System for accelerated segmented MR image data acquisition
View Patent ↗A system for accelerated segmented magnetic resonance (MR) image data acquisition includes an RF (Radio Frequency) signal generator and a magnetic field gradient generator. The RF signal generator generates RF excitation pulses in anatomy and enabling subsequent acquisition of associated RF echo data. The magnetic field gradient generator generates magnetic field gradients for anatomical volume selection, phase encoding, and readout RF data acquisition in a three dimensional (3D) anatomical volume. The RF signal generator and the magnetic field gradient generator acquire consecutive segments of k-space line data representative of an individual image slice in a gradient echo method by adaptively varying RF excitation pulse flip angle between acquisition of the consecutive segments.
1. A system for accelerated segmented magnetic resonance (MR) image data acquisition, comprising:
an RF (Radio Frequency) signal generator for generating RF excitation pulses in anatomy and enabling subsequent acquisition of associated RF echo data; and
a magnetic field gradient generator for generating magnetic field gradients for anatomical volume selection, phase encoding, and readout RF data acquisition in a three dimensional (3D) anatomical volume,
wherein said RF signal generator and said magnetic field gradient generator are configured to acquire temporally consecutive segments of k-space line data representative of a first individual image slice in a gradient echo method by adaptively varying an RF excitation pulse flip angle between acquisition of the temporally consecutive segments before acquiring temporally consecutive segments of k-space line data representative of a second individual image slice, and
wherein the adaptive variation of the RF excitation pulse flip angles is calculated to provide an equal magnetization across segments.
2. The system according to claim 1 ,
wherein said temporally consecutive segments comprise temporally consecutive segments of calibration k-space line data, and
wherein said RF signal generator and said magnetic field gradient generator are further configured to acquire said temporally consecutive segments using a parallel imaging technique.
3. The system according to claim 2 , wherein
said RF signal generator and said magnetic field gradient generator are further configured to acquire additional temporally consecutive segments of calibration k-space line data representative of successive individual image slices.
4. The system according to claim 2 , wherein
said RF signal generator and said magnetic field gradient generator are further configured to acquire additional temporally consecutive segments of calibration k-space line data representative of successive individual image slices.
5. The system according to claim 2 ,
wherein said parallel imaging technique is a GRAPPA (Generalized Autocalibrating Partially Parallel Acquisition) accelerated parallel imaging technique, and
wherein said calibration k-space line data comprises auto-calibration k-space line data of the GRAPPA accelerated parallel imaging technique.
6. The system according to claim 2 , wherein
said temporally consecutive segments of calibration k-space line data are temporally consecutive for said individual image slice and interleaved in k-space.
7. The system according to claim 1 , wherein
said RF signal generator is further configured to provide three RF pulses of varying RF excitation pulse flip angles for acquisition of three temporally consecutive segments comprising said individual image slice, said RF excitation pulse flip angles comprising flip angles of 35.1 degrees for segment 1 , 45 degrees for segment 2 , and 90 degrees for segment 3 .
8. The system according to claim 1 , wherein
said system is configured to provide the RF excitation pulse flip angles for acquisition of said temporally consecutive segments such that an applied RF excitation signal is substantially equal for acquisition of each temporally consecutive segment included in said temporally consecutive segments.
9. A system for accelerated segmented magnetic resonance (MR) image data acquisition, comprising:
an RF (Radio Frequency) signal generator for generating RF excitation pulses in anatomy and enabling subsequent acquisition of associated RF echo data; and
a magnetic field gradient generator for generating magnetic field gradients for anatomical volume selection, phase encoding and readout RF data acquisition in a three dimensional (3D) anatomical volume,
wherein said RF signal generator and said magnetic field gradient generator are configured to acquire temporally consecutive segments of k-space line data representative of a first individual image slice using a spin echo technique comprising a first RF excitation pulse producing a 90 degree flip angle, followed by 180 degree refocusing pulses to form spin-echoes for each segment comprising said individual image slice before acquiring temporally consecutive segments of k-space line data representative of a second individual image slice.
10. The system according to claim 9 ,
wherein said temporally consecutive segments comprise temporally consecutive segments of calibration k-space line data, and
wherein said RF signal generator and said magnetic field gradient generator are configured to acquire said temporally consecutive segments using a parallel imaging technique.
11. The system according to claim 10 , wherein
said RF signal generator and said magnetic field gradient generator are further configured to acquire additional temporally consecutive segments of calibration k-space line data of successive individual image slices.
12. The system according to claim 10 , wherein
said RF signal generator and said magnetic field gradient generator are further configured to acquire additional temporally consecutive segments of calibration k-space line data of successive individual image slices.
13. The system according to claim 11 , wherein
wherein said parallel imaging technique is a GRAPPA (Generalized Autocalibrating Partially Parallel Acquisition) accelerated parallel imaging technique, and
wherein said calibration k-space line data comprises auto-calibration k-space line data of the GRAPPA accelerated parallel imaging technique.
14. The system according to claim 11 , wherein
said temporally consecutive segments of calibration k-space line data are temporally consecutive for said individual image slice and interleaved in k-space.
15. A system for accelerated segmented magnetic resonance (MR) image data acquisition, comprising:
an RF (Radio Frequency) signal generator for generating RF excitation pulses in anatomy and enabling subsequent acquisition of associated RF echo data; and
a magnetic field gradient generator for generating magnetic field gradients for anatomical volume selection, phase encoding and readout RF data acquisition in a three dimensional (3D) anatomical volume,
wherein said RF signal generator and said magnetic field gradient generator are configured to acquire temporally consecutive segments of k-space line data representative of a first individual image slice using a gradient echo technique comprising a substantially identical flip angle value for acquisition of said temporally consecutive segments of k-space line data representative of the same individual slice before acquiring temporally consecutive segments of k-space line data representative of a second individual image slice.
16. The system according to claim 15 ,
wherein said temporally consecutive segments comprise temporally consecutive segments of calibration k-space line data, and
wherein said RF signal generator and said magnetic field gradient generator are further configured to acquire said temporally consecutive segments using a parallel imaging technique.
17. The system according to claim 16 , wherein
said RF signal generator and said magnetic field gradient generator are further configured to acquire additional temporally consecutive segments of calibration k-space line data representative of successive individual image slices.
18. A method for accelerated segmented magnetic resonance (MR) image data acquisition, comprising:
acquiring temporally consecutive segments of k-space line data representative of a first individual image slice using a gradient echo technique by adaptively varying RF excitation pulse flip angles between acquisition of said temporally consecutive segments before acquiring temporally consecutive segments of k-space line data representative of a second individual image slice,
wherein said acquiring is performed using an RF (Radio Frequency) signal generator configured to generate RF excitation pulses in anatomy and enable subsequent acquisition of associated RF echo data, and further using a magnetic field gradient generator configured to generate magnetic field gradients for anatomical volume selection, phase encoding and readout RF data acquisition in a three dimensional (3D) anatomical volume, and
wherein the adaptive variation of the RF excitation pulse flip angles is calculated to provide an equal magnetization across segments.
19. The method according to claim 18 ,
wherein said temporally consecutive segments comprise temporally consecutive segments of calibration k-space line data, and
wherein said RF signal generator and said magnetic field gradient generator acquire said temporally consecutive segments using a parallel imaging technique.
20. The method according to claim 19 , further comprising:
acquiring additional temporally consecutive segments of calibration k-space line data representative of successive individual image slices using said RF (Radio Frequency) signal generator and said magnetic field gradient generator.