American Journal of Neuroradiology 26:591-597, March 2005
© 2005 American Society of Neuroradiology
BRAIN
FLAIR Diffusion-Tensor MR Tractography: Comparison of Fiber Tracking with Conventional Imaging
a Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan, ROC
b Department of Radiology, Tri-Service General Hospital, Taipei, Taiwan, ROC
Address reprint requests to Cheng-Yu Chen, MD, Department of Radiology, Tri-Service General Hospital and National Defense Medical Center, No 325, Sec 2, Cheng-Kung Road, Neihu 114, Taipei, Taiwan, ROC
BACKGROUND AND PURPOSE: Partial volume with CSF is known to contaminate the quantification of white matter anisotropy depicted by diffusion tensor imaging (DTI). We hypothesized that the FLAIR technique helps to improve DTI white matter tractography in the normal adult brain by eliminating CSF partial volume effects.
METHODS: Seven healthy adults aged 2337 underwent both conventional and FLAIR DTI at 1.5T. Each subject was imaged five times. Neural fiber tractography was performed with both sequences by using two algorithms: a voxel-based method (EZ-tracing) with global seed points and another based on subvoxel tractography (tensor deflection) by using manual encircling of local seed points. Total volume of the fibers tracked was compared for the two types of images.
RESULTS: Fiber tracking was substantially most successful on FLAIR DTI near the lateral ventricles and the sulci, where CSF partial volume effects were likely present. Minor false tracts on FLAIR images, possibly due to a reduced signal-to-noise ratio, were found in regions relatively free of CSF contamination; however, they did not affect tracking of major periventricular white matter bundles, such as those related to the corpus callosum or the corona radiata. When we excluded false tracts, the FLAIR technique depicted an average of 17% more fibers in volume than conventional DTI in the periventricular regions (P < .0005, paired Student t test).
CONCLUSION: Despite the reduction of signal-to-noise ratio and longer imaging times, FLAIR improved tractography by eliminating CSF partial volume effects.
This article has been cited by other articles:
![]() |
M.-C. Chou, C.-Y. Wang, H.-S. Liu, H.-W. Chung, and C.-Y. Chen Pseudolesions Arising from Unfolding Artifacts in Diffusion Imaging with Use of Parallel Acquisition: Origin and Remedies AJNR Am. J. Neuroradiol., June 1, 2007; 28(6): 1099 - 1101. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Concha, D. W. Gross, and C. Beaulieu Diffusion Tensor Tractography of the Limbic System AJNR Am. J. Neuroradiol., October 1, 2005; 26(9): 2267 - 2274. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. D. Lascola Diffusion Tensor Tractography: Exploring the Cost-Benefit Ratio of Incorporating CSF Suppression into Fiber Tracing Algorithms AJNR Am. J. Neuroradiol., April 1, 2005; 26(4): 693 - 694. [Full Text] [PDF] |
||||
