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Objectives:   Spinal cord stimulation (SCS) has become a mainstay in the continuum of care for patients suffering from chronic neuropathic pain of the trunk and limbs. Options for placing these devices have included a percutaneous method of using an epidural needle to place a cylindrical (percutaneous) lead to stimulate the spinal cord, or an open laminotomy method for placing a paddle lead at the location of the surgical decompression of the laminae. Both of these methods have been successful in a high percentage of patients, but neither have been ideal. Limitations of the percutaneous leads have been inefficiency of power delivery, inability to achieve desired depth of stimulation in the spinal cord, occasional lead migration and difficulty covering complex pain patterns. Limitations of the paddle lead have been the need for surgical laminotomy, inability to steer the lead once placed, limits on placement in the vicinity of the surgical decompression, and a perceived risk of increased bleeding and trauma to the tissue. These factors have led many minimally invasive spine specialists to seek new options for SCS. This paper presents the initial US experience with a newly approved device to place both paddle leads, and multi-lead arrays into the epidural space via a percutaneous Seldinger-guided approach through a single needle placement. We will both describe the technique and review the outcomes of some of the early cases., Materials and Methods:   After Investigational Review Board clearance, patients consented to data collection in a prospective fashion regarding the use of a new percutaneous epidural introducer (Epiducer, St. Jude Neurological, Minneapolis, MN, USA) to place paddle leads and complex lead arrays. The patients underwent education regarding expectations and risks of the procedure consistent with our normal preoperative period. Patients underwent preoperative anesthesia screening and proper testing as outlined by the Joint Commission on Hospital Accreditation, and were given the opportunity to ask questions concerning the procedure. Once the patient wished to move forward, they were consented using the approved case reporting form and followed during the course of their care. The initial cases were performed in West Virginia with subsequent cases following at the other centers involved in this analysis. The outcomes of this analysis focused on three areas: 1. The technical success in placing the percutaneous sheath. This included the ability to successfully complete: •  epidural access with a 14-gauge Tuohy needle •  ability to place a styleted guidewire •  ability to introduce the introduction system over the wire into the epidural space •  ability to remove the guidewire and introduction tip leaving the 10-gauge sheath intact. 2. The ability to place the desired lead or leads into the epidural space via the percutaneous introduction sheath. 3. The presence of any major adverse event which were defined as: •  nerve injury •  paraplegia •  worsening of baseline pain •  epidural hematoma •  epidural infection •  dural tear •  dural rent •  retained device that could not be removed. This information was carefully recorded for each implant, and summarized in this communication., Results:   During the initial 30 days of the evaluation period, 43 epidural introduction systems were attempted in 38 patients. In patients in whom more than one paddle lead was placed, the system required the reinsertion of the guidewire through the Epiducer, removal of the Epiducer, and rewiring over the guidewire. This is necessary because the diameter of a paddle lead does not allow two or three leads to be placed without rewiring the system. The success of placement was 42/43, with inability to access the epidural space in one patient in whom ligamentum flavum hypertrophy was present on the preoperative imaging study. In all patients, the system was placed at the L1-L2 level, or lower, based on the Food and Drug Administration labeling. The total numbers of leads placed were 75, with both paddle and percutaneous arrays implanted successfully. There were no adverse events during this prospective surveillance evaluation. Ten patients complained of soreness at the entry site and post-procedure stiffness. These complaints were treated with ice, rest, and analgesics and resolved without incident., Conclusion:   This paper describes the initial US cases of the placement of a paddle lead via a minimally invasive percutaneous method, as well as complex cylindrical arrays with a single needle entry to the epidural space. The device functioned successfully and presented a safe option for placing paddle leads and complex arrays., (© 2012 International Neuromodulation Society.)

For both children and adults with neurological, neurodevelopmental, medical, or psychiatric disorders, neuropsychological assessment can be a valuable tool in determining diagnosis, prognosis, and functional abilities as well as informing clinical management. This review summarizes the contributions of neuropsychological assessment to clinical care across diagnostic categories, with the goal of helping clinicians determine its utility for individual patients.

Introduction: Subcutaneous stimulation (peripheral nerve field stimulation) is a novel neuromodulation modality that has increased in its utilization during the last 10 years. It consists of introducing a lead in the subdermal level to stimulate the small nerve fibers in that layer. Unlike other neuromodulation techniques including direct peripheral nerve stimulation, spinal cord stimulation, or deep brain stimulation, the precise target is not identified., Materials and Methods: To date, there is no clear guideline on the appropriate depth or a method to achieve reproducibility of the appropriate depth to place these leads. From clinical experience, we have found that when electrodes are placed in a layer that is too superficial, stimulation is often painful or lacks efficacy. Further, if they are too deep, the patient may not feel adequate paresthesia or get uncomfortable stimulation including, in some circumstances, muscle contractions., Results: In this small series, we demonstrate a novel concept using a radiofrequency stimulation probe to identify the appropriate depth to place the lead. Reproducibility of results will add clarity to the accumulating data and hopefully increase the chances of adequate stimulation coverage and pain relief., (© 2011 International Neuromodulation Society.)

Objective: In this paper we review the literature on failed back surgery syndrome (FBSS) and use principles of Safety, Appropriateness, Fiscal Neutrality, and Effectiveness (SAFE) to determine the appropriate place for spinal cord stimulation (SCS) for the treatment of FBSS., Methods and Results: We analyzed the most recent literature regarding treatments of pain due to FBSS and used the SAFE principles to reprioritize pain treatments, particularly electrical stimulation therapies, for FBSS in a more appropriate, relevant, and up to date continuum of care., Conclusions: Based on this review and analysis of the safety, appropriateness, cost-effectiveness, and efficacy of treatments for the pain of FBSS, relegating SCS to a last resort therapy is no longer justifiable. SCS should be considered before submitting a patient to either long-term systemic opioid therapy or repeat spinal surgery for chronic pain resulting from FBSS., (© 2011 International Neuromodulation Society.)

Objectives:   Spinal cord stimulation (SCS) has been widely noted as a treatment for ischemic pain secondary to peripheral vascular disease, but evidence in the vasculitis disease state is lacking. In this paper we present two cases that exemplify the potential of SCS in this unique population., Material and Methods:   Two case studies involving patients with the conditions noted including initial findings, treatment protocol, and results documented throughout the treatment regimen. A comprehensive review of the critical literature also was performed., Results:   Both patients showed marked improvement with SCS. Pain scores improved dramatically, with a major improvement in disease symptom and quality of life., Conclusions:   Based on literature and our results, SCS is an effective and safe therapy for patients with therapeutically refractory vasculitis., (© 2011 International Neuromodulation Society.)

Peripheral nerve stimulation and, recently, peripheral nerve field stimulation are excellent options for the control of extremity pain in instances where conventional methods have failed and surgical treatment is ruled inappropriate. New techniques, ultrasound guidance, smaller generators, and task-specific neuromodulatory hardware and leads result in increasingly safe, stable and efficacious treatment of pain in the extremities. Peripheral nerve stimulation has shown to be an increasingly viable option for many painful conditions with neuropathic and possibly nociceptive origins. This chapter focuses on the historical use of neuromodulation in the extremities, technical tasks associated with implant, selection of candidates, and potential pitfalls of and solutions for implanting devices around the peripheral nervous system for extremity pain., (Copyright © 2011 S. Karger AG, Basel.)

Neuromodulation practitioners increasingly recognize the potential for peripheral nerve field stimulation (PNfS) to treat pain originating from the trunk. Conditions resulting in truncal pain that may respond to PNfS include cervical and lumbar postlaminectomy syndrome, inguinal neurapraxia, post-herpetic neuralgia, and post-thoracotomy pain. The focus of this chapter is to review the mechanism of action in PNfS, patient selection factors, programming strategies, and technical considerations., (Copyright © 2011 S. Karger AG, Basel.)

Unlabelled: BACKGROUND, OBJECTIVES, AND METHODS: A few recent reports suggested that spinal cord stimulation (SCS) effectively suppresses chronic abdominal pain. However, there is no consensus on patient selection or technical aspects of SCS for such pain. That is why we conducted national survey and collected 76 case reports. There were six incompletely filled reports, so we analyzed 70 cases., Results: There were 43 female and 27 male patients. SCS was trialed in an average of 4.7 days (median of 4 days). In most patients, the leads were positioned for the SCS trial with their tips at the level of the T5 vertebral body (26 patients) or T6 vertebral body (15 patients). Four patients failed SCS trial: their average baseline visual analog scale (VAS) pain score was 7 +/- 2.4 cm and did not improve at the conclusion of the trial (6.5 +/- 1.9 cm; P = 0.759). Pain relief exceeded 50% in 66 of 70 patients reported. Among those, VAS pain score before the trial averaged 7.9 +/- 1.8 cm. During the trial VAS pain scores decreased to 2.45 +/- 1.45 cm (P < 0.001). The opioid use decreased from 128 +/- 159 mg of morphine sulfate equivalents a day to 79 +/- 112 mg (P < 0.017). During permanent implantation most of the physicians used two octrode leads and were positioned midline at T5-6 levels. The average patient follow-up was 84 weeks. VAS pain scores before an implant were 8 +/- 1.9 cm, while after the implant 2.49 +/- 1.9 cm. The opioid use before an implant was 158 +/- 160 mg and at the last office visit after the implant 36 +/- 49 mg., Conclusion: In conclusion, it seems that the SCS for the treatment of the abdominal visceral pain may provide a positive patient long-term experience, significant improvements in pain scores and a decrease in opioid use.

Objectives:   Intrathecal infusion pumps are increasingly used to deliver analgesics for chronic intractable pain. This trial evaluated the accuracy and efficacy of the new Prometra® Programmable Pump System for intrathecal administration of morphine sulfate to treat chronic intractable pain., Methods:   One hundred and ten patients were given continuous intrathecal morphine sulfate and assessed monthly for up to six months. Accuracy was determined as the ratio of delivered to programmed drug volume (DP ratio). Efficacy was assessed using the visual analog and numeric rating scales and the Oswestry Disability Index., Results:   The mean accuracy of the Prometra pump was 97.1%, with a 90% confidence interval of 96.2-98.0%. Decreases in pain and disability were reported at 68.4% of patient visits. No unanticipated adverse events or device complications were reported., Conclusions:   The Prometra pump provides an accurate, effective, and safe system for intrathecal administration of morphine sulfate for treatment of chronic intractable pain., (© 2009 International Neuromodulation Society.)

With the recent technological advances, neurostimulation has provided new hope for millions of patients with debilitating chronic pain conditions that respond poorly to other therapies. Outcome research demonstrated that patients with failed back surgery syndrome and complex regional pain syndromes benefit significantly from neurostimulation in pain reduction, functional capacity, and quality of life. Increasing clinical evidence supports the use of neurostimulation in post-herpetic neuralgia, peripheral neuropathy, occipital neuralgia, and other neuropathic pain conditions. Strong clinical evidences indicate that neurostimulation offers less invasive and more effective therapies for many patients with ischemic pain caused by cardiovascular and peripheral vascular diseases. A growing body of literature supports neurostimulation for visceral pain in general and interstitial cystitis in particular. As a basic principle, patient selection for the appropriate neurostimulation modalities is essential for safe, efficacious, and cost-effective applications of this therapy. Research with more vigorous designs is needed to establish evidence-based applications of neuromodulation therapy in emerging indications of pain management.

Opioid addiction and abuse are growing problems in the United States, particularly in Appalachian areas, which has led to a major social health problem costing millions of dollars in lost wages, medical care and lost productivity. In some patients with chronic moderate to severe pain, opioids are indicated and can be successfully used with proper monitoring. In this report, we present a case where the use of spinal cord stimulation (SCS) led to an elimination of opioids, a return to work, and to productive function. We also review the literature on the use of SCS to reduce opioid use and improve function based on objective criteria.

Currently accepted chronic pain treatment algorithms have positioned therapies according to levels of invasiveness and up-front costs. After reviewing updated literature on efficacy and cost outcomes of care for patients with chronic pain that include interventional implantable technologies, we offer a new model of thinking when formulating algorithms of care that might include more invasive and costly interventions such as spinal cord stimulation, the SAFE principles. These SAFE principles include "safety,""appropriateness,""fiscal neutrality," and "efficacy.", (© 2009 International Neuromodulation Society.)

Background.  Expert panels of physicians and nonphysicians, all expert in intrathecal (IT) therapies, convened in the years 2000 and 2003 to make recommendations for the rational use of IT analgesics, based on the preclinical and clinical literature known up to those times, presentations of the expert panels, discussions on current practice and standards, and the result of surveys of physicians using IT agents. An expert panel of physicians and nonphysicians has convened in 2007 to update information known regarding IT therapies and to update information on new and novel opioid and nonopioid analgesic compounds that might show promise for IT use. Methods.  A review of preclinical and clinical published relevant studies from 2000 to 2006 was undertaken and disseminated to a convened expert panel of physicians and nonphysicians to discuss new and novel analgesic agents for IT use. Results.  The panelists identified several agents that were worthy of future studies for the clinical and rational use of IT agents that are presented in this article. Conclusions.  A list of nonopioid IT analgesics, including gabapentin, adenosine, octreotide, the χ-conopeptide, Xen2174, the conopeptide, neurotensis 1 agonist, CGX-1160, the ω-conotoxin, AM-336, and physostigmine, were identified as worthy of future research by the panelists., (© 2008 International Neuromodulation Society.)

Background.  Expert panel of physicians and nonphysicians, all expert in intrathecal (IT) therapies, convened in the years 2000 and 2003 to make recommendations for the rational use of IT analgesics based on the preclinical and clinical literature known up to those times, presentations of the expert panel, discussions on current practice and standards, and the result of surveys of physicians using IT agents. An expert panel of physicians and convened in 2007 to review previous recommendations and to form recommendations for the rational use of IT agents as they pertain to new scientific and clinical information regarding the etiology, prevention and treatment for IT granuloma. Method.  A review of preclinical and clinical literature from 2000 to 2006 was undertaken and disseminated to an expert panel of physicians. Focused discussions concerning the rational use of IT agents and its relationship to the etiology of, prevention of, and treatment of IT granuloma were held. Results.  This report presents here new knowledge of the etiology of catheter tip granuloma and guidelines for its prevention and treatment., (© 2008 International Neuromodulation Society.)

Background.  Expert panels of physicians and nonphysicians in the field of intrathecal therapies convened in 2000 and 2003 to make recommendations for the rational use of intrathecal analgesics based on the preclinical and clinical literature known up to those times. An expert panel of physicians convened in 2007 to update previous recommendations and to form guidelines for the rational use of intrathecal opioid and nonopioid agents. Methods.  A review of preclinical and clinical published relevant studies from 2000 to 2006 was undertaken and disseminated to a convened expert panel of physicians and nonphysicians. Focused discussions were held on the rational use of intrathecal agents and a survey asking questions regarding intrathecal therapies management was given to the panelists. Results.  The panelists, after review of the literature from 2000 to 2006 and discussion, created an updated algorithm for the rational use of intrathecal opioid and nonopioid agents in patients with nonmalignant and end-of-life pain. Of note is that the panelists felt that ziconotide, based on new and relevant literature and experience, should be updated to a line one intrathecal drug.

In an effort to improve the performance of implantable intrathecal drug delivery systems, a group of physicians experienced in the management of such devices reviewed surgical practices and principles that were associated with low catheter-related complication rates. Clinical study and postmarket data identified physicians whose patients experienced a relatively low rate of catheter-related complications. Six of those physicians (three anesthesiologists and three neurosurgeons) reviewed the number and types of intrathecal drug pumps and catheters they had implanted, with an emphasis on the specific details of successful catheter implantation techniques. The authors pooled their experiences to reach a consensus on implant techniques that are associated with a low rate of postoperative complications.  The authors found that complications were minimized by the use of specific methods for catheter placement that included: a mid-to-upper lumbar dural entry level, a shallow-angle paramedian oblique insertion trajectory, and meticulous catheter anchoring and tunneling techniques. Systemic antibiotic prophylaxis, attention to pump pocket location, and surgical wound closure techniques also were important in reducing the incidence of postoperative device-related complications. Their experience indicates that specific implantation techniques using a variety of catheters and accessories can be expected to reduce the incidence of complications after implantation of intrathecal drug administration systems.

Objectives: In a companion article, we synthesized current clinical and preclinical data to formulate hypotheses about the etiology of drug administration catheter-tip inflammatory masses. In this article, we communicate our recommendations for the detection, treatment, mitigation, and prevention of such masses., Methods: We reviewed published and unpublished case reports and our own experiences to find methods to diagnose and treat catheter-tip inflammatory masses in a manner that minimized adverse neurological sequelae. We also formulated hypotheses about theoretical ways to mitigate, and possibly, prevent the formation of such masses., Results: Human cases have occurred only in patients with chronic pain who received intrathecal opioid drugs, alone or mixed with other drugs, or in patients who received agents that were not labeled for long-term intrathecal use. Most patients had noncancer pain owing to their large representation among the population with implanted pumps. Such patients also had a longer life expectancy and exposure to intrathecal drugs, and they received higher daily doses than patients with cancer pain. Clues to diagnosis included the loss of analgesic drug effects accompanied by new, gradually progressive neurological symptoms and signs. When a mass was diagnosed before it filled the spinal canal or before it caused severe neurological symptoms, open surgery to remove the mass often was not required. Anecdotal reports and the authors' experiences suggest that cessation of drug administration through the affected catheter was followed by shrinkage or disappearance of the mass over a period of 2-5 months., Conclusions: Attentive follow-up and maintenance of an index of suspicion should permit timely diagnosis, minimally invasive treatment, and avoidance of neurological injury from catheter-tip inflammatory masses. Whenever it is feasible, positioning the catheter in the lumbar thecal sac and/or keeping the daily intrathecal opioid dose as low as possible for as long possible may mitigate the seriousness, and perhaps, reduce the incidence of such inflammatory masses.

Purpose: Implantable intrathecal drug delivery systems (IDDSs) have been used to manage refractory cancer pain, but there are no randomized clinical trial (RCT) data comparing them with comprehensive medical management (CMM)., Patients and Methods: We enrolled 202 patients on an RCT of CMM versus IDDS plus CMM. Entry criteria included unrelieved pain (visual analog scale [VAS] pain scores >/= 5 on a 0 to 10 scale). Clinical success was defined as >/= 20% reduction in VAS scores, or equal scores with >/= 20% reduction in toxicity. The main outcome measure was pain control combined with change of toxicity, as measured by the National Cancer Institute Common Toxicity Criteria, 4 weeks after randomization., Results: Sixty of 71 IDDS patients (84.5%) achieved clinical success compared with 51 of 72 CMM patients (70.8%, P =.05). IDDS patients more often achieved >/= 20% reduction in both pain VAS and toxicity (57.7% [41 of 71] v 37.5% [27 of 72], P =.02). The mean CMM VAS score fell from 7.81 to 4.76 (39% reduction); for the IDDS group, the scores fell from 7.57 to 3.67 (52% reduction, P =.055). The mean CMM toxicity scores fell from 6.36 to 5.27 (17% reduction); for the IDDS group, the toxicity scores fell from 7.22 to 3.59 (50% reduction, P =.004). The IDDS group had significant reductions in fatigue and depressed level of consciousness (P <.05). IDDS patients had improved survival, with 53.9% alive at 6 months compared with 37.2% of the CMM group (P =.06)., Conclusion: IDDSs improved clinical success in pain control, reduced pain, significantly relieved common drug toxicities, and improved survival in patients with refractory cancer pain.

Objective: The only agent approved by the U.S. Food and Drug Administration for chronic intrathecal infusion for the treatment of chronic pain is morphine sulfate. In patients who do not experience adequate relief from intrathecal opioids, bupivacaine is frequently added to increase efficacy. The studies reported here were conducted to demonstrate the stability and compatibility of bupivacaine in a commonly used implantable infusion system and the long-term clinical safety of this therapy., Methods: A commercially available bupivacaine solution (7.5 mg/ml) was incubated at 37 degrees C for 12 weeks with intact delivery systems and with the individual materials that comprise the fluid pathway. Intermittent samples were collected and analyzed using liquid chromatography. Materials chronically exposed to bupivacaine were analyzed for mechanical integrity. One hundred eight patients treated with intrathecal bupivacaine (average dose: 10 mg/d, range: 2-25 mg/d) and opioids for an average duration of 86 weeks were monitored clinically (patient interviews and neurologic examinations) approximately every 4 weeks., Results: Bupivacaine concentrations remained greater than 96% of the starting material after chronic exposure to the delivery system materials or the intact pump-catheter systems. and the mechanical integrity of the delivery system and materials remained intact. When combined with intrathecal morphine or hydromorphone, no clinical evidence of drug-induced toxicity or complications was observed in any patient. Supplementing opioid therapy with bupivacaine allowed the pain patient to continue to be effectively managed using an implantable intrathecal delivery system., Conclusions: Bupivacaine is stable and compatible with a commonly used implantable drug infusion system. In this study, chronic supplementation of intrathecal opioids with bupivacaine was a safe method for providing continued management of chronic pain of cancer or noncancer origin.

Intrathecal drug delivery improves pain relief, reduces suffering, and enhances quality of life in the small proportion of patients who do not respond well to oral analgesics, including oral morphine. Although morphine is the "gold standard," and the only drug approved for intrathecal pain therapy in the United States, off-label use of alternative agents appears promising, particularly in patients with neuropathic pain. Careful patient selection and management are significant determinants of successful treatment outcomes. Patient selection criteria for cancer and nonmalignant pain are similar; however, a more comprehensive psychological and social assessment is required for patients with nonmalignant pain. In addition, all patients (those with cancer or nonmalignant pain) must exhibit a positive response to an epidural or intrathecal screening test. A multidisciplinary team approach, involving psychologists, nurses, physical therapists, social workers, and spiritual leaders should be used to manage patients. Current practices for patient selection and management, screening tests, and dosing guidelines for intrathecal drug delivery systems are discussed.

The significance of coronary artery muscle bridging (MB) has been debated since its first angiographic description by Portsmann and colleagues in 1960 (1). The course is usually benign; however, angina, myocardial infarction, sudden death, arrhythmias, and complete heart block have been reported. In this article, we present a case of coronary artery muscle bridging which caused a patient with no angiographic evidence of atherosclerosis to experience Class III angina.