Patents by Inventor Donald J. Lyman

Donald J. Lyman 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: 4334327
    Abstract: A ureter prosthesis fabricated from copolyurethane materials which are non-reactive in the urinary environment and adapted for fixation within a patient to avoid adverse migration. This ureter prosthesis can be adapted for intermediate location along a ureter or can be constructed with one-way valve means appropriate for implantation into the bladder lumen without a resulting vesico-ureteral reflux. The ureter prosthesis includes an elongate duct having a lumen whose interior surface is ultrasmooth based on microscopic inspection. An exterior cuff with terminal and intermediate sewing projections is formed around a portion of the elongate duct to enable its fixation by suturing to appropriate muscular tissue. The utility and success of this ureter prosthesis has been confirmed in multiple testing of dogs which have survived more than a year with the prosthetic ureter in place.
    Type: Grant
    Filed: December 21, 1979
    Date of Patent: June 15, 1982
    Assignee: University of Utah
    Inventors: Donald J. Lyman, Richard G. Middleton
  • Patent number: 4173689
    Abstract: A blood and body-tissue compatible synthetic polymer having mechanical compliance properties matching that of body tissue, useful in prosthesis as vascular grafts, skin covering, small diameter body duct work, and similar tissue replacement materials. A block copolymer having suitable body and blood compatibility characteristics is dissolved in a solvent, yielding a solution having an approximate relative viscosity between the range of 100 to 1000. A clean mandrel is slowly dipped into the solution and slowly withdrawn, leaving a uniform coating of polymer solution over the forming surface of the mandrel. The coated mandrel is then immersed into a second, nonsolvent solution which is miscible with the first solvent. The resulting transfer of the nonsolvent solution into the polymer network, displacing the first solvent molecules, acts to precipitate the polymer in a physical form containing a uniform dispersion of voids throughout the polymer structure.
    Type: Grant
    Filed: February 3, 1976
    Date of Patent: November 6, 1979
    Assignee: University of Utah
    Inventors: Donald J. Lyman, Frank J. Fazzio