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Alonso Ramírez-Manzanares1, Ramón Aranda2, Mariano Rivera2 and Omar Ocegueda2
1. University of Guanajuato 2. Centro de Investigación en Matemáticas (CIMAT)
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} B=1500 } NS=48
Intention: realistic clinical scenario
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3
MRI signal for a single fiber MRI signal for a 2 fiber crossing
Set of signals for the basis of DBFs
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Each signal is modeled as a positive linear combination of the DBFs
This leads to a non-negative least squares problem for each voxel v
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Homogeneity criterion 1:
Homogeneity criterion 2:
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} We applied the same approach as published in 2007 plus a different spatial regularization
} Spatial regularization should be used provided we have evidence that the local anatomical structure is sufficiently homogeneous ◦ Challenge: how can we infer that the anatomical
structure of a region is sufficiently homogeneous?
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b-value should be taken into account In the evaluation
Two-fiber crossing? Four-fiber crossing?
Accurate Diff. profile needed?
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