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This website has been deprecated and exists as an archive only.

The TORTOISE website has been moved to https://tortoise.nibib.nih.gov.

For any information about TORTOISE generation V3.x.x, please refer to the new website.

Introduction to TORTOISE

Tolerably Obsessive Registration and Tensor Optimization Indolent Software Ensemble

The Seventh TORTOISE Course will be on March 12th, 2018

Go to the events page to view the agenda, get updated software, and a sample dataset.

Please download the documentation for TORTOISE V3.1.1

MAC users: untar the file using the following command: tar -zxvf DOCUMENTATION_TORTOISE_v311.tar.gz and it will be downloaded in the downloads folder.

Please open TORTOISE_main_documentation.html from the DOCUMENTATION_TORTOISE_v311 folder in any browser and it should guide you through the new TORTOISE usage.

Read the version update notes for version update information for versions prior to 3.0.0.

Please join the TORTOISE DTI Google Group for questions and help.

For comments and suggestions, please visit our new public forum.

Why TORTOISE?

Our software is not for rabbit type people; if you need to process diffusion data at the scanner console you do not want to use our software.

Why obsessive?

We have realized that DTI is a wonderful quantitative technique which is unfortunately susceptible to all sorts of artifacts and confounds. We spent a lot of time trying to obtain reliable DTI measurements, which has made ourselves and our software a little obsessive.

Why indolent?

Our emphasis has been on developing conceptually rigorous routines more than optimizing the speed and user-friendliness of the software.

TORTOISE logo

TORTOISE was presented at the ISMRM meeting in Stockholm, Sweden in 2010. Please reference the following abstract if you use TORTOISE in your work.

C. Pierpaoli, L. Walker, M.O. Irfanoglu, A. Barnett, P. Basser, L-C. Chang, C. Koay, S. Pajevic, G. Rohde, J. Sarlls, and M. Wu, 2010, TORTOISE: an integrated software package for processing of diffusion MRI data, ISMRM 18th Annual Meeting, Stockholm, Sweden, #1597 .

TORTOISE Modules

The TORTOISE software package is for processing diffusion MRI data, and it contains three main modules:

  • DIFF_PREP: software for image resampling, motion, eddy current distortion, and EPI distortion correction using a structural image as target, and for re-orientation of data to a common space
  • DIFF_CALC: software for tensor fitting, error analysis, directionally encoded color map visualization and ROI analysis
  • DR-BUDDI: software for EPI distortion correction using pairs of diffusion data sets acquired with opposite phase encoding (blip-up blip-down acquisitions).

In addition, TORTOISE contains additional utilities, such as a tool for the analysis of multi-center phantom data.

Some common questions and answers about our software packages are listed in the FAQ.

If you are interested in contributing to these wiki pages, please contact us in order to create an account for you.

For internal NIH collaborators only