Diffusion Tensor Analysis and Tractography - Introduction

The diffusion tensor imaging (DTI) toolkit is used to process diffusion weighted magnetic resonance images to produce images of the diffusion tensor and its scalar invariants, such as the tensor Trace, fractional anisotropy and colour direction images.

When the tensor image has been computed, it can be used to perform streamline tractography, and the fibre tracts can be viewed in Jim's 3-dimensional display.

To successfully compute the diffusion tensor, you will need a set of diffusion-weighted images with diffusion weighting in at least six independent directions, plus a non-diffusion-weighted (M0) image.

To start Jim's Diffusion Analysis Toolkit, select DTI Analysis from the Toolkits menu: toolkits_dti

The MRI Diffusion Analysis Toolkit will now appear, ready for you to start the analysis pipeline.

dti_toolkit_dialog

The Diffusion Toolkit contains an integrated 3-D display on the left, for you to visualise fibre tracts, and the processing tools to the right. There are two tabbed panes on the right: the first is for warp correction and calculation of the diffusion tensor; the second is for performing tractography.

The first task will be to define the gradient vectors and/or b-matrices that were used in the diffusion weighting of your set of images.

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