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Objective: We describe a multicenter experience with vagus nerve stimulator implantation in pediatric patients with drug-resistant epilepsy. Our goal was to assess vagus nerve stimulation efficacy and identify potential predictors of favorable outcome. Methods: This is a retrospective study. Inclusion criteria: ≤18 years at time of vagus nerve stimulator implantation, at least 1 year of follow-up. All patients were previously found to be unsuitable for an excisional procedure. Favorable clinical outcome and effective vagus nerve stimulation therapy were defined as seizure reduction >50%. Outcome data were reviewed at 1, 2, 3, and 5 years after vagus nerve stimulator implantation. Fisher exact test and multiple logistic regression analysis were employed. Results: Eighty-nine patients met inclusion criteria. Responder rate (seizure frequency reduction >50%) at 1-year follow-up was 25.8% (4.5% seizure-free). At last follow-up, 31.5% had a favorable outcome and 5.2% were seizure free. The only factor significantly predicting favorable outcome was time to vagus nerve stimulator implantation, with the best outcome achieved when vagus nerve stimulator implantation was performed within 3 years of seizure onset. Implantation between 3 and 5 years after epilepsy onset correlated with better long-term seizure freedom (13.3% at T5). Overall, 65.2% of patients evidenced improved quality of life at last follow-up. However, 12.4% had adverse events, but most were mild and disappeared after 3-4 months. Conclusions: Early vagus nerve stimulator implantation within 5 years of seizure onset was the only predictor of favorable clinical outcome in pediatric patients. Improved quality of life and a low incidence of significant adverse events were observed.

Objective To describe the characteristics of pediatric intensive care neurologists and their practice in the United States and Canada. Methods We performed a survey-based study of child neurologists who self-identify as ‘intensive care neurologists’. The survey included questions about demographics, training, pediatric neurocritical care service and job structure, teaching, academics, challenges, and views on the future of pediatric neurocritical care. Results We analyzed 55 surveys. Most respondents were 31-50 years of age with ≤10 years of practice experience. Fifty-four percent identified as female. Most completed subspecialty training after child neurology residency. The majority practice at highly resourced centers with >45 intensive care unit beds. Respondents cover a variety of inpatient (critical and noncritical care) services, at times simultaneously, for a median of 19.5 weeks/y and work >70 hours/wk when on service for pediatric neurocritical care. The top 3 challenges reported were competing demands for time, excess volume, and communication with critical care medicine. Top priorities for the “ideal pediatric neurocritical care service” were attendings with training in pediatric neurocritical care or a related field and joint rounding with critical care medicine. Conclusion We report a survey-based analysis of the demographics and scope of practice of pediatric critical care neurologists. We highlight challenges faced and provide a framework for the further development of this rapidly growing field.

Although certain clinical, electroencephalographic (EEG), magnetic resonance imaging (MRI), and pathologic findings in adults with intractable temporal lobe epilepsy predict seizure outcome following temporal lobectomy, predictors of seizure outcome have not been studied systematically in pediatric temporal lobectomy series. We retrospectively analyzed preoperative clinical, EEG, and neuroimaging findings with reference to seizure outcome (seizure free or non-seizure free) in 33 children (mean age, 9.3 years) who underwent tailored temporal lobe resections for intractable temporal lobe epilepsy. Trends were apparent with (1) younger age at seizure onset, younger age at surgery, shorter duration of epilepsy, localized unilateral temporal lesions on MRI, and right-sided surgery more frequently associated with a seizure-free outcome, and (2) significant prior history, daily preoperative seizures, generalized motor seizures, mental retardation, and localized unilateral temporal epileptiform EEG activity more frequently associated with a non-seizure-free outcome. However, none of these findings, alone or in combination, correlated with postoperative seizure status at a statistically significant level. Submitting the four variables generally considered to be most predictive of favorable outcome (ie, normal intelligence, unilateral ictal and interictal EEG discharges, and focal temporal MRI lesion) to a multiple-cutoff procedure did not predict seizure freedom. Our data indicate that predictors of outcome of temporal lobectomy in adults may not apply in children, perhaps due to inherent neurobiologic differences in the etiology and expression of temporal lobe epilepsy, and should therefore not be used as sole determinants of surgical candidacy in children. (J Child Neurol 1996;11:445-450).

This study investigated differences in propositional language organization in children with developmental and acquired brain lesions. We evaluated 30 right-handed subjects with intractable epilepsy due to either focal cortical dysplasia or hippocampal sclerosis with neuropsychological testing and functional MRI prior to epilepsy surgery. Atypical activations were seen in both prenatal and early postnatal lesions, but the contribution of specific histopathological substrate was minimal. Atypical organization of both temporal and frontal language areas also correlated inversely with receptive vocabulary scores. The data demonstrated a greater propensity toward atypical activation patterns for receptive than expressive networks, particularly when lesions were located in the dominant temporal lobe. Atypical language organization was not correlated with seizure-related factors such as age at onset or duration of epilepsy. The patterns of atypical language activation support prior studies implicating proximity of pathology to eloquent cortex in the dominant hemisphere as the primary determinant of functional reorganization.

The objective of this study was to determine the value of continuous-display four-channel electroencephalographic (EEG) monitoring to distinguish epileptic from nonepileptic paroxysmal motor events. Five full-term neonates with paroxysmal motor events were included in the study. Nurses were instructed to print contiguous pages of the continuous-display four-channel EEG monitoring and to activate the event marker on the simultaneously conducted continuous video-EEG telemetry unit during each paroxysmal motor event. The printouts from the continuous-display four-channel EEG monitoring were interpreted and compared with the corresponding segments of continuous video-EEG telemetry. Thirty paroxysmal motor events were captured. Sixteen paroxysmal motor events were epileptic, and 14 were nonepileptic. The interpretation of the printouts of the continuous four-channel EEG monitoring concurred with an independent interpretation of the corresponding video-EEG telemetry segments in all of the events. Continuous-display four-channel EEG monitoring is a valuable tool in the evaluation of neonates with paroxysmal motor events since it reliably distinguishes epileptic and nonepileptic events. (J Child Neurol 2001;16:625-628).

We report a series of nine children with multiple daily seizures since infancy who underwent functional hemispherectomy that included en bloc resection of the hippocampus and the temporal neocortex. In all cases, the hippocampi were normal by conventional histology despite the fact that these patients had suffered from recurrent seizures over a long period of time. This observation suggests that extremely frequent seizures in childhood are not invariably associated with the development of hippocampal sclerosis. (J Child Neurol 2001;16:562-564).

Children with well-localized medically resistant seizures are often referred for surgical therapy. In young children, at least three maturational issues play a significant role in the selection process and long-term outcome. First, the early years are a time of exceptionally rapid brain development leading to dynamic changes in the electroencephalogram and the clinical expression of seizures. Many early-onset seizure presentations are also associated with catastrophic outcomes, developmental arrest, or regression. Second, the immature limbic system may be vulnerable to stresses operating in early life, although the consequences may not become apparent for many years. Third, in comparison to the adult, the child's nervous system typically exhibits superior functional recovery after lesioning, but the process of sparing and recovery is often incomplete. An understanding of how these neurobiologic factors influence developmental outcome will ultimately lead to greater selectivity of candidates for early surgery and to improved long-term prognosis.

Surgical resection for localization-related epilepsy has recently become a generally accepted treatment in children. Evidence of the poor outcome in natural history studies of temporal lobe epilepsy in childhood initiated consideration of surgical intervention. Subsequent favorable outcome following surgery was encouraging. A number of variables differentiate adults with focal seizures from children. Evolving biologic factors modify the clinical and electroencephalographic expression of seizures in childhood. The pathologic substrate is different, and there is a higher incidence of extratemporal epilepsy. Chronic seizures beginning under age 2 years rarely remit, especially when associated with a demonstrable structural lesion. Behavioral consequences of chronic seizures are significant and become a major problem by adolescence if seizures are not controlled. Early surgery results in superior functional outcome, although subtle deficits persist postoperatively. Surgical outcome is as favorable as in adults with improvements in behavioral status and socialization. Abundant data exist to more adequately assess the benefits and risks of surgery in children so that intervention is not deferred longer than it needs to be. (J Child Neurol 1994;9(Suppl):2S36-2S41)

Children with well-localized medically resistant seizures are often referred for surgical therapy. In young children, at least three maturational issues playa significant role in the selection process and long-term outcome. First, the early years are a time of exceptionally rapid brain development leading to dynamic changes in the electroencephalogram and the clinical expression of seizures. Many early-onset seizure presentations are also associated with catastrophic outcomes, developmental arrest, or regression. Second, the immature limbic system may be vulnerable to stresses operating in early life, although the consequences may not become apparent for many years. Third, in comparison to the adult, the child's nervous system typically exhibits superior functional recovery after lesioning, but the process of sparing and recovery is often incomplete. An understanding of how these neurobiologic factors influence developmental outcome will ultimately lead to greater selectivity of candidates for early surgery and to improved long-term prognosis. (J Child Neurol 1994;9(Suppl):2S42-2S49).

Noninvasive assessment of children with chronic epilepsy is often imprecise and localization of seizure foci requires intracranial electroencephalographic monitoring. Subdural electrodes provide coverage of large areas of neocortex and are ideally suited for evaluating children with intractable epilepsy and to functionally map critical cortex. This report discusses the role of subdural electroencephalography in the evaluation of childhood epilepsy. (J Child Neurol 1994; 9(Suppl):2S61-2S66).