Patents Assigned to CR DEVELOPMENT AB
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Publication number: 20220221542Abstract: According to a first aspect of the present inventive concept, there is provided a method for performing a diffusion weighted magnetic resonance measurement on a sample, the method comprising: operating a magnetic resonance scanner to apply a diffusion encoding sequence to the sample; and operating the magnetic resonance scanner to acquire from the sample one or more echo signals; wherein the diffusion encoding sequence comprises a diffusion encoding time-dependent magnetic field gradient g(t) with non-zero components gl(t) along at least two orthogonal directions y and z, and a b-tensor having at least two non-zero eigenvalues, the magnetic field gradient comprising a first and subsequent second encoding block, wherein an n-th order gradient moment magnitude along direction l ? (y, z) is given by Mnl(t)|=|?0tgl(t?)t?n dt?| and the first encoding block is adapted to yield, at an end of the first encoding block: along said direction y, |Mny(t)|?Tn for each 0?n?m, where Tn is a predetermined n-th order thresholdType: ApplicationFiled: April 24, 2020Publication date: July 14, 2022Applicant: CR Development ABInventors: Irvin Teh, Samo Lasic, Markus Nilsson, Filip Szczepankiewicz
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Patent number: 11061096Abstract: According to an aspect of the present inventive concept there is provided a method of performing diffusion weighted magnetic resonance measurements on a sample, the method comprising: performing a plurality of diffusion weighted magnetic resonance measurements on the sample, wherein said plurality of measurements includes: a first measurement with a first diffusion encoding sequence having a tensor representation with three non-zero eigenvalues, a second measurement with a second diffusion encoding sequence, and a third measurement with a third diffusion encoding sequence, wherein the second and the third diffusion encoding sequence have different spectral content.Type: GrantFiled: November 9, 2017Date of Patent: July 13, 2021Assignee: CR Development ABInventors: Samo Lasic, Daniel Topgaard, Markus Nilsson, Hans Magnus Henrik Lundell
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Patent number: 10948560Abstract: According to an aspect of the present inventive concept there is provided a method of performing diffusion weighted magnetic resonance measurements on a sample, the method includes performing diffusion weighted magnetic resonance measurements on the sample, where the measurements include a first measurement with a first diffusion encoding sequence having a first diffusion weighting tensor representation B1 with at least two non-zero eigenvalues and a second measurement with a second diffusion encoding sequence having a second diffusion weighting tensor representation B2 with at least two non-zero eigenvalues.Type: GrantFiled: November 9, 2017Date of Patent: March 16, 2021Assignee: CR Development ABInventors: Samo Lasic, Daniel Topgaard, Markus Nilsson, Hans Magnus Henrik Lundell
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Patent number: 10788558Abstract: The present invention discloses a method for magnetic resonance (MR) imaging comprising acquiring at least two MR images with different motion-weighting originating from a RF and gradient pulse sequence causing signal attenuation from diffusion but not flow (flow-compensated data); acquiring at least two MR images with different motion-weighting originating from a RF and gradient pulse sequence causing signal attenuation from diffusion and flow (non-compensated data); performing a model fit to the flow-compensated and non-compensated data in which at least one of the adjustable parameters are constrained to be the same for both sets of data; and obtaining quantitative information on microscopic flow by extracting at least one parameter of the intravoxel incoherent motion (IVIM) effect from the model fit, said method being directed to diffusion-perfusion.Type: GrantFiled: March 29, 2018Date of Patent: September 29, 2020Assignee: CR Development ABInventors: Daniel Topgaard, Samo Lasic
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Patent number: 10649057Abstract: A method for MRI includes performing an MRI experiment on a material to acquire an echo attenuation data set using a gradient modulation scheme comprising 1D diffusion encoding and to acquire an echo attenuation data set using a gradient modulation scheme comprising 2D diffusion encoding, determining respective first-order deviations ?2 from mono-exponential decay in said echo attenuation data sets, and generating MRI parameter maps or MR image contrast based on said first-order deviations ?2.Type: GrantFiled: February 12, 2019Date of Patent: May 12, 2020Assignee: CR Development ABInventors: Daniel Topgaard, Samo Lasic, Markus Nilsson
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Publication number: 20190187233Abstract: The present invention describes a method for quantifying microscopic diffusion anisotropy and/or mean diffusivity in a material by analysis of echo attenuation curves acquired with two different gradient modulations schemes, wherein one gradient modulation scheme is based on isotropic diffusion weighting and the other gradient modulation scheme is based on non-isotropic diffusion weighting, and wherein the method comprises analyzing by comparing the signal decays of the two acquired echo attenuation curves.Type: ApplicationFiled: February 12, 2019Publication date: June 20, 2019Applicant: CR Development ABInventors: Daniel TOPGAARD, Samo Lasic, Markus Nilsson
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Patent number: 10295639Abstract: The present invention describes a method for magnetic resonance (MR) and/or MR imaging, comprising acquisition of signals and MR images originating from a RE and gradient sequence causing isotropic diffusion weighting of signal attenuation, wherein the isotropic diffusion weighting is achieved by one time-dependent dephasing vector q(t) having an orientation, wherein the isotropic diffusion weighting is proportional to the trace of a diffusion tensor D, and wherein the orientation of the time-dependent dephasing vector q(t) is either varied discretely in more than three directions in total, or changed continuously, or changed in a combination of discretely and continuously during the gradient pulse sequence, 0?t?echo time, where t represents the time. The method may be performed during a single shot (single MR excitation).Type: GrantFiled: September 28, 2017Date of Patent: May 21, 2019Assignee: CR Development ABInventors: Daniel Topgaard, Samo Lasic, Markus Nilsson
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Publication number: 20190011519Abstract: According to an aspect of the present inventive concept, there is provided a method of extracting information about a sample, the method comprising: performing a plurality of magnetic resonance measurements on the sample, each measurement including subjecting the sample to an encoding sequence, at least a part of the sequence being adapted to encode a magnetic resonance signal attenuation due to nuclear relaxation and diffusion, wherein at least one parameter of a gradient pulse sequence is varied between at least a subset of said plurality of measurements, and at least one measurement of said subset includes a gradient pulse sequence having a diffusion-encoding tensor representation with more than one non-zero eigenvalue, and wherein at least a subset of said plurality of measurements include encoding for different levels of magnetic resonance signal attenuation due to nuclear relaxation; and extracting information about the sample from signals resulting from said plurality of magnetic resonance measurementsType: ApplicationFiled: December 22, 2016Publication date: January 10, 2019Applicant: CR Development ABInventors: Daniel Topgaard, Samo Lasic
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Publication number: 20180224514Abstract: The present invention discloses a method for magnetic resonance (MR) imaging comprising acquiring at least two MR images with different motion-weighting originating from a RF and gradient pulse sequence causing signal attenuation from diffusion but not flow (flow-compensated data); acquiring at least two MR images with different motion-weighting originating from a RF and gradient pulse sequence causing signal attenuation from diffusion and flow (non-compensated data); performing a model fit to the flow-compensated and non-compensated data in which at least one of the adjustable parameters are constrained to be the same for both sets of data; and obtaining quantitative information on microscopic flow by extracting at least one parameter of the intravoxel incoherent motion (IVIM) effect from the model fit, said method being directed to diffusion-perfusion.Type: ApplicationFiled: March 29, 2018Publication date: August 9, 2018Applicant: CR Development ABInventors: Daniel TOPGAARD, Samo Lasic
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Patent number: 10031204Abstract: The present invention discloses a method for magnetic resonance (MR) imaging comprising: acquiring at least two MR images with different motion-weighting originating from a RF and gradient pulse sequence causing signal attenuation from diffusion but not flow (flow-compensated data); acquiring at least two MR images with different motion-weighting originating from a RF and gradient pulse sequence causing signal attenuation from diffusion and flow (non-compensated data); performing a model fit to the flow-compensated and non-compensated data in which at least one of the adjustable parameters are constrained to be the same for both sets of data; and obtaining quantitative information on microscopic flow by extracting at least one parameter of the intravoxel incoherent motion (IVIM) effect from the model fit, said method being directed to diffusion-perfusion.Type: GrantFiled: June 24, 2013Date of Patent: July 24, 2018Assignee: CR Development ABInventors: Daniel Topgaard, Samo Lasic
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Patent number: 9995812Abstract: The present invention describes a method for quantifying microscopic diffusion anisotropy and/or mean diffusivity in a material by analysis of echo attenuation curves acquired with two different gradient modulations schemes, wherein one gradient modulation scheme is based on isotropic diffusion weighting and the other gradient modulation scheme is based on non-isotropic diffusion weighting, and wherein the method comprises analyzing by comparing the signal decays of the two acquired echo attenuation curves.Type: GrantFiled: May 3, 2013Date of Patent: June 12, 2018Assignee: CR Development ABInventors: Daniel Topgaard, Samo Lasic, Markus Nilsson
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Patent number: 9891302Abstract: According to an aspect of the present inventive concept there is provided a method for quantifying isotropic diffusion and/or anisotropic diffusion in a sample, the method comprising: performing diffusion weighted magnetic resonance measurements on the sample using diffusion encoding magnetic gradient pulse sequences Gi=1. . . m, wherein each magnetic gradient pulse sequence Gi is generated such that a diffusion encoding tensor bi for the magnetic gradient pulse sequence Gi has one to three non-zero eigenvalues, where bi=Formula (I), qi(t) is proportional to Formula (II) and t is an echo time.Type: GrantFiled: February 10, 2015Date of Patent: February 13, 2018Assignee: CR DEVELOPMENT ABInventors: Daniel Topgaard, Samo Lasic, Markus Nilsson
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Publication number: 20180017648Abstract: The present invention describes a method for magnetic resonance (MR) and/or MR imaging, comprising acquisition of signals and MR images originating from a RE and gradient sequence causing isotropic diffusion weighting of signal attenuation, wherein the isotropic diffusion weighting is achieved by one time-dependent dephasing vector q(t) having an orientation, wherein the isotropic diffusion weighting is proportional to the trace of a diffusion tensor D, and wherein the orientation of the time-dependent dephasing vector q(t) is either varied discretely in more than three directions in total, or changed continuously, or changed in a combination of discretely and continuously during the gradient pulse sequence, 0?t?echo time, where t represents the time. The method may be performed during a single shot (single MR excitation).Type: ApplicationFiled: September 28, 2017Publication date: January 18, 2018Applicant: CR Development ABInventors: Daniel TOPGAARD, Samo LASIC, Markus NILSSON
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Patent number: 9791534Abstract: The present invention describes a method for magnetic resonance (MR) and/or MR imaging, comprising acquisition of signals and MR images originating from a RF and gradient sequence causing isotropic diffusion weighting of signal attenuation, wherein the isotropic diffusion weighting is achieved by one time-dependent dephasing vector q(t) having an orientation, wherein the isotropic diffusion weighting is proportional to the trace of a diffusion tensor D, and wherein the orientation of the time-dependent dephasing vector q(t) is either varied discretely in more than three directions in total, or changed continuously, or changed in a combination of discretely and continuously during the gradient pulse sequence, 0?t?echo time, where t represents the time. The method may be performed during a single shot (single MR excitation).Type: GrantFiled: May 3, 2013Date of Patent: October 17, 2017Assignee: CR DEVELOPMENT ABInventors: Daniel Topgaard, Samo Lasic, Markus Nilsson
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Publication number: 20160356873Abstract: According to an aspect of the present inventive concept there is provided a method for quantifying isotropic diffusion and/or anisotropic diffusion in a sample, the method comprising: performing diffusion weighted magnetic resonance measurements on the sample using diffusion encoding magnetic gradient pulse sequences Gi=1 . . . m, wherein each magnetic gradient pulse sequence Gi is generated such that a diffusion encoding tensor bi for the magnetic gradient pulse sequence Gi has one to three non-zero eigenvalues, where bi=Formula (I), qi(t) is proportional to Formula (II) and t is an echo time.Type: ApplicationFiled: February 10, 2015Publication date: December 8, 2016Applicant: CR Development ABInventors: Daniel Topgaard, Samo Lasic, Markus Nilsson
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Publication number: 20150168527Abstract: The present invention discloses a method for magnetic resonance (MR) imaging comprising: acquiring at least two MR images with different motion-weighting originating from a RF and gradient pulse sequence causing signal attenuation from diffusion but not flow (flow-compensated data); acquiring at least two MR images with different motion-weighting originating from a RF and gradient pulse sequence causing signal attenuation from diffusion and flow (non-compensated data); performing a model fit to the flow-compensated and non-compensated data in which at least one of the adjustable parameters are constrained to be the same for both sets of data; and obtaining quantitative information on microscopic flow by extracting at least one parameter of the intravoxel incoherent motion (IVIM) effect from the model fit, said method being directed to diffusion-perfusion.Type: ApplicationFiled: June 24, 2013Publication date: June 18, 2015Applicant: CR DEVELOPMENT ABInventors: Daniel Topgaard, Samo Lasic
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Patent number: 8810244Abstract: The present invention refers to a method for magnetic resonance imaging or nuclear magnetic resonance spectroscopy comprising emitting a radio frequency and gradient pulse sequence towards an object being subjected to a magnetic field, wherein said object comprises a molecule having an atom with a nuclear spin differing from 0, encoding, detecting and acquiring a magnetic resonance signal from said object corresponding to said emitted radio frequency and gradient pulse sequence, wherein the radio frequency and gradient pulse sequence comprises a first weighting block, a mixing block with duration tm and a second weighting block, and wherein encoding, detecting and acquiring the magnetic resonance signal from said object is limited to initial decay of the signal intensity I with increasing strength of at least one of the first weighting block and the second weighting block, wherein the variation of the initial signal decay rate with tm is analysed to obtain the apparent exchange rate AXR.Type: GrantFiled: April 22, 2010Date of Patent: August 19, 2014Assignee: CR Development ABInventor: Daniel Topgaard
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Patent number: 8565854Abstract: A method, system, computer-readable medium, use, and pulse sequence for magnetic resonance imaging or nuclear magnetic resonance is provided for determining the rate of molecular exchange between components with different diffusion characteristics. The present invention encodes the magnetic resonance signal for exchange utilizing judiciously designed protocols for varying the parameters of a pulse sequence comprising a pair of diffusion weighting blocks separated by a mixing time.Type: GrantFiled: May 30, 2008Date of Patent: October 22, 2013Assignee: CR Development ABInventors: Karin Bryskhe, Daniel Topgaard, Anna Stenstam
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Publication number: 20120062229Abstract: The present invention refers to a method for magnetic resonance imaging or nuclear magnetic resonance spectroscopy comprising emitting a radio frequency and gradient pulse sequence towards an object being subjected to a magnetic field, wherein said object comprises a molecule having an atom with a nuclear spin differing from 0, encoding, detecting and acquiring a magnetic resonance signal from said object corresponding to said emitted radio frequency and gradient pulse sequence, wherein the radio frequency and gradient pulse sequence comprises a first weighting block, a mixing block with duration tm and a second weighting block, and wherein encoding, detecting and acquiring the magnetic resonance signal from said object is limited to initial decay of the signal intensity I with increasing strength of at least one of the first weighting block and the second weighting block, wherein the variation of the initial signal decay rate with tm is analysed to obtain the apparent exchange rate AXR.Type: ApplicationFiled: April 22, 2010Publication date: March 15, 2012Applicant: CR DEVELOPMENT ABInventor: Daniel Topgaard