Patents by Inventor John T. Grayhack

John T. Grayhack 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: 4611594
    Abstract: Several versions of instruments are disclosed which are useful for the containment of calculi to minimize injury to surrounding tissue during removal and/or destruction of such calculi. In each embodiment a suitable grasping device is utilized to locate and grasp a stone (calculus) in a body passage or organ, such grasping device being used in combination with a catheter having an expandable and contractable distal end portion capable of receiving and substantially enclosing the stone to protect the surrounding tissue from injury that might otherwise be produced by the rough edges of the stone as it is extracted, or to shield such tissue as the stone is fragmented in situ and then contain the fragments as they are removed.
    Type: Grant
    Filed: April 11, 1984
    Date of Patent: September 16, 1986
    Assignee: Northwestern University
    Inventors: John T. Grayhack, Theodore V. Benderev