116 results match your criteria Somatosensory Evoked Potentials: Clinical Applications

Non-Invasive Functional Evaluation of the Human Spinal Cord by Assessing the Peri-Spinal Neurovascular Network With Near Infrared Spectroscopy.

IEEE Trans Neural Syst Rehabil Eng 2021 10;29:2312-2321. Epub 2021 Nov 10.

Current medical care lacks an effective functional evaluation for the spinal cord. Magnetic resonance imaging and computed tomography mainly provide structural information of the spinal cord, while spinal somatosensory evoked potentials are limited by a low signal to noise ratio. We developed a non-invasive approach based on near-infrared spectroscopy in dual-wavelength (760 and 850 nm for deoxy- or oxyhemoglobin respectively) to record the neurovascular response (NVR) of the peri-spinal vascular network at the 7th cervical and 10th thoracic vertebral levels of the spinal cord, triggered by unilateral median nerve electrical stimulation (square pulse, 5-10 mA, 5 ms, 1 pulse every 4 minutes) at the wrist. Read More

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November 2021

Somatosensory evoked potentials in clinical practice: a review.

Arq Neuropsiquiatr 2021 09;79(9):824-831

Universidade Federal do Paraná, Complexo Hospital de Clínicas, Departamento de Clínica Médica, Serviço de Neurologia, Serviço de Doenças Neuromusculares e Desmielinizantes, Curitiba PR, Brazil.

The authors present a review of the current use of somatosensory evoked potentials (SSEPs) in neurological practice as a non-invasive neurophysiological technique. For this purpose we have reviewed articles published in English or Portuguese in the PubMed and LILACS databases. In this review, we address the role of SSEPs in neurological diseases that affect the central nervous system and the peripheral nervous system, especially in demyelinating diseases, for monitoring coma, trauma and the functioning of sensory pathways during surgical procedures. Read More

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September 2021

Effects of compressive lesions on intraoperative human spinal cord elasticity.

J Neurosurg Spine 2021 Aug 20;35(6):807-816. Epub 2021 Aug 20.

1Division of Neurosurgery, Department of Surgery, College of Medicine.

Objective: Although evaluating tissue elasticity has various clinical applications, spinal cord elasticity (SCE) in humans has never been well documented. In this study, the authors aimed to evaluate the impact of compression on human SCE in vivo.

Methods: The authors prospectively assessed SCE using intraoperative shear wave elastography (SWE). Read More

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Inter-stimulus phase coherence in steady-state somatosensory evoked potentials and its application in improving the performance of single-channel MI-BCI.

J Neural Eng 2021 06 21;18(4). Epub 2021 Jun 21.

Department of Biomedical Engineering, College of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin 300072, People's Republic of China.

. With the development of clinical applications of motor imagery-based brain-computer interfaces (MI-BCIs), a single-channel MI-BCI system that can be easily assembled is an attractive goal. However, due to the low quality of the spectral power features in the traditional MI-BCI paradigm, the recognition performance of current single-channel systems is far lower than that of multi-channel systems, impeding their use in clinical applications. Read More

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Pain Perception in Disorder of Consciousness: A Scoping Review on Current Knowledge, Clinical Applications, and Future Perspective.

Brain Sci 2021 May 20;11(5). Epub 2021 May 20.

Department of Clinical and Experimental Medicine, University of Messina, 98124 Messina, Italy.

Pain perception in individuals with prolonged disorders of consciousness (PDOC) is still a matter of debate. Advanced neuroimaging studies suggest some cortical activations even in patients with unresponsive wakefulness syndrome (UWS) compared to those with a minimally conscious state (MCS). Therefore, pain perception has to be considered even in individuals with UWS. Read More

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Moving beyond belief: A narrative review of potential biomarkers for transcutaneous vagus nerve stimulation.

Psychophysiology 2020 06 23;57(6):e13571. Epub 2020 Mar 23.

Health Psychology Research Group, Faculty of Psychology and Educational Sciences, University of Leuven, Leuven, Belgium.

Transcutaneous vagus nerve stimulation (tVNS) is a non-invasive neurostimulation technique that is currently being tested as a potential treatment for a myriad of neurological and psychiatric disorders. However, the working mechanisms underlying tVNS are poorly understood and it remains unclear whether stimulation activates the vagus nerve for every participant. Finding a biological marker of tVNS is imperative, as it can help guide research on clinical applications and can inform researchers on optimal stimulation sites and parameters to further optimize treatment efficacy. Read More

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Cuff and sieve electrode (CASE): The combination of neural electrodes for bi-directional peripheral nerve interfacing.

J Neurosci Methods 2020 04 22;336:108602. Epub 2020 Jan 22.

Department of Electrical and Computer Engineering, United States. Electronic address:

Background: A number of peripheral nerve interfaces for nerve stimulation and recording exist for the purpose of controlling neural prostheses, each with a set of advantages and disadvantages. The ultimate goal of neural prostheses is a seamless bi-directional communication between the peripheral nervous system and the prosthesis. Here, we developed an interfacing electrode array, the "cuff and sieve electrodes" (CASE), integrating microfabricated cuff and sieve electrodes to a single unit, to decrease the weaknesses faced by these electrode designs in isolation. Read More

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Placebo Manipulations Reverse Pain Potentiation by Unpleasant Affective Stimuli.

Front Psychiatry 2019 24;10:663. Epub 2019 Sep 24.

Department of Psychology, University of Würzburg, Würzburg, Germany.

According to the motivational priming hypothesis, unpleasant stimuli activate the motivational defense system, which in turn promotes congruent affective states such as negative emotions and pain. The question arises to what degree this bottom-up impact of emotions on pain is susceptible to a manipulation of top-down-driven expectations. To this end, we investigated whether verbal instructions implying pain potentiation vs. Read More

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September 2019

Fascicle specific targeting for selective peripheral nerve stimulation.

J Neural Eng 2019 11 11;16(6):066040. Epub 2019 Nov 11.

Nerves Incorporated, Dallas TX, United States of America.

Objective: Electrical stimulation is a blunt tool for evoking neural activity. Neurons are naturally activated asynchronously and non-uniformly, whereas stimulation drives simultaneous activity within a population of cells. These differences in activation pattern can result in unintended side effects, including muddled sensory percepts and undesirable muscle contractions. Read More

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November 2019

Direct stimulation of somatosensory cortex results in slower reaction times compared to peripheral touch in humans.

Sci Rep 2019 03 1;9(1):3292. Epub 2019 Mar 1.

Department of Neurological Surgery, University of Washington, Seattle, USA.

Direct cortical stimulation (DCS) of primary somatosensory cortex (S1) could help restore sensation and provide task-relevant feedback in a neuroprosthesis. However, the psychophysics of S1 DCS is poorly studied, including any comparison to cutaneous haptic stimulation. We compare the response times to DCS of human hand somatosensory cortex through electrocorticographic grids with response times to haptic stimuli delivered to the hand in four subjects. Read More

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A systematic review investigating the relationship of electroencephalography and magnetoencephalography measurements with sensorimotor upper limb impairments after stroke.

J Neurosci Methods 2019 01 14;311:318-330. Epub 2018 Aug 14.

Department of Rehabilitation Sciences, KU Leuven - University of Leuven, Tervuursevest 101, 3001, Leuven, Belgium.

Background: Predicting sensorimotor upper limb outcome receives continued attention in stroke. Neurophysiological measures by electroencephalography (EEG) and magnetoencephalography (MEG) could increase the accuracy of predicting sensorimotor upper limb recovery.

New Method: The aim of this systematic review was to summarize the current evidence for EEG/MEG-based measures to index neural activity after stroke and the relationship between abnormal neural activity and sensorimotor upper limb impairment. Read More

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January 2019

Electrodiagnostic applications of somatosensory evoked high-frequency EEG oscillations: Technical considerations.

Brain Res Bull 2018 03 2;137:351-355. Epub 2018 Feb 2.

Institute of Neuroscience, The Medical School, Newcastle University, NE2 4HH, UK; Department of Neurology, Royal Victoria Infirmary, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, NE1 4LP, UK; Department of Clinical Neurophysiology, Royal Victoria Infirmary, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, NE1 4LP, UK. Electronic address:

Introduction: High frequency oscillations (HFOs) embedded within the somatosensory evoked potential (SEP) are not routinely recorded/measured as part of standard clinical SEPs. However, HFOs could provide important additional diagnostic/prognostic information in various patient groups in whom SEPs are tested routinely. One area is the management of patients with hypoxic ischaemic encephalopathy (HIE) in the intensive care unit (ICU). Read More

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A pilot study to record visual evoked potentials during prone spine surgery using the SightSaver™ photic visual stimulator.

J Clin Monit Comput 2018 Oct 20;32(5):889-895. Epub 2017 Dec 20.

Department of Anesthesiology, Hospital for Special Surgery, 535 East 70th Street, New York, NY, 10021, USA.

This is a pilot study to assess the clinical safety and efficacy of recording real-time flash visual evoked potentials (VEPs) using the SightSaver Visual Stimulator mask during prone spine surgery. A prospective, observational pilot study. Twenty patients presenting for spine surgery (microdiscectomy, 1-2 level lumbar fusion, or > 2 levels thoraco-lumbar fusion) were enrolled. Read More

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October 2018

A new psychometric questionnaire for reporting of somatosensory percepts.

J Neural Eng 2018 02;15(1):013002

Department of Neuroscience and Department of Clinical Neuroscience, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta.

Objective: There have been remarkable advances over the past decade in neural prostheses to restore lost motor function. However, restoration of somatosensory feedback, which is essential for fine motor control and user acceptance, has lagged behind. With an increasing interest in using electrical stimulation to restore somatosensory sensations within the peripheral (PNS) and central nervous systems (CNS), it is critical to characterize the percepts evoked by electrical stimulation in a standardized manner with a validated psychometric questionnaire. Read More

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February 2018

Fluid biomarker and electrophysiological outcome measures for progressive MS trials.

Mult Scler 2017 Oct;23(12):1600-1613

Neurologic Clinic and Policlinic, Departments of Medicine, Biomedicine and Clinical Research, University Hospital of Basel, University of Basel, Basel, Switzerland.

Progressive multiple sclerosis (MS) is characterized by insidious clinical worsening that is difficult to accurately quantify and predict. Biofluid markers and electrophysiological measures are potential candidate outcome measures in clinical trials, allowing the quantification of nervous damage occurring in the disease. Neurofilaments are highly specific neuronal proteins. Read More

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October 2017

Analgesia induced by self-initiated electrotactile sensation is mediated by top-down modulations.

Psychophysiology 2017 06 7;54(6):848-856. Epub 2017 Feb 7.

CAS Key Laboratory of Mental Health, Institute of Psychology, Beijing, China.

It is well known that sensory perception can be attenuated when sensory stimuli are controlled by self-initiated actions. This phenomenon is explained by the consistency between forward models of anticipated action effects and actual sensory feedback. Specifically, the brain state related to the binding between motor processing and sensory perception would have inhibitory function by gating sensory information via top-down control. Read More

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Somatosensory Evoked Potentials in Patients with Hypoxic-Ischemic Brain Injury.

Semin Neurol 2017 Feb 1;37(1):60-65. Epub 2017 Feb 1.

Departments of Clinical Neurophysiology and Neurology, Medisch Spectrum Twente, Enschede, The Netherlands.

Predicting the future of patients with hypoxic-ischemic encephalopathy after successful cardiopulmonary resuscitation is often difficult. Registration of the median nerve somatosensory evoked potential (SSEP) can assist in the neurologic evaluation in these patients. In this article, the authors discuss the principles, applications, and limitations of SSEP registration in the intensive care unit, with a focus on prognostication. Read More

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February 2017

Comparison of Etanercept, Etomidate and Erythropoietin and Their Combinations in Experimentally-Induced Spinal Cord Injury.

Turk Neurosurg 2016 ;26(6):930-936

Ankara University, Faculty of Veterinary Medicine, Department of Surgery, Ankara, Turkey.

Aim: The aim of this study was to compare the preventive effects of Etanercept, Etomidate, Erythropoietin and their combination in experimentally induced spinal cord trauma by clinical, histopathological, electrophysiological parameters and biochemical examination.

Material And Methods: 85 healthy female Wistar-Albino rats were used in this study. Rats were divided 8 trauma groups that consisted of 10 rats for each, and 5 rats for the sham group. Read More

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Independent Component Decomposition of Human Somatosensory Evoked Potentials Recorded by Micro-Electrocorticography.

Int J Neural Syst 2017 Jun 18;27(4):1650052. Epub 2016 Aug 18.

1 Center for Translational Neurophysiology [email protected], Istituto Italiano di Tecnologia, Via Fossato di Mortara 17-19, 44121 Ferrara, Italy.

High-density surface microelectrodes for electrocorticography (ECoG) have become more common in recent years for recording electrical signals from the cortex. With an acceptable invasiveness/signal fidelity trade-off and high spatial resolution, micro-ECoG is a promising tool to resolve fine task-related spatial-temporal dynamics. However, volume conduction - not a negligible phenomenon - is likely to frustrate efforts to obtain reliable and resolved signals from a sub-millimeter electrode array. Read More

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Fully automated quality assurance and localization of volumetric MEG for single-subject mapping.

J Neurosci Methods 2016 06 15;266:21-31. Epub 2016 Mar 15.

Dalhousie University, Canada; IWK Health Centre, Canada.

Background: Robust and reproducible source mapping with magnetoencephalography is particularly challenging at the individual level. We evaluated a receiver-operating characteristic reliability (ROC-r) method for automated production of volumetric MEG maps in single-subjects. ROC-r provides quality assurance comparable to that offered by goodness-of-fit (GoF) and confidence volume (CV) for equivalent current dipole (ECD) modeling. Read More

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A controlled spinal cord contusion for the rhesus macaque monkey.

Exp Neurol 2016 May 11;279:261-273. Epub 2016 Feb 11.

Norton Neuroscience Institute, Norton Healthcare, Louisville, KY 40202, USA; Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, Louisville, KY 40292, USA. Electronic address:

Most in vivo spinal cord injury (SCI) experimental models use rodents. Due to the anatomical and functional differences between rodents and humans, reliable large animal models, such as non-human primates, of SCI are critically needed to facilitate translation of laboratory discoveries to clinical applications. Here we report the establishment of a controlled spinal contusion model that produces severity-dependent functional and histological deficits in non-human primates. Read More

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Clinical Applications for EPs in the ICU.

J Clin Neurophysiol 2015 Dec;32(6):472-80

*Neuroscience Institute, The Queen's Medical Center, Honolulu, Hawaii, U.S.A.; †The University of Hawaii John A. Burns School of Medicine, Honolulu, Hawaii, U.S.A.; and ‡Department of Neurology, Johns Hopkins Bayview Medical Center, Baltimore, Maryland, U.S.A.

In critically ill patients, evoked potential (EP) testing is an important tool for measuring neurologic function, signal transmission, and secondary processing of sensory information in real time. Evoked potential measures conduction along the peripheral and central sensory pathways with longer-latency potentials representing more complex thalamocortical and intracortical processing. In critically ill patients with limited neurologic exams, EP provides a window into brain function and the potential for recovery of consciousness. Read More

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December 2015

Neuromodulation accompanying focused ultrasound-induced blood-brain barrier opening.

Sci Rep 2015 Oct 22;5:15477. Epub 2015 Oct 22.

Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, 5 Fu-shin Street, Kwei-Shan, Tao-Yuan, Taiwan, 333, R.O.C.

Burst-mode focused ultrasound (FUS) induces microbubble cavitation in the vasculature and temporarily disrupts the blood-brain barrier (BBB) to enable therapeutic agent delivery. However, it remains unclear whether FUS-induced BBB opening is accompanied by neuromodulation. Here we characterized the functional effects of FUS-induced BBB opening by measuring changes in somatosensory evoked potentials (SSEPs) and blood-oxygen-level dependent (BOLD) responses. Read More

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October 2015

Early Diagnosis and Monitoring of Neurodegenerative Langerhans Cell Histiocytosis.

PLoS One 2015 15;10(7):e0131635. Epub 2015 Jul 15.

Pediatric Hematology Oncology, Meyer Children's University Hospital, Florence, Italy; Direzione Generale, Azienda Sanitaria Provinciale 7, Ragusa, Italy.

Background: Neurodegenerative Langerhans Cell Histiocytosis (ND-LCH) is a rare, unpredictable consequence that may devastate the quality of life of patients cured from LCH. We prospectively applied a multidisciplinary diagnostic work-up to early identify and follow-up patients with ND-LCH, with the ultimate goal of better determining the appropriate time for starting therapy.

Methods: We studied 27 children and young adults with either ND-LCH verified by structural magnetic resonance imaging (MRI) (group 1) or specific risk factors for (diabetes insipidus, craniofacial bone lesions), but no evidence of, neurodegenerative MRI changes (group 2). Read More

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Safety and neurological assessments after autologous transplantation of bone marrow mesenchymal stem cells in subjects with chronic spinal cord injury.

Stem Cell Res Ther 2014 Nov 17;5(6):126. Epub 2014 Nov 17.

Introduction: The administration of stem cells holds promise as a potential therapy for spinal cord injury (SCI). Mesenchymal stem cells have advantages for clinical applications, since they can be easily obtained, are suitable for autologous transplantation and have been previously shown to induce regeneration of the spinal cord in experimental settings. Here we evaluated the feasibility, safety and potential efficacy of autologous transplantation of mesenchymal stem cells in subjects with chronic complete SCI. Read More

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November 2014

PEDOT-CNT-Coated Low-Impedance, Ultra-Flexible, and Brain-Conformable Micro-ECoG Arrays.

IEEE Trans Neural Syst Rehabil Eng 2015 May 25;23(3):342-50. Epub 2014 Jul 25.

Electrocorticography (ECoG) is becoming a common tool for clinical applications, such as preparing patients for epilepsy surgery or localizing tumor boundaries, as it successfully balances invasiveness and information quality. Clinical ECoG arrays use millimeter-scale electrodes and centimeter-scale pitch and cannot precisely map neural activity. Higher-resolution electrodes are of interest for both current clinical applications, providing access to more precise neural activity localization and novel applications, such as neural prosthetics, where current information density and spatial resolution is insufficient to suitably decode signals for a chronic brain-machine interface. Read More

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Reconstruction of intracortical whisker-evoked local field potential from electrocorticogram using a model trained for spontaneous activity in the rat barrel cortex.

Neurosci Res 2014 Oct 7;87:40-8. Epub 2014 Jul 7.

Department of Developmental Physiology, National Institute for Physiological Sciences, Okazaki, Aichi 444-8686, Japan; The Graduate University for Advanced Studies, Hayama, Kanagawa 240-0193, Japan.

Electrocorticogram (ECoG) has provided neural information from the cortical surfaces, is widely used in clinical applications, and expected to be useful for brain-machine interfaces. Recent studies have defined the relationship between neural activity in deep layers of the cerebral cortex and ECoG. However, it is still unclear whether this relationship is shared across different brain states. Read More

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October 2014

Dorsal column mapping via phase reversal method: the refined technique and clinical applications.

Neurosurgery 2014 Apr;74(4):437-46; discussion 446

*Neurophysiology Division, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; ‡Department of Neurosurgery, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; §Department of Neurology, Case Western Reserve University, Cleveland, Ohio.

Background: Safe resection of intramedullary spinal cord tumors can be challenging, because they often alter the cord anatomy. Identification of neurophysiologically viable dorsal columns (DCs) and of neurophysiologically inert tissue, eg, median raphe (MR), as a safe incision site is crucial for avoiding postoperative neurological deficits. We present our experience with and improvements made to our previously described technique of DC mapping, successfully applied in a series of 12 cases. Read More

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Single-trial laser-evoked potentials feature extraction for prediction of pain perception.

Annu Int Conf IEEE Eng Med Biol Soc 2013 ;2013:4207-10

Pain is a highly subjective experience, and the availability of an objective assessment of pain perception would be of great importance for both basic and clinical applications. The objective of the present study is to develop a novel approach to extract pain-related features from single-trial laser-evoked potentials (LEPs) for classification of pain perception. The single-trial LEP feature extraction approach combines a spatial filtering using common spatial pattern (CSP) and a multiple linear regression (MLR). Read More

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Transplantation of autologous bone marrow mesenchymal stem cells in the treatment of complete and chronic cervical spinal cord injury.

Brain Res 2013 Oct 12;1533:73-9. Epub 2013 Aug 12.

Department of Neurosurgery, The Military General Hospital of PLA, Beijing 100007, China; Department of Cell Transplantation, General Hospital of The Chinese People's Armed Police Forces, Beijing 100039, China.

Neuronal injuries have been a challenging problem for treatment, especially in the case of complete and chronic cervical spinal cord injury (SCI). Recently, particular attention is paid to the potential of stem cell in treating SCI, but there are only few clinical studies and insufficient data. This study explored the efficacy of autologous bone marrow mesenchymal stem cells (BMMSCs) transplantation in the treatment of SCI. Read More

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October 2013