Optimal tag pattern validation using magnetic resonance imaging

Magnetic resonance (MR) tagging is a technique used to impose a known intensity pattern, called a tag pattern, on an object by spatially modulating the object's proton spin density before the image is acquired. Since the tag pattern moves with the object, MR tagging is particularly useful in the estimation of deformable motion from MR image sequences because some tag patterns can resolve motion ambiguities such as the aperture problem and improve the accuracy of optical flow motion estimates. We present an experimental validation of the tag pattern optimization method of Denney and Prince (see Proc. of the IEEE Int'l Conf. Acoustics, Speech, and Signal Processing, p.V225-V228, Minneapolis, April 1993, and IEEE Transactions on Image Processing, vol.3, no.2, p.178-191, March 1994) in a practical MR imaging environment. This experiment includes a study of the effects of temporal sampling on the optimal frequency that was not done by Denney et. al. Our experimental results show that the tag pattern optimization method of Denney et. al. is valid in a practical MR imaging application.