Patents by Inventor Ralph E. Hurd

Ralph E. Hurd 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).

  • Patent number: 9116218
    Abstract: A system for magnetic resonance (MR) spectroscopy includes a plurality of gradient coils positioned about a bore of a magnet and an RF coil assembly coupled to a pulse generator to emit RF pulse sequences and arranged to receive resulting MR signals from a subject of interest. A system control is also included in the MR spectroscopy system and is coupled to the plurality of gradient coils and the RF coil assembly. The system control is programmed to cause the RF coil assembly to emit a first RF pulse and a second RF pulse, wherein at least one of the first and second RF pulses is spectrally selective and at least one of the first and second RF pulses is spatially selective. The system control is also programmed to cause the RF coil assembly to emit a third RF pulse after a pre-defined time delay to generate a stimulated echo and detect MR signals resulting from the stimulated echo.
    Type: Grant
    Filed: July 28, 2010
    Date of Patent: August 25, 2015
    Assignee: General Electric Company
    Inventor: Ralph E. Hurd
  • Publication number: 20140330110
    Abstract: A system and method for improving available signal-to-noise ratio (SNR) and speed of MR imaging of hyperpolarized substances is disclosed. The system and method include decoupling spin effects of hydrogen nuclei from non-hydrogen nuclei of interest during sampling of MR signals therefrom. Though the hydrogen nuclei of the hyperpolarized substance may not be directly bonded to the non-hydrogen nuclei of interest, resonance splitting may still impact SNR. Long range decoupling improves T2* time, and thus preserves signal strength and available SNR.
    Type: Application
    Filed: July 23, 2014
    Publication date: November 6, 2014
    Inventor: Ralph E. Hurd
  • Patent number: 8812076
    Abstract: A system and method for improving available signal-to-noise ratio (SNR) and speed of MR imaging of hyperpolarized substances is disclosed. The system and method include decoupling spin effects of hydrogen nuclei from non-hydrogen nuclei of interest during sampling of MR signals therefrom. Though the hydrogen nuclei of the hyperpolarized substance may not be directly bonded to the non-hydrogen nuclei of interest, resonance splitting may still impact SNR. Long range decoupling improves T2* time, and thus preserves signal strength and available SNR.
    Type: Grant
    Filed: November 21, 2006
    Date of Patent: August 19, 2014
    Assignee: General Electric Company
    Inventor: Ralph E. Hurd
  • Publication number: 20100283465
    Abstract: A system for magnetic resonance (MR) spectroscopy includes a plurality of gradient coils positioned about a bore of a magnet and an RF coil assembly coupled to a pulse generator to emit RF pulse sequences and arranged to receive resulting MR signals from a subject of interest. A system control is also included in the MR spectroscopy system and is coupled to the plurality of gradient coils and the RF coil assembly. The system control is programmed to cause the RF coil assembly to emit a first RF pulse and a second RF pulse, wherein at least one of the first and second RF pulses is spectrally selective and at least one of the first and second RF pulses is spatially selective. The system control is also programmed to cause the RF coil assembly to emit a third RF pulse after a pre-defined time delay to generate a stimulated echo and detect MR signals resulting from the stimulated echo.
    Type: Application
    Filed: July 28, 2010
    Publication date: November 11, 2010
    Inventor: Ralph E. Hurd
  • Patent number: 7772844
    Abstract: A system for magnetic resonance (MR) spectroscopy includes a plurality of gradient coils positioned about a bore of a magnet and an RF coil assembly coupled to a pulse generator to emit RF pulse sequences and arranged to receive resulting MR signals from a subject of interest. A system control is also included in the MR spectroscopy system and is coupled to the plurality of gradient coils and the RF coil assembly. The system control is programmed to cause the RF coil assembly to emit a first RF pulse and a second RF pulse, wherein at least one of the first and second RF pulses is spectrally selective and at least one of the first and second RF pulses is spatially selective. The system control is also programmed to cause the RF coil assembly to emit a third RF pulse after a pre-defined time delay to generate a stimulated echo and detect MR signals resulting from the stimulated echo.
    Type: Grant
    Filed: January 30, 2008
    Date of Patent: August 10, 2010
    Assignee: General Electric Company
    Inventor: Ralph E. Hurd
  • Publication number: 20090189605
    Abstract: A system for magnetic resonance (MR) spectroscopy includes a plurality of gradient coils positioned about a bore of a magnet and an RF coil assembly coupled to a pulse generator to emit RF pulse sequences and arranged to receive resulting MR signals from a subject of interest. A system control is also included in the MR spectroscopy system and is coupled to the plurality of gradient coils and the RF coil assembly. The system control is programmed to cause the RF coil assembly to emit a first RF pulse and a second RF pulse, wherein at least one of the first and second RF pulses is spectrally selective and at least one of the first and second RF pulses is spatially selective. The system control is also programmed to cause the RF coil assembly to emit a third RF pulse after a pre-defined time delay to generate a stimulated echo and detect MR signals resulting from the stimulated echo.
    Type: Application
    Filed: January 30, 2008
    Publication date: July 30, 2009
    Inventor: Ralph E. Hurd
  • Publication number: 20090060841
    Abstract: A system and method for MR imaging includes a magnetic resonance imaging (MRI) system having a plurality of gradient coils positioned about a bore of a magnet, and an RF transceiver system and an RF switch controlled by a pulse module to transmit RF signals to an RF coil assembly to acquire MR images. The apparatus further includes a controller programmed to determine a variable flip angle (VFA) sequence to excite a hyperpolarized material in a subject and to determine a delay period during which application of the VFA sequence is delayed after injection of a hyperpolarized contrast agent. The delay period is based on dynamic data of the hyperpolarized material acquired from the subject. The controller is also programmed to cause application of the VFA sequence to excite the hyperpolarized material in the subject and to acquire MR data from the hyperpolarized material using an isotropic centric phase encoding (iCPE) technique.
    Type: Application
    Filed: March 10, 2008
    Publication date: March 5, 2009
    Inventors: Yi-Fen Yen, Ralph E. Hurd, Susan J. Kohler
  • Publication number: 20080116890
    Abstract: A system and method for improving available signal-to-noise ratio (SNR) and speed of MR imaging of hyperpolarized substances is disclosed. The system and method include decoupling spin effects of hydrogen nuclei from non-hydrogen nuclei of interest during sampling of MR signals therefrom. Though the hydrogen nuclei of the hyperpolarized substance may not be directly bonded to the non-hydrogen nuclei of interest, resonance splitting may still impact SNR. Long range decoupling improves T2* time, and thus preserves signal strength and available SNR.
    Type: Application
    Filed: November 21, 2006
    Publication date: May 22, 2008
    Inventor: Ralph E. Hurd
  • Patent number: 7184813
    Abstract: A technique is set forth for MR spectroscopy that is capable of reducing signal overlap between metabolite signals for improved clinical analysis of metabolite content. The technique includes varying an echo time across a scanning dimension. Once a span of echo time for an acquisition dimension is determined, and the number of acquisition data points is known, a variance between echo times can be determined. A pulse sequence with differing echo times is then applied for each frame, and after data is acquired, an image is reconstructed that significantly improves metabolite signal separation.
    Type: Grant
    Filed: April 19, 2005
    Date of Patent: February 27, 2007
    Assignee: General Electric Company
    Inventors: Ralph E. Hurd, Napapon Sailasuta
  • Patent number: 6987997
    Abstract: A technique is set forth for MR spectroscopy that is capable of reducing signal overlap between metabolite signals for improved clinical analysis of metabolite content. The technique includes varying an echo time across a scanning dimension. Once a span of echo time for an acquisition dimension is determined, and the number of acquisition data points is known, a variance between echo times can be determined. A pulse sequence with differing echo times is then applied for each frame, and after data is acquired, an image is reconstructed that significantly improves metabolite signal separation.
    Type: Grant
    Filed: June 18, 2003
    Date of Patent: January 17, 2006
    Assignee: General Electric Company
    Inventors: Ralph E. Hurd, Napapon Sailasuta
  • Patent number: 6979999
    Abstract: A system and method for imaging is presented that includes exciting water-exchangeable spins in oxygen-bearable molecules in a ROI having a change in oxygen status. A proton transfer within the ROI from exchangeable protons within water is detected such that changes in oxygen levels across the ROI are distinguishable.
    Type: Grant
    Filed: February 26, 2004
    Date of Patent: December 27, 2005
    Assignee: General Electric Company
    Inventor: Ralph E. Hurd
  • Patent number: 6242915
    Abstract: A field-frequency lock system for an MRI system includes a microcoil and resonant sample located to sense changes in the polarizing magnetic field. Changes are detected as a shift in frequency of the NMR signal produced by the resonant sample, and the frequency shift is used to compensate the MRI system. Compensation is achieved by adjusting the RF reference signal employed in the MRI system transceiver.
    Type: Grant
    Filed: August 27, 1999
    Date of Patent: June 5, 2001
    Assignee: General Electric Company
    Inventor: Ralph E. Hurd
  • Patent number: 6137290
    Abstract: Chemical shift error in proton magnetic resonance spectroscopy is reduced by applying a volume excitation pulse sequence such as PRESS and very selective out-of-volume saturation pulses to limit that volume to a volume-of-interest free of the misregistration errors associated with the excitation sequence. The resulting volume is then only limited by the very small chemical shift misregistration of the very selective saturation pulses.
    Type: Grant
    Filed: February 19, 1998
    Date of Patent: October 24, 2000
    Assignee: General Electric Company
    Inventors: Ralph E. Hurd, Napapon Sailasuta, James Tropp, Patrick L. Le Roux
  • Patent number: 6104191
    Abstract: Disclosed is improved quantitative in vivo spectroscopy by means of F1-oversampled J-Resolved 2D spectroscopy. Reconstruction makes full use of internal signals for 2D water lineshape, T.sub.2 and partial volume correction, and analysis uses 2D complex model spectra fitting. The preferred embodiment of the new method integrates these features into PRESS localized brain spectroscopy and is carried out without the need for water suppression.
    Type: Grant
    Filed: March 17, 1998
    Date of Patent: August 15, 2000
    Assignee: General Electric Company
    Inventor: Ralph E. Hurd
  • Patent number: 6069478
    Abstract: A pure water subtraction method for eliminating interfering sidebands of residual water including spurious signals from extraneous sources such as eddy current effects, Bo magnetic field drift, patient motion and the like. Unsuppressed and partially water suppressed magnetic signal data are obtained, and a low frequency water-phase-correction is applied thereto. The water phase corrected partially suppressed data is subtracted from the water phase corrected unsuppressed data to get a pure water reference (i.e. metabolite signals cancel). A scaled version of the pure water reference is subtracted from the partially suppressed data to eliminate spurious water signals.
    Type: Grant
    Filed: November 24, 1997
    Date of Patent: May 30, 2000
    Assignee: General Electric Corporation
    Inventor: Ralph E. Hurd
  • Patent number: 5804966
    Abstract: Susceptibility artifacts in slice selective volume magnetic resonance spectroscopy are reduced by applying phase encoding at a nominal resolution equal to or larger than the slice selection dimensions. In a preferred embodiment of the method, phase encoding is applied along the axes of the first and last RF slice selections. The volume of interest is contained completely within a single pixel defined by the 2D phase encoding. Unsuppressed water reference signal from the volume of interest is relatively unaffected by these artifacts and is collected without phase encoding.
    Type: Grant
    Filed: September 10, 1996
    Date of Patent: September 8, 1998
    Assignee: General Electric Company
    Inventor: Ralph E. Hurd
  • Patent number: 5262723
    Abstract: A signal function S(t.sub.1, t.sub.2) is obtained from a plurality of coherence transfer pathways in a single acquisition by preparing a molecular system in a coherent non-equilibrium state, and alternately and sequentially detecting signals at individual sampling points, in t.sub.2, from the plurality of coherence transfer pathways by using gradient refocusing of a new pathway after signal detection at a sampling point in another pathway. A frequency domain spectrum S(.omega..sub.1,.omega..sub.2) is constructed by first Fourier transforming the time domain signals S(t.sub.1, t.sub.2) in the t.sub.2 dimension and producing real and imaginary components which modulate as sine and cosine signals in t.sub.1. The real (.omega..sub.2) cosine (t.sub.1) components are combined with the imaginary (.omega..sub.2) sine (t.sub.1) components to form a complex data set S(t.sub.1, .omega..sub.2) that is amplitude modulated in t.sub.1. The complex data set is then Fourier transformed in the t.sub.
    Type: Grant
    Filed: July 9, 1991
    Date of Patent: November 16, 1993
    Assignee: General Electric Company
    Inventors: Ralph E. Hurd, Boban K. John, Harris D. Plant
  • Patent number: 5168229
    Abstract: A signal function S(t.sub.1, t.sub.2) is obtained from a plurality of coherence transfer pathways in a single acquisition by preparing a molecular system in a coherent non-equilibrium state, and alternately and sequentially detecting signals at individual sampling points, in t.sub.2, from the plurality of coherence transfer pathways by using gradient refocusing of a new pathway after siganl detection at a sampling point in another pathway. The gradient encoding and refocusing of coherence pathways can use inhomogeneous rf-pulses (B.sub.1 gradients) or B.sub.0 field gradients. The coherence transfer pathways can be sequentially selected in an arbitrary order.
    Type: Grant
    Filed: April 2, 1991
    Date of Patent: December 1, 1992
    Assignee: General Electric Company
    Inventors: Ralph E. Hurd, Boban K. John, Harris D. Plant
  • Patent number: 5111819
    Abstract: A multiple quantum excitation pulse sequence for producing NMR signals is optimized for reconstructing images of the distribution and levels of metabolites in vivo using magnetic field gradients. Unwanted signals from water are reduced by application of composite magnetic field gradients, unwanted signals from lipids are reduced by use of a frequency selective pulse optimized to null the lipid signals, and the signal-to-noise ratio of the signals produced by lactate are enhanced by the addition of two 180.degree. excitation pulses to the sequence.
    Type: Grant
    Filed: November 25, 1988
    Date of Patent: May 12, 1992
    Assignee: General Electric
    Inventor: Ralph E. Hurd
  • Patent number: 5077524
    Abstract: A method for obtaining high resolution NMR spectra without the need for phase cycling includes the application of magnetic field gradient pulses to select specific coherences. By using actively shielded gradients, a gradient pulse is applied during the evolution period of the selected coherence to dephase the transverse magnetization and another gradient pulse refocuses the desired coherences remaining during the acquisition period.
    Type: Grant
    Filed: June 7, 1990
    Date of Patent: December 31, 1991
    Assignee: General Elecric
    Inventors: Ralph E. Hurd, Michael G. Boucher