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FIG 1. Single-shot diffusion-weighted imaging with the SPLICE acquisition technique.
A, Sequence of RF pulses and magnetic field gradients. Diffusion weighting is achieved by a spin-echo preparation with strong gradients applied before and after the 180° refocusing pulse. The modified fast spin-echo train with two families of signals (E1 and E2) is generated by repetition of the elements inside the box. Two complete magnitude images from echo trains E1 and E2, respectively, should be added to obtain the final image with higher SNR.
B, Phase-encoding steps for half-Fourier reconstruction from the signals in echo train E1 and E2, respectively. Sixty-four lines in the final image are considered in the given example.
C, Phase encoding with centric reordering of the steps for an acquisition of a complete raw data matrix with 64 steps. Data recording starts after six cycles in the fast spin-echo train. This delay allows the spin system to reach an equilibrium state with similar signal intensities in both echo families E1 and E2.
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