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Richard B North - One of the best experts on this subject based on the ideXlab platform.

  • prevention of percutaneous spinal cord Stimulation Electrode migration a 15 year experience
    Neuromodulation, 2014
    Co-Authors: Richard B North, Violette Recinos, Frank J Attenello, Jane Shipley, Donlin M Long
    Abstract:

    Objectives Percutaneous spinal cord Stimulation Electrodes have a propensity to migrate longitudinally, which is a costly complication that often compromises therapeutic effect. After implementing simple changes to our percutaneous Electrode anchoring technique, we no longer encounter this migration. The current retrospective study updates previously reported results. Materials and Methods We retrospectively examined data in a consecutive series of patients in whom we had secured a new percutaneous Electrode by injecting < 0.1 cm3 of adhesive into the silicone elastomer lead anchor. From 1998 through 2006, we used whichever anchor was supplied with each lead until we observed one case of migration through a short anchor; thereafter, we used a long, tapered anchor exclusively. From 2007 through 2013, we further modified our technique by adding a fascial incision to accommodate the tip of the anchor and by increasing the strength of our suture material. Results In the first series of 291 patients, followed through July 2007 (mean 4.75 years, range 1.1–9.0 years), 4 (1.37%) experienced Electrode migration requiring surgical revision. Only one lead had moved with respect to its anchor; the other three anchors remained securely bonded to their leads. No migration (0.00%) occurred in the second series of 142 patients, followed through 2013 (mean follow-up 2.86 years, range 0.10–5.45 years). Conclusion Improvements to our simple, inexpensive technique apparently have eliminated the most common complication of spinal cord Stimulation.

  • spinal cord Stimulation Electrode design prospective randomized controlled trial comparing percutaneous and laminectomy Electrodes part i technical outcomes
    Neurosurgery, 2002
    Co-Authors: Richard B North, David H Kidd, John Olin, Jeffrey M Sieracki
    Abstract:

    OBJECTIVE The clinical use of spinal cord Stimulation for treatment of chronic intractable pain has been increasingly successful because of recent technical improvements, particularly the development of multiple-contact Electrodes supported by programmable implanted pulse generators. Contemporary el

Walter Paulus - One of the best experts on this subject based on the ideXlab platform.

  • Electrode distance dependent after effects of transcranial direct and random noise Stimulation with extracephalic reference Electrodes
    Clinical Neurophysiology, 2010
    Co-Authors: Vera Moliadze, Andrea Antal, Walter Paulus
    Abstract:

    Objective: To evaluate the importance of the distance between Stimulation Electrodes, in various montages, on the ability to induce sustained cortical excitability changes using transcranial direct and random noise Stimulation. Methods: Twelve healthy subjects participated in four different experimental conditions. The Stimulation Electrode was always placed over the primary motor cortex; the reference Electrode was placed at the contralateral orbit or at the ipsilateral/contralateral arm. MEPs were recorded in order to measure changes in cortical excitability over time. Results: The distance between the two Electrodes correlates negatively with the duration and magnitude of induced after-effects. Conclusions: In particular when using extracephalic reference Electrodes with transcranial electric Stimulation techniques, the Stimulation intensity has to be adapted to account for interElectrode distance. Significance: Electrode distance plays a critical role in the induction for Stimulation after effects in tDCS and tRNS studies, and must be taken into account in future studies and also when making comparisons with the published literature.

  • shaping the effects of transcranial direct current Stimulation of the human motor cortex
    Journal of Neurophysiology, 2007
    Co-Authors: Michael A Nitsche, S Doemkes, T Karakose, David Liebetanz, Frithjof Tergau, Andrea Antal, Nicolas Lang, Walter Paulus
    Abstract:

    Transcranial DC Stimulation (tDCS) induces Stimulation polarity-dependent neuroplastic excitability shifts in the human brain. Because it accomplishes long-lasting effects and its application is simple, it is used increasingly. However, one drawback is its low focality, caused by 1) the large Stimulation Electrode and 2) the functionally effective reference Electrode, which is also situated on the scalp. We aimed to increase the focality of tDCS, which might improve the interpretation of the functional effects of Stimulation because it will restrict its effects to more clearly defined cortical areas. Moreover, it will avoid unwanted reversed effects of tDCS under the reference Electrode, which is of special importance in clinical settings, when a homogeneous shift of cortical excitability is needed. Because current density (current strength/Electrode size) determines the efficacy of tDCS, increased focality should be accomplished by 1) reducing Stimulation Electrode size, but keeping current density constant; or 2) increasing reference Electrode size under constant current strength. We tested these hypotheses for motor cortex tDCS. The results show that reducing the size of the motor cortex DC-Stimulation Electrode focalized the respective tDCS-induced excitability changes. Increasing the size of the frontopolar reference Electrode rendered Stimulation over this cortex functionally inefficient, but did not compromise the tDCS-generated motor cortical excitability shifts. Thus tDCS-generated modulations of cortical excitability can be focused by reducing the size of the Stimulation Electrode and by increasing the size of the reference Electrode. For future applications of tDCS, such paradigms may help to achieve more selective tDCS effects.

Felipe Fregni - One of the best experts on this subject based on the ideXlab platform.

  • transcranial direct current Stimulation Electrode montage in stroke
    Disability and Rehabilitation, 2011
    Co-Authors: Hooman Mahmoudi, Afshin Borhani Haghighi, Peyman Petramfar, Sepehr Jahanshahi, Zahra Salehi, Felipe Fregni
    Abstract:

    Neurophysiological and computer modelling studies have shown that Electrode montage is a critical parameter to determine the neuromodulatory effects of transcranial direct current Stimulation (tDCS). We tested these results clinically by systematically investigating optimal tDCS Electrode montage in stroke. Ten patients received in a counterbalanced and randomised order the following conditions of Stimulation (i) anodal Stimulation of affected M1 (primary motor cortex) and cathodal Stimulation of unaffected M1 ('bilateral tDCS'); (ii) anodal Stimulation of affected M1 and cathodal Stimulation of contralateral supraorbital area ('anodal tDCS'); (iii) cathodal Stimulation of unaffected M1 and anodal Stimulation of contralateral supraorbital area ('cathodal tDCS'); (iv) anodal Stimulation of affected M1 and cathodal Stimulation of contralateral deltoid muscle ('extra-cephalic tDCS') and (v) sham Stimulation. We used the Jebsen-Taylor Test (JTT) as a widely accepted measure of upper limb function. Bilateral tDCS, anodal tDCS and cathodal tDCS were shown to be associated with significant improvements on the JTT. Placing the reference Electrode in an extracephalic position and use of sham Stimulation did not induce any significant effects. This small sham controlled cross-over clinical trial is important to provide additional data on the clinical effects of tDCS in stroke and for planning and designing future large tDCS trials in patients with stroke.

Jeffrey M Sieracki - One of the best experts on this subject based on the ideXlab platform.

Donlin M Long - One of the best experts on this subject based on the ideXlab platform.

  • prevention of percutaneous spinal cord Stimulation Electrode migration a 15 year experience
    Neuromodulation, 2014
    Co-Authors: Richard B North, Violette Recinos, Frank J Attenello, Jane Shipley, Donlin M Long
    Abstract:

    Objectives Percutaneous spinal cord Stimulation Electrodes have a propensity to migrate longitudinally, which is a costly complication that often compromises therapeutic effect. After implementing simple changes to our percutaneous Electrode anchoring technique, we no longer encounter this migration. The current retrospective study updates previously reported results. Materials and Methods We retrospectively examined data in a consecutive series of patients in whom we had secured a new percutaneous Electrode by injecting < 0.1 cm3 of adhesive into the silicone elastomer lead anchor. From 1998 through 2006, we used whichever anchor was supplied with each lead until we observed one case of migration through a short anchor; thereafter, we used a long, tapered anchor exclusively. From 2007 through 2013, we further modified our technique by adding a fascial incision to accommodate the tip of the anchor and by increasing the strength of our suture material. Results In the first series of 291 patients, followed through July 2007 (mean 4.75 years, range 1.1–9.0 years), 4 (1.37%) experienced Electrode migration requiring surgical revision. Only one lead had moved with respect to its anchor; the other three anchors remained securely bonded to their leads. No migration (0.00%) occurred in the second series of 142 patients, followed through 2013 (mean follow-up 2.86 years, range 0.10–5.45 years). Conclusion Improvements to our simple, inexpensive technique apparently have eliminated the most common complication of spinal cord Stimulation.