# US 10,481,231 B2 · Magnetic resonance imaging apparatus and image generation method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,481,231 B2 - Document ID: US10481231B2 - Status: Granted - Kind: B2 - Application number: 15/342,576 - Filed: 2016-11-03 - Published: 2017-05-11 - Granted: 2019-11-19 - Earliest claimed: 2015-11-06 - Assignees: Canon Medical Systems Corporation - Applicants: Toshiba Medical Systems Corporation - Inventors: Hidenori Takeshima; Masao Yui; Takashi Shigeta - Web page: https://patentgrep.com/patent/US10481231B2 ## CPC - G01R 33/4818: {MR characterised by data acquisition along a specific k-space trajectory or by the temporal order of k-space coverage, e.g. centric or segmented coverage of k-space} - G01R 33/50: based on the determination of relaxation times {, e.g. T1 measurement by IR sequences; T2 measurement by multiple-echo sequences} - 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 33/5611: {Parallel magnetic resonance imaging, e.g. sensitivity encoding [SENSE], simultaneous acquisition of spatial harmonics [SMASH], unaliasing by Fourier encoding of the overlaps using the temporal dimension [UNFOLD], k-t-broad-use linear acquisition speed-up technique [k-t-BLAST], k-t-SENSE (structural details of arrays of sub-coils G01R33/3415)} - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract A magnetic resonance imaging apparatus according to an embodiment includes first processing circuitry and second processing circuitry. The first processing circuitry executes a pulse sequence in a acquisition pattern set such that sampling densities of a plurality of pieces of k space data are made different in accordance with a predetermined imaging parameter when the pieces of k space data having different values of the imaging parameter are acquired while changing the values of the imaging parameter. The second processing circuitry generates an image based on the pieces of k space data. ## Claims ### Claim 1 A magnetic resonance imaging apparatus comprising: first processing circuitry configured to execute a pulse sequence in an acquisition pattern set such that reduction factors in a plurality of pieces of k space data are made different in accordance with a predetermined imaging parameter when the pieces of k space data having different values of the imaging parameter are acquired while changing the values of the imaging parameter; and second processing circuitry configured to generate an image based on the pieces of k space data, wherein when the imaging parameter is included in a first range, the first processing circuitry acquires the pieces of k space data in a first region including a center in a k space with a first reduction factor and acquires the pieces of k space data in a second region that differs from the first region with a second reduction factor that differs from the first reduction factor, and when the imaging parameter is included in a second range that differs from the first range, the first processing circuitry acquires the pieces of k space data in the first region with a reduction factor higher than the first reduction factor and acquires the pieces of k space data in the second region with a reduction factor lower than the second reduction factor. ### Claim 2 (depends on 1) The magnetic resonance imaging apparatus according to claim 1, wherein the second processing circuitry generates a mapping image for the imaging parameter. ### Claim 3 (depends on 1) The magnetic resonance imaging apparatus according to claim 1, wherein the imaging parameter is inversion time (TI), the first processing circuitry acquires the pieces of k space data by controlling execution of the pulse sequence including pulse control for emitting radio frequency (RF) pulses of greater than 90 degrees, and the second processing circuitry generates a T1 mapping image based on the pieces of k space data. ### Claim 4 (depends on 1) The magnetic resonance imaging apparatus according to claim 1, wherein the imaging parameter is echo time (TE), the first processing circuitry acquires the pieces of k space data by controlling execution of the pulse sequence including pulse control for acquiring multi echo, and the second processing circuitry generates a T2 mapping image based on the pieces of k space data. ### Claim 5 (depends on 1) The magnetic resonance imaging apparatus according to claim 1, wherein the imaging parameter is spin lock time (TSL), the first processing circuitry acquires the pieces of k space data by controlling execution of the pulse sequence including pulse control for emitting spin lock pulses, and the second processing circuitry generates a T1ρ mapping image based on the pieces of k space data. ### Claim 6 (depends on 1) The magnetic resonance imaging apparatus according to claim 1, wherein the first range is a range in which degree of variation in a corresponding pixel value is equal to or higher than a predetermined value and the second range is a range in which the degree of the variation in the corresponding pixel value is lower than the predetermined value. ### Claim 7 (depends on 1) The magnetic resonance imaging apparatus according to claim 1, wherein the second processing circuitry generates, in at least one region of the first region and the second region, first k space data at a k-space position at which k-space data is not acquired, using second k-space data at the k-space position, the first k-space data and the second k-space data corresponding to a different value of the imaging parameter. ### Claim 8 (depends on 1) The magnetic resonance imaging apparatus according to claim 1, wherein the second processing circuitry generates, in at least one region of the first region and the second region, first k space data at a first k-space position at which k-space data is not acquired, using second k-space data at a second k-space position that is within a predetermined range from the first k-space position, the first k-space data and the second k-space data corresponding to a different value of the imaging parameter. ### Claim 9 (depends on 1) The magnetic resonance imaging apparatus according to claim 1, wherein the first processing circuitry acquires the pieces of k space data in the first region with the first reduction factor and acquires the pieces of k space data in the second region with the second reduction factor, and then acquires the pieces of k space data in the first region with a reduction factor higher than the first reduction factor and acquires the pieces of k space data in the second region with a reduction factor lower than the second reduction factor. ### Claim 10 (depends on 1) The magnetic resonance imaging apparatus according to claim 1, wherein the first processing circuitry executes the pulse sequence in the acquisition pattern set such that a sampling density over the entire k space data is a predetermined value. ### Claim 11 An image generation method comprising: executing a pulse sequence in an acquisition pattern set such that reduction factors in a plurality of pieces of k space data are made different in accordance with a predetermined imaging parameter when the pieces of k space data having different values of the imaging parameter are acquired while changing the values of the imaging parameter; and generating an image based on the pieces of k space data, wherein when the imaging parameter is included in a first range, the method comprises: acquiring the pieces of k space data in a first region including a center in a k space with a first reduction factor, and acquiring the pieces of k space data in a second region that differs from the first region with a second reduction factor that differs from the first reduction factor; and when the imaging parameter is included in a second range that differs from the first range, the method comprises: acquiring the pieces of k space data in the first region with a reduction factor higher than the first reduction factor, and acquiring the pieces of k space data in the second region with a reduction factor lower than the second reduction factor.