1NIMH, Bethesda, MD, United States
Recently Frydman et al proposed a mechanism for directly forming images in k space using frequency sweep encoding. It relies on the quadratic dependence of magnetization phase on position. In combination with EPI-type readout, this method has found applications in single-shot spin-echo imaging. Its sequential excitation of magnetization may also be used for novel image contrast generation. Fidelity of images directly formed in k space, however, is significantly degraded. Here we show that fidelity of this type of images can be restored and we also extend this method to susceptibility-weighted imaging.