title: 3.0T MRI tractography of lumbar nerve roots in disc herniation.
abstract: BACKGROUND
  Diffusion tensor imaging (DTI) with fiber tracking (FT) has found clinical applications in the evaluation of the central nervous system and has been extensively used to image white matter tract. The feasibility of FT of the lumbar nerve roots in disc herniation is unclear.
  
  
  OBJECTIVE
  To demonstrate the feasibility of FT in the lumbar nerve roots, and to assess potential differences in fractional anisotropy (FA) and apparent diffusion coefficient (ADC) of L4, L5, and S1 nerves between healthy disc and disc herniation.
  
  
  METHODS
  Twenty patients with unilateral sciatica related to posterolateral or foraminal disc herniation and 20 healthy volunteers were enrolled in our study. Anatomical fusion with the axial T2 sequences was used to estimate the relevance of reconstructions. DTI with tractography of the L4, L5, and S1 nerves was performed. Mean FA and ADC values were calculated from tractography images.
  
  
  RESULTS
  Lumbosacral root compression sites could be clearly identified on the tractography images. There was no significant difference in FA or ADC between left and right nerve roots at the same level (P > 0.05) in healthy volunteers. The mean FA value of the compressed spinal nerve roots was significantly lower than that of FA of the contralateral nerve roots (P = 0.0001). ADC was significantly higher in compressed nerve roots than that in the contralateral nerve root (P = 0.0002).
  
  
  CONCLUSIONS
  3 T magnetic resonance imaging (MRI) DTI and FT of the lumbosacral region nerve is possible. There are significant changes in FA and ADC values in the compressed L4, L5, and S1 nerves.
authors.affiliation: Shandong Medical Imaging Research Institute, Shandong University, Jinan, PR China lichuanting@yeah.net.
authors.forename: Li
authors.initials: L
authors.lastname: Chuanting
authors.affiliation: Shandong Medical Imaging Research Institute, Shandong University, Jinan, PR China.
authors.forename: Wang
authors.initials: W
authors.lastname: Qingzheng
authors.affiliation: Shandong Medical Imaging Research Institute, Shandong University, Jinan, PR China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Wenfeng
authors.affiliation: Shandong Medical Imaging Research Institute, Shandong University, Jinan, PR China.
authors.forename: Hui
authors.initials: H
authors.lastname: Yiyi
authors.affiliation: Shandong Medical Imaging Research Institute, Shandong University, Jinan, PR China.
authors.forename: Zhao
authors.initials: Z
authors.lastname: Bin
mesh_terms: D000328:Adult; D016880:Anisotropy; D056324:Diffusion Tensor Imaging / Q000379:methods; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D007405:Intervertebral Disc Displacement / Q000150:complications / Q000473:pathology*; D008159:Lumbar Vertebrae / Q000294:innervation* / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008280:Magnetics; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012585:Sciatica / Q000209:etiology / Q000473:pathology; D013126:Spinal Nerve Roots / Q000473:pathology*; D055815:Young Adult
keywords: Lumbar plexus; diffusion tensor imaging; disc disease; magnetic resonance imaging; tractography