Source EEG reveals that Rolandic epilepsy is a regional epileptic encephalopathy.

Rolandic epilepsy is the most common form of epileptic encephalopathy, characterized by sleep-potentiated inferior Rolandic epileptiform spikes, seizures, and cognitive deficits in school-age children that spontaneously resolve by adolescence. We recently identified a paucity of sleep spindles, physiological thalamocortical rhythms associated with sleep-dependent learning, in the Rolandic cortex during the active phase of this disease. Because spindles are generated in the thalamus and amplified through regional thalamocortical circuits, we hypothesized that: 1) deficits in spindle rate would involve but extend beyond the inferior Rolandic cortex in active epilepsy and 2) regional spindle deficits would better predict cognitive function than inferior Rolandic spindle deficits alone. To test these hypotheses, we obtained high-resolution MRI, high-density EEG recordings, and focused neuropsychological assessments in children with Rolandic epilepsy during active (n = 8, age 9-14.7 years, 3F) and resolved (seizure free for > 1 year, n = 10, age 10.3-16.7 years, 1F) stages of disease and age-matched controls (n = 8, age 8.9-14.5 years, 5F). Using a validated spindle detector applied to estimates of electrical source activity in 31 cortical regions, including the inferior Rolandic cortex, during stages 2 and 3 of non-rapid eye movement sleep, we compared spindle rates in each cortical region across groups. Among detected spindles, we compared spindle features (power, duration, coherence, bilateral synchrony) between groups. We then used regression models to examine the relationship between spindle rate and cognitive function (fine motor dexterity, phonological processing, attention, and intelligence, and a global measure of all functions). We found that spindle rate was reduced in the inferior Rolandic cortices in active but not resolved disease (active P = 0.007; resolved P = 0.2) compared to controls. Spindles in this region were less synchronous between hemispheres in the active group (P = 0.005; resolved P = 0.1) compared to controls; but there were no differences in spindle power, duration, or coherence between groups. Compared to controls, spindle rate in the active group was also reduced in the prefrontal, insular, superior temporal, and posterior parietal regions (i.e., "regional spindle rate", P < 0.039 for all). Independent of group, regional spindle rate positively correlated with fine motor dexterity (P < 1e-3), attention (P = 0.02), intelligence (P = 0.04), and global cognitive performance (P < 1e-4). Compared to the inferior Rolandic spindle rate alone, models including regional spindle rate trended to improve prediction of global cognitive performance (P = 0.052), and markedly improved prediction of fine motor dexterity (P = 0.006). These results identify a spindle disruption in Rolandic epilepsy that extends beyond the epileptic cortex and a potential mechanistic explanation for the broad cognitive deficits that can be observed in this epileptic encephalopathy.

Feasibility and Acceptance of Direct-to-Home Tele-neuropsychology Services during the COVID-19 Pandemic.

OBJECTIVE: Neuropsychological assessment via video conferencing has been proposed during the COVID-19 pandemic. Existing literature has demonstrated feasibility and acceptance of neuropsychological measures administered by videoconference, although few studies have examined feasibility and patient acceptance of TNP visits directly to patients' homes (DTH-TNP). METHODS: We modified a previously published patient satisfaction survey for DTH-TNP and developed a clinician feasibility survey to examine experiences during DTH-TNP. RESULTS: Seventy-two patients (age range: preschool-geriatric) evaluated by DTH-TNP for cognitive problems at an academic medical center responded to voluntary surveys between April 20, 2020, and August 19, 2020, and 100% indicated satisfaction. Fifty-nine percent of patients reported limitations (e.g., technological concern) during the appointment. 134 clinician surveys were collected and indicated that clinicians achieved the goal of their appointment in 90% of encounters. CONCLUSIONS: These qualitative data suggest that patients and clinicians found DTH-TNP to be satisfactory during the COVID-19 pandemic, while also recognizing limitations of the practice. These results are limited in that voluntary surveys are subject to bias. They support the growing body of literature suggesting that DTH-TNP provides a valuable service, though additional research to establish reliability and validity is needed.

Focal Sleep Spindle Deficits Reveal Focal Thalamocortical Dysfunction and Predict Cognitive Deficits in Sleep Activated Developmental Epilepsy.

Childhood epilepsy with centrotemporal spikes (CECTS) is the most common focal epilepsy syndrome, yet the cause of this disease remains unknown. Now recognized as a mild epileptic encephalopathy, children exhibit sleep-activated focal epileptiform discharges and cognitive difficulties during the active phase of the disease. The association between the abnormal electrophysiology and sleep suggests disruption to thalamocortical circuits. Thalamocortical circuit dysfunction resulting in pathologic epileptiform activity could hinder the production of sleep spindles, a brain rhythm essential for memory processes. Despite this pathophysiologic connection, the relationship between spindles and cognitive symptoms in epileptic encephalopathies has not been previously evaluated. A significant challenge limiting such work has been the poor performance of available automated spindle detection methods in the setting of sharp activities, such as epileptic spikes. Here, we validate a robust new method to accurately measure sleep spindles in patients with epilepsy. We then apply this detector to a prospective cohort of male and female children with CECTS with combined high-density EEGs during sleep and cognitive testing at varying time points of disease. We show that: (1) children have a transient, focal deficit in spindles during the symptomatic phase of disease; (2) spindle rate anticorrelates with spike rate; and (3) spindle rate, but not spike rate, predicts performance on cognitive tasks. These findings demonstrate focal thalamocortical circuit dysfunction and provide a pathophysiological explanation for the shared seizures and cognitive symptoms in CECTS. Further, this work identifies sleep spindles as a potential treatment target of cognitive dysfunction in this common epileptic encephalopathy.SIGNIFICANCE STATEMENT Childhood epilepsy with centrotemporal spikes is the most common idiopathic focal epilepsy syndrome, characterized by self-limited focal seizures and cognitive symptoms. Here, we provide the first evidence that focal thalamocortical circuit dysfunction underlies the shared seizures and cognitive dysfunction observed. In doing so, we identify sleep spindles as a mechanistic biomarker, and potential treatment target, of cognitive dysfunction in this common developmental epilepsy and provide a novel method to reliably quantify spindles in brain recordings from patients with epilepsy.

Dysmature superficial white matter microstructure in developmental focal epilepsy.

Benign epilepsy with centrotemporal spikes is a common childhood epilepsy syndrome that predominantly affects boys, characterized by self-limited focal seizures arising from the perirolandic cortex and fine motor abnormalities. Concurrent with the age-specific presentation of this syndrome, the brain undergoes a developmentally choreographed sequence of white matter microstructural changes, including maturation of association u-fibres abutting the cortex. These short fibres mediate local cortico-cortical communication and provide an age-sensitive structural substrate that could support a focal disease process. To test this hypothesis, we evaluated the microstructural properties of superficial white matter in regions corresponding to u-fibres underlying the perirolandic seizure onset zone in children with this epilepsy syndrome compared with healthy controls. To verify the spatial specificity of these features, we characterized global superficial and deep white matter properties. We further evaluated the characteristics of the perirolandic white matter in relation to performance on a fine motor task, gender and abnormalities observed on EEG. Children with benign epilepsy with centrotemporal spikes (n = 20) and healthy controls (n = 14) underwent multimodal testing with high-resolution MRI including diffusion tensor imaging sequences, sleep EEG recordings and fine motor assessment. We compared white matter microstructural characteristics (axial, radial and mean diffusivity, and fractional anisotropy) between groups in each region. We found distinct abnormalities corresponding to the perirolandic u-fibre region, with increased axial, radial and mean diffusivity and fractional anisotropy values in children with epilepsy (P = 0.039, P = 0.035, P = 0.042 and P = 0.017, respectively). Increased fractional anisotropy in this region, consistent with decreased integrity of crossing sensorimotor u-fibres, correlated with inferior fine motor performance (P = 0.029). There were gender-specific differences in white matter microstructure in the perirolandic region; males and females with epilepsy and healthy males had higher diffusion and fractional anisotropy values than healthy females (P ≤ 0.035 for all measures), suggesting that typical patterns of white matter development disproportionately predispose boys to this developmental epilepsy syndrome. Perirolandic white matter microstructure showed no relationship to epilepsy duration, duration seizure free, or epileptiform burden. There were no group differences in diffusivity or fractional anisotropy in superficial white matter outside of the perirolandic region. Children with epilepsy had increased radial diffusivity (P = 0.022) and decreased fractional anisotropy (P = 0.027) in deep white matter, consistent with a global delay in white matter maturation. These data provide evidence that atypical maturation of white matter microstructure is a basic feature in benign epilepsy with centrotemporal spikes and may contribute to the epilepsy, male predisposition and clinical comorbidities observed in this disorder.

Beta oscillations in the sensorimotor cortex correlate with disease and remission in benign epilepsy with centrotemporal spikes.

INTRODUCTION: Benign epilepsy with centrotemporal spikes (BECTS) is a common form of childhood epilepsy with the majority of those afflicted remitting during their early teenage years. Seizures arise from the lower half of the sensorimotor cortex of the brain (e.g. seizure onset zone) and the abnormal epileptiform discharges observed increase during NREM sleep. To date no clinical factors reliably predict disease course, making determination of ongoing seizure risk a significant challenge. Prior work in BECTS have shown abnormalities in beta band (14.9-30 Hz) oscillations during movement and rest. Oscillations in this frequency band are modulated by state of consciousness and thought to reflect intrinsic inhibitory mechanisms. METHODS: We used high density EEG and source localization techniques to examine beta band activity in the seizure onset zone (sensorimotor cortex) in a prospective cohort of children with BECTS and healthy controls during sleep. We hypothesized that beta power in the sensorimotor cortex would be different between patients and healthy controls, and that beta abnormalities would improve with resolution of disease in this self-limited epilepsy syndrome. We further explored the specificity of our findings and correlation with clinical features. Statistical testing was performed using logistic and standard linear regression models. RESULTS: We found that beta band power in the seizure onset zone is different between healthy controls and BECTS patients. We also found that a longer duration of time spent seizure-free (corresponding to disease remission) correlates with lower beta power in the seizure onset zone. Exploratory spatial analysis suggests this effect is not restricted to the sensorimotor cortex. Exploratory frequency analysis suggests that this phenomenon is also observed in alpha and gamma range activity. We found no relationship between beta power and the presence or rate of epileptiform discharges in the sensorimotor cortex or a test of sensorimotor performance. CONCLUSION: These results provide evidence that cortical beta power in the seizure onset zone may provide a dynamic physiological biomarker of disease in BECTS.

Low glycemic index treatment for seizures in Angelman syndrome.

PURPOSE: The low glycemic index treatment (LGIT) is a high fat, limited carbohydrate diet used in the treatment of epilepsy. The purpose of this study was to assess the efficacy and tolerability of the LGIT for the treatment of refractory seizures in pediatric patients with Angelman syndrome. METHODS: A pediatric Angelman syndrome cohort with refractory epilepsy was treated with the LGIT and followed prospectively over 4 months. Parents recorded a daily seizure log for a minimum of 1 month prior to the start of treatment as well as throughout the LGIT trial. Electroencephalography (EEG) and neuropsychological assessments (Scales of Independent Behavior-Revised and the Vineland Adaptive Behavior Scales-2nd Edition were obtained for each subject at both baseline and 4-month follow-up time points. Clinical evaluations of subjects were completed by a neurologist and dietitian at the time of enrollment, as well as following both the first and fourth months of dietary therapy. At each time point, blood for laboratory chemistries was drawn and anthropometric measures were obtained. KEY FINDINGS: Six children (mean age 3.3 years, range 1.1-4.8) with genetically confirmed Angelman syndrome initiated the LGIT, and completed the trial with no significant adverse events. Cohort averages for indices of seizure severity were as follows: age of 1.6 years at seizure onset, 3 lifetime antiepileptic drugs tried (range 1-6), and baseline seizure frequency of 10.1 events/week (range: 0.4-30.9). All subjects had a decrease in seizure frequency on the LGIT, with five of six exhibiting >80% seizure frequency reduction. All posttrial EEG studies showed improvement and three of four children with epileptiform activity on his or her baseline EEG had no discharges present on follow-up EEG. Developmental gains were noted by parents in all cases, although few of these neurocognitive gains were statistically significant on neuropsychological assessment. SIGNIFICANCE: This is the first prospective study assessing the LGIT for epilepsy. Our results indicate that this dietary therapy is highly effective in treating Angelman syndrome-related seizures. The diet was well tolerated by subjects as evidenced by five of six subjects remaining on the LGIT after completion of the trial. Beyond the prospective trial window, all five subjects who remained on the diet had >90% seizure reduction after 1 year of LGIT therapy. Despite the small sample size in this prospective study, the results indicate a potentially higher degree of efficacy of the LGIT for the Angelman syndrome population than that observed in the general epilepsy population. Although this study is too small to make definitive recommendations, these results suggest that the LGIT is a promising treatment option for Angelman syndrome-related epilepsy.

A karate program for improving self-concept and quality of life in childhood epilepsy: results of a pilot study.

The potential cognitive and psychosocial effects of childhood epilepsy have significant implications for a child's self-image and academic achievement. This study focuses on a 10-week karate program for children and adolescents with epilepsy aimed at increasing social confidence, self-concept, and quality of life, as well as reducing parental anxiety. Eleven children (8-16 years old) and their parents participated in this questionnaire study, and complete data were available for nine of these families. Measures consisted of the Piers-Harris Children's Self-Concept Scale, the Quality of Life in Childhood Epilepsy (QOLCE) questionnaire, and the Parental Stress Index. By parental report, significant improvement in memory function and largely positive trends in quality of life on multiple subscales were observed. By child report, intellectual self-esteem and social confidence also improved. Parental stress decreased, although not significantly, suggesting a potential benefit and indicating a role for future interventions targeting family anxiety.