Tissue ablation apparatus and method

• US 5,871,481 A
• Filed: 04/11/1997
• Issued: 02/16/1999
• Est. Priority Date: 04/11/1997
• Status: Expired due to Term

• Current Assignee: Project Trojan Intellectual Property Acquisition, LLC
• Original Assignee: Vidamed, Inc. (Medtronic Plc)
• Inventors: Hendrick, John N., Kannenberg, Donald P., Huntley, Scott P.
• Primary Examiner(s): COHEN, LEE S
• Application Number:
  US08/833,982
• Time in Patent Office: 676 Days
• Field of Search: 606/32, 606/34, 606/41, 606/45, 606/49, 607/99, 607/100, 607/105, 607/113
• US Class Current: 606/34
• CPC Class Codes: A61B 18/1206 Generators therefor
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00755 Resistance or impedance
• CPC Class Codes: A61B 2018/00875 Resistance or impedance

Abstract

A radio frequency tissue ablation apparatus for use on a horizontal support surface in connection with a medical procedure on a patient. A portable carrying case having a carrying handle is provided and is adapted to rest upon a horizontal surface. The portable carrying case has a cover with an inner surface and is movable between a generally vertical open position and a generally horizontal closed position when the portable carrying case is resting on the horizontal support surface. The portable carrying case has a keyboard and a primary display panel disposed adjacent the keyboard under the cover when the cover is in a closed position and is accessible visually and physically when the cover is in an open position. The primary display panel includes a plurality of groups of numerical indicia and a plurality of switches associated with at least certain of the groups of numerical indicia for establishing criteria for those certain groups of numerical indicia. The primary display panel includes an additional switch for selecting automatic or manual operation. A graphic display panel is carried by the inner surface of the cover. Electrical circuitry, including a radio frequency generator and a control computer, is disposed within the portable carrying case and is coupled to the keyboard, the primary display panel and the graphic display panel. The portable carrying case has a plurality of ports accessible externally in communication with the electrical circuitry in the portable carrying case. A probe is coupled to one of the ports carrying an electrode and is adapted to penetrate tissue.

Claims

1. A radio frequency tissue ablation apparatus for use on a horizontal support surface in connection with a medical procedure on a patient comprising a portable carrying case having a carrying handle, the portable carrying case being adapted to rest upon the horizontal surface, the portable carrying case having a cover with an inner surface and being movable between a generally vertical open position and a generally horizontal closed position when the portable carrying case is resting on the horizontal support surface, the portable carrying case having a keyboard and a primary display panel disposed adjacent the keyboard underlying the cover when the cover is in a closed position and being accessible visually and physically when the cover is in an open position, said primary display panel including a plurality of groups of indicia and a plurality of switches associated with at least certain of the groups of indicia for establishing criteria for those certain groups of indicia, said primary display panel including an additional switch for selecting manual or automatic operation, a graphic display panel carried by the inner surface of the cover, electrical circuitry including a radio frequency generator and a control computer disposed within the portable carrying case and coupled to said keyboard, said primary display panel and said graphic display panel, said portable carrying case having a plurality of ports accessible externally in communication with the electrical circuitry in the portable carrying case and a probe coupled to one of the ports carrying an electrode adapted to penetrate tissue.

2. Apparatus as in claim 1 wherein said primary display panel has legends overlying the groups of indicia and wherein said primary display panel is backlit.

3. Apparatus as in claim 1 wherein said primary display panel is inclined at an angle with respect to the keyboard to improve visibility so that a single person can perform an ablation procedure while operating the controls.

4. Apparatus as in claim 1 wherein said electrical circuitry includes impedance measuring means for monitoring the impedance in the tissue being ablated and including means for ascertaining when a predetermined impedance in the tissue has been reached and means for automatically reducing the radio frequency power applied to the electrode without terminating the power to the electrical circuitry when the predetermined impedance has been reached.

5. Apparatus as in claim 4 wherein said electrical circuitry includes means for applying radio frequency power at a level to avoid creation of a high impedance condition after a predetermined impedance has been reached.

6. Apparatus as in claim 4 wherein said electrical circuitry includes means for permitting the predetermined impedance to prevail for only a short period of time.

7. Apparatus as in claim 4 wherein said impedance measuring means includes means for calculating impedance and displaying impedance measured on the graphic display panel with respect to time.

8. Apparatus as in claim 1 together with a foot pedal connected to one of the ports of the portable carrying case for controlling certain operations of the electrical circuitry.

9. Apparatus as in claim 1 together with a grounding pad adapted to be placed in contact with the patient and connected to one of the ports of the portable carrying case.

10. Apparatus as in claim 1 together with a touch pad mounted in the portable carrying case adjacent the keyboard for supplying information to the control computer.

11. A method for ablating tissue of a patient in a medical procedure by the use of a portable carrying case adapted to rest upon a horizontal support surface, the portable carrying case having a cover with an inner surface and being movable between a generally vertical open position and a generally horizontal closed position when the carrying case is resting on the horizontal support surface, the carrying case having a keyboard and a primary display panel disposed adjacent the keyboard underlying the cover when the cover is in a closed position and being accessible visually and physically when the cover is in an open position, a graphic display panel carried by the inner surface of the cover, said primary display panel including a plurality of groups of indicia and a plurality of switches associated with at least certain of the groups of indicia for establishing criteria for those certain groups of indicia, electrical circuitry including a radio frequency generator and a control computer disposed within the portable carrying case and coupled to the keyboard, the primary display panel and to the graphic display panel and by the use of a probe carrying an electrode adapted to penetrate tissue, said primary display panel having control switches for selecting automatic or manual operation, the method comprising setting parameters for the medical procedure utilizing the keyboard and said switches, performing the medical procedure to supply radio frequency energy from the radio frequency generator to the electrode of the probe to cause ablation of tissue in the patient while operating the switches and alternatively selecting manual or automatic operation for supplying radio frequency energy to the electrode during the medical procedure.

12. A method as in claim 11 together with the step of ascertaining the impedance in the tissue being ablated and ascertaining when a predetermined impedance has been reached and automatically reducing the radio frequency power applied to the electrode when the predetermined impedance has been reached without terminating power to the electrical circuitry.

13. A method as in claim 12 together with the step of applying radio frequency power at a level to avoid creating a high impedance condition after the predetermined impedance has been reached.

14. A method as in claim 12 together with the step of permitting a high impedance condition to prevail for only a short period of time.

15. A radio frequency tissue ablation apparatus for use on a horizontal support surface in connection with a medical procedure on a patient comprising a portable carrying case having a carrying handle, the portable carrying case being adapted to rest upon the horizontal surface, the portable carrying case having a cover with an inner surface and being movable through an angle of at least approximately 90°

between an open position and a generally horizontal closed position when the portable carrying case is resting on the horizontal support surface, the portable carrying case having a primary display panel underlying the cover when the cover is in a closed position and being accessible visually and physically when the cover is in an open position, said primary display panel including a plurality of groups of indicia and a plurality of switches associated with at least certain of the groups of indicia for establishing criteria for those certain groups of indicia, said primary display panel including an additional switch for selecting manual or automatic operation, electrical circuitry including a radio frequency generator and a control computer disposed within the portable carrying case and coupled to said primary display panel, said portable carrying case having a plurality of ports accessible externally in communication with the electrical circuitry in the portable carrying case and a probe coupled to one of the ports carrying an electrode adapted to penetrate tissue.

16. Apparatus as in claim 15 wherein said primary display panel has legends overlying the groups of indicia and wherein said primary display panel is backlit.

17. Apparatus as in claim 15 wherein said primary display panel is inclined at an angle with respect to horizontal when the portable carrying case is resting on the horizontal support surface to improve visibility so that a single person can perform an ablation procedure while operating the controls.

18. Apparatus as in claim 15 wherein said electrical circuitry includes impedance measuring means for monitoring the impedance in the tissue being ablated and including means for ascertaining when a predetermined impedance in the tissue has been reached and means for automatically reducing the radio frequency power applied to the electrode without terminating the power to the electrical circuitry when the predetermined impedance has been reached.

19. Apparatus as in claim 18 wherein said electrical circuitry includes means for applying radio frequency power at a level to avoid creation of a high impedance condition after a predetermined impedance has been reached.

20. Apparatus as in claim 15 together with a foot pedal connected to one of the ports of the portable carrying case for controlling certain operations of the electrical circuitry.

21. Apparatus as in claim 15 together with a grounding pad adapted to be placed in contact with the patient and connected to one of the ports of the portable carrying case.