FIG. 3.
Pulse sequence diagrams of SLINCYL MRA. a: Basic block P. b: Additional block Q for fluid suppression. c: Pulse sequence diagram of each slab. Nseg repetitions of block P are surrounded by block Q and Trecovery,Q for fluid suppression. d: modified sequence for fluid-suppression (illustrated with Ns = 6, Ng = 3, and Ncy = 18). Block Q (before each dark slab) and Trecovery,Q (after each dashed slab) pairs are applied once per every Ng = 3 slabs. In addition, the assignment of an interleaved subset of cylinders to each slab is modified such that slabs acquired immediately after blocks Q collect the Ns/Ng (=2) innermost cylinders. This scheme captures the transient contrast more effectively than the case with the original assignment (indices within brackets). e: Further modified sequence for fluid-suppression. A total of 180 slabs are acquired by interleaving the lower (slab indices 91 to 180) and upper (1 to 90) half the slabs. In this way, no overlap exists between any adjacent sets of Ng = 3 slabs and the explicit recovery time Trecovery,Q is no longer necessary.