Multi-shot echo planar imaging using reordered segments and recursive radio frequency pulse design giving matched slice profiles across segments

A method for designing radio frequency (RF) pulses for use in a multi-shot pulse sequence implemented with a magnetic resonance imaging (MM) system, the method comprising:

• recursively designing a plurality of RF pulses with a computer system by:
• (a) selecting a desired number of RF pulses to design for a series of RF pulses, wherein the series of RF pulses comprises a last RF pulse and one or more preceding RF pulses;
• (b) selecting a flip angle for the last RF pulse using the computer system;
• (c) recursively assigning a flip angle for each of the one or more preceding RF pulses based on the flip angle selected for the last RF pulse, using the computer system;
• (d) computing a target slice profile using the computer system, the target slice profile defining a desired spatial profile of transverse magnetization in an imaging slice;
• (e) computing an RF pulse waveform for each of the plurality of RF pulses to achieve the target slice profile by:
• computing an RF pulse waveform for an initial RF pulse in the plurality of RF pulses based on the target slice profile;
• for each successive RF pulse in the plurality of RF pulses, measuring a residual longitudinal magnetization remaining after each one of the plurality of RF pulses preceding a current RF pulse and incorporating the residual longitudinal magnetization into the RF pulse waveform design for the current RF pulse;
• and
• (f) storing in the computer system as RF pulse parameters:
• the flip angle for the last RF pulse;
• each flip angle for the one or more preceding RF pulses;
• the RF pulse waveform for the initial RF pulse in the plurality of RF pulses;
• and
• each RF pulse waveform for each successive RF pulse in the plurality of RF pulses.