The effect of SEEG on the long-term outcomes of different side anterior temporal lobectomy: A single-center retrospective study.

PURPOSE: Anterior temporal lobectomy (ATL) is the most common surgical treatment for temporal lobe epilepsy (TLE), and Stereoelectroencephalography (SEEG) plays a critical role in precisely localizing the epileptogenic zone (EZ). This study aimed to explore the effect of SEEG on the long-term outcomes of different side ATL. METHODS: From March 2012 to February 2020, a retrospective analysis was conducted on 231 TLE patients who underwent standard ATL surgery. According to the surgical sides and the utilization of SEEG during preoperative evaluation, the patients were categorized into four groups, with a follow-up period exceeding two years. RESULTS: Among the 231 TLE patients, the probability of being seizure-free two years after the surgery was 80.52%, which decreased to 65.65% after five years. There was no significant difference in outcomes between SEEG and non-SEEG patients. For overall and non-SEEG patients, there was no significant difference in short-term outcomes between different surgical sides. However, the long-term outcomes of right ATL patients were significantly better than left. Interestingly, for patients who underwent SEEG, there was no significant difference in both short-term and long-term outcomes between different surgical sides. CONCLUSION: Some TLE patients encounter challenges in localizing the EZ through non-invasive evaluation, necessitating the use of SEEG for precise localization. Furthermore, their seizure outcomes after surgery can be the same with the patients who have a clear epileptogenic zone in non-invasive evaluation. And SEEG patients can achieve a more stable long-term prognosis than non-SSEEG patients.

The long-term outcomes in drug-resistant epilepsy patients who underwent subtotal hemispherotomy: A single-center retrospective cohort study.

OBJECTIVE: To evaluate the long-term outcomes of subtotal hemispherotomy (SH) in treating drug-resistant epilepsy caused by unilateral hemispheric lesions and try to give the prognostic factors for these outcomes. METHODS: We retrospectively reviewed the clinical data of 19 patients who underwent SH in Sanbo Brain Hospital, Capital Medical University, Beijing, China, from May 2008 to April 2021. All clinical data and factors related to surgical and functional outcomes, including motor, neuropsychiatric, and language function, were collected and analyzed. RESULTS: The surgical outcomes showed 13 (68 %) patients were seizure-free at the last follow-up (2-14 years, mean: 5.6±2.9). No changes were found in motor outcomes in 12 (63 %) patients; seven (37 %) patients had new permanent motor deficits (NPMD). Improvement in the full-scale intelligence quotient (FIQ) (p = 0.009) was observed. Univariate analysis found that patients who did not achieve seizure freedom had a significantly older age at surgery (p = 0.017) and acute post-operative seizures (APOS) (p = 0.046). Kaplan-Meier analysis also identified significant differences in seizure outcomes between the children and adult subgroups (p = 0.0017). Multivariate Cox analysis showed that older age at surgery (HR=1.055, p = 0.034) was associated with shorter time-to-seizure-recurrence. Resection of the central operculum and insula (OR= 80.433, p =0.031) and higher monthly seizure frequency (OR= 1.073, p = 0.040) were also poor prognostic factors for motor function outcomes. CONCLUSION: SH is an effective treatment procedure in treating patients with drug-resistant epilepsy caused by hemispheric lesions with satisfied seizure outcomes, limited impairment of motor function, and preserving neuropsychiatric outcomes.

Spatiotemporal Neural Network for Sublexical Information Processing: An Intracranial SEEG Study.

Words offer a unique opportunity to separate the processing mechanisms of object subcomponents from those of the whole object, because the phonological or semantic information provided by the word subcomponents (i.e., sublexical information) can conflict with that provided by the whole word (i.e., lexical information). Previous studies have revealed some of the specific brain regions and temporal information involved in sublexical information processing. However, a comprehensive spatiotemporal neural network for sublexical processing remains to be fully elucidated due to the low temporal or spatial resolutions of previous neuroimaging studies. In this study, we recorded stereoelectroencephalography (SEEG) signals with high spatial and temporal resolutions from a large sample of 39 epilepsy patients (both sexes) during a Chinese character oral reading task. We explored the activated brain regions and their connectivity related to three sublexical effects: phonological regularity (whether the whole character's pronunciation aligns with its phonetic radical), phonological consistency (whether characters with the same phonetic radical share the same pronunciation), and semantic transparency (whether the whole character's meaning aligns with its semantic radical). The results revealed that sublexical effects existed in the inferior frontal gyrus, precentral and postcentral gyri, temporal lobe, and middle occipital gyrus. Additionally, connectivity from the middle occipital gyrus to the postcentral gyrus and from postcentral gyrus to the fusiform gyrus was associated with the sublexical effects. These findings provide valuable insights into the spatiotemporal dynamics of sublexical processing and object recognition in the brain.Significance statement Elucidating the intricate neural mechanisms underlying sublexical processing is crucial for understanding the intricacies of language comprehension and object recognition in the human brain. This study employed intracranial stereoelectroencephalography (SEEG) recordings to investigate the spatiotemporal dynamics of sublexical processing during a Chinese character reading task. We constructed a neural network for sublexical processing and depicted its temporal sequence in different brain regions. Furthermore, we identified the information flow within this network and observed its variation with the reading of characters containing different sublexical information. These findings not only advance our understanding of the cerebral mechanisms governing sublexical processing but also offer insights into the broader framework of object recognition processes.

Clinical characteristics and detection of MYB-QKI fusions in patients with angiocentric glioma.

PURPOSE: Angiocentric glioma (AG), a benign tumor identified within the last two decades, was officially included in the 2007 WHO Classification of Tumors of the Central Nervous System, WHO grade I. The tumor is relatively rare, with only approximately 100 cases reported. We aim to complement the characteristics and long-term prognosis of AG, as well as to detect MYB-QKI fusions. METHODS: The characteristics of all cases collected between 1 March 2009 and 1 March 2023 at the Beijing Sanbo Brain Hospital, Capital Medical University, were summarized and analyzed. Additionally, all fourteen patients were tested for MYB-QKI fusions. RESULTS: AG more predominantly occurs in adolescents (median age 16.5-year-old), and commonly presents with drug-resistant epilepsy. AG is frequently localized in the supratentorial regions and only one patient is in the brainstem. Brain parenchyma atrophy, and stalk-like signs can observe in imaging. Pathologically, tumor cells are perivascular pseudorosettes, presenting immunoreactivity for GFAP, S-100, Vimentin, "dot-like" staining for EMA, and low proliferative activity. Focal cortex dysplasia was observed in four patients. Twelve of fourteen (85.7%) patients were found with MYB-QKI fusions. Completely surgical resection typically has a satisfactory prognosis with long-term follow-up. CONCLUSION: AG is a rare benign tumor with a favorable prognosis after complete resection, characterized by refractory epilepsy, frequently occurring in adolescents. MYB-QKI fusions were detected in most AG patients, as a good defining genetic alteration pathologically. The potential presence of focal cortical dysplasia (FCD) may affect the prognosis of epilepsy.

Deep Brain Stimulation Inhibits Epileptic Seizures via Increase of Adenosine Release and Inhibition of ENT1, CD39, and CD73 Expression.

Deep brain stimulation (DBS) of the anterior nucleus of the thalamus is an efficacious treatment option for patients with refractory epilepsy. Our previous study demonstrates that adenosine is a potential target of DBS for the treatment of epilepsy. Equilibrative nucleoside transporters-1 (ENT1) and ectonucleotidases (CD39, CD73) function as regulators of extracellular adenosine in the brain. It is unclear whether ENT1, CD39, and CD73 are involved in the mechanism of DBS for epilepsy. A total of 48 SD male rats were divided into four groups: control (naïve rats), Pilo (pilocarpine induced rats with epilepsy), DBS (rats with epilepsy treated with DBS for 8 weeks), and sham. In the present study, video electroencephalogram monitoring, Morris water maze assays, in vivo measurements of adenosine using fiber photometry, histochemistry, and western blot were performed on the hippocampus. DBS markedly attenuated spontaneous recurrent seizures (SRSs) and enhanced spatial learning in rats with epilepsy, assessed through video-EEG and water maze assays. Fibred photometry measurements of an adenosine sensor revealed dynamic increase in extracellular adenosine during DBS. The expressions of ENT1, CD39, and CD73 in Pilo group and sham group increased compared with the control group, while the expressions of ENT1, CD39, and CD73 in DBS group decreased compared to that of Pilo group and sham group. The findings indicate that DBS reduces the number of SRSs and improves spatial memory in rats with epilepsy with concomitant decrease of ENT1, CD39, and CD73 expressions. Adenosine-modulating enzymes might be the potential targets of DBS for the treatment of epilepsy.

Seizure, Motor, and Cognitive Outcomes After Epilepsy Surgery for Patients With Sturge-Weber Syndrome: Results From a Multicenter Study.

BACKGROUND AND OBJECTIVES: Surgery is widely performed for refractory epilepsy in patients with Sturge-Weber syndrome (SWS), but reports on its effectiveness are limited. This study aimed to analyze seizure, motor, and cognitive outcomes of surgery in these patients and to identify factors associated with the outcomes. METHODS: This was a multicenter retrospective observational study using data from patients with SWS and refractory epilepsy who underwent epilepsy surgery between 2000 and 2020 at 16 centers throughout China. Longitudinal postoperative seizures were classified by Engel class, and Engel class I was regarded as seizure-free outcome. Functional (motor and cognitive) outcomes were evaluated using the SWS neurologic score, and improved or unchanged scores between baseline and follow-up were considered to have stable outcomes. Outcomes were analyzed using Kaplan-Meier analyses. Multivariate Cox regression was used to identify factors associated with outcomes. RESULTS: A total of 214 patients with a median age of 2.0 (interquartile range 1.2-4.6) years underwent surgery (focal resection, FR [n = 87]; hemisphere surgery, HS [n = 127]) and completed a median of 3.5 (1.7-5.0) years of follow-up. The overall estimated probability for being seizure-free postoperatively at 1, 2, and 5 years was 86.9% (95% CI 82.5-91.6), 81.4% (95% CI 76.1-87.1), and 70.7% (95% CI 63.3-79.0), respectively. The overall estimated probability of being motor stable at the same time post operatively was 65.4% (95% CI 58.4-71.2), 80.2% (95% CI 73.8-85.0), and 85.7% (95% CI 79.5-90.1), respectively. The overall probability for being cognition stable at 1, 2, and 5 years was 80.8% (95% CI 74.8-85.5), 85.1% (95% CI 79.3-89.2), and 89.5% (95% CI 83.8-93.2), respectively. Both FR and HS were effective at ensuring seizure control. For different HS techniques, modified hemispherotomy had comparable outcomes but improved safety compared with anatomical hemispherectomy. Regarding FR, partial resection (adjusted hazard ratio [aHR] 11.50, 95% CI 4.44-29.76), acute postoperative seizure (APOS, within 30 days of surgery; aHR 10.33, 95% CI 3.94-27.12), and generalized seizure (aHR 3.09, 95% CI 1.37-6.94) were associated with seizure persistence. For HS, seizure persistence was associated with APOS (aHR 27.61, 9.92-76.89), generalized seizure (aHR 7.95, 2.74-23.05), seizure frequency ≥30 times/month (aHR 4.76, 1.27-17.87), and surgical age ≥2 years (aHR 3.78, 1.51-9.47); motor stability was associated with severe motor defects (aHR 5.23, 2.27-12.05) and postoperative seizure-free status (aHR 3.09, 1.49-6.45); and cognition stability was associated with postoperative seizure-free status (aHR 2.84, 1.39-5.78) and surgical age <2 years (aHR 1.76, 1.13-2.75). DISCUSSION: FR is a valid option for refractory epilepsy in patients with SWS and has similar outcomes to those of HS, with less morbidity associated with refractory epilepsy. Early surgical treatment (under the age of 2 years) leads to better outcomes after HS, but there is insufficient evidence that surgical age affects FR outcomes. These findings warrant future prospective multicenter cohorts with international cooperation and prolonged follow-up in better exploring more precise outcomes and developing prognostic predictive models. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that in children with SWS and refractory seizures, surgical resection-focal, hemispherectomy, or modified hemispherotomy-leads to improved outcomes.

Enrichment of oligodendrocyte precursor phenotypes in subsets of low-grade glioneuronal tumours.

Current histological classification of low-grade glioneuronal tumours does not adequately represent their underlying biology. The neural lineage(s) and differentiation stage(s) involved and the cell state(s) affected by the recurrent genomic alterations are unclear. Here, we describe dysregulated oligodendrocyte lineage developmental programmes in three low-grade glioneuronal tumour subtypes. Ten dysembryoplastic neuroepithelial tumours, four myxoid glioneuronal tumours and five rosette-forming glioneuronal tumours were collected. Besides a comprehensive characterization of clinical features, known diagnostic markers and genomic alterations, we used comprehensive immunohistochemical stainings to characterize activation of rat sarcoma/mitogen-activated protein kinase pathway, involvement of neuronal component, resemblance to glial lineages and differentiation blockage along the stages of oligodendrocyte lineage. The findings were further complemented by gene set enrichment analysis with transcriptome data of dysembryoplastic neuroepithelial tumours from the literature. Dysembryoplastic neuroepithelial tumours, myxoid glioneuronal tumours and rosette-forming glioneuronal tumours occur at different ages, with symptoms closely related to tumour location. Dysembryoplastic neuroepithelial tumours and myxoid glioneuronal tumours contain oligodendrocyte-like cells and neuronal component. Rosette-forming glioneuronal tumours contained regions of rosette-forming neurocytic and astrocytic features. Scattered neurons, identified by neuronal nuclei antigen and microtubule-associated protein-2 staining, were consistently observed in all dysembryoplastic neuroepithelial tumours and myxoid glioneuronal tumours examined, but only in one rosette-forming glioneuronal tumour. Pervasive neurofilament-positive axons were observed only in dysembryoplastic neuroepithelial tumour and myxoid glioneuronal tumour samples. Alterations in B-Raf proto-oncogene, serine/threonine kinase, fibroblast growth factor receptor 1, fibroblast growth factor receptor 3 and platelet-derived growth factor receptor alpha occurred in a mutually exclusive manner, coinciding with strong staining of phospho-p44/42 mitogen-activated protein kinase and low apoptotic signal. All dysembryoplastic neuroepithelial tumours, myxoid glioneuronal tumours and the neurocytic regions of rosette-forming glioneuronal tumours showed strong expression of neuron-glia antigen 2, platelet-derived growth factor receptor alpha (markers of oligodendrocyte precursor cells) and neurite outgrowth inhibitor-A (a marker of developing oligodendrocytes), but lacked the expression of oligodendrocyte markers ectonucleotide pyrophosphatase/phosphodiesterase family member 6 and myelin basic protein. Notably, transcriptomes of dysembryoplastic neuroepithelial tumours were enriched in oligodendrocyte precursor cell signature, but not in signatures of neural stem cells, myelinating oligodendrocytes and astrocytes. Dysembryoplastic neuroepithelial tumour, myxoid glioneuronal tumour and rosette-forming glioneuronal tumour resemble oligodendrocyte precursor cells, and their enrichment of oligodendrocyte precursor cell phenotypes is closely associated with the recurrent mutations in rat sarcoma/mitogen-activated protein kinase pathway.

Mental health and insomnia problems in healthcare workers after the COVID-19 pandemic: A multicenter cross-sectional study.

BACKGROUND: Healthcare workers (HCWs) are at increased risk of contracting coronavirus disease 2019 (COVID-19) as well as worsening mental health problems and insomnia. These problems can persist for a long period, even after the pandemic. However, less is known about this topic. AIM: To analyze mental health, insomnia problems, and their influencing factors in HCWs after the COVID-19 pandemic. METHODS: This multicenter cross-sectional, hospital-based study was conducted from June 1, 2023 to June 30, 2023, which was a half-year after the end of the COVID-19 emergency. Region-stratified population-based cluster sampling was applied at the provincial level for Chinese HCWs. Symptoms such as anxiety, depression, and insomnia were evaluated by the Generalized Anxiety Disorder-7, Patient Health Questionnaire-9, and Insomnia Severity Index. Factors influencing the symptoms were identified by multivariable logistic regression. RESULTS: A total of 2000 participants were invited, for a response rate of 70.6%. A total of 1412 HCWs [618 (43.8%) doctors, 583 (41.3%) nurses and 211 (14.9%) nonfrontline], 254 (18.0%), 231 (16.4%), and 289 (20.5%) had symptoms of anxiety, depression, and insomnia, respectively; severe symptoms were found in 58 (4.1%), 49 (3.5%), and 111 (7.9%) of the participants. Nurses, female sex, and hospitalization for COVID-19 were risk factors for anxiety, depression, and insomnia symptoms; moreover, death from family or friends was a risk factor for insomnia symptoms. During the COVID-19 outbreak, most [1086 (76.9%)] of the participating HCWs received psychological interventions, while nearly all [994 (70.4%)] of them had received public psychological education. Only 102 (7.2%) of the HCWs received individual counseling from COVID-19. CONCLUSION: Although the mental health and sleep problems of HCWs were relieved after the COVID-19 pandemic, they still faced challenges and greater risks than did the general population. Identifying risk factors would help in providing targeted interventions. In addition, although a major proportion of HCWs have received public psychological education, individual interventions are still insufficient.

Posterior cingulate epilepsy: Seizure semiology and intracranial electrical stimulation using SEEG.

PURPOSE: This study aimed to explore seizure semiology and the effects of intracerebral electrical stimulation on the human posterior cingulate cortex (PCC) using Stereoelectroencephalography (SEEG) to deepen our comprehension of posterior cingulate epilepsy (PCE). METHODS: This study examined the characteristics of seizures through video documentation, by assessing the outcomes of intracranial electrical stimulation (iES) during SEEG. We further identified the connection between the observed semiology and precise anatomical locations within the PCC subregions where seizure onset zones (SOZ) were identified. RESULTS: Analysis was conducted on 59 seizures from 15 patients recorded via SEEG. Behavioural arrest emerged as the predominant manifestation across the PCC subregions. Where ictal activity extended to both the mesial and lateral temporal cortex, automatism was predominantly observed in seizures originating from the ventral PCC (vPCC). The retrosplenial cortex (RSC) is associated with complex motor behaviour, with seizure discharges spreading to the temporal lobe. Seizures originating from the PCC include axial tonic and autonomic seizures. Only one case of positive clinical seizures was documented. High frequencies of iES within the PCC induced various clinical responses, categorised as vestibular, visual, psychological, and autonomic, with vestibular reactions primarily occurring in the dorsal PCC (dPCC) and RSC, visual responses in the left RSC, and autonomic reactions in the vPCC and RSC. CONCLUSION: The manifestations of seizures in PCE vary according to the SOZ and the patterns of seizure propagation. The occurrence of seizures induced by iES is exceedingly rare, indicating that mapping of the PCC could pinpoint the primary sector of PCC.

Predictors of seizure outcomes in stereo-electroencephalography-guided radio-frequency thermocoagulation for MRI-negative epilepsy.

Background: One-third of intractable epilepsy patients have no visually identifiable focus for neurosurgery based on imaging tests [magnetic resonance imaging (MRI)-negative cases]. Stereo-electroencephalography-guided radio-frequency thermocoagulation (SEEG-guided RF-TC) is utilized in the clinical treatment of epilepsy to lower the incidence of complications post-open surgery. Objective: This study aimed to identify prognostic factors and long-term seizure outcomes in SEEG-guided RF-TC for patients with MRI-negative epilepsy. Design: This was a single-center retrospective cohort study. Methods: We included 30 patients who had undergone SEEG-guided RF-TC at Sanbo Brain Hospital, Capital Medical University, from April 2015 to December 2019. The probability of remaining seizure-free and the plotted survival curves were analyzed. Prognostic factors were analyzed using log-rank tests in univariate analysis and the Cox regression model in multivariate analysis. Results: With a mean time of 31.07 ± 2.64 months (median 30.00, interquartile range: 18.00-40.00 months), 11 out of 30 patients (36.7%) were classified as International League Against Epilepsy class 1 in the last follow-up. The mean time of remaining seizure-free was 21.33 ± 4.55 months [95% confidence interval (CI) 12.41-30.25], and the median time was 3.00 ± 0.54 months (95% CI 1.94-4.06). Despite falling in the initial year, the probability of remaining seizure-free gradually stabilizes in the subsequent years. The patients were more likely to obtain seizure freedom when the epileptogenic zone was located in the insular lobe or with one focus on the limbic system (p = 0.034, hazard ratio 5.019, 95% CI 1.125-22.387). Conclusion: Our findings may be applied to guide individualized surgical interventions and help clinicians make better decisions.

Clinical and pathologic features of Sturge-Weber syndrome in patients with refractory epilepsy.

OBJECTIVES: We aimed to investigate the clinicopathologic features of and genetic changes in Sturge-Weber syndrome (SWS) in patients with refractory epilepsy. METHODS: Clinical data were retrospectively analyzed. H&E and immunohistochemistry were performed to assess pathologic changes. Targeted amplicon sequencing was applied to investigate the somatic GNAQ (c.548G>A) mutation. The potential predictors of seizure outcomes were estimated by univariate and multivariate statistical analyses. RESULTS: Forty-eight patients with SWS and refractory epilepsy were enrolled. According to the imaging data and pathologic examination, ipsilateral hippocampal sclerosis (HS), calcification of leptomeningeal arteries, and focal cortical dysplasia were found in 14 (29.2%), 31 (64.6%), and 37 (77.1%) patients, respectively. A high frequency of GNAQ alteration was detected in both cerebral cortex (57.7%) and ipsilateral hippocampus (50.0%) from patients with SWS. During follow-up, 43 of 48 patients (85.4%) had achieved seizure control (Engel class I). Statistically, HS signs on imaging were found to be independent predictors of unfavorable seizure outcomes (P = .015). CONCLUSIONS: Calcification of leptomeningeal arteries, focal cortical dysplasia, and GNAQ alteration are common features in SWS pathology. Patients with refractory epilepsy caused by SWS can achieve satisfactory seizure control after surgery, but seizure control was compromised in patients with comorbid HS.

COVID-19 vaccination for patients with epilepsy: A Chinese expert consensus.

Coronavirus disease-2019 (COVID-19) first emerged in late 2019 and has since spread worldwide. More than 600 million people have been diagnosed with COVID-19, and over 6 million have died. Vaccination against COVID-19 is one of the best ways to protect humans. Epilepsy is a common disease, and there are approximately 10 million patients with epilepsy (PWE) in China. However, China has listed "uncontrolled epilepsy" as a contraindication for COVID-19 vaccination, which makes many PWE reluctant to get COVID-19 vaccination, greatly affecting the health of these patients in the COVID-19 epidemic. However, recent clinical practice has shown that although a small percentage of PWE may experience an increased frequency of seizures after COVID-19 vaccination, the benefits of COVID-19 vaccination for PWE far outweigh the risks, suggesting that COVID-19 vaccination is safe and recommended for PWE. Nonetheless, vaccination strategies vary for different PWE, and this consensus provides specific recommendations for PWE to be vaccinated against COVID-19.

Ectopic expression of neuronal adenosine kinase, a biomarker in mesial temporal lobe epilepsy without hippocampal sclerosis.

AIMS: Mesial temporal lobe epilepsy without hippocampal sclerosis (no-HS MTLE) refers to those MTLE patients who have neither magnetic resonance imaging (MRI) lesions nor definite pathological evidence of hippocampal sclerosis. They usually have resistance to antiepileptic drugs, difficulties in precise seizure location and poor surgical outcomes. Adenosine is a neuroprotective neuromodulator that acts as a seizure terminator in the brain. The role of adenosine in no-HS MTLE is still unclear. Further research to explore the aetiology and pathogenesis of no-HS MTLE may help to find new therapeutic targets. METHODS: In surgically resected hippocampal specimens, we examined the maladaptive changes of the adenosine system of patients with no-HS MTLE. In order to better understand the dysregulation of the adenosine pathway in no-HS MTLE, we developed a rat model based on the induction of focal cortical lesions through a prenatal freeze injury. RESULTS: We first examined the adenosine system in no-HS MTLE patients who lack hippocampal neuronal loss and found ectopic expression of the astrocytic adenosine metabolising enzyme adenosine kinase (ADK) in hippocampal pyramidal neurons, as well as downregulation of neuronal A1 receptors (A1 Rs) in the hippocampus. In the no-HS MTLE model rats, the transition of ADK from neuronal expression to an adult pattern of glial expression in the hippocampus was significantly delayed. CONCLUSIONS: Ectopic expression of neuronal ADK might be a pathological hallmark of no-HS MTLE. Maladaptive changes in adenosine metabolism might be a novel target for therapeutic intervention in no-HS MTLE.

Protocol of a prospective multicenter randomized controlled trial of robot-assisted stereotactic lesioning in the treatment of focal drug-resistant epilepsy.

BACKGROUND: This protocol describes the design of a multicenter randomized controlled trial of robot-assisted stereotactic lesioning versus epileptogenic foci resection. Typical causes of focal epilepsy include hippocampal sclerosis and focal cortical dysplasia. These patients usually present with drug resistance and require surgical treatment. Although epileptogenic foci resection is still the most commonly used treatment for such focal epilepsy, there is increasing evidence that epileptogenic focus resection may lead to neurological impairment. The treatment of epilepsy with a robot-assisted stereotactic lesioning mainly includes two new minimally invasive surgical methods: radiofrequency thermocoagulation (RF-TC) and laser interstitial thermal therapy (LITT). Seizure-free is less likely to be achieved by these two procedures, but neurologic preservation is better. In this study, we aimed to compare the safety and efficacy of RF-TC, LITT, and epileptogenic foci resection for focal drug-resistant epilepsy. METHODS: This is a multicenter, three-arm, randomized controlled clinical trial. The study will include patients older than 3 years of age with epilepsy who have had medically refractory seizures for at least 2 years and are eligible for surgical treatment with an epileptogenic focus as determined by multidisciplinary evaluation prior to randomization. The primary outcome measure is seizure outcome (quantified by seizure remission rate) at 3-month, 6-month, and 1-year follow-up after treatment. Postoperative neurologic impairment, spectrum distribution change of video electroencephalogram, quality of life, and medical costs will also be assessed as secondary outcomes. TRIAL REGISTRATION: Chinese Clinical Trials Registry ChiCTR2200060974. Registered on June 14, 2022. The status of the trial is recruiting, and the estimated study completion date is December 31, 2024.

Aberrant adenosine signaling in patients with focal cortical dysplasia.

Focal cortical dysplasia (FCD), a common malformation of cortical development, is frequently associated with pharmacoresistant epilepsy in both children and adults. Adenosine is an inhibitory modulator of brain activity and a prospective anti-seizure agent with potential for clinical translation. Our previous results demonstrated that the major adenosine-metabolizing enzyme adenosine kinase (ADK) was upregulated in balloon cells (BCs) within FCD type IIB lesions, suggesting that dysfunction of the adenosine system is implicated in the pathophysiology of FCD. In our current study, we therefore performed a comprehensive analysis of adenosine signaling in surgically resected cortical specimens from patients with FCD type I and type II via immunohistochemistry and immunoblot analysis. Adenosine enzyme signaling was assessed by quantifying the levels of the key enzymes of adenosine metabolism, i.e., ADK, adenosine deaminase (ADA), and ecto-5'-nucleotidase (CD73). Adenosine receptor signaling was assessed by quantifying the levels of adenosine A2A receptor (A2AR) and putative downstream mediators of adenosine, namely, glutamate transporter-1 (GLT-1) and mammalian target of rapamycin (mTOR). Within lesions in FCD specimens, we found that the adenosine-metabolizing enzymes ADK and ADA, as well as the adenosine-producing enzyme CD73, were upregulated. We also observed an increase in A2AR density, as well as a decrease in GLT-1 levels and an increase in mTOR levels, in FCD specimens compared with control tissue. These results suggest that dysregulation of the adenosine system is a common pathologic feature of both FCD type I and type II. The adenosine system might therefore be a therapeutic target for the treatment of epilepsy associated with FCD.

SEEG-based reevaluation of epileptogenic networks and the predictive role for reoperation in MTLE patients with surgical failure.

OBJECTIVE: Approximately 20%-30% of mesial temporal lobe epilepsy (MTLE) patients got unfavorable seizure control after surgery, and there was a discrepancy about the reasons for the surgical failure. The functional connectivity (FC) patterns obtained from stereo-electroencephalography (SEEG) reveal information about the dynamics of the epileptic brain and the added value of extracting information that was not identifiable in the SEEG data using FC analysis. This study aims to find out the patterns of the potential epileptogenic network of failure patients and the electrophysiological predictors of reoperation. METHODS: From January 2012 to December 2019, the MTLE patients with surgical failure were reviewed, and all patients underwent SEEG-guided reoperation. The epileptogenic network was quantified by calculating FC indicators, including phase slope index (PSI), mutual information (MI) strength, imaginary coherence (icoh), and Granger causality. RESULTS: Ten patients with 13 seizures were included in the analysis, and 7 of them achieved a favorable outcome after the SEEG-guided reoperation. The surgical zone (SZ) with a favorable prognosis showed greater outward information flow than the non-SZ, whereas the SZ with an unfavorable prognosis showed greater inward information flow. The recurrent patients with favorable prognosis had strong connectivity between the posterior hippocampus, temporal neocortex, and insula, whereas the patients with unfavorable prognosis showed strong functional connectivity between the insula and temporal-parietal-occipital junction. The power spectrum of patients with favorable prognosis was significantly lower than that of patients with unfavorable prognosis, especially showing a more oscillation power of low frequency. SIGNIFICANCE: The SEEG-guided reoperation could achieve favorable seizure control outcomes for recurrent patients. The FCs were a potential indicator to help construct the temporal epileptic network and predictor for the reoperative prognosis in the recurrent patients.

The clinicopathological features of ganglioglioma with CD34 expression and BRAF mutation in patients with epilepsy.

Objective: The aim of the study was to evaluate the clinicopathological features, as well as the surgical prognosis, of epilepsy-associated gangliogliomas (GG) with CD34 expression and BRAFV600E mutation. Methods: Clinical data of patients who underwent epilepsy surgery for GG were retrospectively studied. Univariate and multivariate analyses were performed to evaluate the correlations of clinical and pathological factors with molecular markers of CD34 expression and BRAFV600E mutation in GG. Results: A total of 208 patients with GG had immunohistochemical detection of CD34 expression (positive/negative: 184/24), and among them, 89 patients had immunohistochemical detection of BRAFV600E mutation (positive/negative: 54/35). By univariate and multivariate analyses, seizure aura (p = 0.025), concordance of ictal electroencephalogram (EEG) findings (p = 0.045) and medial temporal tumor (p = 0.030) were found to be related to CD34 expression, but only hospitalization time (p = 0.042) was different for BRAF-mutated status. In addition, drug-resistant epilepsy (p = 0.040) and concordance of interictal EEG findings (p = 0.009) were found to be associated with tumor progression-free survival (PFS) in univariate analysis, but only concordance of interictal EEG findings was with significance in multivariate analysis. However, CD34 expression or BRAFV600E mutation in GG was not found to be associated with surgical outcomes of seizure control and tumor PFS. Conclusion: The CD34 expression or BRAFV600E mutation in GG may partly influence the distribution of clinicopathological features of patients with epilepsy, but they may be not able to predict the surgical prognosis of seizure outcome and tumor recurrence.

Long-term ANT-DBS effects in pilocarpine-induced epileptic rats: A combined 9.4T MRI and histological study.

Deep brain stimulation (DBS) of the anterior nucleus of the thalamus (ANT) appears to be effective against seizures in animals and humans however, its therapeutic mechanisms remain elusive. This study aimed to combine 9.4T multimodal magnetic resonance imaging (MRI) with histology to investigate the longitudinal effects of long-term ANT-DBS in pilocarpine-induced epileptic rats. Status epilepsy (SE) was induced by LiCl-pilocarpine injection in 11 adult male Sprague-Dawley rats. Four weeks after SE, chronic epileptic rats underwent either ANT-DBS (n = 6) or sham-DBS (n = 5) surgery. Electroencephalography (EEG) and spontaneous recurrent seizures (SRS) were recorded for 1 week. The T2-weighted image and images from resting-state functional MRI (rs-fMRI) were acquired at three states: before SE, at 4 weeks post-SE, and at 5 weeks post-DBS. Volumes of the hippocampal subregions and hippocampal-related functional connectivity (FC) were compared longitudinally. Finally, antibodies against neuronal nuclei (NeuN) and glial fibrillary acidic proteins were used to evaluate neuronal loss and astrogliosis in the hippocampus. Long-term ANT-DBS significantly reduced seizure generalization in pilocarpine-induced epileptic rats. By analyzing the gray matter volume using T2-weighted images, long-term ANT-DBS displayed morphometric restoration of the hippocampal subregions. Neuronal protection of the hippocampal subregions and inhibition of astrogliosis in the hippocampal subregions were observed in the ANT-DBS group. ANT-DBS caused reversible regulation of FC in the insula-hippocampus and subthalamic nucleus-hippocampus. Long-term ANT-DBS provides comprehensive protection of hippocampal histology, hippocampal morphometrics, and hippocampal-related functional networks.

The differential role of magnetic resonance imaging in predicting surgical outcomes between children versus adults with temporal lobe epilepsy.

Objective: This study aims to investigate the clinical discrepancies and the different predictors of anterior temporal lobectomy (ATL) in children (<18 years at surgery) and adults (>18 years at surgery) with temporal lobe epilepsy (TLE). Materials and methods: A total of 262 patients (56 children and 206 adults) with TLE who underwent ATL were included in this study. The clinical variables, including patients' characteristics, preoperative evaluations, pathology, surgical prognosis, and surgical predictors were assessed the discrepancies between TLE children versus adults using univariate and multivariate analyses. Kaplan-Meier survival analysis was used to calculate the probability of seizure freedom and AEDs withdrawal after ATL, and the difference between TLE children and adults was analyzed using the Log-Rank test. Results: There were significant differences including semiology, magnetic resonance imaging (MRI) examinations, numbers of preoperative AEDs, and pathologies between TLE children and adults (P < 0.05, Q < 0.05). The MRI-detected epileptic focus was the only independent predictor of seizure freedom (P = 0.002, Q = 0.036) in TLE children, and the concordance of MRI-detected focus with video-electroencephalography (video-EEG)-detected epileptic zone was the only variable associated with seizure freedom in TLE adults (OR = 2.686, 95% CI = 1.014-7.115, P = 0.047). The TLE children experienced a higher probability of AEDs withdrawal than adults after surgery (P = 0.005). Significance: There were remarkable differences in clinical manifestations, MRI examinations, number of preoperative AEDs, and pathologies between TLE children versus adults. TLE children had a higher possibility of AEDs withdrawal than adults after surgery. The favorable seizure outcome of ATL depended on the early complete resection of MRI-detected epileptogenic focus in TLE children, while the concordance of MRI-detected focus with EEG-detected epileptogenic zone was the only predictor of favorable seizure outcomes in TLE adults.

Effectiveness of vagus nerve stimulation therapy in refractory hypoxic-ischemic encephalopathy-induced epilepsy.

Background: Epilepsy is one of the important long-term sequelae of neonatal hypoxic-ischemic encephalopathy (HIE) and is typically characterized by drug resistance and poor surgical outcomes. Vagus nerve stimulation (VNS) is a promising neuromodulation therapy for refractory epilepsy. Objectives: The present study aimed to first evaluate the effectiveness of VNS in patients with refractory HIE-induced epilepsy and scrutinize potential clinical predictors. Methods: We retrospectively collected the outcomes of VNS in all patients with refractory HIE-induced epilepsy and at least 2 years of follow-up. Subgroups were classified as responders and nonresponders according to the effectiveness of VNS (⩾50% or <50% reduction in seizure frequency). Preoperative data were analyzed to screen for potential predictors of VNS effectiveness. Results: A total of 55 patients with refractory HIE-induced epilepsy who underwent VNS therapy were enrolled. Responders represented 56.4% of patients, and 12.7% of patients achieved seizure freedom at the last follow-up. In addition, the responder rate increased over time with rates of 23.6%, 38.2%, 50.9%, and 56.4% at the 3-, 6-, 12- and 24-month follow-ups, respectively. After multivariate analysis, neonatal seizure was identified as a negative predictor (OR: 4.640, 95% CI: 1.129-19.066), and a predominant seizure type of generalized onset was identified as a positive predictor (OR: 0.261, 95% CI: 0.078-0.873) of VNS effectiveness. Conclusion: VNS therapy was effective in patients with refractory HIE-induced epilepsy and was well tolerated over a 2-year follow-up period. VNS therapy demonstrated better effectiveness in patients without neonatal seizures or with a predominant seizure type of generalized onset.