. Well-designed randomised controlled trials are needed to inform practice.

Treatment strategies for encephalopathy related to status epilepticus during slow sleep, a narrative review of the literature

Encephalopathy related to Status Epilepticus during slow Sleep (ESES) is an age-dependent syndrome characterized by the appearance of neuropsychological and behavioral disorders associated with extreme activation of epileptic activity during sleep. The major goal of therapy in ESES is to prevent neuropsychological deficits. Effective therapy to reduce seizures and resolve the EEG pattern of status epilepticus during sleep (SES) may be crucial to improve long-term prognosis. However, whether to improve neurodevelopmental deficits by suppressing or eliminating SES remains unknown. The purpose of this article is to review current therapeutic options in ESES, in order to provide better alternatives. Treatment options consist of antiepileptic drugs, steroids, immunoglobulins, the ketogenic diet, and surgery. Maybe therapy targeted mechanisms can be developed with deep insight into the etiology of ESES.

Examining the Utility of Resective Epilepsy Surgery in Children With Electrical Status Epilepticus in Sleep: Long Term Clinical and Electrophysiological Outcomes

Background: Electrical Status Epilepticus in Sleep (ESES) is an epileptic encephalopathy syndrome characterized by infrequent clinical seizures and prominent interictal burden during slow wave sleep associated with cognitive deficits and behavioral dysfunction. Medical treatment with anti-epileptic drugs is often unsuccessful. Resective surgery may be a valuable option in carefully selected patients. This case series aims to describe the indications, long term results and utility of resective surgery for ESES.

Methods: Information on 14 patients who underwent surgery for epilepsy and ESES at the Children's Hospital of Wisconsin between 2007 and 2017 is included. Clinical, electrographic and neuropsychological features and outcomes are described in detail.

Results: The most common pathology was encephalomalacia due to perinatal middle cerebral artery stoke (5/14). Twelve patients had imaging findings of perinatal pathologies; however, two patients had normal magnetic resonance imaging. Surgery was performed to control refractory epilepsy in eight patients. Six patients had no clinical seizures for 1–6 years prior to surgery, one of which had no known clinical seizures at all. All showed cognitive declines (6/14) or impairment (8/14) on neuropsychological assessments, and surgery was suggested to minimize further cognitive declines. The most common surgical procedure was hemispherotomy (10/14). Temporo-parieto-occipital disconnection, frontal lobectomy, parieto-occipital resection, and limited corticectomy were also used, with good outcomes for the first three procedures. Clinical follow up mean was 4.4 years and 12 patients had excellent seizure outcome. Electroencephalography (EEG) follow up mean was 3 years and ESES resolved in 12/14 patients. All patients completed post-surgical neuropsychological evaluation with mean follow-up of 17.46 months.

Conclusions: Resective surgery is an effective treatment for selected cases of ESES, producing long term seizure freedom, resolution of ESES and stabilization of cognitive and behavioral functioning in most patients. Our case series is the largest single center cohort description addressing resective surgery for ESES. Outcomes in this sample suggest that good long-term seizure, EEG and cognitive/behavioral outcomes can be achieved in patients with normal brain imaging and in limited lobar or multi-lobar resections. Moreover, patients with ESES and very infrequent clinical seizures can benefit from surgery with stabilization of cognitive and behavioral functioning.

Outcome after hemispherotomy in patients with intractable epilepsy: Comparison of techniques in the Italian experience

OBJECTIVE

The objective of the study was to evaluate clinical characteristics and outcome of hemispherotomy in children and adolescents with hemispheric refractory epilepsy in an Italian cohort of patients.

METHODS

We retrospectively evaluated the clinical course and outcome of 92 patients with refractory epilepsy who underwent hemispherotomy in three Italian epilepsy centers between 2006 and 2016. Three different approaches for hemispherotomy were used: parasagittal, modified parasagittal, and lateral.

RESULTS

Mean age at epilepsy onset was 1.8 ± 2.51 years, and mean duration of epilepsy prior to surgery was 7.4 ± 5.6 years. Mean age at surgery was 9.2 ± 8.0 years. After a mean follow-up of 2.81 ± 2.4 years, 66 of 90 patients (two lost from follow-up, 73.3%) were seizure-free (Engel class I). The etiology of epilepsy was related to acquired lesions (encephalomalacia or gliosis) in 44 patients (47.8%), congenital malformations (cortical dysplasia, hemimegalencephaly, other cortical malformations) in 38 (41.3%), and progressive conditions (Rasmussen or Sturge-Weber syndrome) in 10 patients (10.9%). Regarding seizure outcome, we could not identify statistically significant differences between vertical and lateral approaches (p = 0.154). Seizure outcome was not statistically different in patients with congenital vs acquired or progressive etiologies (p = 0.43). Acute postoperative seizures (APOS) correlated with poor outcome (p < 0.05). On multivariate analysis, presurgical focal to bilateral tonic-clonic seizures (Odds Ratio (OR) = 3.63, 95% Confidence Interval (CI): 1.86-15.20, p = 0.048) independently predicted seizure recurrence. Twenty-one patients (22.8%) exhibited postoperative complications, with no unexpected and persistent neurological deficit. More than 50% of the patients completely tapered drugs.

SIGNIFICANCE

Our data confirm hemispherotomy to be a safe and effective procedure in patients with drug resistant epilepsies due to hemispheric lesions. Presurgical focal to bilateral tonic-clonic seizures are the strongest predictor of seizure recurrence after surgery, independently from the type of hemispherotomy.

Scalp-recorded high-frequency oscillations in childhood epileptic encephalopathy with continuous spike-and-wave during sleep with different etiologies

OBJECTIVE

To investigate high-frequency oscillations (HFOs) in epileptic encephalopathy with continuous spike-and-wave during sleep (CSWS) with different etiologies.

METHODS

Twenty-one CSWS patients treated with methylprednisolone were divided into structural group and genetic/unknown group. Comparisons were made between the two etiological groups: selected clinical variables including gender, age parameters, seizure frequencies and antiepileptic drugs; distribution of HFOs in pre-methylprednisolone electroencephalography (EEG) and percentage changes of HFOs and spikes after methylprednisolone treatment.

RESULTS

There were 7 patients (33%) in structural group and 14 patients (68%) in genetic/unknown group. No significant difference was found between the two groups regarding selected clinical variables. HFOs were found in 12 patients in pre-methylprednisolone EEG. The distribution of HFOs was focal and accordant with lesions in 5 of structural group, and it was also focal but in different brain regions in 7 of genetic/unknown group. The percentage reduction of total HFOs and spikes was 81% (158/195) and 19% (1956/10,037) in structural group, while 98% (315/323) and 55% (6658/12,258) in genetic/unknown group after methylprednisolone treatment.

CONCLUSION

The etiologies had no distinct correlation with some clinical characteristics in CSWS. HFOs recorded on scalp EEG might not only be used as makers of seizure-onset zone (SOZ), but also have association with functional disruption of brain networks. Both HFOs and spikes reduced more in genetic/unknown patients than that in structural patients after methylprednisolone treatment and HFOs were more sensitive to treatment than spikes.