Characterization of respiratory motion in the abdomen using a 4D MRI technique with 3D radial sampling and respiratory self-gating

Patent metadata

Field	Value
Publication number	US-10925510-B2
Application number	US-201514707647-A
Country	US
Kind code	B2
Filing date	May 8, 2015
Priority date	May 8, 2015
Publication date	Feb 23, 2021
Grant date	Feb 23, 2021

Abstract

Magnetic resonance imaging utilizing a continuous spoiled gradient echo sequence with 3D radial trajectory and 1D self-gating for respiratory motion detection can be used to characterize respirator motion in the abdomen. The resulting image data is acquired and is retrospectively sorted into different respiratory phases based on their temporal locations within a respiratory cycle, and each phase is reconstructed via a self-calibrating conjugate gradient sensitivity encoding (CG-SENSE) program.

First claim

What is claimed is:

1. A method for producing a set of images that depict motion of a tumor and/or non-tumor tissue utilizing magnetic resonance imaging (MRI), comprising:
utilizing an MRI machine to apply a spoiled gradient echo sequence with a three-dimensional (3D) radial sampling k-space trajectory and one-dimensional (1D) projection-based self-gating (SG) to a volume of interest (VOI) comprising (i) a tumor, (ii) a portion of the tumor, (iii) an organ, or (iv) a portion of the organ within a subject during a plurality of respiratory cycles;
acquiring magnetic resonance (MR) data from the subject, wherein the MR data comprises a plurality of sets of imaging lines and a plurality of sets of SG lines, each of the plurality of sets of SG lines including at least a first SG line and a second SG line, and wherein (a) each respective set of imaging lines of the plurality of imaging lines is preceded by a respective one of the plurality of sets of SG lines that serve as a motion stamp for the respective set of imaging lines of the plurality of sets of imaging lines that the respective one of the plurality of sets of SG lines precede, and (b) a Fourier Transform of the SG lines is sensitive to respiratory-induced motion in a specific direction of the tumor, the portion of the tumor, the organ, or the portion of the organ;
taking the Fourier Transform of only the second SG line of each of the plurality of sets of SG lines to form a multi-channel projection profile time series;
deriving a respiratory curve comprising a plurality of time points by performing a principal component analysis (PCA) on the multi-channel projection profile time series and identifying an appropriate component of the multi-channel projection profile series that has a major Fourier mode matching a typical respiratory frequency, wherein each time point on the respiratory curve corresponds to the second SG line of each respective one of the plurality of sets of SG lines and provides an index for a position of the respective set of imaging lines following each respective one of the plurality of sets of SG lines along the specific direction;
applying band-pass filtering and peak detection to the respiratory curve to identify a plurality of respiratory cycles of the respiratory curve;
discarding any of the plurality of respiratory cycles having an abnormal duration or an outlier end-expiratory location;
sorting each remaining cycle of the plurality of respiratory cycles into a plurality of respiratory phases, based on the relative temporal locations or relative spatial positions indicated by the second SG line of the respective one of the plurality of sets of SG lines preceding each of the plurality of sets of imaging lines within the plurality of respiratory cycles; and
reconstructing an image for at least a first respiratory phase of the plurality of respiratory phases and a second respiratory phase of the plurality of respiratory phases by applying a conjugate gradient (CG) sensitivity encoding (SENSE) scheme with self-sensitivity calibration, thereby producing at least two images that collectively depict motion of the tumor and/or non-tumor tissue.

2. The method of claim 1 , wherein the 3D radial sampling k-space is filled by utilizing 2D golden means ordering.

3. The method of claim 1 , wherein the first SG line and the second SG line that precede each of the plurality of sets of imaging lines are both superior-inferior (SI) readout lines.

4. The method of claim 3 , wherein each of the plurality of sets of imaging lines comprises a number of imaging lines depending on a desired temporal resolution.

5. The method of claim 3 , wherein the Fourier Transform of the second SG line of each of the plurality of sets of SG lines is sensitive to respiratory organ motion in an SI direction.

6. The method of claim 5 , wherein each time point on the respiratory curve provides an index for the SI position of the respective set of imaging lines following each respective one of the plurality of sets of SG lines.

7. The method of claim 6 , wherein peaks of the respiratory curve correspond to end-expiration.

8. The method of claim 1 , wherein the subject is breathing irregularly or deeply.

9. The method of claim 1 , wherein the tumor is a cancerous tumor.

10. The method of claim 1 , wherein each of the plurality of sets of imaging lines includes at least one imaging line that extends along three dimensions in k-space.

11. The method of claim 1 , wherein the first SG line and the second SG line of each of the plurality of sets of SG lines are identical to each other.

12. A magnetic resonance imaging system, comprising:
a magnet operable to provide a magnetic field;
a transmitter operable to transmit to a region within the magnetic field;
a receiver operable to receive a magnetic resonance signal from the region;
a processor operable to control the transmitter and the receiver; and
a non-transitory machine readable medium with instructions embedded thereon that when executed by the processor or a computing machine capable of communicating electronically with the processor cause the processor to direct the transmitter and receiver to execute a sequence, comprising:
applying a spoiled gradient echo sequence with a three-dimensional (3D) radial sampling k-space trajectory and one-dimensional (1D) projection-based self-gating (SG) to a volume of interest (VOI) comprising (i) a tumor, (ii) a portion of the tumor, (iii) an organ, or (iv) a portion of the organ within a subject during a plurality of respiratory cycles;
acquiring magnetic resonance (MR) data from the subject, wherein the magnetic resonance data comprises a plurality of sets of imaging lines and a plurality of sets of SG lines, each of the plurality of sets of SG lines including at least first SG line and a second SG line, and wherein (i) each respective set of imaging lines of the plurality of imaging lines is preceded by a respective one of the plurality of sets of SG lines that serve as a motion stamp for the respective set of imaging lines of the plurality of imaging lines that the respective one of the plurality of sets of SG lines precede, and (ii) a Fourier Transform of the SG lines is sensitive to respiratory-induced motion in a specific direction of the tumor, the portion of the tumor, the organ, or the portion of the organ;
taking the Fourier Transform of only the second SG line of each of the plurality of sets of SG lines to form a multi-channel projection profile time series;
deriving a respiratory curve comprising a plurality of time points by performing a principal component analysis (PCA) on the multi-channel projection profile time series and identifying an appropriate component of the multi-channel projection profile series that has a major Fourier mode matching a typical respiratory frequency, wherein each time point on the respiratory curve corresponds to the second SG line of each respective one of the plurality of sets of SG lines and provides an index for a position of the respective set of imaging lines following each respective one of the plurality of sets of SG lines along the specific direction;
applying band-pass filtering and peak detection to the respiratory curve to identify a plurality of respiratory cycles of the respiratory curve;
discarding any of the plurality of respiratory cycles having an abnormal duration or an outlier end-expiratory location;
sorting each remaining cycle of the plurality of respiratory cycles into a plurality of respiratory phases, based on the relative temporal locations or relative spatial positions indicated by the second SG line of the respective one of the plurality of sets of SG lines preceding each of

Assignees

• Cedars Sinai Medical Center

Inventors

• Fan Zhaoyang
• Pang Jianing
• Deng Zixin
• Li Debiao

Classifications

• A61B5/055 Primary

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

• G01R33/56509

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

• G01R33/4826

  in three dimensions · CPC title

• G01R33/5676

  Gating or triggering based on an MR signal, e.g. involving one or more navigator echoes for motion monitoring and correction · CPC title

• A61B5/7257

  using Fourier transforms · CPC title