Patents by Inventor Douglas A. Ortendahl

Douglas A. Ortendahl 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: 5085219
    Abstract: An adjustable holder for a magnetic resonance imaging RF surface coil for imaging a part of the body such as the temporomandibular joint. Elements are provided for positioning and securing the RF surface coil at a first predetermined point along a longitudinal axis of the holder and for positioning and securing the RF surface coil at a second predetermined point transverse to the longitudinal axis and at a radial distance R from the longitudinal axis. The preferred embodiment provides orbital movement of the surface coil about the longitudinal axis using a pair of U-shaped runner guides disposed substantially transverse to the longitudinal axis and adjustable clamps in cooperative engagement with the runner guides. The surface coil may be adjusted along a path transverse to the longitudinal axis by way of an adjustable shaft or arm which can be moved inwardly and outwardly, and the surface coil can be pivoted in a step-wise manner using a pivot head having a plurality of equally spaced detents.
    Type: Grant
    Filed: October 30, 1987
    Date of Patent: February 4, 1992
    Assignee: The Regents of the University of California
    Inventors: Douglas A. Ortendahl, Brenda G. Nichols, Ernesto Zepeda, Matthias Gyori, Louis T. Kircos
  • Patent number: 4721912
    Abstract: NMR imaging apparatus and method is arranged so as elicit NMR image response data in a predetermined order which provides the more significant lower spatial frequency image data during an initial portion of a relatively long complete image data acquisition cycle. The remaining higher spatial frequency image data is captured during subsequent portions of the overall image data acquisition cycle. In this manner, apparent motion artifact in the resulting image is reduced. Furthermore, such a special data acquisition sequence permits image reconstruction processes to produce a recognizable image at an earlier time in the complete data gathering cycle thus permitting a more timely image display for the apparatus operator to use in monitoring and/or controlling the NMR imaging procedure.
    Type: Grant
    Filed: September 30, 1985
    Date of Patent: January 26, 1988
    Assignee: The Reagents of the University of California
    Inventors: Leon Kaufman, Lawrence E. Crooks, Douglas A. Ortendahl
  • Patent number: 4604579
    Abstract: An analytic closed solution for the spin-lattice relaxation time T1 is provided in terms of the repetition interval time TR and the differing NMR signal response intensities I.sub.1 and I.sub.2 obtained when using different repetition intervals TR.sub.1 and TR.sub.2 which are related to one another by integer multipliers. The result is a method and apparatus which directly and non-iteratively generate a spin-lattice relaxation time signal value T1 for each voxel within a selected region of an object under test so as to quickly, economically and accurately produce a T1 image of nutated nuclei within the region.
    Type: Grant
    Filed: July 21, 1983
    Date of Patent: August 5, 1986
    Assignee: The Regents of the University of California
    Inventors: Clifford R. Cannon, Douglas A. Ortendahl