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1. Introduction to DIFF_CALC

Welcome to the DIFF_CALC software guide. In this document, details about the properties and usage of the software will be described.

Diffusion Tensor Imaging (DTI) is a Magnetic Resonance Imaging (MRI) modality, which allows in-vivo extraction of brain neural pathways. DTI requires a scan with at least 6 diffusion weighted volumes obtained with non-colinear diffusion gradient directions in addition to at least one diffusion-free T2W image (b0 image).

The purpose of this software is to enable users to perform accurate tensor estimation, and create tensor derived metric maps. This software also includes basic visualization tools, ROI utilities and the capability to export the tensor and/or raw data to other software packages.

The recommended procedure for DTI processing would be to first correct for eddy distortions, motion and susceptibility induced EPI distortions using DIFF_PREP, then to estimate your tensor with DIFF_CALC.