Corrected multiple-slice magnetic resonance imaging

Patent metadata

Field	Value
Publication number	US-2016252596-A1
Application number	US-201415027283-A
Country	US
Kind code	A1
Filing date	Sep 25, 2014
Priority date	Oct 8, 2013
Publication date	Sep 1, 2016
Grant date	—

Abstract

The invention provides for a magnetic resonance imaging system ( 100 ) for acquiring magnetic resonance data ( 142, 148, 158 ) with a pulse sequence ( 140 ) for multiple slice acquisition performed over multiple repetition cycles. The magnetic resonance imaging system further comprises a processor ( 540 ) for controlling the magnetic resonance imaging system. The execution of the instructions cause the processor to: acquire ( 200 ) a first slice group ( 142 ) of the magnetic resonance data during a first repetition cycle; extract ( 202 ) first central k-space data ( 144 ) from the first slice group; reconstruct ( 204 ) first navigator data ( 146 ) using the first central k-space data. Execution of the instructions causes the processor to repeatedly: acquire ( 206 ) a subsequent slice group ( 148 ) of the magnetic resonance data during a subsequent repetition cycle; extract ( 208 ) subsequent central k-space data ( 150 ) from the subsequent slice group; reconstruct ( 210 ) subsequent navigator data ( 152 ) using the subsequent central k-space data; determining ( 212 ) a mapping ( 154 ) from the first navigator data to the subsequent navigator data; and correct ( 214 ) the acquisition of a next slice group of the magnetic resonance data using the mapping.

First claim

1 . A magnetic resonance imaging system for acquiring magnetic resonance data from a subject within an imaging zone, wherein the magnetic resonance imaging system comprises:
a memory configured to store machine executable instructions and pulse sequence data being descriptive of a pulse sequence for controlling the magnetic resonance imaging system to acquire the magnetic resonance data, wherein the pulse sequence data controls the magnetic resonance imaging system to acquire the magnetic resonance data as a multiple slice acquisition performed over multiple repetition cycles; and a processor for controlling the magnetic resonance imaging system, wherein execution of the instructions cause the processor to:
acquire a first slice group of the magnetic resonance data during a first repetition cycle using the pulse sequence data;
extract first central k-space data from the first slice group;
reconstruct first navigator data as a first three-dimensional navigator in image space using the first central k-space data;
wherein execution of the instructions causes the processor to repeatedly:
acquire a subsequent slice group of the magnetic resonance data during a subsequent repetition cycle using the pulse sequence data;
extract subsequent central k-space data from the subsequent slice group;
reconstruct subsequent navigator data as a subsequent three-dimensional navigator in image space using the subsequent central k-space data;
determining a mapping from the first navigator data to the subsequent navigator data by performing a three-dimensional transformation between the first navigator data and the subsequent navigator data; and
correct the acquisition of a next slice group of the magnetic resonance data using the mapping.

2 . The magnetic resonance imaging system of claim 1 , wherein the magnetic resonance data comprises multiple slices, and wherein the correction of the acquisition of the next slice group of the magnetic resonance data with the mapping corrects for in-plane rigid body motion of the subject within each of the multiple slices and for through-plane rigid body motion between the multiple slices.

3 . The magnetic resonance imaging system of claim 1 , wherein execution of the instructions causes the processor to: calculate scan parameter adjustments using the mapping, wherein the correction of the acquisition of the next slice group of the magnetic resonance data using the mapping is at least partially performed by modifying the acquisition of the next slice group of the magnetic resonance data with the scan parameter adjustments.

4 . The magnetic resonance imaging system of claim 1 , wherein execution of the instructions further causes the processor to:
determine if the mapping has a transformation above a predetermined deletion threshold, wherein the correction of the acquisition of the next slice group of the magnetic resonance data using the rigid body transformation is at least partially performed by deleting the subsequent slice group of the magnetic resonance data from the magnetic resonance data.

5 . The magnetic resonance imaging system of claim 1 , wherein execution of the instructions further causes the processor to: determine if the mapping has a transformation above a predetermined reacquisition threshold, wherein the correction of the acquisition of the next slice group of the magnetic resonance data using the rigid body transformation is at least partially performed by re-acquiring the subsequent slice group of the magnetic resonance data.

6 . The magnetic resonance imaging system of claim 1 , wherein the pulse sequence data is operable to cause the magnetic resonance imaging system to acquire the magnetic resonance data without a gap between the multiple slices, wherein execution of the instructions further causes the processor to reconstruct a magnetic resonance image using the magnetic resonance data and the rigid body transformation by iteratively correcting the location of the subsequent slice group of the magnetic resonance data.

7 . (canceled)

8 . The magnetic resonance imaging system of claim 1 , wherein the mapping is any one of the following: a rigid body transformation; a deformable body transformation; a rigid body transformation for a region of interest; and a rigid body transformation for the region of interest with a deformable body transformation for a surrounding region.

9 . The magnetic resonance imaging system of claim 1 , wherein the magnetic resonance imaging system comprises a multi-element radio frequency coil for acquiring the magnetic resonance data, wherein the pulse sequence is a parallel imaging technique, wherein execution of the instructions further causes the processor to:
receive a set of coil sensitivities for the multi-element radio frequency coil; unfold the first three-dimensional navigator image using the set of coil sensitivities; and unfold the subsequent three-dimensional navigator image using the set of coil sensitivities.

10 . The magnetic resonance imaging system of claim 8 , wherein execution of the instructions causes the processor to:
calculate a first two-dimensional image by slicing the first three-dimensional navigator image along a first plane; calculate a subsequent two-dimensional image by slicing the subsequent three-dimensional navigator image along a second plane, wherein the location of the second plane is determined by applying the mapping to the first plane; calculate an in-plane deformable body transformation between the first two-dimensional image and the subsequent two-dimensional image; and reacquiring or deleting a slice portion of the subsequent slice group of the magnetic resonance data if the deformable body transformation indicates motion of the subject beyond a predetermined amount.

11 . The magnetic resonance imaging system of claim 1 , wherein the first navigator data is a first k-space navigator, wherein the second navigator data is a second k-space navigator.

12 . The magnetic resonance imaging system of claim 1 , wherein the pulse sequence data comprises commands for performing any one of the following magnetic resonance imaging techniques: PROPELLER, radial Turbo Spin Echo, selected spiral Turbo Spin Echo, and Turbo Field Echo.

13 . The magnetic resonance imaging system of claim 1 , wherein execution of the instructions cause the processor to replace the first navigator data with the subsequent navigator data after determining the mapping.

14 . A computer program product comprising machine executable instructions stored on a non-transitory computer readable medium for execution by a processor controlling a magnetic resonance imaging system for acquiring magnetic resonance data from a subject within an imaging zone, wherein the magnetic resonance imaging system comprises a memory for storing pulse sequence data, wherein the pulse sequence data comprises instructions for controlling the magnetic resonance imaging system to acquire the magnetic resonance data, wherein the pulse sequence data controls the magnetic resonance imaging system to acquire the magnetic resonance data as a multiple slice acquisition performed over multiple repetition cycles, wherein execution of the instructions cause the processor to:
acquire a first slice group of the magnetic resonance data during a first repetition cycle using the pulse sequence data; extract first central k-space data from the first slice group; reconstruct first navigator data as a first three-dimensional navigator in image space using the first central k-space data; wherein execution of the instructions causes the processor to repeatedly: acquire a subsequent slic

Assignees

• Koninklijke Philips Nv

Inventors

• Nielsen Tim
• Boernert Jr Peter

Classifications

• G01R33/4824

  using a non-Cartesian trajectory · CPC title

• G01R33/482

  using a Cartesian trajectory · CPC title

• G01R33/5617

  using RF refocusing, e.g. RARE · CPC title

• G01R33/56509

  due to motion, displacement or flow, e.g. gradient moment nulling (G01R33/567 takes precedence) · CPC title

• G01R33/4835 Primary

  of multiple slices · CPC title