Chronic pain has a tremendous impact on individual patients, their families, and society. Functional magnetic resonance imaging (fMRI) has been used to investigate nociceptive processing and central sensitization in the brain to better understand, and to ultimately develop improved therapies for chronic pain. The spinal cord is important in the processing of nociception, and direct animal and indirect psychophysical and behavioral human studies have demonstrated its role in the generation and maintenance of hyperalgesia and allodynia. Our overall goals are to use human spinal fMRI to elucidate mechanisms of nociceptive processing and spinal cord plasticity in healthy subjects and patients with chronic neuropathic pain. Our Hypotheses are that: (1) increases in noxious thermal stimuli will produce a corresponding increase in fMRI signal activation in the human spinal dorsal horn and increases in spatial and rostrocaudal activity; (2) a thermal-capsaicin induced experimental allodynia/hyperalgesia model and (3) chronic upper extremity neuropathic pain will result in increased spinal dorsal horn activity to non-noxious mechanical stimuli with increased rostrocaudal and spatial activity compared to the unaffected side.
Specific AIMS : (1) optimize human spinal fMRI by characterizing the hemodynamic impulse response function; (2) characterize spinal cord activity (fMRI signal and spatial activation properties) in response to noxious thermal stimuli and compare to non-noxious mechanical and thermal stimuli; (3) elucidate the response of the human spinal cord to a heat/capsaicin pain model of allodynia and hyperalgesia in response to normally non-noxious mechanical stimuli; (4) characterize dorsal horn responsiveness to normally non- noxious thermal and tactile stimuli in patients with chronic neuropathic pain. We also plan to compare spinal fMRI activation patterns from noxious thermal stimuli in healthy subjects with normally non-noxious but painfully perceived thermal stimuli in chronic neuropathic pain patients. This will provide further insight into mechanisms of spinal plasticity in chronic neuropathic pain. Significance: These studies will advance our understanding of nociceptive processing in the human spinal cord and the effects of neural plasticity in experimental pain models and chronic neuropathic pain. This will enhance our knowledge of how chronic pain states are generated, maintained, and potentially treated. Furthermore, we will have a more objective means of assessing neural function in patients with peripheral nerve and spinal cord injury. ? ?

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
5R01NS053961-02
Application #
7167421
Study Section
Somatosensory and Chemosensory Systems Study Section (SCS)
Program Officer
Porter, Linda L
Project Start
2006-01-09
Project End
2010-12-31
Budget Start
2007-01-01
Budget End
2007-12-31
Support Year
2
Fiscal Year
2007
Total Cost
$340,821
Indirect Cost
Name
Stanford University
Department
Anesthesiology
Type
Schools of Medicine
DUNS #
009214214
City
Stanford
State
CA
Country
United States
Zip Code
94305
Bagarinao, Epifanio; Johnson, Kevin A; Martucci, Katherine T et al. (2014) Preliminary structural MRI based brain classification of chronic pelvic pain: A MAPP network study. Pain 155:2502-9
Nilakantan, Aneesha; Younger, Jarred; Aron, Arthur et al. (2014) Preoccupation in an early-romantic relationship predicts experimental pain relief. Pain Med 15:947-53
Bruehl, Stephen; Apkarian, A Vania; Ballantyne, Jane C et al. (2013) Personalized medicine and opioid analgesic prescribing for chronic pain: opportunities and challenges. J Pain 14:103-13
Nash, Paul; Wiley, Katherine; Brown, Justin et al. (2013) Functional magnetic resonance imaging identifies somatotopic organization of nociception in the human spinal cord. Pain 154:776-81
Kong, Jiang-Ti; Johnson, Kevin A; Balise, Raymond R et al. (2013) Test-retest reliability of thermal temporal summation using an individualized protocol. J Pain 14:79-88
Mackey, Sean; Carroll, Ian; Emir, Birol et al. (2012) Sensory pain qualities in neuropathic pain. J Pain 13:58-63
Chapin, Heather; Bagarinao, Epifanio; Mackey, Sean (2012) Real-time fMRI applied to pain management. Neurosci Lett 520:174-81
Carroll, Ian; Barelka, Peter; Wang, Charlie Kiat Meng et al. (2012) A pilot cohort study of the determinants of longitudinal opioid use after surgery. Anesth Analg 115:694-702
Lawrence, Jane M; Hoeft, Fumiko; Sheau, Kristen E et al. (2011) Strategy-dependent dissociation of the neural correlates involved in pain modulation. Anesthesiology 115:844-51
Harden, R Norman; Bruehl, Stephen; Perez, Roberto S G M et al. (2010) Validation of proposed diagnostic criteria (the ""Budapest Criteria"") for Complex Regional Pain Syndrome. Pain 150:268-74

Showing the most recent 10 out of 28 publications