Generating fiber crossing phantoms out of experimental DWIs.
In Diffusion Tensor Imaging (DTI), differently oriented fiber bundles inside one voxel are incorrectly modeled by a single tensor. High Angular Resolution Diffusion Imaging (HARDI) aims at using more complex models, such as a two-tensor model, for estimating two fiber bundles. We propose a new method for creating experimental phantom data of fiber crossings, by mixing the DWI-signals from high FA-regions with different orientation. The properties of these experimental phantoms approach the conditions of real data. These phantoms can thus serve as a 'ground truth' in validating crossing reconstruction algorithms. The angular resolution of a dual tensor model is determined using series of crossings, generated under different angles. An angular resolution of 0.67pi was found in data scanned with a diffusion weighting parameter b = 1000 s/mm2. This resolution did not change significantly in experiments with b = 3000 and 5000 s/mm2, keeping the scanning time constant.
Department of Radiology, Academic Medical Center, University of Amsterdam, NL. m.w.a.caan@tudelft.nl
Matthan W A
MW
Caan
Anne Willem
AW
de Vries
H Ganesh
HG
Khedoe
Erik M
EM
Akkerman
Lucas J
LJ
van Vliet
C A
CA
Grimbergen
Frans M
FM
Vos
D000465:Algorithms; D001921:Brain / Q000033:anatomy & histology*; D003198:Computer Simulation; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008959:Models, Neurological; D009413:Nerve Fibers, Myelinated / Q000648:ultrastructure*; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity