title: Normal Values of Diffusion Tensor Magnetic Resonance Imaging Parameters in the Cervical Spinal Cord.
abstract: METHODS
  Prospective study.
  
  
  OBJECTIVE
  We evaluated the usefulness of diffusion tensor imaging (DTI) in diagnosing patients with cervical myelopathy by determining the accuracy of normal DTI parameter values.
  
  
  BACKGROUND
  DTI can visualize white matter tracts in vivo and quantify anisotropy. DTI is known to be more sensitive than conventional magnetic resonance imaging (MRI) in detecting subtle pathological changes of the spinal cord.
  
  
  METHODS
  A total of 31 normal subjects (13 men and 18 women; age, 23-87 years; mean age, 46.0 years) were included in this study. The patients had no symptoms of myelopathy or radiculopathy. A Philips Achieva 3-Tesla MRI with SE-type Single Shot EPI was used to obtain diffusion tensor images. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values were measured as DTI parameters on axial sections of several cervical levels. Subjects were divided into two groups: >40 years (n=16) and ≤40 years (n=15). A paired t-test was used to compare significant differences between the groups. ADC and FA values were most stable on axial sections.
  
  
  RESULTS
  For all subjects, mean ADC and FA values were 1.06±0.09×10(-3) mm(2)/sec and 0.68±0.05, respectively. ADC was significantly higher in subjects >40 years of age than in those ≤40 years. There was no significant difference in FA values between the two groups. The mean ADC value was significantly higher in normal subjects >40 years of age than in those ≤40 years.
  
  
  CONCLUSIONS
  It is important to consider age when evaluating cervical myelopathy by DTI.
authors.affiliation: Department of Orthopedic Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Chagawa
authors.affiliation: Department of Orthopedic Surgery, Sento Hill Hospital, Ube, Japan.
authors.forename: Shunka
authors.initials: S
authors.lastname: Nishijima
authors.affiliation: Department of Orthopedic Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Kanchiku
authors.affiliation: Department of Orthopedic Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Yasuaki
authors.initials: Y
authors.lastname: Imajo
authors.affiliation: Department of Orthopedic Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Hidenori
authors.initials: H
authors.lastname: Suzuki
authors.affiliation: Department of Orthopedic Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Yoshida
authors.affiliation: Department of Orthopedic Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Taguchi
keywords: Cervical spinal cord; Diffusion tensor imaging; Reference values