Trends of Neurosurgical Publications in High-Impact Medical Journals: A Bibliometric Study.

BACKGROUND: The subspecialized, clinically complex nature of neurosurgery should not result in marginalization or under-representation of neurosurgical scientific output. This study aims to provide an overview of the trends of neurosurgical publications in high-impact medical journals during the past 3 decades. METHODS: An electronic database search was performed to identify all articles affiliated with neurosurgery departments published in 10 highly regarded medical journals. The trend of the proportion of neurosurgical publications to total publications in these journals was examined over time. Subgroup analyses on the basis of location, setting, domain, grant source, and topic of the articles were performed. RESULTS: Overall, 2090 neurosurgical publications were identified in the selected journals, comprising 0.26% of those journals' publications. The proportion of neurosurgical publications to total publications in these journals increased over time, from 0.03% before 1991 to 0.35% after 2020. Most studies were single-center (82.7%), clinical (52.4%), and primary research (89%). The United States (40.1%), China (12.4%) and the United Kingdom (7.1%) had the greatest number of neurosurgical publications among those analyzed. The share of clinical neurosurgical articles increased over time compared with basic and translational articles (P = 0.01). Among neurosurgical subspecialties, neuro-oncology (60.1%), vascular (19.0%), and general (7.0%) had the greatest number of publications identified, with substantial increases in vascular publications over time. The mean number of citations per year received by neurosurgical articles has increased over time, from 1.65 (before 1991) to 4.12 (2010-2020). CONCLUSIONS: Neurosurgery's proportion of high-impact journal publications has increased over time.

What is the cognitive footprint of insular glioma?

Cognitive impairment has a profound deleterious impact on long-term outcomes of glioma surgery. The human insula, a deep cortical structure covered by the operculum, plays a role in a wide range of cognitive functions including interceptive thoughts and salience processing. Both low-grade (LGG) and high-grade gliomas (HGG) involve the insula, representing up to 25% of LGG and 10% of HGG. Surgical series from the past 30 years support the role of primary cytoreductive surgery for insular glioma patients; however, reported cognitive outcomes are often limited to speech and language function. The breath of recent neuroscience literature demonstrates that the insula plays a broader role in cognition including interoceptive thoughts and salience processing. This article summarizes the vast functional role of the healthy human insula highlighting how this knowledge can be leveraged to improve the care of patients with insular gliomas.

Complications of Implanted Vagus Nerve Stimulation: A Systematic Review and Meta-analysis.

INTRODUCTION: Vagus Nerve Stimulation (VNS) has emerged as a promising tool in ischemic stroke rehabilitation. However, there has been no systematic review summarizing its adverse effects, critical information for patients and providers when obtaining informed consent for this novel treatment. This systematic review and meta-analysis reports the adverse effects of VNS. METHODS: A systematic review was performed in accordance with PRISMA guidelines to identify common complications after VNS therapy. The search was executed in: Cochrane Central Register of Controlled Trials, Embase, and Ovid MEDLINE. All prospective, randomized controlled trials using implanted VNS therapy in adult patients were eligible for inclusion. Case studies and studies lacking complete complication reports were excluded. Extracted data included technology name, location of implantation, follow-up duration, purpose of VNS, and adverse event rates. RESULTS: After title-and-abstract screening of 4933 studies, 21 were selected for final inclusion. Across these studies, 1474 patients received VNS implantation. VNS was used as a potential therapy for epilepsy (9), depression (8), anxiety (1), ischemic stroke (1), chronic heart failure (1), and fibromyalgia (1). The 5 most common post-implant adverse events were voice alteration/hoarseness (n=671, 45.5%), paresthesia (n = 233, 15.8%), cough (n = 221, 15.0%), dyspnea (n = 211, 14.3%), and pain (n = 170, 11.5%). CONCLUSIONS: Complications from VNS are mild and transient, with reduction in severity and number of adverse events with increasing follow-up time. In prior studies, VNS has served as treatment option in several instances of treatment-resistant conditions, such as epilepsy and psychiatric conditions, and its use in stroke recovery and rehabilitation should continue to be explored.

Predicting 30-Day Non-Seizure Outcomes Following Temporal Lobectomy with Personalized Machine Learning Models.

BACKGROUND: Temporal lobe epilepsy is the most common reason behind drug-resistant seizures and temporal lobectomy (TL) is performed after all other efforts have been taken for a Temporal lobe epilepsy. Our study aims to develop multiple machine learning (ML) models capable of predicting postoperative outcomes following TL surgery. METHODS: Data from the American College of Surgeons National Surgical Quality Improvement Program database identified patients who underwent TL surgery. We focused on 3 outcomes: prolonged length of stay (LOS), nonhome discharges, and 30-day readmissions. Six ML algorithms, TabPFN, XGBoost, LightGBM, Support Vector Machine, Random Forest, and Logistic Regression, coupled with the Optuna optimization library for hyperparameter tuning, were tested. Models with the highest area under the receiver operating characteristic (AUROC) values were included in the web application. SHapley Additive exPlanations was used to evaluate importance of predictor variables. RESULTS: Our analysis included 423 patients. Of these patients, 111 (26.2%) experienced prolonged LOS, 33 (7.8%) had nonhome discharges, and 29 (6.9%) encountered 30-day readmissions. The top-performing models for each outcome were those built with the Random Forest algorithm. The Random Forest models yielded AUROCs of 0.868, 0.804, and 0.742 in predicting prolonged LOS, nonhome discharges, and 30-day readmissions, respectively. CONCLUSIONS: Our study uses ML to forecast adverse postoperative outcomes following TL. We developed accessible predictive models that enhance prognosis prediction for TL surgery. Making ML models available for this purpose represents a significant advancement in shifting toward a more patient-centric, data-driven paradigm.

Responsive Neurostimulation for People With Drug-Resistant Epilepsy and Autism Spectrum Disorder.

PURPOSE: Individuals with autism spectrum disorder (ASD) have comorbid epilepsy at much higher rates than the general population, and about 30% will be refractory to medication. Patients with drug-resistant epilepsy (DRE) should be referred for surgical evaluation, yet many with ASD and DRE are not resective surgical candidates. The aim of this study was to examine the response of this population to the responsive neurostimulator (RNS) System. METHODS: This multicenter study evaluated patients with ASD and DRE who underwent RNS System placement. Patients were included if they had the RNS System placed for 1 year or more. Seizure reduction and behavioral outcomes were reported. Descriptive statistics were used for analysis. RESULTS: Nineteen patients with ASD and DRE had the RNS System placed at 5 centers. Patients were between the ages of 11 and 29 (median 20) years. Fourteen patients were male, whereas five were female. The device was implanted from 1 to 5 years. Sixty-three percent of all patients experienced a >50% seizure reduction, with 21% of those patients being classified as super responders (seizure reduction >90%). For the super responders, two of the four patients had the device implanted for >2 years. The response rate was 70% for those in whom the device was implanted for >2 years. Improvements in behaviors as measured by the Clinical Global Impression Scale-Improvement scale were noted in 79%. No complications from the surgery were reported. CONCLUSIONS: Based on the authors' experience in this small cohort of patients, the RNS System seems to be a promising surgical option in people with ASD-DRE.

Long-term outcomes after responsive neurostimulation for treatment of refractory epilepsy: a single-center experience of 100 cases.

OBJECTIVE: Despite antiepileptic drugs, more than 30% of people with epilepsy continue to have seizures. Patients with such drug-resistant epilepsy (DRE) may undergo invasive treatment such as resection, laser ablation of the epileptogenic focus, or vagus nerve stimulation, but many are not candidates for epilepsy surgery or fail to respond to such interventions. Responsive neurostimulation (RNS) provides a neuromodulatory option. In this study, the authors present a single-center experience with the use of RNS over the last 5 years to provide long-term control of seizures in patients with DRE with at least 1 year of follow-up. METHODS: The authors performed a retrospective analysis of a prospectively collected single-center database of consecutive DRE patients who underwent RNS system implantation from September 2015 to December 2020. Patients were followed-up postoperatively to evaluate seizure freedom and complications. RESULTS: One hundred patients underwent RNS placement. Seven patients developed infections: 2 responded to intravenous antibiotic therapy, 3 required partial removal and salvaging of the system, and 2 required complete removal of the RNS device. No postoperative tract hemorrhages, strokes, device migrations, or malfunctions were documented in this cohort. The average follow-up period was 26.3 months (range 1-5.2 years). In terms of seizure reduction, 8 patients had 0%-24% improvement, 14 had 25%-49% improvement, 29 experienced 50%-74% improvement, 30 had 75%-99% improvement, and 19 achieved seizure freedom. RNS showed significantly better outcomes over time: patients with more than 3 years of RNS therapy had 1.8 higher odds of achieving 75% or more seizure reduction (95% CI 1.07-3.09, p = 0.02). Also, patients who had undergone resective or ablative surgery prior to RNS implantation had 8.25 higher odds of experiencing 50% or more seizure reduction (95% CI 1.05-65.1, p = 0.04). CONCLUSIONS: Responsive neurostimulator implantation achieved 50% or more seizure reduction in approximately 80% of patients. Even in patients who did not achieve seizure freedom, significant improvement in seizure duration, severity, or postictal state was reported in more than 68% of cases. Infection (7%) was the most common complication. Patients with prior resective or ablative procedures and those who had been treated with RNS for more than 3 years achieved better outcomes.

A multicenter retrospective study of patients treated in the thalamus with responsive neurostimulation.

Introduction: For drug resistant epilepsy patients who are either not candidates for resective surgery or have already failed resective surgery, neuromodulation is a promising option. Neuromodulatory approaches include responsive neurostimulation (RNS), deep brain stimulation (DBS), and vagal nerve stimulation (VNS). Thalamocortical circuits are involved in both generalized and focal onset seizures. This paper explores the use of RNS in the centromedian nucleus of the thalamus (CMN) and in the anterior thalamic nucleus (ANT) of patients with drug resistant epilepsy. Methods: This is a retrospective multicenter study from seven different epilepsy centers in the United States. Patients that had unilateral or bilateral thalamic RNS leads implanted in the CMN or ANT for at least 6 months were included. Primary objectives were to describe the implant location and determine changes in the frequency of disabling seizures at 6 months, 1 year, 2 years, and > 2 years. Secondary objectives included documenting seizure free periods, anti-seizure medication regimen changes, stimulation side effects, and serious adverse events. In addition, the global clinical impression scale was completed. Results: Twelve patients had at least one lead placed in the CMN, and 13 had at least one lead placed in the ANT. The median baseline seizure frequency was 15 per month. Overall, the median seizure reduction was 33% at 6 months, 55% at 1 year, 65% at 2 years, and 74% at >2 years. Seizure free intervals of at least 3 months occurred in nine patients. Most patients (60%, 15/25) did not have a change in anti-seizure medications post RNS placement. Two serious adverse events were recorded, one related to RNS implantation. Lastly, overall functioning seemed to improve with 88% showing improvement on the global clinical impression scale. Discussion: Meaningful seizure reduction was observed in patients who suffer from drug resistant epilepsy with unilateral or bilateral RNS in either the ANT or CMN of the thalamus. Most patients remained on their pre-operative anti-seizure medication regimen. The device was well tolerated with few side effects. There were rare serious adverse events. Most patients showed an improvement in global clinical impression scores.

Responsive Neurostimulation of the Thalamus for the Treatment of Refractory Epilepsy.

Introduction: One-third of patients with epilepsy continue to have seizures despite antiepileptic medications. Some of these refractory patients may not be candidates for surgical resection primarily because the seizure onset zones (SOZs) involve both hemispheres or are located in eloquent areas. The NeuroPace Responsive Neurostimulation System (RNS) is a closed-loop device that uses programmable detection and stimulation to tailor therapy to a patient's individual neurophysiology. Here, we present our single-center experience with the use of RNS in thalamic nuclei to provide long-term seizure control in patients with refractory epilepsy. Methods: We performed a prospective single-center study of consecutive refractory epilepsy patients who underwent RNS system implantation in the anterior (ANT) and centromedian (CM) thalamic nuclei from September 2015 to December 2020. Patients were followed postoperatively to evaluate seizure freedom and complications. Results: Twenty-three patients underwent placement of 36 RNS thalamic leads (CM = 27 leads, ANT = 9 leads). Mean age at implant was 18.8 ± 11.2 years (range 7.8-62 years-old). Two patients (8.7%) developed infections: 1 improved with antibiotic treatments alone, and 1 required removal with eventual replacement of the system to recover the therapeutic benefit. Mean time from RNS implantation to last follow-up was 22.3 months. Based on overall reduction of seizure frequency, 2 patients (8.7%) had no- to <25% improvement, 6 patients (26.1%) had 25-49% improvement, 14 patients (60.9%) had 50-99% improvement, and 1 patient (4.3%) became seizure-free. All patients reported significant improvement in seizure duration and severity, and 17 patients (74%) reported improved post-ictal state. There was a trend for subjects with SOZs located in the temporal lobe to achieve better outcomes after thalamic RNS compared to those with extratemporal SOZs. Of note, seizure etiology was syndromic in 12 cases (52.2%), and 7 patients (30.4%) had undergone resection/disconnection surgery prior to thalamic RNS therapy. Conclusion: Thalamic RNS achieved ≥50% seizure control in ~65% of patients. Infections were the most common complication. This therapeutic modality may be particularly useful for patients affected by aggressive epilepsy syndromes since a young age, those whose seizure foci are located in the mesial temporal lobe, and those who have failed prior surgical interventions.

Enhancing Safety in Epilepsy Surgery (EASINESS): Study Protocol for a Retrospective, Multicenter, Open Registry.

Introduction: Optimizing patient safety and quality improvement is increasingly important in surgery. Benchmarks and clinical quality registries are being developed to assess the best achievable results for several surgical procedures and reduce unwarranted variation between different centers. However, there is no clinical database from international centers for establishing standardized reference values of patients undergoing surgery for mesial temporal lobe epilepsy. Design: The Enhancing Safety in Epilepsy Surgery (EASINESS) study is a retrospectively conducted, multicenter, open registry. All patients undergoing mesial temporal lobe epilepsy surgery in participating centers between January 2015 and December 2019 are included in this study. The patient characteristics, preoperative diagnostic tools, surgical data, postoperative complications, and long-term seizure outcomes are recorded. Outcomes: The collected data will be used for establishing standardized reference values ("benchmarks") for this type of surgical procedure. The primary endpoints include seizure outcomes according to the International League Against Epilepsy (ILAE) classification and defined postoperative complications. Discussion: The EASINESS will define robust and standardized outcome references after amygdalohippocampectomy for temporal lobe epilepsy. After the successful definition of benchmarks from an international cohort of renowned centers, these data will serve as reference values for the evaluation of novel surgical techniques and comparisons among centers for future clinical trials. Clinical trial registration: This study is indexed at clinicaltrials.gov (NT 04952298).

Utility of 7 tesla MRI brain in 16 "MRI Negative" epilepsy patients and their surgical outcomes.

The objective is to quantitatively assess surgical outcomes in epilepsy patients who underwent scanning at 7T MRI whose lesions were undetectable at conventional field strengths (1.5T/3T). 16 patients who underwent an initial 1.5T/3T scan that was marked as non-lesional by a neuroradiologist and were candidates for epilepsy surgery were scanned at 7T. The 7T findings were evaluated by an expert neuroradiologist blinded to the suspected seizure onset zone (sSOZ). The relation of the neuroradiologist's findings compared with the sSOZ was classified as non-definite (no 7T lesion or lesion of no epileptogenic significance, or lesion of epileptogenic potential which localizes to the patient's sSOZ but is not the definitive cause), or definite (7T lesion of epileptogenic potential that highly localizes to the sSOZ and is confirmed through surgical intervention).. Each patient underwent neurosurgical intervention and postoperative Engel outcomes were obtained through retrospective chart review by an epileptologist. Of the 16 patients, 7 had imaging findings of definite epileptogenic potential at 7T while 9 had non-definite imaging findings. 15 out of 16 patients had Engel I, II, or III outcomes indicating worthwhile improvement. Patients with definite lesion status achieved Engel I surgical outcomes at higher rates (57.1%) than patients with non-definite lesion status (33.3%). Patients with normal clinical diagnostic scans at lower field strengths who have definite radiological findings on 7T corresponding to the sSOZ may experience worthwhile improvement from surgical intervention.

Readmission after neurosurgical intervention in epilepsy: A nationwide cohort analysis.

OBJECTIVE: Hospital readmissions result in increased health care costs and are associated with worse outcomes after neurosurgical intervention. Understanding factors associated with readmissions will inform future studies aimed at improving quality of care in those with epilepsy. METHODS: Patients of all ages with epilepsy who underwent a neurosurgical intervention were identified in the 2014 Nationwide Readmissions Database, a nationally representative dataset containing data from roughly 17 million US hospital discharges. Diagnosis of epilepsy was based on International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM)-based case definitions. Neurosurgical interventions for epilepsy: resective/disconnective surgery, responsive neurostimulation/deep brain stimulation, vagus nerve stimulation, radiosurgery, and intracranial electroencephalography were identified using ICD-9-CM procedure codes. Primary outcome was all-cause 30-day readmission following discharge from the index hospitalization. RESULTS: There were a total of 2284 index surgical admissions. Overall, 10.83% (n = 251) of patients following an index epilepsy surgery admission were readmitted within 30 days. Factors independently associated with 30-day readmission for all epilepsy surgery admissions were: Medicare insurance (P < .01), discharge disposition that was not home (P < .01), higher Elixhauser comorbidity indexes (P < .01), longer length of stay (P < .01), and adverse events of surgical and medical care during index stay (P = .04). In the multivariate model, Medicare insurance (hazard ratio [HR] 1.81 [1.29-2.53], P < .01) and length of stay (HR 1.02 [1.01-1.04], P < .01) remained significant independent predictors for 30-day readmission. The most common primary reason for readmissions was epilepsy/convulsions accounting for 22.85%. SIGNIFICANCE: Our results suggest that careful management of postoperative seizures and discharge planning after epilepsy surgery may be important to optimize outcomes and reduce the risk of readmission, particularly for patients on Medicare.

Approach Angle Affects Accuracy in Robotic Stereoelectroencephalography Lead Placement.

BACKGROUND: One third of patients with epilepsy fail to gain optimal control using antiepileptic drugs. New advances in epilepsy surgery have reshaped some diagnostic and therapeutic modalities into less invasive approaches. To understand the cortical epileptogenic networks, stereoelectroencephalography uses depth electrodes as a tool for invasive intracranial monitoring. These electrodes are now being placed using a robot instead of the traditional Talairach stereotactic grid and frame with comparable accuracy and the advantage of shortened surgical time. Whereas accuracy is important for correct cortical sampling and surgical morbidity, the factors that play a role in the deviation of the electrode's trajectory are not yet understood. The aim of this study was to determine if the angle the planned trajectory makes with the skull impacts the final accuracy of placement. METHODS: Twenty-five patients with 319 stereotactic trajectories were examined. Skew angle and accuracy measurements were computed based on preoperative and postoperative computed tomography scans fused with trajectories planned using ROSA robot software. RESULTS: Trajectories with a planned angle of >30° (oblique group) had significantly higher radial error (2.05 mm vs. 1.45 mm, P < 0.001) than trajectories with planned angles <30° (orthogonal group). CONCLUSIONS: The ROSA robotic system is a powerful tool that increases the speed and efficiency of stereotactic neurosurgery. Care should be taken when planning trajectories to avoid high skew angles. If a high skew angle is unavoidable, care should be taken to ensure a larger margin of safety.

Identification and Treatment of Drug-Resistant Epilepsy.

PURPOSE OF REVIEW: Drug-resistant epilepsy is a potentially life-threatening condition affecting one-third of people living with epilepsy. Despite existing evidence of improved outcomes in patients who received surgical treatment compared to continued medical treatment, epilepsy surgery remains underused in patients with drug-resistant epilepsy. This article discusses the gap between evidence and practice and common misconceptions about epilepsy surgery and reviews the current diagnostic and therapeutic surgical options. RECENT FINDINGS: Three randomized controlled trials comparing the medical versus surgical treatment for patients with drug-resistant epilepsy have shown the superiority of surgery in controlling seizures and improving patients' quality of life. In addition to resective surgery, neuromodulation through devices such as responsive neurostimulation and vagal nerve stimulation have also shown efficacy in seizure control that increases over time. Diagnostic and therapeutic surgical tools are tailored to the needs of each patient. SUMMARY: Appropriate patients with drug-resistant epilepsy benefit more from epilepsy surgery than from continuing medical treatment. These patients should be referred to comprehensive epilepsy centers where a thorough presurgical workup and surgical options can be provided. The gap between evidence and practice can be bridged by education, community outreach, and providers' earnest efforts to improve the quality of life of patients with epilepsy.

Quantitative Signal Characteristics of Electrocorticography and Stereoelectroencephalography: The Effect of Contact Depth.

PURPOSE: Patients undergoing epilepsy surgery often require invasive EEG, but few studies have examined the signal characteristics of contacts on the surface of the brain (electrocorticography, ECOG) versus depth contacts, used in stereoelectroencephalography (SEEG). As SEEG and ECOG have significant differences in complication rates, it is important to determine whether both modalities produce similar signals for analysis, to ultimately guide management of medically intractable epilepsy. METHODS: Twenty-seven patients who underwent SEEG (19), ECOG (6), or both (2) were analyzed for quantitative measures of activity including spectral power and phase-amplitude coupling during approximately 1 hour of wakefulness. The position of the contacts was calculated by coregistering the postoperative computed tomography with a reconstructed preoperative MRI. Using two types of referencing schemes-local versus common average reference-the brain regions where any quantitative measure differed systematically with contact depth were established. RESULTS: Using even the most permissive statistical criterion, few quantitative measures were significantly correlated with contact depth in either ECOG or SEEG contacts. The factors that predicted changes in spectral power and phase-amplitude coupling with contact depth were failing to baseline correct spectral power measures, use of a local rather than common average reference, using baseline correction for phase-amplitude coupling measures, and proximity of other grey matter structures near the region where the contact was located. CONCLUSIONS: The signals recorded by ECOG and SEEG have very similar spectral power and phase-amplitude coupling, suggesting that both modalities are comparable from an electrodiagnostic standpoint in delineation of the epileptogenic network.

Robotic surgical rehearsal on patient-specific 3D-printed skull models for stereoelectroencephalography (SEEG).

PURPOSE: Medically refractory epilepsy patients commonly require surgical alternatives for diagnosis and treatment. Stereoelectroencephalography (SEEG) is a useful diagnostic procedure in seizure focus elucidation. Modern techniques involve the use of robotics and neuronavigation for SEEG. A steep learning curve combined with multiple complex technologies employed during the case makes this procedure a perfect candidate for surgical rehearsal. This paper tests the feasibility of the use of patient-specific 3D-printed model for surgical rehearsal of robotic SEEG. METHODS: A 3D-printed model was created using the patient's cranial computed tomography and computed tomography angiography radiological imaging. A rehearsal in an operating room (OR) prior to the actual procedure date was used for surgical planning of SEEG electrodes, education of the residents and fellows as well as training of the support staff. Attention was paid to assure precise recreation of the surgical procedure. RESULTS: The patient-specific 3D-printed model tolerated each step of the procedure from facial registration, to drilling, bolt insertion and lead placement. Accuracy of the designed trajectory to the electrode final position was visually confirmed at the end of procedure. Important modification to the plan of eventual surgery improved the efficiency of the real operation. CONCLUSION: For surgical planning, education and training purposes in robotic SEEG, 3D-printed models may be utilized as a realistic anatomy tool. Potential applications of this technique include trajectory feasibility evaluation, patient positioning optimization, increasing OR efficiency, as well as neurosurgical education and patient counseling.

Intracarotid amobarbital disrupts synchronous and nested oscillatory activity ipsilateral to injection.

The mechanism of amobarbital action during the intracarotid amobarbital procedure is poorly understood. We report a patient case who underwent IAP while implanted with bilateral stereo-EEG. We analyzed the spectral power, phase amplitude coupling, and cluster-phase group synchrony during the procedure. Delta and gamma power increased bilaterally. By contrast, phase amplitude coupling increased only ipsilateral to the injection. Similarly, 4-30 Hz cluster-phase group synchrony declines and gamma cluster-phase group synchrony increases only ipsilateral to the injection. These results suggest that a possible additional mechanism for amobarbital action in the IAP is by altering the precise timing of oscillatory activity.

Language mapping using electrocorticography versus stereoelectroencephalography: A case series.

Direct electrical stimulation (DES) is sometimes used in epilepsy surgery to identify areas that may result in language deficits if resected. Extraoperative language mapping is usually performed using electrocorticography (ECOG) - grids and strip electrodes; however, given the better safety profile of stereoelectroencephalogaphy (SEEG), it would be desirable to determine if mapping using SEEG is also effective. We report a case series of fifteen patients that underwent language mapping with either ECOG (5), SEEG (9), or both (1). Six patients in the SEEG group underwent resection or ablation with only mapping via SEEG. No patients in the SEEG group that underwent resective or ablative surgery experienced persistent language deficits. These results suggest that language mapping with SEEG may be considered as a clinically useful alternative to language mapping with ECOG.

Simultaneous Treatment of Epilepsy and Secondary Dystonia After Anterior Temporal Lobectomy and Amygdalohippocampectomy.

BACKGROUND: The relationship between temporal lobe epilepsy and focal limb dystonia is a well-recognized phenomenon, yet its pathogenesis and anatomic foundation are not well understood. Here, we describe 2 patients with refractory focal epilepsy and contralateral focal limb dystonia whose seizures and dystonic symptoms simultaneously resolved after anterior temporal lobectomy and amygdalohippocampectomy. CASE DESCRIPTION: We identified 2 patients within the Mount Sinai Health system with improvement in dystonia after medial temporal lobectomy. Retrospective chart reviews for the clinical history were performed. Patient 1 suffered a traumatic injury of the right temporal lobe, developing left hemidystonia and epilepsy. He received a right amygdala-hippocampectomy, which resolved both. Patient 2 has a history of right temporal glioma resection complicated by an infarct, resulting in left hemidystonia and epilepsy. He received a right medial temporal resection, which nearly resolved both. CONCLUSION: Our cases demonstrate a medial temporal-basal ganglia network dysfunction in dystonia-epilepsy that was modulated and cured by resective surgery. We hypothesize that the mechanisms behind these observed phenomena were due to a pathologic connectivity of the basal ganglia and amygdala-hippocampus. To our knowledge, these are the first reported cases of dystonia and concomitant epilepsy resolving with temporal lobectomy and provide valuable prognostic information for similarly affected patients.

Epilepsy and Neuromodulation-Randomized Controlled Trials.

Neuromodulation is a treatment strategy that is increasingly being utilized in those suffering from drug-resistant epilepsy who are not appropriate for resective surgery. The number of double-blinded RCTs demonstrating the efficacy of neurostimulation in persons with epilepsy is increasing. Although reductions in seizure frequency is common in these trials, obtaining seizure freedom is rare. Invasive neuromodulation procedures (DBS, VNS, and RNS) have been approved as therapeutic measures. However, further investigations are necessary to delineate effective targeting, minimize side effects that are related to chronic implantation and to improve the cost effectiveness of these devices. The RCTs of non-invasive modes of neuromodulation whilst showing much promise (tDCS, eTNS, rTMS), require larger powered studies as well as studies that focus at better targeting techniques. We provide a review of double-blinded randomized clinical trials that have been conducted for neuromodulation in epilepsy.

Treatment of medically refractory seizures with responsive neurostimulation: 2 pediatric cases.

The responsive neurostimulation (RNS) system, an adjunctive treatment for pharmacoresistant partial-onset seizures with 1 or 2 foci, has been available to patients aged 18 years or older since the device's FDA approval in 2013. Herein, the authors describe their off-label application of this technology in 2 pediatric patients and the consequent therapeutic benefit without surgical complications or treatment side effects. A 14-year-old nonambulatory, nonverbal male with severe developmental delay was considered for RNS therapy for medically and surgically refractory epilepsy with bilateral seizure onsets in the setting of a normal radiological examination and a known neuropathological diagnosis of type I cortical dysplasia. The RNS system was implanted with strip electrodes placed on the left lateral frontal and right lateral temporal neocortex. At 19 months' follow-up, cortical stimulation resulted in sustained reduction in both seizure frequency-3 seizures per day down from 15 to 30 per day-and seizure severity. The patient subsequently underwent a trial of corticothalamic stimulation with a right temporal cortical strip and a left thalamic depth electrode, which resulted in a further 50% reduction in seizure frequency. In a second case, a 9-year-old right-handed female with radiological evidence of a small watershed infarct on the left and medically refractory seizures was referred for presurgical evaluation. Invasive monitoring revealed an unresectable seizure focus in the eloquent cortex of the left posterior frontal and parietal lobes. The RNS device was implanted with cortical leads placed at the putative seizure focus. At 21 months after surgery, the patient had been seizure free for 4 months, following a 17-month period in which the seizure frequency had decreased from 12 per month to 2 per month, with associated functional and behavioral improvement. The authors' results suggest that RNS may be a palliative option for children with intractable seizures whose condition warrants off-label use of the surgical device. The improved therapeutic effect noted with time and sustained RNS treatment points to a possible neuromodulatory effect.