System and method for out-of-view artifact suppression for magnetic resonance fingerprinting

1. A method for magnetic resonance fingerprinting with out-of-view artifact suppression, the method comprising:

acquiring MRF data from a region of interest in a subject using the MRI system, wherein the MRF data is acquired using a non-Cartesian, variable density sampling trajectory and wherein the MRF data includes data from within a desired field-of-view and data from outside the desired field-of-view;

generating a set of coil images based on the MRF data with a field-of-view larger than the desired field-of-view;

determining a noise covariance based on the MRF data from outside the desired field-of-view;

generating a coil combined image using an adaptive coil combination determined based on the noise covariance;

applying the adaptive coil combination to the MRF data to grid each frame of the MRF data and generate MRF data with out-of-view artifact suppression;

comparing the MRF data with out-of-view artifact suppression to an MRF dictionary to identify at least one property of the MRF data; and

generating a report indicating the at least one property of the MRF data.

2. The method according to claim 1 , wherein the set of coil images is a time-averaged set of coil images.

3. The method according to claim 1 , wherein the coil combined image is given by:

I ( x,y )=Σ j=1 N m j * C j(x,y) .

4. The method according to claim 3 , wherein the coil combination m j is determined using the eigenvalue decomposition of the matrix P=R n −1 R S , where R S is the signal coil covariance matrix and R n is the noise coil covariance.

5. The method according to claim 1 , wherein applying the adaptive coil combination to the MRF data may be given by:

I ( x,y,t )=Σ j=1 N m j *C j ( x,y,t ).

6. The method according to claim 1 , wherein the set of MRF data is acquired using a parallel receive coil array.

7. A magnetic resonance fingerprinting (MRF) system comprising:

a magnet system configured to generate a polarizing magnetic field about at least a portion of a subject;

a magnetic gradient system including a plurality of magnetic gradient coils configured to apply at least one magnetic gradient field to the polarizing magnetic field;

a radio frequency (RF) system configured to apply an RF field to the subject and to receive magnetic resonance signals from the subject using a coil array; and

a computer system programmed to:

acquire MRF data from a region of interest in a subject using the MRI system, wherein the MRF data is acquired using a non-Cartesian, variable density sampling trajectory and wherein the MRF data includes data from within a desired field-of-view and data from outside the desired field-of-view;

generate a set of coil images based on the MRF data with a field-of-view larger than the desired field-of-view;

determine a noise covariance based on the MRF data from outside the desired field-of-view;

generate a coil combined image using an adaptive coil combination determined based on the noise covariance;

apply the adaptive coil combination to the MRF data to grid each frame of the MRF data and generate MRF data with out-of-view artifact suppression;

compare the MRF data with out-of-view artifact suppression to an MRF dictionary to identify at least one property of the MRF data; and

generate a report indicating the at least one property of the MRF data.

8. The system according to claim 7 , wherein the set of coil images is a time-averaged set of coil images.

9. The system according to claim 7 , wherein the coil combined image is given by:

I ( x,y )=Σ j=1 N m j * C j ( x,y ).

10. The system according to claim 9 , wherein the coil combination m j is determined using the eigenvalue decomposition of the matrix P=R n −1 R S , where R S is the signal coil covariance matrix and R n is the noise coil covariance.

11. The system according to claim 7 , wherein applying the adaptive coil combination to the MRF data may be given by:

I ( x,y,t )=Σ j=1 N m j *C j ( x,y,t ).

12. The system according to claim 7 , wherein the RF system includes a parallel receive coil array and the MRF data is acquired using the parallel receive coil array.