Diffusion tensor tractography of the lower spinal cord.
BACKGROUND
We employed a diffusion-tensor (DT) imaging technique involving a single-shot echo-planar sequence in combination with parallel imaging for tractography of the lower spinal cord and assessed the feasibility of this technique.


METHODS
Images were obtained at 1.5 T using a five-channel receiver coil. We used a single-shot echo-planar sequence with parallel imaging to acquire diffusion-weighted (DW) images in the axial plane with phase encoding in the right-left direction. A motion-probing gradient was applied in six directions with a b-value of 1,000 s/mm(2). The scan time was 5 min 15 s. On a reconstructed DW image in the sagittal plane, the spinal cord was included in a single region-of-interest to generate a tractogram of the entire cord in seven volunteers and nine patients with spinal canal stenosis or vertebral metastasis.


RESULTS
In each subject, although the conus medullaris and cauda equina were continuously visualized, the cord was demonstrated as a bundle of tracts color-coded in the z-axis. Nerve roots were depicted showing color-coding in the x- and y-axes. In the patient group, displacement of the cord was depicted showing changes in the color of the cord. Displacement of the proximal nerve roots was also depicted in the two patients with vertebral metastasis.


CONCLUSIONS
DT imaging using parallel imaging shows potential as a method for routine tractography of the lower spinal cord.
Tsuchiya
Kazuhiro
K
Department of Radiology, Kyorin University School of Medicine, 6-20-2, Shinkawa, Mitaka, Tokyo 181-8611, Japan. tsuchiyak-kyr@umin.ac.jp
Fujikawa
Akira
A
Honya
Keita
K
Nitatori
Toshiaki
T
Suzuki
Yuriko
Y
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D017352:Echo-Planar Imaging; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D013116:Spinal Cord / Q000033:anatomy & histology*; D013122:Spinal Diseases / Q000473:pathology*