Electroencephalographic Findings Research Articles

Efficacy of single dose of phenytoin/fosphenytoin in benign convulsions with mild gastroenteritis.

This study evaluated the efficacy of a single dose of phenytoin/fosphenytoin (PHT) to control repetitive seizures in children with benign convulsions with mild gastroenteritis (CwG). Children aged between 3 months and 5 years with CwG were retrospectively enrolled. Convulsions with mild gastroenteritis were defined as (a) seizures with acute gastroenteritis without fever or dehydration; (b) normal blood laboratory results; and (c) normal electroencephalography and brain imaging findings. Patients were divided into two groups according to whether or not intravenous PHT (10 mg/kg of phenytoin or phenytoin equivalents) was administered. Clinical manifestations and treatment efficacy were evaluated and compared. Ten of 41 children eligible for inclusion received PHT. Compared to children in the non-PHT group, those in the PHT group had a higher number of seizures (5.2 ± 2.3 vs. 1.6 ± 1.0, P < 0.001) and a lower serum sodium level (133.5 ± 3.2 mmol/L vs. 137.2 ± 2.6 mmol/L, P = 0.001). Initial serum sodium levels were negatively correlated with seizure frequency (r = -0.438, P = 0.004). In all patients, seizures were completely resolved with a single dose of PHT. There were no significant adverse effects from PHT. A single dose of PHT can effectively treat CwG with repetitive seizures. The serum sodium channel may play a role in seizure severity.

Epilepsy and drug-resistant epilepsy in neurocutaneous syndromes

Aim: Epilepsy frequently accompanies neurocutaneous syndromes. Due to the comorbid conditions that epileptic seizures may cause, their frequency, type, and duration also affect the prognosis of neurocutaneous diseases. The purpose of this study was to examine the frequency of epilepsy and drug-resistant epilepsy in neurocutaneous syndromes, and factors affecting the development of drug-resistant epilepsy.Methods: In our clinic, nine of the 24 patients who were under follow-up due to neurocutaneous syndromes were diagnosed with Tuberous Sclerosis Complex (TSC), six with Sturge-Weber syndrome, and nine with Neurofibromatosis type 1. We examined the age at diagnosis, findings at the time of the diagnosis, the presence of accompanying epilepsy, age at onset of seizures, seizure type and frequency, antiepileptic drugs used, responses to antiepileptic drugs, electroencephalography and brain magnetic resonance imaging findings, neurological-neuro-ophthalmological and physical examination results, and systemic findings.Results: Age at onset of seizures ranged between four months and four years. A pre-diagnosis history of seizure was present in all the patients with TSC, and the first seizure in 55% of the patients was epileptic spasm type. Hemiparesis and port wine stain were present at the time of diagnosis in Sturge-Weber syndrome, while accompanying seizures were observed later.Conclusion: The frequency of accompanying epilepsy and drug-resistant epilepsy is higher in the TSC.

Isolated Unilateral EEG Findings in Juvenile Myoclonic Epilepsy: A Case Report

Juvenile myoclonic epilepsy (JME) has well-defined clinical and electrophysiological features. On the other hand, large case series have shown that focal and asymmetrical discharges may accompany generalized epileptiform activities in JME. Although it is known that these non-generalized electrophysiological findings do not exclude the diagnosis of this syndrome, some findings may create confusion in the differential diagnosis. In this case report, a case of JME with electroencephalographic findings characterized by isolated unilateral epileptiform activities without typical generalized discharges was discussed. The current case clinically presented with involuntary jerk movements in the bilateral upper extremities. It has been determined that these movements are uni/bilateral myoclonic beats based on home video recordings. Metabolic, toxic and structural problems were excluded in the investigations for the etiology of myoclonus. In the electrophysiological examination performed for epileptic processes, epileptiform discharges localized to the isolated right hemisphere were observed. JME was considered primarily due to clinical findings in the patient, and effective seizure control was achieved in a 4-year follow-up under anti-seizure treatment. The peculiarity of the case is the presence of electrophysiology recordings of isolated unilateral epileptiform activity during the 4-year follow-up period. It should be emphasized that there is no case of JME diagnosed with isolated unilateral epileptiform activity in the absence of generalized spike-slow waves or multiple spike-slow waves in the literature.

Seizures, Epilepsy, and NORSE Secondary to Autoimmune Encephalitis: A Practical Guide for Clinicians.

The most recent International League Against Epilepsy (ILAE) classification has included "immune etiology" along with other well-known causes of epilepsy. This was possible thanks to the progress in detection of pathogenic neural antibodies (Abs) in a subset of patients, and resulted in an increased interest in identifying potentially treatable causes of otherwise refractory seizures. Most autoimmune encephalitides (AE) present with seizures, but only a minority of cases evolve to long-term epilepsy. The risk of epilepsy is higher for patients harboring Abs targeting intracellular antigens (T cell-mediated and mostly paraneoplastic, such as Hu, CV2/CRMP5, Ma2, GAD65 Abs), compared with patients with neuronal surface Abs (antibody-mediated and less frequently paraneoplastic, such as NMDAR, GABAbR, LGI1, CASPR2 Abs). To consider these aspects, conceptual definitions for two entities were provided: acute symptomatic seizures secondary to AE, and autoimmune-associated epilepsy, which reflect the different pathophysiology and prognoses. Through this manuscript, we provide an up-to-date review on the current state of knowledge concerning diagnosis and management of patients with Ab-mediated encephalitis and associated epilepsy. Special emphasis is placed on clinical aspects, such as brain magnetic resonance imaging (MRI) and cerebrospinal fluid (CSF) specificities, electroencephalographic (EEG) findings, cancer screening and suggestions for a rational therapeutic approach.

Temporal encephaloceles and coexisting epileptogenic lesions.

This study was performed to identify coexisting structural lesions in patients with epilepsy and known temporal encephaloceles (TEs). Forty-seven structural magnetic resonance imaging (MRI) scans of patients with epilepsy and radiologically diagnosed TEs were retrospectively reviewed visually and using an automated postprocessing software, the Morphometric Analysis Program v2018 (MAP18), to depict additional subtle, potentially epileptogenic lesions in the 3D T1-weighted MRI data. All imaging findings were evaluated in the context of clinical and electroencephalographical findings. The study population consisted of 47 epilepsy patients (38.3% female, n=18). The median age at the time of the scan was 40 years (range 12-81 years). Twenty-one out of 47 MRI scans (44.7%) showed coexisting lesions in the initial MRI evaluation; in 38.3% (n=18) of patients, those lesions were considered probably epileptogenic. After postprocessing, probable epileptogenic lesions were identified in 53.2% (n=25) of patients. Malformations of cortical development had initially been reported in 17.0% (n=8) of patients with TEs, which increased to 38.3% (n=18) after postprocessing. TEs and other epileptogenic lesions were considered equally epileptogenic in 21.3% (n=10) of the cases in the initial MR reports and 25.5% (n=12) of the cases after postprocessing. Temporal encephaloceles are a potential cause of MRI-negative temporal lobe epilepsy. According to our data, TEs can occur with other lesions, suggesting that increased awareness is also required in patients with lesional epilepsy. TEs may not always be epileptogenic; hence, their occurrence with other structural pathologies may influence the presurgical evaluation and surgical approach. Finally, TEs can be associated with malformations of cortical development, which may indicate a common developmental etiology of those lesions.

Epidemiology and Risk Factors of Convulsive Status Epilepticus Patients Admitted in the Emergency Department of Tertiary Hospital in Mogadishu, Somalia.

Status epilepticus (SE) is one of the most common neurologic emergencies and is associated with significant morbidity and mortality. The underlying cause of SE varies between patients with epilepsy and those presenting without. The aim of this study was to evaluate the epidemiology, risk factors and outcomes of patients presenting with convulsive SE in the emergency department (ED) of a tertiary hospital in Mogadishu. This was a cross-sectional study conducted between July 2021 and June 2022. The study included both patients with epilepsy and those without epilepsy presenting to the ED with SE. Risk factors and underlying etiologies were evaluated in the patients in both the pediatric group (0-18 years) and adult group (18 years and above).Clinical history, neurologic examinations, neuroimaging, electroencephalography findings, and laboratory investigations were all evaluated. The mean age for pediatric patients was 6 (SD±4.7), while the mean age for adult patients was 38 (SD±10.4). About 33 (36%) of the subjects had previous history of epilepsy, while 59 (64%) presented to the ED with their first seizure. About 80 (87%) had generalized seizure while 12 (13%) had focal seizure. Poor antiepileptic compliance was the most common risk factor for SE 20 (21.7%), followed by CNS infections 14 (15%), and prolonged febrile seizures 7 (7.6%). Poor antiepileptic drug compliance, cerebrovascular disorders, electrolyte imbalance, metabolic conditions, and drug abuse were the most common underlying etiologies of SE in patients older than 18 years. Prolonged febrile seizure, meningitis, encephalitis, systemic infections, and structural brain abnormalities were the most common underlying etiologies of SE in patients younger than 18 years. CNS infections, CVDs, metabolic disturbances, electrolyte imbalances, and systemic infections are major etiological risk factors of SE in patients without prior history of epilepsy. Medication adherence was the major etiological risk factor for SE identified in patients with epilepsy.

A DESCRIPTIVE STUDY OF EPILEPTIC PATIENTS IN HERAT CITY OF AFGHANISTAN

Epilepsy is one of the most common and serious neurological disorders which is characterized by recurrent unprovoked seizures. Its prevalence ranges from 0.5% to 1% of the population in developed countries, and even higher in developing countries. Around 70 million people worldwide have epilepsy.This research aims to perform a descriptive study on epileptic children 7-18 years old in Herat city of Afghanistan.This descriptive study was performed on 7-18 years old children with epilepsy, which was conducted from in 2021 in Herat city of Afghanistan. The study included 100 patients with epileptic disorders, in this study Encephalography, Magnetic resonance imaging, Computed tomography, and Sociodemographic information were used to describe the patients.The main group of this study included 100 epileptic children. The age of study participants ranged from 7- 18 years and the mean age was 9.21 ± 2.64 years.&nbsp;46 (51.1%) were males and 44 (48.9%) were females. More often Epilepsy cases were observed in patients with focal seizures. Hereditary predisposition was found as a risk factor and it was statistically significant, the p-value was less than 0.0007. Having status epilepsy was also found a risk factor for epilepsy and the p-value was 0.001. Also, prognostic factors for refractory epilepsy were determined in this study.The risk factors that were found in epileptic patients, were high and comparable with other studies in the world literature. More often epilepsy cases were determined in patients with focal seizures, hereditary predisposition, and having status epilepsy also found as prevalent risk factors for refractory epilepsy. Also, prognostic factors for epilepsy were identified. Negative factors were a high number of seizures, abnormal electroencephalography findings, and early onset of seizures in epileptic patients.

First Successful Application of Preimplantation Genetic Diagnosis for Lethal Neonatal Rigidity and Multifocal Seizure Syndrome in Korea: A Case Report

Lethal neonatal rigidity and multifocal seizure syndrome (RMFSL) is a severe autosomal recessive epileptic encephalopathy characterized by rigidity, intractable multifocal seizures, microcephaly, apnea, and bradycardia immediately after birth. RMFSL is related to a mutation in breast cancer 1-associated ataxia telangiectasia mutated activation-1 protein (BRAT1). We report a case of a female infant born to non-consanguineous Korean parents who developed hypertonia, dysmorphic features, progressive encephalopathy with refractory seizures at birth, and worsening intermittent apnea, leading to intubation and death at 137 days of age. The initial repeated electroencephalographic findings were normal; however, a pattern of focal seizures emerged at 35 days of life. Rapid trio whole-exome sequencing revealed heterozygous mutations c.1313_1314delAG p.(Gln438Argfs*51) and c.1276C&gt;T p. (Gln426*) in BRAT1. After genetic counseling for pregnancy planning, a preimplantation genetic diagnosis for targeted BRAT1 mutations was successfully performed, and a healthy baby was born. To our knowledge, this is the first reported case of a Korean patient with compound heterozygous mutations in BRAT1. An early and accurate genetic diagnosis can help provide timely treatment to patients and indicate the need for reproductive counseling for parents for family planning.

Relationship of loudness-dependent auditory evoked potentials with change-related cortical responses

Previous studies have suggested that change-related cortical responses are phenomena similar to the onset response and could be applied to the loudness dependence of auditory evoked potential (LDAEP) paradigm. In the present study, we examined the relationship between LDAEP and the change-related response using electroencephalography findings in 50 healthy subjects. There were five conditions (55, 65, 75, 85, and 95 dB) for LDAEP and five similar conditions (abrupt sound pressure increase from 70 to 75, 80, 85, 90, and 95 dB) for the change-related response. Both the onset and abrupt sound pressure increase evoked a triphasic response with peaks at approximately 50 (P50), 100 (N100), and 200 (P200) ms. We calculated the peak-to-peak amplitudes for P50/N100 and N100/P200. Medians and slopes for P50/N100 and N100/P200 amplitudes were calculated and compared between the two measures. Results revealed a significant correlation for both the slope and median for P50/N100 (r = 0.36, 0.37, p = 1.0 × 10-2, 7.9 × 10-3), N100/P200 (r = 0.40, 0.34, p = 4.0 × 10-3, 1.6 × 10-2), and P50/N100/P200 (r = 0.36, 0.35, p = 1.0 × 10-2, 1.3 × 10-2). These results suggested that the change-related response and LDAEP shared generation mechanisms at least partially.

Clinical profile of a cohort of neonates with seizures: Association between semiology, etiology, and electroencephalographic findings.

Seizures are the most common sign of neurologic dysfunction, reflecting a wide variety of central nervous system disorders. A retrospective cross-sectional study of neonates with a clinical diagnosis of seizures was conducted in order to verify relationships between clinical aspects and EEG findings. Patients were divided into 3 groups according to the EEG recording available as: 1) with confirmatory ictal EEG; 2) with altered but non-ictal EEG; and 3) without any EEG recording. Variables related to pregnancy and birth history, neonatal complications, and seizure semiology (by video or clinical description) were compared to EEG findings. 97 neonates were included (39.1% preterm, 54.6% male), 71 with available EEG data (56.3% with ictal EEG). The group without EEG presented clinical characteristics significantly different from the others such as extreme prematurity, low birth weight, and higher neonatal mortality (P = 0.002, 0.001, and 0.003, respectively). The most common etiology was hypoxic-ischemic encephalopathy (HIE) (46.4%) followed by vascular disorders, which predominated in extremely preterm neonates (P = 0.006). Sequential seizure was the most common type (44.6%) and was more frequently identified in term neonates (46%). In 51.2% of the ictal recordings the main finding was electrographic seizure without clinical manifestation. Discharge using antiseizure medication was higher among those with ictal or altered non-ictal EEG (P < 0.001). HIE is still a frequently etiology for neonatal seizures. Even if the patients in the sample were not under continuous EEG, the substantial proportion of electrographic seizures without clinical manifestations detected suggests the importance of continuous EEG monitoring in neonates at increased risk of seizures.

Determining the Relationship Between EEG Findings and Prognosis of Patients with Decreased Consciousness Following Head Injury

Background: Head injury is a silent epidemic in developed countries and is one of the leading causes of death and disability. Determining the precise and early prognosis of head injury, especially in severe cases, is essential and will help define treatment actions and rehabilitation plans and counsel other family members. The purpose of this study was to determine the relationship between electroencephalographic findings and prognosis in patients with decreased levels of consciousness due to head injury. Methods: This is a retrospective descriptive-analytical study on patients with reduced levels of consciousness due to head injury, referred to Tir Hospital (Tehran) in the first half of 2018. Overall, 52 patients were studied and divided according to their GCS into two groups: favorable prognosis (30 patients, 57.7%) and poor prognosis (22 patients, 42.3%). We tried to find the relation between EEG findings such as voltage, electrographic seizures, periodic and rhythmic patterns, and the prognosis. Results: Normal voltage was associated with a favorable prognosis, with a high specificity (95%) and a less robust sensitivity (63%). The isoelectric voltage (electrocerebral shutdown) was associated with a poor prognosis. Normal and isoelectric voltages were good predictors with 95% and 100% Positive Predictive Values (PPV), respectively. There was a statistically significant relationship between EEG frequency range and prognosis. Conclusion: This study showed that EEG parameters might provide valuable data regarding the prognosis of decreased consciousness of patients with a head injury, also for the guidance of physicians and informing the patients’ family.

Cnpy32xHA mice reveal neuronal expression of Cnpy3 in the brain

BackgroundIdentification of biallelic CNPY3 mutations in patients with epileptic encephalopathy and abnormal electroencephalography findings of Cnpy3 knock-out mice have indicated that the loss of CNPY3 function causes neurological disorders such as epilepsy. However, the basic property of CNPY3 in the brain remains unclear. New methodWe generated C-terminal 2xHA-tag knock-in Cnpy3 mice by i-GONAD in vivo genome editing system to investigate the expression and function of Cnpy3 in the mouse brain. Results2xHA-tagged Cnpy3 was confirmed by immunoblot analysis using anti-HA and CNPY3 antibodies, although HA tagging caused the decreased Cnpy3 protein level. Immunohistochemical analysis of Cnpy32xHA knock-in mice showed that Cnpy3-2xHA was predominantly expressed in the neuron. In addition, Cnpy3 and Cnpy3-2xHA were both localized in the endoplasmic reticulum and synaptosome and showed age-dependent expression changes in the brain. Comparison with existing methodsConventional Cnpy3 antibodies could not allow us to investigate the distribution of Cnpy3 expression in the brain, while HA-tagging revealed the expression of CNPY3 in neuronal cells. ConclusionsTaken together, we demonstrated that Cnpy32xHA knock-in mice would be useful to further elucidate the property of Cnpy3 in brain function and neurological disorders.

Electroencephalography Findings in Traumatic Brain Injury

Traumatic Brain Injury (TBI) or also known as a head injury is one of the leading causes of death among young people and is also one of the health problems defined as impact, penetration, and rapid movement of the brain within the skull that can result in changes in mental status and is often referred to as the silent epidemic. Head injuries can also result in electrophysiological abnormalities seen on electroencephalography (EEG) recordings. Electroencephalography was the first clinical neurodiagnostic assessment to reveal abnormal brain function after a head injury. For detecting brain injury, EEG may be more sensitive than clinical neurologic examination. In general conditions, electroencephalography is performed on patients with moderate to severe head injuries to provide information about the severity of the head injury, and establish a diagnosis of non-convulsive status epilepticus. This diagnosis often follows head injuries because patients with loss of consciousness are difficult to identify without an EEG examination. This also helps determine a prognosis for recovery and the likelihood of post-traumatic seizures. Electroencephalography features in head injuries depend on the severity of the injury and the location of the head itself. Electroencephalography after head injury shows slowing of the posterior dominant rhythm and increasing diffuse theta slowing, which returns to normal within hours or may subside more slowly over several weeks. Electroencephalography changes are not the same in each individual, due to differences in the severity of head injuries. It is important to know that there is no clear or specific EEG for mild traumatic brain injury.

Characteristic features of electroencephalogram in a pediatric patient with GRIN1 encephalopathy

BackgroundThe number of reports on GRIN1 variants associated with neurodevelopmental phenotypes has increased in recent years. However, there are only two detailed reports on electroencephalography findings. Case studyWe had a case with severe global developmental delay, and exome sequencing revealed a novel de novo heterozygous variant of GRIN1. The patient's electroencephalography showed unique findings: paroxysmal fast activity—20–30 Hz beta waves, independently in the bilateral occipital regions, sometimes in a continuous manner—and prolonged alpha activity in the bilateral frontal regions, observed mainly during sleep, those findings were observed persistently. DiscussionThe electroencephalography findings of our case have not been reported in the past. Receptor hypofunction due to the GRIN1 variant and imbalance in excitatory/inhibitory transmission owing to the dysfunction of the N-methyl-D-aspartate receptors may be the mechanism for the global developmental delay, stereotyped movements, and development of paroxysmal fast activity in our case. Accumulation of additional case reports is needed to confirm the reproducibility of the electroencephalography findings for disease specificity.

The Prevalence and Clinical Characteristics of Primary Stabbing Headache.

Objective: This study aimed to determine the prevalence and characteristics of primary stabbing headache in children and adolescents that presented because of headache. Materials and Methods: The medical files of 772 children and adolescents who presented with headache to the Pediatric Neurology Outpatient Clinic at Başkent University between 2012 and 2020 were retrospectively reviewed. In total, 77 patients (9.97%) with primary stabbing headache and those thought to have primary stabbing headache were included in the study. Patient data, including demographic features, headache characteristics, family history of primary headache, electroencephalographic (EEG) findings, and cranial magnetic resonane imaging (MRI) findings, were noted. Results: Age at presentation was <6 years in 16.9% of the patients and onset time of headache was below 3 months in 55.8%. Daily headache attacks occurred in 46.8% of the patients. Headache localization was frontal in 54.5% of patients and bilateral in 68.8%, whereas the quality of headache was undefined in 40.3%. Headache attack duration was seconds long in 37.7% of the patients, attacks occurred at any time of the day in 83.1%, and 80.5% did not have accompanying symptoms. In all, 54.5% of the patients had a negative family history of primary headache. In 95.8% of the patients, EEG findings were normal and cranial MRI findings were normal in 100% of the patients. Conclusion: The prevalence of primary stabbing headache is not rare in children and adolescents. Clinician awareness of the diagnosis and underlying causes of primary stabbing headache should be increased.

EEG Markers of Treatment Resistance in Idiopathic Generalized Epilepsy: From Standard EEG Findings to Advanced Signal Analysis.

Idiopathic generalized epilepsy (IGE) represents a common form of epilepsy in both adult and pediatric epilepsy units. Although IGE has been long considered a relatively benign epilepsy syndrome, a remarkable proportion of patients could be refractory to treatment. While some clinical prognostic factors have been largely validated among IGE patients, the impact of routine electroencephalography (EEG) findings in predicting drug resistance is still controversial and a growing number of authors highlighted the potential importance of capturing the sleep state in this setting. In addition, the development of advanced computational techniques to analyze EEG data has opened new opportunities in the identification of reliable and reproducible biomarkers of drug resistance in IGE patients. In this manuscript, we summarize the EEG findings associated with treatment resistance in IGE by reviewing the results of studies considering standard EEGs, 24-h EEG recordings, and resting-state protocols. We discuss the role of 24-h EEG recordings in assessing seizure recurrence in light of the potential prognostic relevance of generalized fast discharges occurring during sleep. In addition, we highlight new and promising biomarkers as identified by advanced EEG analysis, including hypothesis-driven functional connectivity measures of background activity and data-driven quantitative findings revealed by machine learning approaches. Finally, we thoroughly discuss the methodological limitations observed in existing studies and briefly outline future directions to identify reliable and replicable EEG biomarkers in IGE patients.

Description and Outcome of Severe Hypoglycemic Encephalopathy in the Intensive Care Unit.

Disorders of consciousness due to severe hypoglycemia are rare but challenging to treat. The aim of this retrospective cohort study was to describe our multimodal neurological assessment of patients with hypoglycemic encephalopathy hospitalized in the intensive care unit and their neurological outcomes. Consecutive patients with disorders of consciousness related to hypoglycemia admitted for neuroprognostication from 2010 to 2020 were included. Multimodal neurological assessment included electroencephalography, somatosensory and cognitive event-related potentials, and morphological and quantitative magnetic resonance imaging (MRI) with quantification of fractional anisotropy. Neurological outcomes at 28days, 3months, 6months, 1year, and 2years after hypoglycemia were retrieved. Twenty patients were included. After 2years, 75% of patients had died, 5% remained in a permanent vegetative state, 10% were in a minimally conscious state, and 10% were conscious but with severe disabilities (Glasgow Outcome Scale-Extended scores 3 and 4). All patients showed pathologic electroencephalography findings with heterogenous patterns. Morphological brain MRI revealed abnormalities in 95% of patients, with various localizations including cortical atrophy in 65% of patients. When performed, quantitative MRI showed decreased fractional anisotropy affecting widespread white matter tracts in all patients. The overall prognosis of patients with severe hypoglycemic encephalopathy was poor, with only a small fraction of patients who slowly improved after intensive care unit discharge. Of note, patients who did not improve during the first 6months did not recover consciousness. This study suggests that a multimodal approach capitalizing on advanced brain imaging and bedside electrophysiology techniques could improve diagnostic and prognostic performance in severe hypoglycemic encephalopathy.

Prognostic Value of Preoperative and Postoperative Electroencephalography Findings in Pediatric Patients Undergoing Hemispheric Epilepsy Surgery

The seizure outcomes after hemispheric epilepsy surgery have been excellent, with 54%-90% of patients achieving long-term freedom from seizures. Similarly, the neuropsychological outcomes have been favorable. The prognostic value of pre- and postoperative electroencephalography (EEG) has not been well-studied. In the present study, we characterized the value of the pre- and postoperative EEG findings for predicting the seizure and neuropsychological outcomes for pediatric patients undergoing hemispherectomy. A total of 22 children who had undergone functional hemispherectomy at our institution from 2010 to 2020 were included. The ictal and interictal findings were categorized as ipsilateral to the operated hemisphere, independently arising from the contralateral hemisphere, and/or generalized. The seizure outcomes were classified using the Engel scale. All neuropsychological evaluations were performed in accordance with our institution's protocol. The relationship between the EEG findings and outcomes was analyzed. Of the 22 patients, 19 (86%) were seizure free (Engel class IA) at the latest follow-up (mean, 4.2 years). On the preoperative EEGs, 9 had had seizures, all had had ipsilateral interictal discharges, and 9 had had contralateral interictal discharges. On the postoperative EEGs, obtained a median of 1 year after surgery, 3 had had seizures, 16 had had ipsilateral interictal discharges, and 5 had had contralateral interictal discharges. Of the 3 patients with seizures found on the postoperative EEG, all were clinically free of seizures. The patients who had not achieved Engel class IA were not significantly more likely to have abnormalities found on the EEG. The neuropsychological scores were stable from before to after surgery, with no evidence of EEG abnormalities having predictive value. The seizure and neuropsychology outcomes after hemispherectomy were excellent in our study, with 86% of our cohort achieving freedom from seizures. The presence, lateralization, and evolution of pre- and postoperative EEG abnormalities were not predictive of the outcomes.

The cognitive functions and seizure outcomes of patients with low-grade epilepsy-associated neuroepithelial tumors.

The aim of the study was to evaluate the cognitive functions and seizure outcomes of patients with low-grade epilepsy-associated neuroepithelial tumors (LEATs). We retrospectively reviewed the clinical data of patients who underwent preoperative neuropsychological evaluations and subsequent epilepsy surgery for LEATs. The neuropsychological results of full-scaled intelligence quotient (FSIQ) and full-scaled memory quotient (FSMQ) were analyzed, as well as the postoperative seizure outcomes. Of the 138 patients included in the study, 59 patients (40.4%) were female and 47 (36.6%) patients were children. Preoperatively, 138 patients received FSIQ assessments and 30 patients (21.7%) had an intellectual deficit (FSIQ < 80 scores); 124 patients received FSMQ assessments and 32 patients (25.8%) had a memory deficit (FSMQ < 80 scores). Younger age at seizure onset (OR 0.93; P = 0.035) and discordant ictal electroencephalography (EEG) findings (OR 5.26; P = 0.001) were found to predict intellectual deficits, while abnormal hippocampus (OR 2.36; P = 0.051) as well as discordant ictal EEG findings (OR 4.03; P = 0.007) tended to cause memory deficits. During postoperative follow-up, 123 patients (90.7%) were followed up at least 12months, and among them, 105 patients (85.4%) got seizure-free (Engel class I), while 18 patients (14.6%) were not (Engel class II-IV); longer duration of epilepsy (OR 1.01; P < 0.001) and discordant interictal EEG findings (OR 5.91; P = 0.005) were found to be related to poor seizure outcomes in patients with LEATs. Cognitive deficits commonly occur in patients with LEATs, especially in patients with early or childhood seizures. Early surgical intervention, however, could prevent most of patients from repeated seizure onsets and thus cognitive impairments.

TH-113. Alternating patterns in EEG recordings in patients with encephalopathy: Description of clinical and electroencephalographic findings

TH-113. Alternating patterns in EEG recordings in patients with encephalopathy: Description of clinical and electroencephalographic findings