156 research outputs found

    Subcallosal cingulate deep brain stimulation for treatment-resistant depression: a multi-site, randomized, sham-controlled trial

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    Background: Deep brain stimulation (DBS) of the subcallosal cingulate white matter (SCC) has shown promise as an intervention for patients with chronic, unremitting depression (TRD). To test the safety and efficacy of DBS for TRD, a prospective, randomized, sham-controlled trial was conducted. Methods: Participants with TRD were implanted with a DBS system targeting bilateral SCC white matter and randomized to six months of active versus sham DBS followed by six months open-label SCC DBS. The primary outcome was response rate at the end of the six-month double-blind phase. Response was defined as a 40% or greater reduction in depression severity from baseline. A futility analysis was performed when approximately half of the proposed sample received DBS implantation and completed the double-blind phase. At the conclusion of the 12-month study, a subset of patients continued to be followed for up to 24 months. Findings: Prior to the futility analysis, 90 participants were randomized to active (N=60) versus sham (N=30) stimulation. Both groups showed improvement, but there was no statistically significant difference in response rate during the double-blind, sham-controlled phase. Participants continued to improve during the six months open-label phase. Long-term response and remission rates for all participants receiving active DBS open-label were, respectively, 40% and 19% at 12 months, 51% and 17% at 18 months, and 48% and 25% at 24 months. Twenty-eight patients experienced 39 adverse events; eight of these (in seven patients) were deemed to be related to the study device and/or surgery. Interpretation: This study confirmed the safety and feasibility of SCC DBS as a treatment for TRD but failed to show statistically significant antidepressant efficacy in a six months double-blind, sham-controlled trial. Long-term (up to 24 months) open-label SCC DBS was associated with a response rate of nearly 50%, with 25% of participants remitted. These rates are clinically meaningful and higher than those expected in this patient population with treatment-as-usual

    A hybrid SVM/HMM based system for the state detection of individual finger movements from multichannel ECoG signals

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    A hybrid state detection algorithm is presented for the estimation of baseline and movement states which can be used to trigger a free paced neuroprostethic. The hybrid model was constructed by fusing a multiclass Support Vector Machine (SVM) with a Hidden Markov Model (HMM), where the internal hidden state observation probabilities were represented by the discriminative output of the SVM. The proposed method was applied to the multichannel Electrocorticogram (ECoG) recordings of BCI competition IV to identify the baseline and movement states while subjects were executing individual finger movements. The results are compared to regular Gaussian Mixture Model (GMM)-based HMM with the same number of states as SVM-based HMM structure. Our results indicate that the proposed hybrid state estimation method out-performs the standard HMM-based solution in all subjects studied with higher latency. The average latency of the hybrid decoder was approximately 290ms. © 2011 IEEE

    Extraction of sparse spatial filters using Oscillating Search

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    Common Spatial Pattern algorithm (CSP) is widely used in Brain Machine Interface (BMI) technology to extract features from dense electrode recordings by using their weighted linear combination. However, the CSP algorithm, is sensitive to variations in channel placement and can easily overfit to the data when the number of training trials is insufficient. Construction of sparse spatial projections where a small subset of channels is used in feature extraction, can increase the stability and generalization capability of the CSP method. The existing 0 norm based sub-optimal greedy channel reduction methods are either too complex such as Backward Elimination (BE) which provided best classification accuracies or have lower accuracy rates such as Recursive Weight Elimination (RWE) and Forward Selection (FS) with reduced complexity. In this paper, we apply the Oscillating Search (OS) method which fuses all these greedy search techniques to sparsify the CSP filters. We applied this new technique on EEG dataset IVa of BCI competition III. Our results indicate that the OS method provides the lowest classification error rates with low cardinality levels where the complexity of the OS is around 20 times lower than the BE. © 2012 IEEE

    Deep Brain Stimulation for Obsessive-Compulsive Disorder: Real World Experience Post-FDA-Humanitarian Use Device Approval

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    While case series have established the efficacy of deep brain stimulation (DBS) in treating obsessive-compulsive disorder (OCD), it has been our experience that few OCD patients present without comorbidities that affect outcomes associated with DBS treatment. Here we present our experience with DBS therapy for OCD in patients who all have comorbid disease, together with the results of our programming strategies. For this case series, we assessed five patients who underwent ventral capsule/ventral striatum (VC/VS) DBS for OCD between 2015 and 2019 at the University of Colorado Hospital. Every patient in this cohort exhibited comorbidities, including substance use disorders, eating disorder, tic disorder, and autism spectrum disorder. We conducted an IRB-approved, retrospective study of programming modifications and treatment response over the course of DBS therapy. In addition to patients\u27 subjective reports of improvement, we observed significant improvement in the Yale-Brown Obsessive-Compulsive Scale (44%), the Montgomery-Asberg Depression Rating Scale (53%), the Quality of Life Enjoyment and Satisfaction Questionnaire (27%), and the Hamilton Anxiety Rating scales (34.9%) following DBS. With respect to co-morbid disease, there was a significant improvement in a patient with tic disorder\u27s Total Tic Severity Score (TTSS) ( = 0.005). DBS remains an efficacious tool for the treatment of OCD, even in patients with significant comorbidities in whom DBS has not previously been investigated. Efficacious treatment results not only from the accurate placement of the electrodes by the surgeon but also from programming by the psychiatrist

    Feasibility of Using Ultra-High Field (7 T) MRI for Clinical Surgical Targeting

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    The advantages of ultra-high magnetic field (7 Tesla) MRI for basic science research and neuroscience applications have proven invaluable. Structural and functional MR images of the human brain acquired at 7 T exhibit rich information content with potential utility for clinical applications. However, (1) substantial increases in susceptibility artifacts, and (2) geometrical distortions at 7 T would be detrimental for stereotactic surgeries such as deep brain stimulation (DBS), which typically use 1.5 T images for surgical planning. Here, we explore whether these issues can be addressed, making feasible the use of 7 T MRI to guide surgical planning. Twelve patients with Parkinson's disease, candidates for DBS, were scanned on a standard clinical 1.5 T MRI and a 7 T MRI scanner. Qualitative and quantitative assessments of global and regional distortion were evaluated based on anatomical landmarks and transformation matrix values. Our analyses show that distances between identical landmarks on 1.5 T vs. 7 T, in the mid-brain region, were less than one voxel, indicating a successful co-registration between the 1.5 T and 7 T images under these specific imaging parameter sets. On regional analysis, the central part of the brain showed minimal distortion, while inferior and frontal areas exhibited larger distortion due to proximity to air-filled cavities. We conclude that 7 T MR images of the central brain regions have comparable distortions to that observed on a 1.5 T MRI, and that clinical applications targeting structures such as the STN, are feasible with information-rich 7 T imaging

    Results of endoscopic transsphenoidal pituitary surgery in 40 patients with a growth hormone-secreting macroadenoma

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    Contains fulltext : 96290.pdf (Publisher’s version ) (Open Access)OBJECTIVE: Transsphenoidal pituitary surgery (TS) is the primary treatment of choice for patients with acromegaly. Macroadenomas (>1 cm) are more difficult to resect than microadenomas (remission rate +/- 50% compared to +/- 90%). Besides the conventional microscopic TS, the more recently introduced endoscopic technique is nowadays frequently used. However, no large series reporting on its results have yet been published. We evaluated the outcome of endoscopic TS in 40 patients with a growth hormone (GH)-secreting macroadenoma treated in our hospital between 1998 and 2007. METHODS: Medical records were retrospectively reviewed. Remission was defined as disappearance of clinical symptoms of acromegaly, normal serum insulin-like growth factor-1 levels (</=2 SD) and serum GH levels suppressed to <2 mU/l after an oral glucose tolerance test within the first 4 months after TS. RESULTS: In four patients TS aimed at debulking of the tumour. In the remaining 36 patients, remission was achieved in 20 patients. In the first 5 years remission was achieved in 6 out of 18 patients (33%) compared to 14 out of 22 patients (63%) in the following 5 years (p = 0.06). Thirteen patients had a mild perioperative complication. Before TS 15 patients received hormonal substitution therapy compared to 12 patients (33%) after TS. CONCLUSION: Endoscopic TS is a good primary therapeutic option for patients with a GH-secreting macroadenoma, resulting in a remission rate of up to 63% in experienced hands. This technique can potentially improve the outcome of TS in these patients

    Comprehensive in vivo Mapping of the Human Basal Ganglia and Thalamic Connectome in Individuals Using 7T MRI

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    Basal ganglia circuits are affected in neurological disorders such as Parkinson's disease (PD), essential tremor, dystonia and Tourette syndrome. Understanding the structural and functional connectivity of these circuits is critical for elucidating the mechanisms of the movement and neuropsychiatric disorders, and is vital for developing new therapeutic strategies such as deep brain stimulation (DBS). Knowledge about the connectivity of the human basal ganglia and thalamus has rapidly evolved over recent years through non-invasive imaging techniques, but has remained incomplete because of insufficient resolution and sensitivity of these techniques. Here, we present an imaging and computational protocol designed to generate a comprehensive in vivo and subject-specific, three-dimensional model of the structure and connections of the human basal ganglia. High-resolution structural and functional magnetic resonance images were acquired with a 7-Tesla magnet. Capitalizing on the enhanced signal-to-noise ratio (SNR) and enriched contrast obtained at high-field MRI, detailed structural and connectivity representations of the human basal ganglia and thalamus were achieved. This unique combination of multiple imaging modalities enabled the in-vivo visualization of the individual human basal ganglia and thalamic nuclei, the reconstruction of seven white-matter pathways and their connectivity probability that, to date, have only been reported in animal studies, histologically, or group-averaged MRI population studies. Also described are subject-specific parcellations of the basal ganglia and thalamus into sub-territories based on their distinct connectivity patterns. These anatomical connectivity findings are supported by functional connectivity data derived from resting-state functional MRI (R-fMRI). This work demonstrates new capabilities for studying basal ganglia circuitry, and opens new avenues of investigation into the movement and neuropsychiatric disorders, in individual human subjects

    Deep brain stimulation for the treatment of substance use disorders: a promising approach requiring caution

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    Substance use disorders are prevalent, causing extensive morbidity and mortality worldwide. Evidence-based treatments are of low to moderate effect size. Growth in the neurobiological understanding of addiction (e.g., craving) along with technological advancements in neuromodulation have enabled an evaluation of neurosurgical treatments for substance use disorders. Deep brain stimulation (DBS) involves surgical implantation of leads into brain targets and subcutaneous tunneling to connect the leads to a programmable implanted pulse generator (IPG) under the skin of the chest. DBS allows direct testing of neurobiologically-guided hypotheses regarding the etiology of substance use disorders in service of developing more effective treatments. Early studies, although with multiple limitations, have been promising. Still the authors express caution regarding implementation of DBS studies in this population and emphasize the importance of safeguards to ensure patient safety and meaningful study results. In this perspectives article, we review lessons learned through the years of planning an ongoing trial of DBS for methamphetamine use disorder
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