Patents by Inventor Stephen J. Riederer

Stephen J. Riederer has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20180306884
    Abstract: Accelerated dynamic magnetic resonance imaging (“MRI”) methods in which low-rank matrix completion is implemented as a pre-processing step to fill undersampled accelerated k-space while retaining both spatial and temporal resolution are described. The undersampled k-space data are acquired using multilevel sampling, in which both uniform undersampling and non-uniform undersampling are combined to achieve high temporal resolution while retaining spatial resolution.
    Type: Application
    Filed: April 20, 2018
    Publication date: October 25, 2018
    Inventors: Joshua D. Trzasko, Eric G. Stinson, Stephen J. Riederer
  • Patent number: 9700229
    Abstract: A method of producing a series of vasculature images over an extended field of view (FOV) larger than an FOV of an MRI system includes acquiring initial time-resolved image data from the vasculature and, during the acquiring process, reconstructing, in substantially real-time, a series of three-dimensional (3D) tracking images of the initial portion of the vasculature illustrating a current position of a contrast bolus in the vasculature as the contrast bolus passes through the initial portion of the vasculature. Based on a current position of the contrast bolus, the subject is moved to a subsequent imaging station to acquire subsequent time-resolved image data and reconstruct subsequent 3D tracking images of subsequent portions of the vasculature. This process is repeated and then an image is assembled that extends over the extended FOV using the initial time-resolved image data and the subsequent time-resolved image data.
    Type: Grant
    Filed: March 30, 2012
    Date of Patent: July 11, 2017
    Assignee: MAYO FOUNDATION FOR MEDICAL EDUCATION AND RESEARCH
    Inventors: Stephen J. Riederer, Casey P. Johnson
  • Patent number: 9594143
    Abstract: A system and method for performing parallel magnetic resonance angiography includes controlling operation of a magnetic gradient system and an RF system to perform a calibration data pulse sequence to begin acquiring calibration data for use in a parallel imaging reconstruction process after receiving an indication that the subject has received a dose of a contrast agent. The acquisition of the calibration data is discontinued before the contrast agent reaches a peak concentration within a region of interest (ROI) of the subject and operation of the magnetic gradient system and RF system is controlled to perform an imaging pulse sequence in accordance with a parallel imaging acquisition to begin acquiring image data from the ROI. The image data is reconstructed into an image of the ROI using the calibration data.
    Type: Grant
    Filed: August 31, 2012
    Date of Patent: March 14, 2017
    Assignee: Mayo Foundation for Medical Education and Research
    Inventor: Stephen J. Riederer
  • Patent number: 9465091
    Abstract: A system and method are provided for producing a magnetic resonance image of a subject with a magnetic resonance imaging (MRI) system. The method includes acquiring k-space image data from a subject arranged in an MRI system by performing a pulse sequence. To perform the pulse sequence the MRI system divides k-space into a plurality of radially-extending sectors extending along a radial direction away from an origin of k-space. The plurality of radially-extending sectors include a width transverse to the radial direction that is defined by a vane angle chosen to be greater than a floating point precision of the trigonometric functions that define the radially-extending sectors. The MRI system acquires imaging data from at least the radially-extending sectors to undersample the periphery of k-space by only sampling k-space within the plurality of radial sectors and reconstructs an image of the subject using the imaging data.
    Type: Grant
    Filed: April 6, 2015
    Date of Patent: October 11, 2016
    Assignee: MAYO FOUNDATION FOR MEDICAL EDUCATION AND RESEARCH
    Inventors: Stephen J. Riederer, Norbert G. Campeau, Clifton R. Haider
  • Patent number: 9459335
    Abstract: A method for three-dimensional parallel magnetic resonance imaging (MRI) using an MRI system is provided. The method includes determining in-plane acceleration factors that optimize a selected criterion, such as an image quality criterion defined by maximal noise amplification in a reconstructed image. The estimated in-plane acceleration factors are used to establish a k-space sampling pattern, which is used to acquire k-space data. An image is reconstructed from the acquired k-space data using a parallel image reconstruction technique.
    Type: Grant
    Filed: September 13, 2013
    Date of Patent: October 4, 2016
    Assignee: Mayo Foundation For Medical Education and Reseach
    Inventors: Stephen J Riederer, Paul T Weavers
  • Publication number: 20150247910
    Abstract: A system and method are provided for producing a magnetic resonance image of a subject with a magnetic resonance imaging (MRI) system. The method includes acquiring k-space image data from a subject arranged in an MRI system by performing a pulse sequence. To perform the pulse sequence the MRI system divides k-space into a plurality of radially-extending sectors extending along a radial direction away from an origin of k-space. The plurality of radially-extending sectors include a width transverse to the radial direction that is defined by a vane angle chosen to be greater than a floating point precision of the trigonometric functions that define the radially-extending sectors. The MRI system acquires imaging data from at least the radially-extending sectors to undersample the periphery of k-space by only sampling k-space within the plurality of radial sectors and reconstructs an image of the subject using the imaging data.
    Type: Application
    Filed: April 6, 2015
    Publication date: September 3, 2015
    Inventors: Stephen J. Riederer, Norbert G. Campeau, Clifton R. Haider
  • Patent number: 9018952
    Abstract: A method for producing a time-series of images of a subject with a magnetic resonance imaging (MRI) system is provided. The MRI system is used to acquire a time-series undersampled k-space data set, in which a selected number of k-space data subsets in the time-series data set includes both image data and calibration data. Moreover, the calibration data in each of these selected number of k-space data subsets includes a portion of a desired total amount of calibration data. For example, each of these selected number of k-space data subsets include calibration data that is acquired by sampling a different partition of a calibration data sampling pattern. A time-series of images of the subject is then produced by reconstructing images of the subject from the acquired time-series of undersampled k-space data sets. These images are substantially free of undersampling artifacts.
    Type: Grant
    Filed: May 22, 2012
    Date of Patent: April 28, 2015
    Assignee: Mayo Foundation for Medical Education and Research
    Inventor: Stephen J Riederer
  • Patent number: 9002430
    Abstract: A method for performing magnetic resonance angiography and perfusion imaging using the same pulse sequence is provided. Time-resolved image data is acquired as a contrast agent passes through a subject. This image data is acquired by sampling Cartesian points in k-space that are contained within either a central region of k-space, or one of a plurality of different sets of radial sectors extending outwards from the central region. The image data is combined to form individual image frame data sets that are then reconstructed to produce a time series of image frames. From this time series, MR angiograms and perfusion maps are produced. With the added acquisition of calibration data, T1 relaxation parameters are estimated and quantitative perfusion maps produced.
    Type: Grant
    Filed: December 29, 2010
    Date of Patent: April 7, 2015
    Assignee: Mayo Foundation for Medical Education and Research
    Inventors: Stephen J Riederer, Norbert G Campeau, Clifton R Haider
  • Patent number: 8918159
    Abstract: A system and method for creating at least one angiographic image using a magnetic resonance imaging (MRI) system includes acquiring, with the MRI system and using parallel imaging techniques, a pre-contrast image data set and a post-contrast image data set of a portion of a subject having a vascular structure extending therethrough and subtracting the pre-contrast and the post-contrast image data set to generate a difference angiogram data set. The method includes reconstructing the difference angiogram data set into at least one aliased angiogram, creating a region of interest (ROI) mask from an image of the portion of the subject, and indicating a masking border surrounding the vascular structure and substantially excluding tissues surrounding the vascular structure. The method then includes de-aliasing the at least one aliased angiogram using the ROI mask to create an angiogram of the portion of the subject.
    Type: Grant
    Filed: April 18, 2012
    Date of Patent: December 23, 2014
    Assignee: Mayo Foundation for Medical Education and Research
    Inventor: Stephen J Riederer
  • Publication number: 20140077801
    Abstract: A method for three-dimensional parallel magnetic resonance imaging (MRI) using an MRI system is provided. The method includes determining in-plane acceleration factors that optimize a selected criterion, such as an image quality criterion defined by maximal noise amplification in a reconstructed image. The estimated in-plane acceleration factors are used to establish a k-space sampling pattern, which is used to acquire k-space data. An image is reconstructed from the acquired k-space data using a parallel image reconstruction technique.
    Type: Application
    Filed: September 13, 2013
    Publication date: March 20, 2014
    Inventors: Stephen J. Riederer, Paul T. Weavers
  • Publication number: 20130281831
    Abstract: A system and method for creating at least one angiographic image using a magnetic resonance imaging (MRI) system includes acquiring, with the MRI system and using parallel imaging techniques, a pre-contrast image data set and a post-contrast image data set of a portion of a subject having a vascular structure extending therethrough and subtracting the pre-contrast and the post-contrast image data set to generate a difference angiogram data set. The method includes reconstructing the difference angiogram data set into at least one aliased angiogram, creating a region of interest (ROI) mask from an image of the portion of the subject, and indicating a masking border surrounding the vascular structure and substantially excluding tissues surrounding the vascular structure. The method then includes de-aliasing the at least one aliased angiogram using the ROI mask to create an angiogram of the portion of the subject.
    Type: Application
    Filed: April 18, 2012
    Publication date: October 24, 2013
    Inventor: Stephen J. Riederer
  • Publication number: 20130123611
    Abstract: A method for performing magnetic resonance angiography and perfusion imaging using the same pulse sequence is provided. Time-resolved image data is acquired as a contrast agent passes through a subject. This image data is acquired by sampling Cartesian points in k-space that are contained within either a central region of k-space, or one of a plurality of different sets of radial sectors extending outwards from the central region. The image data is combined to form individual image frame data sets that are then reconstructed to produce a time series of image frames. From this time series, MR angiograms and perfusion maps are produced. With the added acquisition of calibration data, T1 relaxation parameters are estimated and quantitative perfusion maps produced.
    Type: Application
    Filed: December 29, 2010
    Publication date: May 16, 2013
    Inventors: Stephen J. Riederer, Norbert G. Campeau, Clifton R. Haider
  • Patent number: 8433392
    Abstract: The present invention provides an MRI system for imaging of a subject over extended field-of-view (FOV) that employs both accelerated data acquisition, which is employed while the subject is stationary, and traditional data acquisition, which is employed while the subject is moved through the MRI system. This approach provides improved spatial resolution and time efficiency compared to traditional extended FOV imaging techniques.
    Type: Grant
    Filed: September 29, 2009
    Date of Patent: April 30, 2013
    Assignee: MAYO Foundation for Medical Education and Research
    Inventor: Stephen J. Riederer
  • Publication number: 20130063146
    Abstract: A system and method for performing parallel magnetic resonance angiography includes controlling operation of a magnetic gradient system and an RF system to perform a calibration data pulse sequence to begin acquiring calibration data for use in a parallel imaging reconstruction process after receiving an indication that the subject has received a dose of a contrast agent. The acquisition of the calibration data is discontinued before the contrast agent reaches a peak concentration within a region of interest (ROI) of the subject and operation of the magnetic gradient system and RF system is controlled to perform an imaging pulse sequence in accordance with a parallel imaging acquisition to begin acquiring image data from the ROI. The image data is reconstructed into an image of the ROI using the calibration data.
    Type: Application
    Filed: August 31, 2012
    Publication date: March 14, 2013
    Applicant: Mayo Foundation for Medical Education and Research
    Inventor: Stephen J. Riederer
  • Patent number: 8334694
    Abstract: An improved self-calibration method for accelerated magnetic resonance imaging (MRI) using inversion recovery pulse sequences allows calibration data for determining coil sensitivity profiles to be acquired by employing a calibration pulse sequence within the delay time of an inversion recovery pulse sequence. The calibration pulse sequence includes a constrained number of calibration pulses having small flip angles so that acceptable longitudinal magnetization recovery is provided.
    Type: Grant
    Filed: January 20, 2010
    Date of Patent: December 18, 2012
    Assignee: MAYO Foundation for Medical Education and Research
    Inventors: Ek Tsoon Tan, Stephen J Riederer
  • Publication number: 20120299590
    Abstract: A method for producing a time-series of images of a subject with a magnetic resonance imaging (MRI) system is provided. The MRI system is used to acquire a time-series undersampled k-space data set, in which a selected number of k-space data subsets in the time-series data set includes both image data and calibration data. Moreover, the calibration data in each of these selected number of k-space data subsets includes a portion of a desired total amount of calibration data. For example, each of these selected number of k-space data subsets include calibration data that is acquired by sampling a different partition of a calibration data sampling pattern. A time-series of images of the subject is then produced by reconstructing images of the subject from the acquired time-series of undersampled k-space data sets. These images are substantially free of undersampling artifacts.
    Type: Application
    Filed: May 22, 2012
    Publication date: November 29, 2012
    Inventor: Stephen J. Riederer
  • Patent number: 8320646
    Abstract: An MRI system produces a three-dimensional image by acquiring NMR signals that fully sample a central region of k-space and partially sample peripheral k-space as a set of asymmetric radial sectors. The NMR signals are acquired with a plurality of receive channels and coils. An image is reconstructed using a homodyne reconstruction combined with SENSE processing.
    Type: Grant
    Filed: May 2, 2006
    Date of Patent: November 27, 2012
    Assignee: MAYO Foundation for Medical Education and Research
    Inventors: Houchun H. Hu, Ananth J. Madhuranthakam, Stephen J. Riederer
  • Patent number: 8299793
    Abstract: The present invention is a coil array for an MRI system that is designed to improve 2D accelerated imaging of an object having significantly different fields of view in two phase-encoding directions. This is achieved by having a first set of coil elements whose sizes are tuned to optimize acceleration along a first phase-encoding direction and a second set of coil elements whose sizes are tuned to optimize acceleration along a second-phase encoding direction. Images acquired in accordance with the present invention exhibit improved signal to noise ratio at a given acceleration factor when compared to images acquired using a traditional MR coil array.
    Type: Grant
    Filed: January 11, 2010
    Date of Patent: October 30, 2012
    Assignee: MAYO Foundation for Medical Education and Research
    Inventors: Stephen J. Riederer, Clifton R. Haider, Phillip J. Rossman
  • Publication number: 20120253175
    Abstract: A method of producing a series of vasculature images over an extended field of view (FOV) larger than an FOV of an MRI system includes acquiring initial time-resolved image data from the vasculature and, during the acquiring process, reconstructing, in substantially real-time, a series of three-dimensional (3D) tracking images of the initial portion of the vasculature illustrating a current position of a contrast bolus in the vasculature as the contrast bolus passes through the initial portion of the vasculature. Based on a current position of the contrast bolus, the subject is moved to a subsequent imaging station to acquire subsequent time-resolved image data and reconstruct subsequent 3D tracking images of subsequent portions of the vasculature. This process is repeated and then an image is assembled that extends over the extended FOV using the initial time-resolved image data and the subsequent time-resolved image data.
    Type: Application
    Filed: March 30, 2012
    Publication date: October 4, 2012
    Inventors: Stephen J. Riederer, Casey P. Johnson
  • Patent number: 8155419
    Abstract: An MRI system produces a three-dimensional image by acquiring NMR signals that fully sample a central region of k-space and partially sample peripheral region of k-space. Specifically, k-space is arranged as a three-dimensional (3D) Cartesian grid of points that is divided into a central region of k-space and a peripheral region of k-space. Points are selected in k-space within a plurality of radial vanes that extend radially outward from the central region of k-space through the peripheral region of k-space as viewed in a plane sampled by two phase encoding gradients to create a plurality of gaps between the radial vanes that is substantially a factor of N times greater in area than the radial vanes. Using an MRI system having arrays of RF receiver coils, NMR signals are acquired from a subject to fully sample the central region of the 3D k-space and undersample the peripheral region of k-space by only sampling k-space within the plurality of radial vanes.
    Type: Grant
    Filed: May 4, 2009
    Date of Patent: April 10, 2012
    Assignee: Mayo Foundation for Medical Education and Research
    Inventors: Clifton R. Haider, Stephen J. Riederer