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Disparities in epilepsy treatment have previously been reported. In the current study, we examine the role of socioeconomic status, health insurance, place of residence, and sociodemographic characteristics in past-year visit to a neurology or epilepsy provider and current use of antiseizure medications. Multiple years of data were compiled from the National Health Interview Surveys, Sample Adult Epilepsy Modules. The sample (n = 1655) included individuals 18 years and older who have been told by a doctor to have epilepsy or seizures. Independent variables included number of seizures in the past year, health insurance, poverty status, education, region, race/ethnicity, foreign-born status, age, and sex/gender. Two sets of weighted hierarchical logistic regression models were estimated predicting past-year epilepsy visit and current medication use. Accounting for recent seizure activity and other factors, uninsured and people residing outside of the Northeast were less likely to see an epilepsy provider, and people living in poverty were less likely to use medications, relative to their comparison groups. However, no racial/ethnic and nativity-based differences in specialty service or medication use were observed. Further research, including longitudinal studies of care trajectories and outcomes, are warranted to better understand healthcare needs of people with epilepsy, in particular treatment-resistant seizures, and to develop appropriate interventions at the policy, public health, and health system levels.

OBJECTIVEThe 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.METHODSThis 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.RESULTSThere 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.CONCLUSIONSComprehensive preoperative evaluation utilizing multiple noninvasive functional imaging modalities is not redundant and can improve pediatric epilepsy surgical outcomes.

Objective For patients with nonlesional refractory focal epilepsy (NLRFE), localization of the epileptogenic zone is more arduous, and intracranial electroencephalography (EEG) (icEEG) is frequently required. Planning for icEEG is dependent on combined data from multiple noninvasive modalities. We report the negative impact of lack of integration of magnetoencephalography (MEG) in the presurgical workup in NLRFE. Methods Observational MEG case series involving 31 consecutive patients with NLRFE in an academic epilepsy center. For various reasons, MEG data were not analyzed in a timely manner to be included in the decision-making process. The presumed impact of MEG was assessed retrospectively. Results Magnetoencephalography would have changed the initial management in 21/31 (68%) had MEG results been available by reducing the number of intracranial electrodes, modifying their position, allowing for direct surgery, canceling the intracranial study, or providing enough evidence to justify one. Good surgical outcome was achieved in 11 out of 17 patients who proceeded to epilepsy surgery. Nine out of eleven had MEG clusters corresponding to the resection area, and MEG findings would have allowed for direct surgery (avoiding icEEG) in 2/11. Six patients had poor outcome including three patients where MEG would have significantly changed the outcome by modifying the resection margin. Magnetoencephalography provided superior information in 3 patients where inadequate coverage precluded accurate mapping of the epileptogenic zone. Conclusion In this single center retrospective study, MEG would have changed patient management, icEEG planning, and surgical outcome in a significant percentage of patients with NLRFE and should be considered in the presurgical workup in those patients.

Background Orbitofrontal epilepsy (OFE) is less known and is poorly characterized in comparison with temporal lobe epilepsy, partly because it is rare and possibly because it is unrecognized and therefore underestimated. Objective This paper aimed to better characterize seizure semiology, presurgical findings, and surgical outcomes in patients with OFE. Methods We retrospectively reviewed all confidently established OFE cases from six Canadian epilepsy monitoring units between 1988 and 2014, and in the literature between 1972 and 2017. Inclusion criteria were identification of an epileptogenic lesion localized in the OFC or if the patient was seizure-free after surgical removal of the OFC in nonlesional cases. Results Sixteen cases were identified from our databases. Fifty percent had predominantly sleep-related seizures; 56% had no aura (the remaining had nonspecific or vegetative auras), and 62.5% featured hypermotor (mostly hyperkinetic) behaviors. Interictal epileptiform discharges over frontal and temporal derivations always allowed lateralization. Magnetic resonance imaging (MRI) identified an orbitofrontal lesion in 8/16, positron emission tomography (PET) identified a hypometabolism extending outside the orbital cortex in 4/9, ictal single-photon emission computed tomography (SPECT) identified an orbital hyperperfusion in 1/5, magnetoencephalography (MEG) identified lateral orbital sources in 2/4, and intracranial electroencephalography (EEG) identified an orbitofrontal onset in 9/10. Fourteen patients underwent surgery, all reaching a favorable outcome (71.4% Engel 1; 28.6% Engel 2; mean FU = 5.6 years). Pre- and postoperative neuropsychological assessments revealed heterogeneous findings. Our review of literature identified 71 possible cases of OFE, 32 with confident focus localization. Extracted data from these cumulated cases supported observations made from our case series. Conclusions Orbitofrontal epilepsy should be suspected with sleep-related, hyperkinetic seizures with no specific aura, and frontotemporal interictal discharges. Several patients have nonmotor seizures with or without auras which may resemble temporal lobe seizures. Postoperative seizure outcome was favorable, but there is inherent bias as we only included patients with a seizure-free outcome if the MRI was negative. A larger study is required to address identified gaps in knowledge such as identifying discriminative features between medial and lateral OFE, evaluating the value of more recent diagnostic tools, and assessing the neuropsychological outcome of orbital epilepsy surgery.

Background Gelastic seizures (GS) are classically observed with hypothalamic hamartomas but they can also be associated with cortical epileptogenic foci. Objective To study the different cortical localizations associated with GS. Methods We reviewed the data from all patients with cortical GS investigated in our epilepsy unit from 1974 to 2012 and in the literature from 1956 to 2013. Results Sixteen cases were identified in our database and 77 in the literature. Investigations provided confident focus localization in 9 and 18, respectively. In our series, the identified foci were located in the mesial temporal structures (2 left, 1 right), lateral temporal cortex (1 right), superior frontal gyrus (1 left), and operculoinsular region [3 right (orbitofrontal or frontal operculum extending into the anterior insula) and 1 left (frontal operculum extending into the anterior insula)]. In the literature, the identified foci (13 right/5 left) were located in the temporal lobe of 4 (1 right inferior, 1 right medial and inferior, 1 right posterior middle, inferior extending posteriorly to the lingual gyrus, and 1 left middle, inferior, and medial), in the frontal lobe of 12 [10 (6 right/4 left) medial (i.e., superior, medial frontal, and/or anterior cingulate gyri), 1 lateral (right anterior inferior frontal gyrus), and 1 right medioposterior orbitofrontal cortex] and in the parietal lobe of 2 (1 left superior parietal lobule and 1 right parietal operculum) patients. Conclusion Ictal laughter is a poorly lateralizing and localizing feature as it may be encountered in patients with a focus in the left or right frontal, temporal, parietal, or insular lobe.

Focal cortical dysplasia is a common cortical malformation and an important cause of epilepsy. There is evidence for shared molecular mechanisms underlying cortical dysplasia, ganglioglioma, hemimegalencephaly, and dysembryoplastic neuroepithelial tumor. However, there are no familial reports of typical cortical dysplasia or co-occurrence of cortical dysplasia and related lesions within the same pedigree. We report the clinical, imaging, and histologic features of six pedigrees with familial cortical dysplasia and related lesions. Twelve patients from six pedigrees were ascertained from pediatric and adult epilepsy centers, eleven of whom underwent epilepsy surgery. Pedigree data, clinical information, neuroimaging findings, and histopathologic features are presented. The families comprise brothers with focal cortical dysplasia, a male and his sister with focal cortical dysplasia, a female with focal cortical dysplasia and her brother with hemimegalencephaly, a female with focal cortical dysplasia and her female first cousin with ganglioglioma, a female with focal cortical dysplasia and her male cousin with dysembryoplastic neuroepithelial tumor, and a female and her nephew with focal cortical dysplasia. This series shows that focal cortical dysplasia can be familial and provides clinical evidence suggesting that cortical dysplasia, hemimegalencephaly, ganglioglioma, and dysembryoplastic neuroepithelial tumors may share common genetic determinants.

Understanding what patients and their parents want is essential to plan appropriate patient-centered care. Questionnaires were distributed to 500 consecutive children and parents seen for their first pediatric neurology consultation. Both patients and their families answered questions about their expectations of the consultation, their level of worry, and the Penn State Worry Questionnaire. The 5 most important issues for the parents were to get information, to work with the doctor to manage the problem, to have questions answered, to find out what was wrong, and to discuss the impact on the child’s life. The children had very similar priorities. The 5 least important concerns for parents were to get a prescription, blood tests, to talk to others with similar problems, to get a radiograph/computed tomography/magnetic resonance imaging (MRI) and to be told nothing is wrong. The pediatric neurologists did well in anticipating these priorities but had more difficulty appreciating parent and patient level of worry.

Activation of specific cortical territories by certain stimuli is known to trigger focal seizures. We report three cases of well documented operculo-insular reflex seizures, triggered by somatosensory stimuli in two and loud noises in the third. Limited operculoinsular resection resulted in an excellent outcome for all. We discuss these observations in regard to the literature on reflex epilepsy and known functions of the insula. [Published with video sequences online].

Rationale The purposes of this study were to 1) conduct a review of neuropsychological (NP) outcomes after epilepsy surgery for DNET and 2) present pre/post-surgical NP results from a series of children with DNET. Methods First, a systematic literature review was conducted with specific inclusion criteria. Second, a review of DNET surgical patients seen at two tertiary-care hospitals using reliable change methods of NP functioning was conducted. Results Of 300 citations retrieved, 7 studies met criteria. Studies reported low average to average pre-surgical IQ. Engel Class I outcome was approximately 85%. Case Series: Thirteen children completed pre/post-surgical NP assessments. Pre-surgically, children demonstrated low average to average functioning. Post-surgically, few patients showed reliable change. One-third of children demonstrated psychological improvement. Conclusions NP outcome following DNET has not been well-described. Children with DNET demonstrate low average to average NP functioning pre-surgically, good seizure outcome, and stable NP functioning post-surgically.

Cortical dysplasia (CD) is intrinsically epileptogenic. We hypothesize that CDs clinically emerging in the early developing brain tend to extend into multifocal or larger epileptic networks to pronounce intractability in contrast to CDs which clinically emerge at a later age.We evaluated the spatial and temporal profiles of ictal-onset EEG patterns in children with histopathologically confirmed CD. We designated Group A as children with changing ictal-onset EEG patterns over time, and Group B without change. We compared seizure profiles, consecutive scalp video-EEGs (VEEGs), MRI, MEG, and surgical outcomes.We found 14 children consisting of 10 Group A patients (7 girls) and 4 Group B patients (all boys). Eight (80%) Group A patients had their seizure onset5 years while all Group B patients had seizure onsetor=5 years (p.05). Changes of ictal onset EEG pattern in Group A consisted of bilateral (4 patients), extending (2); extending and bilateral (2); and generalized (2). We saw MRI lesions (6) and single clustered MEG spike sources (MEGSSs) in (5). Six patients underwent surgery before 15 years of age, and 4 of them attained seizure freedom. All 4 Group B patients had MRI lesions and single clustered MEGSSs. Three patients underwent surgery after 15 years of age. All 4 patients attained seizure freedom.Ictal-onset EEG patterns change over time in children with early seizure onset and intractable epilepsy caused by CD. Younger epileptic children with CD more frequently have multifocal epileptogenic foci or larger epileptogenic foci. Early resection of CD, guided by MRI, MEG, and intracranial video EEG, resulted in seizure freedom despite changes in ictal-onset EEG patterns.

Patients must remain immobile for magnetoencephalography (MEG) and MRI recordings to allow precise localization of brain function for pre-surgical functional mapping. In young children with epilepsy, this is accomplished with recordings during sleep or with anesthesia. This paper demonstrates that MEG can detect, characterize and localize somatosensory-evoked fields (SEF) in infants younger than 4 years of age with or without total intravenous anesthesia (TIVA).We investigated the latency, amplitude, residual error (RE) and location of the N20m of the SEF in 26 infants (mean age=2.6 years). Seventeen patients underwent TIVA and 9 patients were tested while asleep, without TIVA.MEG detected 44 reliable SEFs (77%) in 52 median nerve stimulations. We found 27 reliable SEFs (79%) with TIVA and 13 reliable SEFs (72%) without TIVA. TIVA effects included longer latencies (p0.001) and lower RE (p0.05) compared to those without TIVA. Older patients and larger head circumferences also showed significantly shorter latencies (p0.01).TIVA resulted in reliable SEFs with lower RE and longer latencies.MEG can detect reliable SEFs in infants younger than 4 years old. When infants require TIVA for MEG and MRI acquisition, SEFs can still be reliably observed.

Summary Purpose: To study the role of magnetoencephalography (MEG) in the surgical evaluation of children with recurrent seizures after epilepsy surgery. Methods: We studied 17 children with recurrent seizures after epilepsy surgery using interictal and ictal scalp EEG, intracranial video EEG (IVEEG), MRI, and MEG. We analyzed the location and distribution of MEG spike sources (MEGSSs) and the relationship of MEGSSs to the margins of previous resections and surgical outcome. Results: Clustered MEGSSs occurred at the margins of previous resections within two contiguous gyri in 10 patients (group A), extended spatially from a margin by ≤3 cm in three patients (group B), and were remote from a resection margin by >3 cm in six patients (group C). Two patients had concomitant group A and C clusters. Thirteen patients underwent second surgeries. IVEEG was used in four patients. Six of seven patients with group A MEGSS clusters did not require IVEEG for second surgeries. Follow-up periods ranged from 0.6 to 4.3 years (mean: 2.6 years). Eleven children, including eight who became seizure-free, achieved Engel class I or II. Conclusion: Our data demonstrate the utility of MEG for evaluating patients with recurrent seizures after epilepsy surgery. Specific MEGSS cluster patterns delineate epileptogenic zones. Removing cluster regions adjacent to the margins of previous resections, in addition to removing recurrent lesions, achieves favorable surgical outcome. Cluster location and extent identify which patients require IVEEG, potentially eliminating IVEEG for some. Patients with remotely located clusters require IVEEG for accurate assessment and localization of the entire epileptogenic zone.

A previously healthy 10-year-old boy developed generalized convulsive status epilepticus following a mild febrile illness. Prolonged video-electroencephalographic monitoring revealed frequent right hemispheric electrographic seizures that were refractory to high-dose suppressive therapy. Ictal and interictal magnetoencephalography demonstrated dipole sources projecting from the right mesial temporal region. Diffusion-weighted imaging showed restricted diffusion involving the right hippocampus. Right anterior temporal lobectomy resulted in cessation of status epilepticus. At 1-year follow-up, he attends regular school and has infrequent nocturnal seizures on chronic antiepileptic drug therapy. Surgical treatment should be considered to stop status epilepticus in selected cases of acute symptomatic refractory status epilepticus with no preexisting epilepsy or magnetic resonance imaging abnormalities and may avoid the complications associated with prolonged high-dose suppressive therapy.

Gelastic seizures are relatively uncommon and rarely observed secondary to frontal lobe lesions. This report presents magnetoencephalography (MEG) and diffusion tensor imaging (DTI) findings in an adolescent with gelastic seizures secondary to a left anterior cingulate gyrus lesion. Ictal scalp video EEG showed bilateral frontal 4 Hz theta discharges. Interictal EEG showed left fronto-temporal spikes or sharp waves. Interictal MEG showed spike sources over bilateral temporal regions. DTI and tractography delineated slightly shifted corpus callosum posterior to the lesion, unaffected uncinate and inferior longitudinal fasciculi. The patient became seizure free for 12 months after surgical excision of a pleomorphic xanthoastrocytoma in the left anterior cingulate region. In our patient, MEG and EEG did not localize the deep-seated epileptogenic zone. The combination of DTI and neurophysiologic studies, however, possibly disclosed neuronal connections within the epileptic network and indicated that epileptic discharges propagated via the uncinate fibers from the primary epileptogenic zone in the anterior cingulate region to the mesial temporal region in this case with gelastic seizures secondary to a cingulate lesion.

We estimated the cost-effectiveness of adding magnetoencephalography to a standard assessment for epilepsy surgery consisting of neuropsychology, magnetic resonance imagining, scalp electroencephalography, video electroencephalography and intracranial electroencephalography, in the capacity of informing intracranial electroencephalography electrode placement.We used Microsoft Excel (2007) to construct a decision model. Discounted costs and quality adjusted life years are aggregated to calculate incremental cost-effectiveness ratios. Sensitivity analyses are conducted to assess robustness of findings.Our base case analysis yielded a result of $14 300 per quality adjusted life year gained. A total of 82.7% of probabilistic sensitivity analysis iterations resulted in incremental cost-effectiveness ratios below $100 000 in 2014 Canadian dollars.Our findings demonstrate that the inclusion of Magnetoencephalography in the assessment for epilepsy surgery in the capacity of informing intracranial electroencephalography electrode placement is likely not cost saving but does represent a reasonable allocation of resources from a value for money perspective.

SummaryObjective Infantile spasms (IS) are a severe form of childhood epilepsy associated with autism spectrum disorders (ASD) in up to 35% of cases. The objective of this post hoc analysis of our randomized control trial was to determine whether rapid diagnosis and treatment of IS could limit the incidence of ASD while identifying risk factors related to ASD outcome. Methods Patients with IS were randomized in a standardized diagnostic and treatment protocol. Clinical and electroencephalogram (EEG) evaluations were completed at all eight visits over 5 years, while cognitive evaluations were administered at 0, 6, 24 and 60 months, respectively. Autism was initially screened by means of the Checklist for Autism in Toddlers (CHAT) at 24 months, and formally assessed at the 30-and 60-month follow-ups using the Autism Diagnostic Observation Schedule—Generic (ADOS-G). Results Of the 69 patients included in the study, 25 could not be assessed due to severe delay or death. Eleven of the 42 patients screened with CHAT, were found to be at risk of an ASD outcome. ADOS was performed in 44 and 10 were diagnosed with ASD. The CHAT proved to correlate highly with the ADOS (80% ppv). Only patients with symptomatic IS developed ASD (p = 0.003). Earlier diagnosis or successful treatment did not correlate with a reduced rate of ASD. Other risk factors were identified such as having chronic epileptic discharges in the frontotemporal areas after disappearance of hypsarrhythmia (p = 0.005 and p = 0.007) and being of nonwhite origin (p = 0.009). Significance ASD was only observed in children with sympyomatic IS. Other clinical risk factors include chronic frontotemporal epileptic activity and being of non-white origin. Early diagnosis and treatment did not prevent ASD as an outcome of IS. However, patients at risk for ASD could be identified early on and should in the future benefit from early intervention to potentially improve their long-term outcome.

Objective: To characterise magnetoencephalographic spike sources in paediatric patients with auditory auras and recurrent localisation-related epilepsy. Methods: Six patients (four boys and two girls (ages 7–14 years) were retrospectively studied. All patients had auditory auras as part of their initial seizure manifestation, including four patients who underwent previous brain surgery. Scalp video electroencephalography and magnetoencephalography (MEG) were carried out in six patients, intraoperative electrocorticography in three patients and extraoperative intracranial video electroencephalography in one patient. MEG auditory-evoked fields (AEFs) were studied in four patients. Results: Three patients had elementary auditory auras, one had complex auditory aura and two had both complex and elementary auras. All six patients had clustered MEG spike sources with coexisting scattered spike sources. MEG clusters were localised in the superior temporal gyrus with surrounding scatters in four patients (two left and two right); two patients had scattered spikes in the superior temporal gyrus in addition to clustered MEG spike sources in the left inferior and middle frontal gyri or parieto-occipital region. AEFs were located within an MEG cluster in one patient and within 3 cm of a cluster in two patients. Surgical resection, including the regions of MEG clusters, was carried out in four patients. Three of four patients who had previous surgeries were seizure free at 2 years after excision of the MEG cluster region. Conclusions: MEG spike sources clustered in the superior temporal gyrus in six patients with auditory auras. These spike sources were in close proximity or seemed to engulf the magnetic AEF. Areas with MEG spike sources contained the residual or recurrent epileptogenic zone after incomplete cortical excision for lesional epilepsy.

Cognitive impairment is observed commonly in children with a history of infantile spasms (IS). The goal of this study was to prospectively examine the effect on cognitive outcome of a neuroprotective agent used as adjunctive therapy during treatment of the spasms.In a randomized controlled trial, patients received a standardized therapy plus flunarizine or placebo. The standardized treatment consisted of vigabatrin as first-line therapy. Nonresponders were switched to intramuscular synthetic adrenocorticotropic hormone (sACTH depot) after 2 weeks and, if necessary, to topiramate after two additional weeks. The Vineland Adaptive Behavior Scale (VABS) and Bayley Scales of Infant Development (BSID) were used as outcome measures 24 months after the intervention.Sixty-eight of 101 children diagnosed over 3 years in seven centers in Canada received either adjunctive flunarizine or placebo. Sixty-five of the 68 children (96%) became spasm-free within 8 weeks and no late relapse occurred. Bayley and Vineland results were available at baseline and at 24 months in 45 children. There was no significant difference in the BSID developmental quotient between the flunarizine- and placebo-treated children at baseline (44.3 ± 35.5 vs. 30.9 ± 29.8; p = 0.18) or 24 months later (56.9 ± 33.3 vs. 46 ± 34.2; p = 0.29). However, the 10 flunarizine-treated children with no identified etiology had a better outcome than the eight controls at 24 months on both the Vineland Scale (84.1 ± 11.3 vs. 72.3 ± 9.8; p = 0.03) and the Bayley Scale (87.6 ± 14.7 vs. 69.9 ± 25.3; p = 0.07).Our study failed to demonstrate a protective effect of flunarizine on cognitive outcome in a cohort of children with IS. An analysis of subgroups suggested that flunarizine may further improve cognitive outcome in children with no identified etiology.

Objective To evaluate the utility of an event-related beamforming (ERB) algorithm in source localization of interictal discharges. Methods We analyzed interictal magnetoencephalography data in 35 children with intractable neocortical epilepsy. We used a spatiotemporal beamforming method to estimate the spatial distribution of source power in individual interictal spikes. We compared ERB results to source localization using the equivalent current dipole model and to the seizure onset zones on intracranial EEG. Results Focal beamformer localization was observed in 66% of patients and multifocal in the remaining 34%. ERB localized within 2 cm of the equivalent current dipole cluster centroid in 77% of the patients. ERB localization was concordant with the seizure onset zone on intracranial EEG at the gyral level in 69% of patients. Focal ERB localization area was included in the resection margin in 22/23 patients. However, focal ERB localization was not statistically associated with better surgical outcome. Conclusions ERB can be used for source localization of interictal spikes and can be predictive of the ictal onset zone in a subset of patients with neocortical epilepsy. Significance These results support the utility of beamformer source localization as a fast semi-automated method for source localization of interictal spikes and planning the surgical strategy.

A previously healthy five year-old boy was seen after intermittent strangulation attempts over the course of two days. Details of the event are vague due to lack of reliable adult witnesses. There was no indication of toxic exposure. General examination on arrival to the emergency department revealed an alert boy with bruising of the neck consistent with multiple strangulation attempts. There was no evidence of heart, kidney, or liver involvement to suggest systemic hypoperfusion or organ failure. Investigations done on arrival showed no acidosis, and a capillary blood gas 48 hours later revealed a normal carboxyhemoglobin. Although the initial neurologic exam was near normal, severe generalized dystonia developed over the next four weeks, requiring intrathecal baclofen treatment.

Objective:To determine the correlation between frontal intermittent rhythmic delta activity (FIRDA) and the clinical and radiological correlates in children.Methods:Retrospective review of the EEG and imaging studies of 37 children with documented FIRDA.Results:FIRDA was associated with multiple neurological conditions and not necessarily with midline lesions. Patients with abnormal neurological exam had a longer FIRDA duration (average 9.5 seconds) compared to children with no reported abnormal examination (average of 6.5 seconds). FIRDA ranged from 2 to 2.5 Hz (n=15), 3 Hz (n=17) and from 1.5 to 3 Hz (n=5) and there was a significant association between the duration of FIRDA and abnormal laboratory tests (p. < 0.05, Student's T test).Conclusion:FIRDA was not correlated with midline brain lesions in children. FIRDA may be a non specific oscillation of an unhealthy pediatric brain with or without seizures.

Background – A child whose left temporal lobe contained mesial, anterior and basal structures but lacked superio-lateral cortex had intractable epilepsy secondary to a porencephalic cyst. Magnetoencephalography (MEG) shows equivalent current dipoles (ECDs) as dipole modeling for temporal lobe epilepsy rather than in an exact location. Aim – We hypothesized that the magnetic fields generated by the epileptic discharges in mesio-basal temporal areas could be detected by MEG without interference from the superio-lateral temporal cortices. Methods – We analyzed MEG spikes using single dipole analysis and synthetic aperture magnetometry (SAM), and compared with EEG spike topography. Results – Two MEG ECDs corresponding to T3 spikes localized to the anterior mesio-basal temporal region with vertical orientation. Sixteen MEG ECDs corresponding to T5 spikes localized to the middle to posterior mesio-basal temporal region with vertical orientation. SAM revealed maximum current density at hippocampus and anterior fusiform gyrus for T3 spikes, and at posterior hippocampus and fusiform gyrus for T5 spikes. Conclusion – Vertically oriented ECDs were obtained without superio-lateral temporal cortices because of temporo-parieto-occipital porencephalic cyst. The absence of superio-lateral temporal cortices, prominent temporal EEG spikes, less prominent MEG spikes, and mesio-basal SAM spikes indicated that the vertically oriented ECDs were projected directly from the mesio-basal temporal region.

Objective We studied the task-induced spatiotemporal evolution and characteristics of cortical neural oscillations in children during an auditory word recognition task. Methods We presented abstract nouns binaurally and recorded the MEG response in eight healthy right-handed children (6–12 years). We calculated the event-related changes in cortical oscillations using a beamformer spatial filter analysis technique (SAM), then transformed each subject's statistical maps into standard space and used these to make group statistical inferences. Results Across subjects, the cortical response to words could be divided into at least two phases: an initial event-related synchronization in both the right temporal (100–300 ms, 15–25 Hz; 200–400 ms, 5–15 Hz) and left frontal regions (200–400 ms; 15–25 Hz); followed by a strong left-lateralized event-related desynchronization in the left temporal region (500–700 ms; 5–15 Hz). Conclusions We found bilateral event-related synchronization followed by later left lateralized event-related desynchronization in language-related cortical areas. These data demonstrate the spatiotemporal time course of neural activation during an auditory word recognition task in a group of children. As well, this demonstrates the utility of SAM analyses to detect subtle sequential task-related neural activations.

Magnetoencephalography (MEG) provides accurate localizing information of the epileptogenic zones in localization-related epilepsies. Refractory status epilepticus (RSE) is a life-threatening emergency that often requires prolonged high-dose suppressive therapy (HDST) to stop frequent and prolonged seizures. Surgical treatments for patients with RSE secondary to pre-existing epilepsy were reported. This article addresses the role of MEG in localizing the epileptogenic zone for the surgical treatment of patients with RSE. Five pediatric patients with RSE underwent epilepsy surgery using MEG, scalp video EEG and magnetic resonance imaging (MRI). Ictal MEG spike sources (MEGSSs) were localized in the clustered interictal MEGSSs in right Rolandic region (patient 3) and right temporal region (patient 5). Interictal MEG revealed unilateral clustered MEGSSs in four patients (patients 1, 2, 4, and 5) and bilateral (patient 3). Ictal-onset EEG findings were localized to one region in three patients (patients 1, 3, and 5) and two regions in the other two patients (patients 2 and 4). In all five patients, interictal discharges were widespread involving over two lobes (patients 2 and 4) or three lobes (patients 1, 3, and 5). Suppression burst pattern was obtained by HDST (patient 5). MRI showed cortical dysplasia in three patients (patients 1, 3, and 4). Patient 2 had a normal MRI. Patient 5 had normal MRI at the onset. Repeat MRI 5 days later showed diffusion restriction in the right hippocampus associated with increased signal intensity on T2 and FLAIR sequences. We performed cortical excision in two patients (patients 1 and 4), hemispherectotomy one (patient 3) and anterior temporal lobectomy two patients (patients 2 and 5). Two patients (patients 1 and 3) became seizure free, the other three patients experienced residual seizures. MEG showed clustered MEGSSs during the RSE in the pre-existing epilepsy patients and at an early time window in the acute symptomatic RSE patients. The complete resection of clustered MEGSSs can control RSE and possibly lead to a seizure free outcome.

Summary: Purpose: Tuberous sclerosis complex (TSC) often causes medically intractable seizures. Magnetoencephalography (MEG) localizes epileptiform discharges. To evaluate the use of MEG spike sources (MEGSSs) for localizing epileptic zones in TSC patients, we characterized MEGSSs and correlated them to EEG and magnetic resonance imaging (MRI) results. Methods: We analyzed data from seven children who underwent prolonged video-EEG, MEG, and MRI. We classified MEGSSs as clusters (six or more spike sources, ≤1 cm between sources) and scatters (fewer than six spike sources regardless of distance between sources; sources with >1 cm between sources regardless of number of sources). Results: A single, unilateral cluster with additional scatters occurred in two patients; these predominantly lateralized dipoles correlated to prominent tubers on MRI and ictal/interictal EEG zones. Bilateral clusters with scatters existed in two patients; cluster locations partly overlapped multiple prominent tubers. These patients also had bilateral or diffuse interictal discharges, bilateral or generalized seizures, and changing seizure types and EEG findings. Only bilateral scatters occurred in three patients; scatters partly overlapped EEG interictal/ictal-onset regions; one patient had coexisting generalized seizures. In one patient with equally bilateral scatters, scatters overlapped a prominent tuber and interictal/ictal-onset zones in the right frontal region. Conclusions: MEG contributes to information from EEG and MRI for localizing epileptogenic zones in children with TSC. A single cluster with scatters in a unilateral hemisphere predicts a primary epileptogenic zone or hemisphere; bilateral or multiple clusters indicate bilateral primary or potential epileptogenic zones; and bilateral scatters without clusters may indicate epileptogenic zones that are hidden within extensive areas of scattered MEGSSs.