1. From Scalars to Tensors: How to add new volume types?
Raul San Jose, BWH, LMI
Steve Pieper, Isomics
Alex Yarmarkovich, Isomics

2. Goals Support Diffusion Tensor Imaging
Port Slicer 2 functionality in terms of visualization and analysis.
Make DTI a core feature so it becomes a native Slicer 3 type.
Community can contribute/integrate their DTI analysis work based upon this core functionality.
Challenges: Move from Only Scalars thinking to other Volume types.

3. The good news
Diffusion Weighted Images and Diffusion Tensor Images can be read (write pending) into Slicer 3.
Corresponding MRML nodes are created.
Display MRML nodes are in place.
Storage done through vtkNRRDReader
CLP support this new node types: You can now integrate your favorite ITK DTI filter into Slicer 3.
Tensor estimation through Teem: Least Squares, Weighted Least Squares, Maximum Likelihood.

4. How to add a new volume type
Libs/MRML
vtkMRMLMyTypeVolumeNode
vtkMRMLMyTypeVolumeDisplayNode
Node
Storage
Display
vtkMRMLMyTypeReaderStorageNode
Base/Logic
vtkSlicerVolumesLogic
VtkSlicerLayerLogic
vtkSlicerMyTypeOptionsLogic
I/O
Layer
vtkSlicerVolumesGUI
Base/GUI
vtkSlicerMyTypeVolumeDisplayWidget
Display
Options
vtkSlicerMyTypeVolumeOptionsWidget

5. How to add a new volume type
Making the new type available to the Command line module
Command Line Module
vtkCommandLineModuleLogic

6. MRML DTI Nodes Class Hierarchy
(vtkMRML)Node
TransformableNode
VolumeNode
NRRDStorageNode
ScalarVolumeNode
DiffusionWeightedVolumeNode
TensorVolumeNode
DisplayNodes
VectorVolumeNode
DiffusionTensorVolumeNode