Anisotropic Interpolation of DT-MRI

Diffusion tensor MRI (DT-MRI) is an image modality that is gaining clinical importance. After some preliminaries that describe the fundamentals of this imaging modality, we present a new technique to interpolate the diffusion tensor field, preserving boundaries and the constraint of positive-semidefiniteness. Our approach is based on the use of the inverse of the local structure tensor as a metric to compute the distance between the samples and the interpolation point. Interpolation is an essential step in managing digital image data for many different applications. Results on resampling (zooming) synthetic and clinical DT-MRI data are used to illustrate the technique. This new scheme provides a new framework for anisotropic image processing, including applications on filtering, registration or segmentation.