Slicer, or 3D Slicer, is a free, open source software package for visualization and image analysis. It includes tools for segmentation, rendering, registration of MRI, CT, US, nuclear medicine, and microscopy images.
To run this software interactively in a Linux environment run the commands (NOTE: second command is case-sensitive):
module load slicer3d Slicer
The documentation can be found at the website http://www.slicer.org/slicerWiki/index.php/Documentation