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Philip A Starr - One of the best experts on this subject based on the ideXlab platform.
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magnetic resonance imaging of implanted Deep Brain Stimulators experience in a large series
Stereotactic and Functional Neurosurgery, 2008Co-Authors: Paul S Larson, R M Richardson, Philip A Starr, Alastair J MartinAbstract:Magnetic resonance imaging (MRI) is a commonly used and important imaging modality to evaluate lead location and rule out complications after Deep Brain stimulation (DBS) surgery. Recent safety concerns have prompted new safety recommendations for the use of MRI in these patients, including a new recommendation to limit the specific absorption rate (SAR) of the MRI sequences used to less than 0.1 W/kg. Following SAR recommendations in real-world situations is problematic for a variety of reasons. We review our experience scanning patients with implanted DBS systems over a 7-year period using a variety of scanning techniques and four scanning platforms. 405 patients with 746 implanted DBS systems were imaged using 1.5-tesla MRI with an SAR of up to 3 W/kg. Many of the DBS systems were imaged multiple times, for a total of 1,071 MRI events in this group of patients with no adverse events. This series strongly suggests that the 0.1 W/kg recommendation for SAR may be unnecessarily low for the prevention of MRI-related adverse events.
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microelectrode guided implantation of Deep Brain Stimulators into the globus pallidus internus for dystonia techniques electrode locations and outcomes
Journal of Neurosurgery, 2006Co-Authors: Philip A Starr, Nadja Lindsey, Robert S Turner, Geoff Rau, Susan Heath, Monica Volz, Jill L Ostrem, William J MarksAbstract:Object. Deep Brain stimulation (DBS) of the globus pallidus internus (GPI) is a promising new procedure for the treatment of dystonia. The authors describe their technical approach for placing electrodes into the GPI in awake patients with dystonia, including methodology for electrophysiological mapping of the GPI in the dystonic state, clinical outcomes and complications, and the location of electrodes associated with optimal benefit. Methods. Twenty-three adult and pediatric patients with various forms of dystonia were included in this study. Baseline neurological status and DBS-related improvement in motor function were measured using the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS). The implantation of DBS leads was performed using magnetic resonance (MR) imaging-based stereotaxy, single-cell microelectrode recording, and intraoperative test stimulation to determine thresholds for stimulation-induced adverse effects. Electrode locations were measured on computationally reformatted postoperative MR images according to a prospective protocol. Conclusions. Physiologically guided implantation of DBS electrodes in patients with dystonia was technically feasible in the awake state in most patients, and the morbidity rate was low. Spontaneous discharge rates of GPI neurons in dystonia were similar to those of globus pallidus externus neurons, such that the two nuclei must be distinguished by neuronal discharge patterns rather than rates. Active electrode locations associated with robust improvement (> 70% decrease in BFMDRS score) were located near the intercommissural plane, at a mean distance from the pallidocapsular border of 3.6 mm.
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microelectrode guided implantation of Deep Brain Stimulators into the globus pallidus internus for dystonia techniques electrode locations and outcomes
Neurosurgical Focus, 2004Co-Authors: Philip A Starr, Nadja Lindsey, Robert S Turner, Geoff Rau, Susan Heath, Monica Volz, Jill L Ostrem, William J MarksAbstract:Object Deep Brain stimulation (DBS) of the globus pallidus internus (GPI) is a promising new procedure for the treatment of dystonia. The authors describe their technical approach for placing electrodes into the GPI in awake patients with dystonia, including methodology for electrophysiological mapping of the GPI in the dystonic state, clinical outcomes and complications, and the location of electrodes associated with optimal benefit. Methods Twenty-three adult and pediatric patients with various forms of dystonia were included in this study. Baseline neurological status and DBS-related improvement in motor function were measured using the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS). The implantation of DBS leads was performed using magnetic resonance (MR) imaging–based stereotaxy, single-cell microelectrode recording, and intraoperative test stimulation to determine thresholds for stimulation-induced adverse effects. Electrode locations were measured on computationally reformatted postoperative MR ...
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implantation of Deep Brain Stimulators into the subthalamic nucleus technical approach and magnetic resonance imaging verified lead locations
Journal of Neurosurgery, 2002Co-Authors: Philip A Starr, Chadwick W Christine, Philip V Theodosopoulos, Nadja Lindsey, Deborah Byrd, Anthony Mosley, William J MarksAbstract:Object. Chronic Deep Brain stimulation (DBS) of the subthalamic nucleus (STN) is a procedure that is rapidly gaining acceptance for the treatment of symptoms in patients with Parkinson disease (PD), but there are few detailed descriptions of the surgical procedure itself. The authors present the technical approach used to implant 76 Stimulators into the STNs of patients with PD and the lead locations, which were verified on postoperative magnetic resonance (MR) images. Methods. Implantation procedures were performed with the aid of stereotactic MR imaging, microelectrode recording (MER) in the region of the stereotactic target to define the motor area of the STN, and intraoperative test stimulation to assess the thresholds for stimulation-induced adverse effects. All patients underwent postoperative MR imaging, which was performed using volumetric gradient-echo and T2-weighted fast—spin echo techniques, computational reformatting of the MR image into standard anatomical planes, and quantitative measuremen...
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placement of Deep Brain Stimulators into the subthalamic nucleus or globus pallidus internus technical approach
Stereotactic and Functional Neurosurgery, 2002Co-Authors: Philip A StarrAbstract:Deep Brain stimulation (DBS) represents a major advance in the treatment of Parkinson's disease (PD). As more neurosurgeons enter this field, technical descriptions of implantation techniques are needed. Here we present our technical approach to subthalamic nucleus (STN) and globus pallidus internus (GPi) DBS implantation, based on 180 STN implants and 75 GPi implants. The essential steps in DBS implantation are magnetic resonance imaging (MRI)-guided stereotactic localization, confirmation of the motor territory of the target nucleus with microelectrode mapping, and intra-operative test stimulation to determine voltage thresholds for stimulation-induced adverse effects. Lead locations are documented by postoperative MRI in all cases.
David J. Mikulis - One of the best experts on this subject based on the ideXlab platform.
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Thalamic stimulation and functional magnetic resonance imaging: localization of cortical and subcortical activation with implanted electrodes. Technical note.
Journal of Neurosurgery, 1999Co-Authors: Ali R Rezai, Ronald R. Tasker, Adrian P. Crawley, Chun L Kwan, Andres M Lozano, Jonathan O. Dostrovsky, Karen D Davis, David J. MikulisAbstract:✓ The utility of functional magnetic resonance (fMR) imaging in patients with implanted thalamic electrodes has not yet been determined. The aim of this study was to establish the safety of performing fMR imaging in patients with thalamic Deep Brain Stimulators and to determine the value of fMR imaging in detecting cortical and subcortical activity during stimulation. Functional MR imaging was performed in three patients suffering from chronic pain and two patients with essential tremor. Two of the three patients with pain had undergone electrode implantation in the thalamic sensory ventralis caudalis (Vc) nucleus and the other had undergone electrode implantation in both the Vc and the periventricular gray (PVG) matter. Patients with tremor underwent electrode implantation in the ventralis intermedius (Vim) nucleus. Functional MR imaging was performed during stimulation by using a pulse generator connected to a transcutaneous extension lead. Clinically, Vc stimulation evoked paresthesias in the contralat...
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Thalamic stimulation and functional magnetic resonance imaging: localization of cortical and subcortical activation with implanted electrodes: Technical note
Neurosurgical Focus, 1999Co-Authors: Ali R Rezai, Ronald R. Tasker, Adrian P. Crawley, Chun L Kwan, Andres M Lozano, Jonathan O. Dostrovsky, Karen D Davis, David J. MikulisAbstract:The utility of functional magnetic resonance (fMR) imaging in patients with implanted thalamic electrodes has not yet been determined. The aim of this study was to establish the safety of performing fMR imaging in patients with thalamic Deep Brain Stimulators and to determine the value of fMR imaging in detecting cortical and subcortical activity during stimulation. Functional MR imaging was performed in three patients suffering from chronic pain and two patients with essential tremor. Two of the three patients with pain had undergone electrode implantation in the thalamic sensory ventralis caudalis (Vc) nucleus and the other had undergone electrode implantation in both the Vc and the periventricular gray (PVG) matter. Patients with tremor underwent electrode implantation in the ventralis intermedius (Vim) nucleus. Functional MR imaging was performed during stimulation by using a pulse generator connected to a transcutaneous extension lead. Clinically, Vc stimulation evoked paresthesias in the contralateral body, PVG stimulation evoked a sensation of diffuse internal body warmth, and Vim stimulation caused tremor arrest. Functional images were acquired using a 1.5-tesla MR imaging system. The Vc stimulation at intensities provoking paresthesias resulted in activation of the primary somatosensory cortex (SI). Stimulation at subthreshold intensities failed to activate the SI. Additional stimulation-coupled activation was observed in the thalamus, the secondary somatosensory cortex (SII), and the insula. In contrast, stimulation of the PVG electrode did not evoke paresthesias or activate the SI, but resulted in medial thalamic and cingulate cortex activation. Stimulation in the Vim resulted in thalamic, basal ganglia, and SI activation. An evaluation of the safety of the procedure indicated that significant current could be induced within the electrode if a faulty connecting cable (defective insulation) came in contact with the patient. Simple precautions, such as inspection of wires for fraying and prevention of their contact with the patient, enabled the procedure to be conducted safely. Clinical safety was further corroborated by performing 86 MR studies in patients in whom electrodes had been implanted with no adverse clinical effects. This is the first report of the use of fMR imaging during stimulation with implanted thalamic electrodes. The authors' findings demonstrate that fMR imaging can safely detect the activation of cortical and subcortical neuronal pathways during stimulation and that stimulation does not interfere with imaging. This approach offers great potential for understanding the mechanisms of action of Deep Brain stimulation and those underlying pain and tremor generation.
William J Marks - One of the best experts on this subject based on the ideXlab platform.
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microelectrode guided implantation of Deep Brain Stimulators into the globus pallidus internus for dystonia techniques electrode locations and outcomes
Journal of Neurosurgery, 2006Co-Authors: Philip A Starr, Nadja Lindsey, Robert S Turner, Geoff Rau, Susan Heath, Monica Volz, Jill L Ostrem, William J MarksAbstract:Object. Deep Brain stimulation (DBS) of the globus pallidus internus (GPI) is a promising new procedure for the treatment of dystonia. The authors describe their technical approach for placing electrodes into the GPI in awake patients with dystonia, including methodology for electrophysiological mapping of the GPI in the dystonic state, clinical outcomes and complications, and the location of electrodes associated with optimal benefit. Methods. Twenty-three adult and pediatric patients with various forms of dystonia were included in this study. Baseline neurological status and DBS-related improvement in motor function were measured using the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS). The implantation of DBS leads was performed using magnetic resonance (MR) imaging-based stereotaxy, single-cell microelectrode recording, and intraoperative test stimulation to determine thresholds for stimulation-induced adverse effects. Electrode locations were measured on computationally reformatted postoperative MR images according to a prospective protocol. Conclusions. Physiologically guided implantation of DBS electrodes in patients with dystonia was technically feasible in the awake state in most patients, and the morbidity rate was low. Spontaneous discharge rates of GPI neurons in dystonia were similar to those of globus pallidus externus neurons, such that the two nuclei must be distinguished by neuronal discharge patterns rather than rates. Active electrode locations associated with robust improvement (> 70% decrease in BFMDRS score) were located near the intercommissural plane, at a mean distance from the pallidocapsular border of 3.6 mm.
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microelectrode guided implantation of Deep Brain Stimulators into the globus pallidus internus for dystonia techniques electrode locations and outcomes
Neurosurgical Focus, 2004Co-Authors: Philip A Starr, Nadja Lindsey, Robert S Turner, Geoff Rau, Susan Heath, Monica Volz, Jill L Ostrem, William J MarksAbstract:Object Deep Brain stimulation (DBS) of the globus pallidus internus (GPI) is a promising new procedure for the treatment of dystonia. The authors describe their technical approach for placing electrodes into the GPI in awake patients with dystonia, including methodology for electrophysiological mapping of the GPI in the dystonic state, clinical outcomes and complications, and the location of electrodes associated with optimal benefit. Methods Twenty-three adult and pediatric patients with various forms of dystonia were included in this study. Baseline neurological status and DBS-related improvement in motor function were measured using the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS). The implantation of DBS leads was performed using magnetic resonance (MR) imaging–based stereotaxy, single-cell microelectrode recording, and intraoperative test stimulation to determine thresholds for stimulation-induced adverse effects. Electrode locations were measured on computationally reformatted postoperative MR ...
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implantation of Deep Brain Stimulators into the subthalamic nucleus technical approach and magnetic resonance imaging verified lead locations
Journal of Neurosurgery, 2002Co-Authors: Philip A Starr, Chadwick W Christine, Philip V Theodosopoulos, Nadja Lindsey, Deborah Byrd, Anthony Mosley, William J MarksAbstract:Object. Chronic Deep Brain stimulation (DBS) of the subthalamic nucleus (STN) is a procedure that is rapidly gaining acceptance for the treatment of symptoms in patients with Parkinson disease (PD), but there are few detailed descriptions of the surgical procedure itself. The authors present the technical approach used to implant 76 Stimulators into the STNs of patients with PD and the lead locations, which were verified on postoperative magnetic resonance (MR) images. Methods. Implantation procedures were performed with the aid of stereotactic MR imaging, microelectrode recording (MER) in the region of the stereotactic target to define the motor area of the STN, and intraoperative test stimulation to assess the thresholds for stimulation-induced adverse effects. All patients underwent postoperative MR imaging, which was performed using volumetric gradient-echo and T2-weighted fast—spin echo techniques, computational reformatting of the MR image into standard anatomical planes, and quantitative measuremen...
Ali R Rezai - One of the best experts on this subject based on the ideXlab platform.
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Thalamic stimulation and functional magnetic resonance imaging: localization of cortical and subcortical activation with implanted electrodes. Technical note.
Journal of Neurosurgery, 1999Co-Authors: Ali R Rezai, Ronald R. Tasker, Adrian P. Crawley, Chun L Kwan, Andres M Lozano, Jonathan O. Dostrovsky, Karen D Davis, David J. MikulisAbstract:✓ The utility of functional magnetic resonance (fMR) imaging in patients with implanted thalamic electrodes has not yet been determined. The aim of this study was to establish the safety of performing fMR imaging in patients with thalamic Deep Brain Stimulators and to determine the value of fMR imaging in detecting cortical and subcortical activity during stimulation. Functional MR imaging was performed in three patients suffering from chronic pain and two patients with essential tremor. Two of the three patients with pain had undergone electrode implantation in the thalamic sensory ventralis caudalis (Vc) nucleus and the other had undergone electrode implantation in both the Vc and the periventricular gray (PVG) matter. Patients with tremor underwent electrode implantation in the ventralis intermedius (Vim) nucleus. Functional MR imaging was performed during stimulation by using a pulse generator connected to a transcutaneous extension lead. Clinically, Vc stimulation evoked paresthesias in the contralat...
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Thalamic stimulation and functional magnetic resonance imaging: localization of cortical and subcortical activation with implanted electrodes: Technical note
Neurosurgical Focus, 1999Co-Authors: Ali R Rezai, Ronald R. Tasker, Adrian P. Crawley, Chun L Kwan, Andres M Lozano, Jonathan O. Dostrovsky, Karen D Davis, David J. MikulisAbstract:The utility of functional magnetic resonance (fMR) imaging in patients with implanted thalamic electrodes has not yet been determined. The aim of this study was to establish the safety of performing fMR imaging in patients with thalamic Deep Brain Stimulators and to determine the value of fMR imaging in detecting cortical and subcortical activity during stimulation. Functional MR imaging was performed in three patients suffering from chronic pain and two patients with essential tremor. Two of the three patients with pain had undergone electrode implantation in the thalamic sensory ventralis caudalis (Vc) nucleus and the other had undergone electrode implantation in both the Vc and the periventricular gray (PVG) matter. Patients with tremor underwent electrode implantation in the ventralis intermedius (Vim) nucleus. Functional MR imaging was performed during stimulation by using a pulse generator connected to a transcutaneous extension lead. Clinically, Vc stimulation evoked paresthesias in the contralateral body, PVG stimulation evoked a sensation of diffuse internal body warmth, and Vim stimulation caused tremor arrest. Functional images were acquired using a 1.5-tesla MR imaging system. The Vc stimulation at intensities provoking paresthesias resulted in activation of the primary somatosensory cortex (SI). Stimulation at subthreshold intensities failed to activate the SI. Additional stimulation-coupled activation was observed in the thalamus, the secondary somatosensory cortex (SII), and the insula. In contrast, stimulation of the PVG electrode did not evoke paresthesias or activate the SI, but resulted in medial thalamic and cingulate cortex activation. Stimulation in the Vim resulted in thalamic, basal ganglia, and SI activation. An evaluation of the safety of the procedure indicated that significant current could be induced within the electrode if a faulty connecting cable (defective insulation) came in contact with the patient. Simple precautions, such as inspection of wires for fraying and prevention of their contact with the patient, enabled the procedure to be conducted safely. Clinical safety was further corroborated by performing 86 MR studies in patients in whom electrodes had been implanted with no adverse clinical effects. This is the first report of the use of fMR imaging during stimulation with implanted thalamic electrodes. The authors' findings demonstrate that fMR imaging can safely detect the activation of cortical and subcortical neuronal pathways during stimulation and that stimulation does not interfere with imaging. This approach offers great potential for understanding the mechanisms of action of Deep Brain stimulation and those underlying pain and tremor generation.
Gordon H Baltuch - One of the best experts on this subject based on the ideXlab platform.
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use of an integrated platform system in the placement of Deep Brain Stimulators
Neurosurgery, 2008Co-Authors: Gregory G Heuer, Kareem A Zaghloul, Jurg L Jaggi, Gordon H BaltuchAbstract:The placement of Deep Brain stimulator leads requires a great deal of technology and equipment. We describe our 25-month experience with an integrated platform system, the StimPilot (Medtronic Inc., Minneapolis, MN), for the placement of Deep Brain stimulator leads. The platform consists of a neuronavigation station, microdrive control, and microelectrode recording display and control. This platform is run from a laptop-sized portable control unit. The unit was used in 147 patients for the placement of 262 leads. Leads were placed into the subthalamic nucleus, ventral intermediate nucleus, globus pallidus interna, and anterior thalamic nucleus. One patient required replacement of one lead during this time frame, with successful reimplantation. No system failures occurred.
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Deep Brain stimulation for Parkinson's disease /
2007Co-Authors: Gordon H Baltuch, Matthew B. SternAbstract:The History of Deep Brain Stimulation. DBS: Anatomical, Physiological, and Computational Mechanisms. Indications for Subthalamic Nucleus DBS Surgery. Pre-op Assessment and Teaching. Surgical Technique for Leksell-Frame Based DBS of the Subthalamic Nucleus. Frameless Stereotaxy for Placement of Deep Brain Stimulators. Neurophysiology of the Microelectrode Track during Subthalamic Nucleus and Globus Pallidus Internus Targeting. Complications and Avoidance. Programming DBS. Medication Adjustment After DBS Surgery of the Subthalamic Nucleus. Rehabilitation after DBS. DBS of the Subthalamic Nucleus. DBS for Parkinson's Disease. Subthalamic Nucleus DBS and Nonmotor Symptoms of Parkinson's Disease. Neuropsychology of DBS in Parkinson's Disease. Neuropsychiatric Complications and DBS in Parkinson's Disease. Quality-of-Life Outcomes Following Stereotactic Surgery for Parkinson's Disease. Conducting Clinical Trials of DBS in Parkinson's Disease. Ethical Issues in DBS.
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electroconvulsive therapy for depression in a parkinson s disease patient with bilateral subthalamic nucleus Deep Brain Stimulators
Parkinsonism & Related Disorders, 2005Co-Authors: Kelvin L Chou, Jurg L Jaggi, Gordon H Baltuch, Howard I Hurtig, Rodney J Pelchat, Daniel WeintraubAbstract:We report a patient with advanced Parkinson's disease (PD) who developed a recurrence of major depression with psychotic features after bilateral subthalamic nucleus (STN) Deep Brain stimulation (DBS) surgery. Electroconvulsive therapy (ECT) dramatically improved the depression without shifting electrode position or damaging the DBS hardware. This case suggests that ECT can be a safe and effective option for severe depression in PD patients treated with STN DBS.
