Effects of b-Matrix Correction on Fiber Tractography in High Resolution DTI with Short-Axis Propeller EPI
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چکیده
INTRODUCTION –Short-Axis Propeller EPI (SAP-EPI) has been shown to be very effective in obtaining highresolution, artifact-free DTI data [2]. One challenge with SAP-EPI is that in the presence of head rotation each blade of SAP-EPI data is potentially encoded with a different diffusionencoding direction (i.e. b-matrix) (Fig. 1). Since the diffusion-encoding is ‘imprinted’ on the magnetization, a simple counter-rotating of blades does not suffice. It has been shown recently that this necessitates non-linear methods to reconstruct diffusion tensors accurately [1]. In this study, we investigated the effects of our correction scheme on SAP-EPI and its consequences on tractography.
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