title: Cortical and white matter alterations in patients with neuropathic pain after spinal cord injury.
abstract: Neuropathic pain is one of the major problems of patients with spinal cord injury (SCI), which remains refractory to treatment despite a variety of therapeutic approach. Multimodal neuroimaging could provide complementary information for brain mechanisms underlying neuropathic pain, which could be based on development of more effective treatment strategies. Ten patients suffering from chronic neuropathic pain after SCI and 10 healthy controls underwent FDG-PET, T1-anatomical MRI and diffusion tensor imaging. We found decreases of both metabolism and the gray matter volume in the left dorsolateral prefrontal cortex in patients compared to healthy controls, as well as hypometabolism in the medial prefrontal cortex and gray matter volume loss in bilateral anterior insulae and subgenual anterior cingulate cortices. These brain regions are generally known to participate in pain modulation by affective and cognitive processes. Decreases of mean diffusivity (MD) in the right internal capsule including, cerebral peduncle, pre-and post-central white matter, and prefrontal white matter as components of the corticospinal and thalamocortical tracts were demonstrated in patients. Further, lower MD value of prefrontal white matter was correlated with decreased metabolism of medial prefrontal cortex in patients. These results indicated that white matter changes imply abnormal pain modulation in patients as well as motor impairment. Our study showed the functional and structural multimodal imaging modality commonly identified the possible abnormalities in the brain regions participating pain modulation in neuropathic pain. Multifaceted imaging studies in neuropathic pain could be useful elucidating precise mechanisms of persistent pain, and providing future directions for treatment.
authors.affiliation: Department of Nuclear Medicine, Seoul National University College of Medicine, 103 Daehak-ro, Jongno-gu, Seoul 110-799, Republic of Korea; Department of Nuclear Medicine, Seoul Metropolitan Government Seoul National University Boramae Medical Center, 20, Boramae-ro 5-gil, Dongjak-gu, Seoul 156-707, Republic of Korea.
authors.forename: Eun Jin
authors.initials: EJ
authors.lastname: Yoon
authors.forename: Yu Kyeong
authors.initials: YK
authors.lastname: Kim
authors.forename: Hyung Ik
authors.initials: HI
authors.lastname: Shin
authors.forename: Youngjo
authors.initials: Y
authors.lastname: Lee
authors.forename: Sang Eun
authors.initials: SE
authors.lastname: Kim
mesh_terms: D000328:Adult; D001369:Axons / Q000473:pathology*; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology*; D056324:Diffusion Tensor Imaging; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D009437:Neuralgia / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology* / Q000503:physiopathology*; D049268:Positron-Emission Tomography; D013119:Spinal Cord Injuries / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology*
chemical_list: D019788:Fluorodeoxyglucose F18
keywords: DTI; FDG-PET; MRI; Neuropathic pain; Spinal cord injury