# US 10,310,045 B2 · Method and apparatus for allocating acquired magnetic resonance data to respective movement states of the subject > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,310,045 B2 - Document ID: US10310045B2 - Status: Granted - Kind: B2 - Application number: 15/405,697 - Filed: 2017-01-13 - Published: 2017-07-13 - Granted: 2019-06-04 - Earliest claimed: 2016-01-13 - Assignees: Siemens Healthcare GmbH - Applicants: Siemens Healthcare GmbH - Inventors: Marcel Dominik Nickel - Web page: https://patentgrep.com/patent/US10310045B2 ## CPC - G01R 33/56509: {due to motion, displacement or flow, e.g. gradient moment nulling (G01R33/567 takes precedence)} - G01R 33/5608: {Data processing and visualization specially adapted for MR, e.g. for feature analysis and pattern recognition on the basis of measured MR data, segmentation of measured MR data, edge contour detection on the basis of measured MR data, for enhancing measured MR data in terms of signal-to-noise ratio by means of noise filtering or apodization, for enhancing measured MR data in terms of resolution by means for deblurring, windowing, zero filling, or generation of gray-scaled images, colour-coded images or images displaying vectors instead of pixels (image data processing or generation, in general G06T)} - G01R 33/56391: {involving motion of a part of the sample with respect to another part of the sample, e.g. MRI of active joint motion} - G01R 33/5676: {Gating or triggering based on an MR signal, e.g. involving one or more navigator echoes for motion monitoring and correction} - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract In a method and apparatus for allocating MR imaging signals from a person under examination to N different movement states that occur in the person under examination. MR signals are acquired for the creation of MR images that represent at least one region of the person under examination. A number of MR navigator data sets of the person under examination also are acquired. A cluster analysis is applied to the MR navigator data sets in order to identify similarities in the MR navigator data sets. Similar navigator data sets are allocated to a movement state of the person under examination, the multiple navigator data sets all being allocated respectively to one movement state of the N movement states. The MR imaging signals acquired thus can be allocated to the N movement states. ## Claims ### Claim 1 A method for acquiring magnetic resonance (MR) data, comprising: operating an MR data acquisition scanner to acquire sets of MR diagnostic data from a living subject that represent at least one region of the subject, said subject exhibiting N different movement states during acquisition of said sets of MR diagnostic data; also operating said MR data acquisition scanner to acquire a plurality of MR navigator data sets from the subject that are respectively associated with individual ones of said sets of MR diagnostic data; providing the acquired sets of MR diagnostic data and the acquired plurality of MR navigator data sets to a computer and, in said computer, applying a cluster analysis to said plurality of MR navigator data sets to identify similarities among the respective MR navigator data sets and to allocate similar MR navigator data sets to a respective movement state of said subject, among said N movement states, so that each MR navigator data set in said plurality of MR navigator data sets is respectively allocated to one of said N movement states; and in said computer, allocating the acquired sets of MR diagnostic data to the same respective N movement states to which the MR navigator data set associated therewith was allocated, and making the plurality of MR navigator data sets respectively allocated to movement states, and the sets of MR diagnostic data allocated to the N movement states, available from the computer in electronic form as a data file. ### Claim 2 (depends on 1) A method as claimed in claim 1 comprising associating the respective individual MR navigator data sets with individual ones of said sets of MR diagnostic data by operating said MR data acquisition scanner to acquire said MR navigator data sets respectively following radiation of a radio-frequency (RF) excitation pulse that is identical to an RF excitation pulse radiated for the acquisition of one of said MR diagnostic data sets. ### Claim 3 (depends on 1) A method as claimed in claim 1 comprising operating said MR data acquisition scanner to acquire said sets of MR diagnostic data from said region of the subject that comprises an excitation volume, and acquiring said plurality of MR navigator data sets from the same excitation volume. ### Claim 4 (depends on 1) A method as claimed in claim 1 wherein said N different movement states of the subject occur in a primary movement direction, and operating said MR data acquisition scanner to acquire said plurality of MR navigator data sets by activating a readout gradient in a readout direction that is parallel to said primary movement direction. ### Claim 5 (depends on 1) A method as claimed in claim 1 comprising entering the acquired sets of MR diagnostic data as raw data into a raw data memory at respective raw data points in said memory, and allocating said sets of MR diagnostic data to said N movement states by allocating each raw data point thereof to one of said N movement states. ### Claim 6 (depends on 1) A method as claimed in claim 1 comprising, in an image reconstruction computer having access to said data file, reconstructing an image of said region of the subject from said sets of MR diagnostic data by executing an iterative reconstruction algorithm with each state associated with said sets of MR diagnostic data being used as a dimension in said iterative reconstruction algorithm. ### Claim 7 (depends on 1) A method as claimed in claim 1 comprising, before executing said cluster analysis in said computer, implementing a pre-processing of said plurality of MR navigator data sets in said computer, said pre-processing comprising at least one of: subjecting respective MR navigator data sets, which are present as projections in a readout direction along which said plurality of MR navigator data sets were acquired, to a filtration in at least one direction selected from the group consisting of a direction representing a temporal sequence of said plurality of MR navigator data sets and said projection direction; implementing a principal component analysis on said plurality of MR navigator data sets; and implementing a singular value decomposition on said plurality of MR navigator data sets. ### Claim 8 (depends on 1) A method as claimed in claim 1 comprising: in a reconstruction computer having access to said data file, reconstructing an MR image of said region of the subject from said sets of MR diagnostic data by executing a reconstruction algorithm; and in said reconstruction algorithm, using the reconstructed MR image to check whether the allocation of the sets of MR diagnostic data to the N movement states is in need of adjustment, by selecting a representative MR image for each of said N movement states and comparing the respective representative MR images with the reconstructed MR images, and renewing allocation of the sets of MR diagnostic data to the N movement states with said comparison does not satisfy a predetermined comparison criterion. ### Claim 9 (depends on 1) A method as claimed in claim 1 wherein said plurality of MR navigator data sets are acquired in a temporal sequence, and comprising, in said computer, dividing said temporal sequence into a plurality of different time segments, and executing said cluster analysis, and allocating respective MR navigator data sets to said N movement states, in each of said time segments individually, and simultaneously minimizing differences between said N movement states between respective individual time segments. ### Claim 10 A magnetic resonance (MR) apparatus comprising: an MR data acquisition scanner; a computer configured to operate said MR data acquisition scanner to acquire sets of MR diagnostic data from a subject that represent at least one region of the subject, said subject exhibiting N different movement states during acquisition of said sets of MR diagnostic data; said computer being configured to also operate said MR data acquisition scanner to acquire a plurality of MR navigator data sets from the subject that are respectively associated with individual ones of said sets of MR diagnostic data; said computer being configured to receive the acquired sets of MR diagnostic data and the acquired plurality of MR navigator data sets and to execute a cluster analysis on said plurality of MR navigator data sets to identify similarities among the respective MR navigator data sets and to allocate similar MR navigator data sets to a respective movement state of said subject, among said N movement states, so that each MR navigator data set in said plurality of MR navigator data sets is respectively allocated to one of said N movement states; and said computer being configured to allocate the acquired sets of MR diagnostic data to the respective N movement states to which the MR navigator data set associated therewith was allocated, and to make the plurality of MR navigator data sets respectively allocated to movement states, and the sets of MR diagnostic data allocated to the N movement states, available from the computer in electronic form as a data file. ### Claim 11 (depends on 10) An apparatus as claimed in claim 10 wherein said computer is configured to associate the respective individual MR navigator data sets with individual ones of said sets of MR diagnostic data by operating said MR data acquisition scanner to acquire said MR navigator data sets respectively following radiation of a radio-frequency (RF) excitation pulse that is identical to an RF excitation pulse radiated for the acquisition of one of said sets of MR diagnostic data. ### Claim 12 (depends on 10) An apparatus as claimed in claim 10 wherein said computer is configured said MR data acquisition scanner to acquire said sets of MR diagnostic data from said region of the subject that comprises an excitation volume, and to acquire said plurality of MR navigator data sets from the same excitation volume. ### Claim 13 (depends on 10) An apparatus as claimed in claim 10 wherein said N different movement states of the subject occur in a primary movement direction, and wherein said computer is configured to operate said MR data acquisition scanner to acquire said plurality of MR navigator data sets by activating a readout gradient in a readout direction that is parallel to said primary movement direction. ### Claim 14 (depends on 10) An apparatus as claimed in claim 10 comprising a raw data memory, and wherein said computer is configured to enter the acquired sets of MR diagnostic data as raw data into a raw data memory at respective raw data points in said sets of memory, and to allocate said sets of MR diagnostic data to said N movement states by allocating each raw data point thereof to one of said N movement states. ### Claim 15 (depends on 10) An apparatus as claimed in claim 10 wherein said computer is configured to operate as an image reconstruction computer having access to said data file, and to reconstruct an image of said region of the subject from said sets of MR diagnostic data by executing an iterative reconstruction algorithm with each state associated with said sets of MR diagnostic data being used as a dimension in said iterative reconstruction algorithm. ### Claim 16 (depends on 10) An apparatus as claimed in claim 10 wherein said computer is configured to: operate as a reconstruction computer having access to said data file, to reconstruct MR images of said region of the subject from said sets of MR diagnostic data by executing a reconstruction algorithm; and in said reconstruction algorithm, use the reconstructed MR images to check whether the allocation of the sets of MR diagnostic data to the N movement states is in need of adjustment, by selecting a representative MR image for each of said N movement states and comparing the respective representative MR images with the reconstructed MR images, and renewing allocation of the sets of MR diagnostic data to the N movement states with said comparison does not satisfy a predetermined comparison criterion. ### Claim 17 (depends on 10) An apparatus as claimed in claim 10 wherein said computer is configured to operate said MR data acquisition scanner to acquire said plurality of MR navigator data sets in a temporal sequence, and to divide said temporal sequence into a plurality of different time segments, and to execute said cluster analysis, and allocate respective MR navigator data sets to said N movement states, in each of said time segments individually, and to simultaneously minimize differences between said N movement states between respective individual time segments. ### Claim 18 A method for acquiring magnetic resonance (MR) data from a living subject, comprising: operating an MR data acquisition scanner to acquire a plurality of MR navigator data sets from a subject, said subject exhibiting movement, exhibiting a primary movement direction, during acquisition of said MR navigator data sets; operating said MR data acquisition scanner to acquire said plurality of MR navigator data sets by radiating at least one radio-frequency (RF) excitation pulse that excites nuclear spins in at least one excitation volume of the subject and by activating a readout gradient in a readout direction that is parallel to said primary movement direction; also operating said MR data acquisition scanner to acquire MR signals from at least one region of the subject; and operating said MR data acquisition scanner to acquire said MR signals by radiating at least one RF excitation pulse, which is identical to said at least one RF excitation pulse used to acquire said MR navigator data sets, that excites at least one RF excitation volume in the subject, that is identical to the at least one RF excitation volume excited by the at least one RF excitation pulse for acquiring said MR navigator data sets, said at least one RF excitation volume from which said MR signals are acquired being comprised in said region of said subject. ### Claim 19 A magnetic resonance apparatus comprising: an MR data acquisition scanner; a computer configured to operate said MR data acquisition scanner to acquire a plurality of MR navigator data sets from a subject, said subject exhibiting movement, exhibiting a primary movement direction, during acquisition of said MR navigator data sets; a computer configured to operate said MR data acquisition scanner to acquire said plurality of MR navigator data sets by radiating at least one radio-frequency (RF) excitation pulse that excites nuclear spins in at least one excitation volume of the subject and by activating a readout gradient in a readout direction that is parallel to said primary movement direction; a computer configured to also operate said MR data acquisition scanner to acquire MR signals from at least one region of the subject; and a computer configured to operate said MR data acquisition scanner to acquire said MR signals by radiating at least one RF excitation pulse, which is identical to said at least one RF excitation pulse used to acquire said MR navigator data sets, that excites at least one RF excitation volume in the subject, that is identical to the at least one RF excitation volume excited by the at least one RF excitation pulse for acquiring said MR navigator data sets, said at least one RF excitation volume from which said MR signals are acquired being comprised in said region of said subject. ### Claim 20 A non-transitory, computer-readable data storage medium encoded with programming instructions, said storage medium being loaded into a computer system of a magnetic resonance (MR) apparatus that comprises an MR data acquisition scanner, said programming instructions causing said computer system to: operate said MR data acquisition scanner to acquire sets of MR diagnostic data from a living subject that represent at least one region of the subject, said subject exhibiting N different movement states during acquisition of said sets of MR diagnostic data; also operate said MR data acquisition scanner to acquire a plurality of MR navigator data sets from the subject that are respectively associated with individual ones of said sets of MR diagnostic data; receive the acquired sets of MR diagnostic data and the acquired plurality of MR navigator data sets and apply a cluster analysis to said plurality of MR navigator data sets to identify similarities among the respective MR navigator data sets and to allocate similar MR navigator data sets to a respective movement state of said subject, among said N movement states, so that each MR navigator data set in said plurality of MR navigator data sets is respectively allocated to one of said N movement states; and allocate the acquired sets of MR diagnostic data to the respective N movement states to which the MR navigator data set associated therewith was allocated, and make the plurality of MR navigator data sets respectively allocated to movement states, and the sets of MR diagnostic data allocated to the N movement states, available from the computer in electronic form as a data file. ### Claim 21 A non-transitory, computer-readable data storage medium encoded with programming instructions, said storage medium being loaded into a computer system of a magnetic resonance (MR) apparatus that comprises an MR data acquisition scanner, said programming instructions causing said computer system to: operate said MR data acquisition scanner to acquire a plurality of MR navigator data sets from a subject, said subject exhibiting movement, exhibiting a primary movement direction, during acquisition of said MR navigator data sets; operate said MR data acquisition scanner to acquire said plurality of MR navigator data sets by radiating at least one radio-frequency (RF) excitation pulse that excites nuclear spins in at least one excitation volume of the subject and by activating a readout gradient in a readout direction that is parallel to said primary movement direction; also operate said MR data acquisition scanner to acquire MR signals from at least one region of the subject; and operate said MR data acquisition scanner to acquire said MR signals by radiating at least one RF excitation pulse, which is identical to said at least one RF excitation pulse used to acquire said MR navigator data sets, that excites at least one RF excitation volume in the subject, that is identical to the at least one RF excitation volume excited by the at least one RF excitation pulse for acquiring said MR navigator data sets, said at least one RF excitation volume from which said MR signals are acquired being comprised in said region of said subject.