Improved Seizure Control Research Articles

Deep brain stimulation of the anterior nucleus of the thalamus for drug‐resistant epilepsy: Long‐term efficacy and outcomes from a prospective cohort

AbstractAimThe anterior nucleus of the thalamus (ANT) has been one of the deep brain stimulation (DBS) targets for drug‐resistant epilepsy. This study aims to investigate the control of seizures among patients with ANT DBS for epilepsy. We have pioneered DBS for epilepsy in Hong Kong since 2015 and this study aims to report the long‐term outcomes from a prospective cohort.MethodsThis is a prospective cohort study of ANT DBS for adult patients with drug‐resistant epilepsy, who are unsuitable for resective epilepsy surgery.ResultsSix patients (3 females and 3 males, mean age 31.3) received bilateral ANT DBS in a tertiary university hospital from 2015 to 2018 (one in 2015, two in 2017 and three in 2018). Both frontal transventricular and parietal approaches were used. The active contacts were selected based on the closest Euclidean distance to the mammillothalamic tract and ANT junction. Five of the six cases (83.3%) achieved greater than 50% reduction in seizures after the operations. The median percentage of reduction in seizures was 58.5% at 3 years after DBS (range, 32.7%–80%). Overall, there was a trend of improving seizure control rate from year 1 to year 6 after the ANT DBS operations.ConclusionsThis is the first report of ANT DBS for drug‐resistant epilepsy in Hong Kong. The results are encouraging. ANT DBS for drug‐resistant epilepsy is effective and sustained in long term. The treatment option of ANT DBS should be considered in suitable candidates with drug‐resistant epilepsy in our locality.

Meningeal defects and focal cortical dysplasia: an unrecognized relationship? Illustrative case.

BACKGROUNDFocal cortical dysplasias (FCDs) are a heterogenous cluster of histopathologic entities classically associated with medically refractory epilepsy. Because there is substantial histopathologic variation among different types of FCD, there are likely multiple pathogenic mechanisms leading to these disorders. The meninges are known to play a role in cortical development, and disruption of meningeal-derived signaling pathways has been shown to impact neurodevelopment. To our knowledge, there has not yet been an investigation into whether genetic pathways regulating meningeal development may be involved in the development of FCD.OBSERVATIONSThe authors reported a patient with refractory epilepsy and evidence of FCD on imaging who received surgical intervention and was found to have an unusual dural anomaly overlying a region of type Ic FCD. To the authors’ knowledge, this was the first report describing a lesion of this nature in the context of FCD.LESSONSThe dural anomaly exhibited by the patient presented what could be a potentially novel pathogenic mechanism of FCD. Resection of the cortical tissue underlying the dural anomaly resulted in improvement in seizure control. Although the pathogenesis is unclear, this case highlighted the importance of further investigation into the developmental origins of FCD, which may help elucidate whether a connection between meningeal development and FCD exists.

Initial experience with magnetic resonance-guided focused ultrasound stereotactic surgery for central brain lesions in young adults.

Magnetic resonance-guided focused ultrasound (MRgFUS) is an incisionless procedure capable of thermoablation through the focus of multiple acoustic beams. Although MRgFUS is currently approved for the treatment of tremor in adults, its safety and feasibility profile for intracranial lesions in the pediatric and young adult population remains unknown. The long-term outcomes of a prospective single-center, single-arm trial of MRgFUS at Nicklaus Children's Hospital in Miami, Florida, are presented. Patients 15-22 years of age with centrally located lesions were recruited, clinically consistent with WHO grade I tumors that require surgical intervention. This cohort consisted of 4 patients with hypothalamic hamartoma (HH), and 1 patient with tuberous sclerosis complex harboring a subependymal giant cell astrocytoma (SEGA). In each case, high-intensity FUS was used to target the intracranial lesion. Real-time MRI was used to monitor the thermoablations. Primary outcomes of interest were tolerability, feasibility, and safety of FUS. The radiographic ablation volume on intra- and postoperative MRI was also assessed. All 5 patients tolerated the procedure without any complications. Successful thermoablation was achieved in 4 of the 5 cases; the calcified SEGA was undertreated due to intratumor calcification, which prevented attainment of the target ablation temperature. The HHs underwent target tissue thermoablations that led to MR signal changes at the treatment site. For the patients harboring HHs, FUS thermoablations occurred without procedure-related complications and led to improvement in seizure control or hypothalamic hyperphagia. All 5 patients were discharged home on postoperative day 1 or 2, without any readmissions. There were no cases of hemorrhage, electrolyte derangement, endocrinopathy, or new neurological deficit in this cohort. This experience demonstrates that FUS thermoablation of centrally located brain lesions in adolescents and young adults can be performed safely and that it provides therapeutic benefit for associated symptoms.

Transient epileptic amnesia-A rare phenomenon in temporal lobe epilepsies

Transient epileptic amnesia (TEA) is arare phenomenon in temporal lobe epilepsy that is often unrecognized or misdiagnosed as transient global amnesia (TGA). It is postulated that TEA is due to both ictal and postictal disturbances. Response to antiseizure medication underlines its epileptic nature. In view of the increasing incidence of new-onset epilepsies in old age, an increase in TEA can be expected in the future. Analysis of TEA features in amonocentric case series. Asearch in our electronic patient data base yielded 10patients with TEA out of 7899patients over aperiod of 8years. Clinical and paraclinical features as well as findings of additional examinations were retrospectively collected. Data are given as mean ± SD. All 10patients were diagnosed with temporal lobe epilepsy. The mean age at manifestation of TEA was 59.1 ± 6.7years, the diagnosis was made with adelay of 21.9 ± 26.3months. The TEA lasted on average 56 ± 37 min, and 16 ± 9.9 TEA episodes per year were reported by the patients; out of the 10patients 6 reported that TEA usually occurred upon awakening. In 9of 10patients, there was evidence of typical seizure symptoms or other semiological elements during TEA. Interictal neuropsychological disturbances of temporal functions were seen in 8of 10patients and evidence of depressive disorder in 6of 10patients. Video EEG recordings revealed epileptiform activity during sleep in 4patients over the left and in 2patients over both temporal regions. In 3patients, magnetic resonance imaging displayed typical alterations of the temporomesial structures (in 2patients on the left and in 1the right side). Antiseizure medication improved seizure control in 7of 10patients (seizure freedom in 6patients), 3patients were lost to follow-up. TEA is rare, occurs in older adults and is correctly diagnosed after about 2years. Thorough assessment of additional symptoms and circumstances, the recurrent occurrence as well as typical EEG and imaging findings of temporal lobe epilepsy enables the distinction between TEA and TGA.

Perampanel as First Add-On Therapy in Patients with Focal-Onset Seizures in the FAME Trial: Post hoc Analyses of Efficacy and Safety Related to Maintenance Dose and Background Antiepileptic Drug Therapy.

Background and PurposeFAME (Fycompa® as first Add-on to Monotherapy in patients with Epilepsy; NCT02726074), a previously reported single-arm, phase IV study, showed that perampanel improved seizure control as first add-on to failed anti-seizure medication (ASM) monotherapy in 85 South Korean patients aged ≥12 years with focal-onset seizures (FOS) with/without focal to bilateral tonic-clonic seizures. We present results of three post hoc analyses of FAME that further assessed the efficacy and safety of perampanel.MethodsPatients were stratified by low- (4, 6 mg/day) versus high- (8, 10, 12 mg/day) dose maintenance perampanel, perampanel added to first- versus second-line ASM monotherapy, and concomitant background ASM monotherapy and perampanel dose. The primary endpoint was the proportion of patients with a ≥50% reduction in total seizure frequency during the 24-week maintenance period. Safety was assessed by the descriptive incidence of treatment-emergent adverse events (TEAEs).ResultsIn post hoc analyses, 50% responder rates were significantly higher for low- versus high-dose maintenance perampanel (88.6% vs. 40.0%; p<0.001) and when added to first- versus second-line ASM monotherapy (83.5% vs. 33.3%; p=0.013). By concomitant background ASM and perampanel maintenance dose, 50% responder rates were 100% for perampanel 4 mg/day added to carbamazepine, oxcarbazepine, lamotrigine, or valproic acid, and 85% when added to levetiracetam. Add-on perampanel improved 75% and seizure-free responder rates, and median percent changes from baseline seizure frequency per 28 days. Perampanel was well tolerated when added to ASM monotherapy, with dizziness being the most common TEAE.ConclusionsPost hoc analyses of FAME provide supportive data for the use of perampanel as an effective and well-tolerated first add-on treatment to a broad spectrum of ASM monotherapies in patients with FOS.

Biofeedback and Health Evidence-Based Biofeedback and Neurofeedback for People with Epilepsy and Seiz

Epilepsy is the fourth most common neurological disorder worldwide despite many anti-seizure medications. Biofeedback (BFB) and neurofeedback (NFB) have shown significant promise since the 1960s to improve seizure control, abnormalities in electroencephalography (EEG) and quantitative-EEG, and quality of life. Epilepsy is a disease of brain networks and BFB/NFB is a non-invasive, brain-centered, low-risk, low-cost, and reliable treatment for people with seizures/epilepsy and especially since standard seizure medications and epilepsy surgery often do not result in complete seizure control. Neuroscience healthcare clinician experience and a 60-year literature foundation show that BFB/NFB to improve brain dysregulation and abnormal network dynamics are known to be at the root of seizures/epilepsy. BFB/NFB trains individuals to self-regulate brain activity through real-time performance feedback. An exhaustive literature review for NFB/BFB and seizures/epilepsy (1960s–present) yielded 150 articles documenting improvements in seizures and EEG/QEEG abnormalities. Clinicians, insurers, and the public should support BFB/NFB as a first-line intervention for seizures/epilepsy.

LGG-38. Dose-dependent seizure control for an NF1 patient treated via MEK-inhibition for optic pathway glioma

BACKGROUND: Low-grade gliomas (LGG) are the most common solid tumor of childhood and can result in neurologic complications, including seizures, focal neurologic deficits, and learning difficulties. Molecularly targeted agents are increasingly being utilized to treat LGG, but the effect of these agents on accompanying neurologic complications are poorly understood. CASE: An 8-years old male with Neurofibromatosis Type 1 (NF1), medically refractory epilepsy and deep extensive glioma (extending from the optic pathway and involving the basal ganglia and corpus collosum) began selumetinib therapy due to radiographic and symptomatic tumor progression. Radiographic response (resolution of enhancement) was observed at 12 weeks of therapy, accompanied by improvement in seizure frequency, hemiparesis, and academic performance. Due to cardiotoxicity observed at that time (asymptomatic decreased ejection fraction and shortening fraction on echocardiogram), selumetinib was reduced to 50% dosing. On this reduced dose of selumetinib, seizures increased in frequency with subsequent worsening hemiparesis and recurrence of learning difficulties. One month later, dosing was escalated back to 100% due to interval resolution of cardiotoxicity, resulting in resolution of seizures and improvement in focal neurologic deficits and cognition. DISCUSSION: Dose-dependent response to MEK inhibition was observed without concurrent changes in anti-epileptic medications. The tumor was stable in size despite improved enhancement with treatment, suggesting that objective response by RANO criteria is not necessary for improved seizure control in LGG. Recent work has implicated the RAS/MEK/ERK pathway in neuronal precursor cells as a cause for epilepsy, suggesting that MEK inhibition of NF1-heterozygous neurons could be contributing to treatment response in this patient. Improvements in weakness and academic performance may have been due to improved seizure control or a direct effect of MEK inhibition on NF1-heterozygous neurons. CONCLUSION: MEK inhibition may have a clinically relevant anti-seizure effect for patients with pediatric LGG or NF1.

ID:16045 Simultaneous Deep Brain Stimulation and Responsive Neurostimulation for Drug Refractory Epilepsy: A Case Report Study

Nearly 25% of all epilepsy is Drug Resistant Epilepsy (DRE) 1-3. Surgical evaluation should be considered early in the course of the disease to minimize morbidity and the risk of sudden unexpected death in epilepsy (SUDEP)4-5. Neuromodulation is a viable option when resection or ablation is not feasible. A growing body of evidence shows improved seizure control and long-term efficacy with both7. With highly complex epileptogenic networks, a multimodality approach may provide an additional benefit to maximize seizure control. We report two cases of DRE who underwent anterior nucleus of the thalamus (ANT) DBS implantation followed by RNS implantation. To our knowledge, this is the first report of simultaneous DBS and RNS neurostimulation for the treatment of epilepsy.

Intelligence quotient (IQ) as a predictor of epilepsy surgery outcome

IntroductionAbout one-third of patients with epilepsy have a refractory form which is associated with important economic and psychosocial burden. Most of these patients also suffer from comorbidities. One of the most frequent is cognitive impairment. Resective surgery or neuromodulation techniques may improve seizure control. Several factors have been proposed as potential predictors of the success of surgery regarding seizure frequency. We aimed to study preoperative cognitive performance as a predictor of the epilepsy surgery outcome. MethodsIn this ambispective study we studied total intelligence quotients (IQ) measured before surgery with the Wechsler Adult Intelligence Scale (WAIS) as a potential predictor of Engel Class at 1 year after surgery. Then we included IQ in a multivariate model and tested its performance. ResultsPreoperative IQ was a significant and independent predictor of the Engel Class at 1 year after surgery (OR 0.94; CI 0.90–0.98; p = 0.007). The multivariate model including the age at epilepsy onset, education level, sex, and the type of surgery (resective versus palliative surgery) showed an area under the ROC curve of 0.85. ConclusionsA low intelligence level may constitute a marker of worse prognosis after epilepsy surgery. However, other predictors should also be considered when evaluating surgical candidates.

Cyclooxygenase-2 Inhibition as an Add-On Strategy in Drug Resistant Epilepsy-A Canine Translational Study.

Drug-resistant epilepsy is a common complaint in dogs and affects up to 30% of dogs with idiopathic epilepsy. Experimental data suggest that targeting cyclooxygenase-2 (COX-2) mediated signaling might limit excessive excitability and prevent ictogenesis. Moreover, the role of COX-2 signaling in the seizure-associated induction of P-glycoprotein has been described. Thus, targeting this pathway may improve seizure control based on disease-modifying effects as well as enhancement of brain access and efficacy of the co-administered antiseizure medication. The present open-label non-controlled pilot study investigated the efficacy and tolerability of a COX-2 inhibitor (firocoxib) add-on therapy in a translational natural occurring chronic epilepsy animal model (client-owned dogs with phenobarbital-resistant idiopathic epilepsy). The study cohort was characterized by frequent tonic–clonic seizures and cluster seizures despite adequate phenobarbital treatment. Enrolled dogs (n = 17) received a firocoxib add-on therapy for 6 months. Tonic–clonic seizure and cluster seizure frequencies were analyzed at baseline (6 months) months during the study (6 months). The responders were defined by a substantial reduction of tonic–clonic seizure and cluster seizure frequency (≥50%). In total, eleven dogs completed the study and were considered for the statistical analysis. Two dogs (18%, 2/11) were classified as responders based on their change in seizure frequency. Interestingly, those two dogs had the highest baseline seizure frequency. The overall tolerability was good. However, given the low percentage of responders, the present data do not support an overall considerable efficacy of COX-2 inhibitor add-on therapy to overcome naturally occurring phenobarbital-resistant epilepsy in dogs. Further translational evaluation should only be considered in the canine patients with a very high baseline seizure density.

Emerging Trends in Neuromodulation for Treatment of Drug-Resistant Epilepsy.

Epilepsy is a neurological disorder that affects more than 70 million people globally. A considerable proportion of epilepsy is resistant to anti-epileptic drugs (AED). For patients with drug-resistant epilepsy (DRE), who are not eligible for resective or ablative surgery, neuromodulation has been a palliative option. Since the approval of vagus nerve stimulation (VNS) in 1997, expansion to include other modalities, such as deep brain stimulation (DBS) and responsive neurostimulation (RNS), has led to improved seizure control in this population. In this article, we discuss the current updates and emerging trends on neuromodulation for epilepsy.

Extended resection for seizure control of pure motor strip focal cortical dysplasia during awake craniotomy: illustrative case.

BACKGROUNDFocal cortical dysplasias (FCD) represent highly intrinsically epileptogenic lesions that require complete resection for seizure control. Resection of pure motor strip FCD can be challenging. Effective control of postoperative seizures is crucial and extending the boundaries of resection in an eloquent zone remains controversial.OBSERVATIONSThe authors report a 52-year-old right-handed male with refractory epilepsy. The seizure phenotype was a focal crisis with preserved awareness and a clonic motor onset of right-hemibody. Epilepsy surgery protocol demonstrated a left pure motor strip FCD and a full-awake resective procedure with motor brain mapping was performed. Further resection of surgical boundaries monitoring function along intraoperative motor tasks with no direct electrical stimulation corroborated by intraoperative-neuromonitorization was completed as the final part of the surgery. In the follow-up period of 3-years, the patient has an Engel-IB seizure-control with mild distal lower limb palsy and no gate compromise.LESSONSThis report represents one of the few cases with pure motor strip FCD resection. In a scenario similar to this case, the authors consider that this variation can be useful to improve seizure control and the quality of life of these patients by extending the resection of a more extensive epileptogenic zone minimizing functional damage.

Responsive neurostimulation of the thalamus improves seizure control in idiopathic generalised epilepsy: initial case series

ObjectivesUp to 40% of patients with idiopathic generalised epilepsy (IGE) are drug resistant and potentially could benefit from intracranial neuromodulation of the seizure circuit. We present outcomes following 2 years...

Novel Loss of Function Variant in BCKDK Causes a Treatable Developmental and Epileptic Encephalopathy.

Branched-chain amino acids (BCAA) are essential amino acids playing crucial roles in protein synthesis and brain neurotransmission. Branched-chain ketoacid dehydrogenase (BCKDH), the flux-generating step of BCAA catabolism, is tightly regulated by reversible phosphorylation of its E1α-subunit. BCKDK is the kinase responsible for the phosphorylation-mediated inactivation of BCKDH. In three siblings with severe developmental delays, microcephaly, autism spectrum disorder and epileptic encephalopathy, we identified a new homozygous in-frame deletion (c.999_1001delCAC; p.Thr334del) of BCKDK. Plasma and cerebrospinal fluid concentrations of BCAA were markedly reduced. Hyperactivity of BCKDH and over-consumption of BCAA were demonstrated by functional tests in cells transfected with the mutant BCKDK. Treatment with pharmacological doses of BCAA allowed the restoring of BCAA concentrations and greatly improved seizure control. Behavioral and developmental skills of the patients improved to a lesser extent. Importantly, a retrospective review of the newborn screening results allowed the identification of a strong decrease in BCAA concentrations on dried blood spots, suggesting that BCKDK is a new treatable metabolic disorder probably amenable to newborn screening programs.

Safety and efficacy of cenobamate in patients with uncontrolled focal seizures - a review of the literature

Epilepsy is one of the most common diseases of the nervous system, characterized by the occurrence of recurrent and unprovoked seizures, which are an expression of abnormal brain activity associated with sudden and excessive bioelectric discharges. Partial seizures come from specific areas of the brain. They can run with motor, autonomic, sensory, and psychological symptoms. Currently, new active substances are sought that can be used in the treatment of drug-resistant partial seizures.&#x0D; The aim of the study is to evaluate the safety and efficacy of cenobamate in the treatment of patients with uncontrolled, partial seizures. Our study material consisted of publications, which were found in PubMed, Google Scholar, and Embase databases. In order to find the proper publications, the search has been conducted with the use of a combination of keywords like: “cenobamate”, “focal seizures”, “cenobamate in epilepsy”. The first step was to find proper publications from the last 10 years. The second step was to carry out an overview of the found publications.&#x0D; Studies have shown that treatment with cenobamate significantly improved seizure control in adults with uncontrolled focal seizures. Long-term use of cenobamate is safe and well-tolerated by patients. Most adverse events are mild or moderate.

Aura Type and Outcome After Anterior Temporal Lobectomy

Temporal lobe epilepsy (TLE) is one of the most common causes of medically refractory focal epilepsy. Anterior temporal lobectomy (ATL) leads to improved seizure control in patients with medically refractory TLE. Various auras are associated with TLE; however, the relationships between aura type and outcome after ATL are poorly understood. Our objective was to investigate the associations among clinical features, aura type, and seizure outcome after ATL. The records of patients who underwent ATL between 1993 and 2016 at a single institution (N= 174) were retrospectively reviewed. Demographic and clinical variables were compared among aura types using analysis of variance and logistic regression analysis. A multiple regression analysis was conducted to determine whether aura type predicted seizure outcome after ATL. Mesial temporal sclerosis (MTS) on magnetic resonance imaging inversely correlated with cephalic auras (P= 0.0090). Affective auras (P= 0.014) and somatosensory auras (P= 0.021) were correlated with findings of MTS on pathology, whereas this finding was inversely correlated with the presence of auditory auras (P= 0.0056). On multiple regression analysis, predictors of worse seizure outcome after ATL were cephalic auras (P= 0.0048), gustatory auras (P= 0.029), visual auras (P= 0.049), and tonic-clonic seizures (P= 0.047). Fewer preoperative antiepileptic medications (P= 0.0032), and presence of multiple auras (P= 0.011) were associated with better outcome. Cephalic auras, gustatory auras, and visual auras were associated with worse seizure outcome after ATL.

Comparison of care accessibility, costs, and quality with face-to-face and telehealth epilepsy clinic visits

During the COVID-19 pandemic, restrictions on reimbursement for telehealth visits were lifted and this visit type was suddenly available to patients around the United States of America. Telehealth visits offer potential cost savings for patients and families, which may vary by region of the world studied. Also, aggressiveness of the care patients receive may differ, and patients or families may be more likely to choose one visit type over another based on seizure control.This is a prospective face-to-face clinic versus telehealth clinic visit comparison study involving patients with seizures, their legal guardians, and caretakers who attend clinic. We compared travel distance, work-related factors, childcare, satisfaction of care, changes in seizure medication or diagnostics tests ordered, and willingness to cancel appointments to better understand the behavioral patterns of patients, caretakers, and providers.Our results indicate that many patients and families still prefer in-person interactions with their medical providers. Patient and family satisfaction levels were equal with both visit types. No significant difference was seen in medical management between face-to-face and telehealth visits. Also, prior seizure control did not dictate the type of visit chosen. Telehealth participants were significantly more willing to cancel appointments if asked to switch to face-to-face then face-to-face participants asked to complete telehealth visits. Surprisingly, we found that patients and families choosing telehealth were not statistically more likely to be employed or take less time off work. Also, distance from home to office was not significantly shorter for participants choosing face-to-face visits.Offering a combination of telehealth and face-to-face visits appears to be the optimal strategy in caring for patients with controlled and uncontrolled seizure disorders to ensure adherence with clinic visits and satisfaction with care. Our study suggests that providers are equally willing to adjust medications or order additional diagnostic testing regardless of visit type. Patients and families may be less likely to cancel telehealth visits than face-to-face visits; this finding may translate to improved seizure control and long-term decreased cost of care.

Beyond Resection: Neuromodulation and Minimally Invasive Epilepsy Surgery.

Epilepsy is a common neurological disease impacting both patients and healthcare systems. Approximately one third of patients have drug-resistant epilepsy (DRE) and are candidates for surgical options. However, only a small percentage undergo surgical treatment due to factors such as patient misconception/fear of surgery, healthcare disparities in epilepsy care, complex presurgical evaluation, primary care knowledge gap, and lack of systemic structures to allow effective coordination between referring physician and surgical epilepsy centers. Resective surgical treatments are superior to medication management for DRE patients in terms of seizure outcomes but may be less palatable to patients. There have been major advancements in minimally invasive surgeries (MIS) and neuromodulation techniques that may allay these concerns. Both epilepsy MIS and neuromodulation have shown promising seizure outcomes while minimizing complications. Minimally invasive methods include Laser Interstitial Thermal Therapy (LITT), RadioFrequency Ablation (RFA), Stereotactic RadioSurgery (SRS). Neuromodulation methods, which are more palliative, include Vagus Nerve Stimulation (VNS), Deep Brain Stimulation (DBS), and Responsive Neurostimulation System (RNS). This review will discuss the role of these techniques in varied epilepsy subtypes, their effectiveness in improving seizure control, and adverse outcomes.

Effects of Vagus Nerve Stimulation on Sleep-Disordered Breathing, Daytime Sleepiness, and Sleep Quality in Patients With Drug-Resistant Epilepsy.

Background and PurposeThis study aimed to determine the long-term effects of vagus nerve stimulation (VNS) on sleep-disordered breathing (SDB), daytime sleepiness, and sleep quality in patients with drug-resistant epilepsy (DRE). It also investigated the relationships among these main effects, clinical characteristics, and VNS parameters.MethodsTwenty-four patients were recruited. Paired t-tests and multiple linear regression analyses were performed to determine how the demographic and clinical characteristics of the patients influenced the variables that changed significantly after VNS treatment.ResultsAfter VNS, the patients showed significant increases in the apnea-hypopnea index (AHI), respiratory disturbance index (RDI), apnea index, hypopnea index, and oxygen desaturation index (ODI), as well as a significant decrease in the lowest arterial oxygen saturation (SaO2 nadir) (p<0.05). The multiple linear regression analyses demonstrated that the predictor of larger increases in AHI and RDI was being older at baseline, and that the predictor of a larger increase in apnea index was a longer epilepsy duration. The strongest predictor of a larger increase in ODI was a higher frequency of aura episodes at baseline, followed by a longer epilepsy duration. The strongest predictor of a larger decrease in SaO2 nadir was a higher frequency of aura episodes at baseline, followed by a longer epilepsy duration.ConclusionsThis study has confirmed that VNS improves seizure control in patients with DRE, whereas it increases obstructive sleep apnea (OSA). Furthermore, the increase in OSA is affected by age and the duration of epilepsy. Therefore, careful observation and monitoring of SDB is recommended in patients who undergo VNS.

Future of Neurology & Technology: Stereoelectroencephalography in Presurgical Epilepsy Evaluation.

Stereoelectroencephalography (SEEG) is not only a sophisticated and highly technological investigation but a new and better way to conceptualize the spatial and temporal dynamics of epileptic activity. The first intracranial investigations with SEEG were performed in France in the mid-twentieth century; however, its use in North America is much more recent. Given its significantly lower risk of complications and its ability to sample both superficial and deep structures and both hemispheres simultaneously, SEEG has become the preferred method to conduct intracranial EEG monitoring in most comprehensive epilepsy centers in North America. SEEG is an invasive neurophysiologic methodology used for advanced presurgical workup in the 20% of drug-resistant patients with more complex focal epilepsy in whom noninvasive investigations do not allow to decide on surgical candidacy. SEEG uses stereotactically implanted depth electrodes to map the origin and propagation of epileptic seizures by creating a 3-dimensional representation of the abnormal electrical activity in the brain. SEEG analysis takes into account the background, interictal, and ictal activity, as well as the results of cortical electrical stimulation procedures, to reliably delineate the epileptogenic network. By means of a clinical vignette, this article will walk general neurologists, but especially neurology trainees through the immense potential of this methodology. In summary, SEEG enables to accurately identify the epileptogenic zone in patients with drug-resistant focal epilepsy who otherwise would be not amenable to surgical treatment. In this patient population, SEEG is the best way to improve seizure control and achieve seizure freedom.