Search

BACKGROUND: Treatment response to spinal cord stimulation (SCS) is focused on the magnitude of effects on pain intensity. However, chronic pain is a multidimensional condition that may affect individuals in different ways and as such it seems reductionist to evaluate treatment response based solely on a unidimensional measure such as pain intensity. AIM: The aim of this article is to add to a framework started by IMMPACT for assessing the wider health impact of treatment with SCS for people with chronic pain, a "holistic treatment response". DISCUSSION: Several aspects need consideration in the assessment of a holistic treatment response. SCS device data and how it relates to patient outcomes, is essential to improve the understanding of the different types of SCS, improve patient selection, long-term clinical outcomes, and reproducibility of findings. The outcomes to include in the evaluation of a holistic treatment response need to consider clinical relevance for patients and clinicians. Assessment of theholistic response combines two key concepts of patient assessment: (1) patients level of baseline (pre-treatment) unmet need across a range of health domains; (2) demonstration of patient-relevant improvements in these health domains with treatment. The minimal clinical important difference (MCID) is an established approach to reflect changes after a clinical intervention that are meaningful for the patient and can be used to identify treatment response to each individual domain. A holistic treatment response needs to account for MCIDs in all domains of importance for which the patient presents dysfunctional scores pre-treatment. The number of domains included in a holistic treatment response may vary and should be considered on an individual basis. Physiologic confirmation of therapy delivery and utilisation should be included as part of the evaluation of a holistic treatment response and is essential to advance the field of SCS and increase transparency and reproducibility of the findings.

Background Dorsal root ganglion stimulation (DRGS) is an effective treatment for complex regional pain syndrome (CRPS) and post-surgical neuropathic pain. However, some patients have surgical and anatomical conditions that are contraindications to traditional DRGS technique. A novel transgrade approach to DRGS placement has been described and demonstrated effective for post spine surgery patients. We present three patients, each with a different reason in which DRGS would not be accessible via the traditional anterograde approach, who all had successful DRGS transgrade placement. Materials and methods The case series includes three patients with either CRPS or post-surgical neuropathic pain who had an anatomical or post-surgical condition that historically would have rendered DRGS contraindicated. Two patients had previously failed dorsal column stimulation. All three patients had successful placement with the transgrade approach-entry into the contralateral epidural space at the level of the targeted foramen from a cephalad angle. Each patient gave their verbal and written consent to be included in the case series. Results Following treatment with a transgrade approach, all three patients had significant pain relief and improvement in function without complication. Conclusion Barriers to anterograde foraminal access including previous implantation, previous instrumentation, and epidural adhesions may prevent DRGS placement in certain indicated patients. This can be especially challenging in patients who have failed other neuromodulation options like dorsal column stimulation. Our case series demonstrated that the transgrade technique can be successfully used in these cases to increase access to DRGS.

Objectives Complex regional pain syndrome (CRPS) is a disorder in which pain and discomfort are out of proportion to the amount of tissue damage. While prevalence is 20.57 per 100,000 adults, it has not been studied in the U.S. pediatric population. Conservative treatment options include pharmacologic, behavioral, and psychological treatment. If these fail, invasive therapies such as sympathetic blocks and neuromodulation may be performed. The ACCURATE study demonstrated efficacy of dorsal root ganglion (DRG) stimulation for the treatment of refractory CRPS, but did not include pediatric patients and there are no reported cases of its use in the pediatric population. We review the use of neuromodulation for CRPS in pediatric patients and present a novel case using DRG stimulation in an adolescent patient. Materials and methods A literature search was performed for any studies of neuromodulation as treatment of pediatric CRPS. The literature is reviewed and the case of a 17-year-old female with CRPS treated with DRG stimulation is presented. Results A 15-year-old female developed CRPS type I of the left ankle after a sports injury. She was unable to wear a shoe or venture outside the home due to pain, swelling, and allodynia. Conservative therapies, including medications, physical therapy, and lumbosacral sympathetic plexus blocks, failed. At age 17, she underwent DRG stimulator lead placement targeting the left L4 and L5 nerve roots. Her therapy provided 100% relief of pain within four days of placement and was sustained at 30-month follow-up. Conclusions DRG stimulation has been shown to significantly alter the symptomatology in patients with CRPS. This case suggests that DRG stimulation may be as effective for the treatment of refractory CRPS in pediatric patients as in adults.

Objectives The evolution of neuromodulation devices in order to enter magnetic resonance imaging (MRI) scanners has been one of understanding limitations, engineering modifications, and the development of a consensus within the community in which the FDA could safely administer labeling for the devices. In the initial decades of neuromodulation, it has been contraindicated for MRI use with implanted devices. In this review, we take a comprehensive approach to address all the major products currently on the market in order to provide physicians with the ability to determine when an MRI can be performed for each type of device implant. Materials and methods We have prepared a narrative review of MRI guidelines for currently marketed implanted neuromodulation devices including spinal cord stimulators, intrathecal drug delivery systems, peripheral nerve stimulators, deep brain stimulators, vagal nerve stimulators, and sacral nerve stimulators. Data sources included relevant literature identified through searches of PubMed, MEDLINE/OVID, SCOPUS, and manual searches of the bibliographies of known primary and review articles, as well as manufacturer-provided information. Results Guidelines and recommendations for each device and their respective guidelines for use in and around MR environments are presented. Conclusions This is the first comprehensive guideline with regards to various devices in the market and MRI compatibility from the American Society of Pain and Neuroscience.

Introduction: Stereotactic neurosurgical techniques are increasingly used to deliver biologics, such as cells and viruses, although standardized procedures are necessary to ensure consistency and reproducibility. Objective: We provide an instructional guide to help plan for complex image-guided trajectories; this may be of particular benefit to surgeons new to biologic trials and companies planning such trials. Methods: We show how nuclei can be segmented and multiple trajectories with multiple injection points can be created through a single or multiple burr hole(s) based on preoperative images. Screenshots similar to those shown in this article can be used for planning purposes and for quality control in clinical trials. Results: This method enables the precise definition of 3-D target structures, such as the putamen, and efficient planning trajectories for biologic injections. The technique is generalizable and largely independent of procedural format, and thus can be integrated with frame-based or frameless platforms to streamline reproducible therapeutic delivery. Conclusions: We describe an easy-to-use and generalizable protocol for intracerebral trajectory planning for stereotactic delivery of biologics. Although we highlight intracerebral stem cell delivery to the putamen using a frame-based stereotactic delivery system, similar strategies may be employed for different brain nuclei using different platforms. We anticipate this will inform future advanced and fully automated neurosurgical procedures to help unify the field and decrease inherent variability seen with manual trajectory planning.

ObjectiveFor many medical professionals dealing with patients with persistent pain following spine surgery, the term Failed back surgery syndrome (FBSS) as a diagnostic label is inadequate, misleading, and potentially troublesome. It misrepresents causation. Alternative terms have been suggested, but none has replaced FBSS. The International Association for the Study of Pain (IASP) published a revised classification of chronic pain, as part of the new International Classification of Diseases (ICD-11), which has been accepted by the World Health Organization (WHO). This includes the term Chronic pain after spinal surgery (CPSS), which is suggested as a replacement for FBSS.MethodsThis article provides arguments and rationale for a replacement definition. In order to propose a broadly applicable yet more precise and clinically informative term, an international group of experts was established.Results14 candidate replacement terms were considered and ranked. The application of agreed criteria reduced this to a shortlist of four. A preferred option—Persistent spinal pain syndrome—was selected by a structured workshop and Delphi process. We provide rationale for using Persistent spinal pain syndrome and a schema for its incorporation into ICD-11. We propose the adoption of this term would strengthen the new ICD-11 classification.ConclusionsThis project is important to those in the fields of pain management, spine surgery, and neuromodulation, as well as patients labeled with FBSS. Through a shift in perspective, it could facilitate the application of the new ICD-11 classification and allow clearer discussion among medical professionals, industry, funding organizations, academia, and the legal profession.

ObjectiveRefractory psychiatric disease is a major cause of morbidity and mortality worldwide, and there is a great need for new treatments. In the last decade, investigators piloted novel deep brain stimulation (DBS)-based therapies for depression and obsessive–compulsive disorder (OCD). Results from recent pivotal trials of these therapies, however, did not demonstrate the degree of efficacy expected from previous smaller trials. To discuss next steps, neurosurgeons, neurologists, psychiatrists and representatives from industry convened a workshop sponsored by the American Society for Stereotactic and Functional Neurosurgery in Chicago, Illinois, in June of 2016.DesignHere we summarise the proceedings of the workshop. Participants discussed a number of issues of importance to the community. First, we discussed how to interpret results from the recent pivotal trials of DBS for OCD and depression. We then reviewed what can be learnt from lesions and closed-loop neurostimulation. Subsequently, representatives from the National Institutes of Health, the Food and Drug Administration and industry discussed their views on neuromodulation for psychiatric disorders. In particular, these third parties discussed their criteria for moving forward with new trials. Finally, we discussed the best way of confirming safety and efficacy of these therapies, including registries and clinical trial design. We close by discussing next steps in the journey to new neuromodulatory therapies for these devastating illnesses.ConclusionInterest and motivation remain strong for deep brain stimulation for psychiatric disease. Progress will require coordinated efforts by all stakeholders.

INTRODUCTION: The Neuromodulation Appropriateness Consensus Committee (NACC) is dedicated to improving the safety and efficacy of neuromodulation and thus improving the lives of patients undergoing neuromodulation therapies. With continued innovations in neuromodulation comes the need for evolving reviews of best practices. Dorsal root ganglion (DRG) stimulation has significantly improved the treatment of complex regional pain syndrome (CRPS), among other conditions. Through funding and organizational leadership by the International Neuromodulation Society (INS), the NACC reconvened to develop the best practices consensus document for the selection, implantation and use of DRG stimulation for the treatment of chronic pain syndromes. METHODS: The NACC performed a comprehensive literature search of articles about DRG published from 1995 through June, 2017. A total of 2538 article abstracts were then reviewed, and selected articles graded for strength of evidence based on scoring criteria established by the US Preventive Services Task Force. Graded evidence was considered along with clinical experience to create the best practices consensus and recommendations. RESULTS: The NACC achieved consensus based on peer-reviewed literature and experience to create consensus points to improve patient selection, guide surgical methods, improve post-operative care, and make recommendations for management of patients treated with DRG stimulation. CONCLUSION: The NACC recommendations are intended to improve patient care in the use of this evolving therapy for chronic pain. Clinicians who choose to follow these recommendations may improve outcomes.

IMPORTANCE: Many patients with diabetic peripheral neuropathy experience chronic pain and inadequate relief despite best available medical treatments. OBJECTIVE: To determine whether 10-kHz spinal cord stimulation (SCS) improves outcomes for patients with refractory painful diabetic neuropathy (PDN). DESIGN, SETTING, AND PARTICIPANTS: The prospective, multicenter, open-label SENZA-PDN randomized clinical trial compared conventional medical management (CMM) with 10-kHz SCS plus CMM. Participants with PDN for 1 year or more refractory to gabapentinoids and at least 1 other analgesic class, lower limb pain intensity of 5 cm or more on a 10-cm visual analogue scale (VAS), body mass index (calculated as weight in kilograms divided by height in meters squared) of 45 or less, hemoglobin A(1c) (HbA(1c)) of 10% or less, daily morphine equivalents of 120 mg or less, and medically appropriate for the procedure were recruited from clinic patient populations and digital advertising. Participants were enrolled from multiple sites across the US, including academic centers and community pain clinics, between August 2017 and August 2019 with 6-month follow-up and optional crossover at 6 months. Screening 430 patients resulted in 214 who were excluded or declined participation and 216 who were randomized. At 6-month follow-up, 187 patients were evaluated. INTERVENTIONS: Implanted medical device delivering 10-kHz SCS. MAIN OUTCOMES AND MEASURES: The prespecified primary end point was percentage of participants with 50% pain relief or more on VAS without worsening of baseline neurological deficits at 3 months. Secondary end points were tested hierarchically, as prespecified in the analysis plan. Measures included pain VAS, neurological examination, health-related quality of life (EuroQol Five-Dimension questionnaire), and HbA(1c) over 6 months. RESULTS: Of 216 randomized patients, 136 (63.0%) were male, and the mean (SD) age was 60.8 (10.7) years. Additionally, the median (interquartile range) duration of diabetes and peripheral neuropathy were 10.9 (6.3-16.4) years and 5.6 (3.0-10.1) years, respectively. The primary end point assessed in the intention-to-treat population was met by 5 of 94 patients in the CMM group (5%) and 75 of 95 patients in the 10-kHz SCS plus CMM group (79%; difference, 73.6%; 95% CI, 64.2-83.0; P

Background: Various techniques are used across institutions for implantation of deep brain stimulation (DBS) leads. The most used techniques for each step include preoperative MRI fused to in-frame CT, intraoperative fluoroscopy, and postoperative CT, but postimplantation MRI also is used, as it was at our center. We present the quality assurance study performed at our institution after a change from postimplantation MRI performed across the hospital to postimplantation in room CT. Methods: Retrospective chart review of 123 patients who underwent bilateral DBS leads placement without same-day generator placement that was performed. The patients were divided by the type of postoperative imaging that was obtained. Patients were excluded if a unilateral lead placement was performed, if the case was a revision of an existing lead or deviated from the normal protocol. Operative room times and procedure times for each group were analyzed with Wilcoxon rank sums test (WRST) to determine any significant differences between groups. Results: Postoperative MRI was performed for 82 patients, while postoperative CT was performed for 41 patients. A WRST showed a significant reduction in both operative room time (209 min to 170 min, P < 0.0001) and procedure time (140 min to 126 min, P = 0.0019). Conclusion: In-room CT allowed for a significant reduction in operative room time. Lower operative room time has been associated with increased patient comfort, and decreased cost. CT did not alter the revision rate for procedures. The significant reduction in procedure time may be attributed to increased team familiarity with procedure over time.

Background Occipital neuralgia (ON) is a disorder characterized by sharp, electrical, paroxysmal pain, originating from the occiput and extending along the posterior scalp, in the distribution of the greater, lesser, and/or third occipital nerve. Occipital nerve stimulation (ONS) constitutes a promising therapy for medically refractory ON because it is reversible with minimal side effects and has shown continued efficacy with long-term follow-up. Objective To conduct a systematic literature review and provide treatment recommendations for the use of ONS for the treatment of patients with medically refractory ON. Methods A systematic literature search was conducted using the PubMed database and the Cochrane Library to locate articles published between 1966 and April 2014 using MeSH headings and keywords relevant to ONS as a means to treat ON. A second literature search was conducted using the PubMed database and the Cochrane Library to locate articles published between 1966 and June 2014 using MeSH headings and keywords relevant to interventions that predict response to ONS in ON. The strength of evidence of each article that underwent full text review and the resulting strength of recommendation were graded according to the guidelines development methodology of the American Association of Neurological Surgeons/Congress of Neurological Surgeons Joint Guidelines Committee. Results Nine studies met the criteria for inclusion in this guideline. All articles provided Class III Level evidence. Conclusion Based on the data derived from this systematic literature review, the following Level III recommendation can be made: the use of ONS is a treatment option for patients with medically refractory ON.

Peripheral nerve stimulation and peripheral nerve field stimulation involve the delivery of electrical stimulation using implanted electrodes either over a target nerve or over the painful area with the goal of modulating neuropathic pain. The selection of appropriate candidates for this therapy hinges on skillful application of inclusion and exclusion criteria, psychological screening, and an invasive screening trial. Patients with significant improvement in pain severity and pain-related disability during the trial are considered candidates for implantation of a permanent system. As with other implanted devices for neuromodulation, risks of mechanical failures, infection, and neurologic complications exist.

Introduction The International Neuromodulation Society (INS) has identified a need for evaluation and analysis of the practice of neurostimulation of the brain and extracranial nerves of the head to treat chronic pain. Methods The INS board of directors chose an expert panel, the Neuromodulation Appropriateness Consensus Committee (NACC), to evaluate the peer-reviewed literature, current research, and clinical experience and to give guidance for the appropriate use of these methods. The literature searches involved key word searches in PubMed, EMBASE, and Google Scholar dated 1970–2013, which were graded and evaluated by the authors. Results The NACC found that evidence supports extracranial stimulation for facial pain, migraine, and scalp pain but is limited for intracranial neuromodulation. High cervical spinal cord stimulation is an evolving option for facial pain. Intracranial neurostimulation may be an excellent option to treat diseases of the nervous system, such as tremor and Parkinson's disease, and in the future, potentially Alzheimer's disease and traumatic brain injury, but current use of intracranial stimulation for pain should be seen as investigational. Conclusions The NACC concludes that extracranial nerve stimulation should be considered in the algorithmic treatment of migraine and other disorders of the head. We should strive to perfect targets outside the cranium when treating pain, if at all possible.

Background/Aims: A frontal burr hole around the level of the coronal suture is the conventional entry point when performing subthalamic nucleus (STN) deep brain stimulation (DBS). However, alternative approaches may sometimes be necessary. Methods: We present a report of delayed hardware erosion through the scalp in the left frontal region after successful bilateral STN DBS for Parkinson’s disease. The left STN was retargeted via a parietal entry point. Results: Significant improvement in UPDRS motor score (59%) was obtained with bilateral stimulation 6 months after re-operation. The literature was examined for similar approaches and the rationale, risks and benefits of non-frontal entry points in functional neurosurgery were explored. Conclusion: Together with a brief review of STN anatomy, this report demonstrates that the parietal approach to the STN remains a viable option in addition to the more traditional frontal access.

Deep brain stimulation (DBS) is commonly used in the treatment of movement disorders such as Parkinson disease (PD), dystonia, and other tremors.To examine systematic errors in image-guided DBS electrode placement and to explore a calibration strategy for stereotactic targeting.Pre- and postoperative stereotactic MR images were analyzed in 165 patients. The perpendicular error between planned target coordinates and electrode trajectory was calculated geometrically for all 312 DBS electrodes implanted. Improvement in motor unified PD rating scale III subscore was calculated for those patients with PD with at least 6 months of follow-up after bilateral subthalamic DBS.Mean (standard deviation) scalar error of all electrodes was 1.4(0.9) mm with a significant difference between left and right hemispheres. Targeting error was significantly higher for electrodes with coronal approach angle (ARC) ≥10° (P.001). Mean vector error was X: -0.6, Y: -0.7, and Z: -0.4 mm (medial, posterior, and superior directions, respectively). Targeting error was significantly improved by using a systematic calibration strategy based on ARC and target hemisphere (mean: 0.6 mm, P.001) for 47 electrodes implanted in 24 patients. Retrospective theoretical calibration for all 312 electrodes would have reduced the mean (standard deviation) scalar error from 1.4(0.9) mm to 0.9(0.5) mm (36% improvement). With calibration, 97% of all electrodes would be within 2 mm of the intended target as opposed to 81% before calibration. There was no significant correlation between the degree of error and clinical outcome from bilateral subthalamic nucleus DBS (R = 0.07).After calibration of a systematic targeting error an MR image-guided stereotactic approach would be expected to deliver 97% of all electrodes to within 2 mm of the intended target point with a single brain pass.

Stereotactic functional neurosurgical interventions depend on precise anatomic targeting before lesioning or deep brain stimulation (DBS) electrode placement.To examine the degree of subcortical brain shift observed when adopting an image-guided approach to stereotactic functional neurosurgery.Coordinates for the anterior and posterior commissural points (AC and PC) were recorded on thin-slice stereotactic magnetic resonance imaging (MRI) scans performed before and immediately after DBS electrode implantation in 136 procedures. The changes in length of AC-PC and in stereotactic coordinates for AC and PC were calculated for each intervention. In patients with Parkinson disease undergoing bilateral subthalamic nucleus (STN) DBS with at least 6 months of follow-up, pre- and postoperative scores of the motor part of the Unified Parkinson's Disease Rating Scale (UPDRS-III) were reviewed.Mean (SD) change in AC-PC length (DeltaAC-PC) was 0.6 (0.4) mm. There was no statistically significant difference in DeltaAC-PC between groups when examining anatomic target subgroups (P =.95), age subgroups (P = .63), sex (P = .59), and unilateral versus bilateral implantation (P =.15). The mean (SD) vector changes for the commissural points were: -0.1 (0.3) mm in X, -0.4 (0.6) mm in Y, and -0.1 (0.7) mm in Z for the AC; and -0.1 (0.3) mm in X, -0.2 (0.7) mm in Y, and 0.0 (0.7) mm in Z for the PC. There was a negligible correlation between the magnitude of brain shift and percentage improvement in UPDRS-III off-medication in patients undergoing STN DBS for PD (R0.01).Brain shift has long been considered an issue in stereotactic targeting during DBS procedures. However, with the image-guided approach and surgical technique used in this study, subcortical brain shift was extremely limited and did not appear to adversely affect clinical outcome.

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is a commonly employed therapeutic procedure for patients with Parkinson's disease uncontrolled by medical therapies. This series describes the outcomes of 79 consecutive patients that underwent bilateral STN DBS at the National Hospital for Neurology and Neurosurgery between November 2002 and November 2008 using an MRI-guided surgical technique without microelectrode recording. Patients underwent immediate postoperative stereotactic MR imaging. The mean (SD) error in electrode placement was 1.3 (0.6)emsp14;mm. There were no haemorrhagic complications. At a median follow-up period of 12emsp14;months, there was a mean improvement in the off-medication motor part of the Unified Parkinson's Disease Rating Scale (UPDRS III) of 27.7 points (SD 13.8) equivalent to a mean improvement of 52% (p0.0001). In addition, there were significant improvements in dyskinesia duration, disability and pain, with a mean reduction in on-medication dyskinesia severity (sum of dyskinesia duration, disability and pain from UPDRS IV) from 3.15 (SD 2.33) pre-operatively, to 1.56 (SD 1.92) post-operatively (p=0.0001). Quality of life improved by a mean of 5.5 points (median 7.9 points, SD 17.3) on the Parkinson's disease Questionnaire 39 summary index. This series confirms that image-guided STN DBS without microelectrode recording can lead to substantial improvements in motor disability of well-selected PD patients with accompanying improvements in quality of life and most importantly, with very low morbidity.

International audience; Objective: Subthalamic nucleus deep brain stimulation (STN-DBS) is an effective treatment for advanced Parkinson disease (PD). Following STN-DBS, speech intelligibility can deteriorate, limiting its beneficial effect. Here we prospectively examined the short- and long-term speech response to STN-DBS in a consecutive series of patients to identify clinical and surgical factors associated with speech change. Methods: Thirty-two consecutive patients were assessed before surgery, then 1 month, 6 months, and 1 year after STN-DBS in 4 conditions on- and off-medication with on- and off stimulation using established and validated speech and movement scales. Fifteen of these patients were followed up for 3 years. A control group of 12 patients with PD were followed up for 1 year. Results: Within the surgical group, speech intelligibility significantly deteriorated by an average of 14.2% +/- 20.15% off-medication and 16.9% +/- 21.8% on-medication 1 year after STN-DBS. The medical group deteriorated by 3.6% +/- 5.5% and 4.5% +/- 8.8%, respectively. Seven patients showed speech amelioration after surgery. Loudness increased significantly in all tasks with stimulation. A less severe preoperative on-medication motor score was associated with a more favorable speech response to STN-DBS after 1 year. Medially located electrodes on the left STN were associated with a significantly higher risk of speech deterioration than electrodes within the nucleus. There was a strong relationship between high voltage in the left electrode and poor speech outcome at 1 year. Conclusion: The effect of STN-DBS on speech is variable and multifactorial, with most patients exhibiting decline of speech intelligibility. Both medical and surgical issues contribute to deterioration of speech in STN-DBS patients. Classification of evidence: This study provides Class III evidence that STN-DBS for PD results in deterioration in speech intelligibility in all combinations of medication and stimulation states at 1 month, 6 months, and 1 year compared to baseline and to control subjects treated with best medical therapy.