# US 9,869,737 B2 · Methods and systems for accelerated MR imaging > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,869,737 B2 - Document ID: US9869737B2 - Status: Granted - Kind: B2 - Application number: 14/181,761 - Filed: 2014-02-17 - Published: 2014-09-04 - Granted: 2018-01-16 - Earliest claimed: 2013-03-04 - Assignees: Siemens Healthcare GmbH - Applicants: Siemens Healthcare GmbH - Inventors: John William Grinstead - Web page: https://patentgrep.com/patent/US9869737B2 ## CPC - G01R 33/4835: {of multiple slices} - G01R 33/50: based on the determination of relaxation times {, e.g. T1 measurement by IR sequences; T2 measurement by multiple-echo sequences} - G01R 33/5611: {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 method for operating a Magnetic Resonance (MR) imaging system that includes generating radio frequency (RF) excitation pulses in a volume of patient anatomy and generating slice select magnetic field gradients for phase encoding and readout RF data acquisition in the patient anatomy. The method further includes concurrently acquiring T1 map image data of slices of an image by: (i) acquiring image calibration data using a pre-scan sequence; (ii) inverting a longitudinal magnetization in the volume of patient anatomy using a non-selective inversion recovery pulse; (iii) applying an excitation RF pulse to different slices in the volume of patient anatomy to rotate a portion of the longitudinal magnetization in a transverse direction; (iv) sampling individual slice image data of the slices in response to applying the excitation RF pulse; and (v) separating the concurrently acquired T1 map image into separate slices. ## Claims ### Claim 1 A method for operating a Magnetic Resonance (MR) imaging system, the method comprising: generating radio frequency (RF) excitation pulses in a volume of patient anatomy to provide subsequent acquisition of associated RF echo data; generating slice select magnetic field gradients for phase encoding and readout RF data acquisition in the patient anatomy; concurrently acquiring T1 map image data of a plurality of two dimensional slices of an image by an acquisition process comprising: (i) acquiring image calibration data using a pre-scan sequence; (ii) inverting a longitudinal magnetization in the volume of patient anatomy using a non-selective inversion recovery pulse; (iii) applying an excitation RF pulse to a plurality of different two dimensional slices in the volume of patient anatomy to rotate a portion of the longitudinal magnetization in a transverse direction; (iv) sampling individual slice image data of the plurality of two dimensional slices in response to applying the excitation RF pulse; and (v) separating the concurrently acquired T1 map image into separate slices. ### Claim 2 (depends on 1) The method according to claim 1, wherein acquiring the image calibration data using the pre-scan sequence further comprises acquiring each slice separately to estimate a k-space data kernel that separates the concurrently acquired T1 map image data into the separate slices. ### Claim 3 (depends on 2) The method according to claim 2, wherein the T1 map image data is acquired within the volume of anatomy during individual TI times for a plurality of successive TI times during inversion recovery time of the volume of anatomy to provide image data representing a plurality of successive images of an individual slice during the inversion recovery time. ### Claim 4 (depends on 3) The method according to claim 3, further comprising: processing individual luminance data values of an individual pixel location or a combination of luminance data values over a collection of pixel locations occurring within the plurality of successive images of the individual slice; and providing a composite individual pixel luminance value and a composite T1 map for the individual slice. ### Claim 5 (depends on 1) The method according to claim 1, further comprising concurrently acquiring the T1 map image data in response to a signal indicating start of introduction of contrast agent into a patient vessel. ### Claim 6 (depends on 1) The method according to claim 1, further comprising generating a display image showing images representing individual slices of said plurality of slices aligned with a common timeline facilitating comparison of the plurality of slices. ### Claim 7 (depends on 1) The method according to claim 1, further comprising generating a display image showing a minimum-intensity projection along the TI-axis to provide a global measure of the inversion effectiveness. ### Claim 8 (depends on 1) The method according to claim 1, further comprising generating a display image showing a time-to-minimum (TTM) pixel intensity facilitating a monotonic function of the pixel T1 without using nonlinear fitting. ### Claim 9 (depends on 1) The method according to claim 1, further comprising concurrently acquiring T1 map image data for a plurality of different selective inversion recovery pulses. ### Claim 10 (depends on 1) The method according to claim 1, further comprising inducing slice-dependent in-plane image shifts between the simultaneously acquired slices to improve image reconstruction. ### Claim 11 An accelerated Magnetic Resonance (MR) image system, comprising: a radio frequency (RF) signal generator configured to generate RF excitation pulses in a volume of anatomy and provide subsequent acquisition of associated RF echo data; and a magnetic field gradient generator configured to generate slice select magnetic field gradients for phase encoding and readout RF data acquisition in the volume of anatomy, the RF signal generator and the gradient generator configured; a plurality of RF coils configured to acquire a plurality of two dimensional slices of an image; and a controller configured to cause the plurality of RF coils to concurrently acquire longitudinal relaxation time (T1) image data of a plurality of different two dimensional slices within the volume of anatomy by causing the RF signal generator and the magnetic field generator to use: (i) a preparation pre-scan sequence for acquisition of image calibration data for use in separating concurrently acquired multiple slice T1 map data into separate slices; (ii) a non-selective inversion recovery pulse to invert longitudinal magnetization in the volume of anatomy; (iii) an excitation RF pulse applied to said plurality of different two dimensional slices in the volume of anatomy to rotate a portion of longitudinal magnetization in a transverse direction; and (iv) echo-planar-imaging (EPI) acquisition sampling of T1 map data of individual slices of the plurality of slices in response to the application of the excitation RF pulse. ### Claim 12 (depends on 11) The image system according to claim 11, wherein the image calibration data is acquired for each slice separately to estimate a k-space data kernel used to separate the concurrently acquired multiple slice T1 map data into the separate slices. ### Claim 13 (depends on 11) The image system according to claim 11, wherein the RF signal generator and the gradient generator acquire T1 map image data of the plurality of different two dimensional slices within said volume of anatomy during individual TI times for a plurality of successive TI times during an inversion recovery time of said volume of anatomy to provide image data representing a plurality of successive images of an individual slice during the inversion recovery time. ### Claim 14 (depends on 13) The image system according to claim 13, further comprising an image data processor configured to: (i) process data for a plurality of individual pixel locations for each of the plurality of successive images; and (ii) process individual luminance data values of an individual pixel location occurring within the plurality of successive images to provide a composite individual pixel luminance value and a composite T1 map. ### Claim 15 (depends on 11) The image system according to claim 11, further comprising an image data processor configured to fit a kernel to each slice of a pre-scan calibration dataset acquired one slice at a time and apply each kernel fit to each slice to estimate the k-space data of each individual imaging slice from collapsed slices. ### Claim 16 (depends on 11) The image system according to claim 11, wherein the RF signal generator and the gradient generator concurrently acquire T1 map image data in response to a signal indicating a start of introduction of a contrast agent into a patient vessel. ### Claim 17 (depends on 11) The image system according to claim 11, further comprising a display processor configured to generate a display image showing images representing individual slices of the plurality of slices aligned with a common timeline facilitating comparison of the plurality of slices. ### Claim 18 (depends on 11) The image system according to claim 11, wherein the RF signal generator and the gradient generator concurrently acquire T1 map image data for a plurality of different non-selective inversion recovery pulses. ### Claim 19 An article of manufacture for operating a multi-slice, multi-segment magnetic resonance (MR) imaging system, the article of manufacture comprising a non-transitory, tangible computer-readable medium holding computer-executable instructions for performing a method comprising: generating radio frequency (RF) excitation pulses in a volume of patient anatomy to provide subsequent acquisition of associated RF echo data; generating slice select magnetic field gradients for phase encoding and readout RF data acquisition in the patient anatomy; concurrently acquiring T1 map image data of a plurality of two dimensional slices of an image by an acquisition process comprising: (i) acquiring image calibration data using a pre-scan sequence; (ii) inverting a longitudinal magnetization in the volume of patient anatomy using a non-selective inversion recovery pulse; (iii) applying an excitation RF pulse to a plurality of different two dimensional slices in the volume of patient anatomy to rotate a portion of the longitudinal magnetization in a transverse direction; (iv) sampling individual slice image data of the plurality of two dimensional slices in response to applying the excitation RF pulse; and (v) separating the concurrently acquired T1 map image into separate slices. ### Claim 20 (depends on 19) The article of manufacture of claim 19, wherein acquiring the image calibration data using the pre-scan sequence further comprises acquiring each slice separately to estimate a k-space data kernel that separates the concurrently acquired T1 map image data into the separate slices.