Patents by Inventor Chad Q. Cai

Chad Q. Cai 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: 9186499
    Abstract: Grounding of a shield that is located in an implantable medical lead may be done in many ways. The ground pathway may couple to the shield at a point that is outside of a header of an implantable medical device to which the implantable medical lead is attached. The ground pathway may couple to the shield at a point that is within the header of the implantable medical device. The ground pathway may terminate at the metal can of the implantable medical device. As another option, the ground pathway may terminate at a ground plate that is mounted to the header. The ground pathway may be direct current coupled from the shield to the can or ground plate. Alternatively, the ground pathway may include one or more capacitive couplings that provide a pathway for induced radio frequency current.
    Type: Grant
    Filed: April 27, 2010
    Date of Patent: November 17, 2015
    Assignee: MEDTRONIC, INC.
    Inventors: James M. Olsen, Michael R. Klardie, Richard T. Stone, Chad Q. Cai, Spencer M. Bondhus, Mark J. Conroy, Timothy R. Abraham
  • Publication number: 20140350654
    Abstract: Implantable medical leads include a shield that is guarded at a termination by having a first portion and a second portion of the shield, where the first portion is between a termination of the shield at the second portion and an inner insulation layer that surrounds the filars. The first portion may reduce the coupling of RF energy from the termination of the shield at the second portion to the filars. The first and second portions may be part of a continuous shield, where the first and second portions are separated by an inversion of the shield. The first and second portions may instead be separate pieces. The first portion may be noninverted and reside between the termination at the second portion and the inner layers, or the first portion may be inverted to create first and second sub-portions. The shield termination at the second portion is between the first and second sub-portions.
    Type: Application
    Filed: August 11, 2014
    Publication date: November 27, 2014
    Inventors: James M. Olsen, Michael Robert Klardie, Richard T. Stone, Chad Q. Cai, Spencer M. Bondhus, Mark J. Conroy, Timothy R. Abraham
  • Publication number: 20140345132
    Abstract: A shield located within an implantable medical lead may be terminated in various ways at a metal connector. The shield may be terminated by various joints including butt, scarf, lap, or other joints between insulation layers surrounding the lead and an insulation extension. The shield may terminate with a physical and electrical connection to a single metal connector. The shield may terminate with a physical and electrical connection by passing between an overlapping pair of inner and outer metal connectors. The metal connectors may include features such as teeth or threads that penetrate the insulation layers of the lead. The shield may terminate with a physical and electrical connection by exiting a jacket of a lead adjacent to a metal connector and lapping onto the metal connector.
    Type: Application
    Filed: July 21, 2014
    Publication date: November 27, 2014
    Inventors: Bruce R. Mehdizadeh, Brian T. Stolz, Michael Robert Klardie, James M. Olsen, Michael J. Kerns, Richard T. Stone, Chad Q. Cai, Spencer M. Bondhus, Mark J. Conroy, Timothy R. Abraham
  • Patent number: 8897890
    Abstract: An implantable system that includes a lead and an implantable signal generator wherein the plurality of electrical contacts and the plurality of insulating regions on the lead, and the plurality of electrical connectors and the plurality of electrical insulators in the connector block are configured so that each of the plurality of electrical contacts form operable connections to the electronic circuitry through each of the plurality of electrical connector, and the insulating regions and the electrical insulators electrically isolate adjacent operable connections. Leads, and methods are also disclosed.
    Type: Grant
    Filed: April 29, 2013
    Date of Patent: November 25, 2014
    Assignee: Medtronic, Inc.
    Inventors: James A. Alexander, James M. Olsen, Chad Q. Cai, Richard T. Stone, James G. Skakoon, Kristin J. Malekkhosravi
  • Patent number: 8805534
    Abstract: Grounding of a shield that is located in an implantable medical lead may be done in many ways. The shield may be grounded directly to tissue from the lead body at one or more points along the lead body. The pathway for grounding may be a direct current pathway or be capacitively coupled. The pathway for grounding may utilize an exposed or nearly exposed shield at one or more points along the lead body. A jacket forming the lead body may have an outer layer removed at these points to provide the RF pathway to ground. Alternatively, the jacket may be doped with conductive particles at these points. Metal conductors such as ring electrodes and/or lead anchors may be attached to the lead at one or more points to provide the RF pathway to ground.
    Type: Grant
    Filed: April 28, 2010
    Date of Patent: August 12, 2014
    Assignee: Medtronic, Inc.
    Inventors: James M. Olsen, Michael R. Klardie, Richard T. Stone, Chad Q. Cai, Spencer M. Bondhus, Mark J. Conroy, Timothy R. Abraham
  • Patent number: 8788061
    Abstract: A shield located within an implantable medical lead may be terminated in various ways at a metal connector. The shield may be terminated by various joints including butt, scarf, lap, or other joints between insulation layers surrounding the lead and an insulation extension. The shield may terminate with a physical and electrical connection to a single metal connector. The shield may terminate with a physical and electrical connection by passing between an overlapping pair of inner and outer metal connectors. The metal connectors may include features such as teeth or threads that penetrate the insulation layers of the lead. The shield may terminate with a physical and electrical connection by exiting a jacket of a lead adjacent to a metal connector and lapping onto the metal connector.
    Type: Grant
    Filed: April 27, 2010
    Date of Patent: July 22, 2014
    Assignee: Medtronic, Inc.
    Inventors: Bruce R. Mehdizadeh, Brian T. Stolz, Michael R. Klardie, Michael J. Kern, James M. Olsen, Richard T. Stone, Chad Q. Cai, Spencer M. Bondhus, Mark J. Conroy, Timothy R. Abraham
  • Publication number: 20130245735
    Abstract: An implantable system that includes a lead and an implantable signal generator wherein the plurality of electrical contacts and the plurality of insulating regions on the lead, and the plurality of electrical connectors and the plurality of electrical insulators in the connector block are configured so that each of the plurality of electrical contacts form operable connections to the electronic circuitry through each of the plurality of electrical connector, and the insulating regions and the electrical insulators electrically isolate adjacent operable connections. Leads, and methods are also disclosed.
    Type: Application
    Filed: April 29, 2013
    Publication date: September 19, 2013
    Applicant: Medtronic, Inc.
    Inventors: James A. Alexander, James M. Olsen, Chad Q. Cai, Richard T. Stone, James G. Skakoon, Kristin J. Schneider
  • Publication number: 20130245736
    Abstract: An implantable system that includes a lead and an implantable signal generator wherein the plurality of electrical contacts and the plurality of insulating regions on the lead, and the plurality of electrical connectors and the plurality of electrical insulators in the connector block are configured so that each of the plurality of electrical contacts form operable connections to the electronic circuitry through each of the plurality of electrical connector, and the insulating regions and the electrical insulators electrically isolate adjacent operable connections. Leads, and methods are also disclosed.
    Type: Application
    Filed: April 29, 2013
    Publication date: September 19, 2013
    Applicant: Medtronic, Inc.
    Inventors: James A. Alexander, James M. Olsen, Chad Q. Cai, Richard T. Stone, James G. Skakoon, Kristin J. Schneider
  • Patent number: 8433422
    Abstract: An implantable system that includes a lead and an implantable signal generator wherein the plurality of electrical contacts and the plurality of insulating regions on the lead, and the plurality of electrical connectors and the plurality of electrical insulators in the connector block are configured so that each of the plurality of electrical contacts form operable connections to the electronic circuitry through each of the plurality of electrical connector, and the insulating regions and the electrical insulators electrically isolate adjacent operable connections. Leads, and methods are also disclosed.
    Type: Grant
    Filed: April 20, 2007
    Date of Patent: April 30, 2013
    Assignee: Medtronic, Inc.
    Inventors: James A. Alexander, James M. Olsen, Chad Q. Cai, Richard T. Stone, James G. Skakoon, Kristin J. Schneider
  • Publication number: 20120130461
    Abstract: Radiopaque markers represent that a lead is suitable for a particular medical procedure such as a magnetic resonance image scan and are added to the lead or related device. The markers may be added after implantation of the lead in various ways including suturing, gluing, crimping, or clamping a radiopaque tag to the lead or to the device. The markers may be added by placing a radiopaque coil about the lead, and the radiopaque coil may radially contract against the lead to obtain a fixed position. The markers may be added by placing a polymer structure onto the lead where the polymer structure includes a radiopaque marker within it. The polymer structure may include a cylindrical aperture that contracts against the lead to fix the position of the structure. The polymer structure may form a lead anchor that includes suture wings that can be sutured to the lead.
    Type: Application
    Filed: April 28, 2010
    Publication date: May 24, 2012
    Applicant: MEDTRONIC, INC.
    Inventors: James M. Olsen, Michael R. Klardie, Richard T. Stone, Chad Q. Cai, Spencer M. Bondhus, Mark J. Conroy, Timothy R. Abraham, Bruce R. Mehdizadeh, Michael J. Kern, Jay K. Lahti
  • Publication number: 20120046722
    Abstract: Implantable medical leads are shielded with a braided shield that surrounds an inner layer of insulation. An outer layer of insulation may also surround the shield. The shield is designed with parameters that limit the passage of radio frequency energy, particularly in the magnetic resonance imaging spectrum, to filars that are surrounded by the inner layer of insulation. The braided shield has a plurality of parameters and corresponding ranges. The parameters include one or more of braid angle, wire size, number of wires wound per direction, number of wires in a bundle, wire spacing in an axial dimension, ultimate tensile strength, cross-sectional wire shape, material, and distance from termination to a nearest electrode. Additional parameters of the lead related to the shielding also include one or more of inner insulation thickness, and outer insulation thickness.
    Type: Application
    Filed: April 27, 2010
    Publication date: February 23, 2012
    Applicant: MEDTRONIC, INC.
    Inventors: James M. Olsen, Michael R. Klardie, Richard T. Stone, Chad Q. Cai, Spencer M. Bondhus, Mark J. Conroy, Timothy R. Abraham
  • Publication number: 20120041528
    Abstract: A shield located within an implantable medical lead may be terminated in various ways at a metal connector. The shield may be terminated by various joints including butt, scarf, lap, or other joints between insulation layers surrounding the lead and an insulation extension. The shield may terminate with a physical and electrical connection to a single metal connector. The shield may terminate with a physical and electrical connection by passing between an overlapping pair of inner and outer metal connectors. The metal connectors may include features such as teeth or threads that penetrate the insulation layers of the lead. The shield may terminate with a physical and electrical connection by exiting a jacket of a lead adjacent to a metal connector and lapping onto the metal connector.
    Type: Application
    Filed: April 27, 2010
    Publication date: February 16, 2012
    Applicant: Medtronic, Inc
    Inventors: Bruce R. Mehdizadeh, Brian T. Stolz, Michael R. Klardie, Michael J. Kern, James M. Olsen, Richard T. Stone, Chad Q. Cai, Spencer M. Bondhus, Mark J. Conroy, Timothy R. Abraham
  • Publication number: 20120035695
    Abstract: Grounding of a shield that is located in an implantable medical lead may be done in many ways. The ground pathway may couple to the shield at a point that is outside of a header of an implantable medical device to which the implantable medical lead is attached. The ground pathway may couple to the shield at a point that is within the header of the implantable medical device. The ground pathway may terminate at the metal can of the implantable medical device. As another option, the ground pathway may terminate at a ground plate that is mounted to the header. The ground pathway may be direct current coupled from the shield to the can or ground plate. Alternatively, the ground pathway may include one or more capacitive couplings that provide a pathway for induced radio frequency current.
    Type: Application
    Filed: April 27, 2010
    Publication date: February 9, 2012
    Inventors: James M. Olsen, Michael R. Klardie, Richard T. Stone, Chad Q. Cai, Spencer M. Bondhus, Mark J. Conroy, Timothy R. Abraham
  • Publication number: 20120035694
    Abstract: Grounding of a shield that is located in an implantable medical lead may be done in many ways. The shield may be grounded directly to tissue from the lead body at one or more points along the lead body. The pathway for grounding may be a direct current pathway or be capacitively coupled. The pathway for grounding may utilize an exposed or nearly exposed shield at one or more points along the lead body. A jacket forming the lead body may have an outer layer removed at these points to provide the RF pathway to ground. Alternatively, the jacket may be doped with conductive particles at these points. Metal conductors such as ring electrodes and/or lead anchors may be attached to the lead at one or more points to provide the RF pathway to ground.
    Type: Application
    Filed: April 28, 2010
    Publication date: February 9, 2012
    Applicant: Medtronic, Inc.
    Inventors: James M. Olsen, Michael R. Klardie, Richard T. Stone, Chad Q Cai, Spencer M. Bondhus, Mark J. Conroy, Timothy R. Abraham
  • Publication number: 20120035696
    Abstract: A shield located within an implantable medical lead may be terminated in various ways. The shield may be terminated by butt, scarf, lap, or other joints between insulation layers surrounding the lead and an insulation extension. For lap joints, a portion of an outer insulation layer may be removed and a replacement outer insulation layer is positioned in place of the removed outer insulation layer, where the replacement layer extends beyond an inner insulation layer and the shield. The replacement layer may also lap onto a portion of the insulation extension. Barbs may be located between the replacement layer and the inner insulation layer or the insulation extension. The shield wires have ends at the termination point that may be folded over individually or may be capped with a ring located within one of the insulation layers of the jacket.
    Type: Application
    Filed: April 27, 2010
    Publication date: February 9, 2012
    Applicant: Medtronic, Inc.
    Inventors: Michael J. Kern, James M. Olsen, Michael R. Klardie, Richard T. Stone, Chad Q. Cai, Spencer M. Bondhus, Mark J. Conroy, Timothy R. Abraham, Brian T. Stolz
  • Publication number: 20120035616
    Abstract: An implantable medical lead has a torsional stiffness and is rotationally coupled to a stylet. Applying rotation directly to the lead in turn causes rotation of the stylet. Where the stylet has a bent tip for purposes of steering the lead, the rotation applied to the lead rotates the bent tip so that the lead can be steered by rotating the lead rather than rotating a hub of the stylet. The rotational coupling may be achieved through one or more features provided for the lead and/or the stylet, such as a feature within a lumen of the lead that mates to a feature along the stylet or a feature of the stylet hub that engages the proximal end of the lead. The torsional stiffness of the lead may be provided by adding a feature within the lead body, such as a braided metal wire or an overlapping foil.
    Type: Application
    Filed: April 27, 2010
    Publication date: February 9, 2012
    Applicant: Medtronic, Inc.
    Inventors: James M. Olsen, Michael R. Klardie, Richard T. Stone, Chad Q. Cai, Spencer M. Boudhus, Mark J. Conway, Timothy R. Abraham
  • Publication number: 20080262582
    Abstract: An implantable system that includes a lead and an implantable signal generator wherein the plurality of electrical contacts and the plurality of insulating regions on the lead, and the plurality of electrical connectors and the plurality of electrical insulators in the connector block are configured so that each of the plurality of electrical contacts form operable connections to the electronic circuitry through each of the plurality of electrical connector, and the insulating regions and the electrical insulators electrically isolate adjacent operable connections. Leads, and methods are also disclosed.
    Type: Application
    Filed: April 20, 2007
    Publication date: October 23, 2008
    Applicant: MEDTRONIC, INC.
    Inventors: James A. Alexander, James M. Olsen, Chad Q. Cai, Richard T. Stone, James G. Skakoon, Kristin J. Schneider
  • Publication number: 20080262585
    Abstract: An implantable medical system that includes an implantable electrical lead having a lead body having a connector portion wherein at least the connector portion of the lead body has an axial cross section that is substantially non-circular; and a connector block that is configured to be operably coupled to the implantable electrical lead, wherein the connector block includes a lumen having an inner surface that is configured to be complementary to the outer surface of at least the connector portion of the lead body. Leads and connector blocks are also discussed.
    Type: Application
    Filed: April 20, 2007
    Publication date: October 23, 2008
    Applicant: MEDTRONIC, INC.
    Inventors: James A. Alexander, James M. Olsen, Chad Q. Cai, Richard T. Stone, James G. Skakoon, Kristin J. Schneider
  • Patent number: 6953332
    Abstract: Improved dip coating methods and mandrels for forming polymer leaflets and valve prostheses generally involve one or more features on the mandrel that facilitate the processing. The mandrel has a top surface and an outer surface comprising a plurality of ridges and contoured surfaces extending to the ridges. An edge on the mandrel separates the top surface and the contoured surfaces, with the mandrel edge corresponding to the free edge of the leaflet. In preferred embodiments, the edge separating the top surface from the contoured surfaces is sharp. The polymer formed on the top surface can be efficiently separated from the remaining portions of the polymer structure to form the free edges of the leaflets.
    Type: Grant
    Filed: November 28, 2000
    Date of Patent: October 11, 2005
    Assignee: St. Jude Medical, Inc.
    Inventors: James L. Kurk, Chad Q. Cai, Steven D. Kruse, Yi-Ren Woo
  • Patent number: 6881224
    Abstract: An improved method for testing a stent for a prosthetic valve includes applying a load with a fluid against a stented test structure in a backward direction with the stented test structure substantially blocking the flow of the fluid. The stented test structure includes a stent and a flexible membrane extending within the lumen defined by the stent with the flexible membrane having a plurality of contours connecting to the stent along the scallops. A corresponding testing apparatus includes a cyclic pressure applicator, a conduit connected to the cyclic pressure applicator, and a stented test structure mounted within the conduit to receive cyclic fluid pressures from the cyclic pressure applicator. The stented test structure includes a stent and a flexible membrane extending within the lumen defined by the stent. The flexible membrane substantially blocks flow of the fluid in a backward direction and does not fully open upon application of the fluid pressure in a forward direction.
    Type: Grant
    Filed: December 28, 2001
    Date of Patent: April 19, 2005
    Assignee: St. Jude Medical, Inc.
    Inventors: Steven D. Kruse, Chad Q. Cai