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Ribeiro M, Andreis FR, Jabban L, Nielsen TGNDS, Smirnov SV, Lutteroth C, Proulx MJ, Rocha PRF, Metcalfe B. Ex-vivo systems for neuromodulation: A comparison of ex-vivo and in-vivo large animal nerve electrophysiology. J Neurosci Methods 2024; 406:110116. [PMID: 38548122 DOI: 10.1016/j.jneumeth.2024.110116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 03/05/2024] [Accepted: 03/21/2024] [Indexed: 04/04/2024]
Abstract
BACKGROUND Little research exists on extending ex-vivo systems to large animal nerves, and to the best of our knowledge, there has yet to be a study comparing these against in-vivo data. This paper details the first ex-vivo system for large animal peripheral nerves to be compared with in-vivo results. NEW METHOD Detailed ex-vivo and in-vivo closed-loop neuromodulation experiments were conducted on pig ulnar nerves. Temperatures from 20 °C to 37 °C were evaluated for the ex-vivo system. The data were analysed in the time and velocity domains, and a regression analysis established how evoked compound action potential amplitude and modal conduction velocity (CV) varied with temperature and time after explantation. MAIN RESULTS Pig ulnar nerves were sustained ex-vivo up to 5 h post-explantation. CV distributions of ex-vivo and in-vivo data were compared, showing closer correspondence at 37 °C. Regression analysis results also demonstrated that modal CV and time since explantation were negatively correlated, whereas modal CV and temperature were positively correlated. COMPARISON WITH EXISTING METHODS Previous ex-vivo systems were primarily aimed at small animal nerves, and we are not aware of an ex-vivo system to be directly compared with in-vivo data. This new approach provides a route to understand how ex-vivo systems for large animal nerves can be developed and compared with in-vivo data. CONCLUSION The proposed ex-vivo system results were compared with those seen in-vivo, providing new insights into large animal nerve activity post-explantation. Such a system is crucial for complementing in-vivo experiments, maximising collected experimental data, and accelerating neural interface development.
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Affiliation(s)
- Mafalda Ribeiro
- Centre for Accountable, Responsible, and Transparent AI (ART-AI), Department of Computer Science, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom; Department of Electronic & Electrical Engineering, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom.
| | - Felipe R Andreis
- Centre for Neuroplasticity and Pain (CNAP), Department of Health Science and Technology, Aalborg University, Selma Lagerløfs Vej 249, 9260, Gistrup, Denmark
| | - Leen Jabban
- Department of Electronic & Electrical Engineering, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom
| | - Thomas G N dS Nielsen
- Centre for Neuroplasticity and Pain (CNAP), Department of Health Science and Technology, Aalborg University, Selma Lagerløfs Vej 249, 9260, Gistrup, Denmark
| | - Sergey V Smirnov
- Department of Life Sciences, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom
| | - Christof Lutteroth
- Centre for Accountable, Responsible, and Transparent AI (ART-AI), Department of Computer Science, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom; Department of Computer Science, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom
| | - Michael J Proulx
- Centre for Accountable, Responsible, and Transparent AI (ART-AI), Department of Computer Science, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom; Department of Psychology, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom
| | - Paulo R F Rocha
- Centre for Functional Ecology - Science for People & the Planet (CFE), TERRA Associate Laboratory, Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456, Coimbra, Portugal
| | - Benjamin Metcalfe
- Centre for Accountable, Responsible, and Transparent AI (ART-AI), Department of Computer Science, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom; The Bath Institute for the Augmented Human, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom.
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Woods JE, Singer AL, Alrashdan F, Tan W, Tan C, Sheth SA, Sheth SA, Robinson JT. Miniature battery-free epidural cortical stimulators. SCIENCE ADVANCES 2024; 10:eadn0858. [PMID: 38608028 PMCID: PMC11014439 DOI: 10.1126/sciadv.adn0858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 03/11/2024] [Indexed: 04/14/2024]
Abstract
Miniaturized neuromodulation systems could improve the safety and reduce the invasiveness of bioelectronic neuromodulation. However, as implantable bioelectronic devices are made smaller, it becomes difficult to store enough power for long-term operation in batteries. Here, we present a battery-free epidural cortical stimulator that is only 9 millimeters in width yet can safely receive enough wireless power using magnetoelectric antennas to deliver 14.5-volt stimulation bursts, which enables it to stimulate cortical activity on-demand through the dura. The device has digitally programmable stimulation output and centimeter-scale alignment tolerances when powered by an external transmitter. We demonstrate that this device has enough power and reliability for real-world operation by showing acute motor cortex activation in human patients and reliable chronic motor cortex activation for 30 days in a porcine model. This platform opens the possibility of simple surgical procedures for precise neuromodulation.
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Affiliation(s)
- Joshua E. Woods
- Department of Electrical and Computer Engineering, Rice University, 6100 Main St, Houston, TX 77005, USA
| | - Amanda L. Singer
- Motif Neurotech, 2450 Holcombe Blvd, Houston, TX 77021, USA
- Applied Physics Program, Rice University, 6100 Main St, Houston, TX 77005, USA
| | - Fatima Alrashdan
- Department of Electrical and Computer Engineering, Rice University, 6100 Main St, Houston, TX 77005, USA
| | - Wendy Tan
- Department of Electrical and Computer Engineering, Rice University, 6100 Main St, Houston, TX 77005, USA
| | - Chunfeng Tan
- Department of Neurology, UTHealth McGovern Medical School, 6431 Fannin St, Houston, TX 77030, USA
| | - Sunil A. Sheth
- Department of Neurology, UTHealth McGovern Medical School, 6431 Fannin St, Houston, TX 77030, USA
| | - Sameer A. Sheth
- Department of Neurosurgery, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX 77030, USA
| | - Jacob T. Robinson
- Department of Electrical and Computer Engineering, Rice University, 6100 Main St, Houston, TX 77005, USA
- Motif Neurotech, 2450 Holcombe Blvd, Houston, TX 77021, USA
- Applied Physics Program, Rice University, 6100 Main St, Houston, TX 77005, USA
- Department of Bioengineering, Rice University, 6100 Main St, Houston, TX 77005, USA
- Department of Neuroscience, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX 77030, USA
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Bhowmick S, Graham RD, Verma N, Trevathan JK, Franke M, Nieuwoudt S, Fisher LE, Shoffstall AJ, Weber DJ, Ludwig KA, Lempka SF. Computational modeling of dorsal root ganglion stimulation using an Injectrode. J Neural Eng 2024; 21:026039. [PMID: 38502956 PMCID: PMC11007586 DOI: 10.1088/1741-2552/ad357f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 02/23/2024] [Accepted: 03/19/2024] [Indexed: 03/21/2024]
Abstract
Objective.Minimally invasive neuromodulation therapies like the Injectrode, which is composed of a tightly wound polymer-coated Platinum/Iridium microcoil, offer a low-risk approach for administering electrical stimulation to the dorsal root ganglion (DRG). This flexible electrode is aimed to conform to the DRG. The stimulation occurs through a transcutaneous electrical stimulation (TES) patch, which subsequently transmits the stimulation to the Injectrode via a subcutaneous metal collector. However, it is important to note that the effectiveness of stimulation through TES relies on the specific geometrical configurations of the Injectrode-collector-patch system. Hence, there is a need to investigate which design parameters influence the activation of targeted neural structures.Approach.We employed a hybrid computational modeling approach to analyze the impact of Injectrode system design parameters on charge delivery and neural response to stimulation. We constructed multiple finite element method models of DRG stimulation, followed by the implementation of multi-compartment models of DRG neurons. By calculating potential distribution during monopolar stimulation, we simulated neural responses using various parameters based on prior acute experiments. Additionally, we developed a canonical monopolar stimulation and full-scale model of bipolar bilateral L5 DRG stimulation, allowing us to investigate how design parameters like Injectrode size and orientation influenced neural activation thresholds.Main results.Our findings were in accordance with acute experimental measurements and indicate that the minimally invasive Injectrode system predominantly engages large-diameter afferents (Aβ-fibers). These activation thresholds were contingent upon the surface area of the Injectrode. As the charge density decreased due to increasing surface area, there was a corresponding expansion in the stimulation amplitude range before triggering any pain-related mechanoreceptor (Aδ-fibers) activity.Significance.The Injectrode demonstrates potential as a viable technology for minimally invasive stimulation of the DRG. Our findings indicate that utilizing a larger surface area Injectrode enhances the therapeutic margin, effectively distinguishing the desired Aβactivation from the undesired Aδ-fiber activation.
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Affiliation(s)
- Sauradeep Bhowmick
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, United States of America
| | - Robert D Graham
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, United States of America
| | - Nishant Verma
- Department of Biomedical Engineering, University of Wisconsin–Madison, Madison, WI, United States of America
- Wisconsin Institute for Translational Neuroengineering (WITNe)–Madison, Madison, WI, United States of America
| | - James K Trevathan
- Department of Biomedical Engineering, University of Wisconsin–Madison, Madison, WI, United States of America
- Wisconsin Institute for Translational Neuroengineering (WITNe)–Madison, Madison, WI, United States of America
| | | | | | - Lee E Fisher
- Rehab Neural Engineering Labs (RNEL), Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Andrew J Shoffstall
- Neuronoff Inc., Cleveland, OH, United States of America
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States of America
| | - Douglas J Weber
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, United States of America
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA, United States of America
| | - Kip A Ludwig
- Department of Biomedical Engineering, University of Wisconsin–Madison, Madison, WI, United States of America
- Wisconsin Institute for Translational Neuroengineering (WITNe)–Madison, Madison, WI, United States of America
- Department of Neurosurgery, University of Wisconsin–Madison, Madison, WI, United States of America
| | - Scott F Lempka
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, United States of America
- Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States of America
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Wernisch L, Edwards T, Berthon A, Tessier-Lariviere O, Sarkans E, Stoukidi M, Fortier-Poisson P, Pinkney M, Thornton M, Hanley C, Lee S, Jennings J, Appleton B, Garsed P, Patterson B, Buttinger W, Gonshaw S, Jakopec M, Shunmugam S, Mamen J, Tukiainen A, Lajoie G, Armitage O, Hewage E. Online Bayesian optimization of vagus nerve stimulation. J Neural Eng 2024; 21:026019. [PMID: 38479016 DOI: 10.1088/1741-2552/ad33ae] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 03/13/2024] [Indexed: 04/04/2024]
Abstract
Objective.In bioelectronic medicine, neuromodulation therapies induce neural signals to the brain or organs, modifying their function. Stimulation devices capable of triggering exogenous neural signals using electrical waveforms require a complex and multi-dimensional parameter space to control such waveforms. Determining the best combination of parameters (waveform optimization or dosing) for treating a particular patient's illness is therefore challenging. Comprehensive parameter searching for an optimal stimulation effect is often infeasible in a clinical setting due to the size of the parameter space. Restricting this space, however, may lead to suboptimal therapeutic results, reduced responder rates, and adverse effects.Approach. As an alternative to a full parameter search, we present a flexible machine learning, data acquisition, and processing framework for optimizing neural stimulation parameters, requiring as few steps as possible using Bayesian optimization. This optimization builds a model of the neural and physiological responses to stimulations, enabling it to optimize stimulation parameters and provide estimates of the accuracy of the response model. The vagus nerve (VN) innervates, among other thoracic and visceral organs, the heart, thus controlling heart rate (HR), making it an ideal candidate for demonstrating the effectiveness of our approach.Main results.The efficacy of our optimization approach was first evaluated on simulated neural responses, then applied to VN stimulation intraoperatively in porcine subjects. Optimization converged quickly on parameters achieving target HRs and optimizing neural B-fiber activations despite high intersubject variability.Significance.An optimized stimulation waveform was achieved in real time with far fewer stimulations than required by alternative optimization strategies, thus minimizing exposure to side effects. Uncertainty estimates helped avoiding stimulations outside a safe range. Our approach shows that a complex set of neural stimulation parameters can be optimized in real-time for a patient to achieve a personalized precision dosing.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Guillaume Lajoie
- Université de Montréal and Mila-Quebec AI Institute, Montréal, Canada
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Nicolai EN, Larco JA, Madhani SI, Asirvatham SJ, Chang SY, Ludwig KA, Savastano LE, Worrell GA. Vagus nerve stimulation using an endovascular electrode array. J Neural Eng 2023; 20:10.1088/1741-2552/acdb9b. [PMID: 37276858 PMCID: PMC11123606 DOI: 10.1088/1741-2552/acdb9b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 06/05/2023] [Indexed: 06/07/2023]
Abstract
Objective. Vagus nerve stimulation (VNS), which involves a surgical procedure to place electrodes directly on the vagus nerve (VN), is approved clinically for the treatment of epilepsy, depression, and to facilitate rehabilitation in stroke. VNS at surgically implanted electrodes is often limited by activation of motor nerve fibers near and within the VN that cause neck muscle contraction. In this study we investigated endovascular VNS that may allow activation of the VN at locations where the motor nerve fibers are not localized.Approach. We used endovascular electrodes within the nearby internal jugular vein (IJV) to electrically stimulate the VN while recording VN compound action potentials (CAPs) and neck muscle motor evoked potentials (MEPs) in an acute intraoperative swine experiment.Main Results. We show that the stimulation electrode position within the IJV is critical for efficient activation of the VN. We also demonstrate use of fluoroscopy (cone beam CT mode) and ultrasound to determine the position of the endovascular stimulation electrode with respect to the VN and IJV. At the most effective endovascular stimulation locations tested, thresholds for VN activation were several times higher than direct stimulation of the nerve using a cuff electrode; however, this work demonstrates the feasibility of VNS with endovascular electrodes and provides tools to optimize endovascular electrode positions for VNS.Significance. This work lays the foundation to develop endovascular VNS strategies to stimulate at VN locations that would be otherwise too invasive and at VN locations where structures such as motor nerve fibers do not exist.
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Affiliation(s)
- Evan N. Nicolai
- Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Rochester, MN, USA
| | - Jorge Arturo Larco
- Department of Radiology, Mayo Clinic, Rochester, MN, USA
- Department of Neurosurgery, Mayo Clinic, Rochester, MN, USA
| | - Sarosh I. Madhani
- Department of Neurosurgery, University of California-San Francisco, San Francisco, CA, USA
| | | | - Su-youne Chang
- Department of Neurosurgery, Mayo Clinic, Rochester, MN, USA
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Kip A. Ludwig
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA
- Wisconsin Institute for Translational Neuroengineering (WITNe), University of Wisconsin-Madison, Madison, WI, USA
- Department of Neurological Surgery, University of Wisconsin-Madison, Madison, WI, USA
| | - Luis E. Savastano
- Department of Neurosurgery, University of California-San Francisco, San Francisco, CA, USA
| | - Gregory A. Worrell
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
- Department of Neurology, Mayo Clinic, Rochester, MN, USA
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Lim J, Eiber CD, Sun A, Maples A, Powley TL, Ward MP, Lee H. Fractal Microelectrodes for More Energy-Efficient Cervical Vagus Nerve Stimulation. Adv Healthc Mater 2023; 12:e2202619. [PMID: 36973998 PMCID: PMC10522801 DOI: 10.1002/adhm.202202619] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 03/06/2023] [Indexed: 03/29/2023]
Abstract
Vagus nerve stimulation (VNS) has the potential to treat various peripheral dysfunctions, but the traditional cuff electrodes for VNS are susceptible to off-target effects. Microelectrodes may enable highly selective VNS that can mitigate off-target effects, but they suffer from the increased impedance. Recent studies on microelectrodes with non-Euclidean geometries have reported higher energy efficiency in neural stimulation applications. These previous studies use electrodes with mm/cm-scale dimensions, mostly targeted for myelinated fibers. This study evaluates fractal microelectrodes for VNS in a rodent model (N = 3). A thin-film device with fractal and circle microelectrodes is fabricated to compare their neural stimulation performance on the same radial coordinate of the nerve. The results show that fractal microelectrodes can activate C-fibers with up to 52% less energy (p = 0.012) compared to circle microelectrodes. To the best of the knowledge, this work is the first to demonstrate a geometric advantage of fractal microelectrodes for VNS in vivo.
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Affiliation(s)
- Jongcheon Lim
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, IN, 47907, USA
- Center for Implantable Devices, Purdue University, West Lafayette, IN, 47907, USA
| | - Calvin D Eiber
- Synchron Inc., Melbourne, VIC, 3004, Australia
- Department of Medicine (RMH), Faculty of Medicine, Health and Dentistry, the University of Melbourne, Melbourne, VIC, 3050, Australia
| | - Anina Sun
- Department of Biology, Purdue University, West Lafayette, IN, 47907, USA
| | - Amanda Maples
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, 47907, USA
| | - Terry L Powley
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, 47907, USA
- Department of Psychological Sciences, Purdue University, West Lafayette, IN, 47907, USA
- Purdue Institute of Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Matthew P Ward
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, 47907, USA
- Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Hyowon Lee
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, IN, 47907, USA
- Center for Implantable Devices, Purdue University, West Lafayette, IN, 47907, USA
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Suminski AJ, Rajala AZ, Birn RM, Mueller EM, Malone ME, Ness JP, Filla C, Brunner K, McMillan AB, Poore SO, Williams JC, Murali D, Brzeczkowski A, Hurley SA, Dingle AM, Zeng W, Lake WB, Ludwig KA, Populin LC. Vagus nerve stimulation in the non-human primate: implantation methodology, characterization of nerve anatomy, target engagement and experimental applications. Bioelectron Med 2023; 9:9. [PMID: 37118841 PMCID: PMC10148417 DOI: 10.1186/s42234-023-00111-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 04/19/2023] [Indexed: 04/30/2023] Open
Abstract
BACKGROUND Vagus nerve stimulation (VNS) is a FDA approved therapy regularly used to treat a variety of neurological disorders that impact the central nervous system (CNS) including epilepsy and stroke. Putatively, the therapeutic efficacy of VNS results from its action on neuromodulatory centers via projections of the vagus nerve to the solitary tract nucleus. Currently, there is not an established large animal model that facilitates detailed mechanistic studies exploring how VNS impacts the function of the CNS, especially during complex behaviors requiring motor action and decision making. METHODS We describe the anatomical organization, surgical methodology to implant VNS electrodes on the left gagus nerve and characterization of target engagement/neural interface properties in a non-human primate (NHP) model of VNS that permits chronic stimulation over long periods of time. Furthermore, we describe the results of pilot experiments in a small number of NHPs to demonstrate how this preparation might be used in an animal model capable of performing complex motor and decision making tasks. RESULTS VNS electrode impedance remained constant over months suggesting a stable interface. VNS elicited robust activation of the vagus nerve which resulted in decreases of respiration rate and/or partial pressure of carbon dioxide in expired air, but not changes in heart rate in both awake and anesthetized NHPs. CONCLUSIONS We anticipate that this preparation will be very useful to study the mechanisms underlying the effects of VNS for the treatment of conditions such as epilepsy and depression, for which VNS is extensively used, as well as for the study of the neurobiological basis underlying higher order functions such as learning and memory.
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Affiliation(s)
- Aaron J Suminski
- Department of Neurological Surgery, University of Wisconsin-Madison, Madison, WI, USA
- Wisconsin Institute for Translational Neuroengineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Abigail Z Rajala
- Department of Neuroscience, University of Wisconsin-Madison, 1111 Highland Ave, Madison, WI, 53705, USA
| | - Rasmus M Birn
- Department of Psychiatry, University of Wisconsin-Madison, Madison, WI, USA
| | - Ellie M Mueller
- Department of Neuroscience, University of Wisconsin-Madison, 1111 Highland Ave, Madison, WI, 53705, USA
| | - Margaret E Malone
- Department of Neuroscience, University of Wisconsin-Madison, 1111 Highland Ave, Madison, WI, 53705, USA
| | - Jared P Ness
- Wisconsin Institute for Translational Neuroengineering, University of Wisconsin-Madison, Madison, WI, USA
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Caitlyn Filla
- Department of Neuroscience, University of Wisconsin-Madison, 1111 Highland Ave, Madison, WI, 53705, USA
| | - Kevin Brunner
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, WI, USA
| | - Alan B McMillan
- Department of Radiology, University of Wisconsin-Madison, Madison, WI, USA
- Department of Medical Physics, University of Wisconsin-Madison, Madison, WI, USA
| | - Samuel O Poore
- Division of Plastic Surgery, University of Wisconsin-Madison, Madison, WI, USA
| | - Justin C Williams
- Department of Neurological Surgery, University of Wisconsin-Madison, Madison, WI, USA
- Wisconsin Institute for Translational Neuroengineering, University of Wisconsin-Madison, Madison, WI, USA
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Dhanabalan Murali
- Department of Medical Physics, University of Wisconsin-Madison, Madison, WI, USA
| | - Andrea Brzeczkowski
- Department of Neurological Surgery, University of Wisconsin-Madison, Madison, WI, USA
- Wisconsin Institute for Translational Neuroengineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Samuel A Hurley
- Department of Radiology, University of Wisconsin-Madison, Madison, WI, USA
| | - Aaron M Dingle
- Division of Plastic Surgery, University of Wisconsin-Madison, Madison, WI, USA
| | - Weifeng Zeng
- Division of Plastic Surgery, University of Wisconsin-Madison, Madison, WI, USA
| | - Wendell B Lake
- Department of Neurological Surgery, University of Wisconsin-Madison, Madison, WI, USA
- Wisconsin Institute for Translational Neuroengineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Kip A Ludwig
- Department of Neurological Surgery, University of Wisconsin-Madison, Madison, WI, USA
- Wisconsin Institute for Translational Neuroengineering, University of Wisconsin-Madison, Madison, WI, USA
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Luis C Populin
- Department of Neuroscience, University of Wisconsin-Madison, 1111 Highland Ave, Madison, WI, 53705, USA.
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Verma N, Knudsen B, Gholston A, Skubal A, Blanz S, Settell M, Frank J, Trevathan J, Ludwig K. Microneurography as a minimally invasive method to assess target engagement during neuromodulation. J Neural Eng 2023; 20:10.1088/1741-2552/acc35c. [PMID: 36898148 PMCID: PMC10587909 DOI: 10.1088/1741-2552/acc35c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 03/10/2023] [Indexed: 03/12/2023]
Abstract
Objective.Peripheral neural signals recorded during neuromodulation therapies provide insights into local neural target engagement and serve as a sensitive biomarker of physiological effect. Although these applications make peripheral recordings important for furthering neuromodulation therapies, the invasive nature of conventional nerve cuffs and longitudinal intrafascicular electrodes (LIFEs) limit their clinical utility. Furthermore, cuff electrodes typically record clear asynchronous neural activity in small animal models but not in large animal models. Microneurography, a minimally invasive technique, is already used routinely in humans to record asynchronous neural activity in the periphery. However, the relative performance of microneurography microelectrodes compared to cuff and LIFE electrodes in measuring neural signals relevant to neuromodulation therapies is not well understood.Approach.To address this gap, we recorded cervical vagus nerve electrically evoked compound action potentials (ECAPs) and spontaneous activity in a human-scaled large animal model-the pig. Additionally, we recorded sensory evoked activity and both invasively and non-invasively evoked CAPs from the great auricular nerve. In aggregate, this study assesses the potential of microneurography electrodes to measure neural activity during neuromodulation therapies with statistically powered and pre-registered outcomes (https://osf.io/y9k6j).Main results.The cuff recorded the largest ECAP signal (p< 0.01) and had the lowest noise floor amongst the evaluated electrodes. Despite the lower signal to noise ratio, microneurography electrodes were able to detect the threshold for neural activation with similar sensitivity to cuff and LIFE electrodes once a dose-response curve was constructed. Furthermore, the microneurography electrodes recorded distinct sensory evoked neural activity.Significance.The results show that microneurography electrodes can measure neural signals relevant to neuromodulation therapies. Microneurography could further neuromodulation therapies by providing a real-time biomarker to guide electrode placement and stimulation parameter selection to optimize local neural fiber engagement and study mechanisms of action.
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Affiliation(s)
- Nishant Verma
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, United States of America
| | - Bruce Knudsen
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, United States of America
| | - Aaron Gholston
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, United States of America
| | - Aaron Skubal
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, United States of America
| | - Stephan Blanz
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, United States of America
| | - Megan Settell
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, United States of America
| | - Jennifer Frank
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
| | - James Trevathan
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, United States of America
| | - Kip Ludwig
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, United States of America
- Department of Neurosurgery, University of Wisconsin-Madison, Madison, WI, United States of America
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9
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Kronsteiner B, Haberbusch M, Aigner P, Kramer AM, Pilz PM, Podesser BK, Kiss A, Moscato F. A novel ex-vivo isolated rabbit heart preparation to explore the cardiac effects of cervical and cardiac vagus nerve stimulation. Sci Rep 2023; 13:4214. [PMID: 36918673 PMCID: PMC10014867 DOI: 10.1038/s41598-023-31135-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 03/07/2023] [Indexed: 03/15/2023] Open
Abstract
The cardiac responses to vagus nerve stimulation (VNS) are still not fully understood, partly due to uncontrollable confounders in the in-vivo experimental condition. Therefore, an ex-vivo Langendorff-perfused rabbit heart with intact vagal innervation is proposed to study VNS in absence of cofounding anesthetic or autonomic influences. The feasibility to evoke chronotropic responses through electrical stimulation ex-vivo was studied in innervated isolated rabbit hearts (n = 6). The general nerve excitability was assessed through the ability to evoke a heart rate (HR) reduction of at least 5 bpm (physiological threshold). The excitability was quantified as the charge needed for a 10-bpm HR reduction. The results were compared to a series of in-vivo experiments rabbits (n = 5). In the ex-vivo isolated heart, the baseline HR was about 20 bpm lower than in-vivo (158 ± 11 bpm vs 181 ± 19 bpm). Overall, the nerve remained excitable for about 5 h ex-vivo. The charges required to reduce HR by 5 bpm were 9 ± 6 µC and 549 ± 370 µC, ex-vivo and in-vivo, respectively. The charges needed for a 10-bpm HR reduction, normalized to the physiological threshold were 1.78 ± 0.8 and 1.22 ± 0.1, in-vivo and ex-vivo, respectively. Overall, the viability of this ex-vivo model to study the acute cardiac effects of VNS was demonstrated.
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Affiliation(s)
- Bettina Kronsteiner
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.
- Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria.
| | - Max Haberbusch
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
- Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria
| | - Philipp Aigner
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
- Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria
| | - Anne-Margarethe Kramer
- Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria
- Center for Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Patrick M Pilz
- Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria
- Center for Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Bruno K Podesser
- Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria
- Center for Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Attila Kiss
- Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria
- Center for Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Francesco Moscato
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
- Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria
- Austrian Cluster for Tissue Engineering, Vienna, Austria
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10
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Agnesi F, Zinno C, Strauss I, Dushpanova A, Casieri V, Bernini F, Terlizzi D, Gabisonia K, Lionetti V, Micera S. Cardiovascular Response to Intraneural Right Vagus Nerve Stimulation in Adult Minipig. Neuromodulation 2023:S1094-7159(23)00131-9. [PMID: 36997453 DOI: 10.1016/j.neurom.2023.03.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 02/27/2023] [Accepted: 03/06/2023] [Indexed: 03/31/2023]
Abstract
OBJECTIVE This study explored intraneural stimulation of the right thoracic vagus nerve (VN) in sexually mature male minipigs to modulate safe heart rate and blood pressure response. MATERIAL AND METHODS We employed an intraneural electrode designed for the VN of pigs to perform VN stimulation (VNS). This was delivered using different numbers of contacts on the electrode and different stimulation parameters (amplitude, frequency, and pulse width), identifying the most suitable stimulation configuration. All the parameter ranges had been selected from a computational cardiovascular system model. RESULTS Clinically relevant responses were observed when stimulating with low current intensities and relatively low frequencies delivered with a single contact. Selecting a biphasic, charge-balanced square wave for VNS with a current amplitude of 500 μA, frequency of 10 Hz, and pulse width of 200 μs, we obtained heart rate reduction of 7.67 ± 5.19 beats per minute, systolic pressure reduction of 5.75 ± 2.59 mmHg, and diastolic pressure reduction of 3.39 ± 1.44 mmHg. CONCLUSION Heart rate modulation was obtained without inducing any observable adverse effects, underlining the high selectivity of the intraneural approach.
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Affiliation(s)
- Filippo Agnesi
- BioRobotics Institute, Department of Excellence in Robotics & AI, Scuola Superiore Sant'Anna, Pisa, Italy
| | - Ciro Zinno
- BioRobotics Institute, Department of Excellence in Robotics & AI, Scuola Superiore Sant'Anna, Pisa, Italy
| | - Ivo Strauss
- Institut für Mikrosystemtechnik, University of Frieberg, IMTEK, Freiburg, Germany
| | - Anar Dushpanova
- Unit of Translational Critical Care Medicine, Laboratory of Basic and Applied Medical Sciences, Interdisciplinary Research Center "Health Science," Scuola Superiore Sant'Anna, Pisa, Italy; Health Research Institute, Al-Farabi Kazakh National University, Almaty, Kazakhstan
| | - Valentina Casieri
- Unit of Translational Critical Care Medicine, Laboratory of Basic and Applied Medical Sciences, Interdisciplinary Research Center "Health Science," Scuola Superiore Sant'Anna, Pisa, Italy; BioMedLab, Scuola Superiore Sant'Anna, Pisa, Italy
| | | | | | | | - Vincenzo Lionetti
- Unit of Translational Critical Care Medicine, Laboratory of Basic and Applied Medical Sciences, Interdisciplinary Research Center "Health Science," Scuola Superiore Sant'Anna, Pisa, Italy; BioMedLab, Scuola Superiore Sant'Anna, Pisa, Italy
| | - Silvestro Micera
- BioRobotics Institute, Department of Excellence in Robotics & AI, Scuola Superiore Sant'Anna, Pisa, Italy; Bertarelli Foundation Chair in Translational NeuroEngineering, Centre for Neuroprosthetics and Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
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11
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Verma N, Romanauski B, Lam D, Lujan L, Blanz S, Ludwig K, Lempka S, Shoffstall A, Knudson B, Nishiyama Y, Hao J, Park HJ, Ross E, Lavrov I, Zhang M. Characterization and applications of evoked responses during epidural electrical stimulation. Bioelectron Med 2023; 9:5. [PMID: 36855060 PMCID: PMC9976490 DOI: 10.1186/s42234-023-00106-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 02/08/2023] [Indexed: 03/02/2023] Open
Abstract
BACKGROUND Epidural electrical stimulation (EES) of the spinal cord has been FDA approved and used therapeutically for decades. However, there is still not a clear understanding of the local neural substrates and consequently the mechanism of action responsible for the therapeutic effects. METHOD Epidural spinal recordings (ESR) are collected from the electrodes placed in the epidural space. ESR contains multi-modality signal components such as the evoked neural response (due to tonic or BurstDR™ waveforms), evoked muscle response, stimulation artifact, and cardiac response. The tonic stimulation evoked compound action potential (ECAP) is one of the components in ESR and has been proposed recently to measure the accumulative local potentials from large populations of neuronal fibers during EES. RESULT Here, we first review and investigate the referencing strategies, as they apply to ECAP component in ESR in the domestic swine animal model. We then examine how ECAP component can be used to sense lead migration, an adverse outcome following lead placement that can reduce therapeutic efficacy. Lastly, we show and isolate concurrent activation of local back and leg muscles during EES, demonstrating that the ESR obtained from the recording contacts contain both ECAP and EMG components. CONCLUSION These findings may further guide the implementation of recording and reference contacts in an implantable EES system and provide preliminary evidence for the utility of ECAP component in ESR to detect lead migration. We expect these results to facilitate future development of EES methodology and implementation of use of different components in ESR to improve EES therapy.
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Affiliation(s)
- Nishant Verma
- Abbott Neuromodulation, 6901 Preston Rd, Plano, TX, 75024, USA
- Department of Biomedical Engineering, University of Wisconsin Madison, Madison, USA
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, USA
| | - Ben Romanauski
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA
| | - Danny Lam
- Abbott Neuromodulation, 6901 Preston Rd, Plano, TX, 75024, USA
| | - Luis Lujan
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Stephan Blanz
- Department of Biomedical Engineering, University of Wisconsin Madison, Madison, USA
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, USA
- University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Kip Ludwig
- Department of Biomedical Engineering, University of Wisconsin Madison, Madison, USA
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, USA
- Department of Neurosurgery, University of Wisconsin-Madison, Madison, WI, USA
| | - Scott Lempka
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
- APT Center, Louis Stokes Cleveland VA Medical Center, OH, Cleveland, USA
- Department of Biomedical Engineering, Department of Anesthesiology, Biointerfaces Institute, University of Michigan, Ann Arbor, MI, USA
| | - Andrew Shoffstall
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
- APT Center, Louis Stokes Cleveland VA Medical Center, OH, Cleveland, USA
| | - Bruce Knudson
- Department of Biomedical Engineering, University of Wisconsin Madison, Madison, USA
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, USA
| | - Yuichiro Nishiyama
- Department of Neurology, Department of Physiology and Biomedical Engineering, Mayo Clinic, 500 First Street SW, Rochester, MN, 55905, USA
| | - Jian Hao
- Department of Neurology, Department of Physiology and Biomedical Engineering, Mayo Clinic, 500 First Street SW, Rochester, MN, 55905, USA
| | - Hyun-Joo Park
- Abbott Neuromodulation, 6901 Preston Rd, Plano, TX, 75024, USA
| | - Erika Ross
- Abbott Neuromodulation, 6901 Preston Rd, Plano, TX, 75024, USA
| | - Igor Lavrov
- Department of Neurology, Department of Physiology and Biomedical Engineering, Mayo Clinic, 500 First Street SW, Rochester, MN, 55905, USA.
| | - Mingming Zhang
- Abbott Neuromodulation, 6901 Preston Rd, Plano, TX, 75024, USA.
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12
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Blanz SL, Musselman ED, Settell ML, Knudsen BE, Nicolai EN, Trevathan JK, Verner RS, Begnaud J, Skubal AC, Suminski AJ, Williams JC, Shoffstall AJ, Grill WM, Pelot NA, Ludwig KA. Spatially selective stimulation of the pig vagus nerve to modulate target effect versus side effect. J Neural Eng 2023; 20:10.1088/1741-2552/acb3fd. [PMID: 36649655 PMCID: PMC10339030 DOI: 10.1088/1741-2552/acb3fd] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 01/17/2023] [Indexed: 01/18/2023]
Abstract
Electrical stimulation of the cervical vagus nerve using implanted electrodes (VNS) is FDA-approved for the treatment of drug-resistant epilepsy, treatment-resistant depression, and most recently, chronic ischemic stroke rehabilitation. However, VNS is critically limited by the unwanted stimulation of nearby neck muscles-a result of non-specific stimulation activating motor nerve fibers within the vagus. Prior studies suggested that precise placement of small epineural electrodes can modify VNS therapeutic effects, such as cardiac responses. However, it remains unclear if placement can alter the balance between intended effect and limiting side effect. We used an FDA investigational device exemption approved six-contact epineural cuff to deliver VNS in pigs and quantified how epineural electrode location impacts on- and off-target VNS activation. Detailed post-mortem histology was conducted to understand how the underlying neuroanatomy impacts observed functional responses. Here we report the discovery and characterization of clear neuroanatomy-dependent differences in threshold and saturation for responses related to both effect (change in heart rate) and side effect (neck muscle contractions). The histological and electrophysiological data were used to develop and validate subject-specific computation models of VNS, creating a well-grounded quantitative framework to optimize electrode location-specific activation of nerve fibers governing intended effect versus unwanted side effect.
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Affiliation(s)
- Stephan L Blanz
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, United States of America
- University of Wisconsin School of Medicine and Public Health, Madison, WI, United States of America
| | - Eric D Musselman
- Department of Biomedical Engineering, Duke University, Durham, NC, United States of America
| | - Megan L Settell
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, United States of America
| | - Bruce E Knudsen
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, United States of America
| | - Evan N Nicolai
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, United States of America
- Mayo Clinic Graduate School of Biomedical Sciences, Rochester, MN, United States of America
- Mayo Clinic, Rochester, MN, United States of America
| | - James K Trevathan
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, United States of America
| | - Ryan S Verner
- LivaNova USA Inc., Houston, TX, United States of America
| | - Jason Begnaud
- LivaNova USA Inc., Houston, TX, United States of America
| | - Aaron C Skubal
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, United States of America
| | - Aaron J Suminski
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, United States of America
- Department of Neurological Surgery, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Justin C Williams
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, United States of America
- Department of Neurological Surgery, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Andrew J Shoffstall
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States of America
- APT Center, Louis Stokes Cleveland VA Medical Center, Cleveland, OH, United States of America
| | - Warren M Grill
- University of Wisconsin School of Medicine and Public Health, Madison, WI, United States of America
- Department of Electrical and Computer Engineering, Duke University, Durham, NC, United States of America
- Department of Neurobiology, Duke University, Durham, NC, United States of America
- Department of Neurosurgery, Duke University, Durham, NC, United States of America
| | - Nicole A Pelot
- Department of Biomedical Engineering, Duke University, Durham, NC, United States of America
| | - Kip A Ludwig
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute for Translational Neuroengineering (WITNe), Madison, WI, United States of America
- Department of Neurological Surgery, University of Wisconsin-Madison, Madison, WI, United States of America
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13
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Huffman WJ, Musselman ED, Pelot NA, Grill WM. Measuring and modeling the effects of vagus nerve stimulation on heart rate and laryngeal muscles. Bioelectron Med 2023; 9:3. [PMID: 36797733 PMCID: PMC9936668 DOI: 10.1186/s42234-023-00107-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Accepted: 02/08/2023] [Indexed: 02/18/2023] Open
Abstract
BACKGROUND Reduced heart rate (HR) during vagus nerve stimulation (VNS) is associated with therapy for heart failure, but stimulation frequency and amplitude are limited by patient tolerance. An understanding of physiological responses to parameter adjustments would allow differential control of therapeutic and side effects. To investigate selective modulation of the physiological responses to VNS, we quantified the effects and interactions of parameter selection on two physiological outcomes: one related to therapy (reduced HR) and one related to side effects (laryngeal muscle EMG). METHODS We applied a broad range of stimulation parameters (mean pulse rates (MPR), intra-burst frequencies, and amplitudes) to the vagus nerve of anesthetized mice. We leveraged the in vivo recordings to parameterize and validate computational models of HR and laryngeal muscle activity across amplitudes and temporal patterns of VNS. We constructed a finite element model of excitation of fibers within the mouse cervical vagus nerve. RESULTS HR decreased with increased amplitude, increased MPR, and decreased intra-burst frequency. EMG increased with increased MPR. Preferential HR effects over laryngeal EMG effects required combined adjustments of amplitude and MPR. The model of HR responses highlighted contributions of ganglionic filtering to VNS-evoked changes in HR at high stimulation frequencies. Overlap in activation thresholds between small and large modeled fibers was consistent with the overlap in dynamic ranges of related physiological measures (HR and EMG). CONCLUSION The present study provides insights into physiological responses to VNS required for informed parameter adjustment to modulate selectively therapeutic effects and side effects.
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Affiliation(s)
- William J. Huffman
- grid.26009.3d0000 0004 1936 7961Department of Biomedical Engineering, Duke University, Fitzpatrick CIEMAS, Box 90281, Room 1427, 101 Science Drive, Durham, NC 27708-0281 USA
| | - Eric D. Musselman
- grid.26009.3d0000 0004 1936 7961Department of Biomedical Engineering, Duke University, Fitzpatrick CIEMAS, Box 90281, Room 1427, 101 Science Drive, Durham, NC 27708-0281 USA
| | - Nicole A. Pelot
- grid.26009.3d0000 0004 1936 7961Department of Biomedical Engineering, Duke University, Fitzpatrick CIEMAS, Box 90281, Room 1427, 101 Science Drive, Durham, NC 27708-0281 USA
| | - Warren M. Grill
- grid.26009.3d0000 0004 1936 7961Department of Biomedical Engineering, Duke University, Fitzpatrick CIEMAS, Box 90281, Room 1427, 101 Science Drive, Durham, NC 27708-0281 USA ,grid.26009.3d0000 0004 1936 7961Department of Electrical and Computer Engineering, Duke University, Durham, USA ,grid.26009.3d0000 0004 1936 7961Department of Neurobiology Engineering, Duke University, Durham, USA ,grid.26009.3d0000 0004 1936 7961Department of Neurosurgery Engineering, Duke University, Durham, USA
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14
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Jayaprakash N, Song W, Toth V, Vardhan A, Levy T, Tomaio J, Qanud K, Mughrabi I, Chang YC, Rob M, Daytz A, Abbas A, Nassrallah Z, Volpe BT, Tracey KJ, Al-Abed Y, Datta-Chaudhuri T, Miller L, Barbe MF, Lee SC, Zanos TP, Zanos S. Organ- and function-specific anatomical organization of vagal fibers supports fascicular vagus nerve stimulation. Brain Stimul 2023; 16:484-506. [PMID: 36773779 DOI: 10.1016/j.brs.2023.02.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 02/03/2023] [Accepted: 02/03/2023] [Indexed: 02/11/2023] Open
Abstract
Vagal fibers travel inside fascicles and form branches to innervate organs and regulate organ functions. Existing vagus nerve stimulation (VNS) therapies activate vagal fibers non-selectively, often resulting in reduced efficacy and side effects from non-targeted organs. The transverse and longitudinal arrangement of fibers inside the vagal trunk with respect to the functions they mediate and organs they innervate is unknown, however it is crucial for selective VNS. Using micro-computed tomography imaging, we tracked fascicular trajectories and found that, in swine, sensory and motor fascicles are spatially separated cephalad, close to the nodose ganglion, and merge caudad, towards the lower cervical and upper thoracic region; larynx-, heart- and lung-specific fascicles are separated caudad and progressively merge cephalad. Using quantified immunohistochemistry at single fiber level, we identified and characterized all vagal fibers and found that fibers of different morphological types are differentially distributed in fascicles: myelinated afferents and efferents occupy separate fascicles, myelinated and unmyelinated efferents also occupy separate fascicles, and small unmyelinated afferents are widely distributed within most fascicles. We developed a multi-contact cuff electrode to accommodate the fascicular structure of the vagal trunk and used it to deliver fascicle-selective cervical VNS in anesthetized and awake swine. Compound action potentials from distinct fiber types, and physiological responses from different organs, including laryngeal muscle, cough, breathing, and heart rate responses are elicited in a radially asymmetric manner, with consistent angular separations that agree with the documented fascicular organization. These results indicate that fibers in the trunk of the vagus nerve are anatomically organized according to functions they mediate and organs they innervate and can be asymmetrically activated by fascicular cervical VNS.
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Affiliation(s)
| | - Weiguo Song
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Viktor Toth
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | | | - Todd Levy
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | | | - Khaled Qanud
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | | | - Yao-Chuan Chang
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Moontahinaz Rob
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Anna Daytz
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
| | - Adam Abbas
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Zeinab Nassrallah
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
| | - Bruce T Volpe
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Kevin J Tracey
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Yousef Al-Abed
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | | | - Larry Miller
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | | | - Sunhee C Lee
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | | | - Stavros Zanos
- Feinstein Institutes for Medical Research, Manhasset, NY, USA; Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA; Elmezzi Graduate School of Molecular Medicine, Manhasset, NY, USA.
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15
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Yeap TB, Ab Mukmin L, Ang SY, Ghani AR. Perianaesthetic challenges in patients undergoing vagus nerve stimulation (VNS) placement. BMJ Case Rep 2023; 16:e252692. [PMID: 36750294 PMCID: PMC9906277 DOI: 10.1136/bcr-2022-252692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Patients with medically refractory epilepsy (MRE) are indicated for vagus nerve stimulation (VNS) placement. Anaesthesia for VNS placement is extremely challenging and requires several considerations. We present a man in his 20s with MRE who successfully underwent VNS placement. We review the mechanism of action of VNS, anaesthetic challenges and measures to prevent seizures.
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Affiliation(s)
- Tat Boon Yeap
- Faculty of Medicine and Health Sciences, Universiti Malaysia Sabah, Kota Kinabalu, Malaysia
| | - Laila Ab Mukmin
- Department of Anaesthesia and Intensive Care Unit, Hospital Universiti Sains Malaysia, Kota Bahru, Malaysia
| | - Song Yee Ang
- Department of Neurosciences, School of Medical Sciences, Hospital Universiti Sains Malaysia, Kota Bahru, Malaysia
| | - Ab Rahman Ghani
- Department of Neurosciences, School of Medical Sciences, Hospital Universiti Sains Malaysia, Kota Bahru, Malaysia
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16
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Saytashev I, Yoon YC, Vakoc BJ, Vasudevan S, Hammer DX. Improved in vivo optical coherence tomography imaging of animal peripheral nerves using a prism nerve holder. JOURNAL OF BIOMEDICAL OPTICS 2023; 28:026002. [PMID: 36785561 PMCID: PMC9921515 DOI: 10.1117/1.jbo.28.2.026002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 01/20/2023] [Indexed: 06/01/2023]
Abstract
Significance Modern optical volumetric imaging modalities, such as optical coherence tomography (OCT), provide enormous information about the structure, function, and physiology of living tissue. Although optical imaging achieves lateral resolution on the order of the wavelength of light used, and OCT achieves axial resolution on a similar micron scale, tissue optical properties, particularly high scattering and absorption, limit light penetration to only a few millimeters. In addition, in vivo imaging modalities are susceptible to significant motion artifacts due to cardiac and respiratory function. These effects limit access to artifact-free optical measurements during peripheral neurosurgery to only a portion of the exposed nerve without further modification to the procedure. Aim We aim to improve in vivo OCT imaging during peripheral neurosurgery in small and large animals by increasing the amount of visualized nerve volume as well as suppressing motion of the imaged area. Approach We designed a nerve holder with embedded mirror prisms for peripheral nerve volumetric imaging as well as a specific beam steering strategy to acquire prism and direct view volumes in one session with minimal motion artifacts. Results The axially imaged volumes from mirror prisms increased the OCT signal intensity by > 22 dB over a 1.25-mm imaging depth in tissue-mimicking phantoms. We then demonstrated the new imaging capabilities in visualizing peripheral nerves from direct and side views in living rats and minipigs using a polarization-sensitive OCT system. Prism views have shown nerve fascicles and vasculature from the bottom half of the imaged nerve which was not visible in direct view. Conclusions We demonstrated improved OCT imaging during neurosurgery in small and large animals by combining the use of a prism nerve holder with a specifically designed beam scanning protocol. Our strategy can be applied to existing OCT imaging systems with minimal hardware modification, increasing the nerve tissue volume visualized. Enhanced imaging depth techniques may lead to a greater adoption of structural and functional optical biomarkers in preclinical and clinical medicine.
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Affiliation(s)
- Ilyas Saytashev
- U. S. Food and Drug Administration, Center for Devices and Radiological Health, Office of Science and Engineering Laboratories, Silver Spring, Maryland, United States
| | - Yong-Chul Yoon
- Massachusetts General Hospital, Wellman Center for Photomedicine, Boston, Massachusetts, United States
| | - Benjamin J. Vakoc
- Massachusetts General Hospital, Wellman Center for Photomedicine, Boston, Massachusetts, United States
| | - Srikanth Vasudevan
- U. S. Food and Drug Administration, Center for Devices and Radiological Health, Office of Science and Engineering Laboratories, Silver Spring, Maryland, United States
| | - Daniel X. Hammer
- U. S. Food and Drug Administration, Center for Devices and Radiological Health, Office of Science and Engineering Laboratories, Silver Spring, Maryland, United States
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17
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Thompson N, Ravagli E, Mastitskaya S, Iacoviello F, Stathopoulou TR, Perkins J, Shearing PR, Aristovich K, Holder D. Organotopic organization of the porcine mid-cervical vagus nerve. Front Neurosci 2023; 17:963503. [PMID: 37205051 PMCID: PMC10185768 DOI: 10.3389/fnins.2023.963503] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 04/04/2023] [Indexed: 05/21/2023] Open
Abstract
Introduction Despite detailed characterization of fascicular organization of somatic nerves, the functional anatomy of fascicles evident in human and large mammal cervical vagus nerve is unknown. The vagus nerve is a prime target for intervention in the field of electroceuticals due to its extensive distribution to the heart, larynx, lungs, and abdominal viscera. However, current practice of the approved vagus nerve stimulation (VNS) technique is to stimulate the entire nerve. This produces indiscriminate stimulation of non-targeted effectors and undesired side effects. Selective neuromodulation is now a possibility with a spatially-selective vagal nerve cuff. However, this requires the knowledge of the fascicular organization at the level of cuff placement to inform selectivity of only the desired target organ or function. Methods and results We imaged function over milliseconds with fast neural electrical impedance tomography and selective stimulation, and found consistent spatially separated regions within the nerve correlating with the three fascicular groups of interest, suggesting organotopy. This was independently verified with structural imaging by tracing anatomical connections from the end organ with microCT and the development of an anatomical map of the vagus nerve. This confirmed organotopic organization. Discussion Here we show, for the first time, localized fascicles in the porcine cervical vagus nerve which map to cardiac, pulmonary and recurrent laryngeal function (N = 4). These findings pave the way for improved outcomes in VNS as unwanted side effects could be reduced by targeted selective stimulation of identified organ-specific fiber-containing fascicles and the extension of this technique clinically beyond the currently approved disorders to treat heart failure, chronic inflammatory disorders, and more.
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Affiliation(s)
- Nicole Thompson
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
- *Correspondence: Nicole Thompson,
| | - Enrico Ravagli
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Svetlana Mastitskaya
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Francesco Iacoviello
- Electrochemical Innovations Lab, Department of Chemical Engineering, University College London, London, United Kingdom
| | | | - Justin Perkins
- Department of Clinical Science and Services, The Royal Veterinary College, Hatfield, United Kingdom
| | - Paul R. Shearing
- Electrochemical Innovations Lab, Department of Chemical Engineering, University College London, London, United Kingdom
| | - Kirill Aristovich
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - David Holder
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
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18
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Brinkman DJ, Gupta I, Matteucci PB, Ouchouche S, de Jonge WJ, Coatney RW, Salam T, Chew DJ, Irwin E, Yazicioglu RF, Nieuwenhuizen GAP, Vervoordeldonk MJ, Luyer MDP. Splenic arterial neurovascular bundle stimulation in esophagectomy: A feasibility and safety prospective cohort study. Front Neurosci 2022; 16:1088628. [PMID: 36620453 PMCID: PMC9817142 DOI: 10.3389/fnins.2022.1088628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 12/02/2022] [Indexed: 12/24/2022] Open
Abstract
Introduction The autonomic nervous system is a key regulator of inflammation. Electrical stimulation of the vagus nerve has been shown to have some preclinical efficacy. However, only a few clinical studies have been reported to treat inflammatory diseases. The present study evaluates, for the first time, neuromodulation of the splenic arterial neurovascular bundle (SpA NVB) in patients undergoing minimally invasive esophagectomy (MIE), in which the SpA NVB is exposed as part of the procedure. Methods This single-center, single-arm study enrolled 13 patients undergoing MIE. During the abdominal phase of the MIE, a novel cuff was placed around the SpA NVB, and stimulation was applied. The primary endpoint was the feasibility and safety of cuff application and removal. A secondary endpoint included the impact of stimulation on SpA blood flow changes during the stimulation, and an exploratory point was C-reactive protein (CRP) levels on postoperative day (POD) 2 and 3. Results All patients successfully underwent placement, stimulation, and removal of the cuff on the SpA NVB with no adverse events related to the investigational procedure. Stimulation was associated with an overall reduction in splenic arterial blood flow but not with changes in blood pressure or heart rate. When compared to historic Propensity Score Matched (PSM) controls, CRP levels on POD2 (124 vs. 197 mg/ml, p = 0.032) and POD3 (151 vs. 221 mg/ml, p = 0.033) were lower in patients receiving stimulation. Conclusion This first-in-human study demonstrated for the first time that applying a cuff around the SpA NVB and subsequent stimulation is safe, feasible, and may have an effect on the postoperative inflammatory response following MIE. These findings suggest that SpA NVB stimulation may offer a new method for immunomodulatory therapy in acute or chronic inflammatory conditions.
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Affiliation(s)
- David J. Brinkman
- Department of Surgery, Catharina Hospital, Eindhoven, Netherlands,Tytgat Institute for Liver and Intestinal Research, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands,David J. Brinkman,
| | - Isha Gupta
- Galvani Bioelectronics, Stevenage, United Kingdom
| | | | | | - Wouter J. de Jonge
- Tytgat Institute for Liver and Intestinal Research, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | | | | | | | - Eric Irwin
- Galvani Bioelectronics, Stevenage, United Kingdom
| | | | | | | | - Misha D. P. Luyer
- Department of Surgery, Catharina Hospital, Eindhoven, Netherlands,*Correspondence: Misha D. P. Luyer,
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19
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Upadhye AR, Kolluru C, Druschel L, Lababidi LA, Ahmad SS, Menendez DM, Buyukcelik ON, Settell ML, Blanz SL, Jenkins MW, Wilson DL, Zhang J, Tatsuoka C, Grill WM, Pelot NA, Ludwig KA, Gustafson KJ, Shoffstall AJ. Fascicles split or merge every ∼560 microns within the human cervical vagus nerve. J Neural Eng 2022; 19:10.1088/1741-2552/ac9643. [PMID: 36174538 PMCID: PMC10353574 DOI: 10.1088/1741-2552/ac9643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 09/29/2022] [Indexed: 12/24/2022]
Abstract
Objective.Vagus nerve stimulation (VNS) is Food and Drug Administration-approved for epilepsy, depression, and obesity, and stroke rehabilitation; however, the morphological anatomy of the vagus nerve targeted by stimulatation is poorly understood. Here, we used microCT to quantify the fascicular structure and neuroanatomy of human cervical vagus nerves (cVNs).Approach.We collected eight mid-cVN specimens from five fixed cadavers (three left nerves, five right nerves). Analysis focused on the 'surgical window': 5 cm of length, centered around the VNS implant location. Tissue was stained with osmium tetroxide, embedded in paraffin, and imaged on a microCT scanner. We visualized and quantified the merging and splitting of fascicles, and report a morphometric analysis of fascicles: count, diameter, and area.Main results.In our sample of human cVNs, a fascicle split or merge event was observed every ∼560µm (17.8 ± 6.1 events cm-1). Mean morphological outcomes included: fascicle count (6.6 ± 2.8 fascicles; range 1-15), fascicle diameter (514 ± 142µm; range 147-1360µm), and total cross-sectional fascicular area (1.32 ± 0.41 mm2; range 0.58-2.27 mm).Significance.The high degree of fascicular splitting and merging, along with wide range in key fascicular morphological parameters across humans may help to explain the clinical heterogeneity in patient responses to VNS. These data will enable modeling and experimental efforts to determine the clinical effect size of such variation. These data will also enable efforts to design improved VNS electrodes.
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Affiliation(s)
- Aniruddha R. Upadhye
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States of America
- APT Center, Louis Stokes Cleveland VA Medical Center, Cleveland, OH, United States of America
| | - Chaitanya Kolluru
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States of America
| | - Lindsey Druschel
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States of America
- APT Center, Louis Stokes Cleveland VA Medical Center, Cleveland, OH, United States of America
| | - Luna Al Lababidi
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States of America
| | - Sami S. Ahmad
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States of America
| | - Dhariyat M. Menendez
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States of America
- APT Center, Louis Stokes Cleveland VA Medical Center, Cleveland, OH, United States of America
| | - Ozge N. Buyukcelik
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States of America
| | - Megan L. Settell
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Stephan L. Blanz
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute of Neuroengineering (WITNe), University of Wisconsin-Madison, Madison, WI, USA
| | - Michael W. Jenkins
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States of America
| | - David L. Wilson
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States of America
| | - Jing Zhang
- Department of Population and Quantitative Health Sciences, Case Western Reserve University, Cleveland, OH, United States of America
| | - Curtis Tatsuoka
- Department of Population and Quantitative Health Sciences, Case Western Reserve University, Cleveland, OH, United States of America
- FES Center, Louis Stokes Cleveland VA Medical Center, Cleveland, OH, United States of America
| | - Warren M. Grill
- Department of Biomedical Engineering, Duke University, Durham, NC, United States of America
- Department of Electrical and Computer Engineering, Duke University, Durham, NC, United States of America
- Department of Neurobiology, Duke University, Durham, NC, United States of America
- Department of Neurosurgery, Duke University, Durham, NC, United States of America
| | - Nicole A. Pelot
- Department of Biomedical Engineering, Duke University, Durham, NC, United States of America
| | - Kip A. Ludwig
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Department of Neurosurgery, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute of Neuroengineering (WITNe), University of Wisconsin-Madison, Madison, WI, USA
| | - Kenneth J. Gustafson
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States of America
- FES Center, Louis Stokes Cleveland VA Medical Center, Cleveland, OH, United States of America
| | - Andrew J. Shoffstall
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States of America
- APT Center, Louis Stokes Cleveland VA Medical Center, Cleveland, OH, United States of America
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20
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Chang YC, Ahmed U, Jayaprakash N, Mughrabi I, Lin Q, Wu YC, Gerber M, Abbas A, Daytz A, Gabalski AH, Ashville J, Dokos S, Rieth L, Datta-Chaudhuri T, Tracey KJ, Guo T, Al-Abed Y, Zanos S. kHz-frequency electrical stimulation selectively activates small, unmyelinated vagus afferents. Brain Stimul 2022; 15:1389-1404. [PMID: 36241025 PMCID: PMC10164362 DOI: 10.1016/j.brs.2022.09.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 09/02/2022] [Accepted: 09/30/2022] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Vagal reflexes regulate homeostasis in visceral organs and systems through afferent and efferent neurons and nerve fibers. Small, unmyelinated, C-type afferents comprise over 80% of fibers in the vagus and form the sensory arc of autonomic reflexes of the gut, lungs, heart and vessels and the immune system. Selective bioelectronic activation of C-afferents could be used to mechanistically study and treat diseases of peripheral organs in which vagal reflexes are involved, but it has not been achieved. METHODS We stimulated the vagus in rats and mice using trains of kHz-frequency stimuli. Stimulation effects were assessed using neuronal c-Fos expression, physiological and nerve fiber responses, optogenetic and computational methods. RESULTS Intermittent kHz stimulation for 30 min activates specific motor and, preferentially, sensory vagus neurons in the brainstem. At sufficiently high frequencies (>5 kHz) and at intensities within a specific range (7-10 times activation threshold, T, in rats; 15-25 × T in mice), C-afferents are activated, whereas larger, A- and B-fibers, are blocked. This was determined by measuring fiber-specific acute physiological responses to kHz stimulus trains, and by assessing fiber excitability around kHz stimulus trains through compound action potentials evoked by probing pulses. Aspects of selective activation of C-afferents are explained in computational models of nerve fibers by how fiber size and myelin shape the response of sodium channels to kHz-frequency stimuli. CONCLUSION kHz stimulation is a neuromodulation strategy to robustly and selectively activate vagal C-afferents implicated in physiological homeostasis and disease, over larger vagal fibers.
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Affiliation(s)
- Yao-Chuan Chang
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Umair Ahmed
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Naveen Jayaprakash
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Ibrahim Mughrabi
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Qihang Lin
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, 2052, Australia
| | - Yi-Chen Wu
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Michael Gerber
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Adam Abbas
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Anna Daytz
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Arielle H Gabalski
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Jason Ashville
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Socrates Dokos
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, 2052, Australia
| | - Loren Rieth
- Department of Mechanical and Aerospace Engineering, West Virginia University, Morgantown, WV, 26506, United States
| | - Timir Datta-Chaudhuri
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Kevin J Tracey
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Tianruo Guo
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, 2052, Australia
| | - Yousef Al-Abed
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Stavros Zanos
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States; Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, United States.
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21
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Arsava EM, Topcuoglu MA, Ay I, Ozdemir AO, Gungor IL, Togay Isikay C, Nazliel B, Kozak HH, Ozturk S, Yilmaz İA, Dora B, Ay H, Ozel T, Sorgun MH, Bahadır EA, Peker E, Aykac O, Mehdiyev Z, Caglayan HZB, Gurses AA, Pektezel MY, Yilmaz E, Oge DD, Parlak S, Bugrul A, Ozguner H, Seker AC, Ozdemir G, Ongun G, Yilmaz SE, Ozguncu C, Turan Isik SM, Ildiz OF, Mammadli A, Yildogan AT, McClure C. Assessment of safety and feasibility of non-invasive vagus nerve stimulation for treatment of acute stroke. Brain Stimul 2022; 15:1467-1474. [PMID: 36356829 DOI: 10.1016/j.brs.2022.10.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Revised: 10/16/2022] [Accepted: 10/31/2022] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Non-invasive vagus nerve stimulation (nVNS) using a hand-held stimulator placed on the neck is an FDA-approved treatment for primary headache disorders. The safety of nVNS is unknown in stroke patients. OBJECTIVE To assess the safety and feasibility of nVNS for the acute treatment of stroke. METHODS TR-VENUS (clinicaltrials.gov identifier NCT03733431) was a randomized, sham-controlled, open-label, multicenter trial conducted in patients with acute ischemic stroke (IS) or intracerebral hemorrhage (ICH). Patients were randomly assigned to standard-dose nVNS, high-dose nVNS, or sham stimulation. The primary endpoint was a composite safety outcome defined as bradycardia or reduction in mean arterial blood pressure during treatment or progression of neurological or death within 24 h of treatment. The feasibility endpoints were the proportion of eligible subjects receiving nVNS within 6 h of symptom onset and the proportion completing all pre-specified treatment doses. Efficacy assessments included infarct growth from baseline to 24 h after treatment. RESULTS Sixty-nine patients (61 IS, 8 ICH) completed the study. The composite safety outcome was achieved in 32.0% in sham and 47.7% in nVNS group (p = 0.203). Treatment was initiated in all but two randomized patients. All dosed subjects received 100% of prespecified stimulations. A non-significant reduction in infarct growth was observed in the high-dose nVNS group (184.2% in sham vs. 63.3% in high-dose nVNS; p = 0.109). CONCLUSIONS The results of this study suggest that nVNS may be safe and feasible in the setting of acute stroke. These findings support further development of nVNS as a potential treatment for acute ischemic stroke.
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Affiliation(s)
| | | | - Ilknur Ay
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | | | | | | | - Bijen Nazliel
- Department of Neurology, Gazi University, Ankara, Turkey
| | | | | | | | - Babur Dora
- Department of Neurology, Akdeniz University, Antalya, Turkey
| | - Hakan Ay
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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22
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Ottaviani MM, Vallone F, Micera S, Recchia FA. Closed-Loop Vagus Nerve Stimulation for the Treatment of Cardiovascular Diseases: State of the Art and Future Directions. Front Cardiovasc Med 2022; 9:866957. [PMID: 35463766 PMCID: PMC9021417 DOI: 10.3389/fcvm.2022.866957] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 03/14/2022] [Indexed: 01/07/2023] Open
Abstract
The autonomic nervous system exerts a fine beat-to-beat regulation of cardiovascular functions and is consequently involved in the onset and progression of many cardiovascular diseases (CVDs). Selective neuromodulation of the brain-heart axis with advanced neurotechnologies is an emerging approach to corroborate CVDs treatment when classical pharmacological agents show limited effectiveness. The vagus nerve is a major component of the cardiac neuroaxis, and vagus nerve stimulation (VNS) is a promising application to restore autonomic function under various pathological conditions. VNS has led to encouraging results in animal models of CVDs, but its translation to clinical practice has not been equally successful, calling for more investigation to optimize this technique. Herein we reviewed the state of the art of VNS for CVDs and discuss avenues for therapeutic optimization. Firstly, we provided a succinct description of cardiac vagal innervation anatomy and physiology and principles of VNS. Then, we examined the main clinical applications of VNS in CVDs and the related open challenges. Finally, we presented preclinical studies that aim at overcoming VNS limitations through optimization of anatomical targets, development of novel neural interface technologies, and design of efficient VNS closed-loop protocols.
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Affiliation(s)
- Matteo Maria Ottaviani
- Institute of Life Sciences, Scuola Superiore Sant’Anna, Pisa, Italy
- Department of Excellence in Robotics and Artificial Intelligence, The BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy
| | - Fabio Vallone
- Department of Excellence in Robotics and Artificial Intelligence, The BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy
| | - Silvestro Micera
- Department of Excellence in Robotics and Artificial Intelligence, The BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy
- Bertarelli Foundation Chair in Translational Neural Engineering, Center for Neuroprosthetics, Institute of Bioengineering, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland
| | - Fabio A. Recchia
- Institute of Life Sciences, Scuola Superiore Sant’Anna, Pisa, Italy
- Fondazione Toscana Gabriele Monasterio, Pisa, Italy
- Department of Physiology, Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, United States
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23
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Laryngeal Muscle-Evoked Potential Recording as an Indicator of Vagal Nerve Fiber Activation. Neuromodulation 2022; 25:461-470. [DOI: 10.1016/j.neurom.2022.01.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 11/30/2021] [Accepted: 01/04/2022] [Indexed: 11/20/2022]
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24
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Verma N, Graham RD, Mudge J, Trevathan JK, Franke M, Shoffstall AJ, Williams J, Dalrymple AN, Fisher LE, Weber DJ, Lempka SF, Ludwig KA. Augmented Transcutaneous Stimulation Using an Injectable Electrode: A Computational Study. Front Bioeng Biotechnol 2022; 9:796042. [PMID: 34988068 PMCID: PMC8722711 DOI: 10.3389/fbioe.2021.796042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 11/25/2021] [Indexed: 11/13/2022] Open
Abstract
Minimally invasive neuromodulation technologies seek to marry the neural selectivity of implantable devices with the low-cost and non-invasive nature of transcutaneous electrical stimulation (TES). The Injectrode® is a needle-delivered electrode that is injected onto neural structures under image guidance. Power is then transcutaneously delivered to the Injectrode using surface electrodes. The Injectrode serves as a low-impedance conduit to guide current to the deep on-target nerve, reducing activation thresholds by an order of magnitude compared to using only surface stimulation electrodes. To minimize off-target recruitment of cutaneous fibers, the energy transfer efficiency from the surface electrodes to the Injectrode must be optimized. TES energy is transferred to the Injectrode through both capacitive and resistive mechanisms. Electrostatic finite element models generally used in TES research consider only the resistive means of energy transfer by defining tissue conductivities. Here, we present an electroquasistatic model, taking into consideration both the conductivity and permittivity of tissue, to understand transcutaneous power delivery to the Injectrode. The model was validated with measurements taken from (n = 4) swine cadavers. We used the validated model to investigate system and anatomic parameters that influence the coupling efficiency of the Injectrode energy delivery system. Our work suggests the relevance of electroquasistatic models to account for capacitive charge transfer mechanisms when studying TES, particularly when high-frequency voltage components are present, such as those used for voltage-controlled pulses and sinusoidal nerve blocks.
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Affiliation(s)
- Nishant Verma
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States.,Wisconsin Institute for Translational Neuroengineering (WITNe)-Madison, Madison, WI, United States
| | - Robert D Graham
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States.,Biointerfaces Institute, University of Michigan, Ann Arbor, MI, United States
| | - Jonah Mudge
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States.,Wisconsin Institute for Translational Neuroengineering (WITNe)-Madison, Madison, WI, United States
| | - James K Trevathan
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States.,Wisconsin Institute for Translational Neuroengineering (WITNe)-Madison, Madison, WI, United States
| | | | - Andrew J Shoffstall
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
| | - Justin Williams
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States.,Wisconsin Institute for Translational Neuroengineering (WITNe)-Madison, Madison, WI, United States
| | - Ashley N Dalrymple
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, United States.,Rehab Neural Engineering Labs (RNEL), Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, United States
| | - Lee E Fisher
- Rehab Neural Engineering Labs (RNEL), Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, United States
| | - Douglas J Weber
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, United States.,Rehab Neural Engineering Labs (RNEL), Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, United States
| | - Scott F Lempka
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States.,Biointerfaces Institute, University of Michigan, Ann Arbor, MI, United States.,Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States
| | - Kip A Ludwig
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States.,Wisconsin Institute for Translational Neuroengineering (WITNe)-Madison, Madison, WI, United States.,Department of Neurosurgery, University of Wisconsin-Madison, Madison, WI, United States
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25
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Settell ML, Skubal AC, Chen RCH, Kasole M, Knudsen BE, Nicolai EN, Huang C, Zhou C, Trevathan JK, Upadhye A, Kolluru C, Shoffstall AJ, Williams JC, Suminski AJ, Grill WM, Pelot NA, Chen S, Ludwig KA. In vivo Visualization of Pig Vagus Nerve "Vagotopy" Using Ultrasound. Front Neurosci 2021; 15:676680. [PMID: 34899151 PMCID: PMC8660563 DOI: 10.3389/fnins.2021.676680] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 11/01/2021] [Indexed: 02/05/2023] Open
Abstract
Background: Placement of the clinical vagus nerve stimulating cuff is a standard surgical procedure based on anatomical landmarks, with limited patient specificity in terms of fascicular organization or vagal anatomy. As such, the therapeutic effects are generally limited by unwanted side effects of neck muscle contractions, demonstrated by previous studies to result from stimulation of (1) motor fibers near the cuff in the superior laryngeal and (2) motor fibers within the cuff projecting to the recurrent laryngeal. Objective: Conventional non-invasive ultrasound, where the transducer is placed on the surface of the skin, has been previously used to visualize the vagus with respect to other landmarks such as the carotid and internal jugular vein. However, it lacks sufficient resolution to provide details about the vagus fascicular organization, or detail about smaller neural structures such as the recurrent and superior laryngeal branch responsible for therapy limiting side effects. Here, we characterize the use of ultrasound with the transducer placed in the surgical pocket to improve resolution without adding significant additional risk to the surgical procedure in the pig model. Methods: Ultrasound images were obtained from a point of known functional organization at the nodose ganglia to the point of placement of stimulating electrodes within the surgical window. Naïve volunteers with minimal training were then asked to use these ultrasound videos to trace afferent groupings of fascicles from the nodose to their location within the surgical window where a stimulating cuff would normally be placed. Volunteers were asked to select a location for epineural electrode placement away from the fascicles containing efferent motor nerves responsible for therapy limiting side effects. 2-D and 3-D reconstructions of the ultrasound were directly compared to post-mortem histology in the same animals. Results: High-resolution ultrasound from the surgical pocket enabled 2-D and 3-D reconstruction of the cervical vagus and surrounding structures that accurately depicted the functional vagotopy of the pig vagus nerve as confirmed via histology. Although resolution was not sufficient to match specific fascicles between ultrasound and histology 1 to 1, it was sufficient to trace fascicle groupings from a point of known functional organization at the nodose ganglia to their locations within the surgical window at stimulating electrode placement. Naïve volunteers were able place an electrode proximal to the sensory afferent grouping of fascicles and away from the motor nerve efferent grouping of fascicles in each subject (n = 3). Conclusion: The surgical pocket itself provides a unique opportunity to obtain higher resolution ultrasound images of neural targets responsible for intended therapeutic effect and limiting off-target effects. We demonstrate the increase in resolution is sufficient to aid patient-specific electrode placement to optimize outcomes. This simple technique could be easily adopted for multiple neuromodulation targets to better understand how patient specific anatomy impacts functional outcomes.
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Affiliation(s)
- Megan L. Settell
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States
- Wisconsin Institute of Neuroengineering (WITNe), University of Wisconsin-Madison, Madison, WI, United States
| | - Aaron C. Skubal
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States
- Wisconsin Institute of Neuroengineering (WITNe), University of Wisconsin-Madison, Madison, WI, United States
| | - Rex C. H. Chen
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States
- Wisconsin Institute of Neuroengineering (WITNe), University of Wisconsin-Madison, Madison, WI, United States
| | - Maïsha Kasole
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States
- Wisconsin Institute of Neuroengineering (WITNe), University of Wisconsin-Madison, Madison, WI, United States
| | - Bruce E. Knudsen
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States
- Wisconsin Institute of Neuroengineering (WITNe), University of Wisconsin-Madison, Madison, WI, United States
| | - Evan N. Nicolai
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States
- Wisconsin Institute of Neuroengineering (WITNe), University of Wisconsin-Madison, Madison, WI, United States
- Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Rochester, MN, United States
| | - Chengwu Huang
- Department of Radiology, Mayo Clinic, Rochester, MN, United States
| | - Chenyun Zhou
- Department of Radiology, Mayo Clinic, Rochester, MN, United States
- Department of Ultrasound, West China Hospital of Sichuan University, Chengdu, China
| | - James K. Trevathan
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States
- Wisconsin Institute of Neuroengineering (WITNe), University of Wisconsin-Madison, Madison, WI, United States
| | - Aniruddha Upadhye
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Louis Stokes Cleveland VA Medical Center, Cleveland, OH, United States
| | - Chaitanya Kolluru
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Louis Stokes Cleveland VA Medical Center, Cleveland, OH, United States
| | - Andrew J. Shoffstall
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Louis Stokes Cleveland VA Medical Center, Cleveland, OH, United States
| | - Justin C. Williams
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States
- Wisconsin Institute of Neuroengineering (WITNe), University of Wisconsin-Madison, Madison, WI, United States
- Department of Neurosurgery, University of Wisconsin-Madison, Madison, WI, United States
| | - Aaron J. Suminski
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States
- Wisconsin Institute of Neuroengineering (WITNe), University of Wisconsin-Madison, Madison, WI, United States
- Department of Neurosurgery, University of Wisconsin-Madison, Madison, WI, United States
| | - Warren M. Grill
- Department of Biomedical Engineering, Duke University, Durham, NC, United States
- Department of Electrical and Computer Engineering, Duke University, Durham, NC, United States
- Department of Neurobiology, Duke University, Durham, NC, United States
- Department of Neurosurgery, Duke University, Durham, NC, United States
| | - Nicole A. Pelot
- Department of Biomedical Engineering, Duke University, Durham, NC, United States
| | - Shigao Chen
- Department of Radiology, Mayo Clinic, Rochester, MN, United States
| | - Kip A. Ludwig
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States
- Wisconsin Institute of Neuroengineering (WITNe), University of Wisconsin-Madison, Madison, WI, United States
- Department of Neurosurgery, University of Wisconsin-Madison, Madison, WI, United States
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26
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Ahmed U, Chang YC, Lopez MF, Wong J, Datta-Chaudhuri T, Rieth L, Al-Abed Y, Zanos S. Implant- and anesthesia-related factors affecting cardiopulmonary threshold intensities for vagus nerve stimulation. J Neural Eng 2021; 18. [PMID: 34036940 DOI: 10.1088/1741-2552/ac048a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Accepted: 05/24/2021] [Indexed: 11/11/2022]
Abstract
Objective.Vagus nerve stimulation (VNS) is typically delivered at increasing stimulus intensity until a neurological or physiological response is observed ('threshold') for dose calibration, preclinically and therapeutically. Factors affecting VNS thresholds have not been studied systematically. In a rodent model of VNS we measured neural and physiological responses to increasing VNS intensity, determined neurological and physiological thresholds and examined the effect of implant- and anesthesia-related factors on thresholds.Approach.In acute and chronic vagus implants (45 and 20 rats, respectively) VNS was delivered under isoflurane, ketamine-xylazine, or awake conditions. Evoked compound action potentials (CAPs) were recorded and activation of different fiber types was extracted. Elicited physiological responses were registered, including changes in heart rate (HR), breathing rate (BR), and blood pressure (BP). CAP and physiological thresholds were determined.Main results. The threshold for evoking discernable CAPs (>10µV) (CAP threshold) is significantly lower than what elicits 5%-10% drop in heart rate (heart rate threshold, HRT) (25µA ± 1.8 vs. 80µA ± 5.1, respectively; mean ± SEM). Changes in BP and small changes in BR (bradypnea) occur at lowest intensities (70µA ± 8.3), followed by HR changes (80µA ± 5.1) and finally significant changes in BR (apnea) (310μA ± 32.5). HRT and electrode impedance are correlated in chronic (Pearson correlationr= 0.47;p< 0.001) but not in acute implants (r= -0.34;pNS); HRT and impedance both increase with implant age (r= 0.44;p< 0.001 andr= 0.64;p< 0.001, respectively). HRT is lowest when animals are awake (200µA ± 35.5), followed by ketamine-xylazine (640µA ± 151.5), and isoflurane (1000µA ± 139.5). The sequence of physiological responses with increasing VNS intensity is the same in anesthetized and awake animals. Pulsing frequency affects physiological responses but not CAPs.Significance. Implant age, electrode impedance, and type of anesthesia affect VNS thresholds and should be accounted for when calibrating stimulation dose.
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Affiliation(s)
- Umair Ahmed
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, 350 Community Drive, Manhasset, NY 11030, United States of America
| | - Yao-Chuan Chang
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, 350 Community Drive, Manhasset, NY 11030, United States of America
| | - Maria F Lopez
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, 350 Community Drive, Manhasset, NY 11030, United States of America
| | - Jason Wong
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, 350 Community Drive, Manhasset, NY 11030, United States of America
| | - Timir Datta-Chaudhuri
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, 350 Community Drive, Manhasset, NY 11030, United States of America
| | - Loren Rieth
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, 350 Community Drive, Manhasset, NY 11030, United States of America
| | - Yousef Al-Abed
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, 350 Community Drive, Manhasset, NY 11030, United States of America
| | - Stavros Zanos
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, 350 Community Drive, Manhasset, NY 11030, United States of America
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27
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Fitchett A, Mastitskaya S, Aristovich K. Selective Neuromodulation of the Vagus Nerve. Front Neurosci 2021; 15:685872. [PMID: 34108861 PMCID: PMC8180849 DOI: 10.3389/fnins.2021.685872] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 04/27/2021] [Indexed: 01/01/2023] Open
Abstract
Vagus nerve stimulation (VNS) is an effective technique for the treatment of refractory epilepsy and shows potential for the treatment of a range of other serious conditions. However, until now stimulation has generally been supramaximal and non-selective, resulting in a range of side effects. Selective VNS (sVNS) aims to mitigate this by targeting specific fiber types within the nerve to produce functionally specific effects. In recent years, several key paradigms of sVNS have been developed-spatially selective, fiber-selective, anodal block, neural titration, and kilohertz electrical stimulation block-as well as various stimulation pulse parameters and electrode array geometries. sVNS can significantly reduce the severity of side effects, and in some cases increase efficacy of the treatment. While most studies have focused on fiber-selective sVNS, spatially selective sVNS has demonstrated comparable mitigation of side-effects. It has the potential to achieve greater specificity and provide crucial information about vagal nerve physiology. Anodal block achieves strong side-effect mitigation too, but is much less specific than fiber- and spatially selective paradigms. The major hurdle to achieving better selectivity of VNS is a limited knowledge of functional anatomical organization of vagus nerve. It is also crucial to optimize electrode array geometry and pulse shape, as well as expand the applications of sVNS beyond the current focus on cardiovascular disease.
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Affiliation(s)
| | - Svetlana Mastitskaya
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Kirill Aristovich
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
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28
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Datta-Chaudhuri T, Zanos T, Chang EH, Olofsson PS, Bickel S, Bouton C, Grande D, Rieth L, Aranow C, Bloom O, Mehta AD, Civillico G, Stevens MM, Głowacki E, Bettinger C, Schüettler M, Puleo C, Rennaker R, Mohanta S, Carnevale D, Conde SV, Bonaz B, Chernoff D, Kapa S, Berggren M, Ludwig K, Zanos S, Miller L, Weber D, Yoshor D, Steinman L, Chavan SS, Pavlov VA, Al-Abed Y, Tracey KJ. The Fourth Bioelectronic Medicine Summit "Technology Targeting Molecular Mechanisms": current progress, challenges, and charting the future. Bioelectron Med 2021; 7:7. [PMID: 34024277 PMCID: PMC8142479 DOI: 10.1186/s42234-021-00068-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 04/04/2021] [Indexed: 02/06/2023] Open
Abstract
There is a broad and growing interest in Bioelectronic Medicine, a dynamic field that continues to generate new approaches in disease treatment. The fourth bioelectronic medicine summit "Technology targeting molecular mechanisms" took place on September 23 and 24, 2020. This virtual meeting was hosted by the Feinstein Institutes for Medical Research, Northwell Health. The summit called international attention to Bioelectronic Medicine as a platform for new developments in science, technology, and healthcare. The meeting was an arena for exchanging new ideas and seeding potential collaborations involving teams in academia and industry. The summit provided a forum for leaders in the field to discuss current progress, challenges, and future developments in Bioelectronic Medicine. The main topics discussed at the summit are outlined here.
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Affiliation(s)
| | - Theodoros Zanos
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY USA
| | - Eric H. Chang
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY USA
| | | | - Stephan Bickel
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY USA
| | - Chad Bouton
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY USA
| | - Daniel Grande
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY USA
| | - Loren Rieth
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY USA
- University of Utah, Salt Lake City, UT USA
| | - Cynthia Aranow
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY USA
| | - Ona Bloom
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY USA
| | - Ashesh D. Mehta
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY USA
| | | | | | | | | | | | | | | | - Saroj Mohanta
- Institute for Cardiovascular Prevention, Ludwig-Maximilians-University, Munich, Germany
| | - Daniela Carnevale
- Sapienza University of Rome, Rome, Italy
- IRCCS Neuromed, Pozzilli, Italy
| | - Silvia V. Conde
- CEDOC, Nova Medical School, Faculdade de Ciências Médicas, Lisbon, Portugal
| | - Bruno Bonaz
- University of Grenoble Alpes, INSERM, Grenoble, France
| | | | | | | | - Kip Ludwig
- University of Wisconsin, Madison, WI USA
| | - Stavros Zanos
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY USA
| | - Larry Miller
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY USA
| | - Doug Weber
- Carnegie Mellon University, Pittsburgh, PA USA
| | | | | | - Sangeeta S. Chavan
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY USA
| | - Valentin A. Pavlov
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY USA
| | - Yousef Al-Abed
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY USA
| | - Kevin J. Tracey
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY USA
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29
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Donegà M, Fjordbakk CT, Kirk J, Sokal DM, Gupta I, Hunsberger GE, Crawford A, Cook S, Viscasillas J, Stathopoulou TR, Miranda JA, Dopson WJ, Goodwin D, Rowles A, McGill P, McSloy A, Werling D, Witherington J, Chew DJ, Perkins JD. Human-relevant near-organ neuromodulation of the immune system via the splenic nerve. Proc Natl Acad Sci U S A 2021; 118:e2025428118. [PMID: 33972441 PMCID: PMC8157920 DOI: 10.1073/pnas.2025428118] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Neuromodulation of immune function by stimulating the autonomic connections to the spleen has been demonstrated in rodent models. Consequently, neuroimmune modulation has been proposed as a new therapeutic strategy for the treatment of inflammatory conditions. However, demonstration of the translation of these immunomodulatory mechanisms in anatomically and physiologically relevant models is still lacking. Additionally, translational models are required to identify stimulation parameters that can be transferred to clinical applications of bioelectronic medicines. Here, we performed neuroanatomical and functional comparison of the mouse, rat, pig, and human splenic nerve using in vivo and ex vivo preparations. The pig was identified as a more suitable model of the human splenic innervation. Using functional electrophysiology, we developed a clinically relevant marker of splenic nerve engagement through stimulation-dependent reversible reduction in local blood flow. Translation of immunomodulatory mechanisms were then assessed using pig splenocytes and two models of acute inflammation in anesthetized pigs. The pig splenic nerve was shown to locally release noradrenaline upon stimulation, which was able to modulate cytokine production by pig splenocytes. Splenic nerve stimulation was found to promote cardiovascular protection as well as cytokine modulation in a high- and a low-dose lipopolysaccharide model, respectively. Importantly, splenic nerve-induced cytokine modulation was reproduced by stimulating the efferent trunk of the cervical vagus nerve. This work demonstrates that immune responses can be modulated by stimulation of spleen-targeted autonomic nerves in translational species and identifies splenic nerve stimulation parameters and biomarkers that are directly applicable to humans due to anatomical and electrophysiological similarities.
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Affiliation(s)
- Matteo Donegà
- Translation and Engineering, Galvani Bioelectronics, Stevenage SG1 2NY, United Kingdom;
| | - Cathrine T Fjordbakk
- Clinical Sciences and Services, The Royal Veterinary College, Hatfield AL9 7TA, United Kingdom
| | - Joseph Kirk
- Clinical Sciences and Services, The Royal Veterinary College, Hatfield AL9 7TA, United Kingdom
| | - David M Sokal
- Translation and Engineering, Galvani Bioelectronics, Stevenage SG1 2NY, United Kingdom
| | - Isha Gupta
- Translation and Engineering, Galvani Bioelectronics, Stevenage SG1 2NY, United Kingdom
| | - Gerald E Hunsberger
- Translation and Engineering, Galvani Bioelectronics, Stevenage SG1 2NY, United Kingdom
| | - Abbe Crawford
- Clinical Sciences and Services, The Royal Veterinary College, Hatfield AL9 7TA, United Kingdom
| | - Simon Cook
- Clinical Sciences and Services, The Royal Veterinary College, Hatfield AL9 7TA, United Kingdom
| | - Jaime Viscasillas
- Clinical Sciences and Services, The Royal Veterinary College, Hatfield AL9 7TA, United Kingdom
| | | | - Jason A Miranda
- Translation and Engineering, Galvani Bioelectronics, Stevenage SG1 2NY, United Kingdom
| | - Wesley J Dopson
- Translation and Engineering, Galvani Bioelectronics, Stevenage SG1 2NY, United Kingdom
| | - David Goodwin
- Clinical Sciences and Services, The Royal Veterinary College, Hatfield AL9 7TA, United Kingdom
| | - Alison Rowles
- Non-Clinical Safety, GlaxoSmithKline, Ware SG12 0DP, United Kingdom
| | - Paul McGill
- Bioimaging, GlaxoSmithKline, Ware SG12 0DP, United Kingdom
| | - Alex McSloy
- Clinical Sciences and Services, The Royal Veterinary College, Hatfield AL9 7TA, United Kingdom
| | - Dirk Werling
- Department of Pathobiology and Population Sciences, Royal Veterinary College, Hatfield AL9 7TA, United Kingdom
| | - Jason Witherington
- Translation and Engineering, Galvani Bioelectronics, Stevenage SG1 2NY, United Kingdom
| | - Daniel J Chew
- Translation and Engineering, Galvani Bioelectronics, Stevenage SG1 2NY, United Kingdom
| | - Justin D Perkins
- Clinical Sciences and Services, The Royal Veterinary College, Hatfield AL9 7TA, United Kingdom;
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30
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Verma N, Mudge JD, Kasole M, Chen RC, Blanz SL, Trevathan JK, Lovett EG, Williams JC, Ludwig KA. Auricular Vagus Neuromodulation-A Systematic Review on Quality of Evidence and Clinical Effects. Front Neurosci 2021; 15:664740. [PMID: 33994937 PMCID: PMC8120162 DOI: 10.3389/fnins.2021.664740] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 03/25/2021] [Indexed: 12/13/2022] Open
Abstract
Background: The auricular branch of the vagus nerve runs superficially, which makes it a favorable target for non-invasive stimulation techniques to modulate vagal activity. For this reason, there have been many early-stage clinical trials on a diverse range of conditions. These trials often report conflicting results for the same indication. Methods: Using the Cochrane Risk of Bias tool we conducted a systematic review of auricular vagus nerve stimulation (aVNS) randomized controlled trials (RCTs) to identify the factors that led to these conflicting results. The majority of aVNS studies were assessed as having "some" or "high" risk of bias, which makes it difficult to interpret their results in a broader context. Results: There is evidence of a modest decrease in heart rate during higher stimulation dosages, sometimes at above the level of sensory discomfort. Findings on heart rate variability conflict between studies and are hindered by trial design, including inappropriate washout periods, and multiple methods used to quantify heart rate variability. There is early-stage evidence to suggest aVNS may reduce circulating levels and endotoxin-induced levels of inflammatory markers. Studies on epilepsy reached primary endpoints similar to previous RCTs testing implantable vagus nerve stimulation therapy. Preliminary evidence shows that aVNS ameliorated pathological pain but not evoked pain. Discussion: Based on results of the Cochrane analysis we list common improvements for the reporting of results, which can be implemented immediately to improve the quality of evidence. In the long term, existing data from aVNS studies and salient lessons from drug development highlight the need for direct measures of local neural target engagement. Direct measures of neural activity around the electrode will provide data for the optimization of electrode design, placement, and stimulation waveform parameters to improve on-target engagement and minimize off-target activation. Furthermore, direct measures of target engagement, along with consistent evaluation of blinding success, must be used to improve the design of controls-a major source of concern identified in the Cochrane analysis. The need for direct measures of neural target engagement and consistent evaluation of blinding success is applicable to the development of other paresthesia-inducing neuromodulation therapies and their control designs.
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Affiliation(s)
- Nishant Verma
- Department of Biomedical Engineering, University of Wisconsin – Madison, Madison, WI, United States
- Wisconsin Institute for Translational Neuroengineering (WITNe) – Madison, Madison, WI, United States
| | - Jonah D. Mudge
- Department of Biomedical Engineering, University of Wisconsin – Madison, Madison, WI, United States
- Wisconsin Institute for Translational Neuroengineering (WITNe) – Madison, Madison, WI, United States
| | - Maïsha Kasole
- Department of Biomedical Engineering, University of Wisconsin – Madison, Madison, WI, United States
- Wisconsin Institute for Translational Neuroengineering (WITNe) – Madison, Madison, WI, United States
| | - Rex C. Chen
- Department of Biomedical Engineering, University of Wisconsin – Madison, Madison, WI, United States
- Wisconsin Institute for Translational Neuroengineering (WITNe) – Madison, Madison, WI, United States
| | - Stephan L. Blanz
- Department of Biomedical Engineering, University of Wisconsin – Madison, Madison, WI, United States
- Wisconsin Institute for Translational Neuroengineering (WITNe) – Madison, Madison, WI, United States
| | - James K. Trevathan
- Department of Biomedical Engineering, University of Wisconsin – Madison, Madison, WI, United States
- Wisconsin Institute for Translational Neuroengineering (WITNe) – Madison, Madison, WI, United States
| | | | - Justin C. Williams
- Department of Biomedical Engineering, University of Wisconsin – Madison, Madison, WI, United States
- Wisconsin Institute for Translational Neuroengineering (WITNe) – Madison, Madison, WI, United States
- Department of Neurosurgery, University of Wisconsin – Madison, Madison, WI, United States
| | - Kip A. Ludwig
- Department of Biomedical Engineering, University of Wisconsin – Madison, Madison, WI, United States
- Wisconsin Institute for Translational Neuroengineering (WITNe) – Madison, Madison, WI, United States
- Department of Neurosurgery, University of Wisconsin – Madison, Madison, WI, United States
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31
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Abstract
Peripheral nerve interfaces (PNIs) record and/or modulate neural activity of nerves, which are responsible for conducting sensory-motor information to and from the central nervous system, and for regulating the activity of inner organs. PNIs are used both in neuroscience research and in therapeutical applications such as precise closed-loop control of neuroprosthetic limbs, treatment of neuropathic pain and restoration of vital functions (e.g. breathing and bladder management). Implantable interfaces represent an attractive solution to directly access peripheral nerves and provide enhanced selectivity both in recording and in stimulation, compared to their non-invasive counterparts. Nevertheless, the long-term functionality of implantable PNIs is limited by tissue damage, which occurs at the implant-tissue interface, and is thus highly dependent on material properties, biocompatibility and implant design. Current research focuses on the development of mechanically compliant PNIs, which adapt to the anatomy and dynamic movements of nerves in the body thereby limiting foreign body response. In this paper, we review recent progress in the development of flexible and implantable PNIs, highlighting promising solutions related to materials selection and their associated fabrication methods, and integrated functions. We report on the variety of available interface designs (intraneural, extraneural and regenerative) and different modulation techniques (electrical, optical, chemical) emphasizing the main challenges associated with integrating such systems on compliant substrates.
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Affiliation(s)
- Valentina Paggi
- Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronic Interfaces, Institute of Microengineering, Institute of Bioengineering, Centre for Neuroprosthetics, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1202 Geneva, Switzerland. Equally contributing authors
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32
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Kolluru C, Subramaniam A, Liu Y, Upadhye A, Khela M, Druschel L, Fereidouni F, Levenson R, Shoffstall A, Jenkins M, Wilson DL. 3D imaging of the vagus nerve fascicular anatomy with cryo-imaging and UV excitation. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2021; 11649:1164910. [PMID: 35313654 PMCID: PMC8934573 DOI: 10.1117/12.2577037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Vagus nerve stimulation (VNS) is a method to treat drug-resistant epilepsy and depression, but therapeutic outcomes are often not ideal. Newer electrode designs such as intra-fascicular electrodes offer potential improvements in reducing off-target effects but require a detailed understanding of the fascicular anatomy of the vagus nerve. We have adapted a section-and-image technique, cryo-imaging, with UV excitation to visualize fascicles along the length of the vagus nerve. In addition to offering optical sectioning at the surface via reduced penetration depth, UV illumination also produces sufficient contrast between fascicular structures and connective tissue. Here we demonstrate the utility of this approach in pilot experiments. We imaged fixed, cadaver vagus nerve samples, segmented fascicles, and demonstrated 3D tracking of fascicles. Such data can serve as input for computer models of vagus nerve stimulation.
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Affiliation(s)
- Chaitanya Kolluru
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Ananya Subramaniam
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Yehe Liu
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Aniruddha Upadhye
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Monty Khela
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Lindsey Druschel
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | | | | | - Andrew Shoffstall
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Michael Jenkins
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - David L. Wilson
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
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33
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Pelot NA, Goldhagen GB, Cariello JE, Musselman ED, Clissold KA, Ezzell JA, Grill WM. Quantified Morphology of the Cervical and Subdiaphragmatic Vagus Nerves of Human, Pig, and Rat. Front Neurosci 2020; 14:601479. [PMID: 33250710 PMCID: PMC7672126 DOI: 10.3389/fnins.2020.601479] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 10/13/2020] [Indexed: 12/27/2022] Open
Abstract
It is necessary to understand the morphology of the vagus nerve (VN) to design and deliver effective and selective vagus nerve stimulation (VNS) because nerve morphology influences fiber responses to electrical stimulation. Specifically, nerve diameter (and thus, electrode-fiber distance), fascicle diameter, fascicular organization, and perineurium thickness all significantly affect the responses of nerve fibers to electrical signals delivered through a cuff electrode. We quantified the morphology of cervical and subdiaphragmatic VNs in humans, pigs, and rats: effective nerve diameter, number of fascicles, effective fascicle diameters, proportions of endoneurial, perineurial, and epineurial tissues, and perineurium thickness. The human and pig VNs were comparable sizes (∼2 mm cervically; ∼1.6 mm subdiaphragmatically), while the rat nerves were ten times smaller. The pig nerves had ten times more fascicles-and the fascicles were smaller-than in human nerves (47 vs. 7 fascicles cervically; 38 vs. 5 fascicles subdiaphragmatically). Comparing the cervical to the subdiaphragmatic VNs, the nerves and fascicles were larger at the cervical level for all species and there were more fascicles for pigs. Human morphology generally exhibited greater variability across samples than pigs and rats. A prior study of human somatic nerves indicated that the ratio of perineurium thickness to fascicle diameter was approximately constant across fascicle diameters. However, our data found thicker human and pig VN perineurium than those prior data: the VNs had thicker perineurium for larger fascicles and thicker perineurium normalized by fascicle diameter for smaller fascicles. Understanding these differences in VN morphology between preclinical models and the clinical target, as well as the variability across individuals of a species, is essential for designing suitable cuff electrodes and stimulation parameters and for informing translation of preclinical results to clinical application to advance the therapeutic efficacy of VNS.
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Affiliation(s)
- Nicole A. Pelot
- Department of Biomedical Engineering, Duke University, Durham, NC, United States
| | - Gabriel B. Goldhagen
- Department of Biomedical Engineering, Duke University, Durham, NC, United States
| | - Jake E. Cariello
- Department of Biomedical Engineering, Duke University, Durham, NC, United States
| | - Eric D. Musselman
- Department of Biomedical Engineering, Duke University, Durham, NC, United States
| | - Kara A. Clissold
- Histology Research Core, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - J. Ashley Ezzell
- Histology Research Core, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Warren M. Grill
- Department of Biomedical Engineering, Duke University, Durham, NC, United States
- Department of Electrical and Computer Engineering, Duke University, Durham, NC, United States
- Department of Neurobiology, Duke University, Durham, NC, United States
- Department of Neurosurgery, School of Medicine, Duke University, Durham, NC, United States
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34
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Gurel NZ, Jiao Y, Wittbrodt MT, Ko YA, Hankus A, Driggers EG, Ladd SL, Shallenberger L, Murrah N, Huang M, Haffar A, Alkhalaf M, Levantsevych O, Nye JA, Vaccarino V, Shah AJ, Inan OT, Bremner JD, Pearce BD. Effect of transcutaneous cervical vagus nerve stimulation on the pituitary adenylate cyclase-activating polypeptide (PACAP) response to stress: A randomized, sham controlled, double blind pilot study. COMPREHENSIVE PSYCHONEUROENDOCRINOLOGY 2020; 4:100012. [PMID: 35755625 PMCID: PMC9216713 DOI: 10.1016/j.cpnec.2020.100012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 09/17/2020] [Accepted: 10/15/2020] [Indexed: 12/24/2022] Open
Abstract
Pituitary adenylate cyclase-activating peptide (PACAP) is a neuropeptide that plays a key role in the neurobiology of the stress response, and prior studies suggest that its function is dysregulated in post-traumatic stress disorder (PTSD). Transcutaneous cervical vagus nerve stimulation (tcVNS) acts through PACAP and other neurobiological systems to modulate stress responses and/or symptoms of PTSD. In this pilot study, we examined the effects of tcVNS on PACAP in a three day chronic stress laboratory paradigm involving serial traumatic and mental stress exposures in healthy individuals with a history of exposure to psychological trauma (n = 18) and patients with PTSD (n = 12). Methods A total of 30 subjects with a history of exposure to psychological trauma experience were recruited (12 with PTSD diagnosis) for a three-day randomized double-blinded study of tcVNS or sham stimulation. Subjects underwent a protocol that included both personalized trauma recall and non-personalized mental stressors (public speaking, mental arithmetic) paired to tcVNS or sham stimulation over three days. Blood was collected at baseline and multiple time points after exposure to stressors. Linear mixed-effects models were used to assess changes in PACAP over time (in response to stressors) and its relation to active tcVNS or sham stimulation. Results PACAP blood levels increased over the course of three days for both active tcVNS and sham groups. This increase was statistically-significant in the sham group at the end of the second (Cohen’s drm = 0.35, p = 0.04), and third days (drm = 0.41, p = 0.04), but not in the active tcVNS group (drm = 0.21, drm = 0.18, and p > 0.20). Conclusion These pilot findings suggest tcVNS may attenuate this neurobiological stress-response. Larger studies are needed to investigate gender and interaction effects. We examined the effects of tcVNS on PACAP in a three day chronic stress paradigm involving traumatic and mental stress. PACAP levels increased over the course of three days for both groups, the elevation of PACAP was larger in the sham group. These findings suggest that tcVNS may be a potential intervention for stress-related psychiatric disorders.
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Affiliation(s)
- Nil Z. Gurel
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Yunshen Jiao
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Matthew T. Wittbrodt
- Department of Psychiatry and Behavioral Sciences, Emory School of Medicine, Atlanta, GA, USA
| | - Yi-An Ko
- Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Allison Hankus
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Emily G. Driggers
- Department of Psychiatry and Behavioral Sciences, Emory School of Medicine, Atlanta, GA, USA
| | - Stacy L. Ladd
- Department of Psychiatry and Behavioral Sciences, Emory School of Medicine, Atlanta, GA, USA
- Department of Radiology, Emory School of Medicine, Atlanta, GA, USA
| | - Lucy Shallenberger
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Nancy Murrah
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Minxuan Huang
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Ammer Haffar
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Mhmtjamil Alkhalaf
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Oleksiy Levantsevych
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Jonathon A. Nye
- Department of Radiology, Emory School of Medicine, Atlanta, GA, USA
| | - Viola Vaccarino
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
- Department of Medicine, Division of Cardiology, Emory School of Medicine, Atlanta, GA, USA
| | - Amit J. Shah
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
- Department of Medicine, Division of Cardiology, Emory School of Medicine, Atlanta, GA, USA
- Atlanta VA Medical Center, Decatur, GA, USA
| | - Omer T. Inan
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA, USA
- Coulter Department of Bioengineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - J. Douglas Bremner
- Department of Psychiatry and Behavioral Sciences, Emory School of Medicine, Atlanta, GA, USA
- Department of Radiology, Emory School of Medicine, Atlanta, GA, USA
- Atlanta VA Medical Center, Decatur, GA, USA
| | - Bradley D. Pearce
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
- Corresponding author.
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Nicolai EN, Settell ML, Knudsen BE, McConico AL, Gosink BA, Trevathan JK, Baumgart IW, Ross EK, Pelot NA, Grill WM, Gustafson KJ, Shoffstall AJ, Williams JC, Ludwig KA. Sources of off-target effects of vagus nerve stimulation using the helical clinical lead in domestic pigs. J Neural Eng 2020; 17:046017. [PMID: 32554888 PMCID: PMC7717671 DOI: 10.1088/1741-2552/ab9db8] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Objective Clinical data suggest that efficacious vagus nerve stimulation (VNS) is limited by side effects such as cough and dyspnea that have stimulation thresholds lower than those for therapeutic outcomes. VNS side effects are putatively caused by activation of nearby muscles within the neck, via direct muscle activation or activation of nerve fibers innervating those muscles. Our goal was to determine the thresholds at which various VNS-evoked effects occur in the domestic pig—an animal model with vagus anatomy similar to human—using the bipolar helical lead deployed clinically. Approach Intrafascicular electrodes were placed within the vagus nerve to record electroneurographic (ENG) responses, and needle electrodes were placed in the vagal-innervated neck muscles to record electromyographic (EMG) responses. Main results Contraction of the cricoarytenoid muscle occurred at low amplitudes (~0.3 mA) and resulted from activation of motor nerve fibers in the cervical vagus trunk within the electrode cuff which bifurcate into the recurrent laryngeal branch of the vagus. At higher amplitudes (~1.4 mA), contraction of the cricoarytenoid and cricothyroid muscles was generated by current leakage outside the cuff to activate motor nerve fibers running within the nearby superior laryngeal branch of the vagus. Activation of these muscles generated artifacts in the ENG recordings that may be mistaken for compound action potentials representing slowly conducting Aδ-, B-, and C-fibers. Significance Our data resolve conflicting reports of the stimulation amplitudes required for C-fiber activation in large animal studies (>10 mA) and human studies (<250 μA). After removing muscle-generated artifacts, ENG signals with post-stimulus latencies consistent with Aδ- and B-fibers occurred in only a small subset of animals, and these signals had similar thresholds to those that caused bradycardia. By identifying specific neuroanatomical pathways that cause off-target effects and characterizing the stimulation dose-response curves for on- and off-target effects, we hope to guide interpretation and optimization of clinical VNS.
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Affiliation(s)
- Evan N Nicolai
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Mayo Clinic, Mayo Clinic Graduate School of Biomedical Sciences, Rochester, MN, United States of America
- Wisconsin Institute of Neuroengineering (WITNe), University of Wisconsin-Madison, WI, United States of America
| | - Megan L Settell
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Mayo Clinic, Mayo Clinic Graduate School of Biomedical Sciences, Rochester, MN, United States of America
- Wisconsin Institute of Neuroengineering (WITNe), University of Wisconsin-Madison, WI, United States of America
| | - Bruce E Knudsen
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Department of Neurosurgery, Mayo Clinic, Rochester, MN, United States of America
- Wisconsin Institute of Neuroengineering (WITNe), University of Wisconsin-Madison, WI, United States of America
| | - Andrea L McConico
- Department of Neurosurgery, Mayo Clinic, Rochester, MN, United States of America
| | - Brian A Gosink
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Department of Neurosurgery, University of Wisconsin-Madison, Madison, WI, United States of America
| | - James K Trevathan
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute of Neuroengineering (WITNe), University of Wisconsin-Madison, WI, United States of America
| | - Ian W Baumgart
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Erika K Ross
- Abbott Neuromodulation, Plano, TX, United States of America
| | - Nicole A Pelot
- Department of Biomedical Engineering, Duke University, Durham, NC, United States of America
| | - Warren M Grill
- Department of Biomedical Engineering, Duke University, Durham, NC, United States of America
| | - Kenneth J Gustafson
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States of America
- Louis Stokes Cleveland VA Medical Center, Cleveland, OH, United States of America
| | - Andrew J Shoffstall
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States of America
- Louis Stokes Cleveland VA Medical Center, Cleveland, OH, United States of America
| | - Justin C Williams
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Department of Neurosurgery, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute of Neuroengineering (WITNe), University of Wisconsin-Madison, WI, United States of America
| | - Kip A Ludwig
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Department of Neurosurgery, University of Wisconsin-Madison, Madison, WI, United States of America
- Wisconsin Institute of Neuroengineering (WITNe), University of Wisconsin-Madison, WI, United States of America
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36
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Settell ML, Pelot NA, Knudsen BE, Dingle AM, McConico AL, Nicolai EN, Trevathan JK, Ezzell JA, Ross EK, Gustafson KJ, Shoffstall AJ, Williams JC, Zeng W, Poore SO, Populin LC, Suminski AJ, Grill WM, Ludwig KA. Functional vagotopy in the cervical vagus nerve of the domestic pig: implications for the study of vagus nerve stimulation. J Neural Eng 2020; 17:026022. [PMID: 32108590 PMCID: PMC7306215 DOI: 10.1088/1741-2552/ab7ad4] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
OBJECTIVE Given current clinical interest in vagus nerve stimulation (VNS), there are surprisingly few studies characterizing the anatomy of the vagus nerve in large animal models as it pertains to on-and off-target engagement of local fibers. We sought to address this gap by evaluating vagal anatomy in the pig, whose vagus nerve organization and size approximates the human vagus nerve. APPROACH Here we combined microdissection, histology, and immunohistochemistry to provide data on key features across the cervical vagus nerve in a swine model, and compare our results to other animal models (mouse, rat, dog, non-human primate) and humans. MAIN RESULTS In a swine model we quantified the nerve diameter, number and diameter of fascicles, and distance of fascicles from the epineural surface where stimulating electrodes are placed. We also characterized the relative locations of the superior and recurrent laryngeal branches of the vagus nerve that have been implicated in therapy limiting side effects with common electrode placement. We identified key variants across the cohort that may be important for VNS with respect to changing sympathetic/parasympathetic tone, such as cross-connections to the sympathetic trunk. We discovered that cell bodies of pseudo-unipolar cells aggregate together to form a very distinct grouping within the nodose ganglion. This distinct grouping gives rise to a larger number of smaller fascicles as one moves caudally down the vagus nerve. This often leads to a distinct bimodal organization, or 'vagotopy'. This vagotopy was supported by immunohistochemistry where approximately half of the fascicles were immunoreactive for choline acetyltransferase, and reactive fascicles were generally grouped in one half of the nerve. SIGNIFICANCE The vagotopy observed via histology may be advantageous to exploit in design of electrodes/stimulation paradigms. We also placed our data in context of historic and recent histology spanning multiple models, thus providing a comprehensive resource to understand similarities and differences across species.
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Affiliation(s)
- Megan L Settell
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Mayo Clinic, Mayo Clinic Graduate School of Biomedical Sciences, Rochester, MN, United States of America
| | - Nicole A Pelot
- Department of Biomedical Engineering, Duke University, Durham, NC, United States of America
| | - Bruce E Knudsen
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, United States of America
| | - Aaron M Dingle
- Division of Plastic Surgery, Department of Surgery, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Andrea L McConico
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, United States of America
| | - Evan N Nicolai
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Mayo Clinic, Mayo Clinic Graduate School of Biomedical Sciences, Rochester, MN, United States of America
| | - James K Trevathan
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Mayo Clinic, Mayo Clinic Graduate School of Biomedical Sciences, Rochester, MN, United States of America
| | - J Ashley Ezzell
- Histology Research Core, University of North Carolina School of Medicine, Durham, NC, United States of America
- Department of Cell Biology and Physiology, University of North Carolina School of Medicine, Durham, NC, United States of America
| | - Erika K Ross
- Abbott Neuromodulation, Plano, TX, United States of America
| | - Kenneth J Gustafson
- Department of Biomedical Engineering, Western Reserve University, Cleveland, OH, United States of America
- Louis Stokes Cleveland VA Medical Center, Cleveland, OH, United States of America
| | - Andrew J Shoffstall
- Department of Biomedical Engineering, Western Reserve University, Cleveland, OH, United States of America
- Louis Stokes Cleveland VA Medical Center, Cleveland, OH, United States of America
| | - Justin C Williams
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Department of Neurosurgery, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Weifeng Zeng
- Division of Plastic Surgery, Department of Surgery, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Samuel O Poore
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Division of Plastic Surgery, Department of Surgery, University of Wisconsin-Madison, Madison, WI, United States of America
- Department of Surgery, University of Wisconsin-Madison, Madison, WI, United States of America
- University of Wisconsin School of Medicine and Public Health, Madison, WI, United States of America
| | - Luis C Populin
- Department of Neuroscience, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Aaron J Suminski
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Department of Neurosurgery, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Warren M Grill
- Department of Biomedical Engineering, Duke University, Durham, NC, United States of America
- Department of Electrical and Computer Engineering, Duke University, Durham, NC, United States of America
- Department of Neurobiology, Duke University, Durham, NC, United States of America
- Department of Neurosurgery, Duke University, Durham, NC, United States of America
| | - Kip A Ludwig
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States of America
- Department of Neurosurgery, University of Wisconsin-Madison, Madison, WI, United States of America
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