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Löscher W, Worrell GA. Novel subscalp and intracranial devices to wirelessly record and analyze continuous EEG in unsedated, behaving dogs in their natural environments: A new paradigm in canine epilepsy research. Front Vet Sci 2022; 9:1014269. [PMID: 36337210 PMCID: PMC9631025 DOI: 10.3389/fvets.2022.1014269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 09/26/2022] [Indexed: 11/25/2022] Open
Abstract
Epilepsy is characterized by unprovoked, recurrent seizures and is a common neurologic disorder in dogs and humans. Roughly 1/3 of canines and humans with epilepsy prove to be drug-resistant and continue to have sporadic seizures despite taking daily anti-seizure medications. The optimization of pharmacologic therapy is often limited by inaccurate seizure diaries and medication side effects. Electroencephalography (EEG) has long been a cornerstone of diagnosis and classification in human epilepsy, but because of several technical challenges has played a smaller clinical role in canine epilepsy. The interictal (between seizures) and ictal (seizure) EEG recorded from the epileptic mammalian brain shows characteristic electrophysiologic biomarkers that are very useful for clinical management. A fundamental engineering gap for both humans and canines with epilepsy has been the challenge of obtaining continuous long-term EEG in the patients' natural environment. We are now on the cusp of a revolution where continuous long-term EEG from behaving canines and humans will be available to guide clinicians in the diagnosis and optimal treatment of their patients. Here we review some of the devices that have recently emerged for obtaining long-term EEG in ambulatory subjects living in their natural environments.
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Affiliation(s)
- Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hanover, Germany
- Center for Systems Neuroscience, Hanover, Germany
- *Correspondence: Wolfgang Löscher
| | - Gregory A. Worrell
- Bioelectronics Neurophysiology and Engineering Laboratory, Department of Neurology, Mayo Clinic, Rochester, MN, United States
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, United States
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2
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Deep brain electrophysiology in freely moving sheep. Curr Biol 2022; 32:763-774.e4. [PMID: 35030329 DOI: 10.1016/j.cub.2021.12.035] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Revised: 11/05/2021] [Accepted: 12/14/2021] [Indexed: 12/17/2022]
Abstract
Although rodents are arguably the easiest animals to use for studying brain function, relying on them as model species for translational research comes with its own set of limitations. Here, we propose sheep as a practical large animal species to use for in vivo brain function studies performed in naturalistic settings. We conducted proof-of-principle deep brain electrophysiological recording experiments using unrestrained sheep during behavioral testing. Recordings were made from cortex and hippocampus, both while sheep performed goal-directed behaviors (two-choice discrimination tasks) and across states of vigilance, including sleep. Hippocampal and cortical oscillatory rhythms were consistent with those seen in rodents and non-human primates, and included cortical alpha oscillations and hippocampal sharp wave ripple oscillations (∼150 Hz) during immobility and hippocampal theta oscillations (5-6 Hz) during locomotion. Recordings were conducted over a period of many months during which time the animals participated willingly in the experiments. Over 3,000 putative neurons were identified, including examples whose activity was modulated by task, speed of locomotion, spatial position, reward and vigilance states, and one whose firing rate was potentially modulated by the sight of the investigator. Together, these experiments demonstrate that sheep are excellent experimental animals to use for longitudinal studies requiring a large-brained mammal and/or large-scale recordings across distributed neuronal networks. Sheep could be used safely for studying not only neural encoding of decision-making and spatial-mapping in naturalistic environments outside the confines of the traditional laboratory but also the neural basis of both intra- and inter-species social interactions.
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Schalk G, Worrell S, Mivalt F, Belsten A, Kim I, Morris JM, Hermes D, Klassen BT, Staff NP, Messina S, Kaufmann T, Rickert J, Brunner P, Worrell GA, Miller KJ. Toward a fully implantable ecosystem for adaptive neuromodulation in humans: Preliminary experience with the CorTec BrainInterchange device in a canine model. Front Neurosci 2022; 16:932782. [PMID: 36601593 PMCID: PMC9806357 DOI: 10.3389/fnins.2022.932782] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 10/24/2022] [Indexed: 12/23/2022] Open
Abstract
This article describes initial work toward an ecosystem for adaptive neuromodulation in humans by documenting the experience of implanting CorTec's BrainInterchange (BIC) device in a beagle canine and using the BCI2000 environment to interact with the BIC device. It begins with laying out the substantial opportunity presented by a useful, easy-to-use, and widely available hardware/software ecosystem in the current landscape of the field of adaptive neuromodulation, and then describes experience with implantation, software integration, and post-surgical validation of recording of brain signals and implant parameters. Initial experience suggests that the hardware capabilities of the BIC device are fully supported by BCI2000, and that the BIC/BCI2000 device can record and process brain signals during free behavior. With further development and validation, the BIC/BCI2000 ecosystem could become an important tool for research into new adaptive neuromodulation protocols in humans.
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Affiliation(s)
- Gerwin Schalk
- Department of Neurosurgery, Mayo Clinic, Rochester, MN, United States
- Chen Frontier Lab for Applied Neurotechnology, Tianqiao and Chrissy Chen Institute, Shanghai, China
- *Correspondence: Gerwin Schalk
| | - Samuel Worrell
- Department of Neurosurgery, Mayo Clinic, Rochester, MN, United States
| | - Filip Mivalt
- Department of Neurology, Mayo Clinic, Rochester, MN, United States
- Department of Biomedical Engineering, Brno University of Technology, Brno, Czechia
| | - Alexander Belsten
- Department of Neurosurgery, Washington University in St. Louis, St. Louis, MO, United States
- National Center for Adaptive Neurotechnologies, Albany, NY, United States
| | - Inyong Kim
- Department of Neurology, Mayo Clinic, Rochester, MN, United States
| | | | - Dora Hermes
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, United States
| | - Bryan T. Klassen
- Department of Neurology, Mayo Clinic, Rochester, MN, United States
| | - Nathan P. Staff
- Department of Neurology, Mayo Clinic, Rochester, MN, United States
| | - Steven Messina
- Department of Neuroradiology, Mayo Clinic, Rochester, MN, United States
| | - Timothy Kaufmann
- Department of Neuroradiology, Mayo Clinic, Rochester, MN, United States
| | | | - Peter Brunner
- Department of Neurosurgery, Washington University in St. Louis, St. Louis, MO, United States
- National Center for Adaptive Neurotechnologies, Albany, NY, United States
| | - Gregory A. Worrell
- Department of Neurology, Mayo Clinic, Rochester, MN, United States
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, United States
| | - Kai J. Miller
- Department of Neurosurgery, Mayo Clinic, Rochester, MN, United States
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, United States
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Olutoye OA, Style C, Menchaca A. Neurocognitive Effects of Fetal Exposure to Anesthesia. Anesthesiol Clin 2021; 39:851-869. [PMID: 34776113 DOI: 10.1016/j.anclin.2021.08.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Surgery during pregnancy occurs when maternal or fetal needs outweigh the status quo, yet much uncertainty remains regarding the effects of anesthesia and surgery on fetal neurodevelopment. This article will review common maternal and fetal indications for invasive procedures, along with contemporary research on fetal neurodevelopment following anesthesia and surgery, focusing on future areas of investigation.
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Affiliation(s)
- Olutoyin A Olutoye
- Department of Anesthesiology, Perioperative and Pain Medicine, Texas Children's Hospital, Baylor College of Medicine, 6621 Fannin Street, Suite A-3300, Houston, TX 77030, USA.
| | - Candace Style
- Abigail Wexner Research Institute, Center for Regenerative Medicine, Nationwide Children's Hospital, 575 Children's Crossroad, Columbus, OH 43205, USA
| | - Alicia Menchaca
- Abigail Wexner Research Institute, Center for Regenerative Medicine, Nationwide Children's Hospital, 575 Children's Crossroad, Columbus, OH 43205, USA
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5
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Sahasrabuddhe K, Khan AA, Singh AP, Stern TM, Ng Y, Tadić A, Orel P, LaReau C, Pouzzner D, Nishimura K, Boergens KM, Shivakumar S, Hopper MS, Kerr B, Hanna MES, Edgington RJ, McNamara I, Fell D, Gao P, Babaie-Fishani A, Veijalainen S, Klekachev AV, Stuckey AM, Luyssaert B, Kozai TDY, Xie C, Gilja V, Dierickx B, Kong Y, Straka M, Sohal HS, Angle MR. The Argo: a high channel count recording system for neural recording in vivo. J Neural Eng 2021; 18:015002. [PMID: 33624614 PMCID: PMC8607496 DOI: 10.1088/1741-2552/abd0ce] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Decoding neural activity has been limited by the lack of tools available to record from large numbers of neurons across multiple cortical regions simultaneously with high temporal fidelity. To this end, we developed the Argo system to record cortical neural activity at high data rates. APPROACH Here we demonstrate a massively parallel neural recording system based on platinum-iridium microwire electrode arrays bonded to a CMOS voltage amplifier array. The Argo system is the highest channel count in vivo neural recording system, supporting simultaneous recording from 65 536 channels, sampled at 32 kHz and 12-bit resolution. This system was designed for cortical recordings, compatible with both penetrating and surface microelectrodes. MAIN RESULTS We validated this system through initial bench testing to determine specific gain and noise characteristics of bonded microwires, followed by in-vivo experiments in both rat and sheep cortex. We recorded spiking activity from 791 neurons in rats and surface local field potential activity from over 30 000 channels in sheep. SIGNIFICANCE These are the largest channel count microwire-based recordings in both rat and sheep. While currently adapted for head-fixed recording, the microwire-CMOS architecture is well suited for clinical translation. Thus, this demonstration helps pave the way for a future high data rate intracortical implant.
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Affiliation(s)
| | - Aamir A Khan
- Paradromics, Inc, Austin, TX, United States of America
| | | | - Tyler M Stern
- Paradromics, Inc, Austin, TX, United States of America
| | - Yeena Ng
- Paradromics, Inc, Austin, TX, United States of America
| | | | - Peter Orel
- Paradromics, Inc, Austin, TX, United States of America
| | - Chris LaReau
- Paradromics, Inc, Austin, TX, United States of America
| | | | | | | | | | | | - Bryan Kerr
- Paradromics, Inc, Austin, TX, United States of America
| | | | | | | | - Devin Fell
- Paradromics, Inc, Austin, TX, United States of America
| | - Peng Gao
- Caeleste CVBA, Mechelen, Belgium
| | | | | | | | | | | | - Takashi D Y Kozai
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States of America
- Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA, United States of America
- McGowan Institute of Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, United States of America
- NeuroTech Center, University of Pittsburgh Brain Institute, Pittsburgh, PA, United States of America
| | - Chong Xie
- Department of Electrical and Computer Engineering, Rice University, Houston, TX, United States of America
- Department of Bioengineering, Rice University, Houston, TX, United States of America
- NeuroEngineering Initiative, Rice University, Houston, TX, United States of America
| | - Vikash Gilja
- Department of Electrical and Computer Engineering, University of California, San Diego, La Jolla, CA, United States of America
| | | | - Yifan Kong
- Paradromics, Inc, Austin, TX, United States of America
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6
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Zaer H, Deshmukh A, Orlowski D, Fan W, Prouvot PH, Glud AN, Jensen MB, Worm ES, Lukacova S, Mikkelsen TW, Fitting LM, Adler JR, Schneider MB, Jensen MS, Fu Q, Go V, Morizio J, Sørensen JCH, Stroh A. An Intracortical Implantable Brain-Computer Interface for Telemetric Real-Time Recording and Manipulation of Neuronal Circuits for Closed-Loop Intervention. Front Hum Neurosci 2021; 15:618626. [PMID: 33613212 PMCID: PMC7887289 DOI: 10.3389/fnhum.2021.618626] [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: 10/17/2020] [Accepted: 01/14/2021] [Indexed: 11/13/2022] Open
Abstract
Recording and manipulating neuronal ensemble activity is a key requirement in advanced neuromodulatory and behavior studies. Devices capable of both recording and manipulating neuronal activity brain-computer interfaces (BCIs) should ideally operate un-tethered and allow chronic longitudinal manipulations in the freely moving animal. In this study, we designed a new intracortical BCI feasible of telemetric recording and stimulating local gray and white matter of visual neural circuit after irradiation exposure. To increase the translational reliance, we put forward a Göttingen minipig model. The animal was stereotactically irradiated at the level of the visual cortex upon defining the target by a fused cerebral MRI and CT scan. A fully implantable neural telemetry system consisting of a 64 channel intracortical multielectrode array, a telemetry capsule, and an inductive rechargeable battery was then implanted into the visual cortex to record and manipulate local field potentials, and multi-unit activity. We achieved a 3-month stability of the functionality of the un-tethered BCI in terms of telemetric radio-communication, inductive battery charging, and device biocompatibility for 3 months. Finally, we could reliably record the local signature of sub- and suprathreshold neuronal activity in the visual cortex with high bandwidth without complications. The ability to wireless induction charging combined with the entirely implantable design, the rather high recording bandwidth, and the ability to record and stimulate simultaneously put forward a wireless BCI capable of long-term un-tethered real-time communication for causal preclinical circuit-based closed-loop interventions.
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Affiliation(s)
- Hamed Zaer
- Department of Neurosurgery, Center for Experimental Neuroscience (CENSE), Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Ashlesha Deshmukh
- Department of Electrical and Computer Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Dariusz Orlowski
- Department of Neurosurgery, Center for Experimental Neuroscience (CENSE), Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Wei Fan
- Leibniz Institute for Resilience Research, Mainz, Germany
| | | | - Andreas Nørgaard Glud
- Department of Neurosurgery, Center for Experimental Neuroscience (CENSE), Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Morten Bjørn Jensen
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Department of Oncology, Radiation Therapy, and Clinical Medicine, Aarhus University Hospital, Aarhus University, Aarhus, Denmark
| | - Esben Schjødt Worm
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Department of Oncology, Radiation Therapy, and Clinical Medicine, Aarhus University Hospital, Aarhus University, Aarhus, Denmark
| | - Slávka Lukacova
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Department of Oncology, Radiation Therapy, and Clinical Medicine, Aarhus University Hospital, Aarhus University, Aarhus, Denmark
| | - Trine Werenberg Mikkelsen
- Department of Neurosurgery, Center for Experimental Neuroscience (CENSE), Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Lise Moberg Fitting
- Department of Neurosurgery, Center for Experimental Neuroscience (CENSE), Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - John R. Adler
- Zap Surgical Systems, Inc., San Carlos, CA, United States
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA, United States
| | - M. Bret Schneider
- Zap Surgical Systems, Inc., San Carlos, CA, United States
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA, United States
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA, United States
| | - Martin Snejbjerg Jensen
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Department of Nuclear Medicine and PET Center, Institute of Clinical Medicine, Aarhus University and Hospital, Aarhus, Denmark
| | - Quanhai Fu
- Department of Electrical and Computer Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Vinson Go
- Department of Electrical and Computer Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - James Morizio
- Department of Electrical and Computer Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Jens Christian Hedemann Sørensen
- Department of Neurosurgery, Center for Experimental Neuroscience (CENSE), Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Albrecht Stroh
- Leibniz Institute for Resilience Research, Mainz, Germany
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
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7
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Erhardt JB, Lottner T, Pasluosta CF, Gessner I, Mathur S, Schuettler M, Bock M, Stieglitz T. Fabrication and validation of reference structures for the localization of subdural standard- and micro-electrodes in MRI. J Neural Eng 2020; 17:046044. [PMID: 32764195 DOI: 10.1088/1741-2552/abad7a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE Report simple reference structure fabrication and validate the precise localization of subdural micro- and standard electrodes in magnetic resonance imaging (MRI) in phantom experiments. APPROACH Electrode contacts with diameters of 0.3 mm and 4 mm are localized in 1.5 T MRI using reference structures made of silicone and iron oxide nanoparticle doping. The precision of the localization procedure was assessed for several standard MRI sequences and implant orientations in phantom experiments and compared to common clinical localization procedures. MAIN RESULTS A localization precision of 0.41 ± 0.20 mm could be achieved for both electrode diameters compared to 1.46 ± 0.69 mm that was achieved for 4 mm standard electrode contacts localized using a common clinical standard method. The new reference structures are intrinsically bio-compatible, and they can be detected with currently available feature detection software so that a clinical implementation of this technology should be feasible. SIGNIFICANCE Neuropathologies are increasingly diagnosed and treated with subdural electrodes, where the exact localization of the electrode contacts with respect to the patient's cortical anatomy is a prerequisite for the procedure. Post-implantation electrode localization using MRI may be advantageous compared to the common alternative of CT-MRI image co-registration, as it avoids systematic localization errors associated with the co-registration itself, as well as brain shift and implant movement. Additionally, MRI provides superior soft tissue contrast for the identification of brain lesions without exposing the patient to ionizing radiation. Recent studies show that smaller electrodes and high-density electrode grids are ideal for clinical and research purposes, but the localization of these devices in MRI has not been demonstrated.
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Affiliation(s)
- Johannes B Erhardt
- Department of Microsystems Engineering-IMTEK, University of Freiburg, Freiburg, Germany. BrainLinks-BrainTools, Freiburg, Germany
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Cutrone A, Micera S. Implantable Neural Interfaces and Wearable Tactile Systems for Bidirectional Neuroprosthetics Systems. Adv Healthc Mater 2019; 8:e1801345. [PMID: 31763784 DOI: 10.1002/adhm.201801345] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 03/22/2019] [Indexed: 12/12/2022]
Abstract
Neuroprosthetics and neuromodulation represent a promising field for several related applications in the central and peripheral nervous system, such as the treatment of neurological disorders, the control of external robotic devices, and the restoration of lost tactile functions. These actions are allowed by the neural interface, a miniaturized implantable device that most commonly exploits electrical energy to fulfill these operations. A neural interface must be biocompatible, stable over time, low invasive, and highly selective; the challenge is to develop a safe, compact, and reliable tool for clinical applications. In case of anatomical impairments, neuroprosthetics is bound to the need of exploring the surrounding environment by fast-responsive and highly sensitive artificial tactile sensors that mimic the natural sense of touch. Tactile sensors and neural interfaces are closely interconnected since the readouts from the first are required to convey information to the neural implantable apparatus. The role of these devices is pivotal hence technical improvements are essential to ensure a secure system to be eventually adopted in daily life. This review highlights the fundamental criteria for the design and microfabrication of neural interfaces and artificial tactile sensors, their use in clinical applications, and future enhancements for the release of a second generation of devices.
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Affiliation(s)
- Annarita Cutrone
- The Biorobotics Institute, Viale Rinaldo Piaggio 34, 56025, Pontedera, Italy
| | - Silvestro Micera
- The Biorobotics Institute, Viale Rinaldo Piaggio 34, 56025, Pontedera, Italy
- Bertarelli Foundation Chair in Translational Neuroengineering, Centre for Neuroprosthetics and Institute of Bioengineering, School of Engineering, Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne, CH-1202, Switzerland
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9
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Pieri V, Trovatelli M, Cadioli M, Zani DD, Brizzola S, Ravasio G, Acocella F, Di Giancamillo M, Malfassi L, Dolera M, Riva M, Bello L, Falini A, Castellano A. In vivo Diffusion Tensor Magnetic Resonance Tractography of the Sheep Brain: An Atlas of the Ovine White Matter Fiber Bundles. Front Vet Sci 2019; 6:345. [PMID: 31681805 PMCID: PMC6805705 DOI: 10.3389/fvets.2019.00345] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 09/24/2019] [Indexed: 11/30/2022] Open
Abstract
Diffusion Tensor Magnetic Resonance Imaging (DTI) allows to decode the mobility of water molecules in cerebral tissue, which is highly directional along myelinated fibers. By integrating the direction of highest water diffusion through the tissue, DTI Tractography enables a non-invasive dissection of brain fiber bundles. As such, this technique is a unique probe for in vivo characterization of white matter architecture. Unraveling the principal brain texture features of preclinical models that are advantageously exploited in experimental neuroscience is crucial to correctly evaluate investigational findings and to correlate them with real clinical scenarios. Although structurally similar to the human brain, the gyrencephalic ovine model has not yet been characterized by a systematic DTI study. Here we present the first in vivo sheep (ovis aries) tractography atlas, where the course of the main white matter fiber bundles of the ovine brain has been reconstructed. In the context of the EU's Horizon EDEN2020 project, in vivo brain MRI protocol for ovine animal models was optimized on a 1.5T scanner. High resolution conventional MRI scans and DTI sequences (b-value = 1,000 s/mm2, 15 directions) were acquired on ten anesthetized sheep o. aries, in order to define the diffusion features of normal adult ovine brain tissue. Topography of the ovine cortex was studied and DTI maps were derived, to perform DTI tractography reconstruction of the corticospinal tract, corpus callosum, fornix, visual pathway, and occipitofrontal fascicle, bilaterally for all the animals. Binary masks of the tracts were then coregistered and reported in the space of a standard stereotaxic ovine reference system, to demonstrate the consistency of the fiber bundles and the minimal inter-subject variability in a unique tractography atlas. Our results determine the feasibility of a protocol to perform in vivo DTI tractography of the sheep, providing a reliable reconstruction and 3D rendering of major ovine fiber tracts underlying different neurological functions. Estimation of fiber directions and interactions would lead to a more comprehensive understanding of the sheep's brain anatomy, potentially exploitable in preclinical experiments, thus representing a precious tool for veterinaries and researchers.
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Affiliation(s)
- Valentina Pieri
- Neuroradiology Unit and CERMAC, Vita-Salute San Raffaele University, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Marco Trovatelli
- Department of Health, Animal Science and Food Safety, Faculty of Veterinary Medicine, University of Milan, Milan, Italy
| | | | - Davide Danilo Zani
- Department of Veterinary Medicine, Università degli Studi di Milano, Milan, Italy
| | - Stefano Brizzola
- Department of Veterinary Medicine, Università degli Studi di Milano, Milan, Italy
| | - Giuliano Ravasio
- Department of Veterinary Medicine, Università degli Studi di Milano, Milan, Italy
| | - Fabio Acocella
- Department of Health, Animal Science and Food Safety, Faculty of Veterinary Medicine, University of Milan, Milan, Italy
| | - Mauro Di Giancamillo
- Department of Veterinary Medicine, Università degli Studi di Milano, Milan, Italy
| | - Luca Malfassi
- Fondazione La Cittadina Studi e Ricerche Veterinarie, Romanengo, Italy
| | - Mario Dolera
- Fondazione La Cittadina Studi e Ricerche Veterinarie, Romanengo, Italy
| | - Marco Riva
- Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy.,Neurosurgical Oncology Unit, Humanitas Clinical and Research Center - IRCCS, Rozzano, Italy
| | - Lorenzo Bello
- Neurosurgical Oncology Unit, Humanitas Clinical and Research Center - IRCCS, Rozzano, Italy.,Department of Oncology and Hemato-Oncology, Università degli Studi di Milano, Milan, Italy
| | - Andrea Falini
- Neuroradiology Unit and CERMAC, Vita-Salute San Raffaele University, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Antonella Castellano
- Neuroradiology Unit and CERMAC, Vita-Salute San Raffaele University, IRCCS San Raffaele Scientific Institute, Milan, Italy
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10
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Sauter-Starace F, Ratel D, Cretallaz C, Foerster M, Lambert A, Gaude C, Costecalde T, Bonnet S, Charvet G, Aksenova T, Mestais C, Benabid AL, Torres-Martinez N. Long-Term Sheep Implantation of WIMAGINE ®, a Wireless 64-Channel Electrocorticogram Recorder. Front Neurosci 2019; 13:847. [PMID: 31496929 PMCID: PMC6712079 DOI: 10.3389/fnins.2019.00847] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 07/30/2019] [Indexed: 11/23/2022] Open
Abstract
This article deals with the long-term preclinical validation of WIMAGINE® (Wireless Implantable Multi-channel Acquisition system for Generic Interface with Neurons), a 64-channel wireless implantable recorder that measures the electrical activity at the cortical surface (electrocorticography, ECoG). The WIMAGINE® implant was designed for chronic wireless neuronal signal acquisition, to be used e.g., as an intracranial Brain–Computer Interface (BCI) for severely motor-impaired patients. Due to the size and shape of WIMAGINE®, sheep appeared to be the best animal model on which to carry out long-term in vivo validation. The devices were implanted in two sheep for a follow-up period of 10 months, including idle state cortical recordings and Somato-Sensory Evoked Potential (SSEP) sessions. ECoG and SSEP demonstrated relatively stable behavior during the 10-month observation period. Information recorded from the SensoriMotor Cortex (SMC) showed an SSEP phase reversal, indicating the cortical site of the sensorimotor activity was retained after 10 months of contact. Based on weekly recordings of raw ECoG signals, the effective bandwidth was in the range of 230 Hz for both animals and remarkably stable over time, meaning preservation of the high frequency bands valuable for decoding of the brain activity using BCIs. The power spectral density (in dB/Hz), on a log scale, was of the order of 2.2, –4.5 and –18 for the frequency bands (10–40), (40–100), and (100–200) Hz, respectively. The outcome of this preclinical work is the first long-term in vivo validation of the WIMAGINE® implant, highlighting its ability to record the brain electrical activity through the dura mater and to send wireless digitized data to the external base station. Apart from local adhesion of the dura to the skull, the neurosurgeon did not face any difficulty in the implantation of the WIMAGINE® device and post-mortem analysis of the brain revealed no side effect related to the implantation. We also report on the reliability of the system; including the implantable device, the antennas module and the external base station.
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Affiliation(s)
| | - D Ratel
- Univ. Grenoble Alpes, CEA, Leti, CLINATEC, Grenoble, France
| | - C Cretallaz
- Univ. Grenoble Alpes, CEA, Leti, CLINATEC, Grenoble, France
| | - M Foerster
- Univ. Grenoble Alpes, CEA, Leti, CLINATEC, Grenoble, France
| | - A Lambert
- Univ. Grenoble Alpes, CEA, Leti, CLINATEC, Grenoble, France
| | - C Gaude
- Univ. Grenoble Alpes, CEA, Leti, CLINATEC, Grenoble, France
| | - T Costecalde
- Univ. Grenoble Alpes, CEA, Leti, CLINATEC, Grenoble, France
| | - S Bonnet
- Univ. Grenoble Alpes, CEA, Leti, DTBS, Grenoble, France
| | - G Charvet
- Univ. Grenoble Alpes, CEA, Leti, CLINATEC, Grenoble, France
| | - T Aksenova
- Univ. Grenoble Alpes, CEA, Leti, CLINATEC, Grenoble, France
| | - C Mestais
- Univ. Grenoble Alpes, CEA, Leti, CLINATEC, Grenoble, France
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11
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Ella A, Barrière DA, Adriaensen H, Palmer DN, Melzer TR, Mitchell NL, Keller M. The development of brain magnetic resonance approaches in large animal models for preclinical research. Anim Front 2019; 9:44-51. [PMID: 32002261 PMCID: PMC6951960 DOI: 10.1093/af/vfz024] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Affiliation(s)
- Arsène Ella
- Physiologie de la Reproduction & des Comportements, INRA/CNRS/Université de Tours, France.,MRC Cognition and Brain Science Unit, University of Cambridge, UK
| | - David A Barrière
- Physiologie de la Reproduction & des Comportements, INRA/CNRS/Université de Tours, France.,Neurospin, CEA, France
| | - Hans Adriaensen
- Physiologie de la Reproduction & des Comportements, INRA/CNRS/Université de Tours, France
| | - David N Palmer
- Faculty of Agriculture and Life Sciences, Lincoln University, New Zealand
| | - Tracy R Melzer
- Department of Medicine, University of Otago, Christchurch, and New Zealand Brain Research Institute, New Zealand
| | - Nadia L Mitchell
- Faculty of Agriculture and Life Sciences, Lincoln University, New Zealand.,Department of Radiology, University of Otago, Christchurch, New Zealand
| | - Matthieu Keller
- Physiologie de la Reproduction & des Comportements, INRA/CNRS/Université de Tours, France
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12
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Gkogkidis CA, Bentler C, Wang X, Gierthmuehlen M, Scheiwe C, Schmitz HC, Haberstroh J, Stieglitz T, Ball T. Neurophysiological Evaluation of a Customizable μECoG-based Wireless Brain Implant. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2018; 2018:2953-2956. [PMID: 30441019 DOI: 10.1109/embc.2018.8513044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The number of implantable bidirectional neural interfaces available for neuroscientific research applications is still limited, despite the rapidly increasing number of customized components. We previously reported on how to translate available components into "ready-to-use" wireless implantable systems utilizing components off-the-shelf (COTS). The aim of the present study was to verify the viability of a micro-electrocorticographic ($\mu $ECoG) device built by this approach. Functionality for both neural recording and stimulation was evaluated in an ovine animal model using acoustic stimuli and cortical electrical stimulation, respectively. We show that auditory evoked responses were reliably recorded in both time and frequency domain and present data that demonstrates the cortical electrical stimulation functionality. The successful recording of neuronal activity suggests that the device can compete with existing implantable systems as a neurotechnological research tool.
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13
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Hoch K, Pothof F, Becker F, Paul O, Ruther P. Development, Modeling, Fabrication, and Characterization of a Magnetic, Micro-Spring-Suspended System for the Safe Electrical Interconnection of Neural Implants. MICROMACHINES 2018; 9:mi9090424. [PMID: 30424357 PMCID: PMC6187687 DOI: 10.3390/mi9090424] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 08/20/2018] [Accepted: 08/21/2018] [Indexed: 11/29/2022]
Abstract
The development of innovative tools for neuroscientific research is based on in vivo tests typically applied to small animals. Most often, the interfacing of neural probes relies on commercially available connector systems which are difficult to handle during connection, particularly when freely behaving animals are involved. Furthermore, the connectors often exert high mechanical forces during plugging and unplugging, potentially damaging the fragile bone structure. In order to facilitate connector usage and increase the safety of laboratory animals, we developed a new magnetic connector system circumventing the drawbacks of existing tools. The connector system uses multiple magnet pairs and spring-suspended electrical contact pads realized using micro-electromechanical systems (MEMS) technologies. While the contact pad suspension increases the system tolerance in view of geometrical variations, we achieved a reliable self-alignment of the connector parts at ±50 µm provided by the specifically oriented magnet pairs and without the need of alignment pins. While connection forces are negligible, we can adjust the forces during connector release by modifying the magnet distance. With the connector test structures developed here, we achieved an electrical connection yield of 100%. Based on these findings, we expect that in vivo experiments with freely behaving animals will be facilitated with improved animal safety.
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Affiliation(s)
- Katharina Hoch
- Department of Microsystems Engineering (IMTEK), University of Freiburg, 79110 Freiburg, Germany.
| | - Frederick Pothof
- Department of Microsystems Engineering (IMTEK), University of Freiburg, 79110 Freiburg, Germany.
| | - Felix Becker
- Department of Microsystems Engineering (IMTEK), University of Freiburg, 79110 Freiburg, Germany.
| | - Oliver Paul
- Department of Microsystems Engineering (IMTEK), University of Freiburg, 79110 Freiburg, Germany.
- BrainLinks-BrainTools Cluster of Excellence, University of Freiburg, 79110 Freiburg, Germany.
| | - Patrick Ruther
- Department of Microsystems Engineering (IMTEK), University of Freiburg, 79110 Freiburg, Germany.
- BrainLinks-BrainTools Cluster of Excellence, University of Freiburg, 79110 Freiburg, Germany.
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14
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Kellmeyer P, Grosse-Wentrup M, Schulze-Bonhage A, Ziemann U, Ball T. Electrophysiological correlates of neurodegeneration in motor and non-motor brain regions in amyotrophic lateral sclerosis-implications for brain-computer interfacing. J Neural Eng 2018; 15:041003. [PMID: 29676287 DOI: 10.1088/1741-2552/aabfa5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE For patients with amyotrophic lateral sclerosis (ALS) who are suffering from severe communication or motor problems, brain-computer interfaces (BCIs) can improve the quality of life and patient autonomy. However, current BCI systems are not as widely used as their potential and patient demand would let assume. This underutilization is a result of technological as well as user-based limitations but also of the comparatively poor performance of currently existing BCIs in patients with late-stage ALS, particularly in the locked-in state. APPROACH Here we review a broad range of electrophysiological studies in ALS patients with the aim to identify electrophysiological correlates of ALS-related neurodegeneration in motor and non-motor brain regions in to better understand potential neurophysiological limitations of current BCI systems for ALS patients. To this end we analyze studies in ALS patients that investigated basic sensory evoked potentials, resting-state and task-based paradigms using electroencephalography or electrocorticography for basic research purposes as well as for brain-computer interfacing. Main results and significance. Our review underscores that, similarly to mounting evidence from neuroimaging and neuropathology, electrophysiological measures too indicate neurodegeneration in non-motor areas in ALS. Furthermore, we identify an unexpected gap of basic and advanced electrophysiological studies in late-stage ALS patients, particularly in the locked-in state. We propose a research strategy on how to fill this gap in order to improve the design and performance of future BCI systems for this patient group.
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Affiliation(s)
- Philipp Kellmeyer
- Translational Neurotechnology Lab, Department of Neurosurgery, Medical Center-University of Freiburg, Freiburg im Breisgau, Germany. Cluster of Excellence BrainLinks-BrainTools, University of Freiburg, Freiburg im Breisgau, Germany
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15
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Casimo K, Levinson LH, Zanos S, Gkogkidis CA, Ball T, Fetz E, Weaver KE, Ojemann JG. An interspecies comparative study of invasive electrophysiological functional connectivity. Brain Behav 2017; 7:e00863. [PMID: 29299382 PMCID: PMC5745242 DOI: 10.1002/brb3.863] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 09/27/2017] [Indexed: 11/13/2022] Open
Abstract
INTRODUCTION Resting-state connectivity patterns have been observed in humans and other mammal species, and can be recorded using a variety of different technologies. Functional connectivity has been previously compared between species using resting-state fMRI, but not in electrophysiological studies. METHODS We compared connectivity with implanted electrodes in humans (electrocorticography) to macaques and sheep (microelectrocorticography), which are capable of recording neural data at high frequencies with spatial precision. We specifically examined synchrony, implicated in functional integration between regions. RESULTS We found that connectivity strength was overwhelmingly similar in humans and monkeys for pairs of two different brain regions (prefrontal, motor, premotor, parietal), but differed more often within single brain regions. The two connectivity measures, correlation and phase locking value, were similar in most comparisons. Connectivity strength agreed more often between the species at higher frequencies. Where the species differed, monkey synchrony was stronger than human in all but one case. In contrast, human and sheep connectivity within somatosensory cortex diverged in almost all frequencies, with human connectivity stronger than sheep. DISCUSSION Our findings imply greater heterogeneity within regions in humans than in monkeys, but comparable functional interactions between regions in the two species. This suggests that monkeys may be effectively used to probe resting-state connectivity in humans, and that such findings can then be validated in humans. Although the discrepancy between humans and sheep is larger, we suggest that findings from sheep in highly invasive studies may be used to provide guidance for studies in other species.
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Affiliation(s)
- Kaitlyn Casimo
- Graduate Program in Neuroscience University of Washington Seattle WA USA.,Center for Sensorimotor Neural Engineering University of Washington Seattle WA USA
| | | | - Stavros Zanos
- Center for Sensorimotor Neural Engineering University of Washington Seattle WA USA.,Department of Physiology and Biophysics University of Washington Seattle WA USA.,Washington National Primate Research Center University of Washington Seattle WA USA.,Feinstein Institute for Medical Research New York City NY USA
| | - C Alexis Gkogkidis
- Translational Neurotechnology Laboratory Department of Neurosurgery Faculty of Medicine Medical Center - University of Freiburg Freiburg Germany.,Laboratory for Biomedical Microtechnology Department of Microsystems Engineering Faculty of Engineering University of Freiburg Freiburg Germany
| | - Tonio Ball
- Translational Neurotechnology Laboratory Department of Neurosurgery Faculty of Medicine Medical Center - University of Freiburg Freiburg Germany.,Laboratory for Biomedical Microtechnology Department of Microsystems Engineering Faculty of Engineering University of Freiburg Freiburg Germany
| | - Eberhard Fetz
- Graduate Program in Neuroscience University of Washington Seattle WA USA.,Center for Sensorimotor Neural Engineering University of Washington Seattle WA USA.,Department of Physiology and Biophysics University of Washington Seattle WA USA.,Washington National Primate Research Center University of Washington Seattle WA USA
| | - Kurt E Weaver
- Graduate Program in Neuroscience University of Washington Seattle WA USA.,Department of Radiology University of Washington Seattle WA USA.,Integrated Brain Imaging Center University of Washington Seattle WA USA
| | - Jeffrey G Ojemann
- Graduate Program in Neuroscience University of Washington Seattle WA USA.,Center for Sensorimotor Neural Engineering University of Washington Seattle WA USA.,Department of Neurological Surgery University of Washington Seattle WA USA.,Department of Neurological Surgery Seattle Children's Hospital Seattle WA USA
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16
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Gkogkidis CA, Wang X, Schubert T, Gierthmühlen M, Kohler F, Schulze-Bonhage A, Burgard W, Rickert J, Haberstroh J, Schüttler M, Stieglitz T, Ball T. Closed-loop interaction with the cerebral cortex using a novel micro-ECoG-based implant: the impact of beta vs. gamma stimulation frequencies on cortico-cortical spectral responses. BRAIN-COMPUTER INTERFACES 2017. [DOI: 10.1080/2326263x.2017.1381829] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- C. Alexis Gkogkidis
- Translational Neurotechnology Lab, Department of Neurosurgery, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Laboratory for Biomedical Microtechnology, Department of Microsystems Engineering, Faculty of Engineering, University of Freiburg, Freiburg, Germany
| | - Xi Wang
- Translational Neurotechnology Lab, Department of Neurosurgery, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Laboratory for Biomedical Microtechnology, Department of Microsystems Engineering, Faculty of Engineering, University of Freiburg, Freiburg, Germany
| | - Tobias Schubert
- Department of Computer Science, Faculty of Engineering, University of Freiburg, Freiburg, Germany
| | - Mortimer Gierthmühlen
- Department of Neurosurgery, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | | | - Andreas Schulze-Bonhage
- Epilepsy Center, Department of Neurosurgery, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Wolfram Burgard
- Department of Computer Science, Faculty of Engineering, University of Freiburg, Freiburg, Germany
| | | | - Jörg Haberstroh
- CEMT, Experimental Surgery, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | | | - Thomas Stieglitz
- Laboratory for Biomedical Microtechnology, Department of Microsystems Engineering, Faculty of Engineering, University of Freiburg, Freiburg, Germany
| | - Tonio Ball
- Translational Neurotechnology Lab, Department of Neurosurgery, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg, Germany
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17
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Wang X, Gkogkidis CA, Iljina O, Fiederer LDJ, Henle C, Mader I, Kaminsky J, Stieglitz T, Gierthmuehlen M, Ball T. Mapping the fine structure of cortical activity with different micro-ECoG electrode array geometries. J Neural Eng 2017; 14:056004. [DOI: 10.1088/1741-2552/aa785e] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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18
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Kohler F, Gkogkidis CA, Bentler C, Wang X, Gierthmuehlen M, Fischer J, Stolle C, Reindl LM, Rickert J, Stieglitz T, Ball T, Schuettler M. Closed-loop interaction with the cerebral cortex: a review of wireless implant technology. BRAIN-COMPUTER INTERFACES 2017. [DOI: 10.1080/2326263x.2017.1338011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Fabian Kohler
- CorTec GmbH, Freiburg, Germany
- Laboratory for Biomedical Microtechnology, Department of Microsystems Engineering, Faculty of Engineering, University of Freiburg, Freiburg, Germany
| | - C. Alexis Gkogkidis
- Translational Neurotechnology Lab, Department of Neurosurgery, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Laboratory for Biomedical Microtechnology, Department of Microsystems Engineering, Faculty of Engineering, University of Freiburg, Freiburg, Germany
| | - Christian Bentler
- Laboratory for Biomedical Microtechnology, Department of Microsystems Engineering, Faculty of Engineering, University of Freiburg, Freiburg, Germany
| | - Xi Wang
- Translational Neurotechnology Lab, Department of Neurosurgery, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Laboratory for Biomedical Microtechnology, Department of Microsystems Engineering, Faculty of Engineering, University of Freiburg, Freiburg, Germany
| | - Mortimer Gierthmuehlen
- Translational Neurotechnology Lab, Department of Neurosurgery, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | | | | | - Leonhard M. Reindl
- Laboratory for Electrical Instrumentation, Department of Microsystems Engineering, Faculty of Engineering, University of Freiburg, Freiburg, Germany
| | | | - Thomas Stieglitz
- Laboratory for Biomedical Microtechnology, Department of Microsystems Engineering, Faculty of Engineering, University of Freiburg, Freiburg, Germany
| | - Tonio Ball
- Translational Neurotechnology Lab, Department of Neurosurgery, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
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19
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Ella A, Delgadillo JA, Chemineau P, Keller M. Computation of a high-resolution MRI 3D stereotaxic atlas of the sheep brain. J Comp Neurol 2016; 525:676-692. [PMID: 27503489 DOI: 10.1002/cne.24079] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 06/17/2016] [Accepted: 07/12/2016] [Indexed: 12/16/2022]
Abstract
The sheep model was first used in the fields of animal reproduction and veterinary sciences and then was utilized in fundamental and preclinical studies. For more than a decade, magnetic resonance (MR) studies performed on this model have been increasingly reported, especially in the field of neuroscience. To contribute to MR translational neuroscience research, a brain template and an atlas are necessary. We have recently generated the first complete T1-weighted (T1W) and T2W MR population average images (or templates) of in vivo sheep brains. In this study, we 1) defined a 3D stereotaxic coordinate system for previously established in vivo population average templates; 2) used deformation fields obtained during optimized nonlinear registrations to compute nonlinear tissues or prior probability maps (nlTPMs) of cerebrospinal fluid (CSF), gray matter (GM), and white matter (WM) tissues; 3) delineated 25 external and 28 internal sheep brain structures by segmenting both templates and nlTPMs; and 4) annotated and labeled these structures using an existing histological atlas. We built a quality high-resolution 3D atlas of average in vivo sheep brains linked to a reference stereotaxic space. The atlas and nlTPMs, associated with previously computed T1W and T2W in vivo sheep brain templates and nlTPMs, provide a complete set of imaging space that are able to be imported into other imaging software programs and could be used as standardized tools for neuroimaging studies or other neuroscience methods, such as image registration, image segmentation, identification of brain structures, implementation of recording devices, or neuronavigation. J. Comp. Neurol. 525:676-692, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Arsène Ella
- INRA, UMR 85 Physiologie de la Reproduction et des Comportements, F-37380, Nouzilly, France.,CNRS, UMR 7247, F-37380, Nouzilly, France.,Université François Rabelais, F-37041, Nouzilly, France
| | - José A Delgadillo
- Centro de Investigacion en Reproducion Caprina, Universidad Autonoma Agraria Antonio Narro, Torreon, Mexico
| | - Philippe Chemineau
- INRA, UMR 85 Physiologie de la Reproduction et des Comportements, F-37380, Nouzilly, France.,CNRS, UMR 7247, F-37380, Nouzilly, France.,Université François Rabelais, F-37041, Nouzilly, France
| | - Matthieu Keller
- INRA, UMR 85 Physiologie de la Reproduction et des Comportements, F-37380, Nouzilly, France.,CNRS, UMR 7247, F-37380, Nouzilly, France.,Université François Rabelais, F-37041, Nouzilly, France
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20
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Liyanage KA, Steward C, Moffat BA, Opie NL, Rind GS, John SE, Ronayne S, May CN, O’Brien TJ, Milne ME, Oxley TJ. Development and Implementation of a Corriedale Ovine Brain Atlas for Use in Atlas-Based Segmentation. PLoS One 2016; 11:e0155974. [PMID: 27285947 PMCID: PMC4902240 DOI: 10.1371/journal.pone.0155974] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 05/06/2016] [Indexed: 02/06/2023] Open
Abstract
Segmentation is the process of partitioning an image into subdivisions and can be applied to medical images to isolate anatomical or pathological areas for further analysis. This process can be done manually or automated by the use of image processing computer packages. Atlas-based segmentation automates this process by the use of a pre-labelled template and a registration algorithm. We developed an ovine brain atlas that can be used as a model for neurological conditions such as Parkinson's disease and focal epilepsy. 17 female Corriedale ovine brains were imaged in-vivo in a 1.5T (low-resolution) MRI scanner. 13 of the low-resolution images were combined using a template construction algorithm to form a low-resolution template. The template was labelled to form an atlas and tested by comparing manual with atlas-based segmentations against the remaining four low-resolution images. The comparisons were in the form of similarity metrics used in previous segmentation research. Dice Similarity Coefficients were utilised to determine the degree of overlap between eight independent, manual and atlas-based segmentations, with values ranging from 0 (no overlap) to 1 (complete overlap). For 7 of these 8 segmented areas, we achieved a Dice Similarity Coefficient of 0.5-0.8. The amygdala was difficult to segment due to its variable location and similar intensity to surrounding tissues resulting in Dice Coefficients of 0.0-0.2. We developed a low resolution ovine brain atlas with eight clinically relevant areas labelled. This brain atlas performed comparably to prior human atlases described in the literature and to intra-observer error providing an atlas that can be used to guide further research using ovine brains as a model and is hosted online for public access.
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Affiliation(s)
- Kishan Andre Liyanage
- Vascular Bionics Laboratory, Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Parkville, Victoria, Australia
- Department of Radiology, Royal Melbourne Hospital, University of Melbourne, Parkville, Victoria, Australia
| | - Christopher Steward
- Department of Radiology, Royal Melbourne Hospital, University of Melbourne, Parkville, Victoria, Australia
| | - Bradford Armstrong Moffat
- Department of Radiology, Royal Melbourne Hospital, University of Melbourne, Parkville, Victoria, Australia
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Victoria, Australia
| | - Nicholas Lachlan Opie
- Vascular Bionics Laboratory, Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Parkville, Victoria, Australia
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - Gil Simon Rind
- Vascular Bionics Laboratory, Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Parkville, Victoria, Australia
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - Sam Emmanuel John
- Vascular Bionics Laboratory, Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Parkville, Victoria, Australia
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
- NeuroEngineering Laboratory, Department of Electrical & Electronic Engineering, The University of Melbourne and Centre for Neural Engineering, Parkville, Victoria, Australia
| | - Stephen Ronayne
- Vascular Bionics Laboratory, Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Parkville, Victoria, Australia
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - Clive Newton May
- Vascular Bionics Laboratory, Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Parkville, Victoria, Australia
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - Terence John O’Brien
- Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Parkville, Victoria, Australia
| | - Marjorie Eileen Milne
- Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Werribee, Victoria, Australia
| | - Thomas James Oxley
- Vascular Bionics Laboratory, Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Parkville, Victoria, Australia
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
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21
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Barriga-Rivera A, Eiber CD, Dodds CWD, Fung AT, Tatarinoff V, Lovell NH, Suaning GJ. Electrically evoked potentials in an ovine model for the evaluation of visual prosthesis efficacy. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2016; 2015:3359-62. [PMID: 26737012 DOI: 10.1109/embc.2015.7319112] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Visual prostheses are becoming a reality as a therapy to restore functional vision to the blind. New stimulation strategies and novel electrode designs are contributing to accelerate the development of such devices triggering the interest of scientists, clinicians and the blind community worldwide. In this scenario, there is a need for large animal models that are suitable for preclinical testing of retinal neuroprostheses. This study presents an electrophysiology assessment of an ovine model for single and simultaneous electrode stimulation from the suprachoroidal space, using symmetric biphasic current pulses with a monopolar return configuration. Visually and electrically evoked potentials were recorded using supradural surface electrodes, showing charge thresholds comparable to those in humans. This model represents an alternative to feline or canine models with analogous activation levels and an eye anatomy similar to that of humans.
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22
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Kohler F, Michiels R, Schuettler M, Stieglitz T. Development of a bending test procedure for the characterization of flexible ECoG electrode arrays. CURRENT DIRECTIONS IN BIOMEDICAL ENGINEERING 2015. [DOI: 10.1515/cdbme-2015-0122] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abstract
An automatized mechanical test has been developed to characterize flexible ECoG and grid electrode arrays under cyclic bending load. Electrodes with different test structures were designed and the bending cycle dependant failure rate was found to follow a Weibull distribution. A corresponding failure mode analysis revealed a characteristic lifetime of more than 25000 bending cycles for some designs. However, design parameters as e.g. a smaller track width reduced this lifetime by a factor of two. In comparison to a similar BMI grid electrode array which was implanted for several months in an animal, failure patterns were comparable to those simulated with the bending test.
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Affiliation(s)
- Fabian Kohler
- University of Freiburg, Dept. of Microsystems Engineering IMTEK, Laboratory for Biomedical Microtechnology, Freiburg, Germany, BrainLinks-BrainTools DFG Cluster of Excellence (ExC1086) and Cortec GmbH Freiburg
| | - Rebecca Michiels
- University of Freiburg, Dept. of Microsystems Engineering IMTEK, Laboratory for Bio- and Nano-Photonics
| | - Martin Schuettler
- University of Freiburg, Dept. of Microsystems Engineering IMTEK, Laboratory for Biomedical Microtechnology, Freiburg, Germany, BrainLinks-BrainTools DFG Cluster of Excellence (ExC1086) and Cortec GmbH Freiburg
| | - Thomas Stieglitz
- University of Freiburg, Dept. of Microsystems Engineering IMTEK, Laboratory for Biomedical Microtechnology, Freiburg, Germany, BrainLinks-BrainTools DFG Cluster of Excellence (ExC1086) and Cortec GmbH Freiburg
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23
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Nitzsche B, Frey S, Collins LD, Seeger J, Lobsien D, Dreyer A, Kirsten H, Stoffel MH, Fonov VS, Boltze J. A stereotaxic, population-averaged T1w ovine brain atlas including cerebral morphology and tissue volumes. Front Neuroanat 2015; 9:69. [PMID: 26089780 PMCID: PMC4455244 DOI: 10.3389/fnana.2015.00069] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Accepted: 05/12/2015] [Indexed: 01/18/2023] Open
Abstract
Standard stereotaxic reference systems play a key role in human brain studies. Stereotaxic coordinate systems have also been developed for experimental animals including non-human primates, dogs, and rodents. However, they are lacking for other species being relevant in experimental neuroscience including sheep. Here, we present a spatial, unbiased ovine brain template with tissue probability maps (TPM) that offer a detailed stereotaxic reference frame for anatomical features and localization of brain areas, thereby enabling inter-individual and cross-study comparability. Three-dimensional data sets from healthy adult Merino sheep (Ovis orientalis aries, 12 ewes and 26 neutered rams) were acquired on a 1.5 T Philips MRI using a T1w sequence. Data were averaged by linear and non-linear registration algorithms. Moreover, animals were subjected to detailed brain volume analysis including examinations with respect to body weight (BW), age, and sex. The created T1w brain template provides an appropriate population-averaged ovine brain anatomy in a spatial standard coordinate system. Additionally, TPM for gray (GM) and white (WM) matter as well as cerebrospinal fluid (CSF) classification enabled automatic prior-based tissue segmentation using statistical parametric mapping (SPM). Overall, a positive correlation of GM volume and BW explained about 15% of the variance of GM while a positive correlation between WM and age was found. Absolute tissue volume differences were not detected, indeed ewes showed significantly more GM per bodyweight as compared to neutered rams. The created framework including spatial brain template and TPM represent a useful tool for unbiased automatic image preprocessing and morphological characterization in sheep. Therefore, the reported results may serve as a starting point for further experimental and/or translational research aiming at in vivo analysis in this species.
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Affiliation(s)
- Björn Nitzsche
- Department of Cell Therapy, Fraunhofer Institute for Cell Therapy and Immunology Leipzig, Germany ; Faculty of Veterinary Medicine, Institute of Anatomy, Histology and Embryology, University of Leipzig Leipzig, Germany
| | - Stephen Frey
- McConnell Brain Imaging Centre, Montreal Neurological Institute and Hospital, McGill University Montreal, QC, Canada
| | - Louis D Collins
- McConnell Brain Imaging Centre, Montreal Neurological Institute and Hospital, McGill University Montreal, QC, Canada
| | - Johannes Seeger
- Faculty of Veterinary Medicine, Institute of Anatomy, Histology and Embryology, University of Leipzig Leipzig, Germany
| | - Donald Lobsien
- Department of Neuroradiology, University Hospital of Leipzig Leipzig, Germany
| | - Antje Dreyer
- Department of Cell Therapy, Fraunhofer Institute for Cell Therapy and Immunology Leipzig, Germany ; Translational Centre for Regenerative Medicine, University of Leipzig Leipzig, Germany
| | - Holger Kirsten
- Department of Cell Therapy, Fraunhofer Institute for Cell Therapy and Immunology Leipzig, Germany ; Faculty of Medicine, Institute for Medical Informatics, Statistics and Epidemiology, University of Leipzig Leipzig, Germany ; LIFE Center (Leipzig Interdisciplinary Research Cluster of Genetic Factors, Phenotypes and Environment), University of Leipzig Leipzig, Germany
| | - Michael H Stoffel
- Division of Veterinary Anatomy, Vetsuisse Faculty, University of Bern Bern, Switzerland
| | - Vladimir S Fonov
- McConnell Brain Imaging Centre, Montreal Neurological Institute and Hospital, McGill University Montreal, QC, Canada
| | - Johannes Boltze
- Department of Cell Therapy, Fraunhofer Institute for Cell Therapy and Immunology Leipzig, Germany ; Translational Centre for Regenerative Medicine, University of Leipzig Leipzig, Germany ; Neurovascular Regulation Laboratory at Neuroscience Center, Massachusetts General Hospital and Harvard Medical School Charlestown, MA, USA
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