Fig 2. Artifact and k-space trajectory.

The upper portion of the figure represents the acquired echo train from shot to shot as effective echo time increases; the solid line is a center-out acquisition common to most FSE schemes, while the dashed line demonstrates a later TE_eff using the given acquisition strategy. In the echo-prepared image, blurring (but not ghosting) is present. Both types of artifact exist in other sampling schemes, with the proposed Caesar cipher acquisition clearly being unsuited to Fourier-based reconstruction.