Long-term outcomes of epilepsy surgery in 85 pediatric patients followed up for over 10 years: a retrospective survey

How are they doing as adults? Psychosocial and socioeconomic outcomes 11-30 years after pediatric epilepsy surgery

OBJECTIVE

Pediatric epilepsy surgery yields cure from epilepsy or complete seizure control with continued medication in many patients early in life. This study aimed to evaluate the long-term (>10 years) psychosocial and socioeconomic outcomes of pediatric epilepsy surgery and examine the role of comorbid disability, type of surgery, seizure freedom, and age at surgery.

METHODS

A novel ad hoc parent/patient questionnaire was used to assess educational and occupational attainment, marital/familial status, mobility, and other outcomes in patients who underwent unilobar or multilobar surgery for drug-refractory epilepsy during their childhood. The questionnaire also captured information on comorbid disability.

RESULTS

Of the 353 eligible patients, 203 could still be contacted and 101 of these (50%) returned appropriately filled-in questionnaires (follow-up intervals: 11-30 [mean: 19.6] years). The cure from epilepsy rate was 53%. Type of surgery was strongly confounded by comorbid disability. Patients with comorbid disabilities had significantly lower rates of regular school degrees, gainful employment, marriage, and driving license (N = 29; 12%, 4%, 0%, 3%) compared with non-disabled patients (N = 69; 89%, 80%, 43%, and 67%, respectively). Patients achieved lower school degrees than their siblings and parents. Non-disabled seizure-free patients had better employment and mobility outcomes compared with non-seizure-free patients. Age at surgery (<10 vs. ≥10 years of age) did not have any effect on any outcome in patients with preschool seizure onset.

SIGNIFICANCE

Pediatric epilepsy surgery can lead to permanent relief from epilepsy in many patients, but comorbid disability strongly impacts adult life achievement. In non-disabled patients, favorable outcomes in academic, occupational, marital, and mobility domains were achieved, approaching respective rates in the German population. Complete seizure freedom had additional positive effects on employment and mobility in this group. However, in case of chronic comorbid disability the overall life prospects may be limited despite favorable seizure outcomes.

Outcomes of resective surgery in pediatric patients with drug-resistant epilepsy: A single-center study from the Eastern Mediterranean Region

OBJECTIVE

Epilepsy surgery is widely accepted as an effective therapeutic option for carefully selected patients with drug-resistant epilepsy (DRE). There is limited data on the outcome of epilepsy surgery, especially in pediatric patients from the Eastern Mediterranean region. Hence, we performed a retrospective study examining the outcomes of resective surgery in 53 pediatric patients with focal DRE.

METHODS

Patients with focal DRE who had undergone epilepsy surgery were included in the present study. All patients underwent a comprehensive presurgical evaluation. Postoperative seizure outcomes were classified using the Engel Epilepsy Surgery Outcome Scale.

RESULTS

After surgery, 33 patients (62.2%) were Class I according to the Engel classification of surgical outcomes; eight patients (15.0%) were Class II, 11 (20.7%) were Class III, and one (1.8%) was Class IV. The relationships of presurgical, surgical, and postsurgical clinical variables to seizure outcomes were compared. Older age at seizure onset, older age at the time of surgery, the presence of focal to bilateral tonic-clonic seizures, seizure duration over 2 minutes, unsuccessful treatment with three or fewer antiseizure medications, lesions confined to one lobe (as demonstrated via magnetic resonance imaging [MRI]), surgical site in the temporal lobe, and histopathology including developmental tumors were significantly linked to an Engel Class I outcome. A univariate analysis of excellent surgical outcomes showed that lateralized semiology, localized interictal and ictal electroencephalogram (EEG) discharges, lateralized single-photon emission computed tomography and positron emission tomography findings, and temporal lobe resections were significantly related to excellent seizure outcomes.

SIGNIFICANCE

The results of our study are encouraging and similar to those found in other centers around the world. Epilepsy surgery remains an underutilized treatment for children with DRE and should be offered early.

Seizure outcomes after resection of primary brain tumors in pediatric patients: a systematic review and meta-analysis

PURPOSE

Primary brain neoplasms are the most common solid tumors in pediatric patients and seizures are a common presenting symptom. Surgical intervention improves oncologic outcomes and seizure burden. A better understanding of factors that influence seizure outcomes in the surgical management of primary brain tumors of childhood can guide treatment approach thereby improving patient quality of life.

METHODS

We performed a systematic analysis using articles queried from PubMed, EMBASE, and Cochrane published from January 1990 to August 2022 to determine predictors of seizure outcomes in pediatric patients undergoing resection of primary brain tumors.

RESULTS

We identified 24 retrospective cohort studies, one prospective cohort study, and one mixed retrospective and prospective study for the systematic analysis. A total of 831 pediatric patients were available for analysis. 668 (80.4%) patients achieved seizure freedom after surgery. Complete tumor resection increased the likelihood of a seizure-free (Engel I) outcome compared to subtotal resection (OR 7.1, 95% CI 2.3-21.9). Rates of Engel I seizure outcomes did not significantly differ based on factors such as age at seizure onset, duration of epilepsy, gender, tumor laterality, or age at surgery, but trended towards significance for improved outcomes in temporal lobe tumors.

CONCLUSION

Primary brain tumors in the pediatric population are commonly associated with seizures. Resection of these lesions reduces seizure burden and is associated with high rates of seizure freedom. Complete resection, compared to subtotal resection, significantly increases the likelihood of seizure-free outcomes.

Clinical adult outcome 11-30 years after pediatric epilepsy surgery: Complications and other surgical adverse events, seizure control, and cure of epilepsy

OBJECTIVE

Pediatric epilepsy surgery promises seizure freedom or even cure of epilepsy. We evaluated the long-term (≥10 years) adult clinical outcome including surgery-related adverse events and complications, which are generally underreported.

METHODS

A monocentric, single-arm, questionnaire study in now adult patients who underwent epilepsy surgery during childhood. A novel ad hoc parental/patient questionnaire, which addressed diverse outcome domains was applied.

RESULTS

From a total of 353 eligible patients, 203 could be contacted (3 patients died of causes unknown) and 101 (50%) returned appropriately filled-in surveys. No evidence for a survey-response bias was found. The rate of surgical complications according to the patient records was 9%. As regards the survey, half of the parents/patients reported surgical adverse events (expected and unexpected issues) and one-third reported permanent aversive sequels. Two-thirds of the patients were seizure-free during the last year before follow-up; 63% were Engel class 1A; favorable seizure outcomes (including auras only) were obtained in 73%; and 54% were seizure-free and off antiseizure medicine (ASM), that is, cured of epilepsy. In non-seizure-free patients, seizure relapse occurred at any time during the follow-up interval but 87% of those with a seizure-free first postoperative year were seizure-free at follow-up. One patient experienced a seizure relapse during the ASM withdrawal trial but became seizure-free again with ASMs. Eleven patients reported an increased number of ASMs as compared to the time before surgery. Earlier focal surgery did not affect the long-term clinical outcome.

SIGNIFICANCE

Pediatric epilepsy surgery was capable of curing epilepsy in about one-half of the children and to significantly control seizures in about three-fourths. Long-term success of focal surgery did not depend on age at surgery or duration of epilepsy. Surgical adverse events including complications may be underreported and must be assessed more thoroughly.

Paediatric epilepsy surgery: Techniques and outcomes

Epilepsy is a neurological condition characterised by recurrent and persistent seizures. For paediatric patients, achieving early seizure freedom can have positive impacts on cognition, development, social integration and mental health, leading to improved quality of life. In general, one third of patients with epilepsy are refractory to medication; for these patients, epilepsy surgery may offer the only chance for improved seizure control. Epilepsy surgery as a therapeutic intervention has become increasingly accepted in the past few decades, with more diverse options available (including neuromodulatory and minimally invasive techniques). In this context, we discuss here the pre-operative workup for paediatric patients with medically refractory epilepsy and provide an updated review on current and emerging surgical therapies for this condition. We also discuss the clinical, neuropsychological, quality of life and economic impacts of epilepsy surgery.

Long-term seizure outcomes in patients with hypothalamic hamartoma treated by stereotactic radiofrequency thermocoagulation

OBJECTIVE

To investigate long-term seizure outcomes in patients with hypothalamic hamartoma (HH) following stereotactic radiofrequency thermocoagulation (SRT).

METHODS

A total of 131 patients with HH who underwent SRT and were followed for at least three years after the last SRT were enrolled. Seizure outcomes were evaluated for gelastic seizures (GS) and other types of seizures (nGS) separately using the International League Against Epilepsy classification. Classes 1 and 2 were considered seizure-free. Kaplan-Meier survival analyses were used to estimate the proportion remaining seizure-free after the first and last SRTs. Risk factors relating to outcomes were analyzed by log-rank tests and a multivariate Cox proportional hazards model.

RESULTS

Reoperation was performed in 34 patients (26.2%). Median total follow-up was 61 (range, 36-202) months. Seizure freedom was obtained in 116 patients (88.6%) for GS and 85 of 108 patients (78.7%) for nGS at the last follow-up. Mean GS-free survival times improved from after the first (64.1 [95%CI 57.3-70.9] months) to after the last SRT (80.2 [95%CI 75.7-84.8] months). About 90% of GS recurrences after the first SRT were found within 6 months, though a few patients recurred more than 2 years after the first SRT. On the other hand, mean nGS-free survival times after the first and last SRTs were not different between after the first SRT (84.4 [95%CI 73.0-90.7] months) and after the last SRT (83.1 [95%CI 74.1-92.0] months). There was no factor related to GS outcomes, but the significant factor for nGS-free survival after the last SRT was multiple previous treatments (p=0.01, hazard ratio=15.65, 95%CI 1.79-137.16).

SIGNIFICANCE

The last SRT was almost equivalent to achieving complete disconnection of HHs from the hypothalamus according to our strategy. Considering the epileptogenic network, GS outcomes depend on complete disconnection, whereas nGS outcomes are not affected by surgical factors but independency of secondary epileptogenesis.

Epilepsy surgery: Late seizure recurrence after initial complete seizure freedom

OBJECTIVE

This study was undertaken to improve understanding of late relapse following epilepsy surgery in pharmacoresistant epilepsy.

METHODS

Retrospective comparison was made of 99 of 1278 patients undergoing surgery during 1999-2015 with seizure relapses after at least 2 years of complete seizure freedom with matched controls experiencing continued long-term seizure freedom. Univariate and multivariate analyses were performed.

RESULTS

With a mean follow-up of 9.7 years, mean time to seizure relapse was 56.6 months. In multivariate analysis, incomplete resection based on magnetic resonance imaging (MRI), bilateral lesions on preoperative MRI, and epilepsy onset in the first year of life carried a significantly higher risk of late relapse. In patients with late relapse, additional functional imaging with positron emission tomography had been performed significantly more often. Although the differences were not significant in multivariate analysis, doses of antiepileptic drugs were higher in the relapse group preoperatively and in the first 24 months and complete withdrawal was more frequent in the control group (68% vs. 51%). Regarding seizure frequency, most patients had mild seizure relapse (single relapse seizure or <1/month).

SIGNIFICANCE

In our predominantly lesional cohort, complete resection of the MRI lesion is the most important factor to maintain long-term seizure freedom. Two patterns of recurrence were identified: (1) incomplete resected lesions with seizure generation in proximity to the initial resection and (2) epileptogenic networks not detected preoperatively or evolving in the postoperative interval and manifesting with new clinical and diagnostic features.

Relative contribution of individual versus combined functional imaging studies in predicting seizure freedom in pediatric epilepsy surgery: an area under the curve analysis

OBJECTIVE

The goal of this study was to evaluate the predictive value and relative contribution of noninvasive presurgical functional imaging modalities based on the authors' institutional experience in pursuing seizure-free surgical outcomes in children with medically refractory epilepsy.

METHODS

This was a retrospective, single-institution, observational cohort study of pediatric patients who underwent evaluation and surgical treatment for medically refractory partial epilepsy between December 2003 and June 2016. During this interval, 108 children with medically refractory partial epilepsy underwent evaluation for localization and resective epilepsy surgery. Different noninvasive functional imaging modalities, including ictal SPECT, FDG-PET, and magnetoencephalography-magnetic source imaging, were utilized to augment a standardized paradigm (electroencephalography/semiology, MRI, and neuropsychology findings) for localization. Outcomes were evaluated at a minimum of 2 years (mean 7.5 years) utilizing area under the receiver operating characteristic curve analysis. Localizing modalities and other clinical covariates were examined in relation to long-term surgical outcomes.

RESULTS

There was variation in the contribution of each test, and no single presurgical workup modality could singularly and reliably predict a seizure-free outcome. However, concordance of presurgical modalities yielded a high predictive value. No difference in long-term outcomes between inconclusive (normal or diffusely abnormal) and abnormal focal MRI results were found. Long-term survival analyses revealed a statistically significant association between seizure freedom and patients with focal ictal EEG, early surgical intervention, and no history of generalized convulsions.

CONCLUSIONS

Comprehensive preoperative evaluation utilizing multiple noninvasive functional imaging modalities is not redundant and can improve pediatric epilepsy surgical outcomes.

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.

Focal cortical dysplasia: etiology, epileptogenesis, classification, clinical presentation, imaging, and management

BACKGROUND

Focal cortical dysplasia (FCD) is the most prevalent cause of intractable epilepsy in children. It was first described by Taylor et al. in 1971. In 2011, the International League against Epilepsy described an international consensus of classification for FCD. However, the exact mechanism causing this pathology remains unclear. The diagnosis and recognition of FCD increase with the advances in neuroradiology and electrophysiology.

FOCUS OF REVIEW

In this paper, we discuss the literature regarding management of FCD with a focus on etiology, pathophysiology, classification, clinical presentation, and imaging modalities. We will also discuss certain variables affecting surgical outcome of patients with FCD.

CONCLUSION

Based on our review findings, it is concluded that surgical management with complete resection of the lesion following preoperative localization of the epileptogenic zone in patients with FCD subtypes can provide a seizure-free outcome.

Localization of epileptic seizure focus by computerized analysis of fMRI recordings

By computerized analysis of cortical activity recorded via fMRI for pediatric epilepsy patients, we implement algorithmic localization of epileptic seizure focus within one of eight cortical lobes. Our innovative machine learning techniques involve intensive analysis of large matrices of mutual information coefficients between pairs of anatomically identified cortical regions. Drastic selection of pairs of regions with biologically significant inter-connectivity provides efficient inputs for our multi-layer perceptron (MLP) classifier. By imposing rigorous parameter parsimony to avoid overfitting, we construct a small-size MLP with very good percentages of successful classification.

Measure thrice, cut twice: On the benefit of reoperation for failed pediatric epilepsy surgery

OBJECTIVE

To determine whether clinical outcomes are improved after repeat surgery for medically refractory epilepsy in children.

METHODS

This is a single-center retrospective cohort analysis of all patients who received repeat resective surgery for ongoing seizures from 2000-2017. From a total of 251 consecutive individual epilepsy surgical patients for focal resection, 53 patients met study inclusion criteria and had adequate follow-up documented.

RESULTS

Median age of seizure-onset was 2.0-years-old (IQR 0.3-5.5 years). The median age at first epilepsy surgery was 6.3-years-old (IQR 2.9-9.2 years) and at second epilepsy surgery was 8.4-years-old (IQR 4.7-12.6 years). Overall, 53 % (n = 28) of this series achieved Engel Class I (seizure freedom); with improved seizure control (Engel Class I-II) in 83 % (n = 44) of the cohort. 64 % (n = 34) had one reoperation; 26 % (n = 14) had two; and 9% (n = 5) had three. Pathology: 58 % (n = 31) had focal cortical dysplasia; 13 % (n = 10) tumor; 9% (n = 5) encephalitis; 6% (n = 3) gliosis; 4% (n = 2) mesial temporal sclerosis; and 2% (n = 1) hemimegalencephaly. Tumor pathology was associated with increased chance (p = 0.01) for seizure freedom (90 % of tumor patients had Engel Class I outcome). MTS had worse outcome with both patients having ongoing seizures (Engel II-IV). There were 6 patients who developed post-operative hemiparesis; one was unplanned but resolved.

SIGNIFICANCE

Reoperation for pediatric epilepsy surgery can lead to seizure freedom in many cases and improved seizure control in most cases. Reoperation for brain tumor pathology is associated with a high rate of seizure freedom.

Seizure outcome of pediatric epilepsy surgery

Objective

This systematic review and meta-analyses assessed seizure outcome following pediatric epilepsy surgery.

Methods

MEDLINE, EMBASE, and Cochrane were searched for pediatric epilepsy surgery original research from 1990 to 2017. The outcome was seizure freedom at 12 months or longer follow-up. Using random-effects models, the effect sizes for controlled studies, uncontrolled studies on surgery locations (temporal lobe [TL], extratemporal lobe [ETL], or hemispheric surgery), pathologies, nonlesional epilepsy, and incomplete resection were estimated. Meta-regression assessed the relationship between age at surgery, age at seizure onset, and seizure outcome. Random-effects network meta-analysis was conducted for surgery locations.

Results

Two hundred fifty-eight studies were included. Surgery achieved higher seizure freedom than medical therapy (odds ratio [OR] = 6.49 [95% confidence interval [CI]: 2.87–14.70], p < 0.001). Seizure freedom declined over time after surgery, from 64.8% (95% CI: 51.2%–76.4%; p = 0.034) at 1 year, to 60.3% (95% CI: 52.9%–67.4%; p = 0.007) at 5 years, and to 39.7% (95% CI: 28.4%–52.2%, p = 0.106) at 10 years. Seizure freedom was (1) highest for hemispheric surgery, followed by TL and ETL surgery, and (2) highest for tumor and lower for malformations of cortical development. Seizure freedom was lower for nonlesional than lesional epilepsy (OR = 0.54 [95% CI: 0.34, 0.88], p = 0.013) and incomplete than complete resection (OR = 0.13 [95% CI: 0.08, 0.21], p < 0.001). Age at surgery and age at seizure onset were associated with seizure freedom for mixed pathologies and surgery locations and TL surgery.

Conclusion

Epilepsy surgery was more effective than medical therapy to control seizures. Understanding seizure outcomes of different surgery locations, pathologies, nonlesional epilepsy, and incomplete resection will assist with presurgical counseling.

An Initial Cost-Effectiveness Analysis of Magnetic Resonance-Guided Laser Interstitial Thermal Therapy in Pediatric Epilepsy Surgery

INTRODUCTION

Magnetic resonance-guided laser interstitial thermal therapy (MRgLITT) is a new technology that provides a clinically efficacious and minimally invasive alternative to conventional microsurgical resection. However, little data exist on how costs compare to traditional open surgery. The goal of this paper is to investigate the cost-effectiveness of MRgLITT in the treatment of pediatric epilepsy.

METHODS

We retrospectively analyzed the medical records of pediatric patients who underwent MRgLITT via the Visualase® thermal therapy system (Medtronic, Inc., Minneapolis, MN, USA) between December 2013 and September 2017. Direct costs associated with preoperative, operative, and follow-up care were extracted. Benefit was calculated in quality-adjusted life years (QALYs), and the cost-effectiveness was derived from the discounted total direct costs over QALY. Sensitivity analysis on 4 variables was utilized to assess the validity of our results.

RESULTS

Twelve consecutive pediatric patients with medically refractory epilepsy underwent MRgLITT procedures. At the last postoperative follow-up, 8 patients were seizure free (Engel I, 66.7%), 2 demonstrated significant improvement (Engel II, 16.7%), and 2 patients showed worthwhile improvement (Engel III, 16.7%). The average cumulative discounted QALY was 2.11 over the lifetime of a patient. Adjusting for inflation, MRgLITT procedures had a cost-effectiveness of USD 22,211 per QALY. Our sensitivity analysis of cost variables is robust and supports the procedure to be cost--effective.

CONCLUSION

Our data suggests that MRgLITT may be a cost-effective alternative to traditional surgical resection in pediatric epilepsy surgery.

Long-term employment outcomes after epilepsy surgery in childhood

Objective

To analyze long-term employment outcomes in a population-based cohort of adults who underwent epilepsy surgery in childhood or adolescence and to compare the results to general population reference data.

Methods

Prospective data on epilepsy surgery procedures performed on patients <19 years of age between 1995 and 2012 were extracted from the Swedish National Epilepsy Surgery Register. Five-, 10-, 15- and 20-year follow-up data were analyzed. Patients aged ≥19 years at follow-up were eligible for inclusion. Educational attainment and employment status were analyzed in relation to seizure outcome. Education and employment outcomes of seizure-free patients with a preoperative IQ of ≥70 were compared to general population reference data.

Results

A total of 203 patients were included. The mean age at surgery was 13.6 years and 66% had IQ ≥70. Of these, a majority had attained at least high school education 5 years after surgery. Employment rates were 44%, 69%, 71%, and 77% at the 5-, 10-, 15-, and 20-year follow-ups, respectively. Seizure-free patients were significantly more likely to work full-time. Educational attainment and rates of full-time employment of seizure-free patients were similar to the general population. A majority of patients with IQ <70 had attended special education and were reliant on social benefits.

Conclusion

Long-term overall employment rates were higher compared to most previous studies on surgery in adults. Seizure-free patients with a preoperative IQ ≥70 showed rates of full-time employment similar to the general population. Further research is needed to determine whether this also applies for occupational complexity and wages.

Parents' view of the cognitive outcome one year after pediatric epilepsy surgery

OBJECTIVES

The cognitive outcome of pediatric epilepsy surgery has mainly been examined on the basis of standardized tests. Here, we analyzed the outcome in six cognitive domains from the parents' view.

METHODS

Included were consecutive surgical pediatric patients whose parents filled-in a comprehensive questionnaire on cognitive problems in children and adolescents (Kognitive Probleme bei Kindern und Jugendlichen (KOPKIJ); Gleissner et al. 2006) at the preoperative baseline (T1) as well as twelve months thereafter (T2). All children also underwent standard neuropsychological assessments at T1 and T2.

RESULTS

Parents of 96 patients provided pre- and postoperative KOPKIJ data. Overall, 80% of the children became seizure-free at the follow-up. Group means indicated a strong positive effect of time on KOPKIJ and neuropsychological performance. We found postoperative improvements in five out of six cognitive domains (language, memory, executive functions, attention, school; unchanged: visuospatial abilities). Individually, improvements were twice as likely as declines. However, 33 patients (35%) experienced significant decline in at least one cognitive domain. Later onset of epilepsy resulted in better performance but had no effect on change scores. Seizure-free status, lower antiseizure drug load, and stronger drug reduction after surgery contributed to postoperative cognitive improvements as perceived by the parents; no other effects of clinical factors were obtained (e.g., localization/lateralization). Despite their similar outcome patterns, change scores as derived from parental ratings and neuropsychological assessment were not correlated.

CONCLUSIONS

Parents acknowledged the overall positive neurocognitive development after pediatric epilepsy surgery as previously shown by standardized tests. Seizure freedom and lower antiseizure drug load contributed to the beneficial cognitive outcome. Even if cognitive improvements outweighed declines, a risk for cognitive decline with impact on everyday functioning does exist.

Refractory seizures: Prediction of outcome of surgical intervention based on results from PET-CT, PET-MRI and electroencephaolography

PURPOSE

The purpose of this article is to evaluate the effectiveness of fluorodeoxyglucose (FDG) positron emission tomography (PET)-computed tomography (CT) and PET-magnetic resonance imaging (MRI) with scalp and intracranial electroencephalogram (EEG) in predicting surgical outcomes in patients with refractory seizures.

METHODS

Patients who underwent PET-CT and MRI fusion, scalp and intracranial EEG, and subsequent surgical intervention were retrospectively included. PET-CT were fused with MRI and interpreted by an experienced blinded reader. An area of hypometabolism on PET was identified as the location of the epileptic focus. The site of seizure focus was correlated with scalp and intracranial EEG findings. Surgical outcomes were evaluated. Thirty-six patients were included; all had presurgical PET-CT, scalp EEG, and PET-MRI fusion, and 28 of these patients had intracranial EEGs.

RESULTS

PET-CT showed concordance of epileptic foci with scalp EEG in 7/36 patients (19%) and with intracranial EEG in 9/28 patients (32%). PET-MRI was concordant with scalp EEG in 6/36 patients (17%) and with intracranial EEG in 8/28 patients (29%). All patients with concordance of epileptic foci between PET-CT and PET-MRI and scalp EEG had improvement or resolution of seizures postintervention, and 89% of patients had concordance between intracranial EEG and PET studies. However, 45% of patients with discordant PET-CT and scalp EEG, 37% with discordance PET-CT and intracranial EEG, 43% with discordant PET-MRI and scalp EEG, and 35% of patients with discordant PET-MRI and intracranial EEG did not improve postsurgically.

CONCLUSION

Concordance of epileptic foci localization between PET imaging and EEG yields favorable postoperative outcome in nearly all patients, whereas discordance has an equal probability of favorable vs unfavorable outcomes.

Synthetic aperture magnetometry and excess kurtosis mapping of Magnetoencephalography (MEG) is predictive of epilepsy surgical outcome in a large pediatric cohort

OBJECTIVE

Resective surgery is the most effective treatment option for patients with refractory epilepsy; however identification of patients who will benefit from epilepsy surgery remains challenging. Synthetic aperture magnetometry and excess kurtosis mapping (SAM(g2)) of magnetoencephalography (MEG) is a non-invasive tool that warrants further examination in the pediatric epilepsy population. Here, we examined the utility of MEG with SAM(g2) to determine if MEG epileptiform foci correlates with surgical outcome and to develop a predictive model incorporating MEG information to best assess likelihood of seizure improvement/freedom from resective surgery.

METHODS

564 subjects who had MEG at the Children's Hospital of Philadelphia between 2010-2015 were screened. Clinical epilepsy history and prior electrographic records were extracted and reviewed and correlated with MEG findings. MEG assessments were made by both a neurologist and neuroradiologist. Predictive models were developed to assess the utility of MEG in determining Engel class at one year and five years after resective epilepsy surgery.

RESULTS

The number of MEG spike foci was highly associated with Engel class outcome at both one year and five years; however, using MEG data in isolation was not significantly predictive of 5 year surgical outcome. When combined with clinical factors; scalp EEG (single ictal onset zone), MRI (lesional or not), age and sex in a logistic regression model MEG foci was significant for Engel class outcome at both 1 year (p = 0.03) and 5 years (0.02). The percent correctly classified for Engel class at one year was 78.43% and the positive predictive value was 71.43.

SIGNIFICANCE

MEG using SAM(g2) analysis in an important non-invasive tool in the identification of those patients who will benefit most from surgery. Integrating MEG data analysis into pre-surgical evaluation can help to predict epilepsy outcome after resective surgery in the pediatric population if utilized with skilled interpretation.

When Epilepsy Grows Up…

Neurocognition in Childhood Epilepsy: Impact on Mortality and Complete Seizure Remission 50 Years Later

Sillanpää M, Saarinen MM, Karrasch M, Schmidt D, Hermann BP. Epilepsia. 2019;60(1):131-138. doi:10.1111/epi.14606. Epub 2018 Nov 22.

Objective:

To study associations of the severity of impairment in childhood neurocognition (NC) with long-term mortality and complete seizure remission.

Methods:

A population-based cohort of 245 subjects with childhood-onset epilepsy was followed up for 50 years (median = 45, range = 2-50). Childhood NC before age 18 years was assessed as a combination of formal intelligence quotient scores and functional criteria (school achievement, working history, and psychoneurological development). Impaired NC was categorized with respect to definitions of intellectual functioning in International Classification of Diseases, Tenth Revision (R41.83, F70-F73). The outcome variables, defined as all-cause mortality and 10-year terminal remission with the 5 past years off medication (10YTR), were analyzed with Cox regression models.

Results:

Of the 245 subjects, 119 (49%) had normal childhood NC, whereas 126 (51%) had various degrees of neurocognitive impairment. During the 50-year observation period, 71 (29%) of the subjects died, 13% of those with normal and 44% of those with impaired NC. The hazard of death increased gradually in line with more impaired cognition, reaching significance in moderate, severe, and profound impairment versus normal NC (hazard ratio [Bonferroni corrected 95% confidence interval] = 3.3 [1.2-9.2], 4.2 [1.2-14.2], and 5.5 [2.4-12.3], respectively). The chance for 10YTR was highest among subjects with normal NC (61%), whereas none of those with profound impairment reached 10YTR. In the intermediate categories, the chance was, however, not directly related to the increasing severity of impairment.

Significance:

The severity of neurocognitive impairment during childhood shows a parallel increase in the risk of death. In comparison with normal NC, subjects with lower childhood NC are less likely to enter seizure remission. However, normal NC does not guarantee complete remission or prevent premature death in some individuals with childhood-onset epilepsy.

Social outcomes for adults with a history of childhood-onset epilepsy: A systematic review and meta-analysis

OBJECTIVES

This review aimed to describe social outcomes in adulthood for people with a history of childhood-onset epilepsy and identify factors associated with these outcomes; focused on educational attainment, employment, income/financial status, independence/living arrangement, romantic relationships, parenthood, and friendships.

METHODS

A comprehensive search of MEDLINE, EMBASE, and PsycINFO was conducted, as well as forward and backward citation tracking. A total of 45 articles met inclusion criteria. Random effects meta-analyses were conducted, and subgroup analyses evaluated outcomes for people with epilepsy (PWE) with good prognosis (e.g., normal intelligence, 'epilepsy-only') and poor prognosis (e.g., intellectual disability, Dravet syndrome), and those who underwent epilepsy surgery in childhood.

RESULTS

Among all PWE, 73% (95% confidence interval [CI]: 64-82%) completed secondary school education, 63% (95%CI: 56-70%) were employed; 74% (95%CI: 68-81%) did not receive governmental financial assistance; 32% (95%CI: 25-39%) were in romantic relationships; 34% (95%CI: 24-45%) lived independently; 21% (95%CI:12-33%) had children, and 79% (95%CI: 71-87%) had close friend(s). People with epilepsy often fared worse relative to healthy controls. Among PWE with a good prognosis, a comparable number of studies reported similar/better outcomes relative to controls as reported poorer outcomes. The most consistent predictor of poorer outcomes was the presence of cognitive problems; results of studies evaluating seizure control were equivocal.

CONCLUSION

People with epilepsy with a good prognosis may show similar social outcomes as controls, though robust conclusions are difficult to make given the extant literature. Seizure control does not guarantee better outcomes. There is a need for more studies evaluating prognostic factors and studies with control groups to facilitate appropriate comparisons.

Surgery in patients with childhood-onset epilepsy: analysis of complications and predictive risk factors for a severely complicated course

OBJECT

To compare the occurrence of surgery-related complications in patients with childhood-onset focal epilepsy operated on in the paediatric or in the adult age. To investigate risk factors for surgery-related complications in the whole cohort, with special attention to age at surgery and severe morbidity.

METHODS

A cohort of 1282 patients operated on for childhood-onset focal epilepsy was retrospectively analysed. Occurrence of surgery-related complications, including a severely complicated course (SCC: surgical complication requiring reoperation and/or permanent neurological deficit and/or death), was compared between patients operated on in the paediatric age (<16 year-old; 452 cases) and, respectively, in adulthood (≥16 year-old; 830 cases). The whole cohort of patients was also evaluated for risk factors for a SCC.

RESULTS

At last contact (median follow-up 98 months), 74.5% of patients were in Engel's class I (78.0% of children and 73.0% of adults). One hundred patients (7.8%) presented a SCC (6.4% for children and 8.6% for adult patients). Postoperative intracranial haemorrhages occurred more frequently in adult cases. At multivariate analysis, increasing age at operation, multilobar surgery, resections in the rolandic/perirolandic and in insulo-opercular regions were independent risk factors for a SCC.

CONCLUSIONS

Surgery for childhood-onset focal epilepsy provides excellent results on seizures and an acceptable safety profile at any age. Nevertheless, our results suggest that increasing age at surgery is associated with an increase in odds of developing severe surgery-related complications. These findings support the recommendation that children with drug-resistant, symptomatic (or presumed symptomatic) focal epilepsy should be referred for a surgical evaluation as early as possible after seizure onset.

Quality of Life After Epilepsy Surgery in Children: A Systematic Review and Meta-Analysis

BACKGROUND

Pediatric epilepsy surgery is a treatment modality appropriate for select patients with debilitating medication-resistant seizures. Previous publications have studied seizure freedom as the main outcome of epilepsy surgery. However, there has been no systematic assessment of the postoperative life quality for these children.

OBJECTIVE

To estimate the quality of life (QOL) long-term outcomes after surgery for intractable epilepsy in pediatric patients.

METHODS

A systematic search of the PubMed and Cochrane databases was performed. Studies reporting questionnaire-assessed QOL at least 12 months postoperatively were included. QOL means and standard deviations were compared between surgically and medically managed patients, between the preoperative and postoperative state of each patient, and were further stratified into patients achieving seizure freedom, and those who did not. Meta-analysis was performed using fixed effects models for weighted mean differences (WMD), 95% confidence intervals (CI) and sensitivity analyses. Funnel plots and Begg's tests were utilized to detect publication bias.

RESULTS

The search yielded 18 retrospective studies, reporting 890 surgical patients. Following epilepsy surgery, children had significant QOL improvement compared to their preoperative state (WMD: 16.71, 95% CI: 12.19-21.22, P < .001) and better QOL than matched medically treated controls (WMD: 12.42, 95% CI: 6.25-18.58, P < .001). Patients achieving total seizure freedom after surgery had significant postoperative QOL improvement (WMD: 16.12, 95% CI: 7.98-24.25, P < .001), but patients not achieving seizure freedom did not achieve statistical significance (P = .79).

CONCLUSION

Epilepsy surgery can effectively improve QOL in children with medication-resistant seizures, through seizure freedom, which was associated with the greatest improvement in life quality.

Seizure outcome in pediatric medically refractory temporal lobe epilepsy surgery: selective amygdalohippocampectomy versus anterior temporal lobectomy

OBJECTIVE The aim of this study was to investigate long-term seizure outcome, rate of reoperation, and postoperative neuropsychological performance following selective amygdalohippocampectomy (SelAH) or anterior temporal lobectomy (ATL) in pediatric patients with medically refractory temporal lobe epilepsy (TLE). METHODS The authors performed a retrospective review of cases of medically refractory pediatric TLE treated initially with either SelAH or ATL. Standardized pre- and postoperative evaluation included seizure charting, surface and long-term video-electroencephalography, 1.5-T MRI, and neuropsychological testing. RESULTS A total of 79 patients treated initially with SelAH (n = 18) or ATL (n = 61) were included in this study, with a mean follow-up of 5.3 ± 4 years (range 1-16 years). The patients' average age at initial surgery was 10.6 ± 5 years, with an average surgical delay of 5.7 ± 4 years between seizure onset and surgery. Seizure freedom (Engel I) following the initial operation was significantly more likely following ATL (47/61, 77%) than SelAH (8/18, 44%; p = 0.017, Fisher's exact test). There was no statistically significant difference in the proportion of patients with postoperative neuropsychological deficits following SelAH (8/18, 44%) or ATL (21/61, 34%). However, reoperation was significantly more likely following SelAH (8/18, 44%) than after ATL (7/61, 11%; p = 0.004) and was more likely to result in Engel I outcome for ATL after failed SelAH (7/8, 88%) than for posterior extension after failed ATL (1/7, 14%; p = 0.01). Reoperation was well tolerated without significant neuropsychological deterioration. Ultimately, including 15 reoperations, 58 of 79 (73%) patients were free from disabling seizures at the most recent follow-up. CONCLUSIONS SelAH among pediatric patients with medically refractory unilateral TLE yields significantly worse rates of seizure control compared with ATL. Reoperation is significantly more likely following SelAH, is not associated with incremental neuropsychological deterioration, and frequently results in freedom from disabling seizures. These results are significant in that they argue against using SelAH for pediatric TLE surgery.

Children with autism spectrum disorders and drug-resistant epilepsy can benefit from epilepsy surgery

OBJECTIVE

The objective of this research was to evaluate a cohort of children with both autism spectrum disorder (ASD) and drug-resistant epilepsy (DRE) after epilepsy surgery to determine predictors of best outcome.

METHODS

Retrospective chart review was done for 29 children ages 2 to 18 years with ASD and DRE who had neurosurgical intervention for seizure management over 15 years at one institution. All subjects had at least 1 year of follow-up. Data abstraction included demographic information, seizure diagnosis, treatment, investigations, surgical intervention, neuropsychological assessment, and outcome. Statistical analysis software (SAS) was used for statistical analysis. Engel classification was used to assess seizure outcome.

RESULTS

Fifteen subjects had resective surgery. Fourteen had palliative surgery with vagal nerve stimulator (VNS) insertion (13) and corpus callosotomy (1). Of the 29 subjects, 35% had class I outcome (all in the resective group). When combining all subjects (resective and palliative), 66% of subjects benefited with class I-III outcomes. In the total cohort, age at time of surgery was significant, with class I outcome more frequently seen in the younger age group when compared with classes II-IV (p = 0.01).

CONCLUSION

A subset of children with ASD can benefit from resective surgery, and for those who are not candidates, a VNS can offer significant improvements in seizure control.

Risk factors for surgical site infection after intracranial electroencephalography monitoring for epilepsy in the pediatric population

OBJECTIVE Intracranial electroencephalography (iEEG) monitoring is an important method of identifying the seizure focus in patients with medically refractory epilepsy. While previous studies have demonstrated low rates of surgical complications, reported rates of surgical site infection (SSI) are highly variable. To date, no studies have specifically evaluated the patient or operative risk factors contributing to SSI. The goals of this study were to examine the rate of SSI after iEEG monitoring for epilepsy workup in pediatric patients and to determine the variables that might contribute to the development of SSI. METHODS A retrospective analysis of hospital charts at the Hospital for Sick Children was performed for all patients who had undergone iEEG monitoring between 2000 and 2016. Univariate and multivariate analyses were performed to look for statistically significant variables in relation to SSI. RESULTS Among 199 patients eligible for analysis, 8 (4.0%) developed SSIs within a period ranging from 21 to 51 days postoperatively. Univariate analysis yielded 4 factors related to SSI: number of people present in the operating room on electrode insertion (p = 0.02), length of insertion surgery (p = 0.04), previous operation at the same surgical site (p = 0.04), and number of depth electrodes inserted (p = 0.01). Multivariate analysis revealed that both the number of people present during the implant operation (OR 0.08, 95% CI 0.01-0.70) and the number of depth electrodes inserted (OR 3.52, 95% CI 1.44-8.59) independently contributed to SSI. CONCLUSIONS This is the largest case series and the first comprehensive review of both patient and operative risk factors in the development of SSI from iEEG monitoring in a pediatric population. The authors' institution had a lower rate of infection than those in most other studies, which could be explained by their protocol of administering intravenous antibiotics perioperatively and post-implant removal antibiotics for 14 days. The authors found a correlation between SSI and the number of people present during the implant operation, as well as the number of depth electrodes; both may contribute to breaks in sterility.