Publications by authors named "Fenoy A"

Article Synopsis
  • * It examines the neural networks involved in depression, the technical aspects of DBS, and reviews clinical trial outcomes while addressing safety and ethical issues.
  • * Finally, the chapter proposes future research directions for DBS, highlighting innovations like closed-loop systems and machine-learning approaches to improve study designs and efficacy.
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The history of amyotrophic lateral sclerosis (ALS)-also known as Charcot's disease, Lou Gehrig's disease, and motor neuron disease (MND)-freezes the texts of the scientist and physician Jean-Martin Charcot in a hagiographic narrative describing a brilliant discovery, based on the anatomo-clinical method. This narrative is often used by biologists and physicians as a reference point. This article shows that the use of the hagiographic register faces limitations.

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Deep brain stimulation (DBS) targeting the ventral intermediate (Vim) nucleus of the thalamus is an effective treatment for essential tremor (ET). We studied 15 ​ET patients undergoing DBS to a major input/output tract of the Vim, the dentato-rubro-thalamic tract (DRTt), using resting state functional MRI (rsfMRI) to evaluate connectivity differences between DBS ON and OFF and elucidate significant regions most influential in impacting tremor control and/or concomitant gait ataxia. Anatomical/functional 1.

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Subthalamic nucleus deep brain stimulation (STN-DBS) alleviates motor symptoms of Parkinson's disease (PD), thereby improving quality of life. However, quantitative brain markers to evaluate DBS responses and select suitable patients for surgery are lacking. Here, we used metabolic brain imaging to identify a reproducible STN-DBS network for which individual expression levels increased with stimulation in proportion to motor benefit.

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Background: Although deep brain stimulation (DBS) has established uses for patients with movement disorders and epilepsy, it is under consideration for a wide range of neurologic and neuropsychiatric conditions.

Objective: To review successful and unsuccessful DBS clinical trials and identify factors associated with early trial termination.

Methods: The ClinicalTrials.

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Major Depressive Disorder continues to remain one of the most prevalent psychiatric diseases globally. Despite multiple trials of conventional therapies, a subset of patients fail to have adequate benefit to treatment. Deep brain stimulation (DBS) is a promising treatment in this difficult to treat population and has shown strong antidepressant effects across multiple cohorts.

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Essential tremor DBS targeting the ventral intermediate nucleus (Vim) of the thalamus and its input, the dentato-rubro-thalamic tract (DRTt), has proven to be an effective treatment strategy. We examined thalamo-cortical evoked potentials (TCEPs) and cortical dynamics during stimulation of the DRTt. We recorded TCEPs in primary motor cortex during clinical and supra-clinical stimulation of the DRTt in ten essential tremor patients.

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Opioid dependence is a national crisis, with 30 million patients annually at risk of becoming persistent opioid users after receiving opioids for post-surgical pain management. Translational Pain Services (TPS) demonstrate effectiveness for behavioral health improvements but its effectiveness in preventing persistent opioid use is less established, especially amongst opioid exposed patients. Prohibitive costs and accessibility challenges have hindered TPS program adoption.

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Deep brain stimulation (DBS) to the superolateral branch of the medial forebrain bundle is an efficacious therapy for treatment-resistant depression, providing rapid antidepressant effects. In this study, we use F-fluorodeoxyglucose-positron emission tomography (PET) to identify brain metabolic changes over 12 months post-DBS implantation in ten of our patients, compared to baseline. The primary outcome measure was a 50% reduction in Montgomery-Åsberg Depression Rating Scale (MADRS) score, which was interpreted as a response.

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Article Synopsis
  • Deep brain stimulation (DBS) targeting the medial forebrain bundle shows promise as a treatment for therapy-resistant depression, with effects lasting up to 5 years in some patients.
  • The study tracked 10 patients, assessing improvements using the Montgomery-Åsberg Depression Rating Scale, with significant reductions in scores post-stimulation.
  • Key recommendations for future studies include extending the sham stimulation phase and integrating functional imaging to better understand treatment effects.
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Background: Methodological approaches to deep brain stimulation (DBS) continue to evolve from awake frame-based to asleep frameless procedures with robotic assistance, primarily directed to optimize operative efficiency, lead accuracy, and patient comfort. Comparison between the 2 is scarce.

Objective: To analyze the impacts of methodological differences on operative efficiency and stereotactic accuracy using a frame compared with a frameless robotic platform while maintaining the awake state and use of multiple microelectrode recording (MER) trajectories.

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While most patients with depression respond to pharmacotherapy and psychotherapy, about one-third will present treatment resistance to these interventions. For patients with treatment-resistant depression (TRD), invasive neurostimulation therapies such as vagus nerve stimulation, deep brain stimulation, and epidural cortical stimulation may be considered. We performed a narrative review of the published literature to identify papers discussing clinical studies with invasive neurostimulation therapies for TRD.

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Article Synopsis
  • Dystonia is a movement disorder that affects quality of life, and while Botulinum Neurotoxin (BoNT) is a common treatment, it doesn't work for all patients; deep brain stimulation (DBS) has also been shown to benefit those with dystonia.
  • A study of 67 dystonia patients treated with DBS over 7 years found significant improvements in symptoms, using scales like the Global Dystonia Severity (GDS) and Burke-Fahn-Marsden (BFMDRS) scores.
  • The results showed average reductions in scores 5 to 7 years post-DBS, indicating DBS is an effective long-term treatment for various types of dystonia, despite not completely eliminating symptoms.
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The medial forebrain bundle-a white matter pathway projecting from the ventral tegmental area-is a structure that has been under a lot of scrutinies recently due to its implications in the modulation of certain affective disorders such as major depression. In the following, we will discuss major depression in the context of being a disorder dependent on multiple relevant networks, the pathological performance of which is responsible for the manifestation of various symptoms of the disease which extend into emotional, motivational, physiological, and also cognitive domains of daily living. We will focus on the reward system, an evolutionarily conserved pathway whose underperformance leads to anhedonia and lack of motivation, which are key traits in depression.

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Article Synopsis
  • There is an ongoing debate about the effectiveness of intraoperative microelectrode recording (MER) in deep brain stimulation (DBS) for targeting areas like the subthalamic nucleus (STN) and globus pallidus (GPi).
  • A study at the University of Texas analyzed 90 lead implants from 46 patients and found a significant downward shift in lead coordinates during the surgery, indicating that MER can influence the final lead placement.
  • The research shows that using MER does not result in higher complication rates, as only a small percentage of patients experienced postoperative issues like seizures, suggesting that MER might enhance the reliability of lead positioning without increasing risks.
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Background: Postoperative cerebral edema around a deep brain stimulation (DBS) electrode is an uncommonly reported complication of DBS surgery. The etiology of this remains unknown, and the presentation is highly variable; however, the patients generally report a good outcome.

Case Description: Here, we report an unusual presentation of postoperative edema in a 66-year-old female who has bilateral dentatorubrothalamic tract (specifically, the ventral intermediate nucleus) DBS for a mixed type tremor disorder.

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Deep brain stimulation (DBS) of the medial forebrain bundle (MFB) displays a promising antidepressant effects in patients with treatment-refractory depression; however, a clear consensus on underlying mechanisms is still enigmatic. Herein, we investigated the effects of MFB-DBS on anhedonic-like behavior using the Froot Loops® consumption in a chronic unpredictable mild stress (CUS) model of depression, biochemical estimation of peripheral and central inflammatory cytokines, stress hormone, and brain-derived neurotrophic factor (BDNF). Seven days of MFB-DBS significantly reversed the 42-day CUS-generated anhedonic-like phenotype (p < 0.

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Background: Direct targeting of the dentato-rubro-thalamic tract is efficacious in DBS for tremor suppression.

Objectives: We sought to compare outcomes and optimal stimulation parameters for tremor control using the technique of directly targeting the dentato-rubro-thalamic tract to those who underwent indirect targeting of the ventral intermediate nucleus thalamus.

Methods: Twenty consecutive essential tremor patients obtained preoperative diffusion MRIs, where the dentato-rubro-thalamic tract was individually drawn and used to directly target the ventral intermediate nucleus of the thalamus during surgery.

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