The Experts below are selected from a list of 123 Experts worldwide ranked by ideXlab platform
Kazunari Yoshida - One of the best experts on this subject based on the ideXlab platform.
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Comparison of effectiveness between cork-screw and peg-screw Electrodes for transcranial motor evoked potential monitoring using the finite element method.
Surgical neurology international, 2016Co-Authors: Ryosuke Tomio, Takenori Akiyama, Takayuki Ohira, Kazunari YoshidaAbstract:Intraoperative monitoring of motor evoked potentials by transcranial electric stimulation is popular in neurosurgery for monitoring motor function preservation. Some authors have reported that the peg-screw Electrodes screwed into the skull can more effectively conduct current to the brain compared to subdermal cork-screw Electrodes screwed into the skin. The aim of this study was to investigate the influence of Electrode design on transcranial motor evoked potential monitoring. We estimated differences in effectiveness between the cork-screw Electrode, peg-screw Electrode, and Cortical Electrode to produce electric fields in the brain. We used the finite element method to visualize electric fields in the brain generated by transcranial electric stimulation using realistic three-dimensional head models developed from T1-weighted images. Surfaces from five layers of the head were separated as accurately as possible. We created the "cork-screws model," "1 peg-screw model," "peg-screws model," and "Cortical Electrode model". Electric fields in the brain radially diffused from the brain surface at a maximum just below the Electrodes in coronal sections. The coronal sections and surface views of the brain showed higher electric field distributions under the peg-screw compared to the cork-screw. An extremely high electric field was observed under Cortical Electrodes. Our main finding was that the intensity of electric fields in the brain are higher in the peg-screw model than the cork-screw model.
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Comparison of effectiveness between cork-screw and peg-screw Electrodes for transcranial motor evoked potential monitoring using the finite element method
Surgical Neurology International, 2016Co-Authors: Ryosuke Tomio, Takenori Akiyama, Takayuki Ohira, Kazunari YoshidaAbstract:BACKGROUND Intraoperative monitoring of motor evoked potentials by transcranial electric stimulation is popular in neurosurgery for monitoring motor function preservation. Some authors have reported that the peg-screw Electrodes screwed into the skull can more effectively conduct current to the brain compared to subdermal cork-screw Electrodes screwed into the skin. The aim of this study was to investigate the influence of Electrode design on transcranial motor evoked potential monitoring. We estimated differences in effectiveness between the cork-screw Electrode, peg-screw Electrode, and Cortical Electrode to produce electric fields in the brain. METHODS We used the finite element method to visualize electric fields in the brain generated by transcranial electric stimulation using realistic three-dimensional head models developed from T1-weighted images. Surfaces from five layers of the head were separated as accurately as possible. We created the "cork-screws model," "1 peg-screw model," "peg-screws model," and "Cortical Electrode model". RESULTS Electric fields in the brain radially diffused from the brain surface at a maximum just below the Electrodes in coronal sections. The coronal sections and surface views of the brain showed higher electric field distributions under the peg-screw compared to the cork-screw. An extremely high electric field was observed under Cortical Electrodes. CONCLUSION Our main finding was that the intensity of electric fields in the brain are higher in the peg-screw model than the cork-screw model.
Stefan Sunaert - One of the best experts on this subject based on the ideXlab platform.
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Localization of the motor cortex on magnetic resonance images by transcranial magnetic stimulation
2015Co-Authors: K De Leener, Stefan Sunaert, Laura Seynaeve, Tom Haeck, Pieter Slagmolen, Steven De Vleeschouwer, Frederik Maes, Tom Theys, Johan Van Loon, Sylvia KovacsAbstract: 30% of people with epilepsy do not respond to medication Surgically removing the epileptogenic zone is an option... ... provided this area is not responsible for critical functions Evolution to multimodal, non-invasive patient-specific mapping of critical brain regions (MRI, fMRI, MEG, TMS) “Gold” standard for motor cortex mapping is invasive implantation of Cortical Electrode grid (electrocorticography ECoG) Navigated transcranial magnetic stimulation (TMS) offers a non-invasive alternative for Cortical mapping Aim: improve TMS based localization of the motor cortex by including patient-specific electrical field simulations based on the SimNIBS pipeline1
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Dorsolateral prefrontal cortex transcranial magnetic stimulation and Electrode implant for intractable tinnitus.
World neurosurgery, 2011Co-Authors: Dirk De Ridder, Sven Vanneste, Mark Plazier, Tomas Menovsky, Paul Van De Heyning, Silvia Kovacs, Stefan SunaertAbstract:Tinnitus is a distressing symptom that affects up to 15% of the population; no satisfactory treatment exists. We present a novel surgical approach for the treatment of intractable tinnitus based on electrical extradural stimulation of the dorsolateral prefrontal cortex via an Electrode implant. Tinnitus can be considered an auditory phantom phenomenon similar to deafferentation pain in the somatosensory system. It is characterized by gamma-band activity in the frontal cortex that can be visualized with the use of electroencephalography, magnetoencephalography, and functional magnetic resonance imaging (fMRI). Transcranial magnetic stimulation (TMS) is a noninvasive technique capable of modulating the ongoing activity of the human brain. When linked with a neuronavigation system, fMRI-guided frontal cortex TMS can be performed in a placebo-controlled way. If it is successful in suppressing tinnitus, this focal and temporary effect can be maintained in perpetuity by implanting a Cortical Electrode. A neuronavigation-based auditory fMRI-guided frontal cortex TMS session was performed in a patient experiencing intractable tinnitus, yielding 50% tinnitus suppression. Two extradural Electrodes were subsequently implanted, also based on auditory fMRI-guided navigation. Postoperatively the tinnitus has improved by 66.67% and progressively continues to improve for more than one year. Focal extradural electrical stimulation of the dorsolateral prefrontal cortex at the area of Cortical plasticity is capable of suppressing contralateral tinnitus partially. TMS might be a possible method for noninvasive studies of surgical candidates for implantation of stimulating Electrodes for tinnitus suppression. Copyright © 2012 Elsevier Inc. All rights reserved.
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Dorsolateral prefrontal cortex transcranial magnetic stimulation and Electrode implant for intractable tinnitus.
World Neurosurgery, 2011Co-Authors: Dirk De Ridder, Sven Vanneste, Mark Plazier, Tomas Menovsky, Paul Van De Heyning, Silvia Kovacs, Stefan SunaertAbstract:Objective Tinnitus is a distressing symptom that affects up to 15% of the population; no satisfactory treatment exists. We present a novel surgical approach for the treatment of intractable tinnitus based on electrical extradural stimulation of the dorsolateral prefrontal cortex via an Electrode implant. Tinnitus can be considered an auditory phantom phenomenon similar to deafferentation pain in the somatosensory system. It is characterized by gamma-band activity in the frontal cortex that can be visualized with the use of electroencephalography, magnetoencephalography, and functional magnetic resonance imaging (fMRI). Case Description Transcranial magnetic stimulation (TMS) is a noninvasive technique capable of modulating the ongoing activity of the human brain. When linked with a neuronavigation system, fMRI-guided frontal cortex TMS can be performed in a placebo-controlled way. If it is successful in suppressing tinnitus, this focal and temporary effect can be maintained in perpetuity by implanting a Cortical Electrode. A neuronavigation-based auditory fMRI-guided frontal cortex TMS session was performed in a patient experiencing intractable tinnitus, yielding 50% tinnitus suppression. Two extradural Electrodes were subsequently implanted, also based on auditory fMRI-guided navigation. Postoperatively the tinnitus has improved by 66.67% and progressively continues to improve for more than one year. Conclusion Focal extradural electrical stimulation of the dorsolateral prefrontal cortex at the area of Cortical plasticity is capable of suppressing contralateral tinnitus partially. TMS might be a possible method for noninvasive studies of surgical candidates for implantation of stimulating Electrodes for tinnitus suppression.
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magnetic and electrical stimulation of the auditory cortex for intractable tinnitus case report
Journal of Neurosurgery, 2004Co-Authors: Dirk De Ridder, Stefan Sunaert, Gert De Mulder, Vincent Walsh, Neil G Muggleton, Aage R MollerAbstract:√ Tinnitus is a distressing symptom that affects up to 15% of the population for whom no satisfactory treatment exists. The authors present a novel surgical approach for the treatment of intractable tinnitus, based on Cortical stimulation of the auditory cortex. Tinnitus can be considered an auditory phantom phenomenon similar to deafferentation pain, which is observed in the somatosensory system. Tinnitus is accompanied by a change in the tonotopic map of the auditory cortex. Furthermore, there is a highly positive association between the subjective intensity of the tinnitus and the amount of shift in tinnitus fre quency in the auditory cortex, that is, the amount of Cortical reorganization. This Cortical reorganization can be demonstrated by functional magnetic resonance (fMR) imaging. Transcranial magnetic stimulation (TMS) is a noninvasive method of activating or deactivating focal areas of the human brain. Linked to a navigation system that is guided by fMR images of the auditory system, TMS can suppress areas of Cortical plasticity. If it is successful in suppressing a patient’s tinnitus, this focal and temporary effect can be perpetualized by implanting a Cortical Electrode. A neuronavigation-based auditory fMR imaging‐guided TMS session was performed in a patient who suffered from tinnitus due to a cochlear nerve lesion. Complete suppression of the tinnitus was obtained. At a later time an extradural Electrode was implanted with the guidance of auditory fMR imaging navigation. Postoperatively, the patient’s tinnitus disappeared and remains absent 10 months later. Focal extradural electrical stimulation of the primary auditory cortex at the area of Cortical plasticity is capable of suppressing contralateral tinnitus completely. Transcranial magnetic stimulation may be an ideal method for noninvasive studies of surgical candidates in whom stimulating Electrodes might be implanted for tinnitus suppression.
Ryosuke Tomio - One of the best experts on this subject based on the ideXlab platform.
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Comparison of effectiveness between cork-screw and peg-screw Electrodes for transcranial motor evoked potential monitoring using the finite element method.
Surgical neurology international, 2016Co-Authors: Ryosuke Tomio, Takenori Akiyama, Takayuki Ohira, Kazunari YoshidaAbstract:Intraoperative monitoring of motor evoked potentials by transcranial electric stimulation is popular in neurosurgery for monitoring motor function preservation. Some authors have reported that the peg-screw Electrodes screwed into the skull can more effectively conduct current to the brain compared to subdermal cork-screw Electrodes screwed into the skin. The aim of this study was to investigate the influence of Electrode design on transcranial motor evoked potential monitoring. We estimated differences in effectiveness between the cork-screw Electrode, peg-screw Electrode, and Cortical Electrode to produce electric fields in the brain. We used the finite element method to visualize electric fields in the brain generated by transcranial electric stimulation using realistic three-dimensional head models developed from T1-weighted images. Surfaces from five layers of the head were separated as accurately as possible. We created the "cork-screws model," "1 peg-screw model," "peg-screws model," and "Cortical Electrode model". Electric fields in the brain radially diffused from the brain surface at a maximum just below the Electrodes in coronal sections. The coronal sections and surface views of the brain showed higher electric field distributions under the peg-screw compared to the cork-screw. An extremely high electric field was observed under Cortical Electrodes. Our main finding was that the intensity of electric fields in the brain are higher in the peg-screw model than the cork-screw model.
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Comparison of effectiveness between cork-screw and peg-screw Electrodes for transcranial motor evoked potential monitoring using the finite element method
Surgical Neurology International, 2016Co-Authors: Ryosuke Tomio, Takenori Akiyama, Takayuki Ohira, Kazunari YoshidaAbstract:BACKGROUND Intraoperative monitoring of motor evoked potentials by transcranial electric stimulation is popular in neurosurgery for monitoring motor function preservation. Some authors have reported that the peg-screw Electrodes screwed into the skull can more effectively conduct current to the brain compared to subdermal cork-screw Electrodes screwed into the skin. The aim of this study was to investigate the influence of Electrode design on transcranial motor evoked potential monitoring. We estimated differences in effectiveness between the cork-screw Electrode, peg-screw Electrode, and Cortical Electrode to produce electric fields in the brain. METHODS We used the finite element method to visualize electric fields in the brain generated by transcranial electric stimulation using realistic three-dimensional head models developed from T1-weighted images. Surfaces from five layers of the head were separated as accurately as possible. We created the "cork-screws model," "1 peg-screw model," "peg-screws model," and "Cortical Electrode model". RESULTS Electric fields in the brain radially diffused from the brain surface at a maximum just below the Electrodes in coronal sections. The coronal sections and surface views of the brain showed higher electric field distributions under the peg-screw compared to the cork-screw. An extremely high electric field was observed under Cortical Electrodes. CONCLUSION Our main finding was that the intensity of electric fields in the brain are higher in the peg-screw model than the cork-screw model.
Dirk De Ridder - One of the best experts on this subject based on the ideXlab platform.
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Dorsolateral prefrontal cortex transcranial magnetic stimulation and Electrode implant for intractable tinnitus.
World neurosurgery, 2011Co-Authors: Dirk De Ridder, Sven Vanneste, Mark Plazier, Tomas Menovsky, Paul Van De Heyning, Silvia Kovacs, Stefan SunaertAbstract:Tinnitus is a distressing symptom that affects up to 15% of the population; no satisfactory treatment exists. We present a novel surgical approach for the treatment of intractable tinnitus based on electrical extradural stimulation of the dorsolateral prefrontal cortex via an Electrode implant. Tinnitus can be considered an auditory phantom phenomenon similar to deafferentation pain in the somatosensory system. It is characterized by gamma-band activity in the frontal cortex that can be visualized with the use of electroencephalography, magnetoencephalography, and functional magnetic resonance imaging (fMRI). Transcranial magnetic stimulation (TMS) is a noninvasive technique capable of modulating the ongoing activity of the human brain. When linked with a neuronavigation system, fMRI-guided frontal cortex TMS can be performed in a placebo-controlled way. If it is successful in suppressing tinnitus, this focal and temporary effect can be maintained in perpetuity by implanting a Cortical Electrode. A neuronavigation-based auditory fMRI-guided frontal cortex TMS session was performed in a patient experiencing intractable tinnitus, yielding 50% tinnitus suppression. Two extradural Electrodes were subsequently implanted, also based on auditory fMRI-guided navigation. Postoperatively the tinnitus has improved by 66.67% and progressively continues to improve for more than one year. Focal extradural electrical stimulation of the dorsolateral prefrontal cortex at the area of Cortical plasticity is capable of suppressing contralateral tinnitus partially. TMS might be a possible method for noninvasive studies of surgical candidates for implantation of stimulating Electrodes for tinnitus suppression. Copyright © 2012 Elsevier Inc. All rights reserved.
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Dorsolateral prefrontal cortex transcranial magnetic stimulation and Electrode implant for intractable tinnitus.
World Neurosurgery, 2011Co-Authors: Dirk De Ridder, Sven Vanneste, Mark Plazier, Tomas Menovsky, Paul Van De Heyning, Silvia Kovacs, Stefan SunaertAbstract:Objective Tinnitus is a distressing symptom that affects up to 15% of the population; no satisfactory treatment exists. We present a novel surgical approach for the treatment of intractable tinnitus based on electrical extradural stimulation of the dorsolateral prefrontal cortex via an Electrode implant. Tinnitus can be considered an auditory phantom phenomenon similar to deafferentation pain in the somatosensory system. It is characterized by gamma-band activity in the frontal cortex that can be visualized with the use of electroencephalography, magnetoencephalography, and functional magnetic resonance imaging (fMRI). Case Description Transcranial magnetic stimulation (TMS) is a noninvasive technique capable of modulating the ongoing activity of the human brain. When linked with a neuronavigation system, fMRI-guided frontal cortex TMS can be performed in a placebo-controlled way. If it is successful in suppressing tinnitus, this focal and temporary effect can be maintained in perpetuity by implanting a Cortical Electrode. A neuronavigation-based auditory fMRI-guided frontal cortex TMS session was performed in a patient experiencing intractable tinnitus, yielding 50% tinnitus suppression. Two extradural Electrodes were subsequently implanted, also based on auditory fMRI-guided navigation. Postoperatively the tinnitus has improved by 66.67% and progressively continues to improve for more than one year. Conclusion Focal extradural electrical stimulation of the dorsolateral prefrontal cortex at the area of Cortical plasticity is capable of suppressing contralateral tinnitus partially. TMS might be a possible method for noninvasive studies of surgical candidates for implantation of stimulating Electrodes for tinnitus suppression.
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magnetic and electrical stimulation of the auditory cortex for intractable tinnitus case report
Journal of Neurosurgery, 2004Co-Authors: Dirk De Ridder, Stefan Sunaert, Gert De Mulder, Vincent Walsh, Neil G Muggleton, Aage R MollerAbstract:√ Tinnitus is a distressing symptom that affects up to 15% of the population for whom no satisfactory treatment exists. The authors present a novel surgical approach for the treatment of intractable tinnitus, based on Cortical stimulation of the auditory cortex. Tinnitus can be considered an auditory phantom phenomenon similar to deafferentation pain, which is observed in the somatosensory system. Tinnitus is accompanied by a change in the tonotopic map of the auditory cortex. Furthermore, there is a highly positive association between the subjective intensity of the tinnitus and the amount of shift in tinnitus fre quency in the auditory cortex, that is, the amount of Cortical reorganization. This Cortical reorganization can be demonstrated by functional magnetic resonance (fMR) imaging. Transcranial magnetic stimulation (TMS) is a noninvasive method of activating or deactivating focal areas of the human brain. Linked to a navigation system that is guided by fMR images of the auditory system, TMS can suppress areas of Cortical plasticity. If it is successful in suppressing a patient’s tinnitus, this focal and temporary effect can be perpetualized by implanting a Cortical Electrode. A neuronavigation-based auditory fMR imaging‐guided TMS session was performed in a patient who suffered from tinnitus due to a cochlear nerve lesion. Complete suppression of the tinnitus was obtained. At a later time an extradural Electrode was implanted with the guidance of auditory fMR imaging navigation. Postoperatively, the patient’s tinnitus disappeared and remains absent 10 months later. Focal extradural electrical stimulation of the primary auditory cortex at the area of Cortical plasticity is capable of suppressing contralateral tinnitus completely. Transcranial magnetic stimulation may be an ideal method for noninvasive studies of surgical candidates in whom stimulating Electrodes might be implanted for tinnitus suppression.
Takayuki Ohira - One of the best experts on this subject based on the ideXlab platform.
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Comparison of effectiveness between cork-screw and peg-screw Electrodes for transcranial motor evoked potential monitoring using the finite element method.
Surgical neurology international, 2016Co-Authors: Ryosuke Tomio, Takenori Akiyama, Takayuki Ohira, Kazunari YoshidaAbstract:Intraoperative monitoring of motor evoked potentials by transcranial electric stimulation is popular in neurosurgery for monitoring motor function preservation. Some authors have reported that the peg-screw Electrodes screwed into the skull can more effectively conduct current to the brain compared to subdermal cork-screw Electrodes screwed into the skin. The aim of this study was to investigate the influence of Electrode design on transcranial motor evoked potential monitoring. We estimated differences in effectiveness between the cork-screw Electrode, peg-screw Electrode, and Cortical Electrode to produce electric fields in the brain. We used the finite element method to visualize electric fields in the brain generated by transcranial electric stimulation using realistic three-dimensional head models developed from T1-weighted images. Surfaces from five layers of the head were separated as accurately as possible. We created the "cork-screws model," "1 peg-screw model," "peg-screws model," and "Cortical Electrode model". Electric fields in the brain radially diffused from the brain surface at a maximum just below the Electrodes in coronal sections. The coronal sections and surface views of the brain showed higher electric field distributions under the peg-screw compared to the cork-screw. An extremely high electric field was observed under Cortical Electrodes. Our main finding was that the intensity of electric fields in the brain are higher in the peg-screw model than the cork-screw model.
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Comparison of effectiveness between cork-screw and peg-screw Electrodes for transcranial motor evoked potential monitoring using the finite element method
Surgical Neurology International, 2016Co-Authors: Ryosuke Tomio, Takenori Akiyama, Takayuki Ohira, Kazunari YoshidaAbstract:BACKGROUND Intraoperative monitoring of motor evoked potentials by transcranial electric stimulation is popular in neurosurgery for monitoring motor function preservation. Some authors have reported that the peg-screw Electrodes screwed into the skull can more effectively conduct current to the brain compared to subdermal cork-screw Electrodes screwed into the skin. The aim of this study was to investigate the influence of Electrode design on transcranial motor evoked potential monitoring. We estimated differences in effectiveness between the cork-screw Electrode, peg-screw Electrode, and Cortical Electrode to produce electric fields in the brain. METHODS We used the finite element method to visualize electric fields in the brain generated by transcranial electric stimulation using realistic three-dimensional head models developed from T1-weighted images. Surfaces from five layers of the head were separated as accurately as possible. We created the "cork-screws model," "1 peg-screw model," "peg-screws model," and "Cortical Electrode model". RESULTS Electric fields in the brain radially diffused from the brain surface at a maximum just below the Electrodes in coronal sections. The coronal sections and surface views of the brain showed higher electric field distributions under the peg-screw compared to the cork-screw. An extremely high electric field was observed under Cortical Electrodes. CONCLUSION Our main finding was that the intensity of electric fields in the brain are higher in the peg-screw model than the cork-screw model.
