A method includes creating a second set of projection data that includes substantially only selected structure of interest based on a first set of projection data that includes the selected structure of interest and other structure. Another method includes generating a second plurality of sliding window slices for a last slice of a first plurality of slices, selecting a second sliding window slice from the second plurality of sliding window slices based on the last slice of the first plurality of slices, and generating a second plurality of slices, including a first slice and a last slice, from a range of projection data around projection data corresponding to the last slice of the first plurality of slices.
