US 11,852,709 B2
Systems and methods for low-field fast spin echo imaging
Hadrien A. Dyvorne, New York, NY (US); Laura Sacolick, Guilford, CT (US); Rafael O'Halloran, Guilford, CT (US); and Carole Lazarus, Paris (FR)
Assigned to Hyperfine Operations, Inc., Guilford, CT (US)
Filed by Hyperfine Operations, Inc., Guilford, CT (US)
Filed on Jan. 19, 2023, as Appl. No. 18/098,919.
Application 18/098,919 is a continuation of application No. 17/334,001, filed on May 28, 2021, granted, now 11,561,272.
Claims priority of provisional application 63/031,991, filed on May 29, 2020.
Prior Publication US 2023/0160988 A1, May 25, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. G01R 33/561 (2006.01); G01R 33/54 (2006.01); G01R 33/36 (2006.01); G01R 33/48 (2006.01); G01R 33/44 (2006.01); G01R 33/56 (2006.01)
CPC G01R 33/5618 (2013.01) [G01R 33/3607 (2013.01); G01R 33/445 (2013.01); G01R 33/4824 (2013.01); G01R 33/543 (2013.01); G01R 33/5602 (2013.01); G01R 33/5613 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A magnetic resonance imaging (MRI) system, comprising:
at least one radio frequency (RF) coil for transmitting and/or receiving RF pulses;
a direct digital synthesizer (DDS) coupled to the at least one RF coil; and
at least one controller configured to operate the at least one RF coil in accordance with a pulse sequence having a plurality of pulse repetition periods;
wherein, during one pulse repetition period of the plurality of pulse repetition periods, the at least one controller is configured to operate the at least one RF coil using a quadratic phase cycling scheme by modifying a phase of a waveform generated by the DDS and to:
control the at least one RF coil to generate a plurality of first RF pulses; and
control the at least one RF coil to generate a second RF pulse to deflect a net
magnetization vector associated with a subject being imaged by the MRI system from a transverse plane to a longitudinal plane.