Meredith Barad, MD

All Publications

• Psychological Approaches for Migraine Management. Anesthesiology clinics Sturgeon, J. A., Ehde, D. M., Darnall, B. D., Barad, M. J., Clauw, D. J., Jensen, M. P. 2023; 41 (2): 341-355

  Abstract

  Migraine headaches are among the most prevalent and disabling pain conditions worldwide. Best-practice migraine management is multidisciplinary and includes the psychological approaches to address cognitive, behavioral, and affective factors that worsen pain, distress, and disability. The psychological interventions with the strongest research support are relaxation strategies, cognitive-behavioral therapy, and biofeedback, though the quality of clinical trials for all psychological interventions needs continued improvement. The efficacy of psychological interventions may be improved by validating technology-based delivery systems, developing interventions for trauma and life stress, and precision medicine approaches matching treatments to patients based on specific clinical characteristics.

  View details for DOI 10.1016/j.anclin.2023.02.002

  View details for PubMedID 37245946

• Pain Medicine Education in the United States: Success, Threats, and Opportunities. Anesthesiology clinics Aggarwal, A. K., Kohan, L., Moeschler, S., Rathmell, J., Moon, J. S., Barad, M. 2023; 41 (2): 329-339

  Abstract

  The year 2022 marked the 30th anniversary of the first Accreditation Council for Graduate Medical Education (ACGME) accreditation of pain medicine training programs. Before this, the education of pain medicine practitioners was through primarily an apprenticeship model. Since accreditation, pain medicine education has grown under the national leadership of pain medicine physicians and educational experts from the ACGME, exemplified by the release of Pain Milestones 2.0 in 2022. The rapid growth of knowledge in pain medicine, along with its multidisciplinary nature, poses challenges of fragmentation, standardization of curriculum, and adaptation to societal needs. However, these same challenges present opportunities for pain medicine educators to shape the future of the specialty.

  View details for DOI 10.1016/j.anclin.2023.03.004

  View details for PubMedID 37245945

• Pain Medicine Milestones 2.0: A Step into the Future. Pain medicine (Malden, Mass.) Aggarwal, A., Barad, M., Braza, D. W., McKenzie-Brown, A. M., Lee, D., Mayer, R. S., Przkora, R., Kohan, L., Koka, A., Szabova, A. 2023

  Abstract

  OBJECTIVE: To describe the process of revising the Pain Medicine Milestones 1.0 and implementing changes into the Pain Medicine Milestones 2.0 along with implications for pain medicine trainees.BACKGROUND: Competency-based medical education has been implemented in graduate medical education, including pain medicine. Milestones 1.0, introduced by the Accreditation Council for Graduate Medical Education (ACGME), has been used to assess learners in six competencies and respective sub-competencies. Recognizing areas for improvement in Milestones 1.0, the ACGME initiated the process of Milestones 2.0 and a working group was created to execute this task for pain medicine. The working group discussed revisions; consensus was sought when changes were introduced. Final milestones were agreed upon and made available for public comment prior to publication.RESULTS: Redundant sub-competencies were either merged or eliminated, reducing the number of sub-competencies. A maximum of three rows representing skill, knowledge, behavior and attitude were included for each sub-competency. Harmonized Milestones, aligning with other specialties in a predetermined ACGME framework, were adopted and modified to meet the needs of pain medicine. A supplemental guide was developed to assist educators in implementation of Milestones 2.0 and assessment of trainees.CONCLUSIONS: The intent of the Milestones 2.0 was to create an improved tool that is comprehensive, easier to utilize, and of increased value for pain medicine training programs. It is expected that implementation of Milestones 2.0 will streamline pain medicine trainee assessments by educators and prepare trainees for the future practice of pain medicine while serving to be the foundation of an iterative process to match the evolution of the specialty.

  View details for DOI 10.1093/pm/pnad014

  View details for PubMedID 36786406

• The Molecular Basis and Pathophysiology of Trigeminal Neuralgia. International journal of molecular sciences Chen, Q., Yi, D. I., Perez, J. N., Liu, M., Chang, S. D., Barad, M. J., Lim, M., Qian, X. 2022; 23 (7)

  Abstract

  Trigeminal neuralgia (TN) is a complex orofacial pain syndrome characterized by the paroxysmal onset of pain attacks in the trigeminal distribution. The underlying mechanism for this debilitating condition is still not clearly understood. Decades of basic and clinical evidence support the demyelination hypothesis, where demyelination along the trigeminal afferent pathway is a major driver for TN pathogenesis and pathophysiology. Such pathological demyelination can be triggered by physical compression of the trigeminal ganglion or another primary demyelinating disease, such as multiple sclerosis. Further examination of TN patients and animal models has revealed significant molecular changes, channelopathies, and electrophysiological abnormalities in the affected trigeminal nerve. Interestingly, recent electrophysiological recordings and advanced functional neuroimaging data have shed new light on the global structural changes and the altered connectivity in the central pain-related circuits in TN patients. The current article aims to review the latest findings on the pathophysiology of TN and cross-examining them with the current surgical and pharmacologic management for TN patients. Understanding the underlying biology of TN could help scientists and clinicians to identify novel targets and improve treatments for this complex, debilitating disease.

  View details for DOI 10.3390/ijms23073604

  View details for PubMedID 35408959

• Consensus practice guidelines on interventions for cervical spine (facet) joint pain from a multispecialty international working group. Regional anesthesia and pain medicine Hurley, R. W., Adams, M. C., Barad, M., Bhaskar, A., Bhatia, A., Chadwick, A., Deer, T. R., Hah, J., Hooten, W. M., Kissoon, N. R., Lee, D. W., Mccormick, Z., Moon, J. Y., Narouze, S., Provenzano, D. A., Schneider, B. J., van Eerd, M., Van Zundert, J., Wallace, M. S., Wilson, S. M., Zhao, Z., Cohen, S. P. 2021

  Abstract

  BACKGROUND: The past two decades have witnessed a surge in the use of cervical spine joint procedures including joint injections, nerve blocks and radiofrequency ablation to treat chronic neck pain, yet many aspects of the procedures remain controversial.METHODS: In August 2020, the American Society of Regional Anesthesia and Pain Medicine and the American Academy of Pain Medicine approved and charged the Cervical Joint Working Group to develop neck pain guidelines. Eighteen stakeholder societies were identified, and formal request-for-participation and member nomination letters were sent to those organizations. Participating entities selected panel members and an ad hoc steering committee selected preliminary questions, which were then revised by the full committee. Each question was assigned to a module composed of 4-5 members, who worked with the Subcommittee Lead and the Committee Chairs on preliminary versions, which were sent to the full committee after revisions. We used a modified Delphi method whereby the questions were sent to the committee en bloc and comments were returned in a non-blinded fashion to the Chairs, who incorporated the comments and sent out revised versions until consensus was reached. Before commencing, it was agreed that a recommendation would be noted with >50% agreement among committee members, but a consensus recommendation would require ≥75% agreement.RESULTS: Twenty questions were selected, with 100% consensus achieved in committee on 17 topics. Among participating organizations, 14 of 15 that voted approved or supported the guidelines en bloc, with 14 questions being approved with no dissensions or abstentions. Specific questions addressed included the value of clinical presentation and imaging in selecting patients for procedures, whether conservative treatment should be used before injections, whether imaging is necessary for blocks, diagnostic and prognostic value of medial branch blocks and intra-articular joint injections, the effects of sedation and injectate volume on validity, whether facet blocks have therapeutic value, what the ideal cut-off value is for designating a block as positive, how many blocks should be performed before radiofrequency ablation, the orientation of electrodes, whether larger lesions translate into higher success rates, whether stimulation should be used before radiofrequency ablation, how best to mitigate complication risks, if different standards should be applied to clinical practice and trials, and the indications for repeating radiofrequency ablation.CONCLUSIONS: Cervical medial branch radiofrequency ablation may provide benefit to well-selected individuals, with medial branch blocks being more predictive than intra-articular injections. More stringent selection criteria are likely to improve denervation outcomes, but at the expense of false-negatives (ie, lower overall success rate). Clinical trials should be tailored based on objectives, and selection criteria for some may be more stringent than what is ideal in clinical practice.

  View details for DOI 10.1136/rapm-2021-103031

  View details for PubMedID 34764220

• Chronic disabling postpartum headache after unintentional dural puncture during epidural anaesthesia: a prospective cohort study. British journal of anaesthesia Ansari, J. R., Barad, M., Shafer, S., Flood, P. 2021; 127 (4): 600-607

  Abstract

  BACKGROUND: Unintentional dural puncture with an epidural needle complicates approximately 1% of epidural anaesthetics and causes an acute headache in 60-80% of these patients. Several retrospective studies suggest an increased risk of chronic headache. We assessed the relationship between unintentional dural puncture and chronic disabling headache, defined as one or more functionally limiting headaches within a 2-week interval ending 2, 6, and 12 months postpartum.METHODS: In this prospective observational study, parturients who experienced unintentional dural puncture were matched 1:4 with control patients. Patients completed questionnaires regarding characteristics of headache and back pain pre-pregnancy, during pregnancy, immediately postpartum, and at 2, 6, and 12 months postpartum. The primary outcome was prevalence of disabling headache in the past 2 weeks, assessed at 2 months postpartum. Secondary outcomes included prevalence and characteristics of headache and back pain at these time points.RESULTS: We enrolled 99 patients. At 2 and 6 months postpartum, the prevalence of disabling headache was greater among patients with unintentional dural puncture than matched controls (2 months, 74% vs 38%, relative risk 1.9, 95% confidence interval 1.2-2.9, P=0.009; 6 months, 56% vs 25%, relative risk 2.1, 95% confidence interval 1.1-4.0, P=0.033). There was no difference in the prevalence of back pain at any time point.CONCLUSIONS: Our prospective trial confirms retrospective studies that chronic headache is more prevalent among women who experienced unintentional dural puncture compared with controls who received uncomplicated neuraxial anaesthesia. This finding has implications for the. patient consent process and recommendations for long-term follow-up of patients who experience unintentional dural puncture.

  View details for DOI 10.1016/j.bja.2021.05.020

  View details for PubMedID 34548152

• The Pain Medicine Fellowship Telehealth Education Collaborative. Pain medicine (Malden, Mass.) Hascalovici, J., Kohan, L., Spektor, B., Sobey, C., Meroney, M., Anitescu, M., Barad, M., Steinmann, A., Vydyanathan, A., Wahezi, S. 2021

  View details for DOI 10.1093/pm/pnab251

  View details for PubMedID 34402913

• Percutaneous Interventional Strategies for Migraine Prevention: A Systematic Review and Practice Guideline. Pain medicine (Malden, Mass.) Barad, M., Ailani, J., Hakim, S. M., Kissoon, N. R., Schuster, N. M. 2021

  Abstract

  OBJECTIVE: To systematically evaluate the efficacy and effectiveness of percutaneous interventional treatments for prevention of migraine through a qualitative and (when possible) quantitative analysis.METHODS: An expert panel was asked to develop recommendations for the multidisciplinary preventive treatment of migraine, including interventional strategies. The committee conducted a systematic review and (when evidence was sufficient) a meta-analytic review using GRADE criteria and the modified Cochrane risk of bias analysis available in the Covidence data management program. Clinical questions addressed adults with migraine who should be offered prevention. Examined outcomes included headache days, acute medication use, and functional impairment. Acute management of migraine was outside the scope of this guideline.RESULTS: The committee screened 1195 studies and assessed 352 by full text, yielding 16 randomized controlled trials that met inclusion criteria.RECOMMENDATIONS/CONCLUSIONS: As informed by evidence related to the preselected outcomes, adverse event profile, cost, and values and preferences of patients, onabotulinumtoxinA received a strong recommendation for chronic migraine prevention and a weak recommendation against use for episodic migraine prevention. Greater occipital nerve blocks received a weak recommendation for chronic migraine prevention. For greater occipital nerve block, steroid received a weak recommendation against use vs local anesthetic alone. Occipital nerve with supraorbital nerve blocks, sphenopalatine ganglion blocks, cervical spine percutaneous interventions, and implantable stimulation all received weak recommendations for chronic migraine prevention. The committee found insufficient evidence to assess trigger point injections in migraine prevention and highly discouraged use of intrathecal medication.

  View details for DOI 10.1093/pm/pnab236

  View details for PubMedID 34382092

• Characterization of chronic overlapping pain conditions in patients with chronic migraine: A CHOIR study. Headache Barad, M. J., Sturgeon, J. A., Hong, J., Aggarwal, A. K., Mackey, S. C. 2021

  Abstract

  OBJECTIVE: Chronic overlapping pain conditions (COPCs) represent a co-aggregation of widespread pain disorders. We characterized differences in physical and psychosocial functioning in patients with chronic migraine (CM) and those with CM and COPCs.BACKGROUND: Patients with CM and COPCs have been identified as a distinct subgroup of patients with CM, and these patients may be vulnerable to greater symptom severity and burden.METHODS: Data were extracted from Collaborative Health Outcomes Information Registry (an open-source learning health-care system), completed at the patients' first visit at a large tertiary care pain management center and electronic medical records. In 1601 patients with CM, the number of non-cephalic areas of pain endorsed on a body map was used to examine the differences in pain, physical and psychosocial function, adverse life experience, and health-care utilization.RESULTS: Patients endorsing more body map regions reported significantly worse symptoms and function across all domains. Scored on a t-score metric (mean = 50, SD = 10), endorsement of one additional body map region corresponded with a 0.69-point increase in pain interference (95% CI = 0.55, 0.82; p<0.001; Cohen's f=0.328), 1.15-point increase in fatigue (95% CI = 0.97, 1.32; p<0.001; Cohen's f=0.432), and 1.21-point decrease in physical function (95% CI = -1.39, -1.03; p<0.001; Cohen's f=0.560). Patients with more widespread pain reported approximately 5% more physician visits (95% CI = 0.03, 0.07; p<0.001), and patients reporting adverse life events prior to age 17 endorsed 22% more body map regions (95% CI = 0.11, 0.32; p<0.001).CONCLUSIONS: Patients with CM and other overlapping pain conditions as noted on the body map report significantly worse pain-related physical function, psychosocial functioning, increased health-care utilization, and greater association with adverse life experiences, compared with those with localized CM. This study provides further evidence that patients with CM and co-occurring pain conditions are a distinct subgroup of CM and can be easily identified through patient-reported outcome measures.

  View details for DOI 10.1111/head.14129

  View details for PubMedID 34184263

• Did she have an epidural? The long-term consequences of postdural puncture headache and the role of unintended dural puncture. Headache Barad, M., Carroll, I., Reina, M. A., Ansari, J., Flood, P. 2021

  Abstract

  This narrative literature review examines the long-term impact of postdural puncture headache (PDPH) in postpartum women following an unintended dural puncture (UDP) with a large bore needle commonly used for epidural catheter placement. It seeks to bridge the knowledge gap for the neurologist as to the mounting body of obstetric anesthesia literature on the development of chronic headache after PDPH with this unique needle.Headache is the most common complication of dural puncture, and the risk is greatest in the parturient population. Preexisting risk factors for this population include youth and sex, and after UDP with a large bore needle, almost 70%-80% report a headache. Additionally, there appears to be a significant cohort who experience long-term, persistent headache after UDP.We performed a narrative review of literature using PubMed, searching terms that included long-term follow-up after UDP with a large bore needle in the postpartum population.In women who had UDP with a large bore needle used for epidural catheter placement at delivery, the rate of chronic debilitating headache is around 30% in the months following delivery and may persist for up to a year or longer.Based on the existing literature, we have mounting evidence that UDP with the large bore needle used to place an epidural catheter should be understood as a high-risk inciting event for the development of long-term headaches not simply a high risk of acute PDPH. Additionally, consideration should be given to stratifying the etiology of PDPH, based on needle type, and recognizing the entity of chronic PDPH, thus allowing for improvements in research and diagnosis.

  View details for DOI 10.1111/head.14221

  View details for PubMedID 34570902

• Consensus practice guidelines on interventions for cervical spine (facet) joint pain from a multispecialty international working group. Pain medicine (Malden, Mass.) Hurley, R. W., Adams, M. C., Barad, M., Bhaskar, A., Bhatia, A., Chadwick, A., Deer, T. R., Hah, J., Hooten, W. M., Kissoon, N. R., Lee, D. W., Mccormick, Z., Moon, J. Y., Narouze, S., Provenzano, D. A., Schneider, B. J., van Eerd, M., Van Zundert, J., Wallace, M. S., Wilson, S. M., Zhao, Z., Cohen, S. P. 2021

  Abstract

  The past two decades have witnessed a surge in the use of cervical spine joint procedures including joint injections, nerve blocks and radiofrequency ablation to treat chronic neck pain, yet many aspects of the procedures remain controversial.In August 2020, the American Society of Regional Anesthesia and Pain Medicine and the American Academy of Pain Medicine approved and charged the Cervical Joint Working Group to develop neck pain guidelines. Eighteen stakeholder societies were identified, and formal request-for-participation and member nomination letters were sent to those organizations. Participating entities selected panel members and an ad hoc steering committee selected preliminary questions, which were then revised by the full committee. Each question was assigned to a module composed of 4-5 members, who worked with the Subcommittee Lead and the Committee Chairs on preliminary versions, which were sent to the full committee after revisions. We used a modified Delphi method whereby the questions were sent to the committee en bloc and comments were returned in a non-blinded fashion to the Chairs, who incorporated the comments and sent out revised versions until consensus was reached. Before commencing, it was agreed that a recommendation would be noted with >50% agreement among committee members, but a consensus recommendation would require ≥75% agreement.Twenty questions were selected, with 100% consensus achieved in committee on 17 topics. Among participating organizations, 14 of 15 that voted approved or supported the guidelines en bloc, with 14 questions being approved with no dissensions or abstentions. Specific questions addressed included the value of clinical presentation and imaging in selecting patients for procedures, whether conservative treatment should be used before injections, whether imaging is necessary for blocks, diagnostic and prognostic value of medial branch blocks and intra-articular joint injections, the effects of sedation and injectate volume on validity, whether facet blocks have therapeutic value, what the ideal cut-off value is for designating a block as positive, how many blocks should be performed before radiofrequency ablation, the orientation of electrodes, whether larger lesions translate into higher success rates, whether stimulation should be used before radiofrequency ablation, how best to mitigate complication risks, if different standards should be applied to clinical practice and trials, and the indications for repeating radiofrequency ablation.Cervical medial branch radiofrequency ablation may provide benefit to well-selected individuals, with medial branch blocks being more predictive than intra-articular injections. More stringent selection criteria are likely to improve denervation outcomes, but at the expense of false-negatives (ie, lower overall success rate). Clinical trials should be tailored based on objectives, and selection criteria for some may be more stringent than what is ideal in clinical practice.

  View details for DOI 10.1093/pm/pnab281

  View details for PubMedID 34788462

• Development and Internal Validation of a Multivariable Prediction Model for Individual Episodic Migraine Attacks Based on Daily Trigger Exposures. Headache Holsteen, K. K., Hittle, M., Barad, M., Nelson, L. M. 2020

  Abstract

  OBJECTIVE: To develop and internally validate a multivariable predictive model for days with new-onset migraine headaches based on patient self-prediction and exposure to common trigger factors.BACKGROUND: Accurate real-time forecasting of one's daily risk of migraine attack could help episodic migraine patients to target preventive medications for susceptible time periods and help decrease the burden of disease. Little is known about the predictive utility of common migraine trigger factors.METHODS: We recruited adults with episodic migraine through online forums to participate in a 90-day prospective daily-diary cohort study conducted through a custom research application for iPhone. Every evening, participants answered questions about migraine occurrence and potential predictors including stress, sleep, caffeine and alcohol consumption, menstruation, and self-prediction. We developed and estimated multivariable multilevel logistic regression models for the risk of a new-onset migraine day vs a healthy day and internally validated the models using repeated cross-validation.RESULTS: We had 178 participants complete the study and qualify for the primary analysis which included 1870 migraine events. We found that a decrease in caffeine consumption, higher self-predicted probability of headache, a higher level of stress, and times within 2days of the onset of menstruation were positively associated with next-day migraine risk. The multivariable model predicted migraine risk only slightly better than chance (within-person C-statistic: 0.56, 95% CI: 0.54, 0.58).CONCLUSIONS: In this study, episodic migraine attacks were not predictable based on self-prediction or on self-reported exposure to common trigger factors. Improvements in accuracy and breadth of data collection are needed to build clinically useful migraine prediction models.

  View details for DOI 10.1111/head.13960

  View details for PubMedID 33022773

• Response to BotulinumtoxinA in a migraine cohort with multiple comorbidities and widespread pain. Regional anesthesia and pain medicine Barad, M., Sturgeon, J. A., Fish, S., Dexter, F., Mackey, S., Flood, P. D. 2019; 44 (6): 660–68

  Abstract

  BACKGROUND: The phase III research evaluating migraine prophylaxis therapy (PREEMPT) protocol was developed in low-risk migraine patients. We studied longitudinal response to treatment in a sequential retrospective observational cohort to evaluate predictors of effectiveness in patients with multiple overlapping pain syndromes treated in a quaternary pain management clinic.METHODS: We evaluated indicators of individual response in 402 consecutive chronic migraine patients who provided demographic information and used the Collaborative Health Outcomes Information Registry.RESULTS: The patients were middle aged 47 (38-56) median (IQR) years old and 83% women. They reported multiple complex pain problems with 11 (6-18) regions represented on a pain body map. Evaluated with National Institutes of Health Patient-Reported Outcomes Measurement Information System measures, they reported higher scores for sleep impairment and disturbance, anxiety, depression, fatigue, pain behavior, pain interference and worse function and satisfaction with social roles compared with the general US population; p<0.001for all domains. Within 120days of treatment, 62% of patients reported reduced headache frequency. The best multivariable model developed for prediction of reduced headache frequency in response to treatment included lower treatment number, lower pain interference score, and less depression (p=0.001, 0.002, and 0.009). Depression may have been an obstacle to successful treatment; there was no association between depression score and number of treatments (p=0.54).CONCLUSIONS: Our findings point to the importance of identifying and addressing pain interference and depression early in chronic migraine management and, more broadly, highlights the importance of multidisciplinary evaluation and treatment in chronic migraine.

  View details for DOI 10.1136/rapm-2018-100196

  View details for PubMedID 31101743

• Treatment Strategies for the Opioid-Dependent Patient (vol 21, 45, 2017) CURRENT PAIN AND HEADACHE REPORTS Teckchandani, S., Barad, M. 2018; 22 (3): 21

  Abstract

  The original version of this article contains an error in the gender listing of the first author in the Conflict of Interest statement.

  View details for PubMedID 29511854

• Treatment Strategies for the Opioid-Dependent Patient CURRENT PAIN AND HEADACHE REPORTS Teckchandani, S., Barad, M. 2017; 21 (11): 45

  Abstract

  This review is intended to help the headache physician think through and plan for management issues concerning the use of opioids. We ask the headache physician to consider if there are instances where prescribing or continuing prescriptions of opiates is plausible, and if so, how can the physician proceed as safely as possible. Our goal is to start a conversation regarding the inevitable encounter with a patient on opiates or requesting opiates.The use of opiates in our society has reached a crisis in staggering death and addiction rates. Recent guideline published by the CDC can assist us in developing an algorithmic approach towards opiate use. Recent advances in addiction medicine can also assist us in protecting our patients. Every headache physician will undoubtedly encounter patients on opiates. There still are appropriate reasons to treat patients with opiates. Every headache physician may need to prescribe opiates and they may be indicated. It is important to learn the correct way to approach, manage, and treat patients on opiates.

  View details for PubMedID 28932964

• Effect of Educating the Primary Care Physician About Headache to Help Reduce "Trivial" Referrals and Improve the Number and Quality of "Substantial" Referrals that Truly Need Subspecialty Headache Medicine Care. Current treatment options in neurology Cowan, R., Barad, M. 2017; 19 (7): 25-?

  Abstract

  Technology is likely to play an increasingly important role in the delivery of healthcare as the disparity between provider availability/expertise and patient numbers/needs increases. This article is intended to lend insight into the ways in which technology can facilitate the evaluation of patients with headache disorders and improve the ongoing monitoring of disease progression and response to therapy, following proper diagnosis. While it is not possible to prognosticate the impact of technologies not yet available, the article addresses potential novel usage of currently existing technology to standardize intake, expedite evaluations, ensure adequate history and documentation, and monitoring of patient care.

  View details for DOI 10.1007/s11940-017-0462-5

  View details for PubMedID 28536899

• Complex regional pain syndrome is associated with structural abnormalities in pain-related regions of the human brain. journal of pain Barad, M. J., Ueno, T., Younger, J., Chatterjee, N., Mackey, S. 2014; 15 (2): 197-203

  Abstract

  Complex regional pain syndrome (CRPS) is a chronic condition that involves significant hyperalgesia of the affected limb, typically accompanied by localized autonomic abnormalities and frequently by motor dysfunction. Although central brain systems are thought to play a role in the development and maintenance of CRPS, these systems have not been well characterized. In this study, we used structural magnetic resonance imaging to characterize differences in gray matter volume between patients with right upper extremity CRPS and matched controls. Analyses were carried out using a whole brain voxel-based morphometry approach. The CRPS group showed decreased gray matter volume in several pain-affect regions, including the dorsal insula, left orbitofrontal cortex, and several aspects of the cingulate cortex. Greater gray matter volume in CRPS patients was seen in the bilateral dorsal putamen and right hypothalamus. Correlation analyses with self-reported pain were then performed on the CRPS group. Pain duration was associated with decreased gray matter in the left dorsolateral prefrontal cortex. Pain intensity was positively correlated with volume in the left posterior hippocampus and left amygdala, and negatively correlated with the bilateral dorsolateral prefrontal cortex. Our findings demonstrate that CRPS is associated with abnormal brain system morphology, particularly pain-related sensory, affect, motor, and autonomic systems.This paper presents structural changes in the brains of patients with CRPS, helping us differentiate CRPS from other chronic pain syndromes and furthering our understanding of this challenging disease.

  View details for DOI 10.1016/j.jpain.2013.10.011

  View details for PubMedID 24212070

• Human Response to Unintended Intrathecal Injection of Botulinum Toxin PAIN MEDICINE Carroll, I., Fischbein, N., Barad, M., Mackey, S. 2011; 12 (7): 1094-1097

  Abstract

  Describe the first reported human intrathecal (IT) botulinum toxin injection.Case report.We report here the sequelae to an unintended IT injection of botulinum toxin type B (BTB) in a 60-year-old woman with chronic back pain.Following the IT administration of BTB, the patient experienced the onset of symmetric ascending stocking distribution painful dysesthesias, which persisted for approximately 6 months before receding. Objective neurologic deficits were not appreciated, and analgesic effects were prominently absent.Analgesic actions of botulinum toxins in animals and in humans have led to speculation that IT botulinum toxin might exert significant analgesic effects. The unusual and unexpected subsequent clinical course, neurologic sequelae, dysesthesias, and absence of analgesia suggest that botulinum toxin will not be a therapeutic modality to treat pain as proposed by those studying botulinum toxin in animal models.

  View details for DOI 10.1111/j.1526-4637.2011.01135.x

  View details for Web of Science ID 000292697100016

  View details for PubMedID 21627762

• Serratus muscle stimulation effectively treats notalgia paresthetica caused by long thoracic nerve dysfunction: a case series. Journal of brachial plexus and peripheral nerve injury Wang, C. K., Gowda, A., Barad, M., Mackey, S. C., Carroll, I. R. 2009; 4: 17-?

  Abstract

  Currently, notalgia paresthetica (NP) is a poorly-understood condition diagnosed on the basis of pruritus, pain, or both, in the area medial to the scapula and lateral to the thoracic spine. It has been proposed that NP is caused by degenerative changes to the T2-T6 vertebrae, genetic disposition, or nerve entrapment of the posterior rami of spinal nerves arising at T2-T6. Despite considerable research, the etiology of NP remains unclear, and a multitude of different treatment modalities have correspondingly met with varying degrees of success. Here we demonstrate that NP can be caused by long thoracic nerve injury leading to serratus anterior dysfunction, and that electrical muscle stimulation (EMS) of the serratus anterior can successfully and conservatively treat NP. In four cases of NP with known injury to the long thoracic nerve we performed transcutaneous EMS to the serratus anterior in an area far lateral to the site of pain and pruritus, resulting in significant and rapid pain relief. These findings are the first to identify long thoracic nerve injury as a cause for notalgia paresthetica and electrical muscle stimulation of the serratus anterior as a possible treatment, and we discuss the implications of these findings on better diagnosing and treating notalgia paresthetica.

  View details for DOI 10.1186/1749-7221-4-17

  View details for PubMedID 19772656

  View details for PubMedCentralID PMC2758879