Epilepsia Open最新文献

Objective

Clinical studies indicated a link between DTI imaging characteristics and epilepsy, but the causality of this connection had not been established. Therefore, we employed the Mendelian randomization analysis method to determine the causal relationship between DTI imaging characteristics and epilepsy.

Method

We used Mendelian randomization analysis to identify the causal relationship between brain structure and the risk of epilepsy. GWAS data of DTI phenotypes, focal epilepsy, and genetic generalized epilepsy (GGE) were utilized in the analysis.

Results

Our study found that DTI imaging phenotypes had a causal risk relationship with epilepsy. These phenotypes had a statistical impact on the risk of epilepsy seizures. There were differences in DTI phenotype causality between GGE and focal epilepsy, which were associated with the clinical phenotype differences of the two types of epilepsy.

Significance

Our study demonstrated that the diagnosis of subtypes could be assisted by comparing the differences in DTI phenotypes of specific brain regions. This meant that by studying the changes in brain regions before the onset of epilepsy, we might be able to intervene in epilepsy at an earlier stage.

Plain Language Summary

Our study used Mendelian randomization to explore the causal relationship between brain structure, as seen in DTI imaging, and epilepsy. We found that specific DTI phenotypes are linked to an increased risk of epilepsy seizures, with notable differences between genetic generalized epilepsy and focal epilepsy. This suggested that analyzing DTI phenotypes could help in diagnosing and potentially intervening in epilepsy earlier by finding brain changes before seizures begin.

Objective

Cortical atrophy close to medial temporal structures has been described consistently in patients with temporal lobe epilepsy (TLE). Successful TLE surgery may have a neuroprotective effect preventing further atrophy of temporal and extratemporal cortex. However, the effects of epilepsy surgery on subcortical structures demand additional enlightenment. This work aimed to determine how epilepsy surgery affects volumes of subcortical structures in medically refractory temporal lobe epilepsy patients.

Methods

We compared MRI volumes of subcortical structures in 62 patients with TLE (36 left, 26 right) before and after anterior temporal lobectomy with 38 TLE patients (20 left, 18 right) who were considered to be good surgical candidates and had at least two brain MRIs.

Results

There were no volume differences in subcortical structures on preoperative and initial MRIs of non-operated TLE patients. At baseline, the ipsilateral thalamus and putamen in TLE patients were marginally smaller than contralateral structures. Operated patients showed a significant postoperative volume reduction in ipsilateral thalamus, putamen, and globus pallidus. In contrast, there were no significant volumetric reductions in non-operated patients longitudinally. There were no volumetric changes associated with different surgical outcomes or different postoperative cognitive outcomes.

Significance

Our study demonstrated postoperative volume loss of thalamus, putamen and globus pallidus ipsilaterally to the side of resection. Our findings suggest surgery-related changes, likely Wallerian degeneration within subcortical networks not related to seizure or cognitive outcome.

Plain Language Summary

We studied 100 patients with epilepsy, comparing those who had surgery to those who did not. After surgery, the thalamus, putamen and globus pallidus on the same side as the surgery shrank significantly, but not in non-surgery patients. This suggests surgery-related changes in deeper brain structures, unrelated to seizure freedom or cognitive outcomes. This research sheds additional light on the response of the subcortical structure to epilepsy surgery, highlighting potential areas for further study.

Introduction

Vagus nerve stimulation (VNS) is an effective treatment for people with drug-resistant epilepsy. However, its mechanisms of action are poorly understood, including which nerve fibers are activated in humans during VNS in typical clinical settings and which are required for clinical efficacy. In particular, there have been no intraneural recordings of vagus nerve fiber activation in awake humans undergoing chronic VNS. In this study, for the first time, we report recordings from the vagus nerve in this setting.

Methods

The recordings were performed using a sterile tungsten microelectrode inserted percutaneously into the cervical vagus nerve under ultrasound guidance. The clinical VNS systems were used to deliver stimulation while activity in the vagus nerve was recorded.

Results

In addition to activating myelinated axons at low currents, we provide evidence that VNS can also activate unmyelinated C fibers in the vagus nerve at currents <1 mA.

Conclusions

These results add to our understanding of how VNS exerts its beneficial effects in drug-resistant epilepsy.

Plain Language Statement

Here we describe for the first time, electrical recordings from the vagus nerve in awake drug-resistant epilepsy patients with an implanted vagus nerve stimulation (VNS) device. We found that the VNS device was able to activate both myelinated and unmyelinated fibers within the vagus nerve, which contributes to our understanding of how VNS works in the context of drug-resistant epilepsy.

Molecular diagnosis for pediatric epilepsy patients can impact treatment and health supervision recommendations. However, there is little known about factors affecting the time to receive a diagnosis. Our objective was to characterize factors affecting the time from first seizure to molecular diagnosis in children with epilepsy. A retrospective, population-based review was used to analyze data from pediatric patients with a genetic etiology for epilepsy over a 5 year period. A subgroup of patients with seizure onset after 2016 was evaluated for recent trends. We identified 119 patients in the main cohort and 62 in a more recent (contemporaneous) subgroup. Sex, race, and ethnicity were not significantly associated with time to molecular diagnosis. A greater number of hospitalizations was associated with a shorter time to diagnosis (p < 0.001). Developmental delay was associated with a longer time to diagnosis (p = 0.002). We found no association for time to diagnosis with a diagnosis of autism, utilization of free genetic testing, or epilepsy type. In the recent subgroup analysis, commercial insurance was associated with decreased time to diagnosis (p = 0.02). Developmental delay, public insurance, or patients in the outpatient setting had longer times to molecular diagnosis. These findings suggest that there may be opportunities to implement interventions aimed at accelerating the provision of genetic testing in pediatric epilepsy.

Plain Language Summary

Genetic diagnosis for pediatric epilepsy patients can impact treatment and care. This study looked at factors that affect how long it takes a pediatric epilepsy patient to receive a genetic diagnosis. We found that sex, race and ethnicity, epilepsy type, and whether the patient had autism did not affect how long it took the patient to receive a diagnosis. However, we found that patients with developmental delay, fewer hospitalizations, and public insurance took a longer time to receive a diagnosis. Our findings suggest potential strategies for reducing the time to receive a genetic diagnosis.

Recent genetic studies have revealed that hemimegalencephaly (HME) is a multi-system disorder associated with germline or mosaic variants within the PI3K-mTOR-GATOR1 signaling pathways. Patients with HME typically develop drug-resistant epilepsy necessitating extensive evaluation, hemispherectomy, and long-term management. We describe the role of a multidisciplinary team (MDT) for the diagnosis and management of recent patients with HME at UCLA who underwent hemispherectomy. Genetic evaluation identified nine patients with the following variants: NPRL3 x2 germline, PIK3CA mosaicism x4, MTOR mosaicism x1, AKT3 mosaicism x1, unknown x1. Each patient's MDT comprised 4–9 specialties. One child with a MTOR variant had persistent epilepsy after hemispherectomy, but addition of everolimus resulted in an 80% decrease in seizure frequency. Another child with hemihypertrophy and PIK3CA mosaic variant was offered targeted PIK3CA inhibitor treatment, alpelisib, for overgrowth. A third child with germline NPRL3 variant inherited from their unaffected mother resulted in a sibling being diagnosed with the variant who later developed seizures secondary to focal cortical dysplasia. The implementation of a MDT offers essential guidance for families affected by HME, encompassing prognostication, surveillance, and therapeutic strategies. Identifying the etiology of HME can facilitate the development of targeted treatments and enable timely genetic counseling.

Plain Language Summary

Hemimegalencephaly (HME) is a complex brain disorder caused by genetic changes. It often leads to severe epilepsy that doesn't respond to standard treatments and frequently requires surgery. In this case series, nine patients with HME were identified and found to have genetic mutations in key growth-regulating genes. A multidisciplinary team model was developed to facilitate patients' care. For example, one patient's seizures improved with surgery, another with a new targeted medication, and another received treatment for symptoms of overgrowth. This team approach provides comprehensive care for patients and can lead to efficient care coordination and implementation of novel therapies.

Epilepsy is a prevalent neurological disease that impacts around 70 million individuals globally. Anti-seizure medications (ASMs) are the first choice for clinicians to control unprovoked epileptic seizures. Although more than 30 ASMs are available in the market, patients with epilepsy (PWEs) still show poor responses to adequate drug treatment. Meanwhile, long-term medications not only bring heavy financial burdens but also lead to undesirable side effects. Music, a ubiquitous art form throughout human history, has been confirmed as therapeutically effective in various neurological conditions, including epilepsy. This alternative therapy offers convenience and a relatively safe approach to alleviating epileptic symptoms. Paradoxically, besides anti-convulsant effect, some particular music would cause seizures inversely, indicating the pro-convulsant effect of it. Considering that investigating the impact of music on epilepsy emerges as a compelling subject. In this review, we tried to present the following sections of content on this topic. Initially, we overviewed the impact of music on the brain and the significant progress of music therapy in central neurological disorders. Afterward, we classified the anti-convulsant and pro-convulsant effects of music in epilepsy, relying on both clinical and laboratory evidences. Finally, possible mechanisms and neural basis of the music effect were concluded, and the translational potentials and some future outlooks about the music effect in epilepsy were proposed.

Plain Language Summary

Epilepsy is an extremely severe neurological disorder. Although anti-seizure medications are preferred choice to control seizures, the efficacy is not satisfied due to the tolerance. Anecdotal music effect had been deemed functional diversity but not clarified on epilepsy, pro-convulsive, or anti-convulsive. Here, we reviewed this interesting but puzzling topic, as well as illustrating the potential mechanisms and its translational potential.