Alternate k-space sampling in EPI: compensation for T2* and adjustable T2 weighting.

In this work, preliminary results are described for a modification of the MBEST sampling scheme such that image resolution can be increased while preserving image contrast. In this new approach, a single spin-echo is used in sampling k-space. The basic idea relies on acquiring a conventional EPI image from the center of k-space and applying a pi pulse to permit the acquisition of the two outer edges of k-space. Using this new approach, it is possible to obtain an enhancement in EPI image resolution, while reducing the extent of T2* weighting. As a result, the resulting images possess reduced T2* contrast and suffer less signal loss from T2* effects such as spatial variations in susceptibility and field inhomogeneity.