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Spinal cord stimulation is an effective method of treatment for chronic pain. We previously showed that programming using accelerometry was advantageous for paresthesia-based stimulation. However, programming can be labor intensive.Here we focus on standardized programming for both accelerometer-based paresthesia-induced programming (termed "shuffle") and high-dose (HD) subthreshold programming with stimulation delivered over the T9-10 interspace.In this prospective cross-over study, patients received 4 weeks of shuffle programming and 4 weeks of HD programming in a randomized order. In both intervals, contacts overlying T9-10 were programmed. Pain scales with measurements of activity and sleep were collected at the end of each study arm and compared with preoperative baseline scores.Twelve patients were enrolled, with 10 patients completing this study. Compared with baseline, during the HD study period, significant improvements were seen in worst pain of week (P = 0.03) and current pain (P = 0.04) as rated on Numeric Rating Scale scores and walking on the Activity Test (P = 0.012). No difference was seen from baseline compared with shuffle stimulation or in shuffle stimulation compared with HD stimulation.In this pilot study, we demonstrated that HD stimulation at T9-10 is superior to algorithmic programming of paresthesia-based stimulation. These results compared with our previous work with shuffle suggest that paresthesia-based stimulation may necessitate stimulation of additional contact locations and additional programming to optimize. This algorithmic programming of paresthesia-based stimulation continues to warrant exploration.

INTRODUCTION Patients experience variable long-term improvement in chronic back pain despite successful spinal cord stimulation (SCS) trials. Iliopsoas (IP) size has been shown to differ between patients with low back pain and healthy controls. In this study, we examine whether IP muscle cross-sectional area (CSA) is associated with SCS outcomes. MATERIALS AND METHODS We examined patients for whom we had lumbar MRIs 6.3 years prior to SCS and had baseline and one-year outcome data. Percent change from baseline to one year was calculated for Numeric Rating Scale (NRS), Oswestry Disability Index (ODI), Beck Depression Inventory (BDI), Pain Catastrophizing Scale (PCS), and McGill Pain Questionnaire (MPQ). Correlations between IP muscle CSA, ratio of iliopsoas muscle size to the vertebral body area (P/VBA), and the ratio of iliopsoas muscle size to BMI (P/BMI) were examined. Sex differences were considered. RESULTS A total of 73 subjects were included in this study including 30 females and 43 males. Males had significantly larger IP (males 15.70 ± 0.58, females 9.72 ± 0.43; p

OBJECTIVES Little is known about the effects of spinal cord stimulation (SCS) on chronic low back pain (CLBP) patients with no history of previous spine surgery. Using our prospectively collected database, we evaluate improvements in patients with and without previous spine surgery one-year post SCS implantation. MATERIALS AND METHODS Subjects completed outcome metrics pre-operatively and one-year post-implantation including Numeric Rating Scale (NRS), McGill Pain Questionnaire (MPQ), Oswestry Disability Index (ODI), Beck's Depression Inventory (BDI), and Pain Catastrophizing Scale (PCS). RESULTS We enrolled 134 patients; 82 patients had previous spine surgery and 52 patients did not. At one-year post-SCS implantation, patients with previous spine surgery showed improvements in worst pain experienced, least pain experienced, average pain experienced, pain felt currently, MPQ, MPQ sensory, MPQ affective, PCS, PCS helplessness, PCS rumination, PCS magnification, ODI, and BDI scores (p

Background and purpose Quantitative susceptibility mapping (QSM) has been shown to be valuable in direct targeting for subthalamic nucleus (STN) DBS, given its higher quality of contrast between the STN border and adjacent anatomical structures. The objective is to demonstrate the feasibility of using 1.5 T QSM for direct targeting in STN DBS planning. Material and methods Eleven patients underwent MRI acquisitions using a 1.5 T scanner, including multi-echo gradient echo sequences for generating QSM images. 22 STN targets were planned with direct targeting method using QSM images by one stereotactic neurosurgeon and indirect targeting method using standard protocol by a second stereotactic neurosurgeon. The two physicians were blinded to each other's results. Results The mean coordinates for the STN using direct targeting relative to the mid-commissural point (MCP) was 11.41 ± 2.43 mm lateral, 2.48 ± 0.53 mm posterior and 4.45 ± 0.95 mm inferior. The mean coordinates for the STN using indirect targeting was 11.79 ± 2.51 mm lateral, 2.55 ± 0.54 mm posterior, and 4.84 ± 1.03 mm inferior. The mean (±SEM) radial error between the direct and indirect target was 0.67 ± 0.14 mm. In cases where DBS electrodes were implanted, the radial difference between the indirect and actual target (1.19 ± 0.30 mm) was statistically equivalent to the radial difference between the direct and actual target (1.0 ± 0.27 mm). Conclusions Direct targeting of the STN for DBS implantation using 1.5 T QSM was found to be statistically equivalent to standard protocol surgery planning. This may offer a simpler, more intuitive alternative for DBS surgery planning at centers with 1.5 T MRIs.

Objective Generator site pain is a relatively common phenomenon in patients undergoing spinal cord stimulation (SCS) that complicates management and effective pain relief. This pain may be managed conservatively, with repositioning of the battery and, in some cases, with explant. Here we explore our experience with management of generator site pain (“pocket pain”) in a large single-center study. Methods All SCS permanent implants and implantable pulse generator (IPG) placements over 9 years were reviewed. Of 785 cases, we identified 43 patients with pocket pain (5.5%). Demographics and treatments of the pocket pain cohort were analyzed. Results The mean age (± SEM) of the pocket pain cohort was 46.86 ± 1.06, and there were 10/33 males/females. Females were overrepresented in pocket pain cohort (76.7%) when compared with the total SCS cohort (59.0%) (X2 = 5.93, P = 0.015). Diagnosis included failed back surgery syndrome (51.2%), complex regional pain syndrome (23.3%), and chronic neuropathic pain (25.5%). No patients improved with conservative therapy. All patients either went on to revision (n = 23) or explant (n = 20). Time from initial surgery to development of pocket pain was 7.5 months (range: 0.3–88) and from pocket pain to revision surgery was 4.5 months (range: 0.4–26). In addition, significantly more pocket pain patients (65.1%) had workers’ compensation (WC) insurance compared with patients without pocket pain (24.9%) (X2 = 33.3, P Conclusion In our institutional experience, pocket pain was inadequately managed with conservative treatments. Being female and having SCS filed under WC increased risk of pocket pain. Future work will explore the nuances in device placement based on body shape and manual activity responsibilities.

Background Some patients with chronic pain and implanted spinal cord stimulators or intrathecal (IT) pumps fail to obtain significant pain relief. The use of dual modality treatment with both therapies is understudied. This study evaluated comprehensive outcomes in this patient population and reported outcomes primarily using IT ziconotide. Methods We retrospectively analyzed 11 patients with chronic pain treated with both spinal cord stimulation and IT therapy. When a primary treatment failed to achieve significant pain relief, a secondary device was trialed and implanted. Pain severity (measured by a numeric rating scale) was assessed by the change from baseline to after the first and second intervention. In a subset of patients (n = 6), quality-of-life metrics were also assessed. Outcome measures were analyzed closest to the 1-year follow-up date after implantation of the first modality and then at the most recent follow-up after implantation of the second modality. Results Spinal cord stimulation leads were percutaneous (n = 2) or paddles (n = 9) and commonly covered T8-10. IT medication included ziconotide (n = 8), baclofen (n = 1), hydromorphone (n = 1), and morphine/clonidine (n = 1). There was a mean of 19.64 ± 3.17 months between primary and secondary intervention. There was a significant improvement in pain severity from baseline to implantation of the second modality (P = 0.032) at a mean follow-up of 50.18 ± 11.83 months. Conclusions Dual modality therapy is a potential treatment option in patients who have lost efficacy with a single neuromodulation modality. Further study is required to identify potential responders and nonresponders.

BACKGROUND Patients with deep brain stimulation (DBS) implants have limited access to MRI due to safety concerns associated with RF-induced heating. Currently, MRI in these patients is allowed in 1.5T horizontal bore scanners utilizing pulse sequences with reduced power. However, the use of 3T MRI in such patients is increasingly reported based on limited safety assessments. Here we present the results of comprehensive RF heating measurements for two commercially available DBS systems during MRI at 1.5T and 3T. PURPOSE To assess the effect of imaging landmark, DBS lead configuration, and patient's body composition on RF heating of DBS leads during MRI at 1.5T and 3T. STUDY TYPE Phantom and ex vivo study. POPULATION/SUBJECTS/PHANTOM/SPECIMEN/ANIMAL MODEL Gel phantoms and cadaver brain. FIELD STRENGTH/SEQUENCE 1.5T and 3T, T1 -weighted turbo spin echo. ASSESSMENT RF heating was measured at the tips of DBS leads implanted in brain-mimicking gel. Image artifact was assessed in a cadaver brain implanted with an isolated DBS lead. STATISTICAL TESTS Descriptive. RESULTS We observed substantial fluctuation in RF heating, mainly affected by phantom composition and DBS lead configuration, ranging from 0.14°C to 23.73°C at 1.5T, and from 0.10°C to 7.39°C at 3T. The presence of subcutaneous fat substantially altered RF heating at the electrode tips (3.06°C

Objectives Spinal cord stimulation (SCS) is a well-established procedure for chronic neuropathic pain. Research has established patients with personal psychiatric history do not fare as well as their correspondents following SCS surgery. We explored whether a documented psychiatric family history (PFH) correlated with worse outcomes following SCS surgery. Materials and methods We retrospectively reviewed our single-center, prospectively collected database of patients who received permanent SCS implants over the past eight years. Subjects were separated into those with documented PFH and those without. Subjects completed validated scales at preoperative, 6 ± 2 postoperative, and 12 ± 3 months postoperative visits. The percent change in scores from preoperative to postoperative timepoints was compared between subjects with PFH vs. controls. Results SCS subjects reporting a PFH demonstrated significantly worse 6-month outcomes on Pain Catastrophizing Scale-rumination subscale (p = 0.02), numeric rating scale (NRS) scores on "pain at its least" (p = 0.04) and NRS "pain right now" (p = 0.02). This group also endorsed greater disability as measured by the Oswestry Disability Index (ODI) throughout the follow-up period (p = 0.04 at 6 ± 2 months, p = 0.001 at 12 ± 3 months). Conclusions Subjects with PFH may experience less improvement in disability following SCS as compared to subjects without PFH. They may take longer to achieve the same outcomes, including pain relief and decrease in pain rumination. Our findings show that improvements in the PFH cohort are equivalent to that of the no PFH cohort on all measures except ODI at 12-month follow-up. Thus obtaining a detailed PFH prior to performing SCS is important in order to implement pre-operative coping training for PFH patients, rather than exclusion from SCS.

Despite spinal cord stimulation's (SCS) proven efficacy, failure rates are high with no clear understanding of which patients benefit long term. Currently, patient selection for SCS is based on the subjective experience of the implanting physician. OBJECTIVE: To develop machine learning (ML)–based predictive models of long-term SCS response. METHODS: A combined unsupervised (clustering) and supervised (classification) ML technique was applied on a prospectively collected cohort of 151 patients, which included 31 features. Clusters identified using unsupervised K-means clustering were fitted with individualized predictive models of logistic regression, random forest, and XGBoost. RESULTS: Two distinct clusters were found, and patients in the cohorts significantly differed in age, duration of chronic pain, preoperative numeric rating scale, and preoperative pain catastrophizing scale scores. Using the 10 most influential features, logistic regression predictive models with a nested cross-validation demonstrated the highest overall performance with the area under the curve of 0.757 and 0.708 for each respective cluster. CONCLUSION: This combined unsupervised–supervised learning approach yielded high predictive performance, suggesting that advanced ML-derived approaches have potential to be used as a functional clinical tool to improve long-term SCS outcomes. Further studies are needed for optimization and external validation of these models.

BackgroundWith growing numbers of patients receiving deep brain stimulation (DBS), radiologists are encountering these neuromodulation devices at an increasing rate. Current MRI safety guidelines, however, limit MRI access in these patients.PurposeTo describe an MRI (1.5 T and 3 T) experience and safety profile in a large cohort of participants with active DBS systems and characterize the hardware-related artifacts on images from functional MRI.Materials and MethodsIn this prospective study, study participants receiving active DBS underwent 1.5- or 3-T MRI (T1-weighted imaging and gradient-recalled echo [GRE]-echo-planar imaging [EPI]) between June 2017 and October 2018. Short- and long-term adverse events were tracked. The authors quantified DBS hardware-related artifacts on images from GRE-EPI (functional MRI) at the cranial coil wire and electrode contacts. Segmented artifacts were then transformed into standard space to define the brain areas affected by signal loss. Two-sample t tests were used to assess the difference in artifact size between 1.5- and 3-T MRI.ResultsA total of 102 participants (mean age ± standard deviation, 60 years ± 11; 65 men) were evaluated. No MRI-related short- and long-term adverse events or acute changes were observed. DBS artifacts were most prominent near the electrode contacts and over the frontoparietal cortical area where the redundancy of the extension wire is placed subcutaneously. The mean electrode contact artifact diameter was 9.3 mm ± 1.6, and 1.9% ± 0.8 of the brain was obscured by the coil artifact. The coil artifacts were larger at 3 T than at 1.5 T, obscuring 2.1% ± 0.7 and 1.4% ± 0.7 of intracranial volume, respectively (P < .001). The superficial frontoparietal cortex and deep structures neighboring the electrode contacts were most commonly obscured.ConclusionWith a priori local safety testing, patients receiving deep brain stimulation may safely undergo 1.5- and 3-T MRI. Deep brain stimulation hardware-related artifacts only affect a small proportion of the brain.© RSNA, 2019Online supplemental material is available for this article.See also the editorial by Martin in this issue.

BACKGROUND: Chronic pain occurs in 83% of Parkinson disease (PD) patients and deep brain stimulation (DBS) has shown to result in pain relief in a subset of patients, though the mechanism is unclear. OBJECTIVE: To compare functional magnetic resonance imaging (MRI) data in PD patients with chronic pain without DBS, those whose pain was relieved (PR) with DBS and those whose pain was not relieved (PNR) with DBS. METHODS: Functional MRI (fMRI) with blood oxygen level-dependent activation data was obtained in 15 patients in control, PR, and PNR patients. fMRI was obtained in the presence and absence of a mechanical stimuli with DBS ON and DBS OFF. Voxel-wise analysis using pain OFF data was used to determine which regions were altered during pain ON periods. RESULTS: At the time of MRI, pain was scored a 5.4 ± 1.2 out of 10 in the control, 4.25 ± 1.18 in PNR, and 0.8 ± 0.67 in PR cohorts. Group analysis of control and PNR groups showed primary somatosensory (SI) deactivation, whereas PR patients showed thalamic deactivation and SI activation. DBS resulted in more decreased activity in PR than PNR (P

OBJECTIVE The incidence of hemorrhage in patients who undergo deep brain stimulation (DBS) and spinal cord stimulation (SCS) is between 0.5% and 2.5%. Coagulation status is one of the factors that can predispose patients to the development of these complications. As a routine part of preoperative assessment, the authors obtain prothrombin time (PT), partial thromboplastin time (PTT), and platelet count. However, insurers often cover only PT/PTT laboratory tests if the patient is receiving warfarin/heparin. The authors aimed to examine their experience with abnormal coagulation parameters in patients who underwent neuromodulation. METHODS Patients who underwent neuromodulation (SCS, DBS, or intrathecal pump implantation) over a 9-year period and had preoperative laboratory values available were included. The authors determined abnormal values on the basis of a clinical protocol utilized at their practice, which combined the normal ranges of the laboratory tests and clinical relevance. This protocol had cutoff values of 12 seconds and 39 seconds for PT and PTT, respectively, and < 120,000 platelets/μl. The authors identified risk factors for these abnormalities and described interventions. RESULTS Of the 1767 patients who met the inclusion criteria, 136 had abnormal preoperative laboratory values. Five of these 136 patients had values that were misclassified as abnormal because they were within the normal ranges at the outside facility where they were tested. Fifty-one patients had laboratory values outside the ranges of our protocol, but the surgeons reviewed and approved these patients without further intervention. Of the remaining 80 patients, 8 had known coagulopathies and 24 were receiving warfarin/heparin. The remaining 48 patients were receiving other anticoagulant/antiplatelet medications. These included apixaban/rivaroxaban/dabigatran anticoagulants (n = 22; mean ± SD PT 13.7 ± 2.5 seconds) and aspirin/clopidogrel/other antiplatelet medications (n = 26; mean ± SD PT 14.4 ± 5.8 seconds). Eight new coagulopathies were identified and further investigated with hematological analysis. CONCLUSIONS New anticoagulants and antiplatelet medications are not monitored with PT/PTT, but they affect coagulation status and laboratory values. Although platelet function tests aid in a subset of medications, it is more difficult to assess the coagulation status of patients receiving novel anticoagulants. PT/PTT may provide value preoperatively.

Chronic pain (CP) affects roughly 100 million adults in the United States. These subjects present disproportionately to the emergency department (ED). Neuromodulation (NM) has been shown to reduce ED visits longitudinally in subjects.To compare ED utilization rates between subjects with CP with and without NM.Subjects with failed back surgery syndrome, complex regional pain syndrome, or neuropathic pain diagnosis who visited the hospital between January 1, 2019, and December 31, 2019, were included. Subjects were divided into a NM-treated cohort and a non-NM cohort. Demographic information, medications, and pain provider visits were obtained. Pain-related ED visits between 2017 and 2019 were compared.A total of 2516 subjects were identified; 291 (11.6%) previously underwent NM. The non-NM cohort had significantly higher rate of pain-related ED visits compared with the NM cohort (15.1% vs 10.0%, P = .018). Younger age (odds ratio [OR] = 0.888 [0.843-0.935]), shorter distance to the hospital (OR = 0.807 [0.767-0.849]), lower household income (OR = 0.865 [0.831-0.901]), opioid use (OR = 1.375 [1.291-1.465]), nonopioid use (OR = 1.079 [1.033-1.128]), and non-NM therapy (OR = 1.751 [1.283-2.390]) were significant predictors of ED visits. Opioid use was the only significant predictor (OR = 6.124 [1.417-26.473]) associated with ED visits in the NM cohort.Subjects who underwent NM had fewer visits to the ED when compared with similar subjects who received conventional treatment. Opioid use prompted increased ED utilization in both cohorts. We posit that NM leads to improvement in pain outcomes, integration with multidisciplinary pain specialists, and reduction in severity and frequency of acute pain exacerbations, thereby limiting health care resource utilization.

Introduction: Spinal cord stimulation (SCS) is an efficacious chronic pain treatment most commonly used in middle-aged patients. Results from previous studies that investigated SCS′ effects in older patient populations have been equivocal. We examine whether SCS outcomes correlate with age. Methods: We retrospectively examined prospectively collected outcomes from 189 patients who underwent SCS at Albany Medical Center between 2012 and 2020. The patients completed the Numerical Rating Scale (NRS), McGill Pain Questionnaire (MPQ), Oswestry Disability Index (ODI), Beck Depression Inventory (BDI), and Pain Catastrophizing Scale (PCS) preoperatively and 1 year postoperatively. The mean percent change in each outcome was determined and compared via a regression analysis to determine relationships between patient age and each respective outcome metrics. Demographics were compared between patients aged under 65 versus those aged 65 and older via χ2 tests. Results: All subjects demonstrated the expected improvement on NRS, BDI, PCS, and MPQ from baseline to 1-year follow-up, with several demonstrating statistically significant changes: NRS-worst pain (18.66%, p < 0.001), NRS-least pain (26.9%, p < 0.001), NRS-average pain (26.9%, p < 0.01), NRS-current pain (26.4%, p < 0.001), ODI (19.6%, p < 0.001), PCS (29.8%, p < 0.001), and MPQ (29.4%, p < 0.001). There was no significant difference between patients aged under 65 versus those aged 65 and older based on lead type (p = 0.454). Six patients (3.1%) had lead migration, one of whom was 65 or older. Regression analysis revealed improvements in MPQ-sensory and MPQ-affective scores as age increased (p < 0.001, R2 = 0.09; p = 0.046, R2 = 0.05, respectively). Age did not correlate with NRS, ODI, BDI, or PCS. Diagnosis, spinal level of SCS, and lead type were not found to influence any respective outcome measure based on covariate analysis. Conclusion: This study represents the largest study where age was correlated to specific pain, depression, and disability outcomes following SCS. We provide evidence that SCS outcomes are equivalent, or better, in older patients following SCS. Based on these findings, SCS is a viable option for treatment of chronic pain in elderly patient populations.

Pet ownership has been shown to decrease morbidity and mortality in several aspects of health but has not been studied in chronic pain patients. We evaluate whether subjects who underwent spinal cord stimulation (SCS) and own a pet have improved outcomes compared to non-pet owners.After obtaining IRB approval, we re-contacted 38 subjects who underwent SCS surgery with preoperative and 1-year postoperative data on Numerical Rating Scale (NRS), McGill Pain Questionnaire (MPQ), Oswestry Disability Index (ODI), Beck Depression Inventory (BDI), and Pain Catastrophizing scale (PCS). We examined influence of pets and pet ownership-specific behaviors on improvement in SCS outcomes.Patients included 24 males/14 females with a mean age of 59.9 ± 11.5 years. At mean follow-up of 12.2 months (range 10-14), there were improvements in NRS, ODI, BDI, PCS and MPQ. Twenty subjects owned pets and 18 did not; all believed pet ownership could improve health. Pet owners improved more on NRS-right now (p = 0.05) and BDI (p = 0.05), and were more satisfied with SCS (p = 0.04). No significant improvement was seen in ODI, MPQ, or PCS. However, PCS did improve in pet owners who exercised their pet (PCS-total, p 0.01; PCS-helplessness, p 0.01; PCS-rumination, p = 0.05; PCS-magnification, p = 0.02).We provide preliminary evidence that pet ownership is associated with improved pain, depression and SCS satisfaction. Exercising with a pet also appears to be beneficial in limiting pain catastrophizing. Pets show promise as a novel means to improve patient SCS outcomes.

Objectives Meditation has been shown to improve outcomes for chronic pain by increasing patients' awareness of their own bodies. Some patients have an innate ability to leverage their mind-body connection, and this interoceptive awareness may aid them in garnering pain relief. We explored whether spinal cord stimulation (SCS) patients with greater innate awareness had better outcomes. Materials and methods We contacted 30 thoracic SCS patients with baseline and postoperative pain, psychological, and disability outcomes to complete the Multidimensional Assessment of Interoceptive Awareness (MAIA) survey. MAIA distinguishes between beneficial and maladaptive aspects of the perception of body sensations via six positive subscales (noticing, attention regulation, emotional awareness, self-regulation, body listening, and trusting) and two negative subscales (not distracting, not worrying). MAIA subscales and positive/negative groups were correlated with percentage change in Numerical Rating Scale (NRS), Oswestry Disability Index (ODI), Beck's Depression Inventory (BDI), Pain Catastrophizing Scale (PCS), and McGill Pain Questionnaire (MPQ). Results Patients included 14 males/16 females with a mean age of 58. At a mean follow-up of 14.13 months (range 6-26), NRS, ODI, BDI, PCS, and MPQ showed improvements. Positive traits correlated with improvements in pain (MAIA-self regulation with NRS-worst [p = 0.018], NRS-least [p = 0.042], NRS-average [p = 0.006], NRS-current [p = 0.001]; MAIA-body listening with MPQ-total [p = 0.016] and MPQ-sensory [p = 0.026]). Improvement in PCS-total was associated with higher scores in noticing (p = 0.002), attention regulation (p = 0.017), emotional awareness (p = 0.039), and trusting (p = 0.047). PCS-rumination correlated with MAIA-positive total (p = 0.012). In contrast, better attention regulation signified less improvement in ODI (p = 0.043) and MPQ affective (p = 0.026). Conclusions Higher interoceptive awareness in SCS patients correlated with greater improvement following the procedure, particularly with regards to pain relief and pain catastrophizing. These findings suggest that patients with better mind-body connections may achieve greater pain relief following SCS in this patient population, thereby aiding providers in determining who may benefit from this intervention.

Patients with deep brain stimulation (DBS) devices have limited access to magnetic resonance imaging (MRI) due to safety concerns associated with RF heating generated around the implant. The problem of predicting RF heating of conductive leads is complex with a large parameter space and several interplaying factors. Recently however, off-label use of MRI in patients with DBS devices has been reported based on limited safety assessments, raising the concern that potentially dangerous scenarios may have been overlooked. In this work, we present results of a systematic assessment of RF heating of a commercial DBS device during MRI at 1.5T and 3T, taking into account the effect of device configuration, imaging landmark, and patient’s body composition. Ninety-six (96) RF heating measurements were performed using anthropomorphic phantoms implanted with a full DBS system. We evaluated eight clinically relevant device configurations, implanted in phantoms with different material compositions, and imaged at three different landmarks (head, shoulder, and lower chest) in 1.5 T and 3T scanners. We observed a substantial fluctuation in the RF heating depending on phantom’s composition and device configuration. RF heating in the brain-mimicking gel varied from 0.1°C to 12°C during 1.5 T MRI and from

Background Previous studies have shown decreased pain scores with ziconotide as a first-line agent for intrathecal drug therapy (IDT). Subset analysis suggests that patients with neuropathic pain have greater improvement. We prospectively examine the role of first-line ziconotide IDT on the tridimensional pain experience in ziconotide IDT-naive patients with neuropathic pain. Methods We included patients who underwent a successful ziconotide trial and were scheduled for standard-of-care IDT pump placement. Scores were collected at baseline and latest follow-up for the following measures: Short-Form 36 (SF-36), Oswestry Disability Index (ODI), Beck Depression Inventory, and Pain Catastrophizing Scale (PCS). Numeric rating scale (NRS) scores were also collected at each follow-up visit to monitor patients' pain levels and to guide ziconotide dose titration. Responders were identified as patients who had a previously established minimum clinically important difference of a ≥1.2-point reduction in NRS current scores. Results Eleven of 14 patients completed long-term follow-up. There were 7 responders based on NRS minimum clinically important difference. At a mean (±standard error of the mean) follow-up of 10.91 ± 0.70 months, SF-36 emotional well-being (P = 0.04), SF-36 pain (P = 0.02), and ODI (P = 0.03) significantly improved for the entire cohort and in responders (SF-36 emotional well-being, P = 0.01; SF-36 pain, P = 0.04; ODI, P = 0.02). PCS-Rumination (P = 0.02), PCS-Helplessness (P = 0.02), and PCS-Total (P = 0.003) scores improved significantly for responders only. Conclusions We show that ziconotide IDT improves pain as well as emotional components and function. Our study adds prospective evidence to the literature on IDT for neuropathic pain, specifically its role in improving disability, emotional well-being, and catastrophizing.

Objectives Loneliness as a whole has been characterized as a health-related risk factor and is associated with worse outcomes after cardiac procedures. Evidence suggests that chronic pain patients are particularly vulnerable to feeling lonely. We examined the relationship between different aspects of loneliness and one-year postoperative outcomes after spinal cord stimulation (SCS) for chronic pain. Materials and methods We contacted 69 patients with thoracic SCS who had participated in our prospective outcomes database with one-year follow-up to complete the validated, abbreviated UCLA Loneliness Scale (UCLA-3). We examined responses on question 9 of the Oswestry Disability Index (ODI), question 12 of the Beck Depression Inventory (BDI), and UCLA-3 due to their relevance to different aspects of loneliness. We conducted regression analyses to determine the relationship between aspects of loneliness and pain outcomes. Results We identified that loss of interest in people, companionship, and feeling excluded were associated with pain outcomes. Loss of interest in people was associated with improvement in pain (NRS worst p = 0.021, r = 0.32, NRS least p = 0.004, r = 0.4; NRS right now p = 0.016, r = 0.33). Companionship and feeling excluded were also associated with pain. We examined the interface between depression and total loneliness and found that while both were related to each other, depression was not associated with pain outcomes. Conclusions This study demonstrates an association between loss of interest in people, companionship, and feeling excluded and worse postoperative pain outcomes after receiving SCS. It identifies aspects of loneliness as important factors to consider when predicting the outcomes of SCS therapy for chronic pain control.

BACKGROUNDPatients with deep brain stimulation (DBS) implants have limited access to MRI due to safety concerns associated with RF-induced heating. Currently, MRI in these patients is allowed only in 1.5T horizontal scanners and with pulse sequences with reduced power. Nevertheless, off-label use of MRI at 3T is increasingly reported based on limited safety assessments. Here we present results of systematic RF heating measurements for two commercially available DBS systems during MRI at 1.5T and 3T.PURPOSETo assess the effect of imaging landmark, DBS lead configuration, and patient body composition on RF heating of DBS leads during MRI at 1.5 T and 3T.STUDY TYPEPhantom study.POPULATION/SUBJECTS/PHANTOM/SPECIMEN/ANIMAL MODELGel phantoms and cadaver brain.FIELD STRENGTH/SEQUENCE1.5T and 3T, T1-weighted turbo spin echo.ASSESSMENTRF heating was measured at tips of DBS leads implanted in brain-mimicking gel.STATISTICAL TESTSNone.RESULTSWe observed substantial fluctuation in RF heating mainly affected by phantom composition and DBS lead configuration, ranging from 0.14°C to 23.73°C at 1.5 T, and from 0.10°C to 7.39°C at 3T. The presence of subcutaneous fat substantially altered RF heating at electrode tips (−3.06°C < ΔT < 19.05°C). Introducing concentric loops in the extracranial portion of the lead at the surgical burr hole reduced RF heating by up to 89% at 1.5T and up to 98% at 3T compared to worst case heating scenarios.DATA CONCLUSIONDevice configuration and patient body composition significantly altered the RF heating of DBS leads during MRI at 1.5T and 3T. Interestingly, certain lead trajectories consistently reduced RF heating and image artifact over different imaging landmarks, RF frequencies, and phantom compositions. Such trajectories could be implemented in patients with minimal disruption to the surgical workflow.

OBJECTIVEDeep brain stimulation (DBS) of the subthalamic nucleus (STN) is known to reduce motor symptoms of Parkinson’s disease (PD). The effects of DBS on various nonmotor symptoms often differ from patient to patient. The factors that determine whether or not a patient will respond to treatment have not been elucidated. Here, the authors evaluated sex differences in pain relief after DBS for PD.METHODSThe authors prospectively evaluated 20 patients preoperatively and postoperatively after bilateral STN DBS with the validated numeric rating scale (NRS), Revised Oswestry Disability Index for low-back pain (RODI), and King’s Parkinson’s Disease Pain Scale (KPDPS) and assessed the impact of sex as a biological variable.RESULTSThe cohort consisted of 6 female and 14 male patients with a mean duration of 11.8 ± 2.0 months since DBS surgery. Females were significantly older (p = 0.02). Covariate analysis, however, showed no effect of age, stimulation settings, or other confounding variables. KPDPS total scores statistically significantly improved only among males (p < 0.001). Males improved more than females in musculoskeletal and chronic subsets of the KPDPS (p = 0.03 and p = 0.01, respectively). RODI scores significantly improved in males but not in females (p = 0.03 and p = 0.30, respectively). Regarding the NRS score, the improvements seen in both sexes in NRS were not significant.CONCLUSIONSAlthough it is well recognized that pain complaints in PD are different between men and women, this study is unique in that it examines the sex-specific DBS effects on this symptom. Considering sex as a biological variable may have important implications for DBS pain outcome studies moving forward.

Objective Pain is a prevalent and debilitating nonmotor symptom of Parkinson's disease (PD) that is often inadequately managed. Deep brain stimulation (DBS) has been shown to relieve pain in PD but an effective method of identifying which types of PD pain respond to DBS has not been established. We examine the effects of DBS on different types of PD pain using the King's Parkinson's disease pain scale (KPDPS), the only validated scale of PD pain. Methods We prospectively followed 18 PD patients undergoing subthalamic nucleus (STN) or Globus pallidus interna (GPi) DBS. Subjects completed the KPDPS, low back disability index (LBDI), and McGill pain questionnaire (MPQ), preoperatively and at six months postoperatively. Subjects underwent the unified Parkinson's disease rating scale-III (UPDRS-III) with preoperative scores ON medication and postoperative scores ON medication/DBS stimulation. Results Of the 18 patients, a total of 12 subjects had STN DBS and 6 had GPi DBS. As a group, subjects showed improvement in total KPDPS score at six-month postoperative follow-up (p = 0.004). Fluctuation and nocturnal pain were most significantly improved (p = 0.006, 0.01, respectively). Significant improvements were found in fluctuation-related pain domain following GPi DBS. Conclusions In this pilot study, we are the first group to employ KPDPS to monitor pain relief following DBS in PD patients. We demonstrate that fluctuation-related pain and nocturnal pain significantly improve with DBS. Use of the KPDPS in the future will allow better understanding of how STN and GPi DBS treat PD pain over time.

Background Secondary to the complex care, involved specialty providers, and various etiologies, chronic pelvic pain patients do not receive holistic care. Objective To compare our general and neuromodulation cohorts based on referrals, diagnosis, and therapy and describe our neuromodulation patients. Methods A multidisciplinary team was established at our center. The intake coordinator assessed demographics and facilitated care of enrolled patients. Outcomes were compared using minimal clinical important difference of current Numerical Rating Scale (NRS) between patients with neuropathic pain who received neuromodulation and those who did not. The neuromodulation cohort completed outcome metrics at baseline and recent follow-up, including NRS score (best, worst, and current), Oswestry Disability Index (ODI), Beck Depression Inventory, and Pain Catastrophizing Scale. Results Over 7 yr, 233 patients were referred to our consortium and 153 were enrolled. A total of 55 patients had neuropathic pain and 44 of those were managed medically. Eleven underwent neuromodulation. A total of 45.5% patients of the neuromodulation cohort were classified as responders by minimal clinically important difference compared to 26.6% responders in the control cohort at most recent follow-up (median 25 and 33 mo, respectively). Outcome measures revealed improvement in NRS at worst (P = .007) and best (P = .025), ODI (P = .014), and Pain Catastrophizing Scale Rumination (P = .043). Conclusion Eleven percent of patients were offered neuromodulation. There were more responders in the neuromodulation cohort than the conservatively managed neuropathic pain cohort. Neuromodulation patients showed significant improvement at 29 mo in NRS best and worst pain, disability, and rumination. We share our algorithm for patient management.

BACKGROUND Models have been developed for predicting ideal contact and amplitude for subthalamic nucleus (STN) deep brain stimulation (DBS) for Parkinson disease (PD). Pulse-width is generally varied to modulate the size of the energy field produced. Effects of varying frequency in humans have not been systematically evaluated. OBJECTIVE To examine how altered frequencies affect blood oxygen level-dependent activation in PD. METHODS PD subjects with optimized DBS programming underwent functional magnetic resonance imaging (fMRI). Frequency was altered and fMRI scans/Unified Parkinson Disease Rating Scale motor subunit (UPDRS-III) scores were obtained. Analysis using DBS-OFF data was used to determine which regions were activated during DBS-ON. Peak activity utilizing T-values was obtained and compared. RESULTS At clinically optimized settings (n = 14 subjects), thalamic, globus pallidum externa (GPe), and posterior cerebellum activation were present. Activation levels significantly decreased in the thalamus, anterior cerebellum, and the GPe when frequency was decreased (P

Purpose To assess the impact of synchronization errors between the assumed functional MRI paradigm timing and the deep brain stimulation (DBS) on/off cycling using a custom electrocardiogram-based triggering system Methods A detector for measuring and predicting the on/off state of cycling deep brain stimulation was developed and tested in six patients in office visits. Three-electrode electrocardiogram measurements, amplified by a commercial bio-amplifier, were used as input for a custom electronics box (e-box). The e-box transformed the deep brain stimulation waveforms into transistor-transistor logic pulses, recorded their timing, and propagated it in time. The e-box was used to trigger task-based deep brain stimulation functional MRI scans in 5 additional subjects; the impact of timing accuracy on t-test values was investigated in a simulation study using the functional MRI data. Results Following locking to each patient's individual waveform, the e-box was shown to predict stimulation onset with an average absolute error of 112 ± 148 ms, 30 min after disconnecting from the patients. The subsecond accuracy of the e-box in predicting timing onset is more than adequate for our slow varying, 30-/30-s on/off stimulation paradigm. Conversely, the experimental deep brain stimulation onset prediction accuracy in the absence of the e-box, which could be off by as much as 4 to 6 s, could significantly decrease activation strength. Conclusions Using this detector, stimulation can be accurately synchronized to functional MRI acquisitions, without adding any additional hardware in the MRI environment. Magn Reson Med, 2017. © 2017 International Society for Magnetic Resonance in Medicine.

Objective real-world experience with peripheral nerve stimulation (PNS) is limited. Furthermore, the lack of robust outcome metrics, long-term follow-up and data comparing responders and nonresponders limit the refinement of selection criteria to better identify patients likely to benefit from PNS.We retrospectively analyzed 22 patients with craniofacial pain treated with PNS, and responders were classified as having ≥50% postoperative improvement in the numeric rating scale (NRS). In a subset of patients (n = 11), detailed prospective outcomes metrics were obtained preoperatively and postoperatively, including NRS, Beck Depression Index (BDI), Pain Catastrophizing Scale (PCS), and McGill Pain Questionnaire (MPQ).About 59.1% (13 of 22) of subjects were classified as responders at a mean follow-up of 37.5 ± 5.27 months. Diagnoses included migraine (n = 6), occipital neuralgia (n = 9), trigeminal neuropathic pain (TNP; n = 6), and central poststroke pain (n = 1). Within the TNP subgroup, responders were more likely to have undergone two or more trigeminal neuralgia procedures prior to PNS (p 0.05). In the 11 patients with comprehensive preoperative and postoperative outcome data, we noted significant improvement in NRS (p = 0.0005), BDI (p = 0.04), PCS (p = 0.01), as well as components of PCS (helplessness and magnification, p = 0.02) and MPQ (affective, p = 0.02).The present study adds to the PNS literature by providing long-term data and multiple outcome metrics in a subset of patients. We suggest that BDI, PCS, and MPQ may provide more insight into meaningful response over time. Evaluating functional and quality of life outcomes in patients with craniofacial pain may be more informative than assessing benefit solely based on pain intensity and responder rates.

BACKGROUND Deep brain stimulation (DBS) is a well-accepted treatment of Parkinson's disease (PD). Motor phenotypes include tremor-dominant (TD), akinesia-rigidity (AR), and postural instability gait disorder (PIGD). The mechanism of action in how DBS modulates motor symptom relief remains unknown. OBJECTIVE Blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI) was used to determine whether the functional activity varies in response to DBS depending on PD phenotypes. MATERIALS AND METHODS Subjects underwent an fMRI scan with DBS cycling ON and OFF. The effects of DBS cycling on BOLD activation in each phenotype were documented through voxel-wise analysis. For each region of interest, ANOVAs were performed using T-values and covariate analyses were conducted. Further, a correlation analysis was performed comparing stimulation settings to T-values. Lastly, T-values of subjects with motor improvement were compared to those who worsened. RESULTS As a group, BOLD activation with DBS-ON resulted in activation in the motor thalamus (p

Background Newer generation deep brain stimulation (DBS) systems have recently become available in the United States. Data on real-life experience are limited. We present our initial experience incorporating newer generation DBS with Parkinson's disease (PD) and essential tremor (ET) patients. Newer systems allow for smart energy delivery and more intuitive programming and hardware modifications including constant current and directional segmented contacts. Methods We compared six-month outcomes between 42 newer generation and legacy leads implanted in 28 patients. Two cohorts each included 7 PD patients with bilateral subthalamic nucleus (STN) stimulation and 7 ET patients with unilateral ventral intermediate nucleus (VIM) stimulation of the thalamus. All directional leads included 6172 Infinity 8-Channel Directional leads and Infinity internal pulse generators (Abbott Neuromodulation, Plano, TX, USA) and nondirectional leads included lead 3389 with Activa SC for VIM and PC for STN (Medtronic, Minneapolis, MN, USA). Results Six-month outcomes for medication reduction and motor score improvements between new and legacy DBS systems in PD and ET patients were similar. Directionality was employed in 1/3 of patients. Therapeutic window (difference between amplitude when initial symptom relief was obtained and when intolerable side effects appeared with the contact being used) was significantly greater in new DBS systems in both PD (p = 0.005) and ET (p = 0.035) patients. The windows for new and legacy systems were 3.60 V ± 0.42 and 2.00 V ± 0.32 for STN and 3.06 V ± 0.44 and 1.85 V ± 0.28 for VIM, respectively. Discussion The therapeutic window of newer systems, whether or not directionality was used, was significantly greater than that of the legacy system, which suggests increased benefit and programming options. Improvements in hardware and programming interfaces in the newer systems may also contribute to wider therapeutic windows. We expect that as we alter workflow associated with newer technology, more patients will use directionality, and amplitudes will become lower.

Background: Most fMRI studies on pain perception utilized thermal stimuli due to the lack of a non-metallic reliable, reproducible mechanical stimulus. We explored 2 potential MR compatible mechanical devices and validated one that induced changes on fMRI. Purpose: To validate a noxious mechanical stimulus MR compatible device in a healthy cohort and a chronic pain cohort. Further to ensure this device caused changes on fMRI compared to a pressure device. Methods: Two-healthy controls underwent fMRI scans in the presence/absence of mechanical noxious stimuli using different devices. A paradigm for administering the stimuli with the most robust responses on fMRI was developed. Reproducibility of the device was confirmed in 10 chronic pain patients and age/gender-matched healthy controls. Comparisons of patient demographics including age, sex, and numerical rating scale (NRS) scores between the cohorts were performed using a two-sample t-test. Reproducibility was assessed through repeated-measures ANOVA. Results: Both devices, when administered at 15 seconds on, 30 seconds off induced primary somatosensory cortex (SI) activation on fMRI. The device affecting the nail bed induced consistent discomfort and was subsequently validated. Specifically, a mean pressure of 15.7 ± 0.05 psi induced discomfort that remained consistent over repeated trials (p=0.74). Further, in healthy controls, there was a significant correlation between pressure applied and NRS scores in controls(p

OBJECTIVE Spinal cord stimulation (SCS) has been shown to be effective in treating chronic pain in patients with varying etiologies. However, the impact of pharmacological treatment on augmenting response to SCS has not been previously studied. METHODS We enrolled 108 patients who had undergone SCS surgery and documented their pain preoperatively and at 12 months postoperatively using the Numeric Rating Scale (NRS), McGill Pain Questionnaire (MPQ), Beck Depression Inventory (BDI), Oswestry Disability Index (ODI), Pain Catastrophizing Scale (PCS), and Global Impression of Change (GIC). Pain outcomes were compared between patients receiving SCS alone and in addition to duloxetine. RESULTS At 1-year follow-up, patients receiving duloxetine and SCS (n = 41) had better pain relief in the affective component of MPQ (p < 0.05) than those receiving SCS alone (n = 71). Patients on duloxetine with SCS also were significantly more willing to receive SCS again (p < 0.01). This willingness appeared to be duloxetine dose dependent (p < 0.05). Patients receiving pregabalin or gabapentin with SCS did not have significantly more pain relief than patients receiving SCS alone. CONCLUSION This study shows the combination therapy to be an effective strategy to provide more holistic pain relief and further improve the quality of life of SCS patients.

Background The majority of Parkinson's disease patients with deep brain stimulation (DBS) use a monopolar configuration, which presents challenges for EEG and MRI studies. The literature reports algorithms to convert monopolar to bipolar settings. Purpose/hypothesis To assess brain responses of Parkinson's disease patients implanted with DBS during fMRI studies using their clinical and presumed equivalent settings using a published conversion recipe. Study type Prospective. Subjects Thirteen DBS patients. Field strength/sequence 1.5T and 3T, fMRI using gradient echo-planar imaging. Assessment Patients underwent 30/30sec ON/OFF DBS fMRI scans using monopolar and bipolar settings. To convert to a bipolar setting, the negative contact used for the monopolar configuration remained constant and the adjacent dorsal contact was rendered positive, while increasing the voltage by 30%. fMRI activation/deactivation maps and motor Unified Parkinson's Disease Rating Scale (UPDRS-III) scores were compared for patients in both configurations. Statistical tests T-tests were used to compare UPDRS scores and volumes of tissue activated (VTA) diameters in monopolar and bipolar configurations. Results The patterns of fMRI activation in the monopolar and bipolar configurations were generally different. The thalamus, pallidum, and visual cortices exhibited higher activation using the patient's clinical settings than the presumed equivalent settings. VTA diameters were lower (7 mm vs. 6.3 mm, P = 0.047) and UPDRS scores were generally higher in the bipolar (33.2 ± 16) than in the monopolar configuration (28.3 ± 17.4), without reaching statistical significance (P > 0.05). Data conclusion Monopolar and bipolar configurations result in different patterns of brain activation while using a previously published monopolar-bipolar conversion algorithm. Clinical benefits may be achieved with varying patterns of brain responses. Blind conversion from one to the other should be avoided for purposes of understanding the mechanisms of DBS. Level of evidence 1 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018.