Neuromodulation : journal of the International Neuromodulation Society
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Objective. This study assessed 3-Tesla magnetic resonance imaging (MRI) issues for a programmable infusion pump and associated catheters. Methods. A programmable infusion pump and associated catheters (MedStream Programmable Infusion Pump, 40 mL; SureStream TI Coil-Reinforced Intraspinal Catheter; SureStream TI Connector; and SureStream Silicone Catheter; Codman and Shurtleff Inc., a Johnson & Johnson Company, Raynham, MA, USA) underwent evaluation for magnetic field interactions (deflection angle and torque), heating (transmit/receive body radiofrequency coil; whole-body averaged specific absorption rate, 3 W/kg for 15 min), functional changes (before and after MRI using eight different MRI conditions), and artifacts (T1-weighted spin-echo and gradient-echo pulse sequences) at 3-Tesla. Results. The programmable infusion pump and associated catheters exhibited minor magnetic field interactions. ⋯ Artifacts were relatively large for the pump and minor for the catheter. Conclusions. The programmable infusion pump and catheters will not pose increased risk to a patient examined using 3-Tesla MRI as long as specific safety guidelines are followed, which includes interrogation of the pump post-MRI to ensure proper settings. Artifacts for the programmable infusion pump may impact the diagnostic use of MRI if the area of interest is in the same area or near the device.
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Objectives. Motor cortex stimulation has been used as a treatment for intractable pain. However, the mechanisms underlying its effects remain unclear. In this study, neuroplasticity induced by chronic sensorimotor cortex stimulation was investigated experimentally on the basis of c-Fos expression. ⋯ We examined the neural activation in response to chronic stimulation using c-Fos immunopositivity. Results. The results are as follows: 1) c-Fos was significantly expressed immediately after the stimulation compared with that in the control; 2) c-Fos expression became extensive over the various regions with an increase in stimulation duration; and 3) after two months of stimulation, c-Fos was expressed not only on the stimulation side, but also within the contralateral cerebral hemisphere. Conclusions. Changes in c-Fos expression induced by long-term stimulation indicate the existence of a time-dependent neural plasticity.
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Objective. In a randomized controlled trial comparing manual with automated computerized adjustment of spinal cord stimulators in patients with implanted power generators, automated adjustment conferred the following advantages: 1) more settings tested in a given time, 2) significantly greater pain/paresthesia overlap, 3) increased battery life, and 4) a $303,756 (95% confidence intervals = $116,503-491,009) reduction in lifetime per patient cost. The current study analyzes the sensitivity of this cost-savings to usage time/day, inflation, discount rate, and years of use. ⋯ This savings is attributable to increased battery life. Conclusion. Sensitivity analyzes reveal that the significant cost-savings achieved with computerized, patient-directed adjustment of spinal cord stimulation in selected patients with chronic pain is robust across a representative range of parameters.
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Objectives. This paper describes an experimental investigation of variable frequency stimulation patterns as a means of increasing torque production and, hence, performance in cycling induced by functional electrical stimulation. Materials and Methods. Experiments were conducted on six able-bodied subjects stimulating both quadriceps during isokinetic trials. Constant-frequency trains (CFT) with 50-msec interpulse intervals and four catchlike-inducing trains (CIT) were tested. ⋯ Conclusions. The use of CITs improves the functional electrical stimulation cycling performance compared with CFT stimulation. This application might have a relevant clinical importance for individuals with stroke where the residual sensation is still present and thus the maximization of the performance without an excessive increase of the stimulation intensity is advisable. Therefore, exercise intensity can be increased yielding a better muscle strength and endurance that may be beneficially for later gait training in individuals with stroke.
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In neuromodulation treatment and research, the informed consent of the patient or research subject is considered to be a moral precondition. In order to be morally valid, the consent of the person should be informed and voluntarily given, and the person should have decision-making capacity. Decision-making capacity matters from a moral point of view because it enables the patient or research subject to make a well-considered decision about treatment or research participation. ⋯ In this paper, it is argued that full decision-making capacity in the context of neuromodulation is an illusion. This does not imply that we should do away with the moral ideals of decision-making capacity and valid informed consent. It is part of the responsibility of clinicians involved in neuromodulation to be aware of and sensitive to the different threats to the decision-making capacity of patients suffering from neurological and neuropsychiatric disorders, and to assist patients in making decisions that are as well considered as possible in the given circumstances.