Patents by Inventor Alexander Lloyd MacKay

Alexander Lloyd MacKay 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: 6150815
    Abstract: A method of correcting for magnetic field inhomogeneity caused by various factors, such as implanted metal and air/tissue interfaces, in magnetic resonance imaging (MRI) is provided. Geometric distortion due to inhomogeneity in a static magnetic field B.sub.0 is corrected for by addition of a compensation gradient. The compensation gradient is applied in the slice selection direction Z, has a timing substantially identical to the standard frequency encoding gradient G.sub.x, and has an amplitude identical to the slice selection gradient G.sub.z that is applied during the initial RF excitation. Inhomogeneity in an RF field B.sub.1 is compensated for by utilizing an RF coil that is large enough in size as compared with a metal implant to make the volumetric percentage of the metal in the coil insignificant. Inhomogeneity in a gradient field G=(G.sub.x, G.sub.y, G.sub.z) is corrected for by a treatment of the most significant error factor G.sub.z that causes slice thickness error.
    Type: Grant
    Filed: April 9, 1998
    Date of Patent: November 21, 2000
    Assignee: The University of British Columbia
    Inventors: Dennis Lyle Janzen, Douglas George Connell, Alexander Lloyd MacKay, Qing-San Xiang