Diffusion-tensor fiber tractography: intraindividual comparison of 3.0-T and 1.5-T MR imaging.
OBJECTIVE
To prospectively evaluate the depiction of brain fiber tracts at 3.0- versus 1.5-T diffusion-tensor (DT) fiber tractography performed with parallel imaging.


METHODS
Institutional review board approval was obtained, and each subject provided written informed consent. Subjects were 30 healthy volunteers (15 men, 15 women; mean age, 28 years; age range, 21-46 years). Single-shot spin-echo echo-planar magnetic resonance (MR) sequences with parallel imaging were applied. Four fiber tracts were reconstructed: corticospinal tract (CST), superior longitudinal fasciculus (SLF), corpus callosum (CC), and fornix. Two neuroradiologists compared 3.0- and 1.5-T tractography in terms of fiber tract depiction by using five depiction scores (scores 0-4) and numbers of reconstructed tract fibers and in terms of lateral asymmetry in the CST by using numbers of reconstructed fibers. The Wilcoxon signed rank test was applied for statistical analysis.


RESULTS
Visual scores for both CST hemispheres (P < .001), the right SLF (P = .005), the CC (P = .01), and the right fornix (P = .04) were higher at 3.0-T DT tractography. Larger numbers of CST (right, P = .008; left, P < .001), SLF (right, P = .001; left, P = .02), and fornix (bilaterally, P = .02) tract fibers were depicted at 3.0 T. The asymmetry index for the CST was lower (P < .001) at 3.0 T. Visual scores for the left SLF and the left fornix and numbers of CC tract fibers were not significantly different.


CONCLUSIONS
Depiction of most fiber tracts was improved at 3.0-T DT tractography compared with depiction at 1.5-T tractography.
Okada
Tsutomu
T
Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, and Human Brain Research Center, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto-shi, Kyoto 606-8507, Japan.
Miki
Yukio
Y
Fushimi
Yasutaka
Y
Hanakawa
Takashi
T
Kanagaki
Mitsunori
M
Yamamoto
Akira
A
Urayama
Shin-Ichi
S
Fukuyama
Hidenao
H
Hiraoka
Masahiro
M
Togashi
Kaori
K
D000328:Adult; D001921:Brain / Q000033:anatomy & histology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies