Projects:RegistrationEvaluation
Contents
Evaluation of Registration
We are interested in comparing existing registration packages to determine how registration in Slicer3 can be improved. This work focuses on examining various packages researchers are currently using for registration and comparing results on a set of examples representative of common registration tasks. Finally, we propose the development of a testbed, where registration packages can be compared and parameters suitable for a given domain (e.g. multi-modal brain registration) can be determined.
Registration Packages
ITK
Work in progress.
Slicer3 RegisterImages
Work in progress.
RView
Work in progress.
Example 1: Fixing Artifacts in DWI
The DWI data consists of 13 volumes -- a b0 and 12 gradient directions. This process was conducted 3 times per patient for a total of 39 volumes. The image below shows a particular slice in all 12 gradient directions and all 3 scans where the artifacts can clearly be seen in some of the gradient directions.
Method 1: Slice by Slice 2D Registration
The problem can be alleviated by 2D registration between slices of a corrupted volume with the corresponding slice from the b0 volume, in which we assume the artifact is not present.
Affine Registration
Here we will restrict our investigation to affine transformations between images. We now consider different registration packages applied to this problem.
ITK
Using ITK modules, we wrote an application to perform 2D affine transformation with the following parameters:
- Similarity Metric: MattesMutualInformationImageToImageMetric with 24 bins and 10000 samples per bin.
- Interpolation: LinearInterpolateImageFunction
- Optimization: RegularStepGradientDescentOptimizer with a minimum step length of 0.001, a maximum step length of 1.0, 200 iterations, and a relaxation factor of 0.8.
Method 1: 3D Registration
The problem can be alleviated by 3D registration between a corrupted volume with and the b0 volume, in which we assume the artifact is not present.
Affine Registration
Here we will restrict our investigation to an affine transformation between images. We now consider different registration packages applied to this problem.
ITK
Work in progress.
