Post-ictal Rhythmic Thalamic Activity of the Centromedian Nucleus.

INTRODUCTION: Deep brain stimulation of the centromedian nucleus of the thalamus (CMN) to treat drug-resistant epilepsy has been of interest for decades. However, little is known about the electrophysiological activity of the CMN during seizures. We describe a novel CMN EEG finding associated with seizure: post-ictal rhythmic thalamic activity. METHODS: Five patients with drug-resistant epilepsy of unknown etiology with focal onset seizures underwent stereoelectroencephalography monitoring as part of evaluation for potential resective surgery or neuromodulation. Two patients had previously undergone complete corpus callosotomy and vagus nerve stimulation. A standardized plan for implantation included targets in the bilateral CMN. RESULTS: Each patient had frontal onset seizures, and two patients had additional insular, parietal, or mesial temporal onset seizures. Contacts of CMN were involved synchronously or rapidly after onset in most recorded seizures, particularly those with frontal onset. Focal onset hemiclonic and bilateral tonic-clonic seizures spread to involve cortical contacts with high-amplitude rhythmic spiking followed by abrupt offset with diffuse voltage attenuation. A post-ictal rhythmic 1.5 to 2.5 Hz delta frequency pattern, post-ictal rhythmic thalamic activity, emerged in CMN contacts amid the suppression of background activity in cortical contacts. In the two patients with corpus callosotomy, unilateral seizure spread and ipsilateral post-ictal rhythmic thalamic activity were observed. CONCLUSIONS: We observed post-ictal rhythmic thalamic activity in five patients with stereoelectroencephalography monitoring of the CMN with convulsive seizures. This rhythm appears late in ictal evolution and may signal an important role of the CMN in seizure termination. Furthermore, this rhythm may help identify CMN involvement in the epileptic network.

Associations between testing and treatment pathways in lesional temporal or extratemporal epilepsy: A census survey of NAEC center directors.

OBJECTIVE: The evaluation to determine candidacy and treatment for epilepsy surgery in persons with drug-resistant epilepsy (DRE) is not uniform. Many non-invasive and invasive tests are available to ascertain an appropriate treatment strategy. This study examines expert response to clinical vignettes of magnetic resonance imaging (MRI)-positive lesional focal cortical dysplasia in both temporal and extratemporal epilepsy to identify associations in evaluations and treatment choice. METHODS: We analyzed annual report data and a supplemental epilepsy practice survey reported in 2020 from 206 adult and 136 pediatric epilepsy center directors in the United States. Non-invasive and invasive testing and surgical treatment strategies were compiled for the two scenarios. We used chi-square tests to compare testing utilization between the two scenarios. Multivariable logistic regression modeling was performed to assess associations between variables. RESULTS: The supplemental survey response rate was 100% with 342 responses included in the analyses. Differing testing and treatment approaches were noted between the temporal and extratemporal scenarios such as chronic invasive monitoring selected in 60% of the temporal scenario versus 93% of the extratemporal scenario. Open resection was the most common treatment choice; however, overall treatment choices varied significantly (p < .001). Associations between non-invasive testing, invasive testing, and treatment choices were present in both scenarios. For example, in the temporal scenario stereo-electroencephalography (SEEG) was more commonly associated with fluorodeoxyglucose-positron emission tomography (FDG-PET) (odds ratio [OR] 1.85; 95% confidence interval [CI] 1.06-3.29; p = .033), magnetoencephalography (MEG) (OR 2.90; 95% CI 1.60-5.28; p = <.001), high density (HD) EEG (OR 2.80; 95% CI 1.27-6.24; p = .011), functional MRI (fMRI) (OR 2.17; 95% CI 1.19-4.10; p = .014), and Wada (OR 2.16; 95% CI 1.28-3.66; p = .004). In the extratemporal scenario, choosing SEEG was associated with increased odds of neuromodulation over open resection (OR 3.13; 95% CI 1.24-7.89; p = .016). SIGNIFICANCE: In clinical vignettes of temporal and extratemporal lesional DRE, epilepsy center directors displayed varying patterns of non-invasive testing, invasive testing, and treatment choices. Differences in practice underscore the need for comparative trials for the surgical management of DRE.

Health Disparities in Pediatric Epilepsy: Methods and Lessons Learned.

Epilepsy affects 1% of youth and is associated with neurocognitive and psychosocial comorbidities, increased risk of mortality, and poor health-related outcomes. Health disparities in children and youth with epilepsy (CYE) have been understudied. A Special Interest Group (SIG) within the Pediatric Epilepsy Research Consortium is conducting a scoping review to systematically assess the literature and highlight the gaps in access to clinical care and management of pediatric epilepsy. The methodology for this review is presented. In conducting a peer-reviewed assessment of the scope of health disparities in pediatric epilepsy, we learned that developing the methodology for and conducting a comprehensive scoping review with multiple contributors resulted in a time-intensive process. While there is an evidence to suggest that health disparities do exist in CYE, very few studies have focused on these disparities. Disparity results are often not included in key elements of articles, lending them to be underemphasized and underrecognized. Preliminary conclusions inform several important research considerations.

Prioritizing Hormone Therapy Over Vigabatrin as the First Treatment for Infantile Spasms: A Quality Improvement Initiative.

BACKGROUND AND OBJECTIVES: Infantile spasms (IS) are early childhood seizures with potentially devastating consequences. Standard therapies (adrenocorticotropic hormone [ACTH], high-dose prednisolone, and vigabatrin) are strongly recommended as the first treatment for IS. Although this recommendation comes without preference for one standard therapy over another, early remission rates are higher with hormone therapy (ACTH and high-dose prednisolone) when compared with vigabatrin. Using quality improvement (QI) methodology that included hormone therapy as the first treatment, we sought to increase the percentage of children with new-onset nontuberous sclerosis complex (TSC)-associated IS achieving 3-month electroclinical remission from a mean of 53.8% to ≥70%. METHODS: This was an observational consecutive sample cohort study at a single academic tertiary care hospital that compared a prospective intervention cohort (May 2019-January 2022, N = 57) with a retrospective baseline cohort (November 2015-April 2019, N = 67). Our initiative addressed key drivers such as the routine use of vigabatrin over hormone therapy as first treatment and the common initiation of a second treatment after 14 days for initial nonresponders. We included consecutive children without TSC presenting with new-onset IS diagnosed and treated between ages 2 and 24 months. We displayed our primary outcome and process measures as control charts in which the centerline is the quarterly (previous 3 months) mean based on statistical process control methodology. RESULTS: QI interventions that included the standardization of hormone therapy as the first treatment resulted in higher rates of 3-month remission, rising from 53.8% (baseline cohort) to 75.9% (intervention cohort). Process measure results included an increased rate of children receiving hormone therapy as first treatment (mean, 44.6%-100%) and a decreased number of days to both clinical follow-up after first treatment (mean, of 16.3-12.6 days) and starting a second treatment within 14 days for initial nonresponders (mean, 36.3-17.2 days). DISCUSSION: For children with IS, improved rates of 3-month electroclinical remission can be achieved with QI methodology. Implementation of similar QI initiatives at other centers may likewise improve local remission rates.

The Missed Value of Underutilizing Pediatric Epilepsy Surgery: A Systematic Review.

Pediatric epilepsy surgery is underutilized. Only 1%-11% of children with drug resistant epilepsy (DRE) undergo surgical treatment, or less than half of those estimated to benefit. We conducted a systematic review of articles published in PubMed, EMBASE, and Web of Science in order to study the factors related to surgery underutilization as well as the impact on both the individual and the healthcare system. Our review demonstrates multiple factors leading to underutilization, including family misconceptions about epilepsy surgery, lack of provider knowledge, as well as systemic health disparities. While the upfront cost of epilepsy surgery is significant, the long-term financial benefits and reduced health resource utilization tilt the economic advantage in favor of surgery in children with DRE. Additionally, timely interventions improve seizure and cognitive outcomes with low risk of complications. Further interventions are needed at the levels of family, provider, and the healthcare system to increase access to pediatric epilepsy surgery.

Provider Practices of Phenobarbital Discontinuation in Neonatal Seizures.

Neonatal seizures are treated with phenobarbital and prolonged treatment does not prevent postneonatal epilepsy. The authors documented factors influencing phenobarbital use and determined whether published data changed practice. A total of 83 neonates with symptomatic seizures, clinical or electrographic, were evaluated for treatment, incidence of postneonatal epilepsy, and associated factors. Median phenobarbital treatment was 81 days. Nineteen children (23%) developed postneonatal epilepsy. Longer duration of seizures and an infectious etiology were associated with postneonatal epilepsy suggesting no impact on duration of phenobarbital treatment. Treatment duration was associated with duration of seizures and use of a second antiseizure medication. This study supports early discontinuation of phenobarbital and suggests providers utilize factors such as use of a second antiseizure medication and time to seizure control to determine phenobarbital duration, despite prior studies suggesting no impact of treatment length.

Diagnosis, treatment, and outcomes of infantile spasms in the Trisomy 21 population.

PURPOSE: To determine if there are differences in the timing of diagnosis and response to treatment between infants with infantile spasms (IS) and Trisomy 21 (T21) and those with idiopathic IS. METHOD: This was a retrospective study evaluating the time from onset of IS to diagnosis, treatment of IS, time from treatment to resolution of IS, and development of epilepsy in children with T21 and IS compared to children with idiopathic IS. RESULTS: Thirteen children with T21 and IS were identified over a 10 year period and compared to 32 children in the control group. There was no significant difference in age of onset, time between onset and diagnosis, or acute response to treatment. However, the children with idiopathic IS were more likely to go on to develop epilepsy than those with T21 and IS (41% vs. 0, p=0.006). CONCLUSION: The children with T21 and IS were diagnosed and treated similarly to those patients with idiopathic IS. There were no significant differences in the age of onset, time between the onset and diagnosis of IS, or acute treatment response of IS between the T21 and control groups. However those with T21 and IS had a lower risk of subsequent epilepsy following IS than those with idiopathic IS. IS in the T21 population appears to be inherently different from IS of unknown etiology.

Dramatic Response After Lamotrigine in a Patient With Epileptic Encephalopathy and a De NovoCACNA1A Variant.

BACKGROUND: Channelopathies are a group of monogenic disorders that affect a single ion channel and can result in neurological disease. While a rare cause of epilepsy, channelopathies offer unique insight to the molecular basis of epilepsy and treatment opportunities. Calcium homeostasis is tightly regulated by a series of interacting subunits. CACNA1A encodes the principal pore-forming subunit of the voltage-gated P/Q-type calcium channel, alpha1. Patients with epileptic encephalopathy due to pathogenic variants in CACNA1A have been previously described and are challenging to treat. PATIENT DESCRIPTION: We describe a child with epileptic encephalopathy, ataxia, cognitive impairment, and significant social-behavioral abnormalities due to a de novo pathogenic variant, p.S1373L in the CACNA1A gene. After failing zonisamide and divalproex sodium, she had a dramatic response to lamotrigine with a precipitous decrease in seizure frequency and severity. This improvement has persisted over one year. CONCLUSION: While classically thought to act at sodium channels, lamotrigine also modulates the activity of the P/Q-type calcium channel, making it a candidate for precision therapy for patients with epileptic encephalopathy due to CACNA1A pathogenic variants. The rarity and clinical heterogeneity of epilepsy due to variants in CACNA1A presents challenges to clinical diagnosis. However, genetic analysis for patients with epilepsy continues to expand; additional patients are likely to be identified molecularly. Lamotrigine should be considered as a first-line treatment in patients with epileptic encephalopathy due to pathogenic variants in CACNA1A.

Delayed-onset movement disorder and encephalopathy after oxycodone ingestion.

We present the case of a 14-year-old girl with a biphasic course after oxycodone ingestion. Clinically, she had a rapid return to baseline after initial ingestion and presented a week later with new-onset ballism, akathisia, and encephalopathy. Neuroimaging demonstrated bilateral globi pallidi and cerebellar lesions with a relative decrease of metabolite peaks on magnetic resonance spectroscopy. Her movement disorder was treated successfully with valproic acid and clonidine. Her cognitive functioning returned to baseline 3 months after ingestion.