Uncovering spatiotemporal dynamics of the corticothalamic network at ictal onset.

OBJECTIVE: Although the clinical efficacy of deep brain stimulation targeting the anterior nucleus (AN) and centromedian nucleus (CM) of the thalamus has been actively investigated for the treatment of medication-resistant epilepsy, few studies have investigated dynamic ictal changes in corticothalamic connectivity in human electroencephalographic (EEG) recording. This study aims to establish the complex spatiotemporal dynamics of the ictal corticothalamic network associated with various seizure foci. METHODS: We analyzed 10 patients (aged 2.7-28.1 years) with medication-resistant focal epilepsy who underwent stereotactic EEG evaluation with thalamic sampling. We examined both undirected and directed connectivity, incorporating coherence and spectral Granger causality analysis (GCA) between the diverse seizure foci and thalamic nuclei (AN and CM) at ictal onset. RESULTS: In our analysis of 36 seizures, coherence between seizure onset and thalamic nuclei increased across all frequencies, especially in slower bands (delta, theta, alpha). GCA showed increased information flow from seizure onset to the thalamus across all frequency bands, but outflows from the thalamus were mainly in slower frequencies, particularly delta. In the subgroup analysis based on various seizure foci, the delta coherence showed a more pronounced increase at CM than at AN during frontal lobe seizures. Conversely, in limbic seizures, the delta coherence increase was greater at AN compared to CM. SIGNIFICANCE: It appears that the delta frequency plays a pivotal role in modulating the corticothalamic network during seizures. Our results underscore the significance of comprehending the spatiotemporal dynamics of the corticothalamic network at ictal onset, and this knowledge could guide personalized responsive neuromodulation treatment strategies.

High mobility group box 1 and angiogenetic growth factor levels in children with central nerve system infections.

INTRODUCTION: To clarify the pathology of children with acute encephalopathy and other neurological disorders, the involvement of high-mobility group box 1 (HMGB1), which is a representative of danger-associated molecular patterns, and angiogenesis-related growth factors were investigated. PATIENTS AND METHODS: Participants were 12 children with acute encephalopathy (influenza, rotavirus, and others), 7 with bacterial meningitis, and 6 with epilepsy disease (West syndrome). Twenty-four patients with non-central nervous system (CNS) infections as a control group were admitted to our hospital. We examined the levels of HMGB1, platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), and other cytokines in the serum and cerebrospinal fluid (CSF) of the subjects. RESULTS: Serum and CSF HMGB1 levels were significantly higher in the encephalopathy and meningitis groups than in the West syndrome and control groups. CSF HMGB1 levels correlated with those of interleukin-6 and -8. CSF HMGB1 and VEGF levels were correlated, and PDGF showed a positive relationship. CONCLUSION: HMGB1 and angiogenesis-related growth factors appear to play pivotal roles in the pathophysiology of CNS infections.

Towards a Treatment for Neuroinflammation in Epilepsy: Interleukin-1 Receptor Antagonist, Anakinra, as a Potential Treatment in Intractable Epilepsy.

Febrile Infection-Related Epilepsy Syndrome (FIRES) is a unique catastrophic epilepsy syndrome, and the development of drug-resistant epilepsy (DRE) is inevitable. Recently, anakinra, an interleukin-1 receptor antagonist (IL-1RA), has been increasingly used to treat DRE due to its potent anticonvulsant activity. We here summarized its effects in 38 patients (32 patients with FIRES and six with DRE). Of the 22 patients with FIRES, 16 (73%) had at least short-term seizure control 1 week after starting anakinra, while the remaining six suspected anakinra-refractory cases were male and had poor prognoses. Due to the small sample size, an explanation for anakinra refractoriness was not evident. In all DRE patients, seizures disappeared or improved, and cognitive function improved in five of the six patients following treatment. Patients showed no serious side effects, although drug reactions with eosinophilia and systemic symptoms, cytopenia, and infections were observed. Thus, anakinra has led to a marked improvement in some cases, and functional deficiency of IL-1RA was indicated, supporting a direct mechanism for its therapeutic effect. This review first discusses the effectiveness of anakinra for intractable epileptic syndromes. Anakinra could become a new tool for intractable epilepsy treatment. However, it does not currently have a solid evidence base.

Links between Immune Cells from the Periphery and the Brain in the Pathogenesis of Epilepsy: A Narrative Review.

Accumulating evidence has demonstrated that the pathogenesis of epilepsy is linked to neuroinflammation and cerebrovascular dysfunction. Peripheral immune cell invasion into the brain, along with these responses, is implicitly involved in epilepsy. This review explored the current literature on the association between the peripheral and central nervous systems in the pathogenesis of epilepsy, and highlights novel research directions for therapeutic interventions targeting these reactions. Previous experimental and human studies have demonstrated the activation of the innate and adaptive immune responses in the brain. The time required for monocytes (responsible for innate immunity) and T cells (involved in acquired immunity) to invade the central nervous system after a seizure varies. Moreover, the time between the leakage associated with blood-brain barrier (BBB) failure and the infiltration of these cells varies. This suggests that cell infiltration is not merely a secondary disruptive event associated with BBB failure, but also a non-disruptive event facilitated by various mediators produced by the neurovascular unit consisting of neurons, perivascular astrocytes, microglia, pericytes, and endothelial cells. Moreover, genetic manipulation has enabled the differentiation between peripheral monocytes and resident microglia, which was previously considered difficult. Thus, the evidence suggests that peripheral monocytes may contribute to the pathogenesis of seizures.

Role of Neuroinflammation and Blood-Brain Barrier Permutability on Migraine.

Currently, migraine is treated mainly by targeting calcitonin gene-related peptides, although the efficacy of this method is limited and new treatment strategies are desired. Neuroinflammation has been implicated in the pathogenesis of migraine. In patients with migraine, peripheral levels of pro-inflammatory cytokines, such as interleukin-1ß (IL-1ß) and tumor necrosis factor-α, are known to be increased. Additionally, animal models of headache have demonstrated that immunological responses associated with cytokines are involved in the pathogenesis of migraine. Furthermore, these inflammatory mediators might alter the function of tight junctions in brain vascular endothelial cells in animal models, but not in human patients. Based on clinical findings showing elevated IL-1ß, and experimental findings involving IL-1ß and both the peripheral trigeminal ganglion and central trigeminal vascular pathways, regulation of the Il-1ß/IL-1 receptor type 1 axis might lead to new treatments for migraine. However, the integrity of the blood-brain barrier is not expected to be affected during attacks in patients with migraine.

Novel compound heterozygous DPH1 mutations in a patient with the unique clinical features of airway obstruction and external genital abnormalities.

The diphthamide biosynthesis 1 (DPH1) gene encodes one of the essential components of the enzyme catalyzing the first step of diphthamide formation on eukaryotic elongation factor 2 (EEF2). Diphthamide is the posttranslationally modified histidine residue on EEF2 that promotes protein chain elongation in the ribosome. DPH1 defects result in a failure of protein synthesis involving EEF2, leading to growth defects, embryonic lethality, and cell death. In humans, DPH1 mutations cause developmental delay with a short stature, dysmorphic features, and sparse hair, and are inherited in an autosomal recessive manner (MIM#616901). To date, only two homozygous missense mutations in DPH1 (c.17T>A, p.Met6Lys and c.701T>C, p.Leu234Pro) have been reported. We used WES to identify novel compound heterozygous mutations in DPH1 (c.289delG, p.Glu97Lysfs*8 and c.491T>C, p.Leu164Pro) in a patient from a nonconsanguineous family presenting with intellectual disability, a short stature, craniofacial abnormalities, and external genital abnormalities. The clinical phenotype of all patients with DPH1 mutations, including the current patient, revealed core features, although the external genital anomaly was newly recognized in our case.

Pathological analysis of children with childhood central nervous system infection based on changes in chemokines and interleukin-17 family cytokines in cerebrospinal fluid.

BACKGROUND: In this study, the pathologies of acute meningitis and encephalopathy were investigated, and biomarkers useful as prognostic indices were searched for. METHODS: The subjects were 31 children with meningitis, 30 with encephalopathy, and 12 with convulsions following gastroenteritis. Control group consisted of 24 children with non-central nervous system infection. Cerebrospinal fluid cytokine analysis was performed. RESULTS: Chemokines significantly increased in the bacterial meningitis group compared with those in viral meningitis and encephalopathy groups. On comparison of interleukin(IL)-17, it increased in cases with status epilepticus in influenza-associated encephalopathy group. In the rotavirus encephalopathy and convulsions following gastroenteritis groups, IL-17 particularly increased in the convulsions following gastroenteritis group. IL-8 increased in all cases irrespective of the causative virus. CONCLUSIONS: In the encephalopathy group, IL-8 may serve as a neurological prognostic index. IL-17 was increased in the convulsions following gastroenteritis group, particularly in cases with status epilepticus, suggesting its involvement as a convulsion-related factor.

Vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) levels in the cerebrospinal fluid of children with influenza-associated encephalopathy.

INTRODUCTION: To search for an index of neurologic prognosis of children with influenza-associated encephalopathy (IAE), involvement of angiogenesis-related growth factors in the pathology was investigated. PATIENTS AND METHODS: The subjects were 11 IAE patients, 6 patients with bacterial meningitis (BM), and 24 patients with non-central nervous system infection as a control group admitted to our hospital. The correlation between the vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) levels in cerebrospinal fluid and the relationship with an index of inflammatory marker, interleukin (IL)-6, were investigated. Using the Pediatric Cerebral Performance Categories (PCPC) score as a prognostic indicator, we evaluated the association between the biomarkers and neurologic prognosis. RESULT: PDGF significantly increased in the IAE group compared with that in the BM group. Cerebrospinal fluid VEGF and PDGF increased in all IAE and BM patients compared with that in the control group, and VEGF and PDGF were positively correlated in the 2 groups. No correlation was found between the cerebrospinal fluid VEGF and PDGF levels and IL-6 level in the IAE group, whereas a correlation was found in the BM group. All these factors increased in patients with poor neurologic prognosis. DISCUSSION: It is possible that the disease state of IAE can be evaluated based on vascular endothelial disorder-related markers.

Examination of neurological prognostic markers in patients with respiratory syncytial virus-associated encephalopathy.

No biomarker has been established as a prognostic indicator of acute encephalopathy associated with various etiological factors. In this study, we examined useful prognostic biomarkers in patients with acute encephalopathy associated with respiratory syncytial virus (RSV) infection. The subjects were 11 children with RSV-associated encephalopathy admitted to our hospital. We measured the levels of interleukin (IL)-6, brain-derived neurotrophic factor (BDNF) and nitrogen oxide (NO)x in cerebrospinal fluid collected on the day of admission. Using the pediatric cerebral performance categories (PCPC) score as a prognostic indicator, we evaluated the association between the biomarkers and neurologic prognosis. Concerning neurologic prognosis, sequelae were noted in more than 50% of the subjects. There was no association between prognosis and age/sex. Increases in the levels of all biomarkers were observed in all subjects. IL-6 and BDNF levels were correlated with PCPC score, but not with NOx. Of the biomarkers investigated, the IL-6 and BDNF levels in cerebrospinal fluid were shown to be correlated with neurologic prognosis. Because many patients with this disease had severe sequelae, assessment should be conducted by early evaluation of the biomarkers examined in this study with respect to the clinical course.

Single-Photon Emission Computed Tomography Is an Ambiguous Imaging Method on Initial Diagnosis for Acute Encephalopathy.

The distinction between acute encephalopathy (AE) and convulsive disorders with pyrexia may be problematic. We analyzed the clinical and laboratory features in 127 children who were admitted for suspected AE. They were categorized into (1) definite acute encephalopathy group (DAEG; n = 17, abnormal findings on electroencephalography [EEG], magnetic resonance imaging, or single-photon emission computed tomography [SPECT] with prolonged impaired consciousness), (2) probable acute encephalopathy group (PAEG; n = 21, abnormal findings without prolonged impaired consciousness), and (3) nonacute encephalopathy group (NAEG; n = 89). Cerebrospinal fluid interleukin-6 (CSF IL-6), and serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and creatine phosphokinase levels were significantly higher in DAEG compared with NAEG but not PAEG. No significant differences were observed between DAEG and PAEG except for serum creatinine levels. In PAEG, an area of hypoperfusion was observed on SPECT images of nine patients with normal CSF IL-6 levels. AE was suspected in two PAEG patients who exhibited high CSF IL-6 levels and abnormal EEG findings without abnormal SPECT findings. All seven patients with severe neurological sequelae were categorized to DAEG. CSF IL-6 and serum AST, ALT, and creatine kinase levels may be valid predictors of typical AE; prolonged impaired consciousness is an important sign of AE. However, SPECT may not be suitable for initial diagnosis of AE.

Acute suppurative oligoarthritis and osteomyelitis: a differential diagnosis that overlaps with acute rheumatic fever.

BACKGROUND: Acute rheumatic fever (ARF) is an illness caused by group A streptococcus (GAS) infection, and remains the leading cause of acquired heart disease in worldwide. Distinguishing between ARF and septic arthritis may be difficult. This report describes a case of suppurative arthritis overlapping with ARF. CASE PRESENTATION: A 4-year-old, previously healthy boy presented with fever and left leg pain. The level of anti-streptolysin O (ASO) was elevated. His throat swab cultures grew GAS, but none were detected in his synovial fluid. Magnetic resonance imaging revealed suspected arthritis and osteomyelitis. The patient was treated for septic arthritis, but was subsequently diagnosed with ARF, after the development of carditis. CONCLUSION: The clinical and laboratory features of ARF and suppurative arthritis demonstrate substantial overlap. Patients with an elevated ASO should undergo a careful cardiac examination for carditis associated with ARF by an echocardiogram.

Brain-derived neurotrophic factor and interleukin-6 levels in the serum and cerebrospinal fluid of children with viral infection-induced encephalopathy.

We investigated changes in the brain-derived neurotrophic factor (BDNF) and interleukin (IL)-6 levels in pediatric patients with central nervous system (CNS) infections, particularly viral infection-induced encephalopathy. Over a 5-year study period, 24 children hospitalized with encephalopathy were grouped based on their acute encephalopathy type (the excitotoxicity, cytokine storm, and metabolic error types). Children without CNS infections served as controls. In serum and cerebrospinal fluid (CSF) samples, BDNF and IL-6 levels were increased in all encephalopathy groups, and significant increases were noted in the influenza-associated and cytokine storm encephalopathy groups. Children with sequelae showed higher BDNF and IL-6 levels than those without sequelae. In pediatric patients, changes in serum and CSF BDNF and IL-6 levels may serve as a prognostic index of CNS infections, particularly for the diagnosis of encephalopathy and differentiation of encephalopathy types.

Computational EEG attributes predict response to therapy for epileptic spasms.

OBJECTIVE: We set out to evaluate whether response to treatment for epileptic spasms is associated with specific candidate computational EEG biomarkers, independent of clinical attributes. METHODS: We identified 50 children with epileptic spasms, with pre- and post-treatment overnight video-EEG. After EEG samples were preprocessed in an automated fashion to remove artifacts, we calculated amplitude, power spectrum, functional connectivity, entropy, and long-range temporal correlations (LRTCs). To evaluate the extent to which each feature is independently associated with response and relapse, we conducted logistic and proportional hazards regression, respectively. RESULTS: After statistical adjustment for the duration of epileptic spasms prior to treatment, we observed an association between response and stronger baseline and post-treatment LRTCs (P = 0.042 and P = 0.004, respectively), and higher post-treatment entropy (P = 0.003). On an exploratory basis, freedom from relapse was associated with stronger post-treatment LRTCs (P = 0.006) and higher post-treatment entropy (P = 0.044). CONCLUSION: This study suggests that multiple EEG features-especially LRTCs and entropy-may predict response and relapse. SIGNIFICANCE: This study represents a step toward a more precise approach to measure and predict response to treatment for epileptic spasms.

PyHFO: lightweight deep learning-powered end-to-end high-frequency oscillations analysis application.

Objective. This study aims to develop and validate an end-to-end software platform, PyHFO, that streamlines the application of deep learning (DL) methodologies in detecting neurophysiological biomarkers for epileptogenic zones from EEG recordings.Approach. We introduced PyHFO, which enables time-efficient high-frequency oscillation (HFO) detection algorithms like short-term energy and Montreal Neurological Institute and Hospital detectors. It incorporates DL models for artifact and HFO with spike classification, designed to operate efficiently on standard computer hardware.Main results. The validation of PyHFO was conducted on three separate datasets: the first comprised solely of grid/strip electrodes, the second a combination of grid/strip and depth electrodes, and the third derived from rodent studies, which sampled the neocortex and hippocampus using depth electrodes. PyHFO demonstrated an ability to handle datasets efficiently, with optimization techniques enabling it to achieve speeds up to 50 times faster than traditional HFO detection applications. Users have the flexibility to employ our pre-trained DL model or use their EEG data for custom model training.Significance. PyHFO successfully bridges the computational challenge faced in applying DL techniques to EEG data analysis in epilepsy studies, presenting a feasible solution for both clinical and research settings. By offering a user-friendly and computationally efficient platform, PyHFO paves the way for broader adoption of advanced EEG data analysis tools in clinical practice and fosters potential for large-scale research collaborations.

A case of recurrent acute encephalopathy with febrile convulsive status epilepticus with carnitine palmitoyltransferase II variation.

Acute encephalopathy with febrile convulsive status epilepticus (AEFCSE) is the most common type of acute encephalopathy in childhood in Japan, which develops with prolonged febrile convulsion, followed by mild unconsciousness. It is generally sporadic and nonrecurrent. In this report, a 1-year-old girl showed signs of AEFCSE triggered by respiratory syncytial virus infection. Two years later, she presented with AEFCSE triggered by influenza virus infection, resulting in severe neurologic sequelae. The patient had a thermolabile genotype of carnitine palmitoyltransferase II (CPT II) variations consisting of three single nucleotide polymorphisms in exons 4 [1055T > G/F352C and 1102G > A/V368I] and 5 [1939A > G/M647V]. The polymorphism has been identified as a genetic predisposition for acute encephalopathy. This report presents the first case of recurrent encephalopathy with CPT II variations that may partially associate with pathogenesis of recurrent AEFCSE.

Altered serum levels of platelet-derived growth factor receptor ß and cluster of differentiation 13 suggest a role for pericytes in West syndrome.

BACKGROUND: Pericytes play a role in the maintenance of the blood-brain barrier and neuroinflammation, attracting attention as to whether they are also involved in the pathogenesis of epilepsy.This study aimed to explore the relationship between West syndrome and pericytes. METHODS: Eighteen Japanese pediatric West syndrome patients and nine controls aged 2 years or younger were retrospectively enrolled in this study. We assessed theserumlevels of pericyte markers, serum PDGFRß (platelet-derived growth factor receptorß),CD13 (aminopeptidase N), and 27 cytokines in 17 pediatric patients with West syndrome and the control group. RESULTS: Patients with West syndrome exhibited significantly increased CD13 and decreased PDGFRß levels, compared with controls but not serum cytokine levels. These values did not differ significantly between symptomatic and idiopathic West syndrome. CONCLUSION: Pericytes might be implicated in the pathogenesis of West syndrome.

Optimizing detection and deep learning-based classification of pathological high-frequency oscillations in epilepsy.

OBJECTIVE: This study aimed to explore sensitive detection methods for pathological high-frequency oscillations (HFOs) to improve seizure outcomes in epilepsy surgery. METHODS: We analyzed interictal HFOs (80-500 Hz) in 15 children with medication-resistant focal epilepsy who underwent chronic intracranial electroencephalogram via subdural grids. The HFOs were assessed using the short-term energy (STE) and Montreal Neurological Institute (MNI) detectors and examined for spike association and time-frequency plot characteristics. A deep learning (DL)-based classification was applied to purify pathological HFOs. Postoperative seizure outcomes were correlated with HFO-resection ratios to determine the optimal HFO detection method. RESULTS: The MNI detector identified a higher percentage of pathological HFOs than the STE detector, but some pathological HFOs were detected only by the STE detector. HFOs detected by both detectors had the highest spike association rate. The Union detector, which detects HFOs identified by either the MNI or STE detector, outperformed other detectors in predicting postoperative seizure outcomes using HFO-resection ratios before and after DL-based purification. CONCLUSIONS: HFOs detected by standard automated detectors displayed different signal and morphological characteristics. DL-based classification effectively purified pathological HFOs. SIGNIFICANCE: Enhancing the detection and classification methods of HFOs will improve their utility in predicting postoperative seizure outcomes.

Optimizing Detection and Deep Learning-based Classification of Pathological High-Frequency Oscillations in Epilepsy.

Objective: This study aimed to explore sensitive detection methods and deep learning (DL)-based classification for pathological high-frequency oscillations (HFOs). Methods: We analyzed interictal HFOs (80-500 Hz) in 15 children with medication-resistant focal epilepsy who underwent resection after chronic intracranial electroencephalogram via subdural grids. The HFOs were assessed using the short-term energy (STE) and Montreal Neurological Institute (MNI) detectors and examined for pathological features based on spike association and time-frequency plot characteristics. A DL-based classification was applied to purify pathological HFOs. Postoperative seizure outcomes were correlated with HFO-resection ratios to determine the optimal HFO detection method. Results: The MNI detector identified a higher percentage of pathological HFOs than the STE detector, but some pathological HFOs were detected only by the STE detector. HFOs detected by both detectors exhibited the most pathological features. The Union detector, which detects HFOs identified by either the MNI or STE detector, outperformed other detectors in predicting postoperative seizure outcomes using HFO-resection ratios before and after DL-based purification. Conclusions: HFOs detected by standard automated detectors displayed different signal and morphological characteristics. DL-based classification effectively purified pathological HFOs. Significance: Enhancing the detection and classification methods of HFOs will improve their utility in predicting postoperative seizure outcomes. HIGHLIGHTS: HFOs detected by the MNI detector showed different traits and higher pathological bias than those detected by the STE detectorHFOs detected by both MNI and STE detectors (the Intersection HFOs) were deemed the most pathologicalA deep learning-based classification was able to distill pathological HFOs, regard-less of the initial HFO detection methods.

Uncovering Spatiotemporal Dynamics of the Corticothalamic Network during Seizures.

Objective: Although the clinical efficacy of deep brain stimulation targeting the anterior nucleus (AN) and centromedian nucleus (CM) of the thalamus has been actively investigated for the treatment of medication-resistant epilepsy, few studies have investigated dynamic ictal changes in corticothalamic connectivity in human EEG recording. This study aims to establish the complex spatiotemporal dynamics of the ictal corticothalamic network associated with various seizure foci. Methods: We analyzed ten patients (aged 2.7-28.1) with medication-resistant focal epilepsy who underwent stereotactic EEG evaluation with thalamic coverage. We examined both undirected and directed connectivity, incorporating coherence and spectral Granger causality analysis (GCA) between the diverse seizure foci and thalamic nuclei (AN and CM). Results: In our analysis of 36 seizures, coherence between seizure onset and thalamic nuclei increased across all frequencies, especially in slower bands (delta, theta, alpha). GCA showed increased information flow from seizure onset to the thalamus across all frequency bands, but outflows from the thalamus were mainly in slower frequencies, particularly delta. In the subgroup analysis based on various seizure foci, the delta coherence showed a more pronounced increase at CM than at AN during frontal lobe seizures. Conversely, in limbic seizures, the delta coherence increase was greater at AN compared to CM. Interpretation: It appears that the delta frequency plays a pivotal role in modulating the corticothalamic network during seizures. Our results underscore the significance of comprehending the spatiotemporal dynamics of the corticothalamic network during seizures, and this knowledge could guide personalized neuromodulation treatment strategies.

Production of chemokines in respiratory syncytial virus infection with central nervous system manifestations.

Respiratory syncytial virus (RSV) infection in children can be associated with acute encephalopathy. However, the roles of cytokines in the cerebrospinal fluid (CSF) of such patients remain unevaluated. In this study, a profile of 17 cytokines was determined for eight RSV-infected children with neurological complications. In one patient with high levels of 13 cytokines, a cytokine storm was considered to have occurred. Interleukin (IL)-6, IL-8, monocyte chemoattractant protein (MCP)-1, and macrophage inflammatory protein (MIP)-1ß levels were also high in other patients. These data suggest that chemokines in CSF play roles in neurological complications in RSV-infected children.