Bilateral Electrode Placement Research Articles

Clinical Applicability and Safety of Conventional Frame-Based Stereotactic Techniques for Stereoelectroencephalography.

Stereoelectroencephalography (SEEG) is increasingly being recognized as an important invasive modality for presurgical evaluation of epilepsy. This study focuses on the clinical and technical considerations of SEEG investigations when using conventional frame-based stereotaxy, drawing on institutional experience and a comprehensive review of relevant literature. This retrospective observational study encompassed the surgical implantation of 201 SEEG electrodes in 16 epilepsy patients using a frame-based stereotactic instrument at a single tertiary-level center. We provide detailed descriptions of the operative procedures and technical nuances for bilateral and multiple SEEG insertions, along with several illustrative cases. Additionally, we present a literature review on the technical aspects of the SEEG procedure, discussing its clinical implications and potential risks. Frame-based SEEG electrode placements were successfully performed through sagittal arc application, with the majority (81.2%) of cases being bilateral and involving up to 18 electrodes in a single operation. The median skin-to-skin operation time was 162 minutes (interquartile range [IQR], 145-200), with a median of 13 minutes (IQR, 12-15) per electrode placement for time efficiency. There were two occurrences (1.0%) of electrode misplacement and one instance (0.5%) of a postoperative complication, which manifested as a delayed intraparenchymal hemorrhage. Following SEEG investigation, 11 patients proceeded with surgical intervention, resulting in favorable seizure outcomes for nine (81.8%) and complete remission for eight cases (72.7%). Conventional frame-based stereotactic techniques remain a reliable and effective option for bilateral and multiple SEEG electrode placements. While SEEG is a suitable approach for selected patients who are strong candidates for epilepsy surgery, it is important to remain vigilant concerning the potential risks of electrode misplacement and hemorrhagic complications.

Breath-by-breath comparison of a novel percutaneous phrenic nerve stimulation approach with mechanical ventilation in juvenile pigs: a pilot study

About one in three critically ill patients requires mechanical ventilation (MV). Prolonged MV, however, results in diaphragmatic weakness, which itself is associated with delayed weaning and increased mortality. Inducing active diaphragmatic contraction via electrical phrenic nerve stimulation (PNS) not only provides the potential to reduce diaphragmatic muscular atrophy but also generates physiological-like ventilation and therefore offers a promising alternative to MV. Reasons why PNS is not yet used in critical care medicine are high procedural invasiveness, insufficient evidence, and lack of side-by-side comparison to MV. This study aims to establish a minimal-invasive percutaneous, bilateral electrode placement approach for sole PNS breathing and thereby enable, for the first time, a breath-by-breath comparison to MV. Six juvenile German Landrace pigs received general anesthesia and orotracheal intubation. Following the novel ultrasound-guided, landmark-based, 4-step approach, two echogenic needles per phrenic nerve were successfully placed. Stimulation effectiveness was evaluated measuring tidal volume, diaphragmatic thickening and tomographic electrical impedance in a breath-by-breath comparison to MV. Following sufficient bilateral phrenic nerve stimulation in all pigs, PNS breaths showed a 2.2-fold increase in diaphragmatic thickening. It induced tidal volumes in the lung-protective range by negative pressure inspiration and improved dorso-caudal regional ventilation in contrast to MV. Our study demonstrated the feasibility of a novel ultrasound-guided, percutaneous phrenic nerve stimulation approach, which generated sufficient tidal volumes and showed more resemblance to physiological breathing than MV in a breath-by-breath comparison.

Effects of electrode placement on symptoms, memory, and sustainment of results after electroconvulsive therapy- A comparative study

ABSTRACT Background: The memory-related side-effects rank among the strongest reasons for hostility against Modified Electroconvulsive Therapy (MECT). Most of the studies comparing the Unilateral v/s Bilateral Electrode placements on memory have been conducted on patients with depression while very few studies have been conducted on patients with psychosis in the Indian population. Aim: To compare the effects of right unilateral (RU/L) and bilateral (B/L) MECT on the severity of symptoms as well as memory in patients with psychosis after the fourth session and two weeks after the final session of the MECT. Materials and Methods: One hundred patients having a psychotic illness were randomized into either RU/L or B/L group. Comprehensive psychopathological rating scale (CPRS), clinical global impressions scale (CGI-S), and PGI-memory scale were applied before starting of MECT, after four sessions of MECT and two weeks after the last session of ECT. Results: The results show similar symptomatic improvement in patients receiving RU/L and B/L MECT and the results persisted beyond the therapy sessions. But, in the case of RU/L-MECT group, the deterioration in memory was less as compared to the B/L-MECT group. Both groups had no significant difference in psychopathology and its severity (CPRS and CGI). Both groups were significantly different in memory side effects after the fourth session and two weeks after the last session. Both groups showed a consistent downward trend in psychopathology and its severity. The consistent fall in the total PGI scores remained even after two weeks of the final session in the B/L group (total of six points as compared to baseline) while it came to baseline levels in the RU/L group. Both groups differed significantly in total PGI scores after the fourth session and two weeks after the final session. Conclusion: This study points toward a favorable outcome in the case of therapeutic response with MECT without any significant difference between both types of electrode placements and even after stopping MECT, the improvement appears to be stable over time. Although, there was a side-effect of memory impairment, it appears to be for a shorter duration and it improves with time. The side-effect profile of RU/L electrode placement is lower as compared to bilateral placement. In the post-MECT period, the patients receiving MECT with RU/L electrode placement showed better improvement in memory functions.

The Relative Effectiveness of Bilateral and Unilateral Electrode Placement in Electroconvulsive Therapy (ECT) in Patients With Major Depressive Disorder: A Retrospective Cohort Study.

Background This study is focused on the comparative efficacy of bilateral and unilateral electroconvulsive therapy (ECT) on depressive symptoms in patients at the Perth Clinic for the period from 2016 to 2021. Methods This was a retrospective cohort study of 485 patients who received ECT treatment. The expected improvements in depressive symptoms were evaluated by the Depression Anxiety Stress Scale(DASS)assessment tool filled out by the patients on admission and discharge from the hospital. Only the depression score of the DASS scale was utilised for this research. Results The results suggested that both electrode placements resulted in a significant improvement in depressive symptoms. The positive response rates for the bilateral and unilateral electrode placements were 78.3% and 71.6%, respectively. There was no difference between males and females in the average DASS score at discharge for bilateral and unilateral electrode placements. Conclusions This study confirmed that the results obtained at the Perth Clinic are similar to the existing international research results on the same topic. Bifrontal and unilateral ECT electrode placements are equally efficacious in improving depressive symptoms in patients suffering from major depressive disorder (MDD).

Missing Piece of Puzzle: Electro-Convulsive Therapy (ECT) in Patients with anti-NMDA Receptor Encephalitis (P5-5.012)

<h3>Objective:</h3> To emphasize the importance of early clinical recognition of catatonia and implementation of ECT as adjuvant therapy in patients with anti-NMDAR encephalitis. <h3>Background:</h3> Catatonia is a symptom of anti-NMDAR encephalitis which can evolve rapidly into malignant catatonia with autonomic instability and increased morbidity. Although early immunomodulatory therapy is important to treat the underlying autoimmune disorder, resistant catatonia may require adjuvant management with ECT. <h3>Design/Methods:</h3> Not applicable. <h3>Results:</h3> We describe the cases of three females aged 23.7 ± 2.5, who were diagnosed with anti-NMDAR encephalitis. They presented with neuropsychiatric symptoms and were promptly and empirically treated with IV solumedrol with oral prednisone taper, IVIG, +/− plasma exchange (case 3), preceding diagnostic confirmation via CSF NMDA antibody positivity. Ovarian teratomas were detected in all cases and resected shortly after hospitalization. Additionally, cases 1 and 2 received Rituximab while hospitalized, and cases 2 and 3 received anti-seizure medications for temporal onset seizures. In spite of this, all required escalating large doses of benzodiazepines, in conjunction with amantadine and bromocriptine, for refractory malignant catatonia with dysautonomia. ECT treatments were thus initiated (once to twice daily for first week, followed by three times weekly) with bilateral electrode placement. All cases tolerated ECT treatments well and were gradually noted to have marked clinical improvement as was measured by the Bush-Francis Catatonia Rating Scale (BFCRS) (initial assessment: 27.6 ± 8.3; last assessment 1.3 ± 1.5). <h3>Conclusions:</h3> This case series supports the growing body of evidence emphasizing the importance of clinical recognition of catatonia among patients with suspected or confirmed anti-NMDAR encephalitis, and the early implementation of ECT into treatment algorithms. The use of standardized assessment tools such as the BFCRS and cognitive impairment screening scales should be considered for monitoring of symptom response and tolerability. <b>Disclosure:</b> Dr. Wadi has nothing to disclose. Dr. Mandge has nothing to disclose.

Initial Clinical Experience with Thin-Film Polyimide Subdural Electrodes for Seizure Monitoring (P2-1.005)

<h3>Objective:</h3> NA <h3>Background:</h3> Subdural grid-and-strips are used routinely in pre-surgical evaluations for people with drug-resistant epilepsy (DRE). Thin-film polyimide electrodes (NeuroOne Evo, 0.08mm) which have been approved for clinical use, are thinner and better conform to brain convolutions than current market grids. <h3>Design/Methods:</h3> We present two patients with DRE who underwent intracranial EEG (iEEG) monitoring with thin-film polyimide subdural electrode grid- and-strip electrodes as well as traditional EEG for pre-surgical evaluation. Patient 1 had a prior left mesial temporal lobe ablation with seizure recurrence. They underwent left temporal craniotomy with implantation of two subdural grids, three strips and additional depth electrodes. IEEG demonstrated two habitual seizures arising from anterior temporal subdural strips. Functional mapping identified the basal-temporal and Wernicke’s speech areas. Left anterior temporal lobectomy was performed and he remains seizure free 9 months post-resection. Patient 2 underwent bilateral stereoEEG electrode placement with coverage in the frontal/temporal/insular regions and subdural strip electrodes. IEEG demonstrated seizure onset from the left hippocampus and right hippocampal spikes. Given bilateral findings, they underwent Responsive Neurostimulation System implantation. <h3>Results:</h3> The two patients underwent subdural electrode placements without complications. IEEG recordings were comparable between NeuroOne Evo and traditional electrodes in terms of integrity, artifactual content and signal recording characteristics. The thinner profile of the Evo grid tail facilitated dura closure and reduced mass effect compared to traditional grids. By trimming material from the tip of the subdural strip, the electrode was placed through a burr hole without difficulty. Recording from these grids contributed to presurgical evaluation and led to surgical interventions. <h3>Conclusions:</h3> Our initial experience suggests that thin-film electrodes are a viable option for subdural iEEG that could safely minimize intracranial mass effect/brain shift and improve surgical ease of use. <b>Disclosure:</b> Dr. Reina has nothing to disclose. Dr. Song has received personal compensation in the range of $0-$499 for serving as a Consultant for Clearpoint Neuro. The institution of Dr. Song has received research support from NIH. Dr. Culler has nothing to disclose. Dr. Aronson has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Medtronic.

Electroconvulsive therapy following incident bipolar disorder: When, how, and for whom?

The use of electroconvulsive therapy (ECT) in the treatment of bipolar disorder (BD) remains poorly described. Based on data from Danish registries with complete nationwide coverage, this study of patients with incident BD aimed to describe when, how, and for whom ECT is used in the context of BD. We identified patients receiving their first diagnosis of BD in the period from 2008 to 2018, who subsequently received ECT. Descriptive statistics were used to clarify when, how, and for whom ECT is used. We identified 1338 patients with incident BD who subsequently received ECT. The median age at the first ECT session was 50.6 years (interquartile range [IQR]: 26.4), and 62% of those treated with ECT were female. The median time from the diagnosis of BD to the first ECT treatment was 0.6 years (IQR: 2.6), and 58% of the patients receiving ECT had the first treatment within the first year after being diagnosed with BD. The most common indication for the first ECT treatment was depression (mainly non-psychotic depression), followed by mania (mainly psychotic mania). The first ECT session was typically provided to inpatients (97%), upon patient consent (98%) and with bilateral electrode placement (60%). A substantial proportion of the patients with incident BD who receive ECT require this treatment within the first year after the diagnosis. The most common indication for ECT is depression followed by (psychotic) mania. Inpatient voluntary ECT using bilateral electrode placement is the most common form of administration.

Effect of Modified Bifrontotemporal Electroconvulsive Therapy on Executive Function in Patients With Psychiatric Illness: A Longitudinal Observational Study.

The study was conducted to compare the pre-electroconvulsive therapy (ECT) and post-ECT status of the executive functions of patients and report any deficits found at long-term follow-up. The secondary objective of the study was to compare the performance at executive function tests after ECT with patient characteristics and ECT parameters. In a prospective longitudinal observational study, 50 patients in the age group of 18 to 65 years who were receiving modified bifrontotemporal ECT for the first time and admitted in psychiatry ward of a tertiary care hospital from July 2015 to June 2016 were assessed for executive functions using a neuropsychological battery consisting of digit span forward, digit span backward, spatial span forward, spatial span backward, phonemic verbal fluency test, semantic verbal fluency test, Stroop test, and Wisconsin Card Sorting Test, a day before ECT and then followed up at 3 and 6 months. Patients' score improved on all the tests of executive function at 3-month follow-up and was significant for some tests. Improvement was sustained for all the tests 6 months after ECT. Number of years of formal education of patients before illness significantly influenced patients' performance on most of the executive function tests after ECT. Younger age of the patient positively influenced patients' performance on digit span forward and backwards and semantic verbal fluency. There are no executive function deficits 3 to 6 months after brief pulse modified ECT with bilateral electrode placement. A higher premorbid education level is associated with better performance on executive functions after ECT.

Electric field strength induced by electroconvulsive therapy is associated with clinical outcome

The clinical effect of electroconvulsive therapy (ECT) is mediated by eliciting a generalized seizure, which is achieved by applying electrical current to the head via scalp electrodes. The anatomy of the head influences the distribution of current flow in each brain region. Here, we investigated whether individual differences in simulated local electrical field strength are associated with ECT efficacy. We modeled the electric field of 67 depressed patients receiving ECT. Patient’s T1 magnetic resonance images were segmented, conductivities were assigned to each tissue and the finite element method was used to solve for the electric field induced by the electrodes. We investigated the correlation between modelled electric field and ECT outcome using voxel-wise general linear models. The difference between bilateral (BL) and right unilateral (RUL) electrode placement was striking. Even within electrode configuration, there was substantial variability between patients. For the modeled BL placement, stronger electric field strengths appeared in the left hemisphere and part of the right temporal lobe. Importantly, a stronger electric field in the temporal lobes was associated with less optimal ECT response in patients treated with BL-ECT. No significant differences in electric field distributions were found between responders and non-responders to RUL-ECT. These results suggest that overstimulation of the temporal lobes during BL stimulation has negative consequences on treatment outcome. If replicated, individualized pre-ECT computer-modelled electric field distributions may inform the development of patient-specific ECT protocols.

Structural changes induced by electroconvulsive therapy are associated with clinical outcome

BackgroundElectroconvulsive therapy (ECT) is the most effective treatment option for major depressive disorder, so understanding whether its clinical effect relates to structural brain changes is vital for current and future antidepressant research. ObjectiveTo determine whether clinical response to ECT is related to structural volumetric changes in the brain as measured by structural magnetic resonance imaging (MRI) and, if so, which regions are related to this clinical effect. We also determine whether a similar model can be used to identify regions associated with electrode placement (unilateral versus bilateral ECT). MethodsLongitudinal MRI and clinical data (Hamilton Depression Rating Scale) was collected from 10 sites as part of the Global ECT-MRI research collaboration (GEMRIC). From 192 subjects, relative changes in 80 (sub)cortical areas were used as potential features for classifying treatment response. We used recursive feature elimination to extract relevant features, which were subsequently used to train a linear classifier. As a validation, the same was done for electrode placement. We report accuracy as well as the structural coefficients of regions included in the discriminative spatial patterns obtained. ResultsA pattern of structural changes in cortical midline, striatal and lateral prefrontal areas discriminates responders from non-responders (75% accuracy, p < 0.001) while left-sided mediotemporal changes discriminate unilateral from bilateral electrode placement (81% accuracy, p < 0.001). ConclusionsThe identification of a multivariate discriminative pattern shows that structural change is relevant for clinical response to ECT, but this pattern does not include mediotemporal regions that have been the focus of electroconvulsive therapy research so far.

Infections in Deep Brain Stimulator Surgery.

Introduction: Deep brain stimulation has emerged as an effective treatment for movement disorders such as Parkinson’s disease, dystonia, and essential tremor with estimates of >100,000 deep brain stimulators (DBSs) implanted worldwide since 1980s. Infections rates vary widely in the literature with rates as high as 25%. Traditional management of infection after deep brain stimulation is systemic antibiotic therapy with wound incision and debridement (I&D) and removal of implanted DBS hardware. The aim of this study is to evaluate the infections occurring after DBS placement and implantable generator (IPG) placement in order to better prevent and manage these infections.Materials/Methods: We conducted a retrospective review of 203 patients who underwent implantation of a DBS at a single institution. For initial electrode placement, patients underwent either unilateral or bilateral electrode placement with implantation of the IPG at the same surgery and IPG replacements occurred as necessary. For patients with unilateral electrodes, repeat surgery for placement of contralateral electrode was performed when desired. Preoperative preparation with ethyl alcohol occurred in all patients while use of intra-operative vancomycin powder was surgeon dependent. All patients received 24 hours of postoperative antibiotics. Primary endpoint was surgical wound infection or brain abscess located near the surgically implanted DBS leads. Infections were classified as early (<90 days) or late (>90 days). Infectious organisms were recorded based on intra-operative wound cultures. Number of lead implantations, IPG replacements and choice of presurgical, intra-operative, and postsurgical antibiotics were recorded and outcomes compared.Results: Two hundred and three patients underwent 391 electrode insertions and 244 IPG replacements. Fourteen patients developed an infection (10 early versus 4 late); 12 after implantation surgery (3%) and 2 after IPG replacement surgery (0.8%). No intracranial abscesses were found. Most common sites were the chest and connector. Staphylococcus aureus (MSSA) was the most common organism. Intra-operative vancomycin powder did not decrease infection risk. Vancomycin powder use was shown to increase risk of infection after electrode implantation surgery (Relative Risk 5.5080, p = 0.02063). Complete hardware removal occurred in eight patients, one patient had electrode only removal, three patients with I&D and no removal of hardware, and two patients with removal of IPG and extensor cables only. All patients were treated with postoperative intravenous antibiotics and no recurrent infections were found in patients with hardware left in place.Discussion/Conclusion: Infections after DBS implantation and IPG replacement occurred in 3% and 0.8% of patients respectively in our study which is lower than reported historically. Early infections were more common. No intracranial infections were found. Intra-operative use of vancomycin was not shown to decrease risk of infection after electrode implantation surgery or IPG replacement. However, in our study it was shown to increase risk of infection after electrode implantation surgery. Treatment includes antibiotic therapy and debridement with or without removal of hardware. DBS hardware can be safely left in place in select patients who may have significant adverse effects if it is removed.

Annual Meeting Attendees Debate ECT Best Practices

Annual Meeting Attendees Debate ECT Best Practices

Electroconvulsive Therapy Practice in the Kingdom of Denmark: A Nationwide Register- and Questionnaire-Based Study.

The aim of this study was to survey and describe the contemporary practice of electroconvulsive therapy (ECT) in the Kingdom of Denmark (Denmark, Greenland, and the Faroe Islands). Data regarding number of ECTs and number of patients with different diagnoses treated with ECT were retrieved from the Danish National Patient Registry. In addition, a 45-item questionnaire was sent to all psychiatric departments practicing ECT in Denmark (n = 26), Greenland (n = 1), and the Faroe Islands (n = 1). According to the Danish National Patient Registry, a total of 21,730 ECTs were administered to 1891 unique patients in 2017. All departments responded to the survey. The psychiatric departments' attitude toward ECT was generally favorable and in accord with official guidelines. Maintenance ECT was used in all departments but one. Bilateral electrode placement was preferred. All departments used a preselected age-based dosing strategy. Involuntary ECT was performed in 96% of the psychiatric departments, but infrequently (3% of all treatments). All departments used a Thymatron (brief pulse) device, and in 71% of the departments, ECT was given in a specialized ECT unit and preanesthetic evaluation was carried out in all departments. The departments reported several different practices regarding documentation and monitoring of treatment effect, patient consent, screening for side effects (including cognitive side effects), and guidelines for the discharge of ECT patients. Electroconvulsive therapy is frequently used in Denmark, Greenland, and the Faroe Islands in a relatively uniform way in adherence with clinical guidelines.

Minimally Invasive Bilateral Anterior Cingulotomy via Open Minicraniotomy Using a Novel Multiport Cisternoscope: A Cadaveric Demonstration.

Bilateral anterior cingulotomy has been used to treat chronic pain, obsessive compulsive disorder, and addictions. Lesioning of the target area is typically performed using bilateral stereotactic electrode placement and target ablation, which involves transparenchymal access through both hemispheres. To evaluate an endoscopic direct-vision lesioning using a unilateral parasagittal minicraniotomy for minimally invasive bilateral anterior cingulotomy using a novel multiport endoscope through the anterior interhemispheric fissure. A novel multiport magnetic resonance imaging (MRI)-compatible neuroendoscope prototype is used to demonstrate cadaveric cingulate lesioning through a lateral imaging port while simultaneously viewing the pericallosal arteries as landmarks through a tip imaging port. The lateral port enables extended lesioning of the gyrus while rotation of the endoscope about its axis provides access to homologous areas of both hemispheres. Cadaver testing confirmed the capability to navigate the multiport neuroendoscope between the hemispheres using concurrent imaging from the tip and lateral ports. The lateral port enabled exploration of the gyrus, visualization of lesioning, and subsequent inspection of lesions. Tip-port imaging provided navigational cues and allowed the operator to ensure that the endoscope tip did not contact tissue. The multiport design required instrument rotation in the coronal plane of only 20° to lesion both gyri, while a standard endoscope necessitated a rotation of 54°. Multiport MRI-compatible endoscopy can be effectively used in cisternal endoscopy, whereby a unilateral parasagittal minicraniotomy can be used for endoscopic interhemispheric bilateral anterior cingulotomy.

Stimulus intensity determined by dose-titration versus age-based methods in electroconvulsive therapy in Thai patients.

ObjectivesThis study aimed to compare the accuracy of the stimulus intensity (SI) calculated by age-based methods with that using the dose-titration method.MethodsThe initial seizure threshold (IST) was determined using a standardized dose titration in hospitalized Thai patients treated with right unilateral (RUL, n=32) and bilateral (BL, n=57) electrode placement. The correlation between the IST and clinical variables was analyzed. The estimated SI based on the patient’s age was compared with the SI determined by dose titration.ResultsAge was highly predictive of the IST for both groups (RUL, P=0.012; BL, P=0.045). Gender (P=0.006) and anticholinergic drug use (P=0.025) predicted the IST for the BL group. For the RUL group, the mean±SD (median) SI estimated using the half-age and age methods was 158±46 (169) mC and 315±92 (338) mC, respectively. The SI determined using the dose-titration method was higher compared with the half-age method and lower compared with the age method. For the RUL group, 31% of subjects using the half-age method and 22% of subjects using the age method would have received an SI within ±20% of that computed using dose titration. Additionally, 19% of subjects using the half-age method and 19% using the age method would have received unacceptably low (<50%) or high (>200%) intensities. For the BL group, 18% of subjects using the half-age method and 32% using the age method would have received an SI within ±20% of that computed using dose titration. Additionally, 39% with the half-age method and 18% with the age method would have received an unacceptably low or high SI, respectively.ConclusionAge strongly predicts the IST, but it does not robustly predict the SI compared with dose titration because the SI calculated using age-based methods results in an unacceptably low or high SI that is associated with a marked risk of adverse effects or inadequate response. We recommend the dose-titration method to determine the SI.

Determinants of relapse after electroconvulsive therapy in depressed patients

Maintaining remission after successful acute treatment remains a challenge in the use of electroconvulsive therapy (ECT). For this purpose, the concept of gradually tapered continuation ECT (C-ECT) has been increasingly propagated. The present study is aimed at identifying factors that contribute to relapse after ECT in depressed patients. After successful acute treatment of a depressive episode with ECT, all patients were offered a fixed schedule of C-ECT. The number of C-ECT sessions varied in this naturalistic setting depending on compliance. All patients with follow-up data of at least 6 months were included (n = 82). Survival analyses with time to relapse as dependent variable were used to estimate the risk of relapse. 34.1 % of the patients relapsed within 6 months. Factors associated with a decreased relapse rate were: 1. C-ECT treatment, especially within the first three month; 2. higher mean charge during I-ECT; 3. switch from unilateral to bilateral electrode placement during I-ECT, and 4. male sex. However, the sensitivity analyses suggest that the influence of sex on relapse was limited to the first three months of the continuation phase. As expected, C-ECT reduced relapse rates, especially when performed early after I-ECT. Besides, increased charge and a change of electrode placement from unilateral to bilateral during the index series were associated with a lower risk of relapse. Compared to men, there was a higher rate of relapse in women.

Time Trends and Variations in Electroconvulsive Treatment in Denmark 2008 to 2014: A Nationwide Register-Based Study.

The aim of this study was to determine status and variations in the practice of electroconvulsive treatment (ECT) in Denmark in patient characteristics, indications, treatment patterns, and hospital region. All 140,627 ECTs registered in the Danish National Patient Registry between 2008 and 2014 were retrieved together with information on patient characteristics. Annual treated person rates were calculated for sex, age, admission diagnosis, and region. The overall ECT treatment rate was 36 (95% confidence interval, 34-38) per 100,000 resident population during the study period. The rate was highest in women and increased with age. There were modest, however, stable regional differences in rates (extremal quotient = 1.4). Electroconvulsive treatment was most commonly used in patients with depression with (19.4%) or without (54.9%) psychotic symptoms. The median number of ECTs administered per patient was 10 and highest in patients with schizophrenia, schizoaffective, or bipolar disorders. A total of 51%, 14%, and 33% of ECTs were administered with bilateral, unilateral, and unspecified electrode placement, respectively. There were regional differences in electrode placement specification and use. Although some variation was seen across hospital regions and electrode placement, ECT in Denmark was provided with relative stability over time and indications compared with most other countries in Europe and North America.

A systematic review of left unilateral electroconvulsive therapy.

To systematically review the published clinical trials, case series, and case reports on left unilateral (LUL) electrode placement for clinical electroconvulsive therapy (ECT). PubMed, Ovid Medline, and the Cochrane Library were searched for articles concerning LUL ECT. Number of patients, efficacy, and cognitive outcomes were extracted from the papers that met our inclusion criteria. A total of 52 articles were included in this review, consisting of 33 clinical trials, seven case series, and 12 case reports. Overall, the efficacy of LUL electrode placement for the treatment of depression and psychosis is similar to that of right unilateral (RUL) and bilateral (BL) electrode placements. Patients receiving LUL ECT tend to experience more verbal memory impairment than patients receiving RUL ECT, but less verbal impairment than patients receiving BL ECT. In contrast, patients receiving LUL ECT tended to experience the least visual and nonverbal memory impairment, compared to patients receiving RUL or BL ECT.

Abstract TP145: Anodal 2mA Transcranial Direct Current Stimulation Over Affected Parietal-Insular-vestibular Cortex Shows No Effect on Lateropulsion Following Strokei

Objective: To assess the effects of 2mA transcranial Direct Current Stimulation (tDCS) over the affected Parietal-Insular-Vestibular Cortex (PIVC) on seated posture of patients with lateropulsion following stroke. We hypothesized that bilateral electrode placement over PIVC (vs active control) would produce a change in seated posture. Background: Lateropulsion following stroke (Pusher Syndrome) is characterized by lateral displacement of subjective postural vertical toward the weak side. It is caused by lesions affecting vestibular projections to the Ventral Lateral Thalamus (VLT) or projections from the VLT to the Parietal-Insular-Vestibular Cortex (PIVC). Methods: Seventeen subjects with Burke Lateropulsion Scale scores ≥ 2 within 30 days of an ischemic stroke signed an IRB-approved consent. They received 2mA tDCS delivered using 25cm 2 saline soaked sponge electrodes via one of two montages: Test (anode over the affected PIVC and cathode opposite PIVC) versus Active Control (anode over the affected PIVC and cathode over the opposite supra-orbital region). PIVC was defined using EEG 10/20 coordinates. Seated medial-lateral center of pressure (COP-X) was measured using a custom-designed chair mounted on an AMTI™ analog-to-digital forceplate. An inclinometer strapped to the chest and aligned with the sternum measured lateral trunk tilt. Data were collected prior to, then at 5, 10, and 15 minutes during tDCS and 5 min following tDCS. Results: Repeated Measures Analysis of Variance rejected the hypothesis of an interaction between Montage and Time for: mean COP-X displacement (in) (Wilks’ λ F = 0.647 df =(4, 13), P = 0.639); mean speed of COP-X (in/s) (Wilks’ λ F = 0.740 df =(4, 13), P =0.581); mean inclinometer tilt (degrees) (Wilks’ λ F = 0.740 df =(4, 13), P =0.581). Conclusion: Neither tDCS montage showed improvement in COP-X displacement, COP-X movement velocity or inclinometer readings. These negative results are important to encourage the development of alternative tDCS stimulation parameters or identification of alternative cortical or vestibular tDCS targets for the treatment of Lateropulsion Following Stroke.

Surgery for Nontumoral Insular Epilepsy Explored by Stereoelectroencephalography.

Hidden by the perisylvian operculi, insular cortex has long been underexplored in the context of epilepsy surgery. Recent studies advocated stereoelectroencephalography (SEEG) as a reliable tool to explore insular cortex and its involvement in intractable epilepsy and suggested that insular seizures could be an underestimated entity. However, the results of insular resection to treat pharmacoresistant epilepsy are rarely reported. We report 6 consecutive cases of right insular resection performed based on anatomoelectroclinical correlations provided by SEEG. Six right-handed patients (3 male, 3 female) with drug-resistant epilepsy underwent comprehensive presurgical evaluation. Based on video electroencephalographic recordings, they all underwent SEEG evaluation with bilateral (n = 4) or unilateral right (n = 2) insular depth electrode placement. All patients had both orthogonal and oblique (1 anterior, 1 posterior) insular electrodes (n = 4-6 electrodes). Preoperative magnetic resonance imaging findings were normal in 4 patients, 1 patient had right insular focal cortical dysplasia, and 1 patient had a right opercular postoperative scar (cavernous angioma). All patients underwent right partial insular corticectomy via the subpial transopercular approach. Intracerebral recordings demonstrated an epileptogenic zone confined to the right insula in all patients. After selective insular resection, 5 of 6 patients were seizure free (Engel class I) with a mean follow-up of 36.2 months (range, 18-68 months). Histological findings revealed focal cortical dysplasia in 5 patients and a gliosis scar in 1 patient. All patients had minor transient neurological deficit (eg, facial paresis, dysarthria). Insular resection based on SEEG findings can be performed safely with a significant chance of seizure freedom. EEG, electroencephalographyEZ, epileptic zoneFCD, focal cortical dysplasiaILE, insular lobe epilepsySEEG, stereoelectroencephalography.