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Objective: Degree of indication for epilepsy surgery is determined by taking multiple factors into account. This study aimed to investigate the usefulness of the Specific Consistency Score (SCS), a proposed score for focal epilepsy to rate the indication for epilepsy focal resection. Methods: This retrospective cohort study included patients considered for resective epilepsy surgery in Kyoto University Hospital from 2011 to 2022. Plausible epileptic focus was tentatively defined. Cardinal findings were scored based on specificity and consistency with the estimated laterality and lobe. The total points represented SCS. The association between SCS and the following clinical parameters was assessed by univariate and multivariate analysis: (1) probability of undergoing resective epilepsy surgery, (2) good postoperative seizure outcome (Engel I and II or Engel I only), and (3) lobar concordance between the noninvasively estimated focus and intracranial electroencephalographic (EEG) recordings. Results: A total of 131 patients were evaluated. Univariate analysis revealed higher SCS in the (1) epilepsy surgery group (8.4 [95% confidence interval (CI) = 7.8–8.9] vs. 4.9 [95% CI = 4.3–5.5] points; p <.001), (2) good postoperative seizure outcome group (Engel I and II; 8.7 [95% CI = 8.2–9.3] vs. 6.4 [95% CI = 4.5–8.3] points; p =.008), and (3) patients whose focus defined by intracranial EEG matched the noninvasively estimated focus (8.3 [95% CI = 7.3–9.2] vs. 5.4 [95% CI = 3.5–7.3] points; p =.004). Multivariate analysis revealed areas under the curve of.843,.825, and.881 for Parameters 1, 2, and 3, respectively. Significance: SCS provides a reliable index of good indication for resective epilepsy surgery and can be easily available in many institutions not necessarily specializing in epilepsy. [ABSTRACT FROM AUTHOR]

• The number and amplitude of spikes decreased after 50-Hz stimulation of the seizure onset zone (SOZ). • Spike-related high-frequency activities (HFAs) also decreased and post-spike slow wave-related HFAs increased. • 50-Hz stimulation of the SOZ modulated cortical excitability toward less excitation and more inhibition. Using interictal epileptiform discharges (IEDs), consisting of spikes and post-spike slow waves (PSSs), and IED-related high-frequency activities (HFAs), we elucidated inhibitory effects of electrical cortical stimulation (ECS) on human epileptic foci. We recruited 8 patients with intractable focal epilepsy, and 50-Hz ECS was applied to the seizure-onset zone (SOZ) and non-SOZ. Before (5-min) and after (20-min) ECS, we evaluated the number of IED, the amplitudes of spikes and PSSs, spike-related HFA power, and PSS-related low gamma (30–50 Hz) activities. SOZ stimulation significantly decreased the number of IEDs and amplitude of spikes. Spike-related HFA power values in fast ripple (200–300 Hz) and ripple (80–150 Hz) bands were significantly suppressed only by SOZ stimulation in 4 and 3 patients, respectively. Among 4 patients with discrete PSSs, the amplitude ratio of spike/PSS decreased and the PSS-related low gamma activity power increased significantly in 2 patients and marginally in 1 patient. ECS potentially modulates cortical excitability by reducing excitation and increasing inhibition, and monitoring IED-related HFAs may help achieve the optimal effects of ECS. IED and IED-related HFAs are dynamic, potential surrogate markers for epileptic excitability during the interictal period. [ABSTRACT FROM AUTHOR]

Objective: Postseizure functional decline is a concern in poststroke epilepsy (PSE). However, data on electroencephalogram (EEG) markers associated with functional decline are scarce. Thus, we investigated whether periodic discharges (PDs) and their specific characteristics are associated with functional decline in patients with PSE. Methods: In this observational study, patients admitted with seizures of PSE and who had scalp EEGs were included. The association between the presence or absence of PDs and postseizure short‐term functional decline lasting 7 days after admission was investigated. In patients with PD, EEG markers were explored for risk stratification of short‐term functional decline, according to the American Clinical Neurophysiology Society's Standardized Critical Care EEG Terminology. The association between EEG markers and imaging findings and long‐term functional decline at discharge and 6 months after discharge, defined as an increase in the modified Rankin Scale score compared with the baseline, was evaluated. Results: In this study, 307 patients with PSE (median age = 75 years, range = 35–97 years, 64% males; hemorrhagic stroke, 47%) were enrolled. Compared with 247 patients without PDs, 60 patients with PDs were more likely to have short‐term functional decline (12 [20%] vs. 8 [3.2%], p <.001), with an adjusted odds ratio (OR) of 4.26 (95% confidence interval [CI] = 1.44–12.6, p =.009). Patients with superimposed fast‐activity PDs (PDs+F) had significantly more localized (rather than widespread) lesions (87% vs. 58%, p =.003), prolonged hyperperfusion (100% vs. 62%, p =.023), and a significantly higher risk of short‐term functional decline than those with PDs without fast activity (adjusted OR = 22.0, 95% CI = 1.87–259.4, p =.014). Six months after discharge, PDs+F were significantly associated with long‐term functional decline (adjusted OR = 4.21, 95% CI = 1.27–13.88, p =.018). Significance: In PSE, PDs+F are associated with sustained neuronal excitation and hyperperfusion, which may be a predictor of postseizure short‐ and long‐term functional decline. [ABSTRACT FROM AUTHOR]

Objective To assess the feasibility of multi-component electrocorticography (ECoG)-based mapping using “wide-spectrum, intrinsic-brain activities” for identifying the primary sensori-motor area (S1-M1). Methods We evaluated 14 epilepsy patients with 1514 subdural electrodes implantation covering the perirolandic cortices at Kyoto University Hospital between 2011 and 2016. We performed multi-component, ECoG-based mapping (band-pass filter, 0.016–300/600 Hz) involving combined analyses of the single components: movement-related cortical potential (<0.5–1 Hz), event-related synchronization (76–200 Hz), and event-related de-synchronization (8–24 Hz) to identify the S1-M1. The feasibility of multi-component mapping was assessed through comparisons with single-component mapping and electrical cortical stimulation (ECS). Results Among 54 functional areas evaluation, ECoG-based maps showed significantly higher rate of localization concordances with ECS maps when the three single-component maps were consistent than when those were inconsistent with each other (p < 0.001 in motor, and p = 0.02 in sensory mappings). Multi-component mapping revealed high sensitivity (89–90%) and specificity (94–97%) as compared with ECS. Conclusions Wide-spectrum, multi-component ECoG-based mapping is feasible, having high sensitivity/specificity relative to ECS. Significance This safe (non-stimulus) mapping strategy, alternative to ECS, would allow clinicians to rule in/out the possibility of brain function prior to resection surgery. [ABSTRACT FROM AUTHOR]

Objective: To assess whether post‐stroke epilepsy (PSE) is associated with neuroimaging findings of hemosiderin in a case–control study, and whether the addition of hemosiderin markers improves the risk stratification models of PSE. Methods: We performed a post‐hoc analysis of the PROgnosis of POST‐Stroke Epilepsy study enrolling PSE patients at National Cerebral and Cardiovascular Center, Osaka, Japan, from November 2014 to September 2019. PSE was diagnosed when one unprovoked seizure was experienced >7 days after the index stroke, as proposed by the International League Against Epilepsy. As controls, consecutive acute stroke patients with no history or absence of any late seizure or continuing antiseizure medications at least 3 months after stroke were retrospectively enrolled during the same study period. We examined cortical microbleeds and cortical superficial siderosis (cSS) using gradient‐echo T2*‐weighted images. A logistic regression model with ridge penalties was tuned using 10‐fold cross‐validation. We added the item of cSS to the existing models (SeLECT and CAVE) for predicting PSE and evaluated performance of new models. Results: The study included 180 patients with PSE (67 women; median age 74 years) and 1,183 controls (440 women; median age 74 years). The cSS frequency was higher in PSE than control groups (48.9% vs 5.7%, p < 0.0001). Compared with the existing models, the new models with cSS (SeLECT‐S and CAVE‐S) demonstrated significantly better predictive performance of PSE (net reclassification improvement 0.63 [p = 0.004] for SeLECT‐S and 0.88 [p = 0.001] for CAVE‐S at the testing data). Interpretation: Cortical superficial siderosis was associated with PSE, stratifying stroke survivors at high risk of PSE. ANN NEUROL 2023;93:357–370 [ABSTRACT FROM AUTHOR]

• Resection should include ictal single equivalent current dipole (SECD), interictal SECD and MRI lesion localization, when feasible. • Concordant ictal and interictal SECDs can be a favorable predictor of seizure freedom if the areas can be safely resected. • Among SECD, dynamic statistical parametric mapping, and linearly constrained minimum variance, SECD should be considered the first line of analysis for ictal MEG when the data is amenable to SECD source localization. The significance of ictal magnetoencephalography (MEG) is not well appreciated. We evaluated the relationships between ictal MEG, MRI, intracranial electroencephalography (ICEEG), surgery and postoperative seizure outcome. A total of 45 patients (46 cases) with ictal MEG who underwent epilepsy surgery was included. We examined the localization of each modality, surgical resection area and seizure freedom after surgery. Twenty-one (45.7%) out of 46 cases were seizure-free at more than 6 months follow-up. Median duration of postoperative follow-up was 16.5 months. The patients in whom ictal, interictal single equivalent current dipole (SECD) and MRI lesion localization were completely included in the resection had a higher chance of being seizure-free significantly (p < 0.05). Concordance between ictal and interictal SECD localizations was significantly associated with seizure-freedom. Concordance between MRI lesion and ictal SECD, concordance between ictal ICEEG and ictal and interictal SECD, as well as concordance between ictal ICEEG and MRI lesion were significantly associated with seizure freedom. Ictal MEG can contribute useful information for delineating the resection area in epilepsy surgery. Resection should include ictal, interictal SECDs and MRI lesion localization, when feasible. Concordant ictal and interictal SECDs on MEG can be a favorable predictor of seizure freedom. [ABSTRACT FROM AUTHOR]

Sleep-induced changes in human brain connectivity/excitability and their physiologic basis remain unclear, especially in the frontal lobe. We investigated sleep-induced connectivity and excitability changes in 11 patients who underwent chronic implantation of subdural electrodes for epilepsy surgery. Single-pulse electrical stimuli were directly injected to a part of the cortices, and cortico-cortical evoked potentials (CCEPs) and CCEP-related high-gamma activities (HGA: 100-200 Hz) were recorded from adjacent and remote cortices as proxies of effective connectivity and induced neuronal activity, respectively. HGA power during the initial CCEP component (N1) correlated with the N1 size itself across all states investigated. The degree of cortical connectivity and excitability changed during sleep depending on sleep stage, approximately showing dichotomy of awake vs. non-rapid eye movement (REM) [NREM] sleep. On the other hand, REM sleep partly had properties of both awake and NREM sleep, placing itself in the intermediate state between them. Compared with the awake state, single-pulse stimulation especially during NREM sleep induced increased connectivity (N1 size) and neuronal excitability (HGA increase at N1), which was immediately followed by intense inhibition (HGA decrease). The HGA decrease was temporally followed by the N2 peak (the second CCEP component), and then by HGA re-increase during sleep across all lobes. This HGA rebound or re-increase of neuronal synchrony was largest in the frontal lobe compared with the other lobes. These properties of sleep-induced changes of the cortex may be related to unconsciousness during sleep and frequent nocturnal seizures in frontal lobe epilepsy. Hum Brain Mapp, 2015. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Objective: Motivated by the challenges raised by diagnosing poststroke epilepsy (PSE), especially in nonmotor onset seizure (non‐MOS), we aimed to investigate the features of non‐MOS, including seizure sequences, patient characteristics, and electrophysiological and imaging findings in PSE. Methods: This observational cohort study enrolled patients with PSE whose seizure onset was witnessed. According to the International League Against Epilepsy (ILAE) 2017 seizure classification, we classified seizure‐onset symptoms into the non‐MOS and MOS groups. We compared the different clinical characteristics between the two groups. Results: Between 2011 and 2018, we enrolled 225 patients with PSE (median age, 75 years), consisting of 97 (43%) with non‐MOS and 128 (57%) with MOS. Overall, 65 (67%) of the patients without MOS had no subsequent convulsions. Multivariable logistic regression analysis showed significant associations of non‐MOS with absence of poststroke hemiparesis (adjusted odds ratio [OR], 1.88; 95% confidence interval [CI], 1.03–3.42), frontal stroke lobe lesions (OR, 2.11; 95% CI, 1.14–3.91), and putaminal stroke lesions (OR, 2.51; 95% CI, 1.22–5.18) as negative indicators. Postictal single‐photon emission computed tomography (SPECT) detected prolonged hyperperfusion in the temporal lobe more frequently in the non‐MOS than in the MOS group (48% vs 31%; p =.02). The detection rate was higher than spikes/sharp waves in scalp electroencephalography, both in the non‐MOS group (72% vs 33%; p <.001) and the MOS group (68% vs 29%; p <.001). Significance: This study provides the clinical features of non‐MOS in patients with PSE. Compared with the patients with MOS, patients with non‐MOS showed less likely subsequent convulsive seizures, highlighting the clinical challenges. Postictal perfusion imaging and negative indicators of the non‐MOS type may help diagnose and stratify PSE. [ABSTRACT FROM AUTHOR]

Summary The clinical anticipation in Japanese benign adult familial myoclonus epilepsy (BAFME), defined as earlier onset age of either cortical tremor or generalized seizures or new appearance of those symptoms in the next generation, remains unknown. The onset age and the degree of both cortical tremor and generalized seizures were investigated in nine patients of four BAFME families (mean age: 46.6 ± 18.7 years). Clinical anticipation in the onset age of cortical tremor or generalized seizures was observed in three families, and generalized seizures newly appeared in the next generation in those two families and in another family. Clinical anticipation was observed in four families, which suggests the clinical progression over generation in Japanese BAFME families. [ABSTRACT FROM AUTHOR]

Background: Atrial natriuretic peptide (ANP) plays important roles in the regulation of cardiovascular and renal homeostasis. Furthermore, several studies have shown that ANP may have anti-inflammatory activities. We hypothesized that ANP may alleviate cardiovascular and/or metabolic disorders in rats with lipopolysaccharide (LPS)-induced endotoxemia. Methods: In rats anesthetized with pentobarbital, LPS was injected and ANP was continuously infused at 0.15 μg/kg/min. Mean arterial pressure and pulse rate were monitored hourly, and arterial blood gases were analyzed before LPS injection and at 1, 4, and 6 hours after LPS injection. The expression in the rat left ventricle of mRNAs encoding nitric oxide synthase 2 and 3 (iNOS, eNOS), heme oxygenase 1 and 2 (HO-1, 2), tumor necrosis factor α (TNFα), and interleukin (IL)-1β was measured with the real-time reverse transcriptase-polymerase chain reaction. Results: LPS increased the expression of TNFα, IL-1β, iNOS, and HO-1, which was inhibited by infusion of ANP. Furthermore, the LPS-induced decrease in mean arterial pressure was attenuated, and the acid-base imbalance caused by increased lactate production was improved 6 hours after the administration of ANP. Conclusions: Our results suggest that continuous infusion of ANP counteracts the cardiovascular and metabolic disorders associated with endotoxemia, possibly via anti-inflammatory mechanisms. [ABSTRACT FROM AUTHOR]

Competition is under way around the world to develop fuel cell vehicles fitted with a polymer electrolyte membrane (PEM) fuel cell system. In this research, a methanol steam reforming system has been developed for application to a reformer-based fuel cell system. A Pd hydrogen permeation membrane and a heat exchanger type reformer have been applied to a 30-kW system to achieve higher efficiency. As a result, the characteristics of the Pd membrane and steam reformer were made clear, and the possibility of using this system as an automotive power plant was investigated. This research was conducted under a project sponsored by The New Energy and Industrial Technology Development Organization (NEDO). [ABSTRACT FROM AUTHOR]

Objective: To determine whether brain connectivity differs between focal cortical dysplasia (FCD) types I and II. Methods: We compared cortico‐cortical evoked potentials (CCEPs) as measures of effective brain connectivity in 25 FCD patients with drug‐resistant focal epilepsy who underwent intracranial evaluation with stereo‐electroencephalography (SEEG). We analyzed the amplitude and latency of CCEP responses following ictal‐onset single‐pulse electrical stimulation (iSPES). Results: In comparison to FCD type II, patients with type I demonstrated significantly larger responses in the electrodes near the ictal‐onset zone (<50 mm). These findings persisted when controlling for the location of the epileptogenic zone, as noted in patients with temporal lobe epilepsies, as well as controlling for seizure type, as noted in patients with focal to bilateral tonic‐clonic seizures (FBTCS). In type II, the root mean square (RMS) of CCEP responses dropped substantially from the early segment (10–60 ms) to the middle and late segments (60–600 ms). The middle and late CCEP latency segments showed the largest differences between FCD types I and II. Significance: Focal cortical dysplasia type I may have a greater degree of cortical hyperexcitability as compared with FCD type II. In addition, FCD type II displays a more restrictive area of hyperexcitability in both temporal and spatial domains. In patients with FBTCS and type I FCD, the increased amplitudes of RMS in the middle and late CCEP periods appear consistent with the cortico‐thalamo‐cortical network involvement of FBTCS. The notable differences in degree and extent of hyperexcitability may contribute to the different postsurgical seizure outcomes noted between these two pathological substrates. [ABSTRACT FROM AUTHOR]

Background: Benign adult familial myoclonus epilepsy (BAFME) is one of the diseases that cause cortical myoclonus (CM) with giant somatosensory evoked potentials (SEPs). There are no useful diagnostic biomarkers differentiating BAFME from other CM diseases. Objective: To establish reliable biomarkers including high‐frequency oscillations (HFOs) with giant SEPs for the diagnosis of BAFME. Methods: This retrospective case study included 49 consecutive CM patients (16 BAFME and 33 other CM patients) who exhibited giant P25 or N35 SEPs. SEPs were processed by a band‐pass filter of 400–1000 Hz to analyze HFOs. Clinical and SEP findings were compared between (1) BAFME and other CM groups and (2) patients with presence and absence of P25‐HFOs (HFOs superimposed on giant P25). The diagnostic power of each factor for BAFME was calculated. Results: All 16 BAFME patients showed SEP P25‐HFOs with significantly higher occurrence (P < 0.0001) compared with that of other CM groups. The presence of P25‐HFOs significantly correlated with a BAFME diagnosis (P < 0.0001) and high SEP P25 and N35 amplitudes (P = 0.01 and P < 0.0001, respectively). BAFME was reliably diagnosed using P25‐HFOs with high sensitivity (100%), specificity (87.9%), positive predictive value (80%), and negative predictive value (100%), demonstrating its superiority as a diagnostic factor compared to other factors. Conclusions: P25‐HFOs with giant SEPs is a potential biomarker for BAFME diagnosis. P25‐HFOs may reflect cortical hyperexcitability partly due to paroxysmal depolarizing shifts in epileptic neuronal activities and higher degrees of rhythmic tremulousness than those in ordinary CM. © 2021 International Parkinson and Movement Disorder Society [ABSTRACT FROM AUTHOR]

Background and purpose: The management of post‐stroke epilepsy (PSE) should ideally include prevention of both seizure and adverse effects; however, an optimal antiseizure medications (ASM) regimen has yet been established. The purpose of this study is to assess seizure recurrence, retention, and tolerability of older‐generation and newer‐generation ASM for PSE. Methods: This prospective multicenter cohort study (PROgnosis of Post‐Stroke Epilepsy [PROPOSE] study) was conducted from November 2014 to September 2019 at eight hospitals. A total of 372 patients admitted and treated with ASM at discharge were recruited. Due to the non‐interventional nature of the study, ASM regimen was not adjusted and followed standard hospital practices. The primary outcome was seizure recurrence in patients receiving older‐generation and newer‐generation ASM. The secondary outcomes were the retention and tolerability of ASM regimens. Results: Of the 372 PSE patients with ASM at discharge (median [IQR] age, 73 [64–81] years; 139 women [37.4%]), 36 were treated with older‐generation, 286 with newer‐generation, and 50 with mixed‐generation ASM. In older‐ and newer‐generation ASM groups (n = 322), 98 patients (30.4%) had recurrent seizures and 91 patients (28.3%) switched ASM regimen during the follow‐up (371 [347–420] days). Seizure recurrence was lower in newer‐generation, compared with the older‐generation, ASM (hazard ratio [HR], 0.42, 95%CI 0.27–0.70; p =.0013). ASM regimen withdrawal and change of dosages were lower in newer‐generation ASM (HR, 0.34, 95% CI 0.21–0.56, p <.0001). Conclusions: Newer‐generation ASM possess advantages over older‐generation ASM for secondary prophylaxis of post‐stroke seizures in clinical practice. [ABSTRACT FROM AUTHOR]

Diagnosis of post-stroke epilepsy is often challenging because of a low incidence of epileptiform abnormalities on electroencephalography (EEG). Hence, this study evaluated whether postictal subtraction single-photon emission computed tomography (SPECT) could visualize epileptic activity and act as a diagnostic modality in post-stroke epilepsy. Fifty post-stroke epilepsy patients, who had undergone Tc-99m-ECD SPECT twice (postictal and interictal), were enrolled. The postictal hyperperfusion area was identified by subtraction (postictal–interictal) SPECT and classified into two distribution types: superficial or deep-seated. Laterality and distribution of postictal hyperperfusion on subtraction SPECT were compared with stroke lesions, seizure symptoms, and epileptiform EEG findings. Forty-three of the 50 patients (86%) had hyperperfusion on subtraction SPECT and 26 (52%) had epileptiform EEG findings. Subtraction SPECT showed prolonged postictal hyperperfusion despite the relatively long interval between seizure end and postictal SPECT (median: 19.1 h, range: 2.2–112.5 h). The laterality of the hyperperfusion area had a high concordance rate with the laterality of stroke lesions (97.7%), seizure symptoms (91.9%), and epileptiform EEG findings (100%). Scalp EEG identified epileptiform activity more frequently in superficial type of SPECT, but less frequently in deep-seated type (both, P = 0.03). Postictal SPECT can be complementary to scalp EEG in endorsing the diagnosis and location of post-stroke epilepsy. [ABSTRACT FROM AUTHOR]

• Low dose of perampanel (PER) is tolerable and effective to ameliorate refractory cortical myoclonus. • PER suppresses and disperses paroxysmal depolarization shifts directly on the postsynaptic neurons. • This action was reflected by temporal dispersion in giant SEPs (a potential clinical biomarker). To elucidate the effects of perampanel (PER) on refractory cortical myoclonus for dose, etiology and somatosensory-evoked potential (SEP) findings. We examined 18 epilepsy patients with seizure and cortical myoclonus. Based on data accumulated before and after PER treatment, correlations among clinical scores in myoclonus and activities of daily life (ADL); early cortical components of SEP; and PER blood concentration, were analyzed. PER (mean dose: 3.2 ± 2.1 mg/day) significantly improved seizures, myoclonus and ADL and significantly decreased the amplitude of and prolonged latency of giant SEP components. The degree of P25 and N33 prolongations (23.8 ± 1.6 to 24.7 ± 1.7 ms and 32.1 ± 4.0 to 33.7 ± 3.4 ms) were significantly correlated with improved ADL score (p = 0.019 and p = 0.025) and blood PER concentration (p = 0.011 and p = 0.025), respectively. Low-dose PER markedly improved myoclonus and ADL in patients with refractory cortical myoclonus. Our results suggest that SEP, particularly P25 latency, can be used as a potential biomarker for assessing the objective effects of PER on intractable cortical myoclonus. In this study, PER lessened the degree of synchronized discharges in the postsynaptic neurons in the primary motor cortex. [ABSTRACT FROM AUTHOR]