Patents by Inventor George Leung

George Leung 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).

  • Publication number: 20220003353
    Abstract: Composite materials with adjustable spectral properties comprised of IR-reflecting micro-domains overlaying an IR-transparent elastomeric matrix, and capable of dynamically controlling IR radiation transmission are described, as well as methods of fabrication thereof. Systems with capabilities to regulate IR radiation (including heat) transmission based thereon, and methods of regulating IR radiation transmission (including thermal regulation) using the same are also provided.
    Type: Application
    Filed: November 27, 2019
    Publication date: January 6, 2022
    Applicant: The Regents of the University of California
    Inventors: Alon A. Gorodetsky, Steven R. Jim, George Stiubianu, Erica Leung, Kyle Naughton, Priyam Patel, Maurizio Follador, Emil Karshalev
  • Publication number: 20210128231
    Abstract: An energy-transmitting therapeutic device having a hollow elongated assembly with a flexible tip at its distal end in which the hollow elongated assembly includes energy-transmitting elements and directional control elements. The directional control elements control the flexible tip such that it can pass through a lumen having a curve with a minimum radius of 1 cm and the energy-transmitting elements can deliver energy at an electromagnetic frequency of 300 KHz to 300 GHz.
    Type: Application
    Filed: October 29, 2020
    Publication date: May 6, 2021
    Inventors: Theodore Ormsby, George Leung, Gwo Jenn Shen
  • Patent number: 9326819
    Abstract: An ablation system which transmits radio frequency (RF) energy for the ablation of biological tissues has a transmission line and an RF antenna disposed at the distal portion of the transmission line. An RF signal generator supplies RF energy to the proximal end of the cable for transmission to the antenna, and an electrically tunable transformer is connected between the signal generator and the antenna. The transformer is tuned based on detection of the reflected power level from the antenna so as to reduce or minimize reflected power, thereby increasing RF energy coupling between the antenna and tissue.
    Type: Grant
    Filed: April 15, 2009
    Date of Patent: May 3, 2016
    Assignee: Medwaves, Inc.
    Inventors: Theodore C. Ormsby, Russell Chung, George Leung, Gwo Jenn Shen
  • Patent number: 8934989
    Abstract: An ablation device which transmits radio frequency (RF) energy for the ablation of biological tissues has elongate inner and outer coaxial conductors extending from a proximal portion to a distal portion. An RF antenna is disposed at the distal portion of the device and transmits RF energy for ablation of a tissue region to be treated. Reflection of energy from the tissue or the ablation point is reduced by providing multiple layers of dielectric media about the antenna, or by providing a gradual transition point from the conductors to the antenna tip, by means of a longitudinally stepped dielectric layer transformer.
    Type: Grant
    Filed: April 15, 2009
    Date of Patent: January 13, 2015
    Assignee: MedWaves, Inc.
    Inventors: Theodore C. Ormsby, Russell Chung, George Leung, Gwo Jenn Shen
  • Patent number: 8679106
    Abstract: A coaxial cable apparatus which transmits radio frequency (RF) energy for the ablation of biological tissues has inner and outer coaxial conductors extending substantially the entire length of the cable from a proximal end portion to a distal end portion. An RF antenna is disposed at the distal end portion of the cable and transmits RF energy for ablation of a tissue region to be treated. An angioplasty balloon is disposed over the RF antenna and communicates with a fluid supply and extraction passageway extending through the cable to allow the balloon to be inflated for an angioplasty procedure including tissue ablation, and to be deflated after the procedure is complete.
    Type: Grant
    Filed: July 1, 2008
    Date of Patent: March 25, 2014
    Assignee: Medwaves, Inc.
    Inventors: Theodore C. Ormsby, George Leung, Gwo Jenn Shen
  • Publication number: 20100268218
    Abstract: An ablation system which transmits radio frequency (RF) energy for the ablation of biological tissues has a transmission line and an RF antenna disposed at the distal portion of the transmission line. An RF signal generator supplies RF energy to the proximal end of the cable for transmission to the antenna, and an electrically tunable transformer is connected between the signal generator and the antenna. The transformer is tuned based on detection of the reflected power level from the antenna so as to reduce or minimize reflected power, thereby increasing RF energy coupling between the antenna and tissue.
    Type: Application
    Filed: April 15, 2009
    Publication date: October 21, 2010
    Applicant: MedWaves, Inc.
    Inventors: Theodore C. Ormsby, Russell Chung, George Leung, Gwo Jenn Shen
  • Publication number: 20100268219
    Abstract: An ablation device which transmits radio frequency (RF) energy for the ablation of biological tissues has elongate inner and outer coaxial conductors extending from a proximal portion to a distal portion. An RF antenna is disposed at the distal portion of the device and transmits RF energy for ablation of a tissue region to be treated. Reflection of energy from the tissue or the ablation point is reduced by providing multiple layers of dielectric media about the antenna, or by providing a gradual transition point from the conductors to the antenna tip, by means of a longitudinally stepped dielectric layer transformer.
    Type: Application
    Filed: April 15, 2009
    Publication date: October 21, 2010
    Applicant: MEDWAVES, INC.
    Inventors: Theodore C. Ormsby, Russell Chung, George Leung, Gwo Jenn Shen
  • Publication number: 20100004650
    Abstract: A coaxial cable apparatus which transmits radio frequency (RF) energy for the ablation of biological tissues has inner and outer coaxial conductors extending substantially the entire length of the cable from a proximal end portion to a distal end portion. An RF antenna is disposed at the distal end portion of the cable and transmits RF energy for ablation of a tissue region to be treated. An angioplasty balloon is disposed over the RF antenna and communicates with a fluid supply and extraction passageway extending through the cable to allow the balloon to be inflated for an angioplasty procedure including tissue ablation, and to be deflated after the procedure is complete.
    Type: Application
    Filed: July 1, 2008
    Publication date: January 7, 2010
    Applicant: MEDWAVES, INC.
    Inventors: Theodore C. Ormsby, George Leung, Gwo Jenn Shen
  • Publication number: 20080015570
    Abstract: A hollow coaxial cable adapted for conduction of radio frequency (RF) energy, particularly microwave energy, has a proximal end and a distal end and comprises coaxial inner and outer conductors extending substantially the entire length of the cable from the proximal end to a distal end portion of the cable with a dielectric medium disposed between the inner and outer conductors. The inner conductor comprises an elongated electrically conductive tubular member having a hollow, axially extending lumen, and the outer conductor comprises an elongated electrically conductive tubular member disposed in a substantially coaxial relationship over at least a portion of the inner conductor. An ablating member which delivers radio frequency energy, particularly microwave energy, to body tissue is disposed at a distal end portion of the cable.
    Type: Application
    Filed: July 23, 2007
    Publication date: January 17, 2008
    Inventors: Theodore Ormsby, George Leung, Gwo Shen, Peter Chu, Ming Law
  • Publication number: 20070066972
    Abstract: A radio frequency (RF) ablation catheter has a flexible distal end portion so that it can be deflected to position an antenna disposed in the distal end portion adjacent a tissue site to be treated. At least one electrical conductor is coupled to the antenna and extends through the catheter to the proximal end of the catheter to a connector at the proximal end of the catheter for connection to a power supply for the RF antenna. At least one electrode is disposed at the distal end portion of the catheter and electrically coupled to the proximal end connector for connection to a monitor. The electrode is of a flexible, electrically conductive material such as conductive polymer material. The electrode may be an electrocardiogram (ECG) electrode.
    Type: Application
    Filed: October 19, 2006
    Publication date: March 22, 2007
    Inventors: Theodore Ormsby, George Leung, Gwo Shen, Peter Chu
  • Publication number: 20060287649
    Abstract: A radio-frequency based catheter system and method for ablating biological tissues within the body vessel of a patient comprises a radio-frequency (“RF”) generator for selectively generating a high frequency RF energy signal in a deployable catheter having an RF transmission line, an RF antenna mounted on the distal portion of the catheter, and a temperature sensor also mounted on a distal portion of the catheter for detecting temperature adjacent an ablation site. A control system adjusts the RF energy signal so that the detected temperature is at or close to a selected temperature setting or within a selected temperature range.
    Type: Application
    Filed: June 30, 2006
    Publication date: December 21, 2006
    Inventors: Theodore Ormsby, George Leung, Gwo Shen, Peter Chu, Ming Fan Law
  • Publication number: 20060142752
    Abstract: A RF catheter system includes a catheter with a proximal portion, a distal portion having a distal end and a lumen extending from the proximal portion to the distal portion. Inner and outer coaxially aligned conductors extend within the catheter and are coaxial with the lumen. A deflectable catheter guide is disposed within the catheter lumen and extends proximally within the catheter lumen and terminates distally of the distal end of the catheter to define a biological ablation pathway. A radio-frequency antenna is disposed at the distal portion of the catheter and is in electrical communication with the inner and outer coaxially aligned conductors. The radio-frequency antenna is adaptable to receive and transmit radio-frequency energy for ablating biological tissue along the ablation pathway.
    Type: Application
    Filed: February 22, 2006
    Publication date: June 29, 2006
    Inventors: Theodore Ormsby, Ming-Fan Law, George Leung
  • Patent number: 5366870
    Abstract: Method for determining the presence of an aminotransferase (AT.sub.1), other than aspartate aminotransferase (AST), in a biological sample. The method includes contacting the sample with an amino donor substrate for AT.sub.1, an amino acceptor substrate for AT.sub.1, cysteine sulfinic acid (CSA) in excess, a second aminotransferase (AT.sub.2), different from AT.sub.1, in excess, and an indicator for the presence of sulfite ions, under conditions in which the concentration of said AT.sub.1 can be determined by the amount of the indicator which forms a detectable signal.
    Type: Grant
    Filed: April 2, 1993
    Date of Patent: November 22, 1994
    Assignee: Xytronyx, Inc.
    Inventors: Gerald Odstrchel, George Leung