Recordation of a magnetic resonance data set

Patent metadata

Field	Value
Publication number	US-11054494-B2
Application number	US-201916513843-A
Country	US
Kind code	B2
Filing date	Jul 17, 2019
Priority date	Jul 17, 2018
Publication date	Jul 6, 2021
Grant date	Jul 6, 2021

Abstract

Techniques are disclosed related to recording a magnetic resonance image data set of a region of a patient with a magnetic resonance device using a multislice imaging technique. The multislice technique may be applied simultaneously with at least partial undersampling in a slice plane. The magnetic resonance data may be read out from a set of excited slices simultaneously and, by means of a slice separation algorithm that is calibrated using reference data recorded in a separate reference scan, may be allocated to the simultaneously read-out slices. Subsequently, an undersampling algorithm compensating for the undersampling in the slice plane may be applied to the undersampled magnetic resonance data of the individual slices.

First claim

What is claimed is:

1. A computer-implemented method for recording, using a magnetic resonance device, a magnetic resonance image data set of a region of a patient, the method comprising:
operating a magnetic resonance data acquisition scanner to execute a multislice imaging algorithm using simultaneous at least partial undersampling in a slice plane to read out magnetic resonance data simultaneously from a plurality of excited slices, the magnetic resonance data being separated into at least two portions, each respective one of the at least two portions being associated with a respective subregion of sampled k-space in the slice plane of the magnetic resonance data having a different fixed degree of sampling;
calibrating, via the magnetic resonance data acquisition scanner, a slice separation algorithm using reference data that is recorded in a separate reference scan;
separately executing, via the magnetic resonance data acquisition scanner, for each respective one of the at least two portions of the magnetic resonance data associated with a respective subregion of the sampled k-space, the calibrated slice separation algorithm to the simultaneously read out plurality of excited slices to generate respective slice-separated portions, the calibrated slice separation algorithm utilizing a different respective slice separation kernel for each respective one of the at least two portions of the magnetic resonance data;
executing, via the magnetic resonance data acquisition scanner, an undersampling algorithm to undersampled magnetic resonance data associated with the slice-separated portions having a fixed degree of sampling associated with undersampling to compensate for the at least partial undersampling in the slice plane; and
recombining slice-by-slice, via the magnetic resonance data acquisition scanner after compensation of the undersampling in the slice plane, the respective slice-separated portions of the magnetic resonance data to generate the magnetic resonance image data set.

2. The method as claimed in claim 1 , wherein the reference data is recorded with a complete sampling of k-space and by omitting part of the reference data to determine at least one slice separation kernel for the slice separation algorithm such that an artificial undersampling of the reference data corresponds to the undersampling of the respective one of the at least two portions of the magnetic resonance data for which the slice separation kernel is to be used.

3. The method as claimed in claim 2 , wherein each respective one of the at least two portions of the magnetic resonance data corresponds to a different degree of sampling, and
wherein at least one corresponding slice separation kernel is determined for each respective one of the at least two portions of the magnetic resonance data.

4. The method as claimed in claim 1 , wherein each respective one of the at least two portions of the magnetic resonance data has the same degree of sampling.

5. The method as claimed in claim 4 , wherein the reference data is recorded with the same degree of sampling as each respective one of the at least two portions of the magnetic resonance data.

6. The method as claimed in claim 4 , wherein the at least two portions of the magnetic resonance data include a first portion associated with a first subregion of sampled k-space in the slice plane of the magnetic resonance data and a second portion associated with a second subregion of sampled k-space in the slice plane of the magnetic resonance data,
wherein upon complete sampling of the first subregion about k-space center and undersampling of the second subregion comprising remaining k-space, k-space lines are added from the first subregion to the second portion by continuing the sampling pattern of the second subregion, and
wherein the remaining magnetic resonance data of the first subregion having undersampling that corresponds to that of the second portion is further processed.

7. The method as claimed in claim 1 , wherein one of the at least two portions of the magnetic resonance data corresponding to a subregion of sampled k-space in the slice plane of the magnetic resonance data having a higher degree of sampling is used for calibrating the undersampling algorithm.

8. The method as claimed in claim 1 , wherein at least one completely sampled portion of the reference data is used for calibrating the undersampling algorithm.

9. The method as claimed in claim 1 , wherein the slice separation algorithm includes a slice Generalized Autocalibrating Partially Parallel Acquisitions (GRAPPA) algorithm.

10. The method as claimed in claim 1 , wherein the undersampling algorithm includes an in-plane Generalized Autocalibrating Partially Parallel Acquisitions (GRAPPA) algorithm.

11. The method as claimed in claim 1 , wherein the magnetic resonance data is generated using a blipped Controlled Aliasing in Parallel Imaging (CAIPI) technique as the multislice imaging technique.

12. The method as claimed in claim 1 , wherein the magnetic resonance data is generated using a magnetic resonance sequence that includes a turbospin echo (TSE) sequence.

13. A magnetic resonance device for recording a magnetic resonance image data set of a region of a patient, comprising:
a magnetic resonance data acquisition scanner;
a patient receiving space configured to receive the patient; and
a control device configured to operate the magnetic resonance data acquisition scanner to:
execute a multislice imaging algorithm using simultaneous at least partial undersampling in a slice plane to read out magnetic resonance data simultaneously from a plurality of excited slices, the magnetic resonance data being-separated into at least two portions, each respective one of the at least two portions being associated with a respective subregion of sampled k-space in the slice plane of the magnetic resonance data having a different fixed degree of sampling;
calibrate a slice separation algorithm using reference data that is recorded in a separate reference scan;
separately execute, for each respective one of the at least two portions of the magnetic resonance data associated with a respective subregion of the sampled k-space, the calibrated slice separation algorithm to the simultaneously read out plurality of excited slices to generate respective slice-separated portions, the calibrated slice separation algorithm utilizing a different slice separation kernel for each respective one of the at least two portions of the magnetic resonance data;
execute an undersampling algorithm to undersampled magnetic resonance data associated with the slice-separated portions having a fixed degree of sampling associated with undersampling to compensate for the at least partial undersampling in the slice plane; and
recombine, slice-by-slice after compensation of the undersampling in the slice plane, the respective slice-separated portions of the magnetic resonance data to generate the magnetic resonance image data set.

14. The magnetic resonance device as claimed in claim 13 , wherein the control device is configured to operate the magnetic resonance data acquisition scanner to record the reference data with a complete sampling of k-space and by omitting part of the reference data to determine at least one slice separation kernel for the slice separation algorithm such that an artificial undersampling of the reference data corresponds to the undersampling of the respective one of the at least two portions of the magnetic resonance data for which the slice separation kernel is to be used.

15. The magnetic resonance device as claimed in claim 14 , wherei

Assignees

• Siemens Healthcare Gmbh

Inventors

• Zeller Mario
• Carinci Flavio
• Paul Dominik

Classifications

• G06T12/00

  Tomographic reconstruction from projections · CPC title

• A61B5/055

  involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging · CPC title

• G06T5/50

  using two or more images, e.g. averaging or subtraction · CPC title

• A61B5/0035

  adapted for acquisition of images from more than one imaging mode, e.g. combining MRI and optical tomography · CPC title

• G01R33/286

  involving passive visualization of interventional instruments, i.e. making the instrument visible as part of the normal MR process · CPC title