Patent ID: 11860258
Assignee: UNIVERSITY OF VIRGINIA PATENT FOUNDATION
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 10:
11. A magnetic resonance imaging (MRI) system, comprising:
a control sequencer coupled to a gradient subsystem comprising gradient amplifiers and gradient coils and an MRI subsystem comprising a static z-axis magnet and one or more radio frequency (RF) coils; and
a data acquisition and display (DADC) device comprising memory comprising programmed instructions stored thereon and one or more processors configured to execute the stored programmed instructions to:
generate a RF excitation pulse to produce transverse magnetization that generates a nuclear magnetic resonance (NMR) signal and a series of RF refocusing pulses to produce a corresponding series of NMR spin-echo signals;
modify an original encoding gradient waveform comprising a non-rectilinear encoding trajectory by one or more of:
adjusting at least a portion of the original encoding gradient waveform while maintaining substantially the same zeroth moment for the at least a portion of the original encoding gradient waveform; or
introducing at least one additional waveform segment, having a zeroth moment of substantially zero, at one or both ends of the original encoding gradient waveform;

generate during an interval adjacent to each of the series of RF refocusing pulses a first gradient pulse, wherein at least one of the first gradient pulses is generated according to the modified gradient waveform, the first gradient pulses encode the NMR spin-echo signals, a Maxwell integral is substantially zero at a spin-echo time associated with the modified encoding gradient waveform, and a magnitude of the Maxwell integral is substantially equal at each of a beginning and an end of the modified encoding gradient waveform; and
construct an image from generated digitized samples of the NMR spin-echo signals obtained based on the encoding.