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Zhou JS, Chen Z, Liu YY, Zhong ML, Zhong Q, Wei J, Hu Q, Wang JS, Wang LF. Observation on the Analgesic Effect of Different Doses of a Combination of Esketamine and Dexmedetomidine Administered for Percutaneous Endoscopic Transforaminal Discectomy: A Randomized, Double-Blind Controlled Trial. CNS Drugs 2024; 38:547-558. [PMID: 38573471 DOI: 10.1007/s40263-024-01083-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/10/2024] [Indexed: 04/05/2024]
Abstract
BACKGROUND Percutaneous endoscopic transforaminal discectomy (PETD) is an effective method for treating lumbar disc herniation, and is typically performed under local anesthesia. However, inadequate analgesia during the procedure remains a concern, prompting the search for a medication that can provide optimal pain control with minimal impact on the respiratory and circulatory systems. OBJECTIVES The aim of this study was to observe the effects of different doses of esketamine combined with dexmedetomidine on reducing visual analog scale (VAS) scores during surgical interventions. METHODS One hundred two patients who underwent PETD were randomly divided into a control group (group C: normal saline + dexmedetomidine), an E1 group (0.1 mg kg-1 esketamine + dexmedetomidine), and an E2 group (0.2 mg kg-1 esketamine + dexmedetomidine). The primary outcome was the maximum visual analogue scale (VAS) (score: 0 = no pain and 10 = worst pain) at six time points. The secondary outcomes included the Assessment of Alertness/Sedation Scale (OAA/S) score and mean arterial pressure (BP), heart rate (HR), respiratory rate (RR), and oxygen saturation (SpO2) at 11 time points. The incidence of adverse reactions during and 24 h after the operation and patient satisfaction with the anesthesia were also recorded. RESULTS Compared with those in group C, the VAS scores of patients in groups E1 and E2 were lower at T6, T7, and T9 (P < 0.05). From T4 to T10, the OAA/S scores of the E1 and E2 groups were both lower than those of group C (P < 0.05), and at the T4-T6 time points, the OAA/S score of the E2 group was lower than that of group E1 (P < 0.05). At T4 and T5, the HR and BP of patients in groups E1 and E2 were greater than those in group C (P < 0.05). Compared with those in group C, the incidences of intraoperative illusion, floating sensation, postoperative dizziness, and hyperalgesia in groups E1 and E2 were significantly greater (P < 0.01). There was no significant difference in patient RR, SpO2, or postoperative satisfaction with anesthesia among the three groups (P > 0.05). CONCLUSION The combination of esketamine and dexmedetomidine can reduce VAS scores during certain stages of this type of surgery; it has minimal impact on respiration and circulation. However, this approach is associated with increased incidences of postoperative dizziness and psychiatric side effects, which may also affect patients' compliance with surgical instructions from medical staff. Patient satisfaction was not greater with dexmedetomidine combined with esketamine than with dexmedetomidine alone. TRIAL REGISTRATION http://www.chictr.org.cn . Identifier: ChiCTR2300068206. Date of registration: 10 February 2023.
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Affiliation(s)
- Jian-Shun Zhou
- The First Clinical Medical College of Gannan Medical University, Ganzhou, China
| | - Zhen Chen
- The First Clinical Medical College of Gannan Medical University, Ganzhou, China
| | - Ying-Ying Liu
- The First Clinical Medical College of Gannan Medical University, Ganzhou, China
| | - Mao-Lin Zhong
- Department of Anesthesiology, First Affiliated Hospital of Gannan Medical University, Ganzhou, China
- Ganzhou Key Laboratory of Anesthesiology, Ganzhou, China
| | - Qiong Zhong
- Pain Management, First Affiliated Hospital of Gannan Medical University, Ganzhou, China
| | - Jun Wei
- Pain Management, First Affiliated Hospital of Gannan Medical University, Ganzhou, China
| | - Qian Hu
- The First Clinical Medical College of Gannan Medical University, Ganzhou, China
| | - Jia-Sheng Wang
- The First Clinical Medical College of Gannan Medical University, Ganzhou, China
| | - Li-Feng Wang
- Department of Anesthesiology, First Affiliated Hospital of Gannan Medical University, Ganzhou, China.
- Ganzhou Key Laboratory of Anesthesiology, Ganzhou, China.
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Cao B, Xu Q, Shi Y, Zhao R, Li H, Zheng J, Liu F, Wan Y, Wei B. Pathology of pain and its implications for therapeutic interventions. Signal Transduct Target Ther 2024; 9:155. [PMID: 38851750 PMCID: PMC11162504 DOI: 10.1038/s41392-024-01845-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 04/08/2024] [Accepted: 04/25/2024] [Indexed: 06/10/2024] Open
Abstract
Pain is estimated to affect more than 20% of the global population, imposing incalculable health and economic burdens. Effective pain management is crucial for individuals suffering from pain. However, the current methods for pain assessment and treatment fall short of clinical needs. Benefiting from advances in neuroscience and biotechnology, the neuronal circuits and molecular mechanisms critically involved in pain modulation have been elucidated. These research achievements have incited progress in identifying new diagnostic and therapeutic targets. In this review, we first introduce fundamental knowledge about pain, setting the stage for the subsequent contents. The review next delves into the molecular mechanisms underlying pain disorders, including gene mutation, epigenetic modification, posttranslational modification, inflammasome, signaling pathways and microbiota. To better present a comprehensive view of pain research, two prominent issues, sexual dimorphism and pain comorbidities, are discussed in detail based on current findings. The status quo of pain evaluation and manipulation is summarized. A series of improved and innovative pain management strategies, such as gene therapy, monoclonal antibody, brain-computer interface and microbial intervention, are making strides towards clinical application. We highlight existing limitations and future directions for enhancing the quality of preclinical and clinical research. Efforts to decipher the complexities of pain pathology will be instrumental in translating scientific discoveries into clinical practice, thereby improving pain management from bench to bedside.
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Affiliation(s)
- Bo Cao
- Department of General Surgery, First Medical Center, Chinese PLA General Hospital, Beijing, 100853, China
| | - Qixuan Xu
- Department of General Surgery, First Medical Center, Chinese PLA General Hospital, Beijing, 100853, China
- Medical School of Chinese PLA, Beijing, 100853, China
| | - Yajiao Shi
- Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education/National Health Commission, Peking University, Beijing, 100191, China
| | - Ruiyang Zhao
- Department of General Surgery, First Medical Center, Chinese PLA General Hospital, Beijing, 100853, China
- Medical School of Chinese PLA, Beijing, 100853, China
| | - Hanghang Li
- Department of General Surgery, First Medical Center, Chinese PLA General Hospital, Beijing, 100853, China
- Medical School of Chinese PLA, Beijing, 100853, China
| | - Jie Zheng
- Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education/National Health Commission, Peking University, Beijing, 100191, China
| | - Fengyu Liu
- Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education/National Health Commission, Peking University, Beijing, 100191, China.
| | - You Wan
- Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education/National Health Commission, Peking University, Beijing, 100191, China.
| | - Bo Wei
- Department of General Surgery, First Medical Center, Chinese PLA General Hospital, Beijing, 100853, China.
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3
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Mills EP, Bosma RL, Rogachov A, Cheng JC, Osborne NR, Kim JA, Besik A, Bhatia A, Davis KD. Pretreatment Brain White Matter Integrity Associated With Neuropathic Pain Relief and Changes in Temporal Summation of Pain Following Ketamine. THE JOURNAL OF PAIN 2024:104536. [PMID: 38615801 DOI: 10.1016/j.jpain.2024.104536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 03/07/2024] [Accepted: 04/09/2024] [Indexed: 04/16/2024]
Abstract
Neuropathic pain (NP) is a prevalent condition often associated with heightened pain responsiveness suggestive of central sensitization. Neuroimaging biomarkers of treatment outcomes may help develop personalized treatment strategies, but white matter (WM) properties have been underexplored for this purpose. Here we assessed whether WM pathways of the default mode network (DMN: medial prefrontal cortex [mPFC], posterior cingulate cortex, and precuneus) and descending pain modulation system (periaqueductal gray [PAG]) are associated with ketamine analgesia and attenuated temporal summation of pain (TSP, reflecting central sensitization) in NP. We used a fixel-based analysis of diffusion-weighted imaging data to evaluate WM microstructure (fiber density [FD]) and macrostructure (fiber bundle cross-section) within the DMN and mPFC-PAG pathways in 70 individuals who underwent magnetic resonance imaging and TSP testing; 35 with NP who underwent ketamine treatment and 35 age- and sex-matched pain-free individuals. Individuals with NP were assessed before and 1 month after treatment; those with ≥30% pain relief were considered responders (n = 18), or otherwise as nonresponders (n = 17). We found that WM structure within the DMN and mPFC-PAG pathways did not differentiate responders from nonresponders. However, pretreatment FD in the anterior limb of the internal capsule correlated with pain relief (r=.48). Moreover, pretreatment FD in the DMN (left mPFC-precuneus/posterior cingulate cortex; r=.52) and mPFC-PAG (r=.42) negatively correlated with changes in TSP. This suggests that WM microstructure in the DMN and mPFC-PAG pathway is associated with the degree to which ketamine reduces central sensitization. Thus, fixel metrics of WM structure may hold promise to predict ketamine NP treatment outcomes. PERSPECTIVE: We used advanced fixel-based analyses of MRI diffusion-weighted imaging data to identify pretreatment WM microstructure associated with ketamine outcomes, including analgesia and markers of attenuated central sensitization. Exploring associations between brain structure and treatment outcomes could contribute to a personalized approach to treatment for individuals with NP.
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Affiliation(s)
- Emily P Mills
- Division of Brain, Imaging, and Behaviour, Krembil Brain Institute, University Health Network, Toronto, Ontario, Canada
| | - Rachael L Bosma
- Division of Brain, Imaging, and Behaviour, Krembil Brain Institute, University Health Network, Toronto, Ontario, Canada
| | - Anton Rogachov
- Division of Brain, Imaging, and Behaviour, Krembil Brain Institute, University Health Network, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Joshua C Cheng
- Division of Brain, Imaging, and Behaviour, Krembil Brain Institute, University Health Network, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Natalie R Osborne
- Division of Brain, Imaging, and Behaviour, Krembil Brain Institute, University Health Network, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Junseok A Kim
- Division of Brain, Imaging, and Behaviour, Krembil Brain Institute, University Health Network, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Ariana Besik
- Division of Brain, Imaging, and Behaviour, Krembil Brain Institute, University Health Network, Toronto, Ontario, Canada
| | - Anuj Bhatia
- Department of Anesthesia and Pain Management, University Health Network, Toronto, Ontario, Canada; Department of Anesthesia, University of Toronto, Toronto, Ontario, Canada
| | - Karen D Davis
- Division of Brain, Imaging, and Behaviour, Krembil Brain Institute, University Health Network, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada; Department of Surgery, University of Toronto, Toronto, Ontario, Canada
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Bertotti G, Gil-Martínez A, Matesanz-García L, Angulo-Díaz-Parreño S, Rodríguez-Vico J, Díaz-de-Terán J, Elizagaray-García JI. Somatosensory Profiling of Patients With Cluster Headache: A Systematic Review and Meta-analysis. THE JOURNAL OF PAIN 2024:S1526-5900(24)00379-1. [PMID: 38367655 DOI: 10.1016/j.jpain.2024.02.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 01/25/2024] [Accepted: 02/06/2024] [Indexed: 02/19/2024]
Abstract
The objectives were 1) to synthesize quantitative sensory testing results in cluster headache (CH) patients and to identify somatosensory differences from healthy subjects (HS), and 2) between symptomatic and asymptomatic sides in CH patients. Two independent reviewers conducted a literature search in MEDLINE, EMBASE, Web of Science, and CINAHL databases. Studies with observational designs were included. Methodological quality and risk of bias were assessed with the Newcastle Ottawa Scale. The selected studies underwent qualitative and quantitative analyses. The qualitative analysis showed inconsistent findings among multiple studies. Meta-analysis showed lower pressure pain thresholds (PPTs) on the symptomatic side of CH patients than HS in V2 (standardized mean difference [SMD] -1.01 [95% confidence interval (CI) -1.79, -.23], P = .01, I2 = 73%, n = 114), V3 (SMD -1 [95% CI -1.54, .45], P < .01, I2 = 82%, n = 354), and cervical region (SMD -1.25 [95% CI -2.07, -.44], P < .01, I2 = 84%, n = 194). Furthermore, lower PPTs than those detected in HS were found on the asymptomatic side in V3 (SMD -.77 [95% CI -1.27, -.27], P < .01, I2 = 79%, n = 354) and in the cervical region (SMD -1.13 [95% CI -1.97, -.3], P < .01, I2 = 85%, n = 194). However, no differences were found in V1 or the extratrigeminal points between these groups. No significant changes were found between symptomatic and asymptomatic sides in trigeminal and extratrigeminal regions. Mechanical hyperalgesia in the trigemino-cervical region of patients with CH could suggest the presence of central pain mechanisms. These results are of clinical relevance because their presence could be associated with a poorer prognosis, chronification, and treatment response. PERSPECTIVES: This study provides consistent findings on the somatosensory profile characterizing patients with CH. Clinicians should assess PPTs and other quantitative sensory testing variables in the trigeminal and extratrigeminal (cervical) regions.
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Affiliation(s)
- Gabriele Bertotti
- School of Physiotherapy, Faculty of Health Sciences, Universidad Francisco de Vitoria, Madrid, Spain; CranioSPain Research Group, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid, Spain
| | - Alfonso Gil-Martínez
- CranioSPain Research Group, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid, Spain; Department of Physiotherapy, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid, Spain; Unit of Physiotherapy, Hospital Universitario La Paz-Carlos III, IdiPAZ, Madrid, Spain
| | - Luis Matesanz-García
- CranioSPain Research Group, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid, Spain; Department of Physiotherapy, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid, Spain
| | | | - Jaime Rodríguez-Vico
- Headache Unit, Neurology Department, Hospital Universitario Fundación Jiménez Díaz, Madrid, Spain
| | - Javier Díaz-de-Terán
- CranioSPain Research Group, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid, Spain; Headache Unit, Neurology Department, Hospital Universitario La Paz-Carlos III, IdiPAZ, Madrid, Spain
| | - Juan Ignacio Elizagaray-García
- CranioSPain Research Group, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid, Spain; Department of Physiotherapy, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid, Spain
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5
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Mangnus TJP, Dirckx M, Huygen FJPM. Different Types of Pain in Complex Regional Pain Syndrome Require a Personalized Treatment Strategy. J Pain Res 2023; 16:4379-4391. [PMID: 38162406 PMCID: PMC10757771 DOI: 10.2147/jpr.s432209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Accepted: 11/13/2023] [Indexed: 01/03/2024] Open
Abstract
Complex regional pain syndrome (CRPS) is a debilitating painful state of an extremity that can develop after trauma. CRPS is diagnosed by the new International Association for the Study of Pain (IASP) diagnostic criteria for CRPS. The syndrome is characterized by continuing regional pain with abnormal sensory, motor, sudomotor, vasomotor, edema, and/or trophic signs. The clinical presentation of CRPS can be very heterogeneous because CRPS is a multi-mechanism syndrome. Therefore, mechanism-based subgroups have been suggested to personalize treatment for CRPS. Additionally, the presentation of symptom pain may also be able to identify different subgroups of CRPS. In this review, the types of pain recognized by the IASP-nociceptive, neuropathic, and nociplastic pain-will be discussed as possible subgroups for CRPS. Each pain type should be identified in CRPS patients, with a thorough history taking, physical examination, and diagnostic tests or (novel) biomarkers to optimize treatment effectiveness. Over the course of the syndrome, patients with CRPS probably experience more than one distinct pain type. Therefore, pain specialists should be alert to not only adjust their treatment if underlying pathophysiologic mechanisms tend to change but also to personalize the treatment of the associated type of pain in the CRPS patient.
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Affiliation(s)
- Thomas J P Mangnus
- Department of Anesthesiology, Center for Pain Medicine, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Maaike Dirckx
- Department of Anesthesiology, Center for Pain Medicine, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Frank J P M Huygen
- Department of Anesthesiology, Center for Pain Medicine, Erasmus MC University Medical Center, Rotterdam, the Netherlands
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6
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Rosner J, de Andrade DC, Davis KD, Gustin SM, Kramer JLK, Seal RP, Finnerup NB. Central neuropathic pain. Nat Rev Dis Primers 2023; 9:73. [PMID: 38129427 DOI: 10.1038/s41572-023-00484-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/21/2023] [Indexed: 12/23/2023]
Abstract
Central neuropathic pain arises from a lesion or disease of the central somatosensory nervous system such as brain injury, spinal cord injury, stroke, multiple sclerosis or related neuroinflammatory conditions. The incidence of central neuropathic pain differs based on its underlying cause. Individuals with spinal cord injury are at the highest risk; however, central post-stroke pain is the most prevalent form of central neuropathic pain worldwide. The mechanisms that underlie central neuropathic pain are not fully understood, but the pathophysiology likely involves intricate interactions and maladaptive plasticity within spinal circuits and brain circuits associated with nociception and antinociception coupled with neuronal hyperexcitability. Modulation of neuronal activity, neuron-glia and neuro-immune interactions and targeting pain-related alterations in brain connectivity, represent potential therapeutic approaches. Current evidence-based pharmacological treatments include antidepressants and gabapentinoids as first-line options. Non-pharmacological pain management options include self-management strategies, exercise and neuromodulation. A comprehensive pain history and clinical examination form the foundation of central neuropathic pain classification, identification of potential risk factors and stratification of patients for clinical trials. Advanced neurophysiological and neuroimaging techniques hold promise to improve the understanding of mechanisms that underlie central neuropathic pain and as predictive biomarkers of treatment outcome.
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Affiliation(s)
- Jan Rosner
- Danish Pain Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
- Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Daniel C de Andrade
- Center for Neuroplasticity and Pain (CNAP), Department of Health Science and Technology, Faculty of Medicine, Aalborg University, Aalborg, Denmark
| | - Karen D Davis
- Division of Brain, Imaging and Behaviour, Krembil Brain Institute, Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada
- Department of Surgery and Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Sylvia M Gustin
- Centre for Pain IMPACT, Neuroscience Research Australia, Sydney, New South Wales, Australia
- NeuroRecovery Research Hub, School of Psychology, University of New South Wales, Sydney, New South Wales, Australia
| | - John L K Kramer
- International Collaboration on Repair Discoveries, ICORD, University of British Columbia, Vancouver, Canada
- Department of Anaesthesiology, Pharmacology & Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, Canada
| | - Rebecca P Seal
- Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Departments of Neurobiology and Otolaryngology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Nanna B Finnerup
- Danish Pain Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.
- Department of Neurology, Aarhus University Hospital, Aarhus, Denmark.
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Wang D, Moosa S, Ishaque M, Finan P, Quigg M, Jeffrey Elias W, Liu CC. Painful Cutaneous Laser Stimulation for Temporal Summation of Pain Assessment. THE JOURNAL OF PAIN 2023; 24:2283-2293. [PMID: 37468022 DOI: 10.1016/j.jpain.2023.07.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 06/26/2023] [Accepted: 07/07/2023] [Indexed: 07/21/2023]
Abstract
Variability in pain sensitivity arises not only from the differences in peripheral sensory receptors but also from the differences in central nervous system (CNS) pain inhibition and facilitation mechanisms. Temporal summation of pain (TSP) is an experimental protocol commonly used in human studies of pain facilitation but is susceptible to confounding when elicited with the skin-contact thermode, which adds the responses of touch-related Aβ low-threshold mechanoreceptors to nociceptive receptors. In the present study, we evaluate an alternative method involving the use of a contactless cutaneous laser for TSP assessment. We show that repetitive laser stimulations with a one second inter-stimulus interval evoked reliable TSP responses in a significant proportion of healthy subjects (N = 36). Female subjects (N = 18) reported greater TSP responses than male subjects confirming earlier studies of sex differences in central nociceptive excitability. Furthermore, repetitive laser stimulations during TSP induction elicited increased time-frequency electroencephalography (EEG) responses. The present study demonstrates that repetitive laser stimulation may be an alternative to skin-contact methods for TSP assessment in patients and healthy controls. PERSPECTIVE: Temporal summation of pain (TSP) is an experimental protocol commonly used in human studies of pain facilitation. We show that contactless cutaneous laser stimulation is a reliable alternative to the skin contact approaches during TSP assessment.
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Affiliation(s)
- Dan Wang
- Departments of Neurological Surgery, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Shayan Moosa
- Departments of Neurological Surgery, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Mariam Ishaque
- Departments of Neurological Surgery, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Patrick Finan
- Departments of Anesthesiology, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Mark Quigg
- Departments of Neurology, University of Virginia School of Medicine, Charlottesville, Virginia
| | - W Jeffrey Elias
- Departments of Neurological Surgery, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Chang-Chia Liu
- Departments of Neurological Surgery, University of Virginia School of Medicine, Charlottesville, Virginia
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Lawn T, Sendel M, Baron R, Vollert J. Beyond biopsychosocial: The keystone mechanism theory of pain. Brain Behav Immun 2023; 114:187-192. [PMID: 37625555 DOI: 10.1016/j.bbi.2023.08.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 07/13/2023] [Accepted: 08/20/2023] [Indexed: 08/27/2023] Open
Abstract
Pain is a deeply personal experience, with interindividual differences in its chronification and treatment presenting a formidable healthcare challenge. The biopsychosocial model (BPSm) has been hugely influential within nascent attempts at precision pain medicine, steering the field away from a reductionist biomechanical viewpoint and emphasising complex interactions of biological, psychological, and social factors which shape the individuality of pain. However, despite offering a strong theoretical foundation and holistic perspective, we contend that the BPSm remains limited in its capacity to deliver truly mechanistically informed treatment of pain. We therefore propose the keystone model of pain which offers a pragmatic balance between the dimensionality expansive BPSm and overly reductive approaches, providing both theoretical and practical advantages for the transition from treating populations to individual people.
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Affiliation(s)
- Timothy Lawn
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
| | - Manon Sendel
- Division of Neurological Pain Research and Therapy, Department of Neurology, University Hospital of Schleswig-Holstein, Campus Kiel, Germany
| | - Ralf Baron
- Division of Neurological Pain Research and Therapy, Department of Neurology, University Hospital of Schleswig-Holstein, Campus Kiel, Germany
| | - Jan Vollert
- Division of Neurological Pain Research and Therapy, Department of Neurology, University Hospital of Schleswig-Holstein, Campus Kiel, Germany; Department of Anaesthesiology, Intensive Care and Pain Medicine, University Hospital Muenster, Germany; Pain Research, Department of Surgery and Cancer, Imperial College, London, UK; Neurophysiology, Mannheim Centre for Translational Neuroscience MCTN, Medical Faculty Mannheim, Ruprecht Karls University, Heidelberg, Germany
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9
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Bao JD, Rosser MA, Park SH, Baker AK, Martucci KT. Interplay between noxious heat sensitivity and temporal summation magnitude in patients with fibromyalgia and long-term opioid use. Front Neurosci 2023; 17:1275921. [PMID: 37901425 PMCID: PMC10600517 DOI: 10.3389/fnins.2023.1275921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 09/26/2023] [Indexed: 10/31/2023] Open
Abstract
Introduction In chronic pain conditions such as fibromyalgia (FM), pain amplification within the central nervous system, or "central sensitization," may contribute to the development and maintenance of chronic pain. Chronic pain treatments include opioid therapy, and opioid therapy may maladaptively increase central sensitization, particularly in patients who take opioids long-term. However, it has remained unknown how central sensitization is impacted in patients who use opioids long-term. Methods To investigate how long-term opioid therapy affects central sensitization, we used the validated measure of temporal summation. The temporal summation measurement consists of applying a series of noxious stimuli to a patient's skin and then calculating changes in the patient's pain rating to each stimulus. Using this measurement, we evaluated temporal summation in study participants with fibromyalgia who take opioids long-term (i.e., greater than 90 days duration; n = 24, opioid-FM). We compared opioid-FM responses to 2 control groups: participants with fibromyalgia who do not take opioids (n = 33, non-opioid FM), and healthy controls (n = 31). For the temporal summation measurement, we applied a series of 10 noxious heat stimuli (sensitivity-adjusted temperatures) to the ventral forearm (2s duration of each stimulus, applied once every 3 s). Additionally, we collected responses to standard pain and cognitive-affective questionnaires to assess pain severity and other factors. Results and discussion Group differences in sensitivity-adjusted stimulus temperatures were observed, with only the non-opioid FM group requiring significantly lower stimulus temperatures (The opioid-FM group also required lower temperatures, but not significantly different from the control group). However, all 3 groups exhibited similar magnitudes of temporal summation. Across combined FM groups, temporal summation negatively correlated with pain severity (r = -0.31, p = 0.021). Within the opioid-FM group, higher pain sensitivity to heat (i.e., lower sensitivity-adjusted temperatures) showed a trend relationship with higher opioid dosage (r = -0.45, p = 0.036), potentially reflective of opioid-related hyperalgesia. Our findings also indicated that heightened pain severity may skew sensitivity-adjusted temporal summation, thereby limiting its utility for measuring central sensitization. Overall, in participants taking opioids, temporal summation may be influenced by hypersensitivity to heat pain, which appeared to vary with opioid dosage.
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Affiliation(s)
- Jason D. Bao
- Human Affect and Pain Neuroscience Laboratory, Department of Anesthesiology, Duke University Medical Center, Durham, NC, United States
- Center for Translational Pain Medicine, Duke University Medical Center, Durham, NC, United States
| | - Morgan A. Rosser
- Department of Anesthesiology, Biostatistics Group, Duke University School of Medicine, Durham, NC, United States
| | - Su Hyoun Park
- Human Affect and Pain Neuroscience Laboratory, Department of Anesthesiology, Duke University Medical Center, Durham, NC, United States
- Center for Translational Pain Medicine, Duke University Medical Center, Durham, NC, United States
| | - Anne K. Baker
- Human Affect and Pain Neuroscience Laboratory, Department of Anesthesiology, Duke University Medical Center, Durham, NC, United States
- Center for Translational Pain Medicine, Duke University Medical Center, Durham, NC, United States
| | - Katherine T. Martucci
- Human Affect and Pain Neuroscience Laboratory, Department of Anesthesiology, Duke University Medical Center, Durham, NC, United States
- Center for Translational Pain Medicine, Duke University Medical Center, Durham, NC, United States
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10
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Lepping RJ, Hoffart CM, Bruce AS, Taylor JM, Mardis NJ, Lim SL, Wallace DP. Pediatric Neural Changes to Physical and Emotional Pain After Intensive Interdisciplinary Pain Treatment: A Pilot Study. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.10.03.23295921. [PMID: 37873243 PMCID: PMC10593005 DOI: 10.1101/2023.10.03.23295921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
Brain areas activated during pain can contribute to enhancing or reducing the pain experience, showing a potential connection between chronic pain and the neural response to pain in adolescents and youth. This study examined changes in brain activation associated with experiencing physical pain, and the observation of physical and emotional pain in others, by using functional magnetic resonance imaging (fMRI) before and after intensive interdisciplinary pain treatment (IIPT). Eighteen youth (age 14 to 18) with widespread chronic pain completed fMRI testing before and after IIPT to assess changes in brain activation in response to physical and emotional pain. Broadly, brain activation changes were observed in frontal, somatosensory, and limbic regions. These changes suggest improvements in descending pain modulation via thalamus and caudate, and the different pattern of brain activation after treatment suggests better discrimination between physical and emotional pain. Brain activation changes were also correlated with improvements in clinical outcomes of catastrophizing (reduced activation in right caudate, right mid-cingulate, and postcentral gyrus) and pain-related disability (increased activation in precentral gyrus, left hippocampus, right middle occipital cortex, and left superior frontal gyrus). These changes support interpretation that reduced brain protective responses to pain were associated with treatment-related improvements. This pilot study highlights the need for larger trials designed to better understand the brain mechanisms involved in pediatric widespread pain treatment.
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Affiliation(s)
- Rebecca J Lepping
- Department of Neurology, University of Kansas Medical Center, Kansas City, KS, USA
- Hoglund Biomedical Imaging Center, University of Kansas Medical Center, Kansas City, KS, USA
| | - Cara M Hoffart
- Pain Management, Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO, USA; Center for Children's Healthy Lifestyles & Nutrition, Kansas City, MO, USA; Department of Pediatrics, University of Missouri-Kansas City School of Medicine, Kansas City, MO, USA
| | - Amanda S Bruce
- Pediatrics, University of Kansas Medical Center, USA; Center for Children's Healthy Lifestyles and Nutrition, Children's Mercy Hospital, Kansas City, MO, USA
| | - Jasmine M Taylor
- Department of Neurology, University of Kansas Medical Center, Kansas City, KS, USA
- Hoglund Biomedical Imaging Center, University of Kansas Medical Center, Kansas City, KS, USA
| | - Neil J Mardis
- Pediatric Radiology, Children's Mercy, University of Missouri-Kansas City, Kansas City, MO, USA
| | - Seung-Lark Lim
- Department of Psychology, University of Missouri-Kansas City, Kansas City, MO, USA
| | - Dustin P Wallace
- Pain Management, Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO, USA; Center for Children's Healthy Lifestyles & Nutrition, Kansas City, MO, USA; Department of Pediatrics, University of Missouri-Kansas City School of Medicine, Kansas City, MO, USA
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11
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Alsouhibani A, Speck P, Cole EF, Mustin DE, Li Y, Barron JR, Orenstein LAV, Harper DE. Quantitative Sensory Testing to Characterize Sensory Changes in Hidradenitis Suppurativa Skin Lesions. JAMA Dermatol 2023; 159:1102-1111. [PMID: 37702999 PMCID: PMC10500434 DOI: 10.1001/jamadermatol.2023.3243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 04/25/2023] [Indexed: 09/14/2023]
Abstract
Importance Pain is the most impactful symptom in patients with hidradenitis suppurativa (HS). Characterization of sensory profiles may improve understanding of pain mechanisms in HS and facilitate identification of effective pain management strategies. Objective To characterize somatosensory profiles in patients with HS at clinically affected and nonaffected sites compared with pain-free reference data. Design, Setting, and Participants This cross-sectional study was conducted at the Emory University Dermatology Clinic. It was hypothesized (1) that patients with HS would demonstrate hypersensitivity to pain in HS lesions and (2) that some patients would have sensory profiles consistent with complex pain mechanisms. Therefore, adults with dermatologist-diagnosed HS and at least 1 painful HS lesion at the time of testing were enrolled between September 10, 2020, and March 21, 2022. Patients with other diagnoses contributing to pain or neuropathy were excluded. Data analysis was conducted between March and April 2022. Exposure Quantitative sensory testing was performed on HS lesions and control skin according to a standardized protocol. Main Outcomes and Measures Quantitative sensory testing outcomes included innocuous thermal and mechanical sensitivity (cold, warmth, and light touch detection thresholds), noxious thermal and mechanical sensitivity (cold, heat, pinprick, and deep pressure pain thresholds and suprathreshold pinprick sensitivity), temporal summation of pinprick, paradoxical thermal sensations, and dynamic mechanical allodynia (pain upon light stroking of the skin). Sensitivity in HS lesions was compared with sensitivity in a control location (the hand) and in pain-free controls using t tests. Results This study included 20 participants with a median age of 35.5 (IQR, 30.0-46.5) years, the majority of whom were women (15 [75%]). In terms of race and ethnicity, 2 participants (10%) self-identified as Asian, 11 (55%) as Black, 6 (30%) as White, and 1 (5%) as more than 1 race or ethnicity. Compared with site-specific reference values from healthy, pain-free control participants, HS lesions were insensitive to innocuous cold and warmth, noxious heat, and light touch (t = -5.69, -10.20, -3.84, and 4.46, respectively; all P < .001). In contrast, HS lesions also demonstrated significant hypersensitivity to deep pressure pain (t = 8.36; P < .001) and cutaneous pinprick (t = 2.07; P = .046). Hypersensitivity to deep pressure pain was also observed in the control site (t = 5.85; P < .001). A subset of patients with HS displayed changes in pain processing that are often seen in neuropathic and nociplastic pain conditions, including hypersensitivity to repetitive pinprick (5 [26%]), paradoxical thermal sensations (3 [15%]), and pain upon light stroking of the skin (10 [50%]). Conclusions and Relevance The findings of this cross-sectional study suggest that HS involves local changes in the skin or its free nerve endings, possibly leading to peripheral neuropathy and alterations in the transduction of innocuous and noxious thermal and mechanical stimuli. For some patients, central nervous system changes in somatosensory processing may also occur, but confirmatory evidence is needed. Better understanding of neuropathic and nociplastic mechanisms in HS pain could lead to individually tailored treatments.
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Affiliation(s)
- Ali Alsouhibani
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, Georgia
- Department of Physical Therapy, College of Medical Rehabilitation, Qassim University, Buraydah, Saudi Arabia
| | - Patrick Speck
- Department of Dermatology, Emory University School of Medicine, Atlanta, Georgia
| | - Emily F. Cole
- Department of Dermatology, Emory University School of Medicine, Atlanta, Georgia
| | - Danielle E. Mustin
- Department of Dermatology, Emory University School of Medicine, Atlanta, Georgia
| | - Yiwen Li
- Department of Dermatology, Emory University School of Medicine, Atlanta, Georgia
| | - Jason R. Barron
- Department of Dermatology, Emory University School of Medicine, Atlanta, Georgia
| | | | - Daniel E. Harper
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, Georgia
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12
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Bouhassira D, Attal N. Personalized treatment of neuropathic pain: Where are we now? Eur J Pain 2023; 27:1084-1098. [PMID: 37114461 DOI: 10.1002/ejp.2120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 04/07/2023] [Accepted: 04/15/2023] [Indexed: 04/29/2023]
Abstract
BACKGROUND The treatment of neuropathic pain remains a major unmet need that the development of personalized and refined treatment strategies may contribute to address. DATABASE In this narrative review, we summarize the various approaches based on objective biomarkers or clinical markers that could be used. RESULTS In principle, the validation of objective biomarkers would be the most robust approach. However, although promising results have been reported demonstrating a potential value of genomics, anatomical or functional markers, the clinical validation of these markers has only just begun. Thus, most of the strategies documented to date have been based on the development of clinical markers. In particular, many studies have suggested that the identification of specific subgroups of patients presenting with specific combinations of symptoms and signs would be a relevant approach. Two main approaches have been used to identify relevant sensory profiles: quantitative sensory testing and specific patients reported outcomes based on description of pain qualities. CONCLUSION We discuss here the advantages and limitations of these approaches, which are not mutually exclusive. SIGNIFICANCE Recent data indicate that various new treatment strategies based on predictive biological and/or clinical markers could be helpful to better personalized and therefore improve the management of neuropathic pain.
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Affiliation(s)
- Didier Bouhassira
- Inserm U987, UVSQ-Paris-Saclay University, Ambroise Pare Hospital, Boulogne-Billancourt, France
| | - Nadine Attal
- Inserm U987, UVSQ-Paris-Saclay University, Ambroise Pare Hospital, Boulogne-Billancourt, France
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13
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Zhou JS, Peng GF, Liang WD, Chen Z, Liu YY, Wang BY, Guo ML, Deng YL, Ye JM, Zhong ML, Wang LF. Recent advances in the study of anesthesia-and analgesia-related mechanisms of S-ketamine. Front Pharmacol 2023; 14:1228895. [PMID: 37781698 PMCID: PMC10539608 DOI: 10.3389/fphar.2023.1228895] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 09/04/2023] [Indexed: 10/03/2023] Open
Abstract
Ketamine is a racemic mixture of equal amounts of R-ketamine and S-ketamine and is well known to anesthesiologists for its unique dissociative anesthetic properties. The pharmacological properties of ketamine, namely, its sympathetic excitation, mild respiratory depression, and potent analgesia, are still highly valued in its use as an anesthetic for some patients. In particular, since its advent, S-ketamine has been widely used as an anesthetic in many countries due to its increased affinity for NMDA receptors and its enhanced anesthetic and analgesic effects. However, the anesthetic and analgesic mechanisms of S-ketamine are not fully understood. In addition to antagonizing NMDA receptors, a variety of other receptors or channels may be involved, but there are no relevant mechanistic summaries in the literature. Therefore, the purpose of this paper is to review the mechanisms of action of S-ketamine on relevant receptors and systems in the body that result in its pharmacological properties, such as anesthesia and analgesia, with the aim of providing a reference for its clinical applications and research.
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Affiliation(s)
- Jian-shun Zhou
- The First Clinical Medical College of Gannan Medical University, Ganzhou, China
| | - Guan-fa Peng
- The First Clinical Medical College of Gannan Medical University, Ganzhou, China
| | - Wei-dong Liang
- Department of Anesthesiology, First Affiliated Hospital of Gannan Medical University, Ganzhou, China
- Ganzhou Key Laboratory of Anesthesiology, Ganzhou, China
| | - Zhen Chen
- The First Clinical Medical College of Gannan Medical University, Ganzhou, China
| | - Ying-ying Liu
- The First Clinical Medical College of Gannan Medical University, Ganzhou, China
| | - Bing-yu Wang
- The First Clinical Medical College of Gannan Medical University, Ganzhou, China
| | - Ming-ling Guo
- The First Clinical Medical College of Gannan Medical University, Ganzhou, China
| | - Yun-ling Deng
- Department of Anesthesiology, First Affiliated Hospital of Gannan Medical University, Ganzhou, China
- Ganzhou Key Laboratory of Anesthesiology, Ganzhou, China
| | - Jun-ming Ye
- Department of Anesthesiology, First Affiliated Hospital of Gannan Medical University, Ganzhou, China
- Ganzhou Key Laboratory of Anesthesiology, Ganzhou, China
| | - Mao-lin Zhong
- Department of Anesthesiology, First Affiliated Hospital of Gannan Medical University, Ganzhou, China
- Ganzhou Key Laboratory of Anesthesiology, Ganzhou, China
| | - Li-feng Wang
- Department of Anesthesiology, First Affiliated Hospital of Gannan Medical University, Ganzhou, China
- Ganzhou Key Laboratory of Anesthesiology, Ganzhou, China
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14
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Thakkar B, Peterson CL, Acevedo EO. Prolonged continuous theta burst stimulation increases motor corticospinal excitability and intracortical inhibition in patients with neuropathic pain: An exploratory, single-blinded, randomized controlled trial. Neurophysiol Clin 2023; 53:102894. [PMID: 37659135 PMCID: PMC10592401 DOI: 10.1016/j.neucli.2023.102894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 06/29/2023] [Accepted: 06/29/2023] [Indexed: 09/04/2023] Open
Abstract
OBJECTIVES A new paradigm for Transcranial Magnetic Stimulation (TMS), referred to as prolonged continuous theta burst stimulation (pcTBS), has recently received attention in the literature because of its advantages over high frequency repetitive TMS (HF-rTMS). Clinical advantages include less time per intervention session and the effects appear to be more robust and reproducible than HF-rTMS to modulate cortical excitability. HF-rTMS targeted at the primary motor cortex (M1) has demonstrated analgesic effects in patients with neuropathic pain but their mechanisms of action are unclear and pcTBS has been studied in healthy subjects only. This study examined the neural mechanisms that have been proposed to play a role in explaining the effects of pcTBS targeted at the M1 and DLPFC brain regions in neuropathic pain (NP) patients with Type 2 diabetes. METHODS Forty-two patients with painful diabetic neuropathy were randomized to receive a single session of pcTBS targeted at the left M1 or left DLPFC. pcTBS stimulation consisted of 1,200 pulses delivered in 1 min and 44 s with a 35-45 min gap between sham and active pcTBS stimulation. Both the activity of the descending pain system which was examined using conditioned pain modulation and the activity of the ascending pain system which was assessed using temporal summation of pain were recorded using a handheld pressure algometer by measuring pressure pain thresholds. The amplitude of the motor evoked potential (MEP) was used to measure motor corticospinal excitability and GABA activity was assessed using short (SICI) and long intracortical inhibition (LICI). All these measurements were performed at baseline and post-pcTBS stimulation. RESULTS Following a single session of pcTBS targeted at M1 and DLPFC, there was no change in BPI-DN scores and on the activity of the descending (measured using conditioned pain modulation) and ascending pain systems (measured using temporal summation of pain) compared to baseline but there was a significant improvement of >13% in perception of acute pain intensity, increased motor corticospinal excitability (measured using MEP amplitude) and intracortical inhibition (measured using SICI and LICI). CONCLUSION In patients with NP, a single session of pcTBS targeted at the M1 and DLPFC modulated the neurophysiological mechanisms related to motor corticospinal excitability and neurochemical mechanisms linked to GABA activity, but it did not modulate the activity of the ascending and descending endogenous modulatory systems. In addition, although BPI-DN scores did not change, there was a 13% improvement in self-reported perception of acute pain intensity.
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Affiliation(s)
- Bhushan Thakkar
- Department of Physical Therapy, Virginia Commonwealth University, Richmond, VA, United States.
| | - Carrie L Peterson
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA, United States
| | - Edmund O Acevedo
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA, United States
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15
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Mangnus TJP, Dirckx M, Bharwani KD, Baart SJ, Siepman TAM, Redekop K, Dik WA, de Vos CC, Huygen FJPM. Intermittent versus continuous esketamine infusions for long-term pain modulation in complex regional pain syndrome: protocol of a randomized controlled non-inferiority study (KetCRPS-2). BMC Musculoskelet Disord 2023; 24:239. [PMID: 36991381 DOI: 10.1186/s12891-023-06258-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 02/20/2023] [Indexed: 03/31/2023] Open
Abstract
BACKGROUND Complex regional pain syndrome (CRPS) is a chronic pain condition of an extremity. While achieving pain relief in CRPS is challenging, esketamine infusions can accomplish pain relief for several weeks post-infusion in a subgroup of CRPS patients. Unfortunately, CRPS esketamine protocols are very heterogeneous in advice on dosage, administration and treatment setting. Currently, no trials are available that study differences between intermittent and continuous esketamine infusions for CRPS. With the current situation of bed shortages, it is difficult to admit patients for several consecutive days for inpatient esketamine treatments. In this study, we investigate whether 6 intermittent outpatient esketamine treatments are not inferior to a continuous 6-day inpatient esketamine treatment in establishing pain relief. In addition, several secondary study parameters will be assessed in order to investigate mechanisms responsible for pain relief by esketamine infusions. Furthermore, the cost-effectiveness will be analyzed. METHODS In this RCT, the primary objective is to demonstrate that an intermittent esketamine dosing regimen is non-inferior to a continuous esketamine dosing regimen at 3 months follow-up. We will include 60 adult CRPS patients. The inpatient treatment group receives a continuous intravenous esketamine infusion for 6 consecutive days. The outpatient treatment group receives a 6-hour intravenous esketamine infusion every 2 weeks for 3 months. Esketamine dose will be individually tailored and is started at 0.05 mg/kg/h and can be increased to a maximum of 0.2 mg/kg/h. Each patient will be followed for 6 months. The primary study parameter is perceived pain intensity, measured by an 11-point Numerical Rating Scale. Secondary study parameters are conditioned pain modulation, quantitative sensory testing, adverse events, thermography, blood inflammatory parameter, questionnaires about functionality, quality of life and mood and costs per patient. DISCUSSION If our study reveals non-inferiority between intermittent and continuous esketamine infusions, these findings can be beneficial to increase the availability and flexibility of esketamine infusions through outpatient treatments. Furthermore, the costs of outpatient esketamine infusions could be lower than inpatient esketamine infusions. In addition, secondary parameters may predict response to esketamine treatment. TRIAL REGISTRATION ClinicalTrials.gov Identifier NCT05212571 , date of registration 01-28-2022. PROTOCOL VERSION Version 3, February 2022.
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Affiliation(s)
- Thomas J P Mangnus
- Department of Anesthesiology, Center for Pain Medicine, Erasmus MC University Medical Center, Rotterdam, the Netherlands.
| | - Maaike Dirckx
- Department of Anesthesiology, Center for Pain Medicine, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Krishna D Bharwani
- Department of Anesthesiology, Center for Pain Medicine, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Sara J Baart
- Department of Biostatistics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Theodora A M Siepman
- Department of Anesthesiology, Center for Pain Medicine, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Ken Redekop
- Institute of Health Policy & Management, Erasmus University, Rotterdam, the Netherlands
| | - Willem A Dik
- Laboratory Medical Immunology, Department of Immunology, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Cecile C de Vos
- Department of Anesthesiology, Center for Pain Medicine, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Frank J P M Huygen
- Department of Anesthesiology, Center for Pain Medicine, Erasmus MC University Medical Center, Rotterdam, the Netherlands
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16
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Edwards RR, Schreiber KL, Dworkin RH, Turk DC, Baron R, Freeman R, Jensen TS, Latremoliere A, Markman JD, Rice ASC, Rowbotham M, Staud R, Tate S, Woolf CJ, Andrews NA, Carr DB, Colloca L, Cosma-Roman D, Cowan P, Diatchenko L, Farrar J, Gewandter JS, Gilron I, Kerns RD, Marchand S, Niebler G, Patel KV, Simon LS, Tockarshewsky T, Vanhove GF, Vardeh D, Walco GA, Wasan AD, Wesselmann U. Optimizing and Accelerating the Development of Precision Pain Treatments for Chronic Pain: IMMPACT Review and Recommendations. THE JOURNAL OF PAIN 2023; 24:204-225. [PMID: 36198371 PMCID: PMC10868532 DOI: 10.1016/j.jpain.2022.08.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 08/01/2022] [Accepted: 08/17/2022] [Indexed: 11/06/2022]
Abstract
Large variability in the individual response to even the most-efficacious pain treatments is observed clinically, which has led to calls for a more personalized, tailored approach to treating patients with pain (ie, "precision pain medicine"). Precision pain medicine, currently an aspirational goal, would consist of empirically based algorithms that determine the optimal treatments, or treatment combinations, for specific patients (ie, targeting the right treatment, in the right dose, to the right patient, at the right time). Answering this question of "what works for whom" will certainly improve the clinical care of patients with pain. It may also support the success of novel drug development in pain, making it easier to identify novel treatments that work for certain patients and more accurately identify the magnitude of the treatment effect for those subgroups. Significant preliminary work has been done in this area, and analgesic trials are beginning to utilize precision pain medicine approaches such as stratified allocation on the basis of prespecified patient phenotypes using assessment methodologies such as quantitative sensory testing. Current major challenges within the field include: 1) identifying optimal measurement approaches to assessing patient characteristics that are most robustly and consistently predictive of inter-patient variation in specific analgesic treatment outcomes, 2) designing clinical trials that can identify treatment-by-phenotype interactions, and 3) selecting the most promising therapeutics to be tested in this way. This review surveys the current state of precision pain medicine, with a focus on drug treatments (which have been most-studied in a precision pain medicine context). It further presents a set of evidence-based recommendations for accelerating the application of precision pain methods in chronic pain research. PERSPECTIVE: Given the considerable variability in treatment outcomes for chronic pain, progress in precision pain treatment is critical for the field. An array of phenotypes and mechanisms contribute to chronic pain; this review summarizes current knowledge regarding which treatments are most effective for patients with specific biopsychosocial characteristics.
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Affiliation(s)
| | | | | | - Dennis C Turk
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, Washington
| | - Ralf Baron
- Division of Neurological Pain Research and Therapy, Department of Neurology, University Hospital Schleswig-Holstein, Arnold-Heller-Straße 3, House D, 24105 Kiel, Germany
| | - Roy Freeman
- Harvard Medical School, Boston, Massachusetts
| | | | | | | | | | | | | | | | | | - Nick A Andrews
- Salk Institute for Biological Studies, San Diego, California
| | | | | | | | - Penney Cowan
- American Chronic Pain Association, Rocklin, California
| | - Luda Diatchenko
- Department of Anesthesia and Faculty of Dentistry, McGill University, Montreal, California
| | - John Farrar
- University of Pennsylvania, Philadelphia, Pennsylvania
| | | | | | - Robert D Kerns
- Yale University, Departments of Psychiatry, Neurology, and Psychology, New Haven, Connecticut
| | | | | | - Kushang V Patel
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, Washington
| | | | | | | | | | - Gary A Walco
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, Washington
| | - Ajay D Wasan
- University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Ursula Wesselmann
- Department of Anesthesiology/Division of Pain Medicine, Neurology and Psychology, The University of Alabama at Birmingham, Birmingham, Alabama
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17
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Kunkel A, Bingel U. [Placebo effects in analgesia : Influence of expectations on the efficacy and tolerability of analgesic treatment]. Schmerz 2023; 37:59-71. [PMID: 36637498 PMCID: PMC9889476 DOI: 10.1007/s00482-022-00685-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/18/2022] [Indexed: 01/14/2023]
Abstract
Expectations of patients influence the perception and neuronal processing of acute and chronic pain and modulate the effectiveness of analgesic treatment. The expectation of treatment is not only the most important determinant of placebo analgesia. Expectations of treatment also influence the efficacy and tolerability of "active" pharmacological and non-pharmacological treatment of pain. Recent insights into the psychological and neurobiological mechanisms underlying the clinically relevant effects of treatment expectations enable and call for the systematic integration and modulation of treatment expectations into analgesic treatment concepts. Such a strategy promises to optimize analgesic treatment and to prevent or reduce the burden of unwanted side effects and the misuse of analgesics, particularly of opioids. This review highlights the current concepts, recent achievements and also challenges and key open research questions.
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Affiliation(s)
- Angelika Kunkel
- Klinik für Neurologie, Zentrum für translationale Neuro- und Verhaltenswissenschaften, Universitätsklinikum Essen, Hufelandstr. 55, 45147, Essen, Deutschland.
| | - Ulrike Bingel
- Klinik für Neurologie, Zentrum für translationale Neuro- und Verhaltenswissenschaften, Universitätsklinikum Essen, Hufelandstr. 55, 45147, Essen, Deutschland
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18
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Fauchon C, Kim JA, El-Sayed R, Osborne NR, Rogachov A, Cheng JC, Hemington KS, Bosma RL, Dunkley BT, Oh J, Bhatia A, Inman RD, Davis KD. A Hidden Markov Model reveals magnetoencephalography spectral frequency-specific abnormalities of brain state power and phase-coupling in neuropathic pain. Commun Biol 2022; 5:1000. [PMID: 36131088 PMCID: PMC9492713 DOI: 10.1038/s42003-022-03967-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Accepted: 09/08/2022] [Indexed: 11/09/2022] Open
Abstract
Neuronal populations in the brain are engaged in a temporally coordinated manner at rest. Here we show that spontaneous transitions between large-scale resting-state networks are altered in chronic neuropathic pain. We applied an approach based on the Hidden Markov Model to magnetoencephalography data to describe how the brain moves from one activity state to another. This identified 12 fast transient (~80 ms) brain states including the sensorimotor, ascending nociceptive pathway, salience, visual, and default mode networks. Compared to healthy controls, we found that people with neuropathic pain exhibited abnormal alpha power in the right ascending nociceptive pathway state, but higher power and coherence in the sensorimotor network state in the beta band, and shorter time intervals between visits of the sensorimotor network, indicating more active time in this state. Conversely, the neuropathic pain group showed lower coherence and spent less time in the frontal attentional state. Therefore, this study reveals a temporal imbalance and dysregulation of spectral frequency-specific brain microstates in patients with neuropathic pain. These findings can potentially impact the development of a mechanism-based therapeutic approach by identifying brain targets to stimulate using neuromodulation to modify abnormal activity and to restore effective neuronal synchrony between brain states.
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Affiliation(s)
- Camille Fauchon
- Division of Brain, Imaging, and Behaviour, Krembil Brain Institute, University Health Network, Toronto, ON, M5T 2S8, Canada
| | - Junseok A Kim
- Division of Brain, Imaging, and Behaviour, Krembil Brain Institute, University Health Network, Toronto, ON, M5T 2S8, Canada.,Institute of Medical Science, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Rima El-Sayed
- Division of Brain, Imaging, and Behaviour, Krembil Brain Institute, University Health Network, Toronto, ON, M5T 2S8, Canada.,Institute of Medical Science, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Natalie R Osborne
- Division of Brain, Imaging, and Behaviour, Krembil Brain Institute, University Health Network, Toronto, ON, M5T 2S8, Canada.,Institute of Medical Science, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Anton Rogachov
- Division of Brain, Imaging, and Behaviour, Krembil Brain Institute, University Health Network, Toronto, ON, M5T 2S8, Canada.,Institute of Medical Science, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Joshua C Cheng
- Division of Brain, Imaging, and Behaviour, Krembil Brain Institute, University Health Network, Toronto, ON, M5T 2S8, Canada.,Institute of Medical Science, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Kasey S Hemington
- Division of Brain, Imaging, and Behaviour, Krembil Brain Institute, University Health Network, Toronto, ON, M5T 2S8, Canada.,Institute of Medical Science, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Rachael L Bosma
- Division of Brain, Imaging, and Behaviour, Krembil Brain Institute, University Health Network, Toronto, ON, M5T 2S8, Canada
| | - Benjamin T Dunkley
- Neurosciences & Mental Health Program, The Hospital for Sick Children Research Institute, Toronto, ON, M5G 0A4, Canada.,Diagnostic Imaging, The Hospital for Sick Children, Toronto, ON, M5G 0A4, Canada.,Department of Medical Imaging, University of Toronto, Toronto, ON, M5T 1W7, Canada
| | - Jiwon Oh
- Div of Neurology, Dept of Medicine, St. Michael's Hospital, Toronto, ON, M5B 1W8, Canada
| | - Anuj Bhatia
- Division of Brain, Imaging, and Behaviour, Krembil Brain Institute, University Health Network, Toronto, ON, M5T 2S8, Canada.,Department of Anesthesia and Pain Medicine, Toronto Western Hospital, and University of Toronto, Toronto, ON, M5T 2S8, Canada
| | - Robert D Inman
- Institute of Medical Science, University of Toronto, Toronto, ON, M5S 1A8, Canada.,Division of Immunology, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Karen Deborah Davis
- Division of Brain, Imaging, and Behaviour, Krembil Brain Institute, University Health Network, Toronto, ON, M5T 2S8, Canada. .,Institute of Medical Science, University of Toronto, Toronto, ON, M5S 1A8, Canada. .,Department of Surgery, University of Toronto, Toronto, ON, M5T 1P5, Canada.
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19
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Anghelescu DL, Ryan S, Wu D, Morgan KJ, Patni T, Li Y. Low-dose ketamine infusions reduce opioid use in pediatric and young adult oncology patients. Pediatr Blood Cancer 2022; 69:e29693. [PMID: 35373875 PMCID: PMC9329174 DOI: 10.1002/pbc.29693] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 03/04/2022] [Accepted: 03/07/2022] [Indexed: 11/07/2022]
Abstract
BACKGROUND Ketamine is an NMDA-receptor antagonist with analgesic and opioid-sparing properties. Although well studied in adults, more robust evidence supporting ketamine's use for pediatric pain management is needed. This retrospective study evaluates ketamine's opioid-sparing effectiveness in pediatric and young adult oncology and hematology patients. PROCEDURE Continuous ketamine infusions administered for pain management between 2010-2020 were reviewed. Data including demographic characteristics, oncology/hematology and pain diagnoses, concurrent pain medications, and ketamine infusions' dose and duration were collected. Opioid consumption data based on delivery via patient-controlled analgesia were collected 1 day before (D1), all days during (cumulatively named D2), and 1 day after (D3) ketamine infusions and calculated as morphine-equivalent doses (mg/kg/day). Data were reported for the entire study group as well as for distinct oncology and end-of-life categories, and short-term acute pain circumstances which included vaso-occlusive crises in hematology patients. Side effects were reviewed. RESULTS Significantly lower daily opioid consumption was noted in the oncology group, while decreases were not significant in the end-of-life group and in the overall study population. The acute pain group did not show an opioid reduction associated with the ketamine infusions. A largely tolerable side-effect profile was observed, with no differences among each group's incidence. CONCLUSIONS Ketamine infusions were associated with significantly reduced opioid consumption for oncology patients. The opioid-sparing effects of ketamine may vary according to clinical diagnoses and circumstances of use. Overall, low-dose ketamine infusions present an acceptable safety profile in pediatric and young adult patients; nevertheless, individual risks and benefits should be considered.
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Affiliation(s)
| | - Stephanie Ryan
- St. Jude Children's Research Hospital, Memphis, Tennessee
- Loyola University Chicago Stritch School of Medicine, Maywood, Illinois
| | - Diana Wu
- St. Jude Children's Research Hospital, Memphis, Tennessee
| | - Kyle J Morgan
- St. Jude Children's Research Hospital, Memphis, Tennessee
| | - Tushar Patni
- St. Jude Children's Research Hospital, Memphis, Tennessee
| | - Yimei Li
- St. Jude Children's Research Hospital, Memphis, Tennessee
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20
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Exploring sex differences in alpha brain activity as a potential neuromarker associated with neuropathic pain. Pain 2022; 163:1291-1302. [PMID: 34711764 DOI: 10.1097/j.pain.0000000000002491] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 09/09/2021] [Indexed: 12/31/2022]
Abstract
ABSTRACT Alpha oscillatory activity (8-13 Hz) is the dominant rhythm in the awake brain and is known to play an important role in pain states. Previous studies have identified alpha band slowing and increased power in the dynamic pain connectome (DPC) of people with chronic neuropathic pain. However, a link between alpha-band abnormalities and sex differences in brain organization in healthy individuals and those with chronic pain is not known. Here, we used resting-state magnetoencephalography to test the hypothesis that peak alpha frequency (PAF) abnormalities are general features across chronic central and peripheral conditions causing neuropathic pain but exhibit sex-specific differences in networks of the DPC (ascending nociceptive pathway [ANP], default mode network, salience network [SN], and subgenual anterior cingulate cortex). We found that neuropathic pain (N = 25 men and 25 women) was associated with increased PAF power in the DPC compared with 50 age- and sex-matched healthy controls, whereas slower PAF in nodes of the SN (temporoparietal junction) and the ANP (posterior insula) was associated with higher trait pain intensity. In the neuropathic pain group, women exhibited lower PAF power in the subgenual anterior cingulate cortex and faster PAF in the ANP and SN than men. The within-sex analyses indicated that women had neuropathic pain-related increased PAF power in the ANP, SN, and default mode network, whereas men with neuropathic pain had increased PAF power restricted to the ANP. These findings highlight neuropathic pain-related and sex-specific abnormalities in alpha oscillations across the DPC that could underlie aberrant neuronal communication in nociceptive processing and modulation.
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21
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Willis DE, Goldstein PA. Targeting Affective Mood Disorders With Ketamine to Prevent Chronic Postsurgical Pain. FRONTIERS IN PAIN RESEARCH 2022; 3:872696. [PMID: 35832728 PMCID: PMC9271565 DOI: 10.3389/fpain.2022.872696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 06/06/2022] [Indexed: 12/02/2022] Open
Abstract
The phencyclidine-derivative ketamine [2-(2-chlorophenyl)-2-(methylamino)cyclohexan-1-one] was added to the World Health Organization's Model List of Essential Medicines in 1985 and is also on the Model List of Essential Medicines for Children due to its efficacy and safety as an intravenous anesthetic. In sub-anesthetic doses, ketamine is an effective analgesic for the treatment of acute pain (such as may occur in the perioperative setting). Additionally, ketamine may have efficacy in relieving some forms of chronic pain. In 2019, Janssen Pharmaceuticals received regulatory-approval in both the United States and Europe for use of the S-enantiomer of ketamine in adults living with treatment-resistant major depressive disorder. Pre-existing anxiety/depression and the severity of postoperative pain are risk factors for development of chronic postsurgical pain. An important question is whether short-term administration of ketamine can prevent the conversion of acute postsurgical pain to chronic postsurgical pain. Here, we have reviewed ketamine's effects on the biopsychological processes underlying pain perception and affective mood disorders, focusing on non-NMDA receptor-mediated effects, with an emphasis on results from human trials where available.
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Affiliation(s)
- Dianna E. Willis
- Burke Neurological Institute, White Plains, NY, United States
- Feil Family Brain and Mind Institute, Weill Cornell Medicine, New York, NY, United States
| | - Peter A. Goldstein
- Feil Family Brain and Mind Institute, Weill Cornell Medicine, New York, NY, United States
- Department of Anesthesiology, Weill Cornell Medicine, New York, NY, United States
- Department of Medicine, Weill Cornell Medicine, New York, NY, United States
- *Correspondence: Peter A. Goldstein
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22
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Imaging as a Pain Biomarker. Neurosurg Clin N Am 2022; 33:345-350. [DOI: 10.1016/j.nec.2022.02.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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23
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Pei Y, Peng J, Zhang Y, Huang M, Zhou F. Aberrant functional connectivity and temporal variability of the dynamic pain connectome in patients with low back related leg pain. Sci Rep 2022; 12:6324. [PMID: 35428850 PMCID: PMC9012841 DOI: 10.1038/s41598-022-10238-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 03/23/2022] [Indexed: 11/17/2022] Open
Abstract
Neuroimaging studies have suggested a link between the intensity of chronic low back pain intensity and structural and functional brain alterations. However, chronic pain results from the coordination and dynamics among several brain networks that comprise the dynamic pain connectome. Here, we use resting-state functional magnetic resonance imaging and measures of static (sFC) and dynamic functional connectivity (dFC) variability in the typical (0.01–0.1 Hz) and five specific (slow-6 to slow-2) frequency bands to test hypotheses regarding disruption in this variability in low back-related leg pain (LBLP) patients who experience chronic pain and numbness. Twenty-four LBLP patients and 23 healthy controls completed clinical assessments, and partial correlational analyses between altered sFC and dFC variability and clinical measures were conducted. We found a lower within-network sFC in the ascending nociceptive pathway (Asc) and a lower cross-network sFC between nodes of the salience network and the Asc in the typical frequency band. In the slow-5 frequency band, a lower within-network sFC was found in the Asc. Abnormal cross-network sFC was found between nodes of the salience network-Asc (slow-5 and slow-6) and the default mode network-Asc (slow-4 and slow-6). Furthermore, cross-network abnormalities in the typical and certain specific frequency bands were linked to clinical assessments. These findings indicate that frequency-related within- and cross-network communication among the nodes in the dynamic pain connectome is dysfunctional in LBLP patients and that selecting specific frequencies may be potentially useful for detecting LBLP-related brain activity.
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Affiliation(s)
- Yixiu Pei
- Department of Radiology, The First Affiliated Hospital, Nanchang University, 17 Yongwaizheng Street, Nanchang, Jiangxi, 330006, People's Republic of China.,Neuroradiology Laboratory, Jiangxi Province Medical Imaging Research Institute, Nanchang, 330006, People's Republic of China.,Department of Medical Imaging, The Affiliated Ganzhou Hospital of Nanchang University, Ganzhou, Jiangxi, 341000, People's Republic of China
| | - Jidong Peng
- Department of Medical Imaging, The Affiliated Ganzhou Hospital of Nanchang University, Ganzhou, Jiangxi, 341000, People's Republic of China
| | - Yong Zhang
- Department of Pain Clinic, The First Affiliated Hospital, Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China
| | - Muhua Huang
- Department of Radiology, The First Affiliated Hospital, Nanchang University, 17 Yongwaizheng Street, Nanchang, Jiangxi, 330006, People's Republic of China.,Neuroradiology Laboratory, Jiangxi Province Medical Imaging Research Institute, Nanchang, 330006, People's Republic of China
| | - Fuqing Zhou
- Department of Radiology, The First Affiliated Hospital, Nanchang University, 17 Yongwaizheng Street, Nanchang, Jiangxi, 330006, People's Republic of China. .,Neuroradiology Laboratory, Jiangxi Province Medical Imaging Research Institute, Nanchang, 330006, People's Republic of China.
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24
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Matesanz-García L, Cuenca-Martínez F, Simón AI, Cecilia D, Goicoechea-García C, Fernández-Carnero J, Schmid AB. Signs Indicative of Central Sensitization Are Present but Not Associated with the Central Sensitization Inventory in Patients with Focal Nerve Injury. J Clin Med 2022; 11:jcm11041075. [PMID: 35207360 PMCID: PMC8876893 DOI: 10.3390/jcm11041075] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 02/04/2022] [Accepted: 02/16/2022] [Indexed: 11/16/2022] Open
Abstract
Objective: Carpal tunnel syndrome (CTS) is the most common focal nerve injury. People with CTS may show alterations in central processing of nociceptive information. It remains unclear whether the central sensitization inventory (CSI) is capable of detecting such altered central pain processing. Methods: Thirty healthy volunteers were matched with 30 people with unilateral CTS from the orthopaedic waitlist. Changes to central pain processing were established through psychophysical sensory testing (bilateral pressure pain thresholds (PPT), conditioned pain modulation, temporal summation) and pain distribution on body charts. Patients also completed pain severity and function questionnaires, psychological questionnaires and the CSI. Results: Compared to healthy volunteers, patients with CTS have lower PPTs over the carpal tunnel bilaterally (t = −4.06, p < 0.0001 ipsilateral and t = −4.58, p < 0.0001 contralateral) and reduced conditioned pain modulation efficacy (t = −7.31, p <0.0001) but no differences in temporal summation (t = 0.52, p = 0.60). The CSI was not associated with psychophysical measures or pain distributions indicative of altered central pain processing. However, there was a correlation of the CSI with the Beck Depression Inventory (r = 0.426; p = 0.019). Conclusion: Patients with CTS show signs of altered central pain mechanisms. The CSI seems unsuitable to detect changes in central pain processing but is rather associated with psychological factors in people with focal nerve injuries.
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Affiliation(s)
- Luis Matesanz-García
- Escuela Internacional de Doctorado, Department of Physical Therapy, Occupational Therapy, Rehabilitation and Physical Medicine, Rey Juan Carlos University, 28922 Alcorcón, Spain;
- Department of Physiotherap, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, 28023 Madrid, Spain
| | - Ferran Cuenca-Martínez
- Exercise Intervention for Health Research Group (EXINH-RG), Department of Physiotherapy, University of Valencia, 46010 Valencia, Spain;
| | - Ana Isabel Simón
- Unit of Elbow-Hand, Service de Traumatología, Hospital Severo Ochoa, 28911 Leganés, Spain;
| | - David Cecilia
- Unit of Elbow-Hand, Service de Traumatología, Hospital 12 de Octubre, 28048 Madrid, Spain;
- Complutense University of Madrid, 28040 Madrid, Spain
- Department of Surgery, Hospital Vithas La Milagrosa, 28010 Madrid, Spain
| | - Carlos Goicoechea-García
- Department Basic Health Sciences, Rey Juan Carlos University, 28922 Alcorcón, Spain;
- Grupo Multidisciplinar de Investigación y Tratamiento del Dolor, Grupo de Excelencia Investigadora URJC-Banco de Santander, 28922 Madrid, Spain
| | - Josué Fernández-Carnero
- Grupo Multidisciplinar de Investigación y Tratamiento del Dolor, Grupo de Excelencia Investigadora URJC-Banco de Santander, 28922 Madrid, Spain
- Department of Physical Therapy, Occupational Therapy, Rehabilitation and Physical Medicine, Rey Juan Carlos University, 28922 Alcorcón, Spain
- Correspondence: (J.F.-C.); (A.B.S.)
| | - Annina B. Schmid
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
- Correspondence: (J.F.-C.); (A.B.S.)
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25
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den Hollander M, Smeets RJEM, van Meulenbroek T, van Laake-Geelen CCM, Baadjou VA, Timmers I. Exposure in Vivo as a Treatment Approach to Target Pain-Related Fear: Theory and New Insights From Research and Clinical Practice. Phys Ther 2022; 102:6515749. [PMID: 35084025 DOI: 10.1093/ptj/pzab270] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 09/21/2021] [Accepted: 11/07/2021] [Indexed: 01/07/2023]
Abstract
UNLABELLED Pain-related fear (PRF) can be a significant factor contributing to the development and maintenance of pain-related disability in individuals with persistent pain. One treatment approach to target PRF and related avoidance behavior is exposure in vivo (EXP). EXP has a long history in the field of anxiety, a field that is constantly evolving. This Perspective outlines recent theoretical advancements and how they apply to EXP for PRF, including suggestions for how to optimize inhibitory learning during EXP; reviews mechanistic work from neuroimaging supporting the targeting of PRF in people with chronic pain; and focuses on clinical applications of EXP for PRF, as EXP is moving into new directions regarding who is receiving EXP (eg, EXP in chronic secondary pain) and how treatment is provided (EXP in primary care with a crucial role for physical therapists). Considerations are provided regarding challenges, remaining questions, and promising future perspectives. IMPACT For patients with chronic pain who have elevated pain-related fear (PRF), exposure is the treatment of choice. This Perspective highlights the inhibitory learning approach, summarizes mechanistic work from experimental psychology and neuroimaging regarding PRF in chronic pain, and describes possible clinical applications of EXP in chronic secondary pain as well as in primary care.
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Affiliation(s)
- Marlies den Hollander
- Adelante Centre of Expertise in Rehabilitation and Audiology, Maastricht, the Netherlands.,Department of Rehabilitation Medicine, Care and Public Health Research Institute, Maastricht University, Maastricht, the Netherlands
| | - Rob J E M Smeets
- Department of Rehabilitation Medicine, Care and Public Health Research Institute, Maastricht University, Maastricht, the Netherlands.,CIR Revalidatie, location Eindhoven, the Netherlands
| | - Thijs van Meulenbroek
- Adelante Centre of Expertise in Rehabilitation and Audiology, Maastricht, the Netherlands.,Department of Rehabilitation Medicine, Care and Public Health Research Institute, Maastricht University, Maastricht, the Netherlands
| | - Charlotte C M van Laake-Geelen
- Adelante Centre of Expertise in Rehabilitation and Audiology, Maastricht, the Netherlands.,Department of Rehabilitation Medicine, Care and Public Health Research Institute, Maastricht University, Maastricht, the Netherlands
| | - Vera A Baadjou
- Adelante Centre of Expertise in Rehabilitation and Audiology, Maastricht, the Netherlands.,Department of Rehabilitation Medicine, Care and Public Health Research Institute, Maastricht University, Maastricht, the Netherlands
| | - Inge Timmers
- Department of Rehabilitation Medicine, Care and Public Health Research Institute, Maastricht University, Maastricht, the Netherlands
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26
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Mangnus TJP, Bharwani KD, Stronks DL, Dirckx M, Huygen FJPM. Ketamine therapy for chronic pain in The Netherlands: a nationwide survey. Scand J Pain 2022; 22:97-105. [PMID: 34432970 DOI: 10.1515/sjpain-2021-0079] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 08/04/2021] [Indexed: 01/01/2023]
Abstract
OBJECTIVES Ketamine is used to treat chronic refractory pain. However, there are no scientific guidelines for ketamine use in the Netherlands. The aim of this survey was to provide an overview of the use of ketamine for chronic pain in the Netherlands. METHODS All pain clinics in the Netherlands were contacted. A digital survey, available from June 2019 to January 2020, was sent to 68 pain clinics. The survey was completed by one pain physician as a representative of the entire pain department. The survey included questions about ketamine treatment indications, administration, dose, duration, treatment repetition and the inpatient or outpatient setting. RESULTS The survey was completed by 51 pain clinics (75.0%). Thirty-one clinics used ketamine for chronic pain treatment. The most common indication was Complex Regional Pain Syndrome (83.9%). Pain clinics administered ketamine via intravenous infusions (96.8%), iontophoresis (61.3%), subcutaneous (3.2%) or oral administration (3.2%). Intravenous ketamine treatment was offered in an inpatient setting in 14 pain clinics, in both an inpatient and outpatient setting in 11 pain clinics and in six pain clinics in an outpatient setting. In the outpatient setting, the median starting dose was 5 mg/h (IQR=17.5-5). The median maximum dose was 27.5 mg/h (IQR=100-11.9). The median infusion duration was 6 h (IQR=8-4). In the inpatient setting, the median starting dose was 5 mg/h (IQR=5-1.5) and the median maximum dose was 25 mg/h (IQR=25-14). Patients were admitted to hospital for a median of 4 days (IQR=5-1). CONCLUSIONS The results of this Dutch nationwide survey study show that there are heterogeneous treatment protocols with different indications, treatment setting and dosing regimen for the treatment of chronic pain with ketamine. This study encourages the formulation of a broader consensus and the development of evidence based guidelines for ketamine treatment.
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Affiliation(s)
- Thomas J P Mangnus
- Department of Anesthesiology, Center for Pain Medicine, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Krishna D Bharwani
- Department of Anesthesiology, Center for Pain Medicine, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Dirk L Stronks
- Department of Anesthesiology, Center for Pain Medicine, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Maaike Dirckx
- Department of Anesthesiology, Center for Pain Medicine, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Frank J P M Huygen
- Department of Anesthesiology, Center for Pain Medicine, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands
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27
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Niu H, Li W, Wang G, Hu Q, Hao R, Li T, Zhang F, Cheng T. Performances of whole-brain dynamic and static functional connectivity fingerprinting in machine learning-based classification of major depressive disorder. Front Psychiatry 2022; 13:973921. [PMID: 35958666 PMCID: PMC9360427 DOI: 10.3389/fpsyt.2022.973921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 07/08/2022] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Alterations in static and dynamic functional connectivity during resting state have been widely reported in major depressive disorder (MDD). The objective of this study was to compare the performances of whole-brain dynamic and static functional connectivity combined with machine learning approach in differentiating MDD patients from healthy controls at the individual subject level. Given the dynamic nature of brain activity, we hypothesized that dynamic connectivity would outperform static connectivity in the classification. METHODS Seventy-one MDD patients and seventy-one well-matched healthy controls underwent resting-state functional magnetic resonance imaging scans. Whole-brain dynamic and static functional connectivity patterns were calculated and utilized as classification features. Linear kernel support vector machine was employed to design the classifier and a leave-one-out cross-validation strategy was used to assess classifier performance. RESULTS Experimental results of dynamic functional connectivity-based classification showed that MDD patients could be discriminated from healthy controls with an excellent accuracy of 100% irrespective of whether or not global signal regression (GSR) was performed (permutation test with P < 0.0002). Brain regions with the most discriminating dynamic connectivity were mainly and reliably located within the default mode network, cerebellum, and subcortical network. In contrast, the static functional connectivity-based classifiers exhibited unstable classification performances, i.e., a low accuracy of 38.0% without GSR (P = 0.9926) while a high accuracy of 96.5% with GSR (P < 0.0002); moreover, there was a considerable variability in the distribution of brain regions with static connectivity most informative for classification. CONCLUSION These findings suggest the superiority of dynamic functional connectivity in machine learning-based classification of depression, which may be helpful for a better understanding of the neural basis of MDD as well as for the development of effective computer-aided diagnosis tools in clinical settings.
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Affiliation(s)
- Heng Niu
- Department of MRI, Shanxi Cardiovascular Hospital, Taiyuan, China
| | - Weirong Li
- Department of Neurology, Shanxi Cardiovascular Hospital, Taiyuan, China
| | - Guiquan Wang
- Department of Neurology, Shanxi Cardiovascular Hospital, Taiyuan, China
| | - Qiong Hu
- Department of Neurology, Shanxi Cardiovascular Hospital, Taiyuan, China
| | - Rui Hao
- Department of Neurology, Shanxi Cardiovascular Hospital, Taiyuan, China
| | - Tianliang Li
- Department of Ultrasound, Shanxi Cardiovascular Hospital, Taiyuan, China
| | - Fan Zhang
- Department of Medical Imaging, Shanxi Traditional Chinese Medical Hospital, Taiyuan, China
| | - Tao Cheng
- Department of Neurology, Shanxi Cardiovascular Hospital, Taiyuan, China
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28
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Defrin R, Gruener H, Gaidukov E, Bondi M, Rachamim-Katz O, Ringler E, Blumen N, Zeilig G. From acute to long-term alterations in pain processing and modulation after spinal cord injury: mechanisms related to chronification of central neuropathic pain. Pain 2022; 163:e94-e105. [PMID: 33863855 DOI: 10.1097/j.pain.0000000000002315] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 04/10/2021] [Indexed: 11/26/2022]
Abstract
ABSTRACT A severe and debilitating consequence of a spinal cord injury (SCI) is central neuropathic pain (CNP). Our aim was to investigate the processes leading to CNP emergence and chronification by analyzing causal relationship over time between spinothalamic function, pain excitability, and pain inhibition after SCI. This longitudinal follow-up study included 53 patients with acute SCI and 20 healthy controls. Spinothalamic, pain excitability, and intrasegmental and extrasegmental pain inhibition indices were repeatedly evaluated at 1.5, 3, and 6 months post-SCI. Between- and within-group analyses were conducted among those patients who eventually developed CNP and those who did not. Healthy controls were evaluated twice for repeatability analysis. Patients who developed CNP, compared with those who did not, exhibited increased thermal thresholds (P < 0.05), reduced pain adaptation (P < 0.01), and conditioned pain modulation (P < 0.05), early post-injury, and the CNP group's manifestations remained worse throughout the follow-up. By contrast, allodynia frequency was initially similar across SCI groups, but gradually increased in the subacute phase onward only among the CNP group (P < 0.001), along with CNP emergence. Early worse spinothalamic and pain inhibition preceded CNP and predicted its occurrence, and early worse pain inhibition mediated the link between spinothalamic function and CNP. Crossover associations were observed between early and late pain inhibition and excitability. Inefficient intrasegmental and extrasegmental inhibition, possibly resulting from spinothalamic deafferentation, seems to ignite CNP chronification. Pain excitability probably contributes to CNP maintenance, possibly via further exhaustion of the inhibitory control. Preemptive treatment promoting antinociception early post-SCI may mitigate or prevent CNP.
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Affiliation(s)
- Ruth Defrin
- Department of Physical Therapy at Sackler Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Hila Gruener
- Department of Physical Therapy at Sackler Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Evgeni Gaidukov
- Department of Neurological Rehabilitation, Chaim Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel
- Department of Rehabilitation Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Moshe Bondi
- Department of Neurological Rehabilitation, Chaim Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel
- Department of Rehabilitation Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Orna Rachamim-Katz
- Barzilai Day Care Rehabilitation Unit, Barzilai Medical Center, Ashkelon, Israel
| | - Erez Ringler
- Department of Neurological Rehabilitation, Chaim Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel
- Department of Rehabilitation Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Nava Blumen
- Department of Neurological Rehabilitation, Chaim Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel
- Department of Rehabilitation Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Gabi Zeilig
- Department of Neurological Rehabilitation, Chaim Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel
- Department of Rehabilitation Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
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29
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Treister R, Honigman L, Berger A, Cohen B, Asaad I, Kuperman P, Tellem R, Hochberg U, Strauss I. Temporal Summation Predicts De Novo Contralateral Pain After Cordotomy in Patients With Refractory Cancer Pain. Neurosurgery 2022; 90:59-65. [PMID: 34982871 DOI: 10.1227/neu.0000000000001734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 08/06/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Percutaneous cervical cordotomy (PCC), which selectively interrupts ascending nociceptive pathways in the spinal cord, can mitigate severe refractory cancer pain. It has an impressive success rate, with most patients emerging pain-free. Aside from the usual complications of neurosurgical procedures, the risks of PCC include development of contralateral pain, which is less understood. OBJECTIVE To evaluate whether sensory and pain sensitivity, as measured by quantitative sensory testing (QST), are associated with PCC clinical outcomes. METHODS Fourteen palliative care cancer patients with severe chronic refractory pain limited mainly to one side of the body underwent comprehensive quantitative sensory testing assessment pre-PPC and post-PCC. They were also queried about maximal pain during the 24 h precordotomy (0-10 numerical pain scale). RESULTS All 14 patients reported reduced pain postcordotomy, with 7 reporting complete resolution. Four patients reported de novo contralateral pain. Reduced sensitivity in sensory and pain thresholds to heat and mechanical stimuli was recorded on the operated side (P = .028). Sensitivity to mechanical pressure increased on the unaffected side (P = .023), whereas other sensory thresholds were unchanged. The presurgical temporal summation values predicted postoperative contralateral pain (r = 0.582, P = .037). CONCLUSION The development of contralateral pain in patients postcordotomy for cancer pain might be due to central sensitization. Temporal summation could serve as a potential screening tool to identify those who are most likely at risk to develop contralateral pain. Analysis of PCC affords a unique opportunity to investigate how a specific lesion to the nociceptive system affects pain processes.
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Affiliation(s)
- Roi Treister
- Department of Nursing, Faculty of Social Welfare and Health Sciences, University of Haifa, Haifa, Israel
| | - Liat Honigman
- Department of Nursing, Faculty of Social Welfare and Health Sciences, University of Haifa, Haifa, Israel
| | - Assaf Berger
- Functional Neurosurgery Unit, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.,Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ben Cohen
- Institute of Pain Medicine, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Israa Asaad
- Department of Nursing, Faculty of Social Welfare and Health Sciences, University of Haifa, Haifa, Israel
| | - Pora Kuperman
- Department of Nursing, Faculty of Social Welfare and Health Sciences, University of Haifa, Haifa, Israel
| | - Rotem Tellem
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.,The Palliative Medicine Care Unit, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Uri Hochberg
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.,Institute of Pain Medicine, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Ido Strauss
- Department of Nursing, Faculty of Social Welfare and Health Sciences, University of Haifa, Haifa, Israel.,Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
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Abstract
Managing chronic pain remains a major unmet clinical challenge. Patients can be treated with a range of interventions, but pharmacotherapy is the most common. These include opioids, antidepressants, calcium channel modulators, sodium channel blockers, and nonsteroidal anti-inflammatory drugs. Many of these drugs target a particular mechanism; however, chronic pain in many diseases is multifactorial and induces plasticity throughout the sensory neuroaxis. Furthermore, comorbidities such as depression, anxiety, and sleep disturbances worsen quality of life. Given the complexity of mechanisms and symptoms in patients, it is unsurprising that many fail to achieve adequate pain relief from a single agent. The efforts to develop novel drug classes with better efficacy have not always proved successful; a multimodal or combination approach to analgesia is an important strategy in pain control. Many patients frequently take more than one medication, but high-quality evidence to support various combinations is often sparse. Ideally, combining drugs would produce synergistic action to maximize analgesia and reduce side effects, although sub-additive and additive analgesia is still advantageous if additive side-effects can be avoided. In this review, we discuss pain mechanisms, drug actions, and the rationale for mechanism-led treatment selection.Abbreviations: COX - cyclooxygenase, CGRP - calcitonin gene-related peptide, CPM - conditioned pain modulation, NGF - nerve growth factor, NNT - number needed to treat, NMDA - N-methyl-d-aspartate, NSAID - nonsteroidal anti-inflammatory drugs, TCA - tricyclic antidepressant, SNRI - serotonin-noradrenaline reuptake inhibitor, QST - quantitative sensory testing.
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Affiliation(s)
- Ryan Patel
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, UK
| | - Anthony H Dickenson
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, UK
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Sean M, Coulombe-Lévêque A, Bordeleau M, Vincenot M, Gendron L, Marchand S, Léonard G. Comparison of Thermal and Electrical Modalities in the Assessment of Temporal Summation of Pain and Conditioned Pain Modulation. FRONTIERS IN PAIN RESEARCH 2021; 2:659563. [PMID: 35295416 PMCID: PMC8915752 DOI: 10.3389/fpain.2021.659563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 08/16/2021] [Indexed: 11/29/2022] Open
Abstract
Temporal summation of pain (TSP) and conditioned pain modulation (CPM) can be measured using a thermode and a cold pressor test (CPT). Unfortunately, these tools are complex, expensive, and are ill-suited for routine clinical assessments. Building on the results from an exploratory study that attempted to use transcutaneous electrical nerve stimulation (TENS) to measure CPM and TSP, the present study assesses whether a “new” TENS protocol can be used instead of the thermode and CPT to measure CPM and TSP. The objective of this study was to compare the thermode/CPT protocol with the new TENS protocol, by (1) measuring the association between the TSP evoked by the two protocols; (2) measuring the association between the CPM evoked by the two protocols; and by (3) assessing whether the two protocols successfully trigger TSP and CPM in a similar number of participants. We assessed TSP and CPM in 50 healthy participants, using our new TENS protocol and a thermode/CPT protocol (repeated measures and randomized order). In the TENS protocol, both the test stimulus (TS) and the conditioning stimulus (CS) were delivered using TENS; in the thermode/CPT protocol, the TS was delivered using a thermode and the CS consisted of a CPT. There was no association between the response evoked by the two protocols, neither for TSP nor for CPM. The number of participants showing TSP [49 with TENS and 29 with thermode (p < 0.001)] and CPM [16 with TENS and 30 with thermode (p = 0.01)] was different in both protocols. Our results suggest that response to one modality does not predict response to the other; as such, TENS cannot be used instead of a thermode/CPT protocol to assess TSP and CPM without significantly affecting the results. Moreover, while at first glance it appears that TENS is more effective than the thermode/CPT protocol to induce TSP, but less so to induce CPM, these results should be interpreted carefully. Indeed, TSP and CPM response appear to be modality-dependent as opposed to an absolute phenomenon, and the two protocols may tap into entirely different mechanisms, especially in the case of TSP.
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Affiliation(s)
- Monica Sean
- Research Centre on Aging, School of Rehabilitation, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Alexia Coulombe-Lévêque
- Research Centre on Aging, School of Rehabilitation, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Martine Bordeleau
- Research Centre on Aging, School of Rehabilitation, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Matthieu Vincenot
- Research Centre on Aging, School of Rehabilitation, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Louis Gendron
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Serge Marchand
- Department of Neurosurgery, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Guillaume Léonard
- Research Centre on Aging, School of Rehabilitation, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
- *Correspondence: Guillaume Léonard
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Himmelseher S, Kochs EF. Ready for a "breakthrough" with ketamine? A look at recent pharmacological insights! Curr Opin Anaesthesiol 2021; 34:393-401. [PMID: 34052823 DOI: 10.1097/aco.0000000000001017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
PURPOSE OF REVIEW To update pharmacological insights on ketamine integrating information from different disciplines for developing steps to "breakthrough" approaches in clinical challenges. RECENT FINDINGS Pharmacokinetic/pharmacodynamic (PK/PD) models have incorporated recirculation, ketamine metabolites, drug-drug interaction, and covariates such as age. Ketamine-induced relief from treatment-resistant depression has been explained by "disinhibition" of gamma-aminobutyric acid-ergic interneurons and synaptogenic mechanisms requiring neurotrophic signals. Neuroimaging/electroencephalographic investigations have shown an increase in gamma spectral power in healthy volunteers and patients with depression, but also opposite changes in functional network connectivity after subanesthetic ketamine. Volunteer data may not be transferable to clinical conditions. Altered states of consciousness induced by subanesthetic ketamine have been described by disruption of resisting-state functional networks and frontoparietal connectivity with preservation of multisensory and sensor-motor networks. This has been interpreted as a "disconnected consciousness". SUMMARY More precise PK/PD models may improve the ketamine use regimen. The findings from research on depression are an important discovery because ketamine's impact on neuronal plasticity and synaptogenesis in human brain disease has directly been documented. Psychic adverse effects with subanesthetic ketamine are related to a "disconnected consciousness". Overall, progress has been made, but the "breakthrough" still has to come.
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Affiliation(s)
- Sabine Himmelseher
- Klinik für Anästhesiologie und Intensivmedizin, Technische Universität München, Klinikum rechts der Isar, Munich, Germany
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Mills EP, Keay KA, Henderson LA. Brainstem Pain-Modulation Circuitry and Its Plasticity in Neuropathic Pain: Insights From Human Brain Imaging Investigations. FRONTIERS IN PAIN RESEARCH 2021; 2:705345. [PMID: 35295481 PMCID: PMC8915745 DOI: 10.3389/fpain.2021.705345] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 06/23/2021] [Indexed: 11/17/2022] Open
Abstract
Acute pain serves as a protective mechanism that alerts us to potential tissue damage and drives a behavioural response that removes us from danger. The neural circuitry critical for mounting this behavioural response is situated within the brainstem and is also crucial for producing analgesic and hyperalgesic responses. In particular, the periaqueductal grey, rostral ventromedial medulla, locus coeruleus and subnucleus reticularis dorsalis are important structures that directly or indirectly modulate nociceptive transmission at the primary nociceptive synapse. Substantial evidence from experimental animal studies suggests that plasticity within this system contributes to the initiation and/or maintenance of chronic neuropathic pain, and may even predispose individuals to developing chronic pain. Indeed, overwhelming evidence indicates that plasticity within this circuitry favours pro-nociception at the primary synapse in neuropathic pain conditions, a process that ultimately contributes to a hyperalgesic state. Although experimental animal investigations have been crucial in our understanding of the anatomy and function of the brainstem pain-modulation circuitry, it is vital to understand this system in acute and chronic pain states in humans so that more effective treatments can be developed. Recent functional MRI studies have identified a key role of this system during various analgesic and hyperalgesic responses including placebo analgesia, offset analgesia, attentional analgesia, conditioned pain modulation, central sensitisation and temporal summation. Moreover, recent MRI investigations have begun to explore brainstem pain-modulation circuitry plasticity in chronic neuropathic pain conditions and have identified altered grey matter volumes and functioning throughout the circuitry. Considering the findings from animal investigations, it is likely that these changes reflect a shift towards pro-nociception that ultimately contributes to the maintenance of neuropathic pain. The purpose of this review is to provide an overview of the human brain imaging investigations that have improved our understanding of the pain-modulation system in acute pain states and in neuropathic conditions. Our interpretation of the findings from these studies is often guided by the existing body of experimental animal literature, in addition to evidence from psychophysical investigations. Overall, understanding the plasticity of this system in human neuropathic pain conditions alongside the existing experimental animal literature will ultimately improve treatment options.
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Abstract
PURPOSE OF REVIEW Neuropathic pain remains difficult to treat. This review provides an update regarding recent advances in therapeutic management, particularly with regards to newer drugs, neurostimulation techniques and original study designs. RECENT FINDINGS Although the mainstay of neuropathic pain management is still represented by drug therapy, particularly antidepressants and antiepileptics, the place of nonpharmacological therapy including in particular brain neuromodulation techniques has substantially increased in recent years. Newer study designs are also increasingly implemented, based on in depth phenotypic profiling to achieve more individualized therapy, or on screening strategies to decrease placebo effect and contribute to increase assay sensitivity. These approaches are now considered the most promising to decrease therapeutic failures in neuropathic pain. SUMMARY Neuropathic pain management should not be restricted to pharmacotherapy but now encompasses multiple approaches including particularly neuromodulation techniques. Multimodal assessment can also help identify predictors of the response in clinical trials in order to ensure appropriate management.
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Osborne NR, Anastakis DJ, Kim JA, El-Sayed R, Cheng JC, Rogachov A, Hemington KS, Bosma RL, Fauchon C, Davis KD. Sex-Specific Abnormalities and Treatment-Related Plasticity of Subgenual Anterior Cingulate Cortex Functional Connectivity in Chronic Pain. FRONTIERS IN PAIN RESEARCH 2021; 2:673538. [PMID: 35295450 PMCID: PMC8915549 DOI: 10.3389/fpain.2021.673538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 04/28/2021] [Indexed: 11/17/2022] Open
Abstract
The subgenual anterior cingulate cortex (sgACC) is a key node of the descending antinociceptive system with sex differences in its functional connectivity (FC). We previously reported that, in a male-prevalent chronic pain condition, sgACC FC is abnormal in women but not in men. This raises the possibility that, within a sex, sgACC FC may be either protective or represent a vulnerability to develop a sex-dominant chronic pain condition. The aim of this study was to characterize sgACC FC in a female-dominant chronic pain condition, carpal tunnel syndrome (CTS), to investigate whether sgACC abnormalities are a common feature in women with chronic pain or unique to individuals with pain conditions that are more prevalent in the opposite sex. We used fMRI to determine the resting state FC of the sgACC in healthy controls (HCs, n = 25, 18 women; 7 men) and people with CTS before (n = 25, 18 women; 7 men) and after (n = 17, 13 women; 4 men) successful surgical treatment. We found reduced sgACC FC with the medial pre-frontal cortex (mPFC) and temporal lobe in CTS compared with HCs. The group-level sgACC-mPFC FC abnormality was driven by men with CTS, while women with CTS did not have sgACC FC abnormalities compared with healthy women. We also found that age and sex influenced sgACC FC in both CTS and HCs, with women showing greater FC with bilateral frontal poles and men showing greater FC with the parietal operculum. After surgery, there was reduced sgACC FC with the orbitofrontal cortex, striatum, and premotor areas and increased FC with the posterior insula and precuneus compared with pre-op scans. Abnormally reduced sgACC-mPFC FC in men but not women with a female-prevalent chronic pain condition suggests pain-related sgACC abnormalities may not be specific to women but rather to individuals who develop chronic pain conditions that are more dominant in the opposite sex. Our data suggest the sgACC plays a role in chronic pain in a sex-specific manner, and its communication with other regions of the dynamic pain connectome undergoes plasticity following pain-relieving treatment, supporting it as a potential therapeutic target for neuromodulation in chronic pain.
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Affiliation(s)
- Natalie R. Osborne
- Krembil Research Institute, Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Dimitri J. Anastakis
- Krembil Research Institute, Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
- Toronto Western Hospital, University Health Network, Toronto, ON, Canada
- Department of Surgery, University of Toronto, Toronto, ON, Canada
| | - Junseok Andrew Kim
- Krembil Research Institute, Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Rima El-Sayed
- Krembil Research Institute, Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Joshua C. Cheng
- Krembil Research Institute, Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Anton Rogachov
- Krembil Research Institute, Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Kasey S. Hemington
- Krembil Research Institute, Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Rachael L. Bosma
- Krembil Research Institute, Krembil Brain Institute, University Health Network, Toronto, ON, Canada
| | - Camille Fauchon
- Krembil Research Institute, Krembil Brain Institute, University Health Network, Toronto, ON, Canada
| | - Karen D. Davis
- Krembil Research Institute, Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
- Toronto Western Hospital, University Health Network, Toronto, ON, Canada
- Department of Surgery, University of Toronto, Toronto, ON, Canada
- *Correspondence: Karen D. Davis
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Mangnus TJP, Dirckx M, Bharwani KD, de Vos CC, Frankema SPG, Stronks DL, Huygen FJPM. Effect of intravenous low-dose S-ketamine on pain in patients with Complex Regional Pain Syndrome: A retrospective cohort study. Pain Pract 2021; 21:890-897. [PMID: 34233070 PMCID: PMC9291497 DOI: 10.1111/papr.13056] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 06/14/2021] [Accepted: 06/30/2021] [Indexed: 12/21/2022]
Abstract
Objective The objective of this study was to assess the effectiveness of a low‐dose intravenous S‐ketamine treatment on refractory pain in patients with Complex Regional Pain Syndrome (CRPS). Methods In this retrospective study, patients with CRPS who received intravenous S‐ketamine from March 2010 to April 2019 were included. According to our inpatient protocol, S‐ketamine dose was increased until pain reduction was achieved or side effects were observed. Maximum dose was 14 mg/h and treatment duration was 7 days. Primary outcome parameters were pain scores (Numeric Rating Scale) at baseline (T0), end of infusion (T1), and approximately 4 weeks postinfusion (T2). Patients were categorized as responder/nonresponder at T1 and T2. Patients were considered a responder in case there was pain score reduction of greater than or equal to 2 points or if treatment was reported as successful. Results Forty‐eight patients were included. Mean disease duration was 5 years (interquartile range [IQR] = 6 years). Median pain score significantly decreased from 8 (IQR = 2) at T0 to 6 (IQR = 4) at T1 (p < 0.001). At T1, 62% of the patients were responders. At T2, 48% of the patients remained a responder. A significant proportion of the responders at T1 turned into nonresponders at T2 (p = 0.03). Conclusion In a group of patients with CRPS with refractory pain, low‐dose intravenous S‐ketamine treatment resulted in effective pain relief during infusion. Although a significant proportion of initial responders became nonresponders at follow‐up, half of the patients were still a responder at ~ 4 weeks postinfusion. Further research is needed to investigate mechanisms responsible for pain relief by S‐ketamine infusions and to ascertain possible predictors of response to the treatment.
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Affiliation(s)
- Thomas J P Mangnus
- Center for Pain Medicine, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Maaike Dirckx
- Center for Pain Medicine, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Krishna D Bharwani
- Center for Pain Medicine, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Cecile C de Vos
- Center for Pain Medicine, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Sander P G Frankema
- Center for Pain Medicine, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Dirk L Stronks
- Center for Pain Medicine, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Frank J P M Huygen
- Center for Pain Medicine, Erasmus MC University Medical Center, Rotterdam, The Netherlands
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Paredes AC, Pinto JM, Almeida A, Pinto PR. Predictive value of quantitative sensory testing for acute and chronic postsurgical pain after total joint arthroplasty: a systematic review. Pain 2021; 163:e385-e400. [PMID: 34224493 DOI: 10.1097/j.pain.0000000000002385] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 06/14/2021] [Indexed: 11/25/2022]
Abstract
ABSTRACT Quantitative sensory testing (QST) can be useful to identify high-risk patients for the development of chronic postsurgical pain. This systematic review aims to assess if presurgical sensory sensitivity measured using QST is associated with acute and chronic postsurgical pain after total joint arthroplasty. A systematic search was performed in September 2020 in PubMed, EMBASE, Web of Science, and Scopus, using terms related to total joint arthroplasty and QST. Prospective studies were included if they reported an association between presurgical QST and postsurgical pain in adults with osteoarthritis undergoing primary unilateral total joint arthroplasty. From 2994 identified studies, 18 met the inclusion criteria (1869 patients). Total knee arthroplasty was the most common surgery (16 studies), and pressure pain threshold was the most common test (11 studies), followed by dynamic measures (9 studies). Postsurgical pain was assessed at acute (5 studies), subacute (2 studies), and chronic (13 studies) time points. Risk of bias was assessed using the Quality in Prognosis Studies tool and evaluated as low to moderate in most domains. Fourteen studies reported at least one statistically significant association between QST and pain (acute: 4 studies, subacute: 1 study, and chronic: 9 studies). Pressure pain threshold was associated with postsurgical pain in 6 studies (of 11, 55%), heat pain threshold in 2 studies (of 6, 33%), conditioned pain modulation in 1 study (of 6, 17%), and temporal summation of pain in 5 studies (of 8, 63%). The predictive role of presurgical QST for postarthroplasty pain remains unclear, mainly because of heterogeneous methodologies and inconsistent results.
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Affiliation(s)
- Ana Cristina Paredes
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal
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Timmers I, van de Ven VG, Vlaeyen JW, Smeets RJ, Verbunt JA, de Jong JR, Kaas AL. Corticolimbic Circuitry in Chronic Pain Tracks Pain Intensity Relief Following Exposure In Vivo. BIOLOGICAL PSYCHIATRY GLOBAL OPEN SCIENCE 2021; 1:28-36. [PMID: 36324433 PMCID: PMC9616294 DOI: 10.1016/j.bpsgos.2021.03.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 03/24/2021] [Accepted: 03/24/2021] [Indexed: 12/28/2022] Open
Abstract
Background A subset of patients with chronic pain who receive exposure in vivo (EXP) treatment experience clinically relevant relief of pain intensity. Although pain relief is not an explicit therapeutic target, it is important to understand how and why this concomitant effect occurs in some patients but not others. This longitudinal study therefore aimed to characterize brain plasticity as well as to explore pretreatment factors related to pain relief. Methods Resting-state functional magnetic resonance imaging data were acquired in 30 patients with chronic pain. Twenty-three patients completed EXP, and 6-month follow-up data were available in 20 patients (magnetic resonance imaging data in 17 patients). Pain-free control data were acquired at two time points (n = 29, n = 21). Seed-based resting-state functional connectivity (rsFC) analyses were performed, with seeds in the amygdala, hippocampus, and nucleus accumbens. Results Pain relief after EXP was highly variable, with 60% of patients reporting a clinically relevant improvement. Amygdala rsFC with the middle frontal gyrus decreased significantly over time in patients but was not associated with pain relief. In contrast, greater pain relief was associated with greater decreases over time in hippocampus rsFC with the precuneus, which was related to reductions in catastrophizing (EXP therapeutic target) as well. Greater pain relief was also associated with lower pretreatment rsFC between nucleus accumbens and postcentral gyrus. Conclusions While changes in hippocampus rsFC were associated with pain relief after EXP, pretreatment nucleus accumbens rsFC showed potential prognostic value. Our findings further support the importance of corticolimbic circuitry in chronic pain, emphasizing its relation to pain relief and identifying potential underlying mechanisms and prognostic factors, warranting further testing in independent samples.
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Sex differences in brain modular organization in chronic pain. Pain 2021; 162:1188-1200. [PMID: 33044396 DOI: 10.1097/j.pain.0000000000002104] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 10/01/2020] [Indexed: 11/26/2022]
Abstract
ABSTRACT Men and women can exhibit different pain sensitivities, and many chronic pain conditions are more prevalent in one sex. Although there is evidence of sex differences in the brain, it is not known whether there are sex differences in the organization of large-scale functional brain networks in chronic pain. Here, we used graph theory with modular analysis and machine-learning of resting-state-functional magnetic resonance imaging data from 220 participants: 155 healthy controls and 65 individuals with chronic low back pain due to ankylosing spondylitis, a form of arthritis. We found an extensive overlap in the graph partitions with the major brain intrinsic systems (ie, default mode, central, visual, and sensorimotor modules), but also sex-specific network topological characteristics in healthy people and those with chronic pain. People with chronic pain exhibited higher cross-network connectivity, and sex-specific nodal graph properties changes (ie, hub disruption), some of which were associated with the severity of the chronic pain condition. Females exhibited atypically higher functional segregation in the mid cingulate cortex and subgenual anterior cingulate cortex and lower connectivity in the network with the default mode and frontoparietal modules, whereas males exhibited stronger connectivity with the sensorimotor module. Classification models on nodal graph metrics could classify an individual's sex and whether they have chronic pain with high accuracies (77%-92%). These findings highlight the organizational abnormalities of resting-state-brain networks in people with chronic pain and provide a framework to consider sex-specific pain therapeutics.
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40
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Abnormal subgenual anterior cingulate circuitry is unique to women but not men with chronic pain. Pain 2021; 162:97-108. [PMID: 32773597 DOI: 10.1097/j.pain.0000000000002016] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The subgenual anterior cingulate cortex (sgACC) plays an important role in pain modulation. We previously demonstrated sex differences in sgACC functional connectivity (FC) in healthy individuals. Given that many chronic pain conditions show sex differences in prevalence, here we tested the hypothesis that people with chronic pain exhibit a sex-specific pattern of abnormal sgACC FC. We acquired resting-state functional magnetic resonance imaging data from 156 (82 W: 74 M) healthy participants and 38 (19 W: 19 M) people with chronic low back pain resulting from ankylosing spondylitis, a condition that predominantly affects men. We confirmed that there are sex differences in sgACC FC in our large cohort of healthy adults; women had greater sgACC FC with the precuneus, a key node of the default mode network, and men had greater sgACC FC with the posterior insula and the operculum. Next, we identified an interaction effect between sex and pain status (healthy/chronic pain) for sgACC FC. Within the chronic pain group, women had greater sgACC FC than men to the default mode and sensorimotor networks. Compared to healthy women, women with chronic pain also had greater sgACC FC to the precuneus and lower FC to the hippocampus and frontal regions. No differences in sgACC FC were seen in men with vs without chronic pain. Our findings indicate that abnormal sgACC circuitry is unique to women but not men with ankylosing spondylitis-related chronic pain. These sex differences may impact the benefit of therapeutics that target the sgACC for chronic pain.
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Zhu J, Li Y, Fang Q, Shen Y, Qian Y, Cai H, Yu Y. Dynamic functional connectome predicts individual working memory performance across diagnostic categories. NEUROIMAGE-CLINICAL 2021; 30:102593. [PMID: 33647810 PMCID: PMC7930367 DOI: 10.1016/j.nicl.2021.102593] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 02/02/2021] [Accepted: 02/05/2021] [Indexed: 11/23/2022]
Abstract
We created transdiagnostic predictive working memory models using connectome-based predictive modeling (CPM). Dynamic functional connectivity-based CPM models successfully predicted working memory. Static functional connectivity-based CPM models fell short in prediction. Frontoparietal, somato-motor, default mode and visual networks contributed most to prediction.
Working memory impairment is a common feature of psychiatric disorders. Although its neural mechanisms have been extensively examined in healthy subjects or individuals with a certain clinical condition, studies investigating neural predictors of working memory in a transdiagnostic sample are scarce. The objective of this study was to create a transdiagnostic predictive working memory model from whole-brain functional connectivity using connectome-based predictive modeling (CPM), a recently developed machine learning approach. Resting-state functional MRI data from 242 subjects across 4 diagnostic categories (healthy controls and individuals with schizophrenia, bipolar disorder, and attention deficit/hyperactivity) were used to construct dynamic and static functional connectomes. Spatial working memory was assessed by the spatial capacity task. CPM was conducted to predict individual working memory from dynamic and static functional connectivity patterns. Results showed that dynamic connectivity-based CPM models successfully predicted overall working memory capacity and accuracy as well as mean reaction time, yet their static counterparts fell short in the prediction. At the neural level, we found that dynamic connectivity of the frontoparietal and somato-motor networks were negatively correlated with working memory capacity and accuracy, and those of the default mode and visual networks were positively associated with mean reaction time. Moreover, different feature selection thresholds, parcellation strategies and model validation methods as well as diagnostic categories did not significantly influence the prediction results. Our findings not only are coherent with prior reports that dynamic functional connectivity encodes more behavioral information than static connectivity, but also help advance the translation of cognitive “connectome fingerprinting” into real-world application.
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Affiliation(s)
- Jiajia Zhu
- Department of Radiology, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, China
| | - Yating Li
- Department of Radiology, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, China
| | - Qian Fang
- Department of Radiology, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, China
| | - Yuhao Shen
- Department of Radiology, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, China
| | - Yinfeng Qian
- Department of Radiology, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, China
| | - Huanhuan Cai
- Department of Radiology, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, China
| | - Yongqiang Yu
- Department of Radiology, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, China.
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Vincenot M, Coulombe-Lévêque A, Sean M, Camirand Lemyre F, Gendron L, Marchand S, Léonard G. Development and Validation of a Predictive Model of Pain Modulation Profile to Guide Chronic Pain Treatment: A Study Protocol. FRONTIERS IN PAIN RESEARCH 2021; 2:606422. [PMID: 35295452 PMCID: PMC8915565 DOI: 10.3389/fpain.2021.606422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 01/13/2021] [Indexed: 11/27/2022] Open
Abstract
Introduction: Quantitative sensory testing is frequently used in research to assess endogenous pain modulation mechanisms, such as Temporal Summation (TS) and Conditioned Pain Modulation (CPM), reflecting excitatory and inhibitory mechanisms, respectively. Numerous studies found that a dysregulation of these mechanisms is associated with chronic pain conditions. In turn, such a patient's “profile” (increased TS and/or weakened CPM) could be used to recommend different pharmacological treatments. However, the procedure to evaluate these mechanisms is time-consuming and requires expensive equipment that is not available in the clinical setting. In this study, we aim to identify psychological, physiological and socio-demographic markers that could serve as proxies to allow healthcare professionals to identify these pain phenotypes in clinic, and consequently optimize pharmacological treatments. Method: We aim to recruit a healthy participant cohort (n = 360) and a chronic pain patient cohort (n = 108). Independent variables will include psychological questionnaires, pain measurements, physiological measures and sociodemographic characteristics. Dependent variables will include TS and CPM, which will be measured using quantitative sensory testing in a single session. We will evaluate one prediction model and two validation models (for healthy and chronic pain participants) using multiple regression analysis between TS/CPM and our independent variables. The significance thresholds will be set at p = 0.05, respectively. Perspectives: This study will allow us to develop a predictive model to compute the pain modulation profile of individual patients based on their biopsychosocial characteristics. The development of the predictive model is the first step toward the overarching goal of providing clinicians with a set of quick and cheap tests, easily applicable in clinical practice to orient pharmacological treatments.
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Affiliation(s)
- Matthieu Vincenot
- Research Center on Aging, Université de Sherbrooke, Sherbrooke, QC, Canada
- Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Alexia Coulombe-Lévêque
- Research Center on Aging, Université de Sherbrooke, Sherbrooke, QC, Canada
- Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Monica Sean
- Research Center on Aging, Université de Sherbrooke, Sherbrooke, QC, Canada
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Félix Camirand Lemyre
- Centre de Recherche du Centre Hospitaliser Universitaire de Sherbrooke, Sherbrooke, QC, Canada
- Département de Mathématiques, Faculté des Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Louis Gendron
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
- Centre de Recherche du Centre Hospitaliser Universitaire de Sherbrooke, Sherbrooke, QC, Canada
| | - Serge Marchand
- Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Guillaume Léonard
- Research Center on Aging, Université de Sherbrooke, Sherbrooke, QC, Canada
- Faculty of Medicine and Health Sciences, School of Rehabilitation, Université de Sherbrooke, Sherbrooke, QC, Canada
- *Correspondence: Guillaume Léonard
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Sondermann W, Reinboldt-Jockenhöfer F, Dissemond J, Pfaar O, Bingel U, Schedlowski M. Effects of Patients' Expectation in Dermatology: Evidence from Experimental and Clinical Placebo Studies and Implications for Dermatologic Practice and Research. Dermatology 2021; 237:857-871. [PMID: 33498052 DOI: 10.1159/000513445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 11/28/2020] [Indexed: 11/19/2022] Open
Abstract
Patients' expectations towards the benefit of a treatment are key determinants of placebo responses and can affect the development and course of medical conditions and the efficacy and tolerability of active medical treatment. The mechanisms mediating these placebo and nocebo effects have been best described in the field of experimental pain and placebo analgesia. However, also in dermatology experimental and clinical studies demonstrate that various skin diseases such as inflammatory dermatoses and allergic reactions can be modulated by patients' expectations. Dermatologists should consider the important modulatory role of patients' expectations on the efficacy and tolerability of specific treatments and the key role of verbal information, patients' prior treatment experiences (associative learning), and the quality and quantity of doctor-patient communication in shaping treatment expectation. As a consequence, techniques aiming at maximizing patients' expectation effects should be implemented into daily clinical routine. By contrast, in clinical studies expectation effects should be maximally controlled and harmonized to improve the "assay sensitivity" to detect new compounds. Further translational studies, also in dermatoses that have not been investigated yet, are needed to better characterize the mechanisms underlying patients' expectation and to gain further insights into potential clinical implications of these effects in dermatologic conditions. Therefore, in this review, we provide a brief overview on the concept of expectation effects on treatment outcome in general, summarize what is already known about this topic for dermatologic diseases, and finally present the relevance of this topic in clinical dermatology.
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Affiliation(s)
- Wiebke Sondermann
- Department of Dermatology, Venereology, and Allergology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany,
| | - Finja Reinboldt-Jockenhöfer
- Department of Dermatology, Venereology, and Allergology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Joachim Dissemond
- Department of Dermatology, Venereology, and Allergology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Oliver Pfaar
- Section of Rhinology and Allergy, Department of Otorhinolaryngology, Head and Neck Surgery, University Hospital Marburg, Philipps University Marburg, Marburg, Germany
| | - Ulrike Bingel
- Department of Neurology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Manfred Schedlowski
- Institute of Medical Psychology and Behavioral Immunobiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.,Department of Clinical Neuroscience, Osher Center for Integrative Medicine, Karolinska Institutet, Stockholm, Sweden
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Abstract
BACKGROUND Ketamine is a dissociative anesthetic with analgesic properties. Ketamine's analgesic properties have been suggested to result from its dissociative properties. To the authors' knowledge, this postulate is unsubstantiated. The authors hypothesize that the dissociative and analgesic properties of ketamine are independent. METHODS The authors conducted a single-site, open-label study of ketamine anesthesia (2 mg/kg) in 15 healthy subjects. Midazolam was administered at a prespecified time point to attenuate dissociation. The authors longitudinally assessed precalibrated cuff pain intensity and quality using Patient-Reported Outcomes Measurement Information System questionnaires, and dissociation, using the Clinician Administered Dissociative States Scale. Mixed effects models were used to assess whether dissociation accounted for the effect of ketamine on pain intensity and quality. RESULTS The dissociation model demonstrated an inverted U-shaped quadratic relationship between time and dissociation scores. Additive to this effect, midazolam reduced the dissociation adjusted means by 10.3 points (95% CI, 3.4 to 17.1; P = 0.005). The pain intensity model also demonstrated a U-shaped quadratic relationship between time and pain intensity. When the pain intensity model was reanalyzed with dissociation scores as an additional covariate, the dissociation term was not retained in the model, and the other effects were preserved in direction and strength. This result was conserved for nociceptive and neuropathic pain quality. CONCLUSIONS Ketamine's analgesic properties are not exclusively caused by dissociation. Thus, ketamine may be used as a probe to advance our knowledge of dissociation independent neural circuits that encode pain. EDITOR’S PERSPECTIVE
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Tu Y, Cao J, Bi Y, Hu L. Magnetic resonance imaging for chronic pain: diagnosis, manipulation, and biomarkers. SCIENCE CHINA-LIFE SCIENCES 2020; 64:879-896. [PMID: 33247802 DOI: 10.1007/s11427-020-1822-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 09/15/2020] [Indexed: 12/16/2022]
Abstract
Pain is a multidimensional subjective experience with biological, psychological, and social factors. Whereas acute pain can be a warning signal for the body to avoid excessive injury, long-term and ongoing pain may be developed as chronic pain. There are more than 100 million people in China living with chronic pain, which has raised a huge socioeconomic burden. Studying the mechanisms of pain and developing effective analgesia approaches are important for basic and clinical research. Recently, with the development of brain imaging and data analytical approaches, the neural mechanisms of chronic pain have been widely studied. In the first part of this review, we briefly introduced the magnetic resonance imaging and conventional analytical approaches for brain imaging data. Then, we reviewed brain alterations caused by several chronic pain disorders, including localized and widespread primary pain, primary headaches and orofacial pain, musculoskeletal pain, and neuropathic pain, and present meta-analytical results to show brain regions associated with the pathophysiology of chronic pain. Next, we reviewed brain changes induced by pain interventions, such as pharmacotherapy, neuromodulation, and acupuncture. Lastly, we reviewed emerging studies that combined advanced machine learning and neuroimaging techniques to identify diagnostic, prognostic, and predictive biomarkers in chronic pain patients.
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Affiliation(s)
- Yiheng Tu
- CAS Key Laboratory of Mental Health, Institute of Psychology, Beijing, 100101, China.,Department of Psychology, University of Chinese Academy of Sciences, Beijing, 100101, China
| | - Jin Cao
- Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, 02129, USA
| | - Yanzhi Bi
- CAS Key Laboratory of Mental Health, Institute of Psychology, Beijing, 100101, China.,Department of Psychology, University of Chinese Academy of Sciences, Beijing, 100101, China
| | - Li Hu
- CAS Key Laboratory of Mental Health, Institute of Psychology, Beijing, 100101, China. .,Department of Psychology, University of Chinese Academy of Sciences, Beijing, 100101, China. .,Department of Pain Management, The State Key Clinical Specialty in Pain Medicine, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, 510260, China.
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Koulouris AE, Edwards RR, Dorado K, Schreiber KL, Lazaridou A, Rajan S, White J, Garcia J, Gibbons C, Freeman R. Reliability and Validity of the Boston Bedside Quantitative Sensory Testing Battery for Neuropathic Pain. PAIN MEDICINE (MALDEN, MASS.) 2020; 21:2336-2347. [PMID: 32895703 PMCID: PMC7593797 DOI: 10.1093/pm/pnaa192] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE Recent studies suggest that sensory phenotyping may provide critical information for the diagnosis and management of patients with chronic neuropathic pain (NP). However, many formal quantitative sensory testing (QST) paradigms require expensive equipment, a dedicated location, and substantial time commitments on the part of patient and examiner, highlighting the need for a convenient and portable "bedside" QST battery. We developed and tested a bedside QST battery in a sample of patients with chronic NP. METHODS Participants (N = 51) attended two in-person visits over approximately two weeks, during which they underwent QST using both laboratory-based equipment and simple, easily accessible bedside tools. Participants also completed questionnaires about their daily pain and NP symptoms. RESULTS Test-retest reliability estimates were highly statistically significant and did not differ between bedside (mean r = 0.60) and laboratory-based (mean r = 0.72) QST. Bedside QST variables and corresponding laboratory-based QST variables were highly correlated, suggesting adequate criterion validity for the bedside tests. CONCLUSIONS Results from the present study may have important implications for the sensory phenotyping and subsequent management of patients with chronic NP. Implementation of a protocol that uses inexpensive, portable, and convenient tools may allow for the application of QST in variety of clinical settings and advance NP research.
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Affiliation(s)
- Alexandra E Koulouris
- Department of Anesthesiology, Harvard Medical School, Brigham & Women’s Hospital, Boston, Massachusetts
| | - Robert R Edwards
- Department of Anesthesiology, Harvard Medical School, Brigham & Women’s Hospital, Boston, Massachusetts
| | - Kathleen Dorado
- Department of Anesthesiology, Harvard Medical School, Brigham & Women’s Hospital, Boston, Massachusetts
| | - Kristin L Schreiber
- Department of Anesthesiology, Harvard Medical School, Brigham & Women’s Hospital, Boston, Massachusetts
| | - Asimina Lazaridou
- Department of Anesthesiology, Harvard Medical School, Brigham & Women’s Hospital, Boston, Massachusetts
| | - Sharika Rajan
- Department of Neurology, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
| | - Jeffrey White
- Department of Neurology, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
| | - Jenniffer Garcia
- Department of Neurology, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
| | - Christopher Gibbons
- Department of Neurology, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
| | - Roy Freeman
- Department of Neurology, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
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Cerebellar-cerebral dynamic functional connectivity alterations in major depressive disorder. J Affect Disord 2020; 275:319-328. [PMID: 32734925 DOI: 10.1016/j.jad.2020.06.062] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 05/14/2020] [Accepted: 06/14/2020] [Indexed: 12/20/2022]
Abstract
BACKGROUND The cerebellum plays an important role in the neural mechanism of depression and its static functional connectivity (FC) with the cerebrum is disrupted in patients with major depressive disorder (MDD). However, cerebellar-cerebral dynamic FC alterations in MDD remain largely unknown. METHODS 50 patients with MDD and 36 well-matched healthy controls underwent resting-state functional magnetic resonance imaging. Cerebellar-cerebral dynamic FC analyses were performed using the cerebellar seeds previously identified as being involved in the executive, default-mode, affective-limbic, and motor networks. Inter-group differences in the cerebellar dynamic FC and their associations with clinical and cognitive variables were examined. RESULTS Compared to healthy controls, patients with MDD had decreased cerebellar-cerebral dynamic FC of the cerebellar subregions connecting with the executive, default-mode and affective-limbic networks. The dynamic FC of the cerebellar subregion connecting with the affective-limbic network was related to severity of depression and anxiety symptoms in MDD patients. The dynamic FC of the cerebellar subregions connecting with the default-mode and affective-limbic networks were related to sustained attention and prospective memory in controls, while the correlations were inverse or non-significant in patients. LIMITATIONS The fairly modest sample size and potential medication effect may increase the instability of the results. CONCLUSIONS Our findings provide further evidence for the pivotal role of the cerebellum in the neuropathology of depression, pointing to potential targets of cerebellar-cerebral pathways for alternative intervention or monitoring therapeutic responses.
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Abstract
Neural oscillations play an important role in the integration and segregation of brain regions that are important for brain functions, including pain. Disturbances in oscillatory activity are associated with several disease states, including chronic pain. Studies of neural oscillations related to pain have identified several functional bands, especially alpha, beta, and gamma bands, implicated in nociceptive processing. In this review, we introduce several properties of neural oscillations that are important to understand the role of brain oscillations in nociceptive processing. We also discuss the role of neural oscillations in the maintenance of efficient communication in the brain. Finally, we discuss the role of neural oscillations in healthy and chronic pain nociceptive processing. These data and concepts illustrate the key role of regional and interregional neural oscillations in nociceptive processing underlying acute and chronic pains.
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Affiliation(s)
- Junseok A. Kim
- Division of Brain, Imaging and Behaviour, Krembil Brain Institute, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada
- Institute of Medical Science, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Karen D. Davis
- Division of Brain, Imaging and Behaviour, Krembil Brain Institute, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada
- Institute of Medical Science, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
- Department of Surgery, University of Toronto, Toronto, Ontario, Canada
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Mills EP, Akhter R, Di Pietro F, Murray GM, Peck CC, Macey PM, Henderson LA. Altered Brainstem Pain Modulating Circuitry Functional Connectivity in Chronic Painful Temporomandibular Disorder. THE JOURNAL OF PAIN 2020; 22:219-232. [PMID: 32896638 DOI: 10.1016/j.jpain.2020.08.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2019] [Revised: 08/12/2020] [Accepted: 08/22/2020] [Indexed: 11/29/2022]
Abstract
There is evidence from preclinical models of chronic pain and human psychophysical investigations to suggest that alterations in endogenous brainstem pain-modulation circuit functioning are critical for the initiation and/or maintenance of pain. Whilst preclinical models have begun to explore the functioning of this circuitry in chronic pain, little is known about such functioning in humans with chronic pain. The aim of this investigation was to determine whether individuals with chronic non-neuropathic pain, painful temporomandibular disorders (TMD), display alterations in brainstem pain-modulating circuits. Using resting-state functional magnetic resonance imaging, we performed static and dynamic functional connectivity (FC) analyses to assess ongoing circuit function in 16 TMD and 45 control subjects. We calculated static FC as the correlation of functional magnetic resonance imaging signals between regions over the entire scan and dynamic FC as the correlation of signals in short (50s) windows. Compared with controls, TMD subjects showed significantly greater (static) FC between the rostral ventromedial medulla and both the subnucleus reticularis dorsalis and the region that receives orofacial nociceptive afferents, the spinal trigeminal nucleus. No differences were found in other brainstem pain-modulating regions such as the midbrain periaqueductal gray matter and locus coeruleus. We also identified that TMD subjects experience greater variability in the dynamic functional connections between the rostral ventromedial medulla and both the subnucleus reticularis dorsalis and spinal trigeminal nucleus. These changes may underlie enhanced descending pain-facilitating actions over the region that receives nociceptive afferents, ultimately leading to enhanced nociceptive transmission to higher brain regions and thus contributing to the ongoing perception of pain. PERSPECTIVE: Psychophysical studies suggest that brainstem pain-modulation circuits contribute to the maintenance of chronic pain. We report that individuals with painful TMD display altered static and dynamic FC within the brainstem pain-modulation network. Modifying this circuitry may alter an individual's ongoing pain.
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Affiliation(s)
- Emily P Mills
- Department of Anatomy and Histology, University of Sydney, Sydney, New South Wales, Australia
| | - Rahena Akhter
- Sydney Dental School, University of Sydney, Sydney, New South Wales, Australia
| | - Flavia Di Pietro
- Department of Anatomy and Histology, University of Sydney, Sydney, New South Wales, Australia
| | - Greg M Murray
- Sydney Dental School, University of Sydney, Sydney, New South Wales, Australia
| | - Chris C Peck
- Sydney Dental School, University of Sydney, Sydney, New South Wales, Australia
| | - Paul M Macey
- UCLA School of Nursing and Brain Research Institute, University of California, Los Angeles, California
| | - Luke A Henderson
- Department of Anatomy and Histology, University of Sydney, Sydney, New South Wales, Australia.
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