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Poppendieck W, Hoffmann KP, Merfeld D, Guyot JP, Micera S. Ethical issues in the development of a vestibular prosthesis. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2011; 2011:2265-2268. [PMID: 22254792 DOI: 10.1109/iembs.2011.6090570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
During the development of a neural prosthesis, various ethical aspects have to be considered. These range from the basic design of the prosthesis and manufacturing of the various components and the system using biocompatible materials to extensive in vitro and in vivo testing and investigations in the animal model, before taking the final step and going to human trials. As medical systems, neural prostheses have to be proven absolutely safe before considering any clinical study. In this work, the various steps accompanying the development are described taking the example of a vestibular prosthesis currently developed within the European project CLONS.
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Affiliation(s)
- Wigand Poppendieck
- Fraunhofer Institute for Biomedical Engineering, Department Medical Engineering & Neuroprosthetics, 66386 St Ingbert, Germany.
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202
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Vannemreddy P, Slavin KV. Spinal cord stimulation: Current applications for treatment of chronic pain. Anesth Essays Res 2011; 5:20-7. [PMID: 25885295 PMCID: PMC4173369 DOI: 10.4103/0259-1162.84174] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Spinal cord stimulation (SCS) is thought to relieve chronic intractable pain by stimulating nerve fibers in the spinal cord. The resulting impulses in the fibers may inhibit the conduction of pain signals to the brain, according to the pain gate theory proposed by Melzack and Wall in 1965 and the sensation of pain is thus blocked. Although SCS may reduce pain, it will not eliminate it. After a period of concern about safety and efficacy, SCS is now regaining popularity among pain specialists for the treatment of chronic pain. The sympatholytic effect of SCS is one of its most interesting therapeutic properties. This effect is considered responsible for the effectiveness of SCS in peripheral ischemia, and at least some cases of complex regional pain syndrome. The sympatholytic effect has also been considered part of the management of other chronic pain states such as failed back surgery syndrome, phantom pain, diabetic neuropathy, and postherpetic neuralgia. In general, SCS is part of an overall treatment strategy and is used only after the more conservative treatments have failed. The concept of SCS has evolved rapidly following the technological advances that have produced leads with multiple contact electrodes and battery systems. The current prevalence of patients with chronic pain requiring treatment other than conventional medical management has significantly increased and so has been the need for SCS. With the cost benefit analysis showing significant support for SCS, it may be appropriate to offer this as an effective alternative treatment for these patients.
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Affiliation(s)
- Prasad Vannemreddy
- Department of Neurosurgery, University of Illinois at Chicago, Chicago, USA
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203
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Kones R. Recent advances in the management of chronic stable angina II. Anti-ischemic therapy, options for refractory angina, risk factor reduction, and revascularization. Vasc Health Risk Manag 2010; 6:749-74. [PMID: 20859545 PMCID: PMC2941787 DOI: 10.2147/vhrm.s11100] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2010] [Indexed: 12/19/2022] Open
Abstract
The objectives in treating angina are relief of pain and prevention of disease progression through risk reduction. Mechanisms, indications, clinical forms, doses, and side effects of the traditional antianginal agents - nitrates, β-blockers, and calcium channel blockers - are reviewed. A number of patients have contraindications or remain unrelieved from anginal discomfort with these drugs. Among newer alternatives, ranolazine, recently approved in the United States, indirectly prevents the intracellular calcium overload involved in cardiac ischemia and is a welcome addition to available treatments. None, however, are disease-modifying agents. Two options for refractory angina, enhanced external counterpulsation and spinal cord stimulation (SCS), are presented in detail. They are both well-studied and are effective means of treating at least some patients with this perplexing form of angina. Traditional modifiable risk factors for coronary artery disease (CAD) - smoking, hypertension, dyslipidemia, diabetes, and obesity - account for most of the population-attributable risk. Individual therapy of high-risk patients differs from population-wide efforts to prevent risk factors from appearing or reducing their severity, in order to lower the national burden of disease. Current American College of Cardiology/American Heart Association guidelines to lower risk in patients with chronic angina are reviewed. The Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) trial showed that in patients with stable angina, optimal medical therapy alone and percutaneous coronary intervention (PCI) with medical therapy were equal in preventing myocardial infarction and death. The integration of COURAGE results into current practice is discussed. For patients who are unstable, with very high risk, with left main coronary artery lesions, in whom medical therapy fails, and in those with acute coronary syndromes, PCI is indicated. Asymptomatic patients with CAD and those with stable angina may defer intervention without additional risk to see if they will improve on optimum medical therapy. For many patients, coronary artery bypass surgery offers the best opportunity for relieving angina, reducing the need for additional revascularization procedures and improving survival. Optimal medical therapy, percutaneous coronary intervention, and surgery are not competing therapies, but are complementary and form a continuum, each filling an important evidence-based need in modern comprehensive management.
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Affiliation(s)
- Richard Kones
- Cardiometabolic Research Institute, Houston, Texas 77055, USA.
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204
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Kim TH, Lee PB, Son HM, Choi JB, Moon JY. Spontaneous lead breakage in implanted spinal cord stimulation systems. Korean J Pain 2010; 23:78-81. [PMID: 20552080 PMCID: PMC2884218 DOI: 10.3344/kjp.2010.23.1.78] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2009] [Revised: 12/03/2009] [Accepted: 12/11/2009] [Indexed: 11/29/2022] Open
Abstract
Spinal cord stimulation (SCS) has become an established clinical option for treatment of refractory chronic pain. Current hardware and implantation techniques for SCS are already highly developed and continuously improving; however, equipment failures over the course of long-term treatment are still encountered in a relatively high proportion of the cases treated with it. Percutaneous SCS leads seem to be particularly prone to dislocation and insulation failures. We describe our experience of lead breakage in the inserted spinal cord stimulator to a complex regional pain syndrome patient who obtained satisfactory pain relief after the revision of SCS.
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Affiliation(s)
- Tae Hun Kim
- Department of Anesthesiology and Pain Medicine, Seoul National University School of Medicine, Seoul, Korea
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205
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Abstract
This case report presents the use of spinal cord stimulation (SCS) in a patient with urinary incontinence who had previously undergone trial and implantation of InterStim therapy (Medtronic Neurological, Minneapolis, MN). The patient also experienced bilateral lower extremity pain and low back pain related to post-laminectomy syndrome. Having failed all conservative treatment, the patient underwent SCS trial and subsequent implantation. In the postoperative period using SCS therapy, the patient had excellent relief of urinary incontinence symptoms, along with relief of low back pain and bilateral lower extremity pain and was able to discontinue use of InterStim therapy. For this patient, SCS was effective in controlling the urinary voiding dysfunction symptoms, bilateral lower extremity pain and back pain. The use of SCS to treat urinary incontinence problems deserves further study to explore its therapeutic potentials.
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Affiliation(s)
- Alexander E Yakovlev
- Comprehensive Pain Management of the Fox Valley, SC 820 East Grant Street Suite 335 Appleton, Wisconsin 54911, USA.
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206
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Kim JK, Hong SH, Lee JK. High-level cervical spinal cord stimulation used to treat intractable pain arising from transverse myelitis caused by schistosomiasis. J Korean Neurosurg Soc 2010; 47:151-4. [PMID: 20224718 DOI: 10.3340/jkns.2010.47.2.151] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2009] [Revised: 07/16/2009] [Accepted: 12/27/2009] [Indexed: 11/27/2022] Open
Abstract
The efficacy of spinal cord stimulation (SCS) for treatment of various chronic painful conditions is well established. Very few reports have documented the use of SCS for treatment of chronic pain after spinal cord injury. We present a case showing a good outcome after such treatment, and suggest that high cervical stimulation may be efficacious. A 53-year-old male underwent SCS on the C1-3 level for treatment of intractable neuropathic pain below the T3 level, and in the upper extremities, arising from spinal cord injury resulting from transverse myelitis caused by schistosomiasis. High cervical SCS significantly improved the pain in the upper extremities and at the T3-T10 dermatome level. The patient continues to report excellent pain relief 9 months later. The present case suggests that high cervical stimulation may improve chronic pain in the upper extremities and the T3-T10 dermatome level arising from spinal cord injury.
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Affiliation(s)
- Jin Kyung Kim
- Department of Neurosurgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
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207
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Jeon Y, Huh BK. Spinal Cord Stimulation for Chronic Pain. ANNALS OF THE ACADEMY OF MEDICINE, SINGAPORE 2009. [DOI: 10.47102/annals-acadmedsg.v38n11p998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Spinal cord stimulation (SCS) is one of the most effective modalities for management of re- fractory neuropathic pain unresponsive to conservative therapies. The SCS has been successful in providing analgesia, improving function, and enhancing quality of life for patients suffering from chronic pain conditions such as failed back surgery syndrome, complex regional pain syndrome, ischaemic and phantom limb pain, and coronary artery disease. This technique has proven to be cost effective in the long term despite its high initial cost. In this review article, we discuss the history of SCS development, mechanism of action, and indications for SCS.
Key words: Failed back surgery syndrome, Ischaemic pain, Neuropathic pain
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Affiliation(s)
- Younghoon Jeon
- Kyungpook National University Hospital, Republic of Korea
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208
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Modulation of neuronal activity in dorsal column nuclei by upper cervical spinal cord stimulation in rats. Neuroscience 2009; 164:770-6. [PMID: 19665525 DOI: 10.1016/j.neuroscience.2009.08.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2009] [Revised: 07/27/2009] [Accepted: 08/02/2009] [Indexed: 11/24/2022]
Abstract
Clinical human and animal studies show that upper cervical spinal cord stimulation (cSCS) has beneficial effects in treatment of some cerebral disorders, including those due to deficient cerebral circulation. However, the underlying mechanisms and neural pathways activated by cSCS using clinical parameters remain unclear. We have shown that a cSCS-induced increase in cerebral blood flow is mediated via rostral spinal dorsal column fibers implying that the dorsal column nuclei (DCN) are involved. The aim of this study was to examine how cSCS modulated neuronal activity of DCN. A spring-loaded unipolar ball electrode was placed on the left dorsal column at cervical (C2) spinal cord in pentobarbital anesthetized, ventilated and paralyzed male rats. Stimulation with frequencies of 1, 10, 20, 50 Hz (0.2 ms, 10 s) and an intensity of 90% of motor threshold was applied. Extracellular potentials of single neurons in DCN were recorded and examined for effects of cSCS. In total, 109 neurons in DCN were isolated and tested for effects of cSCS. Out of these, 56 neurons were recorded from the cuneate nucleus and 53 from the gracile nucleus. Mechanical somatic stimuli altered activity of 87/109 (83.2%) examined neurons. Of the neurons receiving somatic input, 62 were classified as low-threshold and 25 as wide dynamic range. The cSCS at 1 Hz changed the activity of 96/109 (88.1%) of the neurons. Neuronal responses to cSCS exhibited multiple patterns of excitation and/or inhibition: excitation (E, n=21), inhibition (I, n=19), E-I (n=37), I-E (n=8) and E-I-E (n=11). Furthermore, cSCS with high-frequency (50 Hz) altered the activity of 92.7% (51/55) of tested neurons, including 30 E, 24 I, and 2 I-E responses to cSCS. These data suggested that cSCS significantly modulates neuronal activity in DCN. These nuclei might serve as a neural relay for cSCS-induced effects on cerebral dysfunction and diseases.
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209
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Nocom G, Ho KY, Perumal M. Interventional Management of Chronic Pain. ANNALS OF THE ACADEMY OF MEDICINE, SINGAPORE 2009. [DOI: 10.47102/annals-acadmedsg.v38n2p150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Chronic non-cancer pain is a common clinical condition affecting a significant part of the population. This article aims to review the interventional options for non-cancer pain. Multiple searches using Medline were carried out and additional searches were made using reference lists of published papers and book chapters. The article discussed procedures ranging from selective nerve root or zygapophyseal (facet) joint block with local anaesthetics to irreversible neurodestruction with radiofrequency energy or neurolytic agents and neuromodulation with spinal cord stimulation. Other techniques include intraspinal delivery of analgesics. There is evidence that these interventional procedures are valuable both diagnostically and therapeutically.
Key words: Intrathecal drug delivery, Neuropathic, Spine
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210
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Spinal Cord Stimulation for Refractory Angina. Neuromodulation 2009. [DOI: 10.1016/b978-0-12-374248-3.00070-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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211
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Abstract
Nearly 6,750,000 people suffer moderate to severe cancer-related pain each year. Unfortunately, 10% to 15% of these patients fail to achieve acceptable pain relief with conventional management. Spinal cord stimulation (SCS) has been used with increased frequency for successful treatment of intractable cancer pain. We present two cases of intractable, refractory-to-conventional treatment cancer pain that were successfully treated with SCS. Case 1 reports a 51-year-old male with burning pain at the left groin site of inguinal metastases, post-surgical and intraoperative radiation therapy for treatment of squamous cell carcinoma of the anus. Case 2 reports a 43-year-old woman with intractable, burning, throbbing, and shooting pain, post-debulking followed by radiation of a metastatic colon carcinoma. In both cases SCS implantation provided 90% to 100% pain relief, improved functioning and sleep, and discontinuation of pain medications, sustained through 12 months.
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Affiliation(s)
- Alexander E Yakovlev
- Urgent Care, Marshfield Clinic, 1000 North Oak Avenue, Marshfield, WI 54449, USA
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212
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Deer TR, Stewart CD. Complications of Spinal Cord Stimulation: Identification, Treatment, and Prevention. PAIN MEDICINE 2008. [DOI: 10.1111/j.1526-4637.2008.00444.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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213
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The Restore Rechargeable, Implantable Neurostimulator: Handling and Clinical Results of a Multicenter Study. Clin J Pain 2008; 24:325-34. [DOI: 10.1097/ajp.0b013e31816216a9] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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214
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Yang X, Farber JP, Wu M, Foreman RD, Qin C. Roles of dorsal column pathway and transient receptor potential vanilloid type 1 in augmentation of cerebral blood flow by upper cervical spinal cord stimulation in rats. Neuroscience 2008; 152:950-8. [PMID: 18321652 PMCID: PMC2396529 DOI: 10.1016/j.neuroscience.2008.01.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2007] [Revised: 01/04/2008] [Accepted: 01/10/2008] [Indexed: 11/20/2022]
Abstract
Clinical and basic studies have indicated that upper cervical spinal cord stimulation (cSCS) significantly increases cerebral blood flow (CBF), but the mechanisms are incompletely understood. This investigation was conducted to differentiate between stimulation of dorsal column fibers and upper cervical spinal cord cell bodies in cSCS-induced increases in CBF and decreases in cerebrovascular resistance (CVR). cSCS (50 Hz, 0.2 ms, 1 min) was applied on the left C1-C2 dorsal column of pentobarbital anesthetized, ventilated and paralyzed male rats. Laser Doppler flowmetry probes were placed bilaterally over the parietal cortex, and arterial pressure was monitored. cSCS at 30%, 60%, and 90% of motor threshold (MT) produced vasodilation bilaterally in cerebral cortices. Subsequently, cSCS was applied at 90% MT, and ipsilateral responses were recorded. Ibotenic acid (0.3 mg/ml, 0.1 ml) placed on dorsal surface of C1-C2 (n=7) to suppress cell body activity, did not affect cSCS-induced %DeltaCBF (42.5+/-8.1% vs. 36.8+/-7.1%, P>0.05) and %DeltaCVR (-19.4+/-4.2% vs. -15.2+/-5.6%, P>0.05). However, bilateral transection of the dorsal column at rostral C1 (n=8) abolished cSCS-induced changes in CBF and CVR. Also, rostral C1 transection (n=7) abolished cSCS-induced changes in CBF and CVR. Resinferatoxin (RTX), an ultrapotent transient receptor potential vanilloid type 1 (TRPV1) agonist, was used to inactivate TRPV1 containing nerve fibers/cell bodies. RTX (2 microg/ml, 0.1 ml) placed on the C1-C2 spinal cord (n=7) did not affect cSCS-induced %DeltaCBF (60.2+/-8.1% vs. 46.3+/-7.7%, P>0.05) and %DeltaCVR (-25.5+/-3.5% vs. -21.4+/-8.9%, P>0.05). However, i.v. RTX (2 microg/kg, n=9) decreased cSCS-induced %DeltaCBF from 65.0+/-9.5% to 27.4+/-7.2% (P<0.05) and %DeltaCVR from -28.0+/-7.6% to -14.8+/-4.2% (P<0.05). These results indicated that cSCS-increases in CBF and decreases in CVR occurred via rostral spinal dorsal column fibers and did not depend upon C1-C2 cell bodies. Also, our results suggested that cerebral but not spinal TRPV1 was involved in cSCS-induced cerebral vasodilation.
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Affiliation(s)
- X Yang
- Department of Pain Management, Xi'an Jiaotong University First Hospital, Xi'an, Shaanxi 710061, PR China.
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215
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Wu M, Linderoth B, Foreman RD. Putative mechanisms behind effects of spinal cord stimulation on vascular diseases: a review of experimental studies. Auton Neurosci 2008; 138:9-23. [PMID: 18083639 PMCID: PMC2291393 DOI: 10.1016/j.autneu.2007.11.001] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2007] [Revised: 10/29/2007] [Accepted: 11/01/2007] [Indexed: 12/16/2022]
Abstract
Spinal cord stimulation (SCS) is a widely used clinical technique to treat ischemic pain in peripheral, cardiac and cerebral vascular diseases. The use of this treatment advanced rapidly during the late 80's and 90's, particularly in Europe. Although the clinical benefits of SCS are clear and the success rate remains high, the mechanisms are not yet completely understood. SCS at lumbar spinal segments (L2-L3) produces vasodilation in the lower limbs and feet which is mediated by antidromic activation of sensory fibers and decreased sympathetic outflow. SCS at thoracic spinal segments (T1-T2) induces several benefits including pain relief, reduction in both frequency and severity of angina attacks, and reduced short-acting nitrate intake. The benefits to the heart are not likely due to an increase, or redistribution of local blood flow, rather, they are associated with SCS-induced myocardial protection and normalization of the intrinsic cardiac nervous system. At somewhat lower cervical levels (C3-C6), SCS induces increased blood flow in the upper extremities. SCS at the upper cervical spinal segments (C1-C2) increased cerebral blood flow, which is associated with a decrease in sympathetic activity, an increase in vasomotor center activity and a release of neurohumoral factors. This review will summarize the basic science studies that have contributed to our understanding about mechanisms through which SCS produces beneficial effects when used in the treatment of vascular diseases. Furthermore, this review will particularly focus on the antidromic mechanisms of SCS-induced vasodilation in the lower limbs and feet.
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Affiliation(s)
- Mingyuan Wu
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73190, United States.
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216
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Survey of the practice of spinal cord stimulators and intrathecal analgesic delivery implants for management of pain in Canada. Pain Res Manag 2008; 12:281-5. [PMID: 18080047 DOI: 10.1155/2007/312582] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND In 2006, the Canadian Neuromodulation Society was formed. The present survey characterizes the practice of spinal cord stimulator (SCS) and intrathecal analgesic delivery pump (IADP) implantation for pain management in different centres across Canada. METHOD A structured questionnaire was designed to examine the funding source, infrastructure and patient screening process in different centres implanting SCSs and IADPs. Centres that performed more than 10 implants per year were surveyed. The survey was centre-based, ie, each centre received one questionnaire regardless of the number of staff involved in neuromodulation practice. RESULTS Fourteen centres were identified and 13 responded. Implantation of SCS and IADP was performed in 12 and 10 centres, respectively. In most centres, failed back surgery syndrome was the most frequent indication for SCS and IADP implantation. For SCS, all centres always performed a trial; the majority used percutaneous electrode (83%) before the SCS implantation. Routine psychological screening was performed in 25% of centres before any SCS trial procedure. For IADP, all centres performed a trial injection or infusion before implantation. Five centres (50%) performed psychological screening in almost all patients. Continuous infusion techniques were the most popular (50%) used for the trial. CONCLUSION The present survey provides a 'snapshot' of the practice of SCS and IADP implantation in Canada. A review of SCS and IADP trials indicated that Canadian practices are mostly, but not always, consistent with those elsewhere.
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217
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Wu M, Komori N, Qin C, Farber JP, Linderoth B, Foreman RD. Extracellular signal-regulated kinase (ERK) and protein kinase B (AKT) pathways involved in spinal cord stimulation (SCS)-induced vasodilation. Brain Res 2008; 1207:73-83. [PMID: 18374907 DOI: 10.1016/j.brainres.2007.12.072] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2007] [Revised: 12/14/2007] [Accepted: 12/30/2007] [Indexed: 10/22/2022]
Abstract
BACKGROUND AND AIMS SCS is used to improve peripheral circulation in selected patients with ischemia of the extremities. However the mechanisms are not fully understood. The present study investigated whether blockade of ERK and AKT activation modulated SCS-induced vasodilation. METHODS A unipolar ball electrode was placed on the left dorsal column at the lumbar 2-3 spinal segments in rats. Cutaneous blood flows from left and right hind foot pads were recorded with laser Doppler flow perfusion monitors. SCS was applied through a ball electrode at 60% or 90% of MT. U0126, an inhibitor of ERK kinase, or LY294002, an inhibitor of PI3K upstream of AKT, was applied to the lumbar 3-5 spinal segments (n=7, each group). RESULTS U0126 (100 nM, 5 microM and 250 microM) significantly attenuated SCS-induced vasodilation at 60% (100 nM: P<0.05; 5 microM and 250 microM: P<0.01, respectively) and 90% of MT (100 nM and 5 microM: P<0.05; 250 microM: P<0.01, respectively). LY294002 at 100 microM also attenuated SCS-induced vasodilation at 60% and 90% of MT (P<0.05). CONCLUSIONS These data suggest that ERK and AKT pathways are involved in SCS-induced vasodilation.
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Affiliation(s)
- Mingyuan Wu
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73190, USA
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218
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Ativanichayaphong T, He JW, Hagains CE, Peng YB, Chiao JC. A combined wireless neural stimulating and recording system for study of pain processing. J Neurosci Methods 2008; 170:25-34. [PMID: 18262282 DOI: 10.1016/j.jneumeth.2007.12.014] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2007] [Revised: 12/11/2007] [Accepted: 12/19/2007] [Indexed: 11/18/2022]
Abstract
Clinical studies have shown that spinal or cortical neurostimulation could significantly improve pain relief. The currently available stimulators, however, are used only to generate specific electrical signals without the knowledge of physiologically responses caused from the stimulation. We thus propose a new system that can adaptively generate the optimized stimulating signals base on the correlated neuron activities. This new method could significantly improve the efficiency of neurostimulation for pain relief. We have developed an integrated wireless recording and stimulating system to transmit the neuronal signals and to activate the stimulator over the wireless link. A wearable prototype has been developed consisting of amplifiers, wireless modules and a microcontroller remotely controlled by a Labview program in a computer to generate desired stimulating pulses. The components were assembled on a board with a size of 2.5 cm x 5 cm to be carried by a rat. To validate our system, lumbar spinal cord dorsal horn neuron activities of anesthetized rats have been recorded in responses to various types of peripheral graded mechanical stimuli. The stimulation at the periaqueductal gray and anterior cingulate cortex with different combinations of electrical parameters showed a comparable inhibition of spinal cord dorsal horns activities in response to the mechanical stimuli. The Labview program was also used to monitor the neuronal activities and automatically activate the stimulator with designated pulses. Our wireless system has provided an opportunity for further study of pain processing with closed-loop stimulation paradigm in a potential new pain relief method.
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219
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Abstract
Spinal cord stimulation has been used in the treatment of many chronic pain disorders since 1967. In this update, the indications for spinal cord stimulation are reviewed with attention to recent publications. A focused review of the literature on abdominal and visceral pain syndromes is also provided. Furthermore, the technology has evolved from the use of monopolar electrodes to complex electrode arrays. Similarly, the power source has changed from a radio frequency-driven system to a rechargeable impulse generator. These topics are covered, along with a short discussion of implant technique. Finally, we include a review of complications of such therapy. SCS as a technology and therapy continues to evolve.
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Affiliation(s)
- Steven Falowski
- grid.265008.90000000121665843Department of Neurosurgery, Jefferson Medical College, 909 Walnut Street, 2nd Floor, 19107 Philadelphia, PA
| | - Amanda Celii
- grid.265008.90000000121665843Department of Neurosurgery, Jefferson Medical College, 909 Walnut Street, 2nd Floor, 19107 Philadelphia, PA
| | - Ashwini Sharan
- grid.265008.90000000121665843Department of Neurosurgery, Jefferson Medical College, 909 Walnut Street, 2nd Floor, 19107 Philadelphia, PA
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220
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Qin C, Farber JP, Linderoth B, Shahid A, Foreman RD. Neuromodulation of thoracic intraspinal visceroreceptive transmission by electrical stimulation of spinal dorsal column and somatic afferents in rats. THE JOURNAL OF PAIN 2008; 9:71-8. [PMID: 17974489 PMCID: PMC2682554 DOI: 10.1016/j.jpain.2007.08.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2007] [Revised: 08/07/2007] [Accepted: 08/21/2007] [Indexed: 11/28/2022]
Abstract
UNLABELLED Clinical studies have shown that neuromodulation therapies, such as spinal cord stimulation (SCS) and transcutaneous electrical nerve stimulation (TENS), reduce symptoms of chronic neuropathic and visceral pain. The neural mechanisms underlying SCS and TENS therapy are poorly understood. The present study was designed to compare the effects of SCS and TENS on spinal neuronal responses to noxious stimuli applied to the heart and esophagus. Direct stimulation of an intercostal nerve (ICNS) was used to simulate the effects of TENS. Extracellular potentials of left thoracic (T3) spinal neurons were recorded in pentobarbital anesthetized, paralyzed, and ventilated male rats. SCS (50 Hz, 0.2 ms, 3-5 minutes) at a clinical relevant intensity (90% of motor threshold) was applied on the C1-C2 or C8-T1 ipsilateral spinal segments. Intercostal nerve stimulation (ICNS) at T3 spinal level was performed using the same parameters as SCS. Intrapericardial injection of bradykinin (IB, 10 microg/mL, 0.2 mL, 1 minute) was used as the noxious cardiac stimulus. Noxious thoracic esophageal distension (ED, 0.4 mL, 20 seconds) was produced by water inflation of a latex balloon. C1-C2 SCS suppressed excitatory responses of 16/22 T3 spinal neurons to IB and 25/30 neurons to ED. C8-T1 SCS suppressed excitatory responses of 10/15 spinal neurons to IB and 17/23 neurons to ED. ICNS suppressed excitatory responses of 9/12 spinal neurons to IB and 17/22 neurons to ED. These data showed that SCS and ICNS modulated excitatory responses of T3 spinal neurons to noxious stimulation of the heart and esophagus. PERSPECTIVE Neuromodulation of noxious cardiac and esophageal inputs onto thoracic spinal neurons by spinal cord and intercostal nerves stimulation observed in the present study may help account for therapeutic effects on thoracic visceral pain by activating the spinal dorsal column or somatic afferents.
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Affiliation(s)
- Chao Qin
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73910, USA.
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221
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Hatzis A, Stranjalis G, Megapanos C, Sdrolias PG, Panourias IG, Sakas DE. The current range of neuromodulatory devices and related technologies. ACTA NEUROCHIRURGICA. SUPPLEMENT 2007; 97:21-9. [PMID: 17691353 DOI: 10.1007/978-3-211-33079-1_3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The pace of technology dictates changes in every aspect of human life. Medical profession is not an exception. The development of sophisticated electronic devices has radically influenced diagnosis and therapy. Today neurosurgical science is revolutionized with numerous implanted and non-implanted devices that modulate and stimulate the nervous system. Physicians, patients and non-technical experts involved in this field need to understand the core mechanisms and the main differences of this technology so that they can use it effectively. It will take years until clinicians reach a "consensus" about the use of these devices, but in the course of action objective information about the current status of the methods and equipment, and the technical, biological, and financial complications that arise in practice will speed up their public approval and acceptance.
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Affiliation(s)
- A Hatzis
- P. S. Kokkalis Hellenic Center for Neurosurgical Research, Athens, Greece
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222
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De Andrés J, Tatay J, Revert A, Valía JC, Villanueva V. The beneficial effect of spinal cord stimulation in a patient with severe cerebral ischemia and upper extremity ischemic pain. Pain Pract 2007; 7:135-42. [PMID: 17559483 DOI: 10.1111/j.1533-2500.2007.00121.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Spinal cord stimulation (SCS) is used in the treatment of chronic pain, ischemia because of obstructive arterial disease, and anginal pain. Recently, a number of studies have described the effects of the high cervical SCS, including increased cerebral blood flow, although the underlying mechanisms are unknown. This case report describes a patient with a severe complex ischemic condition affecting both cerebral and upper limb blood flow with an associated complex regional pain syndrome in upper limb. While all previous clinical treatments proved ineffective, cervical SCS afforded satisfactory results. Possible mechanisms underlying the cervical SCS effect are discussed.
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Affiliation(s)
- Jose De Andrés
- Valencia University Medical School, and Multidisciplinary Pain Management Department, General University Hospital, Valencia, Spain.
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223
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Paicius RM, Bernstein CA, Lempert-Cohen C. Peripheral Nerve Field Stimulation for the Treatment of Chronic Low Back Pain: Preliminary Results of Long-Term Follow-up: A Case Series. Neuromodulation 2007; 10:279-90. [DOI: 10.1111/j.1525-1403.2007.00116.x] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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224
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Kumar K, Wilson JR. Factors affecting spinal cord stimulation outcome in chronic benign pain with suggestions to improve success rate. ACTA NEUROCHIRURGICA. SUPPLEMENT 2007; 97:91-9. [PMID: 17691362 DOI: 10.1007/978-3-211-33079-1_12] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
For patient selection, psychological factors like fear avoidance, depression, secondary gain or refusal to be weaned off narcotics should be avoided. Trial Stimulation is an important tool to reduce the rate of failed permanent implants, and to improve cost-effectiveness. The etiology of pain has a strong influence on the success rate. The success rate is inversely proportional to the time interval from the initial onset of symptoms to the time of implantation. Multi-polar and multi-channel systems improve the long-term reliability and success rate and have proven to reduce the incidence of open surgery in case of electrode displacement. Third party coverage like the Worker's Compensation negatively affects the long term success. Reducing the complication rate directly benefits long term success rates. The electrode fracture rate can be reduced by using the paramedian approach, the use of three wing silicone anchor placed immediately at the point of exit of the lead from the deep fascia and avoiding a hard plastic twist lock anchor. The displacements can be reduced by fixing the anchor to the deep fascia firmly, supplemented by the use of silicone glue, and by placing the implantable pulse generator (IPG) in the abdominal wall, instead of the gluteal region. The use of prophylactic antibiotics tends to reduce the infection rate.
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Affiliation(s)
- K Kumar
- Department of Surgery, Section of Neurosurgery, Regina General Hospital, University of Saskatchewan, Regina, Saskatchewan, Canada.
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225
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Wu M, Komori N, Qin C, Farber JP, Linderoth B, Foreman RD. Roles of peripheral terminals of transient receptor potential vanilloid-1 containing sensory fibers in spinal cord stimulation-induced peripheral vasodilation. Brain Res 2007; 1156:80-92. [PMID: 17540346 PMCID: PMC1995562 DOI: 10.1016/j.brainres.2007.04.065] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2007] [Revised: 04/16/2007] [Accepted: 04/19/2007] [Indexed: 11/29/2022]
Abstract
BACKGROUND Spinal cord stimulation (SCS) is used to relieve ischemic pain and improve peripheral blood flow in selected patients with peripheral arterial diseases. Our previous studies show that antidromic activation of transient receptor potential vanilloid-1 (TRPV1) containing sensory fibers importantly contributes to SCS-induced vasodilation. OBJECTIVES To determine whether peripheral terminals of TRPV1 containing sensory fibers produces vasodilation that depends upon the release of calcitonin gene-related peptide (CGRP) and nitric oxide (NO) during SCS. METHODS A unipolar ball electrode was placed on the left dorsal column at lumbar spinal cord segments 2-3 in sodium pentobarbital anesthetized, paralyzed and ventilated rats. Cutaneous blood flow from left and right hindpaws was recorded with laser Doppler flow perfusion monitors. SCS was applied through a ball electrode at 30%, 60%, 90% and 300% of motor threshold. Resiniferatoxin (RTX; 2 microg/ml, 100 microl), an ultra potent analog of capsaicin, was injected locally into the left hindpaw to functionally inactivate TRPV-1 containing sensory terminals. In another set of experiments, CGRP(8-37), an antagonist of the CGRP-1 receptor, was injected at 0.06, 0.12 or 0.6 mg/100 microl into the left hindpaw to block CGRP responses; N-omega-nitro-l-arginine methyl ester (L-NAME), a nonselective nitric-oxide synthase (NOS) inhibitor, was injected at 0.02 or 0.2 mg/100 microl into the left hindpaw to block nitric oxide synthesis; (4S)-N-(4-Amino-5[aminoethyl]aminopentyl)-N'-nitroguanidine, TFA, a neuronal NOS inhibitor, was injected at 0.02 or 0.1 mg/100 microl into the left hindpaw to block neuronal nitric oxide synthesis. RESULTS SCS at all intensities produced vasodilation in the left hindpaw, but not in the right. RTX administration attenuated SCS-induced vasodilation at all intensities in the left hindpaw (P<0.05, n=7) compared with responses before RTX. CGRP(8-37) administration attenuated SCS-induced vasodilation in the left hindpaw in a dose dependent manner (linear regression, P<0.05) compared with responses before CGRP(8-37). In addition, L-NAME at a high dose, but not (4S)-N-(4-Amino-5[aminoethyl]aminopentyl)-N'-nitroguanidine, TFA, decreased SCS-induced vasodilation (P<0.05, n=5). CONCLUSION While TRPV1, CGRP and NO are known to be localized in the same nerve terminals, our data indicate that SCS-induced vasodilation depends on CGRP release, but not NO release. NO, released from endothelial cells, may be associated with vascular smooth muscle relaxation and peripheral blood flow increase in response to SCS.
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Affiliation(s)
- Mingyuan Wu
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73190
| | - Naoka Komori
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73190
| | - Chao Qin
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73190
| | - Jay P. Farber
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73190
| | - Bengt Linderoth
- Department of Clinical neuroscience, Section of Neurosurgery, Karolinska Institute, Stockholm, Sweden
| | - Robert D. Foreman
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73190
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226
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Mearini M, Podetta S, Catenacci E, d'Auria P, Cornali C, Mortini P. Spinal Cord Stimulation for the Treatment of Upper and Lower Extremity Neuropathic Pain due to Lyme Disease. Neuromodulation 2007; 10:142-7. [DOI: 10.1111/j.1525-1403.2007.00102.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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227
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Qin C, Lehew RT, Khan KA, Wienecke GM, Foreman RD. Spinal cord stimulation modulates intraspinal colorectal visceroreceptive transmission in rats. Neurosci Res 2007; 58:58-66. [PMID: 17324482 PMCID: PMC1989111 DOI: 10.1016/j.neures.2007.01.014] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2006] [Revised: 01/12/2007] [Accepted: 01/26/2007] [Indexed: 12/30/2022]
Abstract
Previous studies have shown that spinal cord stimulation (SCS) of upper lumbar segments decreases visceromotor responses to mechanical stimuli in a sensitized rat colon and reduces symptoms of irritable bowel syndrome in patients. SCS applied to the upper cervical spinal dorsal column reduces pain of chronic refractory angina. Further, chemical stimulation of C1-C2 propriospinal neurons in rats modulates the responses of lumbosacral spinal neurons to colorectal distension. The present study was designed to compare the effects of upper cervical and lumbar SCS on activity of lumbosacral neurons receiving noxious colorectal input. Extracellular potentials of L6-S2 spinal neurons were recorded in pentobarbital anesthetized, paralyzed and ventilated male rats. SCS (50 Hz, 0.2 ms) at low intensity (90% of motor threshold) was applied to the dorsal column of upper cervical (C1-C2) or upper lumbar (L2-L3) ipsilateral spinal segments. Colorectal distension (CRD, 20 mmHg, 40 mmHg, 60 mmHg, 20s) was produced by air inflation of a latex balloon. Results showed that SCS applied to L2-L3 and C1-C2 segments significantly reduced the excitatory responses to noxious CRD from 417.6+/-68.0 to 296.3+/-53.6 imp (P<0.05, n=24) and from 336.2+/-64.5 to 225.0+/-73.3 imp (P<0.05, n=18), respectively. Effects of L2-L3 and C1-C2 SCS lasted 10.2+/-1.9 and 8.0+/-0.9 min after offset of CRD. Effects of SCS were observed on spinal neurons with either high or low-threshold excitatory responses to CRD. However, L2-L3 or C1-C2 SCS did not significantly affect inhibitory neuronal responses to CRD. C1-C2 SCS-induced effects were abolished by cutting the C7-C8 dorsal column but not by spinal transection at cervicomedullary junction. These data demonstrated that upper cervical or lumbar SCS modulated responses of lumbosacral spinal neurons to noxious mechanical stimulation of the colon, thereby, proved two loci for a potential therapeutic effect of SCS in patients with irritable bowel syndrome and other colonic disorders.
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Affiliation(s)
- C Qin
- Department of Physiology, University of Oklahoma Health Sciences Center, PO Box 26901, Oklahoma City, OK 73104, United States.
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228
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Henderson JM, Schade CM, Sasaki J, Caraway DL, Oakley JC. Prevention of Mechanical Failures in Implanted Spinal Cord Stimulation Systems. Neuromodulation 2006; 9:183-91. [DOI: 10.1111/j.1525-1403.2006.00059.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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229
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Abstract
Faced with rapidly escalating costs, healthcare policy makers are increasingly turning to research evidence to serve as a basis for their population-based decisions on access and funding of new and existing therapies-health technology assessment. A two-stage approach is often used to arrive at a policy recommendation for a given treatment. First, following a systematic review of literature, the "level of evidence" for the treatment is assessed according to epidemiological principles. Then a grade of policy recommendation is provided based on both the level of evidence and the applicability of the evidence to current clinical practice. To assess the current evidence basis for refractory neuropathic pain, a comprehensive search was undertaken for systematic reviews of pharmacological interventions and interventional procedures (ie, spinal cord stimulation, therapeutic blocks, radiofrequency procedures, and surgery). Of the 33 systematic reviews identified, the majority provided evidence for the use of drugs and spinal cord stimulation in the management of various neuropathic pain indications. Little evidence was found for either radiofrequency procedures or therapeutic blocks. By including randomized controlled trials, a number of these systematic reviews indicate a high grade of evidence. Nevertheless, more pragmatic clinical trials are needed to address the evidence needs of healthcare policy makers. These trials should address a direct comparison of the relative effectiveness of neuropathic pain therapies, particularly in combination with other therapies and at different points in the disease course.
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Affiliation(s)
- Rod S Taylor
- Department of Public Health & Epidemiology, University of Birmingham, Birmingham, UK.
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230
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Abstract
Spinal cord stimulation (SCS) for the treatment of neuropathic pain is supported by good-quality randomized controlled trials, prospective and retrospective case studies, and observational case series that confirm its efficacy and safety. SCS has been successfully used in various refractory neuropathic pain conditions, including failed back surgery syndrome (FBSS), neuropathic back and leg pain, and complex regional pain syndrome (CRPS) types I and II. According to the Harbour and Miller Scale (2001), the evidence for SCS in FBSS has been classified as grade B, while that for CRPS type I has been classified as grade A. Clinical evidence has shown that compared to conventional pain therapy, more than two-thirds of carefully selected patients treated with SCS achieved sustained pain relief of 50% or more, with minimal side effects. Many patients were able to reduce their analgesic consumption. Quality of life improved and the majority of patients were happy with their treatment; in some cases, patients were able to return to work. Trial stimulation, which is relatively inexpensive and completely reversible, provides predictive value for long-term efficacy and increases the cost-effectiveness of permanent implantation. Studies consistently report that over time, SCS is potentially cost saving to the healthcare system. At present, SCS is considered a "last resort" in the treatment of refractory neuropathic pain, yet evidence suggests that early intervention with SCS results in greater efficacy and, in the case of FBSS, should be considered before re-operation.
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231
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Affiliation(s)
- Christopher J Winfree
- Department of Neurological Surgery, Columbia University Medical Center, New York, NY, USA
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232
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Lazorthes Y, Verdié JC, Sol JC. Chapter 60 Spinal cord stimulation for neuropathic pain. HANDBOOK OF CLINICAL NEUROLOGY 2006; 81:887-899. [PMID: 18808882 DOI: 10.1016/s0072-9752(06)80064-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
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233
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Braxton EE, Ehrlich GD, Hall-Stoodley L, Stoodley P, Veeh R, Fux C, Hu FZ, Quigley M, Post JC. Role of biofilms in neurosurgical device-related infections. Neurosurg Rev 2005; 28:249-55. [PMID: 15991051 DOI: 10.1007/s10143-005-0403-8] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2004] [Accepted: 04/17/2005] [Indexed: 11/26/2022]
Abstract
Bacterial biofilms have recently been shown to be important in neurosurgical device-related infections. Because the concept of biofilms is novel to most practitioners, it is important to understand that both traditional pharmaceutical therapies and host defense mechanisms that are aimed at treating or overcoming free-swimming bacteria are largely ineffective against the sessile bacteria in a biofilm. Bacterial biofilms are complex surface-attached structures that are composed of an extruded extracellular matrix in which the individual bacteria are embedded. Superimposed on this physical architecture is a complex system of intercellular signaling, termed quorum sensing. These complex organizational features endow biofilms with numerous microenvironments and a concomitant number of distinct bacterial phenotypes. Each of the bacterial phenotypes within the biofilm displays a unique gene expression pattern tied to nutrient availability and waste transport. Such diversity provides the biofilm as a whole with an enormous survival advantage when compared to the individual component bacterial cells. Thus, it is appropriate to view the biofilm as a multicellular organism, akin to metazoan eukaryotic life. Bacterial biofilms are much hardier than free floating or planktonic bacteria and are primarily responsible for device-related infections. Now that basic research has demonstrated that the vast majority of bacteria exist in biofilms, the paradigm of biofilm-associated chronic infections is spreading to the clinical world. Understanding how these biofilm infections affect patients with neurosurgical devices is a prerequisite to developing strategies for their treatment and prevention.
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Affiliation(s)
- Ernest E Braxton
- Department of Neurosurgery, Allegheny General Hospital, Pittsburgh, PA, USA
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234
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Application of Spinal Cord Stimulation for the Treatment of Abdominal Visceral Pain Syndromes: Case Reports. Neuromodulation 2005; 8:14-27. [DOI: 10.1111/j.1094-7159.2005.05216.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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