80 results on '"Benjamin L. Walter"'
Search Results
2. MRI-based multivariate gray matter volumetric distance for predicting motor symptom progression in Parkinson's disease
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Anupa A. Vijayakumari, Hubert H. Fernandez, and Benjamin L. Walter
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Medicine ,Science - Abstract
Abstract While Parkinson's disease (PD)-related neurodegeneration is associated with structural changes in the brain, conventional magnetic resonance imaging (MRI) has proven less effective for clinical diagnosis due to its inability to reliably identify subtle changes early in the disease course. In this study, we aimed to develop a structural MRI-based biomarker to predict the rate of progression of motor symptoms in the early stages of PD. The study included 88 patients with PD and 120 healthy controls from the Parkinson's Progression Markers Initiative database; MRI at baseline and motor symptom scores assessed using the MDS-UPDRS-III at two time points (baseline and 48 months) were selected. Group-level volumetric analyses at baseline were not associated with the decline in motor functioning. Then, we developed a patient-specific multivariate gray matter volumetric distance and demonstrated that it could significantly predict changes in motor symptom scores (P
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- 2023
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3. Standardizing default electronic health record tools to improve safety for hospitalized patients with Parkinson’s disease
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Allan D. Wu, Benjamin L. Walter, Anne Brooks, Emily Buetow, Katherine Amodeo, Irene Richard, Kelly Mundth, and Hooman Azmi
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electronic health record ,Parkinson’s disease ,hospitalization ,safety ,Epic Systems ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Electronic Health Record (EHR) systems are often configured to address challenges and improve patient safety for persons with Parkinson’s disease (PWP). For example, EHR systems can help identify Parkinson’s disease (PD) patients across the hospital by flagging a patient’s diagnosis in their chart, preventing errors in medication and dosing through the use of clinical decision support, and supplementing staff education through care plans that provide step-by-step road maps for disease-based care of a specific patient population. However, most EHR-based solutions are locally developed and, thus, difficult to scale widely or apply uniformly across hospital systems. In 2020, the Parkinson’s Foundation, a national and international leader in PD research, education, and advocacy, and Epic, a leading EHR vendor with more than 35% market share in the United States, launched a partnership to reduce risks to hospitalized PWP using standardized EHR-based solutions. This article discusses that project which included leadership from physician informaticists, movement disorders specialists, hospital quality officers, the Parkinson’s Foundation and members of the Parkinson’s community. We describe the best practice solutions developed through this project. We highlight those that are currently available as standard defaults or options within the Epic EHR, discuss the successes and limitations of these solutions, and consider opportunities for scalability in environments beyond a single EHR vendor. The Parkinson’s Foundation and Epic launched a partnership to develop best practice solutions in the Epic EHR system to improve safety for PWP in the hospital. The goal of the partnership was to create the EHR tools that will have the greatest impact on outcomes for hospitalized PWP.
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- 2024
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4. Optimization of inpatient medication administration among persons with Parkinson’s disease: recommendations on pharmacy technology and workflow
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Jeryl Ritzi T. Yu, Brent S. Sokola, and Benjamin L. Walter
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Parkinson’s disease ,inpatient ,medication administration ,pharmacy ,recommendations ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Individuals with Parkinson’s disease (PD) are vulnerable during hospitalizations due to the underlying complexities o1f symptoms, and acute illness or medication changes often lead to decompensation. Complications during hospitalizations are often due to worsening motor and nonmotor symptoms and commonly result from inaccurate medication regimens. Although the accuracy of medication administration relies on an interplay of factors, including patient status, transitions of care, coordination between the hospital prescriber and outpatient neurologist, etc., hospital pharmacists play an integral role in pharmacotherapy. The main aspects of pharmacy strategies aim to achieve timely administration of levodopa-containing medications, reduction of substitution and omissions of antiparkinsonian medications, and avoidance of antidopaminergic medications. This paper highlights critical areas for improvement and recommendations to minimize the impact of other factors from the pharmacy standpoint.
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- 2023
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5. End of life care of hospitalized patients with Parkinson disease: a retrospective analysis and brief review
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Sakhi Bhansali, Ekhlas Assaedi, Jeryl Ritzi T. Yu, Nymisha Mandava, Claire Sonneborn, Olivia Hogue, Benjamin L. Walter, Renato V. Samala, and Adam Margolius
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parkinsonism ,Parkinson disease ,palliative care ,antipsychotic ,hospice ,DNR ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
BackgroundTowards the end of life (EOL), persons with parkinsonism (PwP) have complex needs and can present with unique palliative care (PC) challenges. There are no widely accepted guidelines to aid neurologists, hospitalists, or PC clinicians in managing the symptoms of PwP at EOL. We examined a population of PwP at EOL, aiming to describe trends of in-hospital management and utilization of PC services.MethodsAll PwP admitted to two hospitals during 2018 (N = 727) were examined retrospectively, assessing those who died in hospital or were discharged with hospice (EOL group, N = 35) and comparing them to the main cohort. Their demographics, clinical data, engagement of multidisciplinary and palliative services, code status changes, invasive care, frequency of admissions, and medication administration were assessed.ResultsAmong the EOL group, 8 expired in hospital, and 27 were discharged to hospice. Forty-six percent of EOL patients received a PC consultation during their admission. The median interval from admission to death was 37 days. Seventy-seven percent had a full code status on admission. Compared to hospice patients, those who expired in hospital had higher rates of invasive procedures and intensive care unit transfers (41% vs. 75%, in both variables), and lower rates of PC involvement (52% vs. 25%). The transition of code status change for the EOL group from Full code to Do Not Resuscitate (DNR) occurred at a median 4–5 days from admission. For patients that passed in the hospital, the median days from transition of code status to death was 0(IQR 0–1). Levodopa dose deviations were frequent in both EOL and non-EOL group, but contraindicated medications were infrequently administered (11% in EOL group vs. 9% in non-EOL group).ConclusionOur data suggest a low utilization of PC services and delayed discussions of goals of care. More work is needed to raise awareness of inpatient teams managing PwP regarding the unique but common challenges facing PwP with advanced disease. A brief narrative review summarizing the suggested management of symptoms common to hospitalized PwP near EOL is provided.
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- 2023
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6. The Parkinson’s disease waiting room of the future: measurements, not magazines
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Jay L. Alberts, Umar Shuaib, Hubert Fernandez, Benjamin L. Walter, David Schindler, Mandy Miller Koop, and Anson B. Rosenfeldt
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Parkinson’s disease ,technology enablement ,technology integration ,healthcare transformation ,clinical integration ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Utilizing technology to precisely quantify Parkinson’s disease motor symptoms has evolved over the past 50 years from single point in time assessments using traditional biomechanical approaches to continuous monitoring of performance with wearables. Despite advances in the precision, usability, availability and affordability of technology, the “gold standard” for assessing Parkinson’s motor symptoms continues to be a subjective clinical assessment as none of these technologies have been fully integrated into routine clinical care of Parkinson’s disease patients. To facilitate the integration of technology into routine clinical care, the Develop with Clinical Intent (DCI) model was created. The DCI model takes a unique approach to the development and integration of technology into clinical practice by focusing on the clinical problem to be solved by technology rather than focusing on the technology and then contemplating how it could be integrated into clinical care. The DCI model was successfully used to develop the Parkinson’s disease Waiting Room of the Future (WROTF) within the Center for Neurological Restoration at the Cleveland Clinic. Within the WROTF, Parkinson’s disease patients complete the self-directed PD-Optimize application on an iPad. The PD-Optimize platform contains cognitive and motor assessments to quantify PD symptoms that are difficult and time-consuming to evaluate clinically. PD-Optimize is completed by the patient prior to their medical appointment and the results are immediately integrated into the electronic health record for discussion with the movement disorder neurologist. Insights from the clinical use of PD-Optimize has spurred the development of a virtual reality technology to evaluate instrumental activities of daily living in PD patients. This new technology will undergo rigorous assessment and validation as dictated by the DCI model. The DCI model is intended to serve as a health enablement roadmap to formalize and accelerate the process of bringing the advantages of cutting-edge technology to those who could benefit the most: the patient.
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- 2023
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7. Author Correction: MRI-based multivariate gray matter volumetric distance for predicting motor symptom progression in Parkinson's disease
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Anupa A. Vijayakumari, Hubert H. Fernandez, and Benjamin L. Walter
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Medicine ,Science - Published
- 2023
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8. Digitizing a Therapeutic: Development of an Augmented Reality Dual-Task Training Platform for Parkinson’s Disease
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Jay L. Alberts, Ryan D. Kaya, Kathryn Scelina, Logan Scelina, Eric M. Zimmerman, Benjamin L. Walter, and Anson B. Rosenfeldt
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Parkinson’s disease (PD) ,dual-task ,augmented reality ,gait ,postural instability ,Chemical technology ,TP1-1185 - Abstract
Augmented reality (AR) may be a useful tool for the delivery of dual-task training. This manuscript details the development of the Dual-task Augmented Reality Treatment (DART) platform for individuals with Parkinson’s disease (PD) and reports initial feasibility, usability, and efficacy of the DART platform in provoking dual-task interference in individuals with PD. The DART platform utilizes the head-mounted Microsoft HoloLens2 AR device to deliver concurrent motor and cognitive tasks. Biomechanical metrics of gait and cognitive responses are automatically computed and provided to the supervising clinician. To assess feasibility, individuals with PD (N = 48) completed a bout of single-task and dual-task walking using the DART platform. Usability was assessed by the System Usability Scale (SUS). Dual-task interference was assessed by comparing single-task walking and walking during an obstacle course while performing a cognitive task. Average gait velocity decreased from 1.06 to 0.82 m/s from single- to dual-task conditions. Mean SUS scores were 81.3 (11.3), which placed the DART in the “good” to “excellent” category. To our knowledge, the DART platform is the first to use a head-mounted AR system to deliver a dual-task paradigm and simultaneously provide biomechanical data that characterize cognitive and motor performance. Individuals with PD were able to successfully use the DART platform with satisfaction, and dual-task interference was provoked. The DART platform should be investigated as a platform to treat dual-task declines associated with PD.
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- 2022
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9. Targeting neurons in the gastrointestinal tract to treat Parkinson's disease
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Robert A. Hauser, Dean Sutherland, Juan A. Madrid, Maria Angeles Rol, Steven Frucht, Stuart Isaacson, Fernando Pagan, Brian N. Maddux, George Li, Winona Tse, Benjamin L. Walter, Rajeev Kumar, Daniel Kremens, Mark F. Lew, Aaron Ellenbogen, Odinachi Oguh, Alberto Vasquez, William Kinney, Matt Lowery, Maria Resnick, Nicole Huff, Jerry Posner, Karla V. Ballman, Brian E. Harvey, Michael Camilleri, Michael Zasloff, and Denise Barbut
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Squalamine ,ENT-01 ,Parkinson's disease ,Constipation ,Treatment ,Non-motor ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Background: Parkinson's disease (PD) is associated with α-synuclein (αS) aggregation within the enteric nervous system (ENS) and constipation. Squalamine displaces proteins that are electrostatically bound to intracellular membranes and through this mechanism suppresses aggregation of αS monomers into neurotoxic oligomers. Objective: We sought to evaluate the safety of ENT-01 oral tablets (a synthetic squalamine salt), its pharmacokinetics, and its effect on bowel function in PD patients with constipation. Methods: In Stage 1, 10 patients received escalating single doses from 25 to 200 mg/day or maximum tolerated dose (MTD). In Stage 2, 34 patients received daily doses escalating from 75 to a maximum of 250 mg/day, a dose that induced change in bowel function or MTD, followed by a fixed dose for 7 days, and a 2-week washout. Primary efficacy endpoint was defined as an increase of 1 complete spontaneous bowel movement (CSBM)/week, or 3 CSBM/week over the baseline period, as defined by FDA guidelines for prokinetic agents. Safety was also assessed. Results: Over 80% of patients achieved the primary efficacy endpoint, with the mean number of CSBM/week increasing from 1.2 at baseline to 3.6 during fixed dosing (p = 1.2 × 10−7). Common adverse events included nausea in 21/44 (47%) and diarrhea in 18/44 (40%) patients. Systemic absorption was
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- 2019
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10. The International Deep Brain Stimulation Registry and Database for Gilles de la Tourette Syndrome: How Does it Work?
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Wissam eDeeb, Peter J. Rossi, Mauro ePorta, Veerle eVisser-Vandewalle, Domenico eServello, Peter eSilburn, Terry eCoyne, James F. Leckman, Thomas eFoltynie, Marwan eHariz, Eileen Maria Joyce, Ludvic eZrinzo, Zinovia eKefalopoulou, Marie-Laure eWelter, Carine eKarachi, Luc eMallet, JL eHoueto, Joohi eJimenez-Shahed, Fan-Geng eMeng, Bryan T. Klassen, Alon Y. Mogilner, Michael H. Pourfar, Jens eKuhn, L. eAckermans, Takanobu eKaido, Yasin eTemel, Robert E Gross, Harrison C. Walker, Andres M. Lozano, Suketu M. Khandhar, Benjamin L. Walter, Ellen eWalter, Zoltan eMari, Barbara Kelly Changizi, Elena eMoro, Juan Carlos eBaldermann, Daniel eHuys, S. Elizabeth eZauber, Lauren E. Schrock, Jian-guo eZhang, Wei eHu, Kelly Douglas Foote, Kyle eRizer, Jonathan W. Mink, Douglas W. Woods, Aysegul eGunduz, and Michael S. Okun
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Databases as Topic ,Deep Brain Stimulation ,Registries ,Tics ,Tourette Syndrome ,regulatory agencies ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Tourette Syndrome (TS) is a neuropsychiatric disease characterized by a combination of motor and vocal tics. Deep brain stimulation (DBS), already widely utilized for Parkinson’s disease and other movement disorders, is an emerging therapy for select and severe cases of TS that are resistant to medication and behavioral therapy. Over the last two decades, DBS has been used experimentally to manage severe TS cases. The results of case reports and small case series have been variable but in general positive. The reported interventions have, however, been variable, and there remain non-standardized selection criteria, various brain targets, differences in hardware, as well as variability in the programming parameters utilized. DBS centers perform only a handful of TS DBS cases each year, making large-scale outcomes difficult to study and to interpret. These limitations, coupled with the variable effect of surgery, and the overall small numbers of TS patients with implanted DBS worldwide, have delayed regulatory agency approval (e.g. FDA and equivalent agencies around the world). The Tourette Association of America, in response to the worldwide need for a more organized and collaborative effort, launched an international TS DBS registry and database. The main goal of the project has been to share data, uncover best practices, improve outcomes, and to provide critical information to regulatory agencies. The international registry and database has improved the communication and collaboration among TS DBS centers worldwide. In this paper we will review some of the key operation details for the international TS DBS database and registry.
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- 2016
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11. A Comparison of Intention Estimation Methods for Decoder Calibration in Intracortical Brain-Computer Interfaces.
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Francis R. Willett, Brian A. Murphy, Daniel Young, William D. Memberg, Christine H. Blabe, Chethan Pandarinath, Brian Franco, Jad Saab, Benjamin L. Walter, Jennifer A. Sweet, Jonathan P. Miller, Jaimie M. Henderson, Krishna V. Shenoy, John D. Simeral, Beata Jarosiewicz, Leigh R. Hochberg, Robert F. Kirsch, and A. Bolu Ajiboye
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- 2018
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12. Interim Safety Profile From the Feasibility Study of the BrainGate Neural Interface System
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Daniel B. Rubin, A. Bolu Ajiboye, Laurie Barefoot, Marguerite Bowker, Sydney S. Cash, David Chen, John P. Donoghue, Emad N. Eskandar, Gerhard Friehs, Carol Grant, Jaimie M. Henderson, Robert F. Kirsch, Rose Marujo, Maryam Masood, Stephen T. Mernoff, Jonathan P. Miller, Jon A. Mukand, Richard D. Penn, Jeremy Shefner, Krishna V. Shenoy, John D. Simeral, Jennifer A. Sweet, Benjamin L. Walter, Ziv M. Williams, and Leigh R. Hochberg
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Neurology (clinical) - Abstract
Background and ObjectivesBrain-computer interfaces (BCIs) are being developed to restore mobility, communication, and functional independence to people with paralysis. Though supported by decades of preclinical data, the safety of chronically implanted microelectrode array BCIs in humans is unknown. We report safety results from the prospective, open-label, nonrandomized BrainGate feasibility study (NCT00912041), the largest and longest-running clinical trial of an implanted BCI.MethodsAdults aged 18–75 years with quadriparesis from spinal cord injury, brainstem stroke, or motor neuron disease were enrolled through 7 clinical sites in the United States. Participants underwent surgical implantation of 1 or 2 microelectrode arrays in the motor cortex of the dominant cerebral hemisphere. The primary safety outcome was device-related serious adverse events (SAEs) requiring device explantation or resulting in death or permanently increased disability during the 1-year postimplant evaluation period. The secondary outcomes included the type and frequency of other adverse events and the feasibility of the BrainGate system for controlling a computer or other assistive technologies.ResultsFrom 2004 to 2021, 14 adults enrolled in the BrainGate trial had devices surgically implanted. The average duration of device implantation was 872 days, yielding 12,203 days of safety experience. There were 68 device-related adverse events, including 6 device-related SAEs. The most common device-related adverse event was skin irritation around the percutaneous pedestal. There were no safety events that required device explantation, no unanticipated adverse device events, no intracranial infections, and no participant deaths or adverse events resulting in permanently increased disability related to the investigational device.DiscussionThe BrainGate Neural Interface system has a safety record comparable with other chronically implanted medical devices. Given rapid recent advances in this technology and continued performance gains, these data suggest a favorable risk/benefit ratio in appropriately selected individuals to support ongoing research and development.Trial Registration InformationClinicalTrials.gov Identifier:NCT00912041.Classification of EvidenceThis study provides Class IV evidence that the neurosurgically placed BrainGate Neural Interface system is associated with a low rate of SAEs defined as those requiring device explantation, resulting in death, or resulting in permanently increased disability during the 1-year postimplant period.
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- 2023
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13. Web-Interface-Driven Development for Neuro3D, a Clinical Data Capture and Decision Support System for Deep Brain Stimulation.
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Shiqiang Tao, Benjamin L. Walter, Sisi Gu, and Guo-Qiang Zhang 0001
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- 2016
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14. Oral ENT-01 Targets Enteric Neurons to Treat Constipation in Parkinson Disease
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Michael Camilleri, Thyagarajan Subramanian, Fernando Pagan, Stuart Isaacson, Ramon Gil, Robert A. Hauser, Mary Feldman, Mark Goldstein, Rajeev Kumar, Daniel Truong, Nisha Chhabria, Benjamin L. Walter, Jonathan Eskenazi, Robert Riesenberg, Daniel Burdick, Winona Tse, Eric Molho, Bradley Robottom, Perminder Bhatia, Srinath Kadimi, Kevin Klos, David Shprecher, Otto Marquez-Mendoza, Gonzalo Hidalgo, Stephen Grill, George Li, Howard Mandell, Mary Hughes, Sharisse Stephenson, Joel Vandersluis, Michael Pfeffer, Andrew Duker, Vikram Shivkumar, William Kinney, James MacDougall, Michael Zasloff, and Denise Barbut
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Treatment Outcome ,Double-Blind Method ,Internal Medicine ,Humans ,Parkinson Disease ,Dementia ,General Medicine ,Defecation ,Constipation - Abstract
Parkinson disease (PD) is associated with α-synuclein (αS) aggregation within enteric neurons. ENT-01 inhibits the formation of αS aggregates and improved constipation in an open-label study in patients with PD.To evaluate the safety and efficacy of oral ENT-01 for constipation and neurologic symptoms in patients with PD and constipation.Randomized, placebo-controlled phase 2b study. (ClinicalTrials.gov: NCT03781791).Outpatient.150 patients with PD and constipation.ENT-01 or placebo daily for up to 25 days. After baseline assessment of constipation severity, daily dosing was escalated to the prokinetic dose, the maximum dose (250 mg), or the tolerability limit, followed by a washout period.The primary efficacy end point was the number of complete spontaneous bowel movements (CSBMs) per week. Neurologic end points included dementia (assessed using the Mini-Mental State Examination [MMSE]) and psychosis (assessed using the Scale for the Assessment of Positive Symptoms adapted for PD [SAPS-PD]).The weekly CSBM rate increased from 0.7 to 3.2 in the ENT-01 group versus 0.7 to 1.2 in the placebo group (Longer treatment periods need to be investigated in future studies.ENT-01 was safe and significantly improved constipation.Enterin, Inc.
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- 2022
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15. Directional Stimulation in Parkinson's Disease and Essential Tremor: The Cleveland Clinic Experience
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Binith Cheeran, Richard Rammo, Sarah J. Ozinga, Sean J. Nagel, Srivatsan Pallavaram, Andre G. Machado, Alexandra White, and Benjamin L. Walter
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Male ,medicine.medical_specialty ,Deep brain stimulation ,Parkinson's disease ,Deep Brain Stimulation ,Essential Tremor ,medicine.medical_treatment ,Thalamus ,Stimulation ,03 medical and health sciences ,0302 clinical medicine ,Physical medicine and rehabilitation ,Subthalamic Nucleus ,Humans ,Medicine ,Thalamic stimulator ,Retrospective Studies ,Essential tremor ,business.industry ,Parkinson Disease ,General Medicine ,medicine.disease ,Single segment ,Subthalamic nucleus ,Anesthesiology and Pain Medicine ,Neurology ,Neurology (clinical) ,business ,030217 neurology & neurosurgery - Abstract
OBJECTIVE To assess use of directional stimulation in Parkinson's disease and essential tremor patients programmed in routine clinical care. MATERIALS AND METHODS Patients with Parkinson's disease or essential tremor implanted at Cleveland Clinic with a directional deep brain stimulation (DBS) system from November 2017 to October 2019 were included in this retrospective case series. Omnidirectional was compared against directional stimulation using therapeutic current strength, therapeutic window percentage, and total electrical energy delivered as outcome variables. RESULTS Fifty-seven Parkinson's disease patients (36 males) were implanted in the subthalamic nucleus (105 leads) and 33 essential tremor patients (19 males) were implanted in the ventral intermediate nucleus of the thalamus (52 leads). Seventy-four percent of patients with subthalamic stimulation (65% of leads) and 79% of patients with thalamic stimulation (79% of leads) were programmed with directional stimulation for their stable settings. Forty-six percent of subthalamic leads and 69% of thalamic leads were programmed on single segment activation. There was no correlation between the length of microelectrode trajectory through the STN and use of directional stimulation. CONCLUSIONS Directional programming was more common than omnidirectional programming. Substantial gains in therapeutic current strength, therapeutic window, and total electrical energy were found in subthalamic and thalamic leads programmed on directional stimulation.
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- 2022
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16. A Method for Predicting the Outcomes of Combined Pharmacologic and Deep Brain Stimulation Therapy for Parkinson's Disease.
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Reuben R. Shamir, Trygve Dolber, Angela M. Noecker, Anneke M. M. Frankemolle, Benjamin L. Walter, and Cameron C. McIntyre
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- 2014
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17. Automated motion sensor quantification of gait and lower extremity bradykinesia.
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Dustin A. Heldman, Danielle E. Filipkowski, David E. Riley, Christina M. Whitney, Benjamin L. Walter, Steven A. Gunzler, Joseph P. Giuffrida, and Thomas O. Mera
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- 2012
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18. North American survey on impact of the COVID-19 pandemic shutdown on DBS care
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Jason M. Schwalb, Fedor Panov, Lin Zhang, Michele K. York, Joohi Jimenez-Shahed, Neepa Patel, Joshua M. Rosenow, John M. Bertoni, Sol De Jesus, Harini Sarva, Benjamin L. Walter, Zoltan Mari, James McInerney, and Mustafa S. Siddiqui
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Canada ,medicine.medical_specialty ,2019-20 coronavirus outbreak ,Deep brain stimulation ,Coronavirus disease 2019 (COVID-19) ,Deep Brain Stimulation ,Shutdown ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,medicine.medical_treatment ,DBS ,Article ,Preoperative Care ,Pandemic ,medicine ,Humans ,Neurologists ,Survey ,Electrode placement ,Postoperative Care ,Academic Medical Centers ,Movement Disorders ,business.industry ,COVID-19 ,Parkinson Disease ,Telemedicine ,United States ,Implantable Neurostimulators ,Neurosurgeons ,Neurology ,Health Care Surveys ,North America ,Quarantine ,Emergency medicine ,Neurology (clinical) ,Geriatrics and Gerontology ,business ,Institutional policy - Abstract
Background The initial COVID-19 pandemic shutdown led to the canceling of elective surgeries throughout most of the USA and Canada. Objective This survey was carried out on behalf of the Parkinson Study Group (PSG) to understand the impact of the shutdown on deep brain stimulation (DBS) practices in North America. Methods A survey was distributed through RedCap® to the members of the PSG Functional Neurosurgical Working Group. Only one member from each site was asked to respond to the survey. Responses were collected from May 15 to June 6, 2020. Results Twenty-three sites participated; 19 (83%) sites were from the USA and 4 (17%) from Canada. Twenty-one sites were academic medical centers. COVID-19 associated DBS restrictions were in place from 4 to 16 weeks. One-third of sites halted preoperative evaluations, while two-thirds of the sites offered limited preoperative evaluations. Institutional policy was the main contributor for the reported practice changes, with 87% of the sites additionally reporting patient-driven surgical delays secondary to pandemic concerns. Pre-post DBS associated management changes affected preoperative assessments 96%; electrode placement 87%; new implantable pulse generator (IPG) placement 83%; IPG replacement 65%; immediate postoperative DBS programming 74%; and routine DBS programming 91%. Conclusion The COVID-19 pandemic related shutdown resulted in DBS practice changes in almost all North American sites who responded to this large survey. Information learned could inform development of future contingency plans to reduce patient delays in care under similar circumstances.
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- 2021
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19. Addressing critical care gaps in inpatient Parkinson's care - Minimizing the impact of comorbidities and developing new care delivery models
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Jeryl Ritzi T. Yu and Benjamin L. Walter
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Hospitalization ,Inpatients ,Neurology ,Critical Care ,Humans ,Parkinson Disease ,Neurology (clinical) ,Geriatrics and Gerontology ,Delivery of Health Care - Published
- 2022
20. Estimating the Risk of Deep Brain Stimulation in the Modern Era: 2008 to 2020
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Arbaz Momin, Andre G. Machado, Sean J. Nagel, Joshua L. Golubovsky, Hubert H. Fernandez, Richard Rammo, Benjamin L. Walter, and Eun Jeong Koh
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medicine.medical_specialty ,Surgical complication ,Movement disorders ,Deep brain stimulation ,business.industry ,Deep Brain Stimulation ,medicine.medical_treatment ,Erosion rate ,United States ,Surgery ,Food and drug administration ,medicine ,Intracranial complication ,Humans ,Neurology (clinical) ,medicine.symptom ,business ,Complication ,Medical literature - Abstract
Background Deep brain stimulation (DBS) was first approved by the United States Food and Drug Administration in 1997. Although the fundamentals of DBS remain the same, hardware, software, and imaging have evolved significantly. Objective To test our hypothesis that the aggregate complication rate in the medical literature in the past 12 years would be lower than what is often cited based on early experience with DBS surgery. Methods PubMed, PsycINFO, and EMBASE were queried for studies from 2008 to 2020 that included patients treated with DBS from 2007 to 2019. This yielded 34 articles that evaluated all complications of DBS surgery, totaling 2249 patients. Results The overall complication rate in this study was 16.7% per patient. There was found to be a systemic complication rate of 0.89%, intracranial complication rate of 2.7%, neurological complication rate of 4.6%, hardware complication rate of 2.2%, and surgical site complication rate of 3.4%. The infection and erosion rate was 3.0%. Conclusion This review suggests that surgical complication rates have decreased since the first decade after DBS was first FDA approved. Understanding how to minimize complications from the inception of a technique should receive more attention.
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- 2021
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21. Can MRI-based multivariate gray matter volumetric distance predict motor progression and classify slow versus fast progressors in Parkinson’s disease?
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Anupa A Vijayakumari, Hubert H Fernandez, and Benjamin L Walter
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IntroductionWhile Parkinson’s disease (PD) related neurodegeneration is associated with structural changes in the brain, magnetic resonance imaging (MRI) has not been helpful in diagnosing PD or predicting the progression of motor symptoms. In this study, we aimed to develop a structural MRI-based biomarker to predict the rate of progression of motor symptoms and to classify patients based on the symptom severity (i.e. slow vs. fast progressors) in the early stages of PD.MethodsThe study included 59 patients with PD (n=40 for the primary analysis, 19 for the validation analysis), and 55 healthy controls with structural MRI from the Parkinson’s Progression Markers Initiative (PPMI) database. We developed a patient-specific multivariate gray matter volumetric distance using Mahalanobis distance (MGMV) to investigate the changes in MGMVover time using longitudinal linear mixed-effect model, its potential as a biomarker to predict the rate of progression of motor function (MDS-UPDRS-part III) using multiple linear regression model, and classification of patients based on symptom severity using machine learning (ML).ResultsMGMVat BL significantly predicted changes in motor severity (pGMVover time (p = 0.09) were noted. We obtained 85% accuracy in discriminating patients according to their symptom severity, and on an independent test cohort, an accuracy of 90% was achieved.ConclusionsWe identified a promising structural MRI-based biomarker for predicting the rate of progression of motor symptoms and classification of patients based on motor symptom severity.
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- 2022
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22. Targeting neurons in the gastrointestinal tract to treat Parkinson's disease
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Karla V. Ballman, Alberto Vasquez, Juan Antonio Madrid, Denise Barbut, Steven J. Frucht, Matt Lowery, Brian E. Harvey, Michael Zasloff, Maria Resnick, Mark F. Lew, William A. Kinney, Nicole Huff, Robert A. Hauser, Aaron Ellenbogen, Dean Sutherland, Maria Angeles Rol, Winona Tse, Odinachi Oguh, Rajeev Kumar, Brian N. Maddux, Daniel Kremens, Jerry Posner, Benjamin L. Walter, Michael Camilleri, Stuart Isaacson, George Li, and Fernando Pagan
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medicine.medical_specialty ,Parkinson's disease ,Constipation ,Nausea ,ENT-01 ,Gastroenterology ,lcsh:RC346-429 ,chemistry.chemical_compound ,Pharmacokinetics ,Internal medicine ,medicine ,Adverse effect ,lcsh:Neurology. Diseases of the nervous system ,Synuclein ,Squalamine ,business.industry ,General Medicine ,medicine.disease ,Treatment ,Diarrhea ,chemistry ,Non-motor ,Defecation ,Original Article ,medicine.symptom ,business - Abstract
Background Parkinson's disease (PD) is associated with α-synuclein (αS) aggregation within the enteric nervous system (ENS) and constipation. Squalamine displaces proteins that are electrostatically bound to intracellular membranes and through this mechanism suppresses aggregation of αS monomers into neurotoxic oligomers. Objective We sought to evaluate the safety of ENT-01 oral tablets (a synthetic squalamine salt), its pharmacokinetics, and its effect on bowel function in PD patients with constipation. Methods In Stage 1, 10 patients received escalating single doses from 25 to 200 mg/day or maximum tolerated dose (MTD). In Stage 2, 34 patients received daily doses escalating from 75 to a maximum of 250 mg/day, a dose that induced change in bowel function or MTD, followed by a fixed dose for 7 days, and a 2-week washout. Primary efficacy endpoint was defined as an increase of 1 complete spontaneous bowel movement (CSBM)/week, or 3 CSBM/week over the baseline period, as defined by FDA guidelines for prokinetic agents. Safety was also assessed. Results Over 80% of patients achieved the primary efficacy endpoint, with the mean number of CSBM/week increasing from 1.2 at baseline to 3.6 during fixed dosing (p = 1.2 × 10−7). Common adverse events included nausea in 21/44 (47%) and diarrhea in 18/44 (40%) patients. Systemic absorption was Conclusions Orally administered ENT-01 was safe and significantly improved bowel function in PD, suggesting that the ENS is not irreversibly damaged in PD. Minimal systemic absorption suggests that improvements result from local stimulation of the ENS. A double-blind, placebo-controlled study is now ongoing.
- Published
- 2019
23. Neural Representation of Observed, Imagined, and Attempted Grasping Force in Motor Cortex of Individuals with Chronic Tetraplegia
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Jaimie M. Henderson, Jennifer A. Sweet, A Bolu Ajiboye, Krishna V. Shenoy, Douglas C. Crowder, Leigh R. Hochberg, Benjamin L. Walter, Paymon Rezaii, Jonathan P. Miller, Jad Saab, Robert F. Kirsch, Francis R. Willett, Sydney S. Cash, Brian A Murphy, Jessica Abreu, Brian Franco, Anisha Rastogi, Sergey D. Stavisky, William D. Memberg, and Carlos E. Vargas-Irwin
- Subjects
Male ,Volition ,0301 basic medicine ,Neural Prostheses ,lcsh:Medicine ,Kinematics ,Somatosensory system ,Synaptic Transmission ,0302 clinical medicine ,lcsh:Science ,Tetraplegia ,Multidisciplinary ,Hand Strength ,Rehabilitation ,Motor Cortex ,Representation (systemics) ,Middle Aged ,Object (philosophy) ,Biomechanical Phenomena ,medicine.anatomical_structure ,Neurology ,Brain-Computer Interfaces ,Neurological ,Imagination ,Psychology ,Motor cortex ,Cognitive psychology ,1.1 Normal biological development and functioning ,Biomedical Engineering ,Bioengineering ,Quadriplegia ,Article ,03 medical and health sciences ,Underpinning research ,medicine ,Humans ,lcsh:R ,Work (physics) ,Neurosciences ,Recovery of Function ,Brain-machine interface ,medicine.disease ,Physical Rehabilitation ,030104 developmental biology ,Action (philosophy) ,Chronic Disease ,lcsh:Q ,Microelectrodes ,030217 neurology & neurosurgery - Abstract
Hybrid kinetic and kinematic intracortical brain-computer interfaces (iBCIs) have the potential to restore functional grasping and object interaction capabilities in individuals with tetraplegia. This requires an understanding of how kinetic information is represented in neural activity, and how this representation is affected by non-motor parameters such as volitional state (VoS), namely, whether one observes, imagines, or attempts an action. To this end, this work investigates how motor cortical neural activity changes when three human participants with tetraplegia observe, imagine, and attempt to produce three discrete hand grasping forces with the dominant hand. We show that force representation follows the same VoS-related trends as previously shown for directional arm movements; namely, that attempted force production recruits more neural activity compared to observed or imagined force production. Additionally, VoS-modulated neural activity to a greater extent than grasping force. Neural representation of forces was lower than expected, possibly due to compromised somatosensory pathways in individuals with tetraplegia, which have been shown to influence motor cortical activity. Nevertheless, attempted forces (but not always observed or imagined forces) could be decoded significantly above chance, thereby potentially providing relevant information towards the development of a hybrid kinetic and kinematic iBCI.
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- 2020
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24. Neuromodulation in multiple sclerosis
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Hesham Abboud, Benjamin L. Walter, Junaid Siddiqui, Eddie Hill, and Alessandro Serra
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030506 rehabilitation ,medicine.medical_specialty ,Multiple Sclerosis ,Deep brain stimulation ,Deep Brain Stimulation ,medicine.medical_treatment ,03 medical and health sciences ,0302 clinical medicine ,Physical medicine and rehabilitation ,Trigeminal neuralgia ,medicine ,Humans ,Functional electrical stimulation ,Spasticity ,Infusions, Spinal ,Neurorehabilitation ,Spinal Cord Stimulation ,Muscle Relaxants, Central ,business.industry ,Multiple sclerosis ,Infusion Pumps, Implantable ,medicine.disease ,Transcranial Magnetic Stimulation ,Neuromodulation (medicine) ,Transcranial magnetic stimulation ,Neurology ,Brain-Computer Interfaces ,Transcutaneous Electric Nerve Stimulation ,Neurology (clinical) ,medicine.symptom ,0305 other medical science ,business ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Neuromodulation, or the utilization of advanced technology for targeted electrical or chemical neuronal stimulation or inhibition, has been expanding in several neurological subspecialties. In the past decades, immune-modulating therapy has been the main focus of multiple sclerosis (MS) research with little attention to neuromodulation. However, with the recent advances in disease-modifying therapies, it is time to shift the focus of MS research to neuromodulation and restoration of function as with other neurological subspecialties. Preliminary research supports the value of intrathecal baclofen pump and functional electrical stimulation in improving spasticity and motor function in MS patients. Deep brain stimulation can improve MS-related tremor and trigeminal neuralgia. Spinal cord stimulation has been shown to be effective against MS-related pain and bladder dysfunction. Bladder overactivity also responds to sacral neuromodulation and posterior tibial nerve stimulation. Despite limited data in MS, transcranial magnetic stimulation and brain–computer interface are promising neuromodulatory techniques for symptom mitigation and neurorehabilitation of MS patients. In this review, we provide an overview of the available neuromodulatory techniques and the evidence for their use in MS.
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- 2017
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25. Restoration of reaching and grasping movements through brain-controlled muscle stimulation in a person with tetraplegia: a proof-of-concept demonstration
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William D. Memberg, P. Hunter Peckham, Michael W. Keith, Daniel R. Young, John P. Donoghue, Jonathan P. Miller, Benjamin L. Walter, Leigh R. Hochberg, Francis R. Willett, Jennifer A. Sweet, A Bolu Ajiboye, John D. Simeral, Brian A Murphy, Harry A. Hoyen, and Robert F. Kirsch
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0301 basic medicine ,medicine.medical_specialty ,Neuroprosthetics ,business.industry ,General Medicine ,medicine.disease ,3. Good health ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Physical medicine and rehabilitation ,medicine.anatomical_structure ,Hand strength ,Physical therapy ,Medicine ,Functional electrical stimulation ,business ,Veterans Affairs ,Tetraplegia ,Spinal cord injury ,030217 neurology & neurosurgery ,Brain–computer interface ,Motor cortex - Abstract
Summary Background People with chronic tetraplegia, due to high-cervical spinal cord injury, can regain limb movements through coordinated electrical stimulation of peripheral muscles and nerves, known as functional electrical stimulation (FES). Users typically command FES systems through other preserved, but unrelated and limited in number, volitional movements (eg, facial muscle activity, head movements, shoulder shrugs). We report the findings of an individual with traumatic high-cervical spinal cord injury who coordinated reaching and grasping movements using his own paralysed arm and hand, reanimated through implanted FES, and commanded using his own cortical signals through an intracortical brain–computer interface (iBCI). Methods We recruited a participant into the BrainGate2 clinical trial, an ongoing study that obtains safety information regarding an intracortical neural interface device, and investigates the feasibility of people with tetraplegia controlling assistive devices using their cortical signals. Surgical procedures were performed at University Hospitals Cleveland Medical Center (Cleveland, OH, USA). Study procedures and data analyses were performed at Case Western Reserve University (Cleveland, OH, USA) and the US Department of Veterans Affairs, Louis Stokes Cleveland Veterans Affairs Medical Center (Cleveland, OH, USA). The study participant was a 53-year-old man with a spinal cord injury (cervical level 4, American Spinal Injury Association Impairment Scale category A). He received two intracortical microelectrode arrays in the hand area of his motor cortex, and 4 months and 9 months later received a total of 36 implanted percutaneous electrodes in his right upper and lower arm to electrically stimulate his hand, elbow, and shoulder muscles. The participant used a motorised mobile arm support for gravitational assistance and to provide humeral abduction and adduction under cortical control. We assessed the participant's ability to cortically command his paralysed arm to perform simple single-joint arm and hand movements and functionally meaningful multi-joint movements. We compared iBCI control of his paralysed arm with that of a virtual three-dimensional arm. This study is registered with ClinicalTrials.gov, number NCT00912041. Findings The intracortical implant occurred on Dec 1, 2014, and we are continuing to study the participant. The last session included in this report was Nov 7, 2016. The point-to-point target acquisition sessions began on Oct 8, 2015 (311 days after implant). The participant successfully cortically commanded single-joint and coordinated multi-joint arm movements for point-to-point target acquisitions (80–100% accuracy), using first a virtual arm and second his own arm animated by FES. Using his paralysed arm, the participant volitionally performed self-paced reaches to drink a mug of coffee (successfully completing 11 of 12 attempts within a single session 463 days after implant) and feed himself (717 days after implant). Interpretation To our knowledge, this is the first report of a combined implanted FES+iBCI neuroprosthesis for restoring both reaching and grasping movements to people with chronic tetraplegia due to spinal cord injury, and represents a major advance, with a clear translational path, for clinically viable neuroprostheses for restoration of reaching and grasping after paralysis. Funding National Institutes of Health, Department of Veterans Affairs.
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- 2017
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26. Tremor in chronic inflammatory demyelinating polyneuropathy: Proof of unifying network model for dystonia
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Nataliya, Pyatka, Alexey, Sedov, Benjamin L, Walter, Hyder A, Jinnah, and Aasef G, Shaikh
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Male ,Superior Colliculi ,Polyradiculoneuropathy, Chronic Inflammatory Demyelinating ,Dystonic Disorders ,Models, Neurological ,Tremor ,Humans ,Middle Aged ,Nerve Net ,Proprioception - Abstract
Traditional hypotheses for the pathogenesis of dystonia, the third most common movement disorder, have focused primarily on the basal ganglia. Contemporary theories have emphasized the role of the cerebellum. The modulation of peripheral proprioception also affects dystonia. We proposed a unifying network model for dystonia where the cerebellum, basal ganglia, and peripheral proprioception are connected in a circuit that forms the neural integrator network, ensuring steady position. We suggested that impairment anywhere along this circuit leads to common phenomenology-slow drifts followed by corrective movements, resembling dystonic tremor. We tested this concept in a patient with chronic inflammatory demyelinating polyneuropathy with resulting abnormal proprioception. Quantitative assessment of tremor in this patient revealed drifts in limb position followed by corrective movements and superimposed sinusoidal oscillations-consistent with neural integrator dysfunction. This unique case of chronic inflammatory demyelinating polyneuropathy describes the role of proprioception on the unifying network model for dystonia.
- Published
- 2019
27. Principled BCI Decoder Design and Parameter Selection Using a Feedback Control Model
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Sergey D. Stavisky, Beata Jarosiewicz, Paymon Rezaii, Krishna V. Shenoy, Jad Saab, Benjamin L. Walter, Jonathan P. Miller, Leigh R. Hochberg, Chethan Pandarinath, John D. Simeral, Francis R. Willett, Christine H Blabe, Jaimie M. Henderson, Robert F. Kirsch, William D. Memberg, Brian A Murphy, Daniel R. Young, Jennifer A. Sweet, and A Bolu Ajiboye
- Subjects
0301 basic medicine ,Interface (computing) ,Models, Neurological ,lcsh:Medicine ,Biofeedback ,Bioengineering ,Article ,03 medical and health sciences ,0302 clinical medicine ,Models ,Clinical Research ,Humans ,Psychology ,lcsh:Science ,Brain–computer interface ,Multidisciplinary ,lcsh:R ,Biofeedback, Psychology ,Function (mathematics) ,Brain-machine interface ,16. Peace & justice ,Task (computing) ,030104 developmental biology ,Brain-Computer Interfaces ,Calibration ,Neurological ,Motor cortex ,lcsh:Q ,Algorithm ,030217 neurology & neurosurgery ,Psychomotor Performance ,Algorithms - Abstract
Decoders optimized offline to reconstruct intended movements from neural recordings sometimes fail to achieve optimal performance online when they are used in closed-loop as part of an intracortical brain-computer interface (iBCI). This is because typical decoder calibration routines do not model the emergent interactions between the decoder, the user, and the task parameters (e.g. target size). Here, we investigated the feasibility of simulating online performance to better guide decoder parameter selection and design. Three participants in the BrainGate2 pilot clinical trial controlled a computer cursor using a linear velocity decoder under different gain (speed scaling) and temporal smoothing parameters and acquired targets with different radii and distances. We show that a user-specific iBCI feedback control model can predict how performance changes under these different decoder and task parameters in held-out data. We also used the model to optimize a nonlinear speed scaling function for the decoder. When used online with two participants, it increased the dynamic range of decoded speeds and decreased the time taken to acquire targets (compared to an optimized standard decoder). These results suggest that it is feasible to simulate iBCI performance accurately enough to be useful for quantitative decoder optimization and design.
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- 2019
28. Predictors of second-sided deep brain stimulation for Parkinson's disease
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Leonardo A. Frizon, Hong Li, Andre G. Machado, Arbaz Momin, Maxwell Y. Lee, Olivia Hogue, Joshua L. Golubovsky, Sean J. Nagel, Jianning Shao, and Benjamin L. Walter
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medicine.medical_specialty ,Levodopa ,Parkinson's disease ,Deep brain stimulation ,Essential tremor ,Proportional hazards model ,business.industry ,medicine.medical_treatment ,Retrospective cohort study ,General Medicine ,medicine.disease ,Surgery ,03 medical and health sciences ,0302 clinical medicine ,Rating scale ,030220 oncology & carcinogenesis ,Cohort ,medicine ,business ,030217 neurology & neurosurgery ,medicine.drug - Abstract
OBJECTIVEParkinson’s disease (PD) is a progressive neurological movement disorder that is commonly treated with deep brain stimulation (DBS) surgery in advanced stages. The purpose of this study was to investigate factors that affect time to placement of a second-sided DBS lead for PD when a unilateral lead is initially placed for asymmetrical presentation. The decision whether to initially perform unilateral or bilateral DBS is largely based on physician and/or patient preference.METHODSThis study was a retrospective cohort analysis of patients with PD undergoing initial unilateral DBS for asymmetrical disease between January 1999 and December 2017 at the authors’ institution. Patients treated with DBS for essential tremor or other conditions were excluded. Variables collected included demographics at surgery, time since diagnosis, Unified Parkinson’s Disease Rating Scale motor scores (UPDRS-III), patient-reported quality-of-life outcomes, side of operation, DBS target, intraoperative complications, and date of follow-up. Paired t-tests were used to assess mean changes in UPDRS-III. Cox proportional hazards analysis and the Kaplan-Meier method were used to determine factors associated with time to second lead insertion over 5 years.RESULTSThe final cohort included 105 patients who underwent initial unilateral DBS for asymmetrical PD; 59% of patients had a second-sided lead placed within 5 years with a median time of 34 months. Factors found to be significantly associated with early second-sided DBS included patient age 65 years or younger, globus pallidus internus (GPi) target, and greater off-medication reduction in UPDRS-III score following initial surgery. Older age was also found to be associated with a smaller preoperative UPDRS-III levodopa responsiveness score and with a smaller preoperative to postoperative medication-off UPDRS-III change.CONCLUSIONSYounger patients, those undergoing GPi-targeted unilateral DBS, and patients who responded better to the initial DBS were more likely to undergo early second-sided lead placement. Therefore, these patients, and patients who are more responsive to medication preoperatively (as a proxy for DBS responsiveness), may benefit from consideration of initial bilateral DBS.
- Published
- 2019
29. Tremor in chronic inflammatory demyelinating polyneuropathy: Proof of unifying network model for dystonia
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Aasef G. Shaikh, Benjamin L. Walter, Hyder A. Jinnah, Alexey Sedov, and Nataliya Pyatka
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Dystonia ,Cerebellum ,Proprioception ,business.industry ,Eye movement ,Chronic inflammatory demyelinating polyneuropathy ,medicine.disease ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,Basal ganglia ,medicine ,Quantitative assessment ,Dystonic tremor ,business ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Traditional hypotheses for the pathogenesis of dystonia, the third most common movement disorder, have focused primarily on the basal ganglia. Contemporary theories have emphasized the role of the cerebellum. The modulation of peripheral proprioception also affects dystonia. We proposed a unifying network model for dystonia where the cerebellum, basal ganglia, and peripheral proprioception are connected in a circuit that forms the neural integrator network, ensuring steady position. We suggested that impairment anywhere along this circuit leads to common phenomenology-slow drifts followed by corrective movements, resembling dystonic tremor. We tested this concept in a patient with chronic inflammatory demyelinating polyneuropathy with resulting abnormal proprioception. Quantitative assessment of tremor in this patient revealed drifts in limb position followed by corrective movements and superimposed sinusoidal oscillations-consistent with neural integrator dysfunction. This unique case of chronic inflammatory demyelinating polyneuropathy describes the role of proprioception on the unifying network model for dystonia.
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- 2019
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30. The Neural Representation of Force across Grasp Types in Motor Cortex of Humans with Tetraplegia
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Benjamin L. Walter, Jessica Abreu, Sergey D. Stavisky, Krishna V. Shenoy, Paymon Rezaii, Jonathan P. Miller, Leigh R. Hochberg, A. Bolu Ajiboye, Brian A Murphy, Anisha Rastogi, Francis R. Willett, Jaimie M. Henderson, Carlos E. Vargas-Irwin, Robert F. Kirsch, William D. Memberg, Douglas C. Crowder, and Jennifer A. Sweet
- Subjects
grasp ,Computer science ,1.1 Normal biological development and functioning ,kinetic ,Bioengineering ,Quadriplegia ,Underpinning research ,motor cortex ,medicine ,Humans ,Tetraplegia ,Brain–computer interface ,Hand Strength ,business.industry ,General Neuroscience ,Rehabilitation ,brain-computer interface ,GRASP ,Work (physics) ,Motor Cortex ,Neurosciences ,Representation (systemics) ,Pattern recognition ,General Medicine ,Hand ,medicine.disease ,Object (computer science) ,Physical Rehabilitation ,medicine.anatomical_structure ,Neurological ,Sensory and Motor Systems ,Artificial intelligence ,business ,force ,Research Article: New Research ,Decoding methods ,Motor cortex - Abstract
Intracortical brain-computer interfaces (iBCIs) have the potential to restore hand grasping and object interaction to individuals with tetraplegia. Optimal grasping and object interaction require simultaneous production of both force and grasp outputs. However, since overlapping neural populations are modulated by both parameters, grasp type could affect how well forces are decoded from motor cortex in a closed-loop force iBCI. Therefore, this work quantified the neural representation and offline decoding performance of discrete hand grasps and force levels in two participants with tetraplegia. Participants attempted to produce three discrete forces (light, medium, hard) using up to five hand grasp configurations. A two-way Welch ANOVA was implemented on multiunit neural features to assess their modulation to force and grasp. Demixed principal component analysis was used to assess for population-level tuning to force and grasp and to predict these parameters from neural activity. Three major findings emerged from this work: 1) Force information was neurally represented and could be decoded across multiple hand grasps (and, in one participant, across attempted elbow extension as well); 2) Grasp type affected force representation within multi-unit neural features and offline force classification accuracy; and 3) Grasp was classified more accurately and had greater population-level representation than force. These findings suggest that force and grasp have both independent and interacting representations within cortex, and that incorporating force control into real-time iBCI systems is feasible across multiple hand grasps if the decoder also accounts for grasp type.Significance StatementIntracortical brain-computer interfaces (iBCIs) have emerged as a promising technology to potentially restore hand grasping and object interaction in people with tetraplegia. This study is among the first to quantify the degree to which hand grasp affects force-related – or kinetic – neural activity and decoding performance in individuals with tetraplegia. The study results enhance our overall understanding of how the brain encodes kinetic parameters across varying kinematic behaviors -- and in particular, the degree to which these parameters have independent versus interacting neural representations. Such investigations are a critical first step to incorporating force control into human-operated iBCI systems, which would move the technology towards restoring more functional and naturalistic tasks.
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- 2021
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31. Optimizing extended-release carbidopa/levodopa in Parkinson disease
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Benjamin L. Walter, Lawrence Elmer, Cheryl Waters, Fernando Pagan, Pinky Agarwal, John C. Morgan, William G. Ondo, Dee E. Silver, Kevin Klos, Alberto J. Espay, and Rohit Dhall
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0301 basic medicine ,medicine.medical_specialty ,Levodopa ,Movement disorders ,business.industry ,Disease ,Carbidopa/levodopa ,Gastroenterology ,3. Good health ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Pharmacotherapy ,Pharmacokinetics ,Dyskinesia ,Internal medicine ,Carbidopa ,Medicine ,Neurology (clinical) ,medicine.symptom ,business ,030217 neurology & neurosurgery ,medicine.drug - Abstract
Purpose of review:To help clinicians optimize the conversion of a patient's Parkinson disease pharmacotherapy from immediate-release carbidopa/levodopa (IR CD/LD) to an extended-release formulation (ER CD/LD).Recent findings:Eleven movement disorders specialists achieved consensus positions on the modification of trial-based conversion guidelines to suit individual patients in clinical practice.Summary:Because the pharmacokinetics of ER CD/LD differ from those of IR CD/LD, modification of dosage and dosing frequency are to be expected. Initial regimens may be based on doubling the patient's preconversion levodopa daily dosage and choosing a division of doses to address the patient's motor complications, e.g., wearing-off (warranting a relatively high ER CD/LD dose, possibly at a lower frequency than for IR CD/LD) or dyskinesia (warranting a relatively low dose, perhaps at an unchanged frequency). Patients should know that the main goal of conversion is a steadier levodopa clinical response, even if dosing frequency is unchanged.
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- 2016
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32. Test and Validation of a Smart Exercise Bike for Motor Rehabilitation in Individuals With Parkinson’s Disease
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Fred M. Discenzo, Robert S. Phillips, Benjamin L. Walter, Hassan Mohammadi-Abdar, Angela L. Ridgel, and Kenneth A. Loparo
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0209 industrial biotechnology ,medicine.medical_specialty ,medicine.medical_treatment ,Biomedical Engineering ,02 engineering and technology ,Approximate entropy ,Article ,03 medical and health sciences ,020901 industrial engineering & automation ,0302 clinical medicine ,Physical medicine and rehabilitation ,Heart rate ,Linear regression ,Internal Medicine ,medicine ,Humans ,Neurorehabilitation ,Movement Disorders ,Rehabilitation ,General Neuroscience ,Neurological Rehabilitation ,Parkinson Disease ,Equipment Design ,Robotics ,Exercise Therapy ,Equipment Failure Analysis ,Sample entropy ,Treatment Outcome ,Therapy, Computer-Assisted ,Exercise Test ,Physical therapy ,Cadence ,Psychology ,Cycling ,030217 neurology & neurosurgery - Abstract
To assess and validate the Smart Exercise Bike designed for Parkinson's Disease (PD) rehabilitation, 47 individuals with PD were randomly assigned to either the static or dynamic cycling group, and completed three sessions of exercise. Heart rate, cadence and power data were captured and recorded for each patient during exercise. Motor function for each subject was assessed with the UPDRS Motor III test before and after the three exercise sessions to evaluate the effect of exercise on functional abilities. Individuals who completed three sessions of dynamic cycling showed an average of 13.8% improvement in the UPDRS, while individuals in the static cycling group worsened by 1.6% in UPDRS. To distinguish the static and dynamic cycling groups by biomechanical and physiological features, the complexity of the recorded signals (cadence, power, and heart rate) was examined using approximate entropy (ApEn), sample entropy (SaEn) and spectral entropy (SpEn) as measures of variability. A multiple linear regression (MLR) model was used to relate these features to changes in motor function as measured by the UPDRS Motor III scale. Pattern variability in cadence was greater in the dynamic group when compared to the static group. In contrast, variability in power was greater for the static group. UPDRS Motor III scores predicted from the pattern variability data were correlated to measured scores in both groups. These results support our previous study which explained how variability analysis results for biomechanical and physiological parameters of exercise can be used to predict improvements in motor function.
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- 2016
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33. Enhanced Exercise Therapy in Parkinson's disease: A comparative effectiveness trial
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Ellen M. Walter, Elisabeth Welter, Angela L. Ridgel, Curtis Tatsuoka, Martha Sajatovic, Benjamin L. Walter, and Kari Colón-Zimmermann
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Male ,medicine.medical_specialty ,Parkinson's disease ,Supine position ,medicine.medical_treatment ,physical activity ,Physical Therapy, Sports Therapy and Rehabilitation ,Disease ,Article ,Outcome Assessment (Health Care) ,03 medical and health sciences ,Orthostatic vital signs ,0302 clinical medicine ,Physical medicine and rehabilitation ,motivation ,Psychoeducation ,Humans ,Medicine ,Orthopedics and Sports Medicine ,030212 general & internal medicine ,Cardiovascular fitness ,Physical Therapy Modalities ,Depression (differential diagnoses) ,Aged ,Aged, 80 and over ,business.industry ,Parkinson Disease ,Middle Aged ,medicine.disease ,Exercise Therapy ,3. Good health ,Blood pressure ,psychoeducation ,Physical therapy ,movement disorders ,Female ,business ,030217 neurology & neurosurgery - Abstract
Objectives Exercise can improve motor function in people with Parkinson's disease but depression reduces the motivation to participate in regular exercise. The aim of this study was to develop a novel Enhanced Exercise Therapy program that uses manual-driven guided exercise and peer-facilitated psychoeducation for individuals with Parkinson's disease and depression. Design 24 week randomized controlled design. Methods Thirty individuals were randomized to Enhanced Exercise Therapy or self-guided therapy, and evaluated at baseline, 12-weeks and at 24-weeks. Enhanced Exercise Therapy included group exercise and group psychoeducation for 12 weeks. Between 13 and 24 weeks, individuals had access to the fitness facility but group sessions were not held. Self-guided therapy included written guidelines for a self-paced exercise program and psychoeducation. Primary outcome measures included the number of exercise sessions and International Physical Activity Questionnaire score. Secondary measures included resting heart rate, supine blood pressure, estimated VO2max and incidence of orthostatic hypotension. Results Twenty four individuals completed the study (80% retention) and both groups attended similar number of exercise sessions. There were no significant changes in cardiovascular fitness measures but there was a significant increase in the amount of physical activity in the Enhanced Exercise Therapy group and a decrease in the self-guided therapy group during the post-intervention period. Conclusions Enhanced Exercise Therapy appears to promote engagement in an exercise program and more physical activity, even after group sessions were concluded in individuals with Parkinson's disease and depression.
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- 2016
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34. A Comparison of Intention Estimation Methods for Decoder Calibration in Intracortical Brain-Computer Interfaces
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Krishna V. Shenoy, Beata Jarosiewicz, Jennifer A. Sweet, Robert F. Kirsch, Jaimie M. Henderson, Chethan Pandarinath, Jad Saab, Benjamin L. Walter, Daniel R. Young, Brian Franco, Jonathan P. Miller, Leigh R. Hochberg, Christine H Blabe, A. Bolu Ajiboye, John D. Simeral, Brian A Murphy, Francis R. Willett, and William D. Memberg
- Subjects
Male ,Computer science ,Calibration (statistics) ,Movement ,0206 medical engineering ,Models, Neurological ,Biomedical Engineering ,02 engineering and technology ,Intention ,Quadriplegia ,Article ,03 medical and health sciences ,0302 clinical medicine ,Position (vector) ,Humans ,Computer Simulation ,Dimensionality reduction ,Motor Cortex ,Contrast (statistics) ,Signal Processing, Computer-Assisted ,Kalman filter ,Middle Aged ,020601 biomedical engineering ,Brain-Computer Interfaces ,Calibration ,Female ,Heuristics ,Algorithm ,030217 neurology & neurosurgery ,Decoding methods ,Smoothing ,Algorithms - Abstract
Objective : Recent reports indicate that making better assumptions about the user's intended movement can improve decoder calibration for intracortical brain–computer interfaces. Several methods now exist for estimating user intent, including an optimal feedback control model, a piecewise-linear feedback control model, ReFIT, and other heuristics. Which of these methods yields the best decoding performance? Methods : Using data from the BrainGate2 pilot clinical trial, we measured how a steady-state velocity Kalman filter decoder was affected by the choice of intention estimation method. We examined three separate components of the Kalman filter: dimensionality reduction, temporal smoothing, and output gain (speed scaling). Results : The decoder's dimensionality reduction properties were largely unaffected by the intention estimation method (the unsmoothed velocity vectors differed by $ in terms of how accurately they pointed at the target and how their speeds decreased near the target). In contrast, the smoothing and gain properties of the decoder were greatly affected ( $> \text{50}\% $ difference in average values). Surprisingly, simulation results show that these differences in gain and smoothing values were largely arbitrary, as all methods failed to optimize the gain and smoothing values to match the task parameters. Conclusion : Our results show that, gain and smoothing differences aside, current intention estimation methods yield nearly equivalent decoders and that simple models of user intent, such as a position error vector (target position minus cursor position), perform comparably to more elaborate models. Our results also highlight that current calibration methods yield arbitrary differences in gain and smoothing properties that can confound decoder comparisons.
- Published
- 2018
35. Aerodynamic Roughness Length of Fresh Snow
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Costantino Manes, Michele Guala, Michael Lehning, Benjamin L. Walter, CB Christof Gromke, and Building Physics
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Atmospheric Science ,Materials science ,Characteristic length ,business.industry ,Geometry ,Surface finish ,Snow ,Boundary layer ,Roughness length ,Optics ,Anemometer ,Surface roughness ,business ,Pressure gradient - Abstract
This study presents the results from a series of wind-tunnel experiments designed to investigate the aerodynamic roughness length z 0 of fresh snow under no-drift conditions. A two-component hot-film anemometer was employed to obtain vertical profiles of velocity statistics in a zero pressure gradient turbulent boundary layer for flow over naturally deposited snow surfaces. The roughness of these snow surfaces was measured by means of digital photography to capture characteristic length scales that can be related to z 0. Our results show that, under aerodynamically rough conditions, the mean value of the roughness length for fresh snow is $${\langle{z}_{0}\rangle= 0.24}$$ mm with a standard deviation σ(z 0)= 0.05 mm. In this study, we show that variations in z 0 are associated with variations in the roughness geometry. The roughness measurements suggest that the estimated values of z 0 are consistent with the presence of irregular roughness structures that develop during snowfalls that mimic ballistic deposition processes
- Published
- 2018
36. Efficacy and Safety of Deep Brain Stimulation in Tourette Syndrome: The International Tourette Syndrome Deep Brain Stimulation Public Database and Registry
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James F. Leckman, Sarah Elizabeth Zauber, Linda Ackermans, J. L. Houeto, Wei Hu, Zoltan Mari, Eileen M. Joyce, Fangang Meng, Terry Coyne, Michael S. Okun, Andres M. Lozano, Suketu M. Khandhar, Veerle Visser-Vandewalle, Alon Y. Mogilner, Harrison C. Walker, Erin H. Monari, Marie-Laure Welter, Michael H. Pourfar, Zinovia Kefalopoulou, Takanobu Kaido, Daniel Huys, Man Auyeung, Ludvic Zrinzo, Kelly D. Foote, Joohi Jimenez-Shahed, Aysegul Gunduz, Peter A. Silburn, Jian-Guo Zhang, Bryan T. Klassen, Jens Kuhn, Benjamin L. Walter, Elena Moro, Jill L. Ostrem, Domenico Servello, Daniel Martinez-Ramirez, Luc Mallet, Kyle Rizer, Barbara Changizi, Marwan Hariz, Carine Karachi, Yasin Temel, Mauro Porta, William S. Anderson, Juan Carlos Baldermann, Lauren E. Schrock, Robert E. Gross, Wissam Deeb, Thomas Foltynie, Irene A. Malaty, MUMC+: MA Med Staf Spec Neurochirurgie (9), RS: MHeNs - R3 - Neuroscience, and Neurochirurgie
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0301 basic medicine ,Male ,Pediatrics ,Neurology ,Databases, Factual ,Deep Brain Stimulation ,medicine.medical_treatment ,International Cooperation ,Tourette syndrome ,Severity of Illness Index ,RECOMMENDATIONS ,Cohort Studies ,ddc:616.89 ,0302 clinical medicine ,Tourette Syndrome/therapy ,Thalamus ,PARKINSONS-DISEASE ,Medicine ,Single-Blind Method ,Registries ,Young adult ,Globus Pallidus/physiology ,Original Investigation ,Middle Aged ,surgical procedures, operative ,Treatment Outcome ,Female ,therapeutics ,Cohort study ,Thalamus/physiology ,Adult ,medicine.medical_specialty ,Deep brain stimulation ,Adolescent ,MEDLINE ,Globus Pallidus ,behavioral disciplines and activities ,03 medical and health sciences ,Databases ,Young Adult ,Deep Brain Stimulation/methods ,Severity of illness ,Factual/statistics & numerical data ,Humans ,ddc:613 ,business.industry ,medicine.disease ,nervous system diseases ,Institutional repository ,030104 developmental biology ,nervous system ,Neurology (clinical) ,business ,030217 neurology & neurosurgery ,Tourette Syndrome - Abstract
IMPORTANCE Collective evidence has strongly suggested that deep brain stimulation (DBS) is a promising therapy for Tourette syndrome. OBJECTIVE To assess the efficacy and safety of DBS in a multinational cohort of patients with Tourette syndrome. DESIGN, SETTING, AND PARTICIPANTS The prospective International Deep Brain Stimulation Database and Registry included 185 patients with medically refractory Tourette syndrome who underwent DBS implantation from January 1, 2012, to December 31, 2016, at 31 institutions in 10 countries worldwide. EXPOSURES Patients with medically refractory symptoms received DBS implantation in the centromedian thalamic region (93 of 163 [57.1%]), the anterior globus pallidus internus (41 of 163 [25.2%]), the posterior globus pallidus internus (25 of 163 [15.3%]), and the anterior limb of the internal capsule (4 of 163 [2.5%]). MAINOUTCOMES AND MEASURES Scores on the Yale Global Tic Severity Scale and adverse events. RESULTS The International Deep Brain Stimulation Database and Registry enrolled 185 patients (of 171 with available data, 37 females and 134 males; mean [SD] age at surgery, 29.1 [10.8] years [range, 13-58 years]). Symptoms of obsessive-compulsive disorder were present in 97 of 151 patients (64.2%) and 32 of 148 (21.6%) had a history of self-injurious behavior. The mean (SD) total Yale Global Tic Severity Scale score improved from 75.01 (18.36) at baseline to 41.19 (20.00) at 1 year after DBS implantation (P
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- 2018
37. A randomized trial of individual versus group-format exercise and self-management in individuals with Parkinson’s disease and comorbid depression
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Ellen M. Walter, Riane K. Ramsey, Angela L. Ridgel, Elisabeth Welter, Curtis Tatsuoka, Steven A. Gunzler, Christina M. Whitney, Martha Sajatovic, Benjamin L. Walter, and Kari Colón-Zimmermann
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medicine.medical_specialty ,medicine.medical_treatment ,Population ,physical activity ,Medicine (miscellaneous) ,community-based research ,rehabilitation ,law.invention ,03 medical and health sciences ,0302 clinical medicine ,Physical medicine and rehabilitation ,Quality of life ,Randomized controlled trial ,law ,Rating scale ,medicine ,Apathy ,030212 general & internal medicine ,education ,Pharmacology, Toxicology and Pharmaceutics (miscellaneous) ,Depression (differential diagnoses) ,Original Research ,education.field_of_study ,Rehabilitation ,business.industry ,Health Policy ,3. Good health ,Patient Preference and Adherence ,Physical therapy ,Anxiety ,medicine.symptom ,business ,mental health ,030217 neurology & neurosurgery ,Social Sciences (miscellaneous) - Abstract
Martha Sajatovic,1,2 Angela L Ridgel,3 Ellen M Walter,1,4 Curtis M Tatsuoka,1,2 Kari Colón-Zimmermann,2 Riane K Ramsey,2 Elisabeth Welter,2 Steven A Gunzler,1,4 Christina M Whitney,1,4 Benjamin L Walter1,4 1Department of Neurology, Case Western Reserve University School of Medicine, 2Neurological and Behavioral Outcomes Center, University Hospitals Cleveland Medical Center, Cleveland, 3Department of Exercise Physiology, Kent State University, Kent, 4Movement Disorders Center, University Hospitals Cleveland Medical Center, Cleveland, OH, USA Background: Depression is common in people with Parkinson’s disease (PD), and exercise is known to improve depression and PD. However, lack of motivation and low self-efficacy can make exercise difficult for people with PD and comorbid depression (PD-Dep). A combined group exercise and chronic disease self-management (CDSM) program may improve the likelihood that individuals will engage in exercise and will show a reduction in depression symptoms. The purpose of this study was to compare changes in depression in PD-Dep between individual versus group exercise plus CDSM and to examine participant adherence and perception of the interventions.Methods: Participants (N=30) were randomized to either Enhanced EXerCisE thErapy for PD (EXCEED; group CDSM and exercise) or self-guided CDSM plus exercise. Outcomes were change in depression assessed with the Montgomery–Asberg Depression Rating Scale (MADRS), cognition, apathy, anxiety, sleep, quality of life, motor function, self-efficacy, and patient satisfaction.Results: Both groups showed significant improvement in MADRS (P
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- 2017
38. Tourette syndrome deep brain stimulation: A review and updated recommendations
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Douglas W. Woods, Suketu M. Khandhar, Zoltan Mari, Mauro Porta, Dominico Servello, James F. Leckman, Benjamin L. Walter, Harrison C. Walker, Takanobu Kaido, Linda Ackermans, Robert E. Gross, Yves Agid, Lauren E. Schrock, Man Auyeung, Jorge L. Juncos, Thomas Foltynie, Veerle Visser-Vandewalle, Joseph A. Neimat, Peter A. Silburn, Jens Kuhn, Yasin Temel, Alon Y. Mogilner, Barbara Changizi, Rodolfo Savica, Bryan T. Klassen, Jonathan W. Mink, Marie L. Welter, Kelly D. Foote, Joohi Shahed-Jimenez, Jian-Guo Zhang, Michael S. Okun, Michael H. Pourfar, Andre G. Machado, Wei Hu, and Andres M. Lozano
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education.field_of_study ,medicine.medical_specialty ,Pediatrics ,Movement disorders ,Deep brain stimulation ,Tics ,medicine.medical_treatment ,Population ,medicine.disease ,Institutional review board ,Tourette syndrome ,nervous system diseases ,Neurology ,Malingering ,medicine ,Physical therapy ,Psychogenic disease ,Neurology (clinical) ,medicine.symptom ,education ,Psychology - Abstract
Deep brain stimulation (DBS) may improve disabling tics in severely affected medication and behaviorally resistant Tourette syndrome (TS). Here we review all reported cases of TS DBS and provide updated recommendations for selection, assessment, and management of potential TS DBS cases based on the literature and implantation experience. Candidates should have a Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM V) diagnosis of TS with severe motor and vocal tics, which despite exhaustive medical and behavioral treatment trials result in significant impairment. Deep brain stimulation should be offered to patients only by experienced DBS centers after evaluation by a multidisciplinary team. Rigorous preoperative and postoperative outcome measures of tics and associated comorbidities should be used. Tics and comorbid neuropsychiatric conditions should be optimally treated per current expert standards, and tics should be the major cause of disability. Psychogenic tics, embellishment, and malingering should be recognized and addressed. We have removed the previously suggested 25-year-old age limit, with the specification that a multidisciplinary team approach for screening is employed. A local ethics committee or institutional review board should be consulted for consideration of cases involving persons younger than 18 years of age, as well as in cases with urgent indications. Tourette syndrome patients represent a unique and complex population, and studies reveal a higher risk for post-DBS complications. Successes and failures have been reported for multiple brain targets; however, the optimal surgical approach remains unknown. Tourette syndrome DBS, though still evolving, is a promising approach for a subset of medication refractory and severely affected patients.
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- 2014
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39. Experimental assessment of Owen's second hypothesis on surface shear stress induced by a fluid during sediment saltation
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Stefan Horender, Michael Lehning, Christian Voegeli, and Benjamin L. Walter
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Physics::Fluid Dynamics ,Geophysics ,Flux (metallurgy) ,Flow velocity ,Particle mass ,Saltation (geology) ,Stress induced ,General Earth and Planetary Sciences ,Geotechnical engineering ,Mechanics ,Surface shear ,Geology ,Wind tunnel - Abstract
A widely used, yet thus far unproven, fluid dynamical hypothesis originally presented by P. R. Owen 50years ago, states that the surface shear stress induced by a fluid on the ground during equilibrium sediment saltation is constant and independent of the magnitude of the fluid velocity and consequently the particle mass flux. This hypothesis is one of the key elements in almost all current model descriptions of sediment erosion. We measured the surface shear stress in a drifting-sand wind tunnel and found Owen's hypothesis being merely an approximation of the real situation. A significant decrease of the fluid stress with increasing wind velocities was measured for low to intermediate particle mass fluxes. For high particle mass fluxes, Owen's hypothesis essentially holds, although a slight increase of the fluid stress was measured.
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- 2014
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40. Fiber tractography of the axonal pathways linking the basal ganglia and cerebellum in Parkinson disease: implications for targeting in deep brain stimulation
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Ashutosh Chaturvedi, Jonathan P. Miller, Benjamin L. Walter, Kabilar Gunalan, Cameron C. McIntyre, and Jennifer A. Sweet
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Male ,Cerebellum ,Pathology ,medicine.medical_specialty ,Deep brain stimulation ,Deep Brain Stimulation ,medicine.medical_treatment ,Dentatothalamic tract ,Stimulation ,Basal Ganglia ,Article ,White matter ,Cerebellar hemisphere ,Neural Pathways ,Basal ganglia ,medicine ,Humans ,Aged ,business.industry ,Parkinson Disease ,Middle Aged ,Axons ,Diffusion Tensor Imaging ,Treatment Outcome ,medicine.anatomical_structure ,Female ,business ,Neuroscience ,Diffusion MRI - Abstract
Object Stimulation of white matter pathways near targeted structures may contribute to therapeutic effects of deep brain stimulation (DBS) for patients with Parkinson disease (PD). Two tracts linking the basal ganglia and cerebellum have been described in primates: the subthalamopontocerebellar tract (SPCT) and the dentatothalamic tract (DTT). The authors used fiber tractography to evaluate white matter tracts that connect the cerebellum to the region of the basal ganglia in patients with PD who were candidates for DBS. Methods Fourteen patients with advanced PD underwent 3-T MRI, including 30-directional diffusion-weighted imaging sequences. Diffusion tensor tractography was performed using 2 regions of interest: ipsilateral subthalamic and red nuclei, and contralateral cerebellar hemisphere. Nine patients underwent subthalamic DBS, and the course of each tract was observed relative to the location of the most effective stimulation contact and the volume of tissue activated. Results In all patients 2 distinct tracts were identified that corresponded closely to the described anatomical features of the SPCT and DTT, respectively. The mean overall distance from the active contact to the DTT was 2.18 ± 0.35 mm, and the mean proportional distance relative to the volume of tissue activated was 1.35 ± 0.48. There was a nonsignificant trend toward better postoperative tremor control in patients with electrodes closer to the DTT. Conclusions The SPCT and the DTT may be related to the expression of symptoms in PD, and this may have implications for DBS targeting. The use of tractography to identify the DTT might assist with DBS targeting in the future.
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- 2014
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41. Measurements of the pore-scale water flow through snow using Fluorescent Particle Tracking Velocimetry
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Benjamin L. Walter, CB Christof Gromke, Stefan Horender, and Michael Lehning
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Hydrology ,Materials science ,Water flow ,Capillary action ,Maximum flow problem ,Mechanics ,Velocimetry ,Snow ,Flow measurement ,Physics::Geophysics ,Physics::Fluid Dynamics ,Flow (mathematics) ,Seeding ,Water Science and Technology - Abstract
[1] Fluorescent Particle Tracking Velocimetry (FPTV) measurements of the pore-scale water flow through the pore space of a wet-snow sample are presented to demonstrate the applicability of this measurement technique for snow. For the experiments, ice-cooled water seeded with micron sized fluorescent tracer particles is either sprinkled on top of a snow sample to investigate saturated and unsaturated gravity-driven flow or supplied from a reservoir below the snow sample to generate upward flow driven by capillary forces. The snow sample is illuminated with a laser light sheet and the fluorescent light of the particles transported with the water in the pore space is recorded with a high-speed camera equipped with an optical filter. Tracking algorithms are applied to the images to obtain flow paths and flow velocities. A flow loop found in a pore space for the case of saturated gravity flow together with the tortuosity of the particle trajectories indicate the three-dimensionality of the water flow in wet snow. The average vertical flow velocities in the pore spaces were 11.2 mm s � 1 for the downward saturated gravity flow and 9.6 mm s � 1 for the upward flow that is driven by capillary forces for the limited cases presented as examples of the measurement technique. In the case of unsaturated gravity-driven flow, the average and the maximum flow velocities were found to be 30 times smaller than for the saturated gravity flow. Velocity histograms show that the fraction of the total water flowing against the main flow direction was about 3–5%, and that the horizontal velocities average to zero for both the saturated gravity-driven and the capillary flow.
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- 2013
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42. Web-Interface-Driven Development for Neuro3D, a Clinical Data Capture and Decision Support System for Deep Brain Stimulation
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Benjamin L. Walter, Guo-Qiang Zhang, Shiqiang Tao, and Sisi Gu
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0301 basic medicine ,Decision support system ,business.industry ,Computer science ,Automatic identification and data capture ,Clinical decision support system ,Data science ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Workflow ,Data quality ,Informatics ,Business logic ,business ,030217 neurology & neurosurgery ,Agile software development - Abstract
Parkinson’s Disease is a common chronic neurological motor system disorder that affects more than 10 million people worldwide with no known cure. With Deep Brain Stimulation (DBS) emerging as one of the main treatments for Parkinson’s Disease, the effective capture, retrieval, and analysis of data generated from DBS are important informatics challenges. To address these challenges, this paper presents the design and implementation of Neuro3D, a web-interfaced system for DBS data capture and management in the clinical setting. Neuro3D provides: (1) data capture interfaces with multiple data entry assistances and validations to improve both the data entry efficiency and the data quality; (2) intuitive data organization that mirrors the workflow of clinical operations; and (3) a novel data exploration as a basis for clinical decision support. Neuro3D accomplishes these utilizing an agile development strategy called Web-Interface-Driven Development (WIDD) to optimize the communication between software developers and domain experts. 36 distinct data forms consisting of 1109 discrete data elements are captured and managed in Neuro3D. Pilot deployment of Neuro3D in the Movement Disorders Center of the University Hospitals Neurological Institute in Cleveland captured clinical data for 236 patients, in a comprehensive and research-ready fashion beyond the scope of current EMR. Neuro3D fills an important void in terms of tools for capturing large-scale clinical neurology data to improve care and outcome for patients with Parkinson’s disease.
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- 2016
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43. Standard guidelines for publication of deep brain stimulation studies in Parkinson's disease (Guide4DBS-PD)
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Roy A.E. Bakay, Kelly E. Lyons, Roger Kurlan, Mark Hallett, Anthony E. Lang, Jerrold L. Vitek, Alim-Louis Benabid, Benjamin L. Walter, Guenther Deuschl, Ali R. Rezai, and Joseph J. Pancrazio
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medicine.medical_specialty ,Deep brain stimulation ,Movement disorders ,Parkinson's disease ,business.industry ,medicine.medical_treatment ,Disease ,medicine.disease ,Checklist ,Central nervous system disease ,Degenerative disease ,Neurology ,medicine ,Neurology (clinical) ,medicine.symptom ,Intensive care medicine ,business ,Neuroscience - Abstract
While the use of deep brain stimulation (DBS) for the treatment of neurological disorders has risen substantially over the last decade, it is often difficult to compare the results from different studies due to the lack of consistent reporting of key study parameters. We present guidelines to standardize the reporting of clinical studies of DBS for Parkinson's disease (PD). These guidelines provide a minimal set of required data elements to facilitate the interpretation and comparison of results across published clinical studies. The guidelines, summarized in the format of a checklist, may also have utility in the planning of clinical studies of DBS for PD as well as other neurological and psychiatric disorders.
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- 2010
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44. Somatotopic organization in the internal segment of the globus pallidus in Parkinson's disease
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Roy A.E. Bakay, Benjamin L. Walter, Gaurav Mavinkurve, Mahlon R. DeLong, Gary S. Russo, Kenneth B. Baker, Jerrold L. Vitek, and John Y K Lee
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Deep brain stimulation ,Stereotactic surgery ,Parkinson's disease ,Deep Brain Stimulation ,medicine.medical_treatment ,Sensation ,Globus Pallidus ,Article ,Functional Laterality ,Developmental Neuroscience ,Basal ganglia ,medicine ,Humans ,Pallidotomy ,Kinesthesis ,Neurons ,Brain Mapping ,Parkinson Disease ,Anatomy ,Proprioception ,medicine.disease ,Magnetic Resonance Imaging ,Globus pallidus ,Neurology ,Receptive field ,Multivariate Analysis ,Body region ,Tomography, X-Ray Computed ,Psychology ,Neuroscience - Abstract
Ablation or deep brain stimulation in the internal segment of the globus pallidus (GPi) is an effective therapy for the treatment of Parkinson's disease (PD). Yet many patients receive only partial benefit, including varying levels of improvement across different body regions, which may relate to a differential effect of GPi surgery on the different body regions. Unfortunately, our understanding of the somatotopic organization of human GPi is based on a small number of studies with limited sample sizes, including several based upon only a single recording track or plane. To fully address the three-dimensional somatotopic organization of GPi, we examined the receptive field properties of pallidal neurons in a large cohort of patients undergoing stereotactic surgery. The response of neurons to active and passive movements of the limbs and orofacial structures was determined, using a minimum of three tracks across at least two medial-lateral planes. Neurons (3183) were evaluated from 299 patients, of which 1972 (62%) were modulated by sensorimotor manipulation. Of these, 1767 responded to a single, contralateral body region, with the remaining 205 responding to multiple and/or ipsilateral body regions. Leg-related neurons were found dorsal, medial and anterior to arm-related neurons, while arm-related neurons were dorsal and lateral to orofacial-related neurons. This study provides a more detailed map of individual body regions as well as specific joints within each region and provides a potential explanation for the differential effect of lesions or DBS of the GPi on different body parts in patients undergoing surgical treatment of movement disorders.
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- 2010
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45. Signal processing methods for reducing artifacts in microelectrode brain recordings caused by functional electrical stimulation
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William D. Memberg, Jennifer A. Sweet, Jonathan P. Miller, Francis R. Willett, Leigh R. Hochberg, Abidemi B. Ajiboye, Daniel R. Young, Brian A Murphy, Robert F. Kirsch, and Benjamin L. Walter
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Computer science ,Deep Brain Stimulation ,Noise reduction ,0206 medical engineering ,Biomedical Engineering ,Pilot Projects ,Stimulation ,02 engineering and technology ,Thoracic Vertebrae ,Article ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,medicine ,Humans ,Functional electrical stimulation ,Muscle, Skeletal ,Spinal Cord Injuries ,Brain–computer interface ,Artifact (error) ,Signal processing ,Motor Cortex ,Signal Processing, Computer-Assisted ,020601 biomedical engineering ,Electrodes, Implanted ,Microelectrode ,medicine.anatomical_structure ,Brain-Computer Interfaces ,Arm ,Artifacts ,Microelectrodes ,030217 neurology & neurosurgery ,Biomedical engineering ,Motor cortex - Abstract
Objective Functional electrical stimulation (FES) is a promising technology for restoring movement to paralyzed limbs. Intracortical brain-computer interfaces (iBCIs) have enabled intuitive control over virtual and robotic movements, and more recently over upper extremity FES neuroprostheses. However, electrical stimulation of muscles creates artifacts in intracortical microelectrode recordings that could degrade iBCI performance. Here, we investigate methods for reducing the cortically recorded artifacts that result from peripheral electrical stimulation. Approach One participant in the BrainGate2 pilot clinical trial had two intracortical microelectrode arrays placed in the motor cortex, and thirty-six stimulating intramuscular electrodes placed in the muscles of the contralateral limb. We characterized intracortically recorded electrical artifacts during both intramuscular and surface stimulation. We compared the performance of three artifact reduction methods: blanking, common average reference (CAR) and linear regression reference (LRR), which creates channel-specific reference signals, composed of weighted sums of other channels. Main results Electrical artifacts resulting from surface stimulation were 175 × larger than baseline neural recordings (which were 110 µV peak-to-peak), while intramuscular stimulation artifacts were only 4 × larger. The artifact waveforms were highly consistent across electrodes within each array. Application of LRR reduced artifact magnitudes to less than 10 µV and largely preserved the original neural feature values used for decoding. Unmitigated stimulation artifacts decreased iBCI decoding performance, but performance was almost completely recovered using LRR, which outperformed CAR and blanking and extracted useful neural information during stimulation artifact periods. Significance The LRR method was effective at reducing electrical artifacts resulting from both intramuscular and surface FES, and almost completely restored iBCI decoding performance (>90% recovery for surface stimulation and full recovery for intramuscular stimulation). The results demonstrate that FES-induced artifacts can be easily mitigated in FES + iBCI systems by using LRR for artifact reduction, and suggest that the LRR method may also be useful in other noise reduction applications.
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- 2018
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46. Rapid calibration of an intracortical brain–computer interface for people with tetraplegia
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Robert F. Kirsch, Brian Franco, Krishna V. Shenoy, Daniel Milstein, Jad Saab, Chethan Pandarinath, Jaimie M. Henderson, Leigh R. Hochberg, Jonathan P. Miller, Beata Jarosiewicz, Benjamin L. Walter, Anish A. Sarma, Francis R. Willett, David M. Brandman, Christine H Blabe, Carlos E. Vargas-Irwin, Brian A Murphy, Tommy Hosman, Emad N. Eskandar, John D. Simeral, Sydney S. Cash, Matthew T. Harrison, John G. Ciancibello, Michael C. Burkhart, Benjamin E. Shanahan, Jessica N. Kelemen, Sergey D. Stavisky, Daniel R. Young, Jennifer A. Sweet, and A Bolu Ajiboye
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Adult ,Male ,0301 basic medicine ,Time Factors ,Computer science ,Clinical Sciences ,Real-time computing ,Biomedical Engineering ,Initialization ,Bioengineering ,Quadriplegia ,Article ,brain-computer interfaces ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Robustness (computer science) ,Calibration ,medicine ,Humans ,Tetraplegia ,Brain–computer interface ,Assistive Technology ,Neurosciences ,Motor Cortex ,Kalman filter ,Middle Aged ,medicine.disease ,neural decoding ,discriminative Kalman filter ,Implantable Neurostimulators ,030104 developmental biology ,Brain-Computer Interfaces ,Female ,Kalman filtering ,Gaussian process regression ,030217 neurology & neurosurgery ,Decoding methods ,Neural decoding - Abstract
OBJECTIVE: Brain Computer Interfaces (BCIs) can enable individuals with tetraplegia to communicate and control external devices. Though much progress has been made in improving the speed and robustness of neural control provided by intracortical BCIs, little research has been devoted to minimizing the amount of time spent on decoder calibration. APPROACH: We investigated the amount of time users needed to calibrate decoders and achieve performance saturation using two markedly different decoding algorithms: the steady-state Kalman filter, and a novel technique using Gaussian process regression (GP-DKF). MAIN RESULTS: Three people with tetraplegia gained rapid closed-loop neural cursor control and peak, plateaued decoder performance within three minutes of initializing calibration. We also show that a BCI-naïve user (T5) was able to rapidly attain closed-loop neural cursor control with the GP-DKF using self-selected movement imagery on his first-ever day of closed-loop BCI use, acquiring a target 37 seconds after initiating calibration. SIGNIFICANCE: These results demonstrate the potential for an intracortical BCI to be used immediately after deployment by people with paralysis, without the need for user learning or extensive system calibration.
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- 2018
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47. Automated 3-Dimensional Brain Atlas Fitting to Microelectrode Recordings from Deep Brain Stimulation Surgeries
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Christopher R. Butson, Jerrold L. Vitek, Benjamin L. Walter, Scott E. Cooper, J. Luis Lujan, Cameron C. McIntyre, and Angela M. Noecker
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Brain Mapping ,Deep brain stimulation ,Databases, Factual ,Extramural ,business.industry ,Deep Brain Stimulation ,medicine.medical_treatment ,Brain atlas ,Brain ,Brain mapping ,Electrodes, Implanted ,Stereotaxic Techniques ,Microelectrode ,Imaging, Three-Dimensional ,Stereotaxic technique ,Clinical Study ,medicine ,Humans ,Surgery ,Neurology (clinical) ,business ,Neuroscience ,Stereotactic neurosurgery ,Software ,Retrospective Studies - Abstract
Objective: Deep brain stimulation (DBS) surgeries commonly rely on brain atlases and microelectrode recordings (MER) to help identify the target location for electrode implantation. We present an automated method for optimally fitting a 3-dimensional brain atlas to intraoperative MER and predicting a target DBS electrode location in stereotactic coordinates for the patient. Methods: We retrospectively fit a 3-dimensional brain atlas to MER points from 10 DBS surgeries targeting the subthalamic nucleus (STN). We used a constrained optimization algorithm to maximize the MER points correctly fitted (i.e., contained) within the appropriate atlas nuclei. We compared our optimization approach to conventional anterior commissure-posterior commissure (AC/PC) scaling, and to manual fits performed by four experts. A theoretical DBS electrode target location in the dorsal STN was customized to each patient as part of the fitting process and compared to the location of the clinically defined therapeutic stimulation contact. Results: The human expert and computer optimization fits achieved significantly better fits than the AC/PC scaling (80, 81, and 41% of correctly fitted MER, respectively). However, the optimization fits were performed in less time than the expert fits and converged to a single solution for each patient, eliminating interexpert variance. Conclusions and Significance: DBS therapeutic outcomes are directly related to electrode implantation accuracy. Our automated fitting techniques may aid in the surgical decision-making process by optimally integrating brain atlas and intraoperative neurophysiological data to provide a visual guide for target identification.
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- 2009
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48. Deep brain stimulation activation volumes and their association with neurophysiological mapping and therapeutic outcomes
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Cameron C. McIntyre, Christopher B. Maks, Jerrold L. Vitek, Christopher R. Butson, and Benjamin L. Walter
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Deep brain stimulation ,Deep Brain Stimulation ,medicine.medical_treatment ,Context (language use) ,Synaptic Transmission ,Brain mapping ,Article ,Imaging, Three-Dimensional ,Thalamus ,Neuroimaging ,Subthalamic Nucleus ,Image Processing, Computer-Assisted ,medicine ,Humans ,Dominance, Cerebral ,Neurostimulation ,Neurologic Examination ,Neurons ,Brain Mapping ,Brain atlas ,Parkinson Disease ,Magnetic Resonance Imaging ,Electrodes, Implanted ,Substantia Nigra ,Psychiatry and Mental health ,Subthalamic nucleus ,Diffusion Magnetic Resonance Imaging ,Treatment Outcome ,medicine.anatomical_structure ,nervous system ,Surgery ,Neurology (clinical) ,Nerve Net ,Tomography, X-Ray Computed ,Psychology ,Neuroscience ,Neuroanatomy - Abstract
Objective: Despite the clinical success of deep brain stimulation (DBS) for the treatment of Parkinson’s disease (PD), little is known about the electrical spread of the stimulation. The primary goal of this study was to integrate neuroimaging, neurophysiology and neurostimulation data sets from 10 patients with PD, unilaterally implanted with subthalamic nucleus (STN) DBS electrodes, to identify the theoretical volume of tissue activated (VTA) by clinically defined therapeutic stimulation parameters. Methods: Each patient specific model was created with a series of five steps: (1) definition of the neurosurgical stereotactic coordinate system within the context of preoperative imaging data; (2) entry of intraoperative microelectrode recording locations from neurophysiologically defined thalamic, subthalamic and substantia nigra neurons into the context of the imaging data; (3) fitting a three dimensional brain atlas to the neuroanatomy and neurophysiology of the patient; (4) positioning the DBS electrode in the documented stereotactic location, verified by postoperative imaging data; and (5) calculation of the VTA using a diffusion tensor based finite element neurostimulation model. Results: The patient specific models show that therapeutic benefit was achieved with direct stimulation of a wide range of anatomical structures in the subthalamic region. Interestingly, of the five patients exhibiting a greater than 40% improvement in their Unified PD Rating Scale (UPDRS), all but one had the majority of their VTA outside the atlas defined borders of the STN. Furthermore, of the five patients with less than 40% UPDRS improvement, all but one had the majority of their VTA inside the STN. Conclusions: Our results are consistent with previous studies suggesting that therapeutic benefit is associated with electrode contacts near the dorsal border of the STN, and provide quantitative estimates of the electrical spread of the stimulation in a clinically relevant context.
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- 2008
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49. CLINICAL PROBLEM SOLVING
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Milind Deogaonkar, Benjamin L. Walter, Nicholas M. Boulis, and Philip A. Starr
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Male ,medicine.medical_specialty ,business.industry ,Deep Brain Stimulation ,Medical screening ,Parkinson Disease ,Radiosurgery ,Surgery ,Problem solving - finding ,Radiography ,Microelectrode recording ,Subthalamic Nucleus ,medicine ,Humans ,Neurology (clinical) ,Artificial intelligence ,business ,Problem Solving ,Aged - Published
- 2007
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50. Tourette Syndrome Deep Brain Stimulation: A Review and Updated Recommendations
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Lauren E, Schrock, Jonathan W, Mink, Douglas W, Woods, Mauro, Porta, Dominico, Servello, Veerle, Visser-Vandewalle, Peter A, Silburn, Thomas, Foltynie, Harrison C, Walker, Joohi, Shahed-Jimenez, Rodolfo, Savica, Bryan T, Klassen, Andre G, Machado, Kelly D, Foote, Jian-Guo, Zhang, Wei, Hu, Linda, Ackermans, Yasin, Temel, Zoltan, Mari, Barbara K, Changizi, Andres, Lozano, M, Auyeung, Takanobu, Kaido, Yves, Agid, Marie L, Welter, Suketu M, Khandhar, Alon Y, Mogilner, Michael H, Pourfar, Benjamin L, Walter, Jorge L, Juncos, Robert E, Gross, Jens, Kuhn, James F, Leckman, Joseph A, Neimat, Michael S, Okun, Neurochirurgie, MUMC+: MA Med Staf Spec Neurochirurgie (9), and RS: MHeNs - R3 - Neuroscience
- Subjects
Tourette syndrome ,Humans ,DBS ,Guidelines as Topic ,guidelines ,deep brain stimulation - Abstract
Deep brain stimulation (DBS) may improve disabling tics in severely affected medication and behaviorally resistant Tourette syndrome (TS). Here we review all reported cases of TS DBS and provide updated recommendations for selection, assessment, and management of potential TS DBS cases based on the literature and implantation experience. Candidates should have a Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM V) diagnosis of TS with severe motor and vocal tics, which despite exhaustive medical and behavioral treatment trials result in significant impairment. Deep brain stimulation should be offered to patients only by experienced DBS centers after evaluation by a multidisciplinary team. Rigorous preoperative and postoperative outcome measures of tics and associated comorbidities should be used. Tics and comorbid neuropsychiatric conditions should be optimally treated per current expert standards, and tics should be the major cause of disability. Psychogenic tics, embellishment, and malingering should be recognized and addressed. We have removed the previously suggested 25-year-old age limit, with the specification that a multidisciplinary team approach for screening is employed. A local ethics committee or institutional review board should be consulted for consideration of cases involving persons younger than 18 years of age, as well as in cases with urgent indications. Tourette syndrome patients represent a unique and complex population, and studies reveal a higher risk for post-DBS complications. Successes and failures have been reported for multiple brain targets; however, the optimal surgical approach remains unknown. Tourette syndrome DBS, though still evolving, is a promising approach for a subset of medication refractory and severely affected patients.
- Published
- 2015
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