Focal Discharges Research Articles

Clinical features of KCNB1 gene variation related developmental and epileptic encephalopathy

Objective: To summarize the clinical features of epilepsy and (or) developmental delay associated with KCNB1 gene variants in children. Methods: A case series study was conducted on 24 children with KCNB1 gene variants associated with epilepsy and (or) developmental delay who were treated at the Children's Medical Center of Peking University First Hospital and the Department of Neurology of Shenzhen Children's Hospital from July 2015 to June 2024. The manifestations of seizures, electroencephalogram (EEG) and genetic test results of those children were analyzed. Results: All the KCNB1 gene variants were de novo, involving 20 different variation, including 15 missense variations, 3 frameshift variations and 2 nonsense variations. There were 7 novel variations. Among the 24 developmental and epileptic encephalopathy children, there were 14 boys and 10 girls. The last follow-up age ranged from 9 months to 13 years and 9 months. Seizures were present in 21 children (88%), with onset ranging from 1 month to 7 years, and 76% (16/21) began before 2 years of age. The seizure types included focal seizures in 15 children (71%), epileptic spasms, myoclonic seizures, and generalized tonic-clonic seizures in 6 children respectively, atypical absence seizures in 4 children, and myoclonic atonic seizures in 1 child. Seventeen children (81%) had a cluster of seizures and 5 had a history of focal status epilepticus with impaired consciousness. All 24 children had varying degrees of developmental delay, with 3 presenting solely developmental delay. EEG abnormalities were present in all the 21 children with seizures, including focal or multifocal discharges in 20 children, generalized discharges in 10 children, hypsarrhythmia in 2 children, and electrical status epilepticus during sleep in 3 children. Magnetic resonance imaging abnormalities were found in 5 of the 24 children. Among the 21 children with seizures, 57% (12/21) achieved seizure control. Conclusions: KCNB1 gene variants are predominantly de novo missense variation. Most affected children present with epilepsy, though some may exhibit only developmental delay. Epilepsy often begins before 2 years of age, with focal seizures being the most common type. About 80% of patients experience clustered seizures. Although most patients achieve seizure control, they still exhibit varying degrees of developmental delay, consistent with developmental epileptic encephalopathy.

Utility of Various Activation Procedures in Provoking Ictal and Interictal Patterns, during Routine Electroencephalogram (rEEG) Recording.

Activation procedures (APs) are adopted during routine electroencephalography (rEEG) to provoke interictal epileptiform abnormalities (EAs). This study aimed to observe interictal and ictal (EAs) of different EEG patterns, provoked by various APs. This cross-sectional study was performed in the neurology department of King Fahd hospital of university, Saudi Arabia. The EEGs and medical records of patients who presented for EEG recordings were screened initially, then 146 EEGs provoked EAs due to utilization of APs, were included for analysis. Among all EEGs with provoked EAs, Non-rapid eye movement sleep (NREM) provoked EAs in 93 (63.7%) patients with following patterns, focal spike wave discharges (FSWDs) 45 (P= 0.01), focal spike wave discharges with bilateral synchrony (FSWDBS) 27 (P=0.03) and generalized spike wave discharges (GSWDs) 46 (P=0.01). Intermittent photic stimulation (IPS) most significantly provoked FSWDs in 07 patient (P =0.01) and GSWDs in 30 patients (P=<0.001) 7 patients (P = 0.01) and GSWDs in 30 patients (P < 0.001). Hyperventilation (HV) was associated with a higher occurrence of GSWDs in 37 patients (P =0.01). Female sex 7 (P = 0.02), provoked GSWDs 3 (P = 0.03), NREM sleep 8 (P = 0.04), prolonged EEG record 3 (P = 0.02), clinical events during recording 5 (P ≤ 0.01), diagnosis of genetic 05 (P = 0.03), and immune-mediated epilepsies 2 (P = 0.001) were associated with the provocation of ictal EAs; however, in multiple logistic regression analysis, no statistically significant association of these variables (P ≥ 0.05 each) was noted. The provocation of EAs in rEEG with different APs varies according to circumstances, including seizure types, epilepsy etiology, and the type of AP applied. These clinical and procedural parameters affect the diagnostic yield of rEEG and need careful consideration during rEEG recordings. APs adopted during rEEG recording can induce FSWDs, FSWDBS, and GSWDs in the form of either interictal or ictal EAs in various etiologies of epilepsy. Ictal EAs may appear in the form of GSWDs, during NREM sleep, in prolonged EEG records; however, their independent association needs to be evaluated in larger sample studies. Further, prospective cohort studies with adequate sample sizes are warranted.

Combined generalized and focal epilepsy with reflex features in Adaptor protein complex 4-associated hereditary spastic paraplegias: A cohort observational study

BackgroundPatients with genetic deficiency of the adaptor protein complex 4 (AP-4) exhibit earlyonset developmental delay, spastic diplegia, intellectual disability, speech impairment. The phenotype overlaps with other hereditary spastic paraplegias and cerebral palsies. Febrile seizures are common at onset. Epilepsy has been described in more than half of cases, arising in early infancy often with status epilepticus, but no typical seizure semiology or electroencephalographic features have been identified thus far. PurposeWe aimed to specifically investigate the epileptological characteristics of the syndrome to unveil possible biomarkers of seizure development and prognosis in AP-4 deficiency. MethodsObservational cohort study on patients with bi-allelic pathogenic variants in AP-4 subunits and epilepsy. We focused on the seizure semiology, electroencephalographic characteristics and response to antiseizure medications. ResultsPatients harboured pathogenic variants in AP4S1 (n = 5) or AP4M1 (n = 1). The phenotype included spastic paraparesis, intellectual disability, speech/language impairment, microcephaly, and MRI evidence of hypoplasia of the corpus callosum. In 66 % of the patients, febrile seizures preceded the onset of epilepsy, which spanned from infancy to adolescence (range=14 months-13 years). Absences (66 %) and focal motor seizures (50 %) were common. No patient met the criteria for drug-resistance. Peculiar electroencephalographic features arose after the epilepsy onset and persisted at long-term follow-up: bilateral and asynchronous focal discharges combined with independent diffuse spike-wave-discharges (100 %) and reflex abnormalities (66 %). ConclusionIn AP-4 complex disease, epilepsy could arise beyond early infancy, until adolescence, with variable combination of generalized and focal seizures. The prognosis was favourable. We observed a common electroencephalographic signature - combined focal/generalized and reflex abnormalities - which may constitute a biomarker of AP-4 deficiency with epilepsy, applicable to inform genetic testing and disentangle the differential diagnosis.

Genotype and phenotype of WWOX gene related developmental and epileptic encephalopathy

Objective: To summarize the genotype and clinical phenotype of children with WWOX gene related developmental and epileptic encephalopathy (DEE). Methods: Case series studies. The clinical data of 12 children with WWOX gene related DEE who were admitted to the Neurological Department of Children's Medical Center, Peking University First Hospital from June 2019 to December 2023 were analyzed. The children's characteristics of gene variation, clinical phenotype, auxiliary examination results, treatment and prognosis were analyzed. Results: Among 12 children with WWOX gene related DEE, there were 7 boys and 5 girls, the age of seizure onset ranged from 10 days to 6 months (median 1.8 months). Multiple seizure types were observed, including focal seizures in 10 cases, epileptic spasms in 9 cases, tonic seizures in 4 cases, myoclonic seizures in 1 case. Among 12 cases, 9 cases had multiple seizure types. All 12 cases showed microcephaly and global developmental delay. Video electroencephalography showed slowed background activity in 6 cases, hyperarrhythmia in 6 cases, multifocal discharges in 6 cases, and focal discharges in 1 case. Epileptic spasms were detected in 8 cases, tonic seizures in 4 cases and myoclonic seizures in 1 case. Brain magnetic resonance imaging showed bilateral frontotemporal subarachnoid space widening in 5 cases, deep sulci in 3 cases, bilateral ventricular enlargement in 2 cases, callosal hypoplasia in 5 cases, and delayed white matter myelination in 3 cases. The phenotypes of 12 cases were consistent with the diagnosis of DEE, and 8 of them were diagnosed with infantile epileptic spasm syndrome. All the WWOX gene variants in 12 cases were complex heterozygous variants, including 20 variants, 11 variants and 1 large intragenic WWOX gene deletion (p.Ala149Thr, p.Arg156Ser, p.R167Tfs*8, p.Leu186Val, c.605+5G>A, p.Trp218*, p.His263Arg, p.Leu275fs*19*1, p.N285Kfs*10, p.Ser304Tyr, p.Met326Arg, loss1 exon2-8) had not been reported previously. The age of last follow-up ranged from 11 months to 5 years and 3 months. During the follow-up, 1 case died at the age of 1 year and 10 months, 2 cases were seizure-free, and 9 cases still had seizures after multiple anti-seizure medications. Conclusions: The seizure onset age of children with WWOX gene related DEE is usually less than 6 months, and some of them in neonate. The common seizure types include focal seizures and epileptic spasms. Children usually have microcephaly and global developmental delay. WWOX gene related DEE usually has drug refractory epilepsy.

Are the seizures under control or unnoticed? Electroclinical evaluation of epilepsy with eyelid myoclonia

PurposeIn this study, patients with epilepsy with eyelid myoclonia (E-EM) were evaluated according to their EEG findings, seizure outcomes, and their consistency with the final ictal EEG findings. We also investigated the possible prognostic factors. MethodsPatients with E-EM and at least two years of follow-up in our clinic were included in the study. We analyzed the presence of eyelid myoclonia, absence and myoclonic seizures, and generalized tonic-clonic seizures for the prior two years and then verified with the latest ictal EEG features. Video-EEGs were analyzed according to the background activity, the existence of generalized spike-wave discharge or polyspike-wave complexes, focal spike-wave discharge, photoparoxysmal responses, and fast activity. Results21 patients were involved in this study. In six patients, the seizures were undetected on the first EEGs, whereas they were detected on subsequent ones. The seizures were captured on the first EEGs of six patients; however, they disappeared on subsequent ones. Only one patient had seizures detected on every EEG. The consistency of the seizures was variable in eight patients. At the final follow-up, seizures were reported as being under control for more than two years in 12 patients, according to patients and their parents’ reports. However, ictal EEG findings were detected in six of these patients. No electroclinical feature was associated with seizure freedom. ConclusionThis study provides further evidence that seizure freedom in E-EM patients is overestimated. The patients and their parents may not be aware of the seizures. Therefore, video-EEG monitorization is essential during follow-up.

Clinical features and surgical outcomes in temporal lobe epilepsy with amygdala enlargement - a single tertiary center study

Objective: To analyze and summarize clinical features and surgical outcomes in temporal lobe epilepsy with amygdala enlargement (TLE-AE) in a single tertiary center. Methods: Patients with TLE-AE admitted to the Neurological Disease Center of Peking University International Hospital from January 2016 to September 2022 were continuously collected. The clinical data of TLE-AE patients were retrospectively analyzed. Results: A total of 19 patients with TLE-AE were included. The average age at onset was (29.0 ± 14.5) years and all patients had focal impairment awareness seizure (FIAS). Ten (52.6%) patients were in line with drug-resistant epilepsy and 8 cases received surgical treatment. Focal temporal interictal epileptiform discharges on scalp electroencephalography were exclusively present ipsilateral to AE in 15 (78.9%) patients. Stereo-electroencephalography analysis found the ictal onset zone involved not only the enlarged amygdala but also the hippocampus in 2 patients. Two patients who responded well to antiseizure medication exhibited AE remission on follow-up MRI. Histopathology of the amygdala showed focal cortical dysplasia (FCD) in 7 patients and ganglioglioma in 1 patient. The 8 surgical patients were followed up for 13-79 months after operation. Six (75.0%) patients achieved Engel class Ia or I outcome, whereas 2 cases did not fully respond to the surgery (Engel class II). Conclusions: Patients with TLE-AE had a later age of seizure onset and FIAS was common. The epileptogenic zone in TLE-AE patients may be located in the enlarged amygdala and ipsilateral hippocampus. AE might be a secondary seizure-induced change in a subset of patients with favorable responses to drugs. As for drug-resistant patients, FCD may be the most common pathological change and surgical treatment could be taken into consideration.

Enhancing OpenEP: atrial conduction velocity and conduction velocity heterogeneity quantification through EP Workbench

Abstract Background Alterations in atrial conduction velocity have been implicated in the pathogenesis of atrial arrhythmias, with conduction velocity thought to be slower and more heterogeneous in areas promoting atrial fibrillation. However, clinical studies of conduction velocity are challenging since there are no available platforms that provide researchers and clinicians with the ability to quantify conduction velocity and analyse conduction heterogeneity from electroanatomic mapping data. Purpose In this paper we sought to address these limitations by enhancing the OpenEP Python library by (1) automating calculations using previously-published conduction velocity estimation algorithms; (2) providing an interactive graphical representing of conduction velocity and conduction heterogeneity and (3) implementing a histogram analysis tool to quantify conduction velocity and enable the identification of slow conduction regions. Method Two well-known and previously published methods for calculating cardiac conduction velocity, Triangulation and polynomial surface fitting, were implemented. Conduction velocity estimation was improved further by excluding regions with wave collisions and focal discharges. These regions were identified using the divergence of conduction velocity vector fields, with positive divergence representing focal sources and negative divergence representing areas of collision. Finally, calculated conduction velocities using electrogram data were interpolated over the surface mesh via Radial Basis Function (RBF) interpolation method. All algorithms were implemented in the OpenEP Python library (openep-py), with visualisation tools provided in the complementary graphical interface, EP Workbench. Results An extensible "Analysis" feature was created in openep-py, to provide conduction velocity and divergence calculations which are fully customisable through the graphical interface based on user preferences. The EP Workbench desktop application displays resulting cardiac surface maps to depict calculated conduction velocity and divergence fields, together with conventional activation and voltage maps (Figure 1). The histogram analysis tool can be used to identify regions of slow conduction velocity from electroanatomic mapping data. Using a threshold of &amp;lt;0.3m/s, two slow conducting channels are visualised on the posterior wall of a test case (Figure 2). The tool is not specific to conduction velocity and may also be used to quantify other data types in EP Workbench. Finally, computed conduction velocity and divergence values and surface maps are stored in the standard OpenEP data structure, allowing further analysis following data export. Conclusion We have extended OpenEP to provide a comprehensive set of tools for conduction velocity calculation and analysis which will facilitate investigation of the structural and functional basis of conduction velocity alterations in disease states.

BDNF, proBDNF and proBDNF/BDNF ratio with electroencephalographic abnormalities in children with attention deficit hyperactivity disorder: Possible relations to cognition and severity.

Attention deficit hyperactivity disorder (ADHD) with and without subclinical epileptogenic discharges (SED) have been suggested to negatively affect cognitive abilities of children with ADHD. The role of brain-derived neurotrophic factor (BDNF) and its precursor proBDNF in ADHD is in need of being investigated. The aims were to evaluate the levels of serum BDNF, proBDNF and the proBDNF/BDNF ratio in addition to the potential impacts of SED on the children's cognitive abilities and the severity of ADHD. The included participants with ADHD were 30 children with normal electroencephalogram (EEG) (G1) and 30 children with SED (G2), together with 30 healthy children (G3). The cognitive abilities and severity of the disorder were evaluated. The biochemical measures were determined by ELISA. The presence of coexisting SED and nocturnal enuresis has led to a deleterious effect on cognitive processes but not on the severity. The focal epileptogenic discharge was the most common among children in G2. The levels of BDNF in Groups 1 and 2 were less than those in G3. The higher proBDNF/BDNF ratio could be related to the low BDNF levels rather than high proBDNF levels. The findings of this study highlight the importance of investigating the presence of SED and nocturnal enuresis in children with ADHD. Targeting strengthening of cognitive abilities in children with coexisting ADHD and SED is advised. The role of proBDNF in the pathophysiology of ADHD needs further investigation.

Focality in childhood absence epilepsy

ABSTRACT Background and purpose Childhood absence epilepsy (CAE) has a typical electroencephalography (EEG) pattern of generalized 3 Hz spike and wave discharges (SWD). Focal interictal discharges were also documented in a small number of documents. The aim was to investigate the amplitudes of interictal 3 Hz SWD within the 1st second in drug-naïve CAE patients. In this way, areas with maximal electronegativity at the beginning of clinically generalized discharges will be documented. Methods The EEG records of children with drug-naïve CAE were evaluated retrospectively by two child neurologists first for 3 Hz SWD. Then, a machine-learning model evaluated the amplitudes of 3 Hz in the 1st second of SWD. Maximum electronegativity areas were documented and classified as focal, bilateral, and generalized. Results One hundred and twelve 3 Hz SWD were evaluated in 11 patients. Among discharges within the 1st second, maximum electronegativity areas were documented as focal for 44 (39.2%), bilateral for 8 (7.1%), generalized for 60 (53.5%). Among focal electronegativity areas, mostly right central, left occipital and midline parietal areas were documented in 12 (10.7%), 7 (6.2%), and 6 (5.3%), respectively. Eight (7.1%) of the maximum electronegativity areas were detected bilaterally, of which 7 (6.2%) originated from the frontopolar areas. Conclusions Focal maximal electronegativity areas were frequently observed in drug-naïve CAE patients, comprising approximately half of non-generalized discharges. Focal discharges might be misleading in diagnosis. Focal areas within the brain may be responsible for and contribute to absence seizures that appear bilaterally symmetrical and generalized clinically. Although its clinical implication is unknown, this warrants further study.

Idiopathic generalized epilepsies in the epilepsy monitoring unit: Systematic quantification of focal EEG and semiological signs

ObjectiveFocal seizure symptoms (FSS) and focal interictal epileptiform discharges (IEDs) are common in patients with idiopathic generalized epilepsies (IGEs), but dedicated studies systematically quantifying them both are lacking. We used automatic IED detection and localization algorithms and correlated these EEG findings with clinical FSS for the first time in IGE patients. Methods32 patients with IGEs undergoing long-term video EEG monitoring were systematically analyzed regarding focal vs. generalized IEDs using automatic IED detection and localization algorithms. Quantitative EEG findings were correlated with FSS. ResultsWe observed FSS in 75% of patients, without significant differences between IGE subgroups. Mostly varying/shifting lateralizations of FSS across successive recorded seizures were seen. We detected a total of 81,949 IEDs, whereof 19,513 IEDs were focal (23.8%). Focal IEDs occurred in all patients (median 13% focal IEDs per patient, range 1.1 – 51.1%). Focal IED lateralization and localization predominance had no significant effect on FSS. ConclusionsAll included patients with IGE showed focal IEDs and three-quarter had focal seizure symptoms irrespective of the specific IGE subgroup. Focal IED localization had no significant effect on lateralization and localization of FSS. SignificanceOur findings may facilitate diagnostic and treatment decisions in patients with suspected IGE and focal signs.

Video-electroencephalographic findings and clinical characteristics of bathing seizures in children.

To explore the electroencephalogram (EEG) and clinical characteristics of childhood bathing epilepsy. We conducted a prospective summary of the clinical data from 10 children with bathing epilepsy who were admitted to Hunan Children's Hospital from April 2019 to November 2023 and analyzed their EEGs and clinical characteristics. Our 10 patients included eight males and two females, with seizure-onset ages ranging from 4 months and 20 days to 14 months. Nine cases showed normal intellectual development, and one case manifested delayed development. The Video-EEG (VEEG) findings showed that nine cases exhibited normal background with no interictal epileptic discharge. The seizures were characterized by lip cyanosis, tachycardia or bradycardia, weakness, paleness, and loss of consciousness. Ictal EEG revealed rhythmic fast waves, spike waves, spike-slow waves, or slow and sharp-wave activity over the temporal region (eight cases) or the occipital and temporal regions (one case), finally evolving into a delta rhythm that lasted for 57-201 s. These children exhibited no seizures after discontinuing bathing and were not administered antiseizure medication. The interictal EEG of one case reflected mild slow background and focal interictal epileptic discharge; and her semiology was eyes gazing to right, with clonic movements of the right face and lips, lip cyanosis, bradycardia, and impaired consciousness. Ictal EEG showed spike-wave and spike-slow-wave rhythms over the left central, parietal, and temporal regions; these then spread to the left hemisphere, lasting for approximately 104 s. This patient did not exhibit bathing seizures after stopping her bathing but later experienced frequent spontaneous and drug-resistant seizures. The interictal EEG background slowed down, while focal epileptic discharge increased. Her intellectual development was significantly delayed, and a novel pathogenic mutation in the SMC1A gene, c.298+2T>C, was detected. She was diagnosed with developmental and epileptic encephalopathy. A majority of children with bathing epilepsy in our study showed focal autonomic seizures accompanied by impaired consciousness. Stopping bathing could control the seizures and showed a good prognosis. A few infants manifested a poor prognosis, and we posit that bathing seizure rarely constitute the early manifestations of developmental and epileptic encephalopathy. VEEG findings and clinical features can also indicate the prognosis.

Clinical Implications of Various Electroencephalographic Patterns in Post-Stroke Seizures. The Utility of Routine Electroencephalogram.

Objective: Post-stroke seizures (PSS) are one of the major stroke-related complications. Early therapeutic interventions are critical therefore using electroencephalography (EEG) as a predictive tool for future recurrence may be helpful. We aimed to assess frequencies of different EEG patterns in patients with PSS and their association with seizure recurrence and functional outcomes. Methods: All patients admitted with PSS were included and underwent interictal EEG recording during their admission and monitored for seizure recurrence for 24 months. Results: PSS was reported in 106 patients. Generalized slow wave activity (GSWA) was the most frequent EEG pattern observed (n = 62, 58.5%), followed by Focal sharp wave discharges (FSWDs) (n = 57, 55.8%), focal slow wave activity (FSWA) (n = 56, 52.8%), periodic discharges (PDs) (n = 13, 12.3%), and ictal epileptiform abnormalities (n = 6, 5.7%). FSWA and ictal EAs were positively associated with seizure recurrence (p < .001 and p = .015 respectively) and it remained significant even after adjusting for age, sex, stroke severity, stroke subtype, or use of anti-seizure medications (ASMs). Other positive associations were status epilepticus (SE) (p = .015), and use of older ASM (p < .001). FSWA and GSWA in EEG were positively associated with severe functional disability (p = .055, p = .015 respectively). Other associations were; Diabetes Mellitus (p = .034), Chronic Kidney Disease (p = .002), use of older ASMs (p = .037), presence of late PSS (p = .021), and those with Ischemic stroke (p = .010). Conclusions: Recognition and documentation of PSS-related EEG characteristics are important, as certain EEG patterns may help to identify the patients who are at risk of developing recurrence or worse functional outcomes.

Focal electroclinical features in generalized tonic-clonic seizures: Decision flowchart for a diagnostic challenge.

Bilateral tonic-clonic seizures with focal semiology or focal interictal electroencephalography (EEG) can occur in both focal and generalized epilepsy types, leading to diagnostic errors and inappropriate therapy. We investigated the prevalence and prognostic values of focal features in patients with idiopathic generalized epilepsy (IGE), and we propose a decision flowchart to distinguish between focal and generalized epilepsy in patients with bilateral tonic-clonic seizures and focal EEG or semiology. We retrospectively analyzed video-EEG recordings of 101 bilateral tonic-clonic seizures from 60 patients (18 with IGE, 42 with focal epilepsy). Diagnosis and therapeutic response were extracted after ≥1-year follow-up. The decision flowchart was based on previous observations and assessed concordance between interictal and ictal EEG. Focal semiology in IGE was observed in 75% of seizures and 77.8% of patients, most often corresponding to forced head version (66.7%). In patients with multiple seizures, direction of head version was consistent across seizures. Focal interictal epileptiform discharges (IEDs) were observed in 61.1% of patients with IGE, whereas focal ictal EEG onset only occurred in 13% of seizures and 16.7% of patients. However, later during the seizures, a reproducible pattern of 7-Hz lateralized ictal rhythm was observed in 56% of seizures, associated with contralateral head version. We did not find correlation between presence of focal features and therapeutic response in IGE patients. Our decision flowchart distinguished between focal and generalized epilepsy in patients with bilateral tonic-clonic seizures and focal features with an accuracy of 96.6%. Focal semiology associated with bilateral tonic-clonic seizures and focal IEDs are common features in patients with IGE, but focal ictal EEG onset is rare. None of these focal findings appears to influence therapeutic response. By assessing the concordance between interictal and ictal EEG findings, one can accurately distinguish between focal and generalized epilepsies.

Association of Epileptiform Discharge and Autism Spectrum Disorder Severity in Children Attending the Outpatient Clinics, Child Welfare Teaching Hospital, Baghdad

Background: Subjects with Autism Spectrum Disorder (ASD) have a higher prevalence of seizures than the general population, according to a significant body of research. Also, seizure-free patients with ASD have been found to have a higher prevalence of epileptiform discharge abnormalities compared to healthy controls across investigations. Changes in the electroencephalogram (EEG) can manifest as sharp waves or spikes, sharp and slow waves, generally distributed or general area, or focused, and can manifest in various brain regions. There is a necessity to search for a distinctive EEG characteristic in ASD patients. Objectives: This study used electroencephalography to investigate the relationship between interictal epileptiform discharges and the severity of ASD in children. Patient and methods: The study involved a total of 65 children. The first group consisted of 30 children (seven females and 23 males, 2-12 years of age) recruited from the autism center and the pediatric neurology consultancy clinic in the Child Welfare Teaching Hospital / Medical City. The second group consisted of 35 age- and gender-matched normally-developed children (10 females 25 males, 2-12 years of age) recruited from the Pediatrics Consultation Clinics in the Child Welfare Teaching Hospital. The ASD children met the DSM-5 criteria for autism and the Childhood Autism Rating Scale was utilized to determine the severity of autism. The electroencephalography signals were recorded to detect epileptiform discharge. The data was collected during the period from 5th October 2022 to 1st April 2023. Result: A statistically significant association was found between the epileptiform discharges and the study group (ASD Vs normally developed children). The EEG records were normal in 20 (66.7%), abnormal in the form of focal epileptiform discharge in 5 (16.7%), and in the form of generalized epileptiform discharge in 5 (16.7%) of ASD children. The EEG findings and the CARS-measured autism severity showed a statistically significant association (P=0.05), as the EEG abnormalities increased with the severity of autism. Conclusion: The degree of autism was found to be associated with the abnormalities of the electroencephalogram and the degree of autism. Received: May,, 2023 Accepted: Sept, 2023 Published: Jan. 2024

Clinical phenotype and genetic characteristics of SZT2 related diseases: A case report and literature review

PurposeSeizure threshold 2 protein homolog gene (SZT2, MIM: 615463) related diseases are extremely rare autosomal recessive disorders with a wide spectrum of clinical phenotypes ranging from mild intellectual impairment to severe developmental epileptic encephalopathy (DEE). Most SZT2 related diseases are accompanied by craniofacial malformation and corpus callosum malformation. This study attempts to analyze and summarize the clinical phenotype and genetic characteristics of SZT2 related diseases, providing a basis for early diagnosis, treatment, and prognosis. MethodWe analyzed the clinical characteristics of a Chinese child with pathogenic variants of SZT2. We also performed whole-exome sequencing (WES) on the patient. In addition, we conducted a literature review of previously reported patients with pathogenic mutations in the SZT2 gene. ResultThe proband was a boy aged 1 year and 9 months with severe global developmental delay, transient drug-controlled focal epilepsy, cluster epilepsy, autism spectrum disorder, craniofacial deformity, hypotonia, focal EEG discharge, corpus callosum malformation, and persistent cavum septum pellucidum. WES revealed that the patient carried the SZT2 gene c.7584dupA and c.6302A>C complex heterozygous variants; the former being Likely Pathogenic (LP) and the latter Uncertain Significance (VUS) according to ACMG classification guidelines. According to our literature review, 43 cases of SZT2 related diseases have been reported so far; these include 15 cases with homozygous variations and 28 cases with complex heterozygous variations. A total of 57 types of variation were found, including 47 genetic variants, 2 de novo variants, and 8 unknown genetic modes. In addition, 2 high-frequency variants were found (c.5949_5951delTGT and c.6553C>T). The main clinical manifestations of the 40 patients were global developmental delay (GDD) of varying degrees (38/40, 95.00%), seizures (36/40, 90.00%), cranial deformity (27/40, 67.50%), facial deformity (22/40, 55.00%), hypotonia (22/40, 55.00%), abnormal interseizure EEG discharge (26/40, 65.00%), slow background activity (20/40, 50.00%), corpus callosum deformity (18/40, 45.00%). There was also one case of sudden unexpected death in epilepsy (SUDEP) and 3 cases of death from infection. In addition, three fetuses with the same variant had hydrocephalus and encephalocele. ConclusionThe compound heterozygous mutation of c.7584dupA and c.6302A>C in the SZT2 gene is the genetic etiology of this patient, expanding the mutation spectrum of SZT2 related diseases. Early genetic testing is the best choice for clear diagnosis, treatment, and prognosis.

Electroencephalographic abnormalities in children with type 1 diabetes mellitus: a prospective study.

The aim herein was to investigate epileptiform discharges on electroencephalogram (EEG), their correlation with glutamic acid decarboxylase 65 autoantibody (GAD-ab) in newly diagnosed pediatric type 1 diabetes mellitus (T1DM) patients and interpret their medium-term utility in predicting epilepsy. Children presenting with T1DM between July 2018 and December 2019 were included in this prospective longitudinal study. Patients with a history of head injury, chronic illness, neurological disorder, seizure, autism, or encephalopathy were excluded. EEGs were obtained within the first 7 days of diagnosis and later reviewed by a pediatric neurologist. All of the children were clinically followed-up in pediatric endocrinology and neurology clinics for 2 years after their diagnosis. A total of 105 children (46 male, 43.8%) were included. The mean age at the time of diagnosis was 9.6 ± 4.1 years (range: 11 months-17.5 years). At the time of admission, 24 (22.9%), 29 (27.6%), and 52 (49.5%) patients had hyperglycemia, ketosis, and diabetic ketoacidosis, respectively. GAD-ab was positive in 55 children (52.4%). No background or sleep architecture abnormalities or focal slowing were present on the EEGs. Of the patients, 3 (2.9%) had focal epileptiform discharges. The mean GAD-ab levels of the remaining 102 patients were 7.48 ± 11.97 U/mL (range: 0.01-50.54) (p = 0.2). All 3 children with EEG abnormality had higher levels of GAD-ab (3.59 U/mL, 31.3 U/mL, and 7.09 U/mL, respectively). None of the patients developed epilepsy during the follow-up, although 1 patient experienced Guillain-Barré syndrome (GBS). The prevalence of epileptiform discharges in the patients was similar to those of previous studies, in which healthy children were also included. No relationship was found between the epileptiform discharges and GAD-ab, and none of the patients manifested seizures during the first 2 years of follow-up of T1DM. These data support the findings of previous studies reporting that T1DM patients with confirmed electroencephalographic abnormalities do not have an increased risk of epilepsy. On the other hand, GBS might be considered as another autoimmune disease that may be associated with T1DM in children.

Index of benign focal epileptiform discharges of childhood and specificity of cognitive functions development in children: А retrospective study

Index of benign focal epileptiform discharges of childhood and specificity of cognitive functions development in children: А retrospective study

Detection of interictal epileptiform discharge in focal seizures

Introduction: Many factors underlying basic epileptic conditions determine the characteristics of epileptic seizures and the therapeutic outcome. Visual obvious abnormalities in resting baseline EEG are cardinal but incompletely understood like feature of seizure onset zone in focal epilepsy and interictal epileptiform discharge. Present study is an attempt to diagnose that evidence of epileptic discharge in temporal lobe epilepsy (TLE), would persist during interictal period in absence of abnormalities in baseline EEG, which could increase the impact of automatic analysis of EEG waves for clinical relevance.&#x0D; Material and Methods: By using 10-20 system, functional connectivity was estimated in the 20 channels of delta, theta, alpha, beta and gamma frequency bands of EEG, from 16 diagnosed focal epileptic seizure patients and 16 age and sex matched controls. To observe the dynamics of the healthy brain, differ from the brain of dynamically focal epileptic patients during interictal period treated with anti-epileptic drugs in the context of resting state during eye close session of EEG. Such differences can be observed by using absolute spectral power from BESS ((Brain Electro Scan Software) of the Axxonet System and statistically measure by applied unpaired student t -test.&#x0D; Result: The high significance results in slow frequency EEG waves (delta and theta) in power spectral analysis were observed that demonstrates the potential epileptic discharge occurring during interictal period without visible pathological activity for helping in the diagnosis and lateralization of TLE.&#x0D; Conclusion: The detailed spectral analysis of EEG waves offers novel insight into focal epileptic patients when visually EEG findings were normal. This linear analysis helpful in extracting information from EEG signals in diagnosing specific neuronal correlates for TLE. Present findings concluded that epileptic discharges occur at different topographical regions of brain during interictal period and power spectral analysis plays a new insight in diagnosis of focal discharge.

The Agreement Between Long-Term Monitoring by Electroencephalography and Magnetic Resonance Imaging in Paediatric Seizure

Background: Demonstration of high agreement between structural abnormalities identified on magnetic resonance imaging (MRI) and physiologic abnormalities identified on electroencephalography (EEG) could benefit the assessment of epileptic focus in childhood seizures. Objectives: The present study aimed to assess the agreement between abnormal findings on brain MRI and long-term monitoring (LTM) by EEG as the standard protocol in children with abnormal focal epileptic discharges in LTM. Methods: This cross-sectional study was performed on 95 children who suffered from seizures with evidence of focal epileptic discharges in LTM who were referred to the Children's Medical Center in 2017. All patients were also concurrently evaluated by MRI. All MRIs were evaluated twice, before and after receiving the EEG results. Results: In this study, 59 out of 95 patients with abnormal LTM had concurrently abnormal MRI findings. The diagnostic agreement between the MRI and LTM in discovering abnormal findings was found to be high (86.4%) with a kappa correlation coefficient equal to 0.79. Conclusions: About two-thirds of patients with abnormal LTM findings had concurrent abnormal MRI features with high agreement between the two. Thus, MRI and EEG can be valuable in predicting epileptic focus in drug-resistant patients who need surgery.

Enhanced sensitivity of electrocorticography during awake craniotomy using a novel circular grid electrode.

Awake craniotomy with intraoperative functional brain mapping (FBM) bedside neurological testing is an important technique used to optimize resective brain surgeries near eloquent cortex. Awake craniotomy performed with electrocorticography (ECoG) and direct electrical stimulation (DES) for FBM can delineate eloquent cortex from lesions and epileptogenic regions. However, current electrode technology demonstrates spatial limitations. Our group has developed a novel circular grid with the goal of improving spatial recording of ECoG to enhance detection of ictal and interictal activity. This retrospective study was approved by the institutional review board at Mayo Clinic Florida. We analyzed patients undergoing awake craniotomy with ECoG and DES and compared ECoG data obtained using the 22 contact circular grid to standard 6 contact strip electrode. We included 144 cases of awake craniotomy with ECoG, 73 using circular grid and 71 with strip electrode. No significant differences were seen regarding preoperative clinical and demographic data, duration of ECoG recording (p = 0.676) and use of DES (p = 0.926). Circular grid was more sensitive in detecting periodic focal epileptiform discharges (PFEDs) (p = 0.004), PFEDs plus (p = 0.032), afterdischarges (ADs) per case (p = 0.022) at lower minimum (p = 0.012) and maximum (p < 0.0012) intensity stimulation, and seizures (p = 0.048). PFEDs (p < 0.001), PFEDs plus (p < 0.001), and HFOs (p < 0.001) but not ADs (p = 0.255) predicted electrographic seizures. We demonstrate higher sensitivity in detecting ictal and interictal activity on ECoG during awake craniotomy with a novel circular grid compared to strip electrode, likely due to better spatial sampling during ECoG. We also found association between PFEDs and intraoperative seizures.