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Kamelian Rad M, Ahmadi-Pajouh MA, Saviz M. Selective electrical stimulation of low versus high diameter myelinated fibers and its application in pain relief: a modeling study. J Math Biol 2022; 86:3. [PMID: 36436158 DOI: 10.1007/s00285-022-01833-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 10/29/2022] [Accepted: 11/04/2022] [Indexed: 11/29/2022]
Abstract
Electrical stimulation of peripheral nerve fibers has always been an attractive field of research. Due to the higher activation threshold, the stimulation of small fibers is accompanied by the stimulation of larger ones. It is therefore necessary to design a specific stimulation theme in order to only activate narrow fibers. There is evidence that stimulating Aδ fibers can activate endogenous pain-relieving mechanisms. However, both selective stimulation and reducing pain by activating small nociceptive fibers are still poorly investigated. In this study, using high-frequency stimulation waveforms (5-20 kHz), computational modeling provides a simple framework for activating narrow nociceptive fibers. Additionally, a model of myelinated nerve fibers is modified by including sodium-potassium pump and investigating its effects on neuronal stimulation. Besides, a modified mathematical model of pain processing circuits in the dorsal horn is presented that consists of supraspinal pain control mechanisms. Hence, by employing this pain-modulating model, the mechanism of the reduction of pain by activating nociceptive fibers is explored. In the case of two fibers with the same distance from the point source electrode, a single stimulation waveform is capable of blocking one large fiber and stimulating another small fiber. Noteworthy, the Na/K pump model demonstrated that it does not have a significant effect on the activation threshold and firing frequency of fiber. Ultimately, results suggest that the descending pathways of Locus coeruleus may effectively contribute to pain relief through stimulation of nociceptive fibers, which will be beneficial for clinical interventions.
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Affiliation(s)
- Mohsen Kamelian Rad
- Department of Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran
| | | | - Mehrdad Saviz
- Department of Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran
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Meriaux C, Hohnen R, Schipper S, Zare A, Jahanshahi A, Birder LA, Temel Y, van Koeveringe GA. Neuronal Activation in the Periaqueductal Gray Matter Upon Electrical Stimulation of the Bladder. Front Cell Neurosci 2018; 12:133. [PMID: 29867366 PMCID: PMC5968116 DOI: 10.3389/fncel.2018.00133] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 04/30/2018] [Indexed: 12/27/2022] Open
Abstract
Reflexes, that involve the spinobulbospinal pathway control both storage and voiding of urine. The periaqueductal gray matter (PAG), a pontine structure is part of the micturition pathway. Alteration in this pathway could lead to micturition disorders and urinary incontinence, such as the overactive bladder symptom complex (OABS). Although different therapeutic options exist for the management of OABS, these are either not effective in all patients. Part of the pathology of OABS is faulty sensory signaling about the filling status of the urinary bladder, which results in aberrant efferent signaling leading to overt detrusor contractions and the sensation of urgency and frequent voiding. In order to identify novel targets for therapy (i.e., structures in the central nervous system) and explore novel treatment modalities such as neuromodulation, we aimed at investigating which areas in the central nervous system are functionally activated upon sensory afferent stimulation of the bladder. Hence, we designed a robust protocol with multiple readout parameters including immunohistological and behavioral parameters during electrical stimulation of the rat urinary bladder. Bladder stimulation induced by electrical stimulation, below the voiding threshold, influences neural activity in: (1) the caudal ventrolateral PAG, close to the aqueduct; (2) the pontine micturition center and locus coeruleus; and (3) the superficial layers of the dorsal horn, sacral parasympathetic nucleus and central canal region of the spinal cord. In stimulated animals, a higher voiding frequency was observed but was not accompanied by increase in anxiety level and locomotor deficits. Taken together, this work establishes a critical role for the vlPAG in the processing of sensory information from the urinary bladder and urges future studies to investigate the potential of neuromodulatory approaches for urological diseases.
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Affiliation(s)
- Céline Meriaux
- School for Mental Health and Neuroscience (MHeNS), Maastricht University, Maastricht, Netherlands,European Graduate School of Neuroscience (EURON), Maastricht, Netherlands,*Correspondence: Céline Meriaux
| | - Ramona Hohnen
- School for Mental Health and Neuroscience (MHeNS), Maastricht University, Maastricht, Netherlands,European Graduate School of Neuroscience (EURON), Maastricht, Netherlands
| | - Sandra Schipper
- School for Mental Health and Neuroscience (MHeNS), Maastricht University, Maastricht, Netherlands,European Graduate School of Neuroscience (EURON), Maastricht, Netherlands,Department of Urology, Maastricht University Medical Center, Maastricht, Netherlands
| | - Aryo Zare
- School for Mental Health and Neuroscience (MHeNS), Maastricht University, Maastricht, Netherlands,European Graduate School of Neuroscience (EURON), Maastricht, Netherlands
| | - Ali Jahanshahi
- School for Mental Health and Neuroscience (MHeNS), Maastricht University, Maastricht, Netherlands,European Graduate School of Neuroscience (EURON), Maastricht, Netherlands,Department of Neurosurgery, Maastricht University Medical Center, Maastricht, Netherlands
| | - Lori A. Birder
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Yasin Temel
- School for Mental Health and Neuroscience (MHeNS), Maastricht University, Maastricht, Netherlands,European Graduate School of Neuroscience (EURON), Maastricht, Netherlands,Department of Neurosurgery, Maastricht University Medical Center, Maastricht, Netherlands
| | - Gommert A. van Koeveringe
- School for Mental Health and Neuroscience (MHeNS), Maastricht University, Maastricht, Netherlands,European Graduate School of Neuroscience (EURON), Maastricht, Netherlands,Department of Urology, Maastricht University Medical Center, Maastricht, Netherlands
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Spinal Cord Stimulation for Failed Back Surgery Syndrome. CURRENT PHYSICAL MEDICINE AND REHABILITATION REPORTS 2017. [DOI: 10.1007/s40141-017-0163-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Functional brain mapping using specific sensory-circuit stimulation and a theoretical graph network analysis in mice with neuropathic allodynia. Sci Rep 2016; 6:37802. [PMID: 27898057 PMCID: PMC5127182 DOI: 10.1038/srep37802] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 11/02/2016] [Indexed: 11/08/2022] Open
Abstract
Allodynia, a form of neuropathic pain, is defined as pain in response to a non-nociceptive stimulus. The brain regions responsible for pain, which are not normally activated, can be activated in allodynic mice by providing a suitable stimulus to Aβ-fibers, which transmit signals from tactile sensory fibers. Functional MRI (fMRI) can be used to objectively observe abnormal brain activation. In the present study, fMRI was conducted to investigate allodynia in mice; allodynia was generated by surgical injury at the L4 spinal nerve root, thus selectively stimulating sensory nerve fibers. In intact mice, only the primary somatosensory cortex (S1) was activated by stimulation of Aβ-fibers. Meanwhile, allodynic mice showed significantly higher BOLD signals in the anterior cingulate area (ACA) and thalamus. Using resting state fMRI, both degree and eigenvector centrality were significantly decreased in the contralateral S1, clustering coefficient and local efficiency were significantly increased in the ACA, and betweenness centrality was significantly higher in the ventral posterolateral nucleus of the thalamus. These results suggest that the observed abnormal BOLD activation is associated with defects in Aβ-fibers when Aβ-fibers in allodynic mice are selectively stimulated. The objective approach enabled by fMRI can improve our understanding of pathophysiological mechanisms and therapeutic efficacy.
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Deer TR, Mekhail N, Provenzano D, Pope J, Krames E, Leong M, Levy RM, Abejon D, Buchser E, Burton A, Buvanendran A, Candido K, Caraway D, Cousins M, DeJongste M, Diwan S, Eldabe S, Gatzinsky K, Foreman RD, Hayek S, Kim P, Kinfe T, Kloth D, Kumar K, Rizvi S, Lad SP, Liem L, Linderoth B, Mackey S, McDowell G, McRoberts P, Poree L, Prager J, Raso L, Rauck R, Russo M, Simpson B, Slavin K, Staats P, Stanton-Hicks M, Verrills P, Wellington J, Williams K, North R. The appropriate use of neurostimulation of the spinal cord and peripheral nervous system for the treatment of chronic pain and ischemic diseases: the Neuromodulation Appropriateness Consensus Committee. Neuromodulation 2015; 17:515-50; discussion 550. [PMID: 25112889 DOI: 10.1111/ner.12208] [Citation(s) in RCA: 319] [Impact Index Per Article: 35.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 01/07/2014] [Accepted: 02/28/2014] [Indexed: 02/02/2023]
Abstract
INTRODUCTION The Neuromodulation Appropriateness Consensus Committee (NACC) of the International Neuromodulation Society (INS) evaluated evidence regarding the safety and efficacy of neurostimulation to treat chronic pain, chronic critical limb ischemia, and refractory angina and recommended appropriate clinical applications. METHODS The NACC used literature reviews, expert opinion, clinical experience, and individual research. Authors consulted the Practice Parameters for the Use of Spinal Cord Stimulation in the Treatment of Neuropathic Pain (2006), systematic reviews (1984 to 2013), and prospective and randomized controlled trials (2005 to 2013) identified through PubMed, EMBASE, and Google Scholar. RESULTS Neurostimulation is relatively safe because of its minimally invasive and reversible characteristics. Comparison with medical management is difficult, as patients considered for neurostimulation have failed conservative management. Unlike alternative therapies, neurostimulation is not associated with medication-related side effects and has enduring effect. Device-related complications are not uncommon; however, the incidence is becoming less frequent as technology progresses and surgical skills improve. Randomized controlled studies support the efficacy of spinal cord stimulation in treating failed back surgery syndrome and complex regional pain syndrome. Similar studies of neurostimulation for peripheral neuropathic pain, postamputation pain, postherpetic neuralgia, and other causes of nerve injury are needed. International guidelines recommend spinal cord stimulation to treat refractory angina; other indications, such as congestive heart failure, are being investigated. CONCLUSIONS Appropriate neurostimulation is safe and effective in some chronic pain conditions. Technological refinements and clinical evidence will continue to expand its use. The NACC seeks to facilitate the efficacy and safety of neurostimulation.
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Paredes LP, Dosen S, Rattay F, Graimann B, Farina D. The impact of the stimulation frequency on closed-loop control with electrotactile feedback. J Neuroeng Rehabil 2015; 12:35. [PMID: 25889752 PMCID: PMC4403675 DOI: 10.1186/s12984-015-0022-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 02/24/2015] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Electrocutaneous stimulation can restore the missing sensory information to prosthetic users. In electrotactile feedback, the information about the prosthesis state is transmitted in the form of pulse trains. The stimulation frequency is an important parameter since it influences the data transmission rate over the feedback channel as well as the form of the elicited tactile sensations. METHODS We evaluated the influence of the stimulation frequency on the subject's ability to utilize the feedback information during electrotactile closed-loop control. Ten healthy subjects performed a real-time compensatory tracking (standard test bench) of sinusoids and pseudorandom signals using either visual feedback (benchmark) or electrocutaneous feedback in seven conditions characterized by different combinations of the stimulation frequency (FSTIM) and tracking error sampling rate (FTE). The tracking error was transmitted using two concentric electrodes placed on the forearm. The quality of tracking was assessed using the Squared Pearson Correlation Coefficient (SPCC), the Normalized Root Mean Square Tracking Error (NRMSTE) and the time delay between the reference and generated trajectories (TDIO). RESULTS The results demonstrated that FSTIM was more important for the control performance than FTE. The quality of tracking deteriorated with a decrease in the stimulation frequency, SPCC and NRMSTE (mean) were 87.5% and 9.4% in the condition 100/100 (FTE/FSTIM), respectively, and deteriorated to 61.1% and 15.3% in 5/5, respectively, while the TDIO increased from 359.8 ms in 100/100 to 1009 ms in 5/5. However, the performance recovered when the tracking error sampled at a low rate was delivered using a high stimulation frequency (SPCC = 83.6%, NRMSTE = 10.3%, TDIO = 415.6 ms, in 5/100). CONCLUSIONS The likely reason for the performance decrease and recovery was that the stimulation frequency critically influenced the tactile perception quality and thereby the effective rate of information transfer through the feedback channel. The outcome of this study can facilitate the selection of optimal system parameters for somatosensory feedback in upper limb prostheses. The results imply that the feedback variables (e.g., grasping force) should be transmitted at relatively high frequencies of stimulation (>25 Hz), but that they can be sampled at much lower rates (e.g., 5 Hz).
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Affiliation(s)
- Liliana P Paredes
- Laboratorio di Cinematica e Robotica, Fondazione Ospedale San Camillo - I.R.C.C.S., Lido di Venezia, Italy.
| | - Strahinja Dosen
- Department of Neurorehabilitation Engineering, University Medical Center Goettingen, Goettingen, Germany.
| | - Frank Rattay
- Institute for Analysis and Scientific Computing, Vienna University of Technology, Vienna, Austria.
| | - Bernhard Graimann
- Translational Research and Knowledge Management, Otto Bock Healthcare GmbH, Duderstadt, Germany.
| | - Dario Farina
- Department of Neurorehabilitation Engineering, University Medical Center Goettingen, Goettingen, Germany.
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Bicer F, Kim JY, Horowitz A, Daneshgari F, Liu G. Assessment of bladder sensation in mice with a novel device. Urology 2014; 84:490.e1-6. [PMID: 24958485 DOI: 10.1016/j.urology.2014.04.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Revised: 04/02/2014] [Accepted: 04/15/2014] [Indexed: 11/16/2022]
Abstract
OBJECTIVE To develop and test the efficacy of an implantable bladder electrode device that can be used with the Neurometer electrodiagnostic stimulator to assess fiber-specific afferent bladder sensation in the mouse. METHODS We constructed a ball-tipped platinum electrode and surgically implanted it into the mouse bladder. The Neurometer was connected to the electrode to apply selective nerve fiber stimuli (250 Hz for Aδ fibers and 5 Hz for C fibers) of increasing intensities to the bladder mucosa in the mouse to determine bladder sensory threshold (BST) values. Using 58 female C57BL/6J mice, we measured the temporal and interobserver consistency of BST measurements, the effects of intravesical administration of lidocaine and resiniferatoxin on the BST, and the effects of our device on voiding behavior and bladder mucosal integrity. RESULTS BST values at 250 and 5 Hz did not vary significantly when measured 2, 4, and 6 days after device implantation, or when obtained by 2 blinded independent observers. Intravesical lidocaine yielded a transient increase in BST values at both 250 Hz and 5 Hz, whereas resiniferatoxin yielded a significant increase only at the 5 Hz stimulus frequency after 24 hours. Moderately increased micturition frequency and decreased volume per void were observed 4 and 6 days after device implantation. Histology revealed mild inflammatory changes in the area of the bladder adjacent to the implanted BST device. CONCLUSION Assessment of neuroselective bladder sensation in mice is feasible with our device, which provides reproducible BST values for autonomic bladder afferent nerve fibers.
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Affiliation(s)
- Fuat Bicer
- Urology Institute, University Hospitals Case Medical Center, Cleveland, OH; Department of Urology, Case Western Reserve University School of Medicine, Cleveland, OH
| | - Jin Young Kim
- Urology Institute, University Hospitals Case Medical Center, Cleveland, OH; Department of Urology, Case Western Reserve University School of Medicine, Cleveland, OH
| | - Andrew Horowitz
- Urology Institute, University Hospitals Case Medical Center, Cleveland, OH; Department of Urology, Case Western Reserve University School of Medicine, Cleveland, OH
| | - Firouz Daneshgari
- Urology Institute, University Hospitals Case Medical Center, Cleveland, OH; Department of Urology, Case Western Reserve University School of Medicine, Cleveland, OH
| | - Guiming Liu
- Urology Institute, University Hospitals Case Medical Center, Cleveland, OH; Department of Urology, Case Western Reserve University School of Medicine, Cleveland, OH.
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Tang R, Martinez M, Goodman-Keiser M, Farber JP, Qin C, Foreman RD. Comparison of burst and tonic spinal cord stimulation on spinal neural processing in an animal model. Neuromodulation 2013; 17:143-51. [PMID: 24655042 DOI: 10.1111/ner.12117] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Revised: 07/13/2013] [Accepted: 08/06/2013] [Indexed: 11/28/2022]
Abstract
OBJECTIVES Spinal cord stimulation (SCS) using bursts of pulses suppressed neuropathic pain as well or better than tonic stimulation and limited the incidences of parasthesias. The present translational study explored possible differences in mechanisms of burst and tonic SCS on nociceptive spinal networks and/or the gracile nucleus supraspinal relay. MATERIALS AND METHODS Visceromotor reflexes (VMRs, a nociceptive response) or extracellular activity of either L6-S2 spinal neurons or gracile nucleus neurons were recorded during noxious somatic stimulation (pinching) and visceral stimulation (colorectal distension [CRD]) in anesthetized rats. A stimulating (unipolar, ball) electrode at L2-L3 delivered 40 Hz burst or tonic SCS at different intensities relative to motor threshold (MT). RESULTS Average MTs for burst SCS were significantly lower than for tonic SCS. Burst SCS reduced the VMR more than tonic SCS. After high-intensity SCS (90% MT), spinal neuronal responses to CRD and pinch were reduced similarly for burst and tonic SCS. At low-intensity SCS (60% MT), only burst SCS significantly decreased the nociceptive somatic response. Tonic but not burst SCS significantly increased spontaneous activity of neurons in the gracile nucleus. CONCLUSION Based on the clinically relevant burst versus tonic parameters used in this study, burst SCS is more efficacious than tonic SCS in attenuating visceral nociception. Burst and tonic SCS also suppress lumbosacral neuronal responses to noxious somatic and visceral stimuli; however, burst SCS has a greater inhibitory effect on the neuronal response to noxious somatic stimuli than to noxious visceral stimuli. Reduced or abolished paresthesia in patients may be due in part to burst SCS not increasing spontaneous activity of neurons in the gracile nucleus.
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Affiliation(s)
- Rurong Tang
- Department of Physiology, University of Oklahoma Health Science Center, Oklahoma City, OK, USA; Department of Anesthesiology, The First Hospital of China Medical University, Shenyang, China
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Freeman DK, Rizzo JF, Fried SI. Encoding visual information in retinal ganglion cells with prosthetic stimulation. J Neural Eng 2011; 8:035005. [PMID: 21593546 PMCID: PMC3157751 DOI: 10.1088/1741-2560/8/3/035005] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Retinal prostheses aim to restore functional vision to those blinded by outer retinal diseases using electric stimulation of surviving retinal neurons. The ability to replicate the spatiotemporal pattern of ganglion cell spike trains present under normal viewing conditions is presumably an important factor for restoring high-quality vision. In order to replicate such activity with a retinal prosthesis, it is important to consider both how visual information is encoded in ganglion cell spike trains, and how retinal neurons respond to electric stimulation. The goal of the current review is to bring together these two concepts in order to guide the development of more effective stimulation strategies. We review the experiments to date that have studied how retinal neurons respond to electric stimulation and discuss these findings in the context of known retinal signaling strategies. The results from such in vitro studies reveal the advantages and disadvantages of activating the ganglion cell directly with the electric stimulus (direct activation) as compared to activation of neurons that are presynaptic to the ganglion cell (indirect activation). While direct activation allows high temporal but low spatial resolution, indirect activation yields improved spatial resolution but poor temporal resolution. Finally, we use knowledge gained from in vitro experiments to infer the patterns of elicited activity in ongoing human trials, providing insights into some of the factors limiting the quality of prosthetic vision.
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Affiliation(s)
- Daniel K Freeman
- Center for Innovative Visual Rehabilitation, Boston VA Healthcare System, 150 South Huntington Ave, Boston, MA 02130, USA.
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Jeng J, Tang S, Molnar A, Desai NJ, Fried SI. The sodium channel band shapes the response to electric stimulation in retinal ganglion cells. J Neural Eng 2011; 8:036022. [PMID: 21558602 PMCID: PMC3154029 DOI: 10.1088/1741-2560/8/3/036022] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
To improve the quality of prosthetic vision, it is desirable to understand how targeted retinal neurons respond to stimulation. Unfortunately, the factors that shape the response of a single neuron to stimulation are not well understood. A dense band of voltage-gated sodium channels within the proximal axon of retinal ganglion cells is the site most sensitive to electric stimulation, suggesting that band properties are likely to influence the response to stimulation. Here, we examined how three band properties influence sensitivity using a morphologically realistic ganglion cell model in NEURON. Longer bands were more sensitive to short-duration pulses than shorter bands and increasing the distance between band and soma also increased sensitivity. Simulations using the known limits of band length and location resulted in a sensitivity difference of approximately 2. Additional simulations tested how changes to sodium channel conductance within the band influenced threshold and found that the sensitivity difference increased to a factor of nearly 3. This is close to the factor of 5 difference measured in physiological studies suggesting that band properties contribute significantly to the sensitivity differences found between different types of retinal neurons.
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Affiliation(s)
- J Jeng
- Center for Innovative Visual Rehabilitation, Boston VA Healthcare System, 150 South Huntington Ave, Boston, MA 02130, USA
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On the selective activation of unmyelinated C-fibers using sinusoidal electrical stimulation: an ERP study. Clin Neurophysiol 2011; 122:1042-7. [PMID: 21353630 DOI: 10.1016/j.clinph.2011.01.046] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2010] [Revised: 01/07/2011] [Accepted: 01/31/2011] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To verify the possibility of selective activation of C-fibers by a 5-Hz transcutaneous electrical stimulus. METHODS Because Aβ-, Aδ- and C-fibers have different conduction velocities, we verified the selective activation of A- and C-fibers on the basis of evoked potential latencies. We tested whether a 5-Hz sinusoidal electric stimulus could selectively activate C-fibers and consequently generate ultra-late N2/P2 components in the 750-1200 ms range. RESULTS We found that a 5-Hz sine wave stimulus, whether of high or low intensity, elicited N2/P2 complexes only in the late latencies (160-390 ms), suggesting that A-fibers were concomitantly activated along with C-fibers. CONCLUSIONS These findings are in agreement with those of previous simulation studies suggesting that activation of fibers of diameter less than 2.5 μm (i.e., C-fibers) at the 5-Hz frequency requires accompanying activity from Aβ- and Aδ-fibers. SIGNIFICANCE Transcutaneous electrical stimulation with sine wave currents of different frequencies does not seem to be a reliable method for the selective assessment of somatosensory pathways.
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Freeman DK, Eddington DK, Rizzo JF, Fried SI. Selective activation of neuronal targets with sinusoidal electric stimulation. J Neurophysiol 2010; 104:2778-91. [PMID: 20810683 PMCID: PMC2997038 DOI: 10.1152/jn.00551.2010] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Accepted: 08/31/2010] [Indexed: 11/22/2022] Open
Abstract
Electric stimulation of the CNS is being evaluated as a treatment modality for a variety of neurological, psychiatric, and sensory disorders. Despite considerable success in some applications, existing stimulation techniques offer little control over which cell types or neuronal substructures are activated by stimulation. The ability to more precisely control neuronal activation would likely improve the clinical outcomes associated with these applications. Here, we show that specific frequencies of sinusoidal stimulation can be used to preferentially activate certain retinal cell types: photoreceptors are activated at 5 Hz, bipolar cells at 25 Hz, and ganglion cells at 100 Hz. In addition, low-frequency stimulation (≤25 Hz) did not activate passing axons but still elicited robust synaptically mediated responses in ganglion cells; therefore, elicited neural activity is confined to within a focal region around the stimulating electrode. Our results suggest that sinusoidal stimulation provides significantly improved control over elicited neural activity relative to conventional pulsatile stimulation.
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Affiliation(s)
- Daniel K Freeman
- Center for Innovative Visual Rehabilitation, Boston Veterans Administration Healthcare System, Boston, Massachusetts, USA
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De Ridder D, Vanneste S, Plazier M, van der Loo E, Menovsky T. Burst Spinal Cord Stimulation. Neurosurgery 2010; 66:986-90. [DOI: 10.1227/01.neu.0000368153.44883.b3] [Citation(s) in RCA: 270] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Abstract
INTRODUCTION
Spinal cord stimulation is commonly used for neuropathic pain modulation. The major side effect is the onset of paresthesia. The authors describe a new stimulation design that suppresses pain as well as, or even better than, the currently used stimulation, but without creating paresthesia.
METHODS
A spinal cord electrode (Lamitrode) for neuropathic pain was implanted in 12 patients via laminectomy: 4 at the C2 level and 7 at the T8–T9 level for cervicobrachialgia and lumboischialgia, respectively (1 at T11 at another center). During external stimulation, the patients received the classic tonic stimulation (40 or 50 Hz) and the new burst stimulation (40-Hz burst with 5 spikes at 500 Hz per burst).
RESULTS
Pain scores were measured using a visual analog scale and the McGill Short Form preoperatively and during tonic and burst stimulation. Paresthesia was scored as present or not present. Burst stimulation was significantly better for pain suppression, by both the visual analog scale score and the McGill Short Form score. Paresthesia was present in 92% of patients during tonic stimulation, and in only 17% during burst stimulation. Average follow-up was 20.5 months.
CONCLUSION
The authors present a new method of spinal cord stimulation using bursts that suppress neuropathic pain without the mandatory paresthesia. Pain suppression seems as good as or potentially better than that achieved with the currently used stimulation. Average follow-up after nearly 2 years (20.5 months) suggests that this stimulation design is stable.
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Affiliation(s)
- Dirk De Ridder
- BRAI2N, Department of Neurosurgery, University Hospital Antwerp, Edegem, Belgium
| | - Sven Vanneste
- BRAI2N, Department of Neurosurgery, University Hospital Antwerp, Edegem, Belgium
| | - Mark Plazier
- BRAI2N, Department of Neurosurgery, University Hospital Antwerp, Edegem, Belgium
| | - Elsa van der Loo
- BRAI2N, Department of Neurosurgery, University Hospital Antwerp, Edegem, Belgium
| | - Tomas Menovsky
- BRAI2N, Department of Neurosurgery, University Hospital Antwerp, Edegem, Belgium
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