Similarity Measures for Cardiac Diffusion Tensor Imaging Registration

The purpose of this paper is to register ex-vivo cardiac diffusion tensor images using affine transformations and the preservation of the principal direction reorientation strategy. We have successfully registered cardiac DTI and compared five different similarity measures: relative anisotropy difference, modulus difference, tensor difference, normalized tensor difference and principal direction difference. Results indicate that the principal direction difference is superior to the other similarity measures, followed by the normalized tensor difference and tensor difference. For cardiac DTI registration, measures sensitive to the full tensor perform better than scalar derived measures.