Quiet magnetic resonance angiographic imaging

1. A method for magnetic resonance (MR) angiographic imaging, comprising:

operating an MR scanner to execute a scan sequence in which nuclear spins in a subject situated in the MR scanner are prepared in a preparation region with preparation parameters and, after preparing said nuclear spins, MR image data are acquired at ultrashort echo times from a scan region of the subject, said MR image data representing an image of the scan region;

in a processor provided with said MR image data, accessing reference image data that represent a reference image of the scan region, and combining said MR image data with said reference image data to produce a resultant image; and

making the resultant image available in electronic form at an output of the processor, as a data file.

2. A method as claimed in claim 1 comprising operating said MR scanner in said scan sequence to activate a gradient pulse having a flat pulse plateau, and radiating a radio-frequency (RF) excitation pulse during said flat pulse plateau of said gradient pulse, and acquiring said MR image data as scanned k-space points of an electronic memory at which said MR image data are entered during said flat pulse plateau of said gradient pulse during a respective ultrashort echo time.

3. A method as claimed in claim 1 comprising selecting said scan sequence from the group consisting of zero TE, SWIFT, WASPI, and PETRA.

4. A method as claimed in claim 1 comprising operating said MR scanner in said scan sequence to acquire said MR image data in multiple acquisitions respectively occurring at predetermined points in time following the preparation of the nuclear spins with the preparation parameters, and entering said MR image data at respective k-space points in an electronic memory that correspond to each predetermined point in time.

5. A method as claimed in claim 1 comprising:

operating said MR scanner in said scan sequence to acquire a first subset of said MR image data and entering said first subset of said MR image data at k-space points in an electronic memory representing k-space, along a radial k-space trajectory in a first region of k-space;

operating said MR scanner in said scan sequence to acquire a second subset of said MR image data and to enter said second subset of MR image data into said electronic memory at k-space points along a Cartesian k-space trajectory in a second region of k-space, said second region containing the center of k-space and containing at least some k-space points that are not contained in said first region; and

in said processor, combining said first and second subsets of MR data respectively in said first and second regions of k-space to obtain a totality of said MR image data.

6. A method as claimed in claim 5 comprising operating said MR scanner in said scan sequence to:

enter said first subset of said MR data at n k-space points in said first region respectively at predetermined points in time following said preparation of said nuclear spins with said preparation parameters; and

enter said second subset of MR data at m k-space points in said second region of k-space at predetermined points in time following said preparation of said nuclear spins with said preparation parameters, wherein m is greater than n.

7. A method as claimed in claim 6 comprising combining said first and second subsets of MR image data respectively in said first and second image regions according to a sliding window segmentation scheme.

8. A method as claimed in claim 6 comprising combining MR image data in said first subset, which are situated at respective k-space points in said first region, with MR image data in said second subset, which are situated at respective k-space points in said second region that have a minimum temporal spacing with the respective k-space points of said MR image data in said first subset.

9. A method as claimed in claim 5 comprising entering said MR image data in said first subset in said first region along first, second and third successively acquired radially oriented arms of said radial k-space trajectory, with said third radially oriented arm being situated in k-space between said first radially oriented arm and said second radially oriented arm.

10. A method as claimed in claim 1 comprising operating said MR scanner in said scan sequence to acquire said MR image data in multiple acquisitions respectively occurring at predetermined points in time following the preparation of the nuclear spins with the preparation parameters, and entering said MR image data at respective k-space points in an electronic memory that correspond to each predetermined point in time, and wherein the preparation of said nuclear spins comprises multiple individual preparations each comprising radiating a radio-frequency preparation pulse, with the respective multiple acquisitions of said MR image data being interleaved with the respective multiple individual preparations.

11. A method as claimed in claim 1 comprising operating said MR scanner in said scan sequence to prepare said nuclear spins by radiating a radio-frequency preparation pulse that causes an inversion or a saturation of said nuclear spins in said preparation region.

12. A method as claimed in claim 1 comprising operating said MR scanner to execute a further scan sequence in which said nuclear spins are prepared in said preparation region with further preparation parameters, and acquiring said reference image data from said scan region in said further scan sequence also at ultrashort echo times.

13. A method as claimed in claim 1 comprising operating said MR scanner to execute said scan sequence a plurality of times, with said MR image data being obtained in each repetition of said scan sequence as an image domain projection of the scan region, with the respective image domain projections of said scan region being from respectively different directions, and, in said processor, combining said plurality of image domain projections to obtain a two-dimensional, slice-selective image of said scan region as said first image data.

14. A magnetic resonance (MR) apparatus for MR angiographic imaging, comprising:

an MR scanner;

a control computer configured to operate said MR scanner to execute a scan sequence in which nuclear spins in a subject situated in the MR scanner are prepared in a preparation region with preparation parameters and, after preparing said nuclear spins, to acquire MR image data at ultrashort echo times from a scan region of the subject, said MR image data representing an image of the scan region;

a processor provided with said MR image data, said processor being configured to access reference image data that represent a reference image of the scan region, and combining said MR image data with said reference image data to produce a resultant image; and

said processor being configured to make the resultant image available in electronic form at an output of the processor, as a data file.