Three Patients of the Early Onset Epileptic Spasms without Hypsarrhythmia.

Epileptic spasms without hypsarrhythmia occur when patients do not display hypsarrhythmia on electroencephalogram (EEG) at the onset and throughout the clinical course. We report three patients of epileptic spasms in patients with early onset, all of whom experienced other types of seizures.We detail three patients (two boys and one girl) of epileptic spasms without hypsarrhythmia, occurring between 1 and 3 months of age, with no abnormalities detected on neurometabolic analysis and brain magnetic resonance imaging. Long-term video-EEG monitoring revealed epileptic spasms with focal onset seizures in two patients, and epileptic spasms followed by generalized tonic-clonic seizures in one patient. Hypsarrhythmia was never observed in repeated EEG examinations. Two patients achieved seizure freedom and improved development through treatment with topiramate alone or in combination with valproate, without requiring hormonal therapies or vigabatrin. The remaining patient achieved seizure freedom following administration of antiseizure medications, including topiramate, after a trial of adrenocorticotropic hormone therapy.We report the cases of three patients with early onset epileptic spasms without hypsarrhythmia. All patients achieved seizure freedom after topiramate treatment. Topiramate may be considered as a relatively effective antiseizure medication for early onset epileptic spasms without hypsarrhythmia.

Cavernous malformation located medially and deeply in the brain may be prone to false lateralization in cavernous malformation-associated epilepsy.

Background: Cavernous malformation (CM) is a well-known cause of epilepsy. Although the location of the CM is usually consistent with the side of seizure onset, some reports have described discrepancies between results from scalp electroencephalography (EEG) and CM location. This study investigated the prevalence and features of patients showing false lateralization (FL). Particularly, we tested the hypothesis that patients showing FL were more likely to have CM in medial and deep areas of the brain than in other areas. Methods: Patients diagnosed with CM-associated epilepsy in our institution between March 2009 and March 2023 were included in this retrospective analysis. We investigated the presence or absence of FL of interictal epileptiform discharges (IEDs) or ictal discharges against MRI findings or against the true focus as determined from surgical outcomes. We compared the FL group with the non-false-lateralization group (NFL group) to clarify features of CM-associated epilepsy patients showing FL. Results: Thirty-two epilepsy patients with CM were analyzed. The frequency of FL to MRI was 10.3% for IEDs and 7.7% for ictal discharges, while the frequency of FL to true focus after removal surgery was 10.5% for IEDs and 7.7% for ictal discharges. Regarding the FL of IEDs against MRI findings, the percentage of medial and deep lesions was significantly higher in the FL group (3/3, 100%) than in the NFL group (6/26, 23.1%; p = 0.023). No significant differences in age, sex, seizure type, or size of the CM were seen between groups. Conclusions: CM-associated epilepsy can also present with FL, particularly if the location of the CM is medial and deep. Caution may be needed in determining the area for resection based solely on scalp EEG findings.

Endovascular electroencephalography (eEEG) can detect the laterality of epileptogenic foci as accurately as subdural electrodes.

Background: Traditional brain activity monitoring via scalp electroencephalography (EEG) offers limited resolution and is susceptible to artifacts. Endovascular electroencephalography (eEEG) emerged in the 1990s. Despite early successes and potential for detecting epileptiform activity, eEEG has remained clinically unutilized. This study aimed to further test the capabilities of eEEG in detecting lateralized epileptic discharges in animal models. We hypothesized that eEEG would be able to detect lateralization. The purpose of this study was to measure epileptiform discharges with eEEG in animal models with lateralization in epileptogenicity. Materials and methods: We inserted eEEG electrodes into the transverse sinuses of three pigs, and subdural electrodes (SDs) on the surfaces of the left and right hemispheres. We induced epileptogenicity with penicillin in the left brain of pigs F00001 and F00003, and in the right brain of pig F00002. The resulting epileptiform discharges were measured by eEEG electrodes placed in the left and right transverse sinuses, and conducted comparisons with epileptiform discharges from SDs. We also had 12 neurological physicians interpret measurement results from eEEG alone and determine the side (left or right) of epileptogenicity. Results: Three pigs were evaluated for epileptiform discharge detection using eEEG: F00001 (7 months old, 14.0 kg), F00002 (8 months old, 15.6 kg), and F00003 (8 months old, 14.4 kg). The eEEG readings were compared with results from SDs, showing significant alignment across all subjects (p < 0.001). The sensitivity and positive predictive values (PPV) were as follows: F00001 had 0.93 and 0.96, F00002 had 0.99 and 1.00, and F00003 had 0.98 and 0.99. Even though one of the neurological physicians got all sides incorrect, all other assessments were correct. Upon post-experimental dissection, no abnormalities were observed in the brain tissue or in the vascular damage at the site where the eEEG was placed, based on pathological evaluation. Conclusion: With eEEG, lateralization can be determined with high sensitivity (>0.93) and PPV (>0.95) that appear equivalent to those of subdural EEG in the three pigs. This lateralization was also discernible by neurological physicians on visual inspection.

Prognostic factors for employment outcomes in patients with a history of childhood-onset drug-resistant epilepsy.

Objective: The employment outcomes of childhood-onset drug-resistant epilepsy (DRE) has not been studied enough. The aim of this retrospective cohort study is to investigate the employment outcomes of childhood-onset DRE in June 2022 and identify the risk factors associated with non-employment. Materials and methods: The sample consisted of 65 participants ≥18 years of age with a history of childhood-onset DRE. Fifty participants (77%) were salaried employees and 15 participants (23%) were non-employed. Clinical and psychosocial information were evaluated for calculating the relative risk (RR) of non-employment. Results: Regarding medical factors, lower IQ [RR, 0.645; 95% confidence interval (CI), 0.443-0.938; p = 0.022] was positively associated with employment. In contrast, age at follow-up (RR, 1.046; 95% CI, 1.009-1.085; p = 0.014); number of ASMs at follow-up (RR, 1.517; 95% CI, 1.081-2.129; p = 0.016); use of medications such as phenobarbital (RR, 3.111; 95% CI, 1.383-6.997; p = 0.006), levetiracetam (RR, 2.471; 95% CI, 1.056-5.782; p = 0.037), and topiramate (RR, 3.576; 95% CI, 1.644-7.780; p = 0.001) were negatively associated with employment. Regarding psychosocial factor, initial workplace at employment support facilities (RR, 0.241; 95% CI, 0.113-0.513; p < 0.001) was positively associated with employment. In contrast, complication of psychiatric disorder symptoms (RR, 6.833; 95% CI, 2.141-21.810; p = 0.001) was negatively associated with employment. Regarding educational factor, graduating schools of special needs education (RR, 0.148; 95% CI, 0.061-0.360; p < 0.001) was positively associated with employment. Conclusions: Specific medical, psychosocial, and educational factors may influence the employment outcomes of childhood-onset DRE. Paying attention to ASMs' side effects, adequately preventing the complications of psychiatric disorder symptoms, and providing an environment suitable for each patient condition would promote a fine working status for people with childhood-onset DRE.

Intravenous perampanel as an alternative to the oral formulations in Japanese patients with epilepsy.

OBJECTIVE: Perampanel is an oral anti-seizure medication, which is approved in Japan for focal-onset seizures, with/without focal to bilateral tonic-clonic seizures, as monotherapy/adjunctive therapy in patients aged 4 years and older. Treatment for generalized tonic-clonic seizures as adjunctive therapy in patients aged 12 years and older is approved as well. We evaluated the feasibility of intravenous (IV) administration of perampanel as an alternative to oral administration. METHODS: Study 240 (NCT03754582) was an uncontrolled, open-label study of IV perampanel, conducted in 21 Japanese patients with epilepsy who received a stable dose of 8-12 mg/day of oral perampanel. Patients received 30-minute IV infusions at equivalent daily doses of oral perampanel for 4 days, then were switched back to oral perampanel. Safety, tolerability, plasma concentration, and maintenance of efficacy throughout the transition between IV and oral dosing of perampanel were assessed. As supportive data, a subgroup analysis was also conducted using data from healthy Japanese subjects (n = 18) who were enrolled in Study 050 (NCT03376997) investigating the pharmacokinetics and safety of IV perampanel in healthy subjects who received an IV infusion (30-, 60-, or 90-minute) of perampanel 12 mg and a single oral administration of perampanel 12-mg tablet. RESULTS: In Study 240, the transition between 30-minute IV and oral perampanel dosing was associated with a ≤1.4-fold increase in the mean change in maximum observed concentration of perampanel. Seizure outcomes demonstrated no considerable changes in efficacy before, during, or after 30-minute IV dosing of perampanel. The safety profiles were similar between IV and oral formulations. In Study 050, the pharmacokinetics of 30- or 60-minute IV infusion of perampanel further support the interchangeability between oral and IV formulations in the Japanese subjects. SIGNIFICANCE: These results support that 30-minute IV perampanel may be a potential short-term alternative to oral formulations for patients with epilepsy.

Non-1st seizure was less severe than 1st seizure with non-urgent level among suspected seizures transferred by ambulance.

BACKGROUND: To prioritize emergency medical calls for ambulance transport for patients with suspected seizures, information about whether the event is their 1st or non-1st seizure is important. However, little is known about the difference between 1st and non-1st seizures in terms of severity. We hypothesized that patients transferred multiple times (≥2 times) would represent a milder scenario than patients on their first transfer. The purpose of this study was to compare patients with suspected seizures on 1st transfer by ambulance and patients who had been transferred ≥2 times. METHODS: We statistically compared severity of suspected seizures between two groups of patients with suspected seizures transferred between December 2014 and November 2019 (before the coronavirus disease 2019 pandemic) to our facility by ambulance for either the first time (1st Group) or at least the second time (Non-1st Group). Severity categories were defined as: Level 1 = life-threatening; Level 2 = emergent, needing admission to the intensive care unit; Level 3 = urgent, needing admission to a hospital general ward; Level 4 = less urgent, needing intervention but not hospitalization; and Level 5 = non-urgent, not needing intervention. RESULTS: Among 5996 patients with suspected seizures conveyed to the emergency department by ambulance a total of 14,263 times during the study period, 1222 times (8.6%) and 636 patients (11%) met the criteria. Severity grade of suspected seizures ranged from 1 to 5 (median, 4; interquartile range, 3-4) for the 1st Group and from 1 to 5 (median, 5; interquartile range, 4-5) for the Non-1st Group. Most severe grade ranged from 1 to 5 (median, 4; interquartile range, 4-5) for the Non-1st Group. Severity grade differed significantly between groups (p < 0.001, Mann-Whitney U-test). Uni- and multivariate logistic regression tests also suggested a significant difference (p < 0.001) in severity grades. CONCLUSION: In direct comparisons, grade of suspected seizure severity was lower in the Non-1st Group than in the 1st Group.

False lateralization of scalp EEG and semiology in cavernous malformation-associated temporal lobe epilepsy: A case report.

Background: Several cases of temporal lobe epilepsy (TLE) showing false lateralization of ictal scalp electroencephalography (EEG) have been reported. However, TLE with cavernous malformation indicating false lateralization of both ictal scalp EEG and semiology as in the present case is rare. The aim of this report is to call attention to avoiding overestimation of ictal scalp EEG findings in epilepsy patients with cavernous malformation. Case report: A 25-year-old man without any medical history suffered from seizures for a year despite appropriate anti-epileptic medication. Magnetic resonance imaging (MRI) revealed cavernous malformation in the left amygdala. The seizure type was brief impaired consciousness with left dystonic posturing, preceded by a sensation of blood rushing to the head. Long-term video EEG with scalp electrodes showed periodic sharp waves beginning from the right temporal area during seizures. Although both semiology and ictal scalp EEG indicated right TLE, intracranial EEG revealed the onset of low-voltage fast activity from the left hippocampus near the cavernous malformation. This patient therefore underwent removal of cavernous malformation and left amygdala, and achieved freedom from seizures postoperatively. Conclusion: We reinforce the importance of performing intracranial EEG for cavernous malformation-associated epilepsy when discrepancies between scalp EEG and MRI are evident.

Finger movement functions remain in the ipsilesional hemisphere and compensation by the contralesional hemisphere might not be expected after hemispherotomy -pre- and post-hemispherotomy evaluations in 8 cases.

BACKGROUND: We hypothesized that fine finger motor functions are controlled by the ipsilesional hemisphere, and that gross motor functions are compensated for by the contralesional hemisphere after brain injury in humans. The purpose of this study was to compare finger movements before and after hemispherotomy that defunctionated the ipsilesional hemisphere for patients with hemispherical lesions. METHODS: We statistically compared Brunnstrom stage of the fingers, arm (upper extremity), and leg (lower extremity) before and after hemispherotomy. Inclusion criteria for this study were: 1) hemispherotomy for hemispherical epilepsy; 2) a ≥ 6-month history of hemiparesis; 3) post-operative follow-up ≥ 6 months; 4) complete freedom from seizures without aura; and 5) application of our protocol for hemispherotomy. RESULTS: Among 36 patients who underwent multi-lobe disconnection surgeries, 8 patients (2 girls, 6 boys) met the study criteria. Mean age at surgery was 6.38 years (range, 2-12 years; median, 6 years; standard deviation, 3.5 years). Paresis of the fingers was significantly exacerbated (p = 0.011) compared to pre-operatively, whereas that of the upper limbs (p = 0.07) and lower limbs (p = 0.103) was not. CONCLUSION: Finger movement functions tend to remain in the ipsilesional hemisphere after brain injury, whereas gross motor movement functions such as those of the arms and legs are compensated for by the contralesional hemisphere in humans.

An integrated genetic analysis of epileptogenic brain malformed lesions.

Focal cortical dysplasia is the most common malformation during cortical development, sometimes excised by epilepsy surgery and often caused by somatic variants of the mTOR pathway genes. In this study, we performed a genetic analysis of epileptogenic brain malformed lesions from 64 patients with focal cortical dysplasia, hemimegalencephy, brain tumors, or hippocampal sclerosis. Targeted sequencing, whole-exome sequencing, and single nucleotide polymorphism microarray detected four germline and 35 somatic variants, comprising three copy number variants and 36 single nucleotide variants and indels in 37 patients. One of the somatic variants in focal cortical dysplasia type IIB was an in-frame deletion in MTOR, in which only gain-of-function missense variants have been reported. In focal cortical dysplasia type I, somatic variants of MAP2K1 and PTPN11 involved in the RAS/MAPK pathway were detected. The in-frame deletions of MTOR and MAP2K1 in this study resulted in the activation of the mTOR pathway in transiently transfected cells. In addition, the PTPN11 missense variant tended to elongate activation of the mTOR or RAS/MAPK pathway, depending on culture conditions. We demonstrate that epileptogenic brain malformed lesions except for focal cortical dysplasia type II arose from somatic variants of diverse genes but were eventually linked to the mTOR pathway.

Phase Lag Analysis Scalp Electroencephalography May Predict Seizure Frequencies in Patients with Childhood Epilepsy with Centrotemporal Spikes.

Background: Childhood epilepsy with centrotemporal spikes (CECTS) is the most common epilepsy syndrome in school-aged children. However, predictors for seizure frequency are yet to be clarified using the phase lag index (PLI) analyses. We investigated PLI of scalp electroencephalography data at onset to identify potential predictive markers for seizure times. Methods: We compared the PLIs of 13 patients with CECTS and 13 age- and sex-matched healthy controls. For the PLI analysis, we used resting-state electroencephalography data (excluding paroxysmal discharges), and analyzed the mean PLIs among all electrodes and between interest electrodes (C3, C4, P3, P4, T3, and T4) and other electrodes. Furthermore, we compared PLIs between CECTS and control data and analyzed the associations between PLIs and total seizure times in CECTS patients. Results: No differences were detected in clinical profiles or visual electroencephalography examinations between patients with CECTS and control participants. In patients with CECTS, the mean PLIs among all electrodes and toward interest electrodes were higher at the theta and alpha bands and lower at the delta and gamma bands than those in control participants. Additionally, the mean PLIs toward interest electrodes in the beta frequency band were negatively associated with seizure times (P = 0.02). Conclusion: The resting-state delta, theta, alpha, and gamma band PLIs might reflect an aberrant brain network in patients with CECTS. The resting-state PLI among the selected electrodes of interest in the beta frequency band may be a predictive marker of seizure times in patients with CECTS.

Unexplained Progressive Neurological Deficits after Corpus Callosotomy May Be Caused by Autoimmune Encephalitis: A Case of Suspected Postoperative Anti-NMDAR Encephalitis.

The main causes of anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis are ovarian teratoma and herpes simplex virus (HSV) encephalitis. We present a rare case of suspected anti-NMDAR encephalitis caused by corpus callosotomy (CC). An 18-year-old woman with Lennox-Gastaut syndrome underwent CC. Although left hemiplegic due to cerebral hemorrhage and impaired consciousness due to cerebral venous sinus thrombosis (CVST) appeared postoperatively, anticoagulant therapy quickly improved CVST and impaired consciousness. However, various unexplained symptoms such as insomnia, hallucination, impulsivity, impaired consciousness, and a new type of drug-resistant cluster seizures gradually developed over a 2-month period. Magnetic resonance imaging revealed the gradual extension of a hyperintense area from the right frontal lobe on fluid-attenuated inversion recovery images. Intravenous methylprednisolone pulse was initiated from postoperative day (POD) 74, followed by intravenous immunoglobulin (IVIg) therapy, although white blood cell counts were normal in all three cerebrospinal fluid (CSF) examinations. After IVIg therapy, the above unexplained symptoms promptly improved. On POD 103, antibodies against NMDAR were revealed in both the serum and CSF collected before these immunotherapies. The patient was transferred to a rehabilitation hospital due to residual left hemiplegia. Psychiatric symptoms and a new onset of drug-resistant seizures may be suggestive of postoperative anti-NMDAR encephalitis, even if CSF findings are mild.

Corpus Callosotomy: Editorial.

Since corpus callosotomy (CC) was first reported in 1940 [...].

Replacement of Valproic Acid with New Anti-Seizure Medications in Idiopathic Generalized Epilepsy.

Background: Little is known regarding the non-inferiority of new anti-seizure medications (ASMs) in terms of replacing valproic acid (VPA) in patients with idiopathic generalized epilepsy (IGE). We hypothesized that replacement of VPA with new ASMs would offer non-inferior or better control of seizure frequency. The purpose of this study was to compare epileptic seizure frequency between the subset of patients with IGE who were on VPA and the subset of patients with IGE who replaced VPA with new ASMs. Methods: Patients with IGE who were on or had been on VPA between January 2016 and March 2022 were divided into a group that replaced VPA with new ASMs (VPA-replace group) and a group that remained on VPA (VPA-continue group). We then compared the groups in terms of seizure frequency and myoclonus. Results: Of the 606 patients on VPA between January 2016 and March 2022, 156 patients with IGE were enrolled to this study (VPA-replace group, n = 68; VPA-continue group, n = 88). The VPA-replace group included significantly more females than the VPA-continue group (p < 0.001). The VPA-replace group also showed significantly higher seizure frequency before replacement (p < 0.001), but not after replacement (p = 0.074). Patients on monotherapy displayed improved seizure frequency with new ASMs (p < 0.001). Among the new ASMs, perampanel (PER) significantly improved seizure frequency (p = 0.002). Forty-two patients in the VPA-replace group who had myoclonus achieved significant improvements (p < 0.001). Among these, patients on PER monotherapy (p < 0.001) or PER + lamotrigine (0.016) showed significantly improved myoclonus scale scores. Conclusions: This study shows the non-inferiority of new ASMs compared to VPA, with better seizure control using new ASMs in subsets of patients with IGE on monotherapy.

A case of ALG11-congenital disorders of glycosylation diagnosed by post-mortem whole exome sequencing.

INTRODUCTION: Congenital disorders of glycosylation (CDG) are inherited inborn errors of metabolism due to abnormal protein and lipid glycosylation that present with multi-systemic manifestations. The heterogeneity of CDG poses a serious diagnostic challenge; therefore, whole-exome sequencing (WES), which plays an increasingly important role in the molecular diagnosis of CDG, is used for examining patients with CDG. CASE REPORT: We report the case of a two-month-old male patient who developed developmental and epileptic encephalopathy (DEE) with intractable seizures and microcephaly. EEG demonstrated a suppression-burst (S-B) pattern, and MRI showed delayed myelination and progressive atrophic changes. Although CDG was clinically suspected, serum transferrin isoelectric focusing analysis appeared to be normal. The patient died by six years of age. Postmortem WES performed approximately 20 years after the patient's death revealed homozygous variants in ALG11 (NM_001004127.3: c.935A > C, p.Glu312Ala), and the patient was diagnosed with ALG11-CDG. CONCLUSION: We present a case of the patient with ALG11-CDG diagnosed using post-mortem WES. The EEG revealed a S-B pattern that indicated severely drug-resistant DEE, which was associated with poor prognosis. If a CDG is suspected, WES should be considered.

Power and connectivity changes on electroencephalogram in postoperative cerebellar mutism.

INTRODUCTION: Cerebellar mutism syndrome is a debilitating postoperative neurological complication following posterior fossa surgery in children. It is characterized by a significant lack or loss of speech. Injury to the dentato-thalamo-cortical pathway is thought to be the main anatomical substrate of cerebellar mutism syndrome; however, few studies have investigated the physiological changes using computed electroencephalogram. CASE REPORT: Herein, we report a case of a nine-year-old girl who developed cerebellar mutism syndrome after excision of an ependymoma of the fourth ventricle and was followed up with evaluation of aphasia, gross motor function, and scalp electroencephalograms. Her language, dysmetria and gait ataxia gradually improved until day 605 after onset. Computed electroencephalogram analyses were performed for the relative power spectrum and connectivity at each frequency band. On the three electroencephalograms at days 109, 299, and 605 after onset, the relative power spectrum at the delta band transiently decreased and then increased, and the relative power spectrums at theta, beta, and gamma bands transiently increased and then decreased. Only the relative power spectrum in the alpha band continuously increased in the occipital area. Additionally, brain connectivity in the delta, beta, and gamma bands increased continuously. CONCLUSION: We report a case of cerebellar mutism syndrome with recovery of language, dysmetria and gait ataxia in 20 months. Electroencephalogram analyses indicated transient changes in the powers of brain activity and continuous improvements in connectivity during the long follow-up, reflecting the plasticity and remodeling of brain function after cerebellar mutism syndrome. Power and connectivity analyses for EEG might be a tool to investigate underlying pathophysiology of cerebellar mutism syndrome.

Stimulus-induced focal motor seizure in a pediatric patient with carbamazepine overdose.

INTRODUCTION: Carbamazepine (CBZ) is a common antiepileptic drug that may cause overdoses with seizures as a common neurological manifestation. In previous reports, patients with CBZ overdose exhibited stimulus-induced generalized clinical or electrical seizures. To date, no previous cases of focal motor seizures have been reported. CASE REPORT: We report the case of an 11-year-old girl with spontaneous and stimulus-induced clustering of focal motor seizures following CBZ overdose. The patient had been treated with CBZ (150 mg daily) for focal epilepsy since the age of six years. At the age of 11, she forgot to take a morning dose, took ten CBZ pills (CBZ 1000 mg) as compensation, and presented with generalized seizures. The patient arrived at the hospital in a coma. She demonstrated clustering of focal-to-bilateral tonic-clonic seizures induced by pain stimulus or spontaneously, with focal epileptiform discharges observed on EEG. Her CBZ blood concentration measured 40.4 µg/mL and she was diagnosed with CBZ overdose. The patient showed improvement without any specific treatment, and was later discharged without neurological sequelae. CONCLUSION: Previous cases of CBZ overdose with stimulus-induced generalized seizures resulted in death or required intensive care. Stimulus-induced focal seizures may indicate a favorable prognosis for CBZ overdose.

Omitting Hyperventilation in Electroencephalogram during the COVID-19 Pandemic May Reduce Interictal Epileptiform Discharges in Patients with Juvenile Myoclonic Epilepsy.

BACKGROUND: To prevent the spread of coronavirus disease 2019 (COVID-19), hyperventilation (HV) activation has been avoided in electroencephalograms (EEGs) since April 2020. The influence of omitting HV in EEG on epilepsy diagnosis remains uncertain for patients with epilepsies other than child absence epilepsy. We hypothesized that EEGs with HV would show more interictal epileptiform discharges (IEDs) than EEGs without HV in patients with juvenile myoclonic epilepsy (JME). METHODS: We reviewed the EEGs of seizure-free patients with JME who underwent EEG, both with and without HV, from January 2019 to October 2021, in our institution, and compared IEDs between EEG with and without HV. RESULTS: This study analyzed 23 JME patients. The IED-positive rate was significantly higher in EEG with HV (65.2%) than in EEG without HV (34.8%, p = 0.016). The mean ± standard deviation number of IEDs per minute was significantly larger during HV (1.61 ± 2.25 × 10-1) than during non-activation of both first EEG (0.57 ± 0.93 × 10-1, p = 0.039) and second EEG (0.39 ± 0.76 × 10-1, p = 0.009). CONCLUSIONS: In JME patients, performing HV during EEG may increase IEDs and appears to facilitate the accurate diagnosis of epilepsy.

Impact of COVID-19 pandemic on epilepsy care in Japan: A national-level multicenter retrospective cohort study.

OBJECTIVE: The impact of the coronavirus disease 2019 (COVID-19) pandemic on epilepsy care across Japan was investigated by conducting a multicenter retrospective cohort study. METHODS: This study included monthly data on the frequency of (1) visits by outpatients with epilepsy, (2) outpatient electroencephalography (EEG) studies, (3) telemedicine for epilepsy, (4) admissions for epilepsy, (5) EEG monitoring, and (6) epilepsy surgery in epilepsy centers and clinics across Japan between January 2019 and December 2020. We defined the primary outcome as epilepsy-center-specific monthly data divided by the 12-month average in 2019 for each facility. We determined whether the COVID-19 pandemic-related factors (such as year [2019 or 2020], COVID-19 cases in each prefecture in the previous month, and the state of emergency) were independently associated with these outcomes. RESULTS: In 2020, the frequency of outpatient EEG studies (-10.7%, p<0.001) and cases with telemedicine (+2,608%, p=0.031) were affected. The number of COVID-19 cases was an independent associated factor for epilepsy admission (-3.75*10-3 % per case, p<0.001) and EEG monitoring (-3.81*10-3 % per case, p = 0.004). Further, the state of emergency was an independent factor associated with outpatient with epilepsy (-11.9%, p<0.001), outpatient EEG (-32.3%, p<0.001), telemedicine for epilepsy (+12,915%, p<0.001), epilepsy admissions (-35.3%; p<0.001), EEG monitoring (-24.7%: p<0.001), and epilepsy surgery (-50.3%, p<0.001). SIGNIFICANCE: We demonstrated the significant impact that the COVID-19 pandemic had on epilepsy care. These results support those of previous studies and clarify the effect size of each pandemic-related factor on epilepsy care.

Endovascular Electroencephalogram Records Simultaneous Subdural Electrode-Detectable, Scalp Electrode-Undetectable Interictal Epileptiform Discharges.

INTRODUCTION: We hypothesized that an endovascular electroencephalogram (eEEG) can detect subdural electrode (SDE)-detectable, scalp EEG-undetectable epileptiform discharges. The purpose of this study is, therefore, to measure SDE-detectable, scalp EEG-undetectable epileptiform discharges by an eEEG on a pig. METHODS: A pig under general anesthesia was utilized to measure an artificially generated epileptic field by an eEEG that was able to be detected by an SDE, but not a scalp EEG as a primary outcome. We also compared the phase lag of each epileptiform discharge that was detected by the eEEG and SDE as a secondary outcome. RESULTS: The eEEG electrode detected 113 (97%) epileptiform discharges (97% sensitivity). Epileptiform discharges that were localized within the three contacts (contacts two, three and four), but not spread to other parts, were detected by the eEEG with a 92% sensitivity. The latency between peaks of the eEEG and right SDE earliest epileptiform discharge ranged from 0 to 48 ms (mean, 13.3 ms; median, 11 ms; standard deviation, 9.0 ms). CONCLUSION: In a pig, an eEEG could detect epileptiform discharges that an SDE could detect, but that a scalp EEG could not.