Loddenkemper, Tobias

Abstract Objective The objective of this study is to characterize contemporary surgical management practices and factors influencing surgical decision‐making in the management of Lennox–Gastaut Syndrome (LGS) across pediatric epilepsy centers in the United States. Methods A 45‐item cross‐sectional survey was developed and distributed to Pediatric Epilepsy Research Consortium centers. Domains included institutional demographics, surgical evaluation timing and goals, presurgical workup, procedural utilization and outcomes, and barriers to surgery. Descriptive statistics and thematic analysis were performed. Results Thirty‐two pediatric epilepsy centers participated (38% response), the majority comprising pediatric epileptologists at Level 4 National Association of Epilepsy Centers. Most centers (66%) considered surgery after failure of 3–4 antiseizure medications. Presurgical workup typically included brain magnetic resonance imaging (MRI), long‐term electroencephalography (EEG) monitoring, and neuropsychological assessment, while use of functional imaging, magnetoencephalography, and intracranial EEG varied considerably. All centers offered vagus nerve stimulation and corpus callosotomy; 80%–90% offered resection, hemispherectomy, responsive neurostimulation (RNS); 60%–65% offered deep brain stimulation (DBS) and laser ablation. Among centers offering RNS, half targeted thalamic structures exclusively, and the remainder targeted cortical or combined cortical‐thalamic structures; the centromedian nucleus was the preferred thalamic target for RNS and DBS. Surgical decision‐making was influenced by patient characteristics, procedural considerations, and systemic factors. Seizure frequency, family preference, and multidisciplinary input were highly rated across all interventions. Etiology was critical for resection and hemispherectomy, while financial constraints, insurance barriers, and the need for future neuroimaging impacted neuromodulation selection. Scenario‐specific trends included less frequent consideration of DBS and RNS in children under five years, less use of hemispherectomy in older children, preference for corpus callosotomy in children with predominantly drop seizures, and procedural selection based on MRI findings. Significance Substantial variability exists in the surgical management of LGS. These findings highlight critical opportunities to harmonize practices, reduce disparities, and guide comparative effectiveness research to optimize outcomes. Plain Language Summary Lennox–Gastaut Syndrome (LGS) is a severe form of epilepsy that may require surgery when medications are not effective. This study found that surgical care for LGS varies widely across pediatric epilepsy centers in the United States, including when surgery is recommended, how patients are evaluated, and which procedures are available. Newer approaches such as brain stimulation are being used more often, although access remains inconsistent. These findings highlight the need for clearer treatment pathways to ensure that children with LGS have equitable access to the best possible care.

Abstract Objective This study was undertaken to evaluate the response to second treatments for infantile epileptic spasms syndrome (IESS). Methods Infants aged 2–24 months with IESS were prospectively enrolled in the National Infantile Spasms Cohort study at 21 pediatric epilepsy centers in the United States from 2012 to 2018. We analyzed data from infants who initially received standard treatment (hormonal therapy [adrenocorticotropic hormone, high‐dose prednisolone] or vigabatrin), had continued or recurring epileptic spasms, and received a second treatment. We excluded those with tuberous sclerosis. Treatment groups included hormonal therapy followed by vigabatrin (reference), hormonal‐to‐hormonal, hormonal‐to‐nonstandard, vigabatrin‐to‐hormonal, and vigabatrin‐to‐nonstandard. Nonstandard treatments included other antiseizure medications and dietary therapy. Treatment groups were tested for differences in 3‐month clinical remission using a binary logistic regression to estimate odds ratios (ORs). Results There were 153 infants with IESS who received second treatments. The highest rates of 3‐month remission were among infants in the hormonal‐to‐vigabatrin (22/65, 34%) and vigabatrin‐to‐hormonal (9/26, 35%) groups, followed by vigabatrin‐to‐nonstandard (3/10, 30%), hormonal‐to‐hormonal (4/22, 18%), and hormonal‐to‐nonstandard (1/30, 3.3%). Compared to the hormonal‐to‐vigabatrin group (reference), fewer infants had remission in the hormonal‐to‐nonstandard group (OR = .07, 95% confidence interval [CI] = .01–.53), and there was a trend toward fewer infants in the hormonal‐to‐hormonal group (OR = .43, 95% CI = .13–1.4, p = .17). Following initial hormonal treatment, the number needed to treat was three infants for one additional infant to have remission when treated with vigabatrin compared to nonstandard therapy as the second treatment. Significance This updated analysis with an expanded sample size provided power for additional subgroup analysis. Overall response rates were low, and at best only one third had remission after second treatment. Results support a clinical strategy of switching mechanism of action when selecting a second medication for epileptic spasms (i.e., use vigabatrin after hormonal therapy, or hormonal therapy after vigabatrin). Our findings also support the use of standard over nonstandard therapies.

Abstract Objective Wearable nonelectroencephalographic biosignal recordings captured from the wrist offer enormous potential for seizure monitoring. However, signal quality remains a challenging factor affecting data reliability. Models trained for seizure detection depend on the quality of recordings in peri‐ictal periods in performing a feature‐based separation of ictal periods from interictal periods. Thus, this study aims to investigate the effect of epileptic seizures on signal quality, ensuring accurate and reliable monitoring. Methods This study assesses the signal quality of wearable data during peri‐ictal phases of generalized tonic–clonic and focal to bilateral tonic–clonic seizures (TCS), focal motor seizures (FMS), and focal nonmotor seizures (FNMS). We evaluated accelerometer (ACC) activity and the signal quality of electrodermal activity (EDA) and blood volume pulse (BVP) data. Additionally, we analyzed the influence of peri‐ictal movements as assessed by ACC (ACC activity) on signal quality and examined intraictal subphases of focal to bilateral TCS. Results We analyzed 386 seizures from 111 individuals in three international epilepsy monitoring units. BVP signal quality and ACC activity levels differed between all seizure types. We found the largest decrease in BVP signal quality and increase in ACC activity when comparing the ictal phase to the pre‐ and postictal phases for TCS. Additionally, ACC activity was strongly negatively correlated with BVP signal quality for TCS and FMS, and weakly for FNMS. Intraictal analysis revealed that tonic and clonic subphases have the lowest BVP signal quality and the highest ACC activity. Significance Motor elements of seizures significantly impair BVP signal quality, but do not have significant effect on EDA signal quality, as assessed by wrist‐worn wearables. The results underscore the importance of signal quality assessment methods and careful selection of robust modalities to ensure reliable seizure detection. Future research is needed to explain whether seizure detection models' decisions are based on signal responses induced by physiological processes as opposed to artifacts.

AbstractObjectiveEpilepsy management employs self‐reported seizure diaries, despite evidence of seizure underreporting. Wearable and implantable seizure detection devices are now becoming more widely available. There are no clear guidelines about what levels of accuracy are sufficient. This study aimed to simulate clinical use cases and identify the necessary level of accuracy for each.MethodsUsing a realistic seizure simulator (CHOCOLATES), a ground truth was produced, which was then sampled to generate signals from simulated seizure detectors of various capabilities. Five use cases were evaluated: (1) randomized clinical trials (RCTs), (2) medication adjustment in clinic, (3) injury prevention, (4) sudden unexpected death in epilepsy (SUDEP) prevention, and (5) treatment of seizure clusters. We considered sensitivity (0%–100%), false alarm rate (FAR; 0–2/day), and device type (external wearable vs. implant) in each scenario.ResultsThe RCT case was efficient for a wide range of wearable parameters, though implantable devices were preferred. Lower accuracy wearables resulted in subtle changes in the distribution of patients enrolled in RCTs, and therefore higher sensitivity and lower FAR values were preferred. In the clinic case, a wide range of sensitivity, FAR, and device type yielded similar results. For injury prevention, SUDEP prevention, and seizure cluster treatment, each scenario required high sensitivity and yet was minimally influenced by FAR.SignificanceThe choice of use case is paramount in determining acceptable accuracy levels for a wearable seizure detection device. We offer simulation results for determining and verifying utility for specific use case and specific wearable parameters.

ObjectiveThe aim of this study was to determine whether selection of treatment for children with infantile spasms (IS) varies by race/ethnicity.MethodsThe prospective US National Infantile Spasms Consortium database includes children with IS treated from 2012 to 2018. We examined the relationship between race/ethnicity and receipt of standard IS therapy (prednisolone, adrenocorticotropic hormone, vigabatrin), adjusting for demographic and clinical variables using logistic regression. Our primary outcome was treatment course, which considered therapy prescribed for the first and, when needed, the second IS treatment together.ResultsOf 555 children, 324 (58%) were non‐Hispanic white, 55 (10%) non‐Hispanic Black, 24 (4%) non‐Hispanic Asian, 80 (14%) Hispanic, and 72 (13%) other/unknown. Most (398, 72%) received a standard treatment course. Insurance type, geographic location, history of prematurity, prior seizures, developmental delay or regression, abnormal head circumference, hypsarrhythmia, and IS etiologies were associated with standard therapy. In adjusted models, non‐Hispanic Black children had lower odds of receiving a standard treatment course compared with non‐Hispanic white children (odds ratio [OR], 0.42; 95% confidence interval [CI], 0.20–0.89; p = 0.02). Adjusted models also showed that children with public (vs. private) insurance had lower odds of receiving standard therapy for treatment 1 (OR, 0.42; CI, 0.21–0.84; p = 0.01).InterpretationNon‐Hispanic Black children were more often treated with non‐standard IS therapies than non‐Hispanic white children. Likewise, children with public (vs. private) insurance were less likely to receive standard therapies. Investigating drivers of inequities, and understanding the impact of racism on treatment decisions, are critical next steps to improve care for patients with IS. ANN NEUROL 2022;92:32–44

Abstract Objective This study was undertaken to evaluate benzodiazepine (BZD) administration patterns before transitioning to non‐BZD antiseizure medication (ASM) in pediatric patients with refractory convulsive status epilepticus (rSE). Methods This retrospective multicenter study in the United States and Canada used prospectively collected observational data from children admitted with rSE between 2011 and 2020. Outcome variables were the number of BZDs given before the first non‐BZD ASM, and the number of BZDs administered after 30 and 45 min from seizure onset and before escalating to non‐BZD ASM. Results We included 293 patients with a median (interquartile range) age of 3.8 (1.3–9.3) years. Thirty‐six percent received more than two BZDs before escalating, and the later the treatment initiation was after seizure onset, the less likely patients were to receive multiple BZD doses before transitioning (incidence rate ratio [IRR] = .998, 95% confidence interval [CI] = .997–.999 per minute, p = .01). Patients received BZDs beyond 30 and 45 min in 57.3% and 44.0% of cases, respectively. Patients with out‐of‐hospital seizure onset were more likely to receive more doses of BZDs beyond 30 min (IRR = 2.43, 95% CI = 1.73–3.46, p < .0001) and beyond 45 min (IRR = 3.75, 95% CI = 2.40–6.03, p < .0001) compared to patients with in‐hospital seizure onset. Intermittent SE was a risk factor for more BZDs administered beyond 45 min compared to continuous SE (IRR = 1.44, 95% CI = 1.01–2.06, p = .04). Forty‐seven percent of patients ( n = 94) with out‐of‐hospital onset did not receive treatment before hospital arrival. Among patients with out‐of‐hospital onset who received at least two BZDs before hospital arrival ( n = 54), 48.1% received additional BZDs at hospital arrival. Significance Failure to escalate from BZDs to non‐BZD ASMs occurs mainly in out‐of‐hospital rSE onset. Delays in the implementation of medical guidelines may be reduced by initiating treatment before hospital arrival and facilitating a transition to non‐BZD ASMs after two BZD doses during handoffs between prehospital and in‐hospital settings.

Purpose: Hypsarrhythmia is one of the major diagnostic and treatment response criteria in infantile spasms (IS). The clinical and electrophysiological effect of repository corticotropin injection treatment on IS was evaluated using electrophysiological biomarkers. Methods: Consecutive infants (<24 months) treated with repository corticotropin injection for IS were included in this retrospective descriptive study. Inclusion criteria were (1) clinical IS diagnosis, (2) repository corticotropin injection treatment, and (3) consecutive EEG recordings before and after repository corticotropin injection treatment. Patients with tuberous sclerosis complex were excluded. Response to treatment was defined as freedom from IS for at least 7 consecutive days during the treatment and resolution of hypsarrhythmia. The authors defined “relapse” as the recurrence of seizures after an initial response. Electrophysiological biomarker assessment included evaluation of semiautomatic spike counting algorithm, delta power, and delta coherence calculation during non-REM sleep EEG. Results: One hundred fifty patients (83 males; 55%; median age of IS onset: 5.9 months) with complete data were included, including 101 responders (67%, 71 with sustained response, and 30 relapses). Fifty patients (33%) with complete EEG data also underwent advanced EEG analysis. Baseline delta coherence was higher in sustained responders than in nonresponders or patients who relapsed. Greater decreases in semiautomatic spike counting algorithm, delta power, and delta coherence were found in sustained responders compared with nonresponders or patients who relapsed. Conclusions: Repository corticotropin injection treatment was associated with a 67% response rate in patients with IS. Computational biomarkers beyond hypsarrhythmia may provide additional information during IS treatment, such as early determination of treatment response and outcome assessment.

AbstractObjectiveThis study was undertaken to describe long‐term clinical and developmental outcomes in pediatric refractory status epilepticus (RSE) and identify factors associated with new neurological deficits after RSE.MethodsWe performed retrospective analyses of prospectively collected observational data from June 2011 to March 2020 on pediatric patients with RSE. We analyzed clinical outcomes from at least 30 days after RSE and, in a subanalysis, we assessed developmental outcomes and evaluated risk factors in previously normally developed patients.ResultsFollow‐up data on outcomes were available in 276 patients (56.5% males). The median (interquartile range [IQR]) follow‐up duration was 1.6 (.9–2.7) years. The in‐hospital mortality rate was 4% (16/403 patients), and 15 (5.4%) patients had died after hospital discharge. One hundred sixty‐six (62.9%) patients had subsequent unprovoked seizures, and 44 (16.9%) patients had a repeated RSE episode. Among 116 patients with normal development before RSE, 42 of 107 (39.3%) patients with available data had new neurological deficits (cognitive, behavioral, or motor). Patients with new deficits had longer median (IQR) electroclinical RSE duration than patients without new deficits (10.3 [2.1–134.5] h vs. 4 [1.6–16] h, p = .011, adjusted odds ratio = 1.003, 95% confidence interval = 1.0008–1.0069, p = .027). The proportion of patients with an unfavorable functional outcome (Glasgow Outcome Scale‐Extended score ≥ 4) was 22 of 90 (24.4%), and they were more likely to have received a continuous infusion.SignificanceAbout one third of patients without prior epilepsy developed recurrent unprovoked seizures after the RSE episode. In previously normally developing patients, 39% presented with new deficits during follow‐up, with longer electroclinical RSE duration as a predictor.