High frequency power source

• US 20040138653A1
• Filed: 09/09/2003
• Published: 07/15/2004
• Est. Priority Date: 12/28/2000
• Status: Active Grant

• Current Assignee: Senorx Incorporated (Becton, Dickinson & Co)
• Original Assignee: Senorx Incorporated (Becton, Dickinson & Co)
• Inventors: Lubock, Paul, Quick, Richard L., Dabney, James Huntington, Sawicz, Conrad, Kussman, Dan
• Granted Patent: US 7,175,618 B2
• Time in Patent Office: Days
• US Class Current: 606/34
• CPC Class Codes: A61B 18/1206 Generators therefor
• CPC Class Codes: A61B 18/1233 with circuits for assuring patient safety
• CPC Class Codes: A61B 18/16 Indifferent or passive electrodes for grounding
• CPC Class Codes: A61B 2018/00601 Cutting
• CPC Class Codes: A61B 2018/00607 Coagulation and cutting with the same instrument
• CPC Class Codes: A61B 2018/00666 using a threshold value
• CPC Class Codes: A61B 2018/00702 Power or energy
• CPC Class Codes: A61B 2018/00726 Duty cycle
• CPC Class Codes: A61B 2018/00827 Current
• CPC Class Codes: A61B 2018/00875 Resistance or impedance
• CPC Class Codes: A61B 2018/00892 Voltage
• CPC Class Codes: A61B 2018/00898 Alarms or notifications created in response to an abnormal condition
• CPC Class Codes: A61B 2018/0094 Types of switches or controllers
• CPC Class Codes: A61B 2018/1213 creating an arc
• CPC Class Codes: A61B 2018/1266 with DC current output
• CPC Class Codes: A61B 2018/1286 having a specific transformer
• CPC Class Codes: A61B 2018/162 located on the probe body

Abstract

A high frequency electrosurgical power generator configured to produce electrical power at a frequency of about 1 to about 14 MHz and preferably having an essentially sinusoidal waveform with a voltage level up to 1,000 Vrms, and a current level up to 5 Amps. The output of the high frequency electrosurgical power generator is connected to an electrosurgical tool configured to receive the voltage and current produced by the electrosurgical power generator and deliver the voltage and current to an electrosurgical site. The output of the electrosurgical generator preferably is an essentially sinusoid waveform with a frequency between about 3 MHz and about 8 MHz, up to about 700 volts rms, up to about 2 amps, with a total power of up to 1,000 watts.

Claims

1. A high frequency electrosurgical system comprising:

a. an electrical power generator configured to produce electrical power at a frequency of about 1 to about 14 MHz; and

b an electrosurgical tool configured to receive the electrical power from the generator and deliver the power to an electrosurgical site.

2. The system of claim 1 wherein the electrical power produced has an essentially sinusoidal waveform.

3. A system as defined in claim 1, further comprising a distal interface pod in communication with the power generator to receive voltage and current, configured to present a desired load to the power generator, and to monitor the voltage and current received from the power generator and deliver the voltage and current to the electrosurgical tool.

4. A system as defined in claim 3, wherein the pod is located in proximity to the electrosurgical tool.

5. A system as defined in claim 1, wherein the high frequency is between about 3 MHz and about 8 MHz.

6. A system as defined in claim 1, wherein the high frequency is about 3.4 MHz to about 5 MHz.

7. A system as defined in claim 1, wherein the power generator further comprises:

a control unit configured to generate a control signal;

a splitter, in communication with the control circuit and configured to produce a plurality of signals that are duplicates of the control signal;

a plurality of power amplifiers in communication with the plurality of signals that are duplicates of the control signal, configured to produce a high powered output signal in response to the control signal; and

a power combiner connected to the plurality of high powered output signals of the plurality of power amplifiers and configured to sum the plurality of high powered output signals and produce a single high powered output.

8. A system as defined in claim 1, wherein the power generator further comprises:

a feedback circuit configured to accept user inputs and at least one sense circuit signal, and to output a feedback modified control signal;

and

a signal generator configured to accept the user signal input and feedback control signals, and to output a signal generator control signal in response, wherein the control signal is a low power representation of the desired output of the power generator.

9. A system as defined in claim 8, wherein the at least one sense circuit signal comprises a signal sensing the current delivered by the electrosurgical tool to the patient.

10. A system as defined in claim 8, wherein the at least one sense circuit signal comprises a signal sensing the voltage delivered by the electrosurgical tool to the patient.

11. A system as defined in claim 1 further comprising a remote switch configured to turn the output of the power generator on and off.

12. A high frequency electrosurgical generator comprising:

a control unit configured to generate a control signal;

at least one voltage controlled electrical power generating unit configured to produce a high frequency current having an essentially sinusoidal waveform having a total harmonic distortion of less than 5%.

13. A high frequency electrosurgical generator as defined in claim 12, further comprising:

a splitter, in communication with the control circuit and configured to produce a plurality of duplicates of the control signal;

a power amplifier in communication with each of the plurality of duplicates of the control signal, the power amplifiers configured to produce a high powered output signal in response to the control signal; and

a power combiner connected to each of the high powered output signals of the power amplifiers and configured to sum the plurality of high powered output signals and produce a single high powered output.

14. A high frequency electrosurgical generator as defined in claim 13, wherein the plurality of duplicates of the control signal are four duplicates.

15. A high frequency electrosurgical generator as defined in claim 14, wherein there are four power amplifiers, one each connected to each of the four duplicates of the control signal.

16. A high frequency electrosurgical generator as defined in claim 12, wherein the control unit further comprises:

a set of user inputs configured to receive selection inputs desired by a user and output a user command signal;

a feedback circuit in communication with the user inputs and a distal interface pod, and configured to accept the user command signals and at least one sense circuit signals from the distal interface pod, and to output a feedback control signal in response to user command sense circuit signals; and

a signal generator in communication with the user inputs and the feedback circuit, and configured to accept the user command and feedback control signals, and to output a control signal in response to the user command and feedback control signals, wherein the control signal is a low power representation of the desired output of the power generator.

17. A high frequency electrosurgical generator as defined in claim 16, wherein the at least one sense circuit signal comprises a signal sensing the current delivered by the electrosurgical tool to the patient.

18. A high frequency electrosurgical generator as defined in claim 16, wherein the at least one sense circuit signal comprises a signal sensing the voltage delivered by the electrosurgical tool to the patient.

19. A high frequency electrosurgical generator as defined in claim 16, wherein the signal generator further comprises:

an oscillator configured to output a periodic waveform;

a low pass filter connected to the output of the oscillator, configured to receive the periodic waveform and to output essentially a sinusoidal waveform at the same frequency as the periodic waveform;

a voltage controlled amplifier connected to the output of the low pass filter and in communication with the feedback circuit, configured to receive the sinusoidal waveform and output an amplified sinusoidal waveform, wherein the sinusoidal waveform amplitude is varied in response to the feedback control signal;

a filter connected to the output of the voltage controlled amplifier, configured to receive the amplified sinusoidal waveform and output a filtered amplified waveform wherein any harmonics are attenuated;

a safety switch connected to the output of the filter and in communication with the user controls, configured to pass or block the filtered amplified waveform in response to an output received from user controls; and

a buffer connector to the output of the safety switch, configured to accept the filtered amplified waveform passed by the safety switch and to output a control signal.

20. A high frequency electrosurgical generator as defined in claim 19, wherein the periodic waveform is a sine wave.

21. A high frequency electrosurgical generator as defined in claim 19, wherein the periodic waveform is a square wave.

22. A high frequency electrosurgical generator as defined in claim 12, further comprising a remote switch in communication with the control unit, configured to turn the output of the power generator on and off.

23. A high frequency electrosurgical generator as defined in claim 12, wherein the control signal is a sinusoidal waveform having a frequency between about 1 MHz and about 14 MHz .

24. A high frequency electrosurgical generator as defined in claim 12, wherein the control signal is a sinusoidal waveform having a frequency of about 3 MHz to about 8 MHz.

25. A high frequency electrosurgical generator as defined in claim 12, wherein the control signal is a sinusoidal waveform having a frequency of about 3.4 MHz to about 5 MHz.

26. A high frequency electrosurgical generator as defined in claim 12, wherein the waveform for use with an electrosurgical tool is a sinusoidal waveform having a frequency between about 1 MHz and about 10 MHz.

27. A high frequency electrosurgical generator as defined in claim 12, wherein the waveform for use with an electrosurgical tool is a sinusoidal waveform having a frequency of about 3 MHz to about 8 MHz.

28. A high frequency electrosurgical generator as defined in claim 12, wherein the waveform for use with an electrosurgical tool is a sinusoidal waveform having a frequency of about 3.4 MHz to about 5 MHz.

29. A high frequency electrosurgical generator as defined in claim 12, wherein the waveform for use with an electrosurgical tool may be up to 1,000 watts.

30. A high frequency electrosurgical generator as defined in claim 12, wherein the waveform for use with an electrosurgical tool may be up to 700 volts rms.

31. A high frequency electrosurgical generator as defined in claim 12, wherein the waveform for use with an electrosurgical tool may be up to 5 amps of current.

32. A method of using a high frequency generator for cutting tissue, the method comprising:

a. generating a high frequency, essentially sinusoidal waveform; and

b. applying the waveform to an electrosurgical tool used to cut heterogeneous tissue.

33. A method as defined in claim 32, wherein the essentially sinusoidal waveform has a frequency between about 1 MHz and about 14 MHz.

34. A method as defined in claim 32, wherein the essentially sinusoidal waveform has a frequency of about 3 MHz to about 8 MHz.

35. A method as defined in claim 32, wherein the essentially sinusoidal waveform has a frequency of about 3.4 MHz to about 5 MHz.

36. A method as defined in claim 32, wherein the essentially sinusoidal waveform has a power level of up to 1,000 watts.

37. A method as defined in claim 32, wherein the essentially sinusoidal waveform has a power level of about 500 watts to about 1,000 watts.

38. A method as defined in claim 32, wherein the essentially sinusoidal waveform has a voltage level of up to 700 volts rms.

39. A method as defined in claim 32 wherein the essentially sinusoidal waveform has a voltage level of about 300 volts to about 600 volts.

40. A method as defined in claim 32, wherein the essentially sinusoidal waveform has a current capacity of up to 5 amps.

41. A method of generating a high frequency signal for use in an electrosurgical system, the method comprising:

a. generating a high frequency control signal;

b. applying the control signal to at least one power delivery unit configured to produce a high power waveform in response to the control signal;

c. filtering the high power waveform to produce an essentially sinusoidal output waveform; and

d. adjusting the control signal in response to sensing of desired waveform parameters at an electrosurgical tool.

42. A method as defined in claim 41, wherein the output waveform is a sinusoidal waveform with a frequency between about 1 MHz to and about 14 MHz.

43. A method as defined in claim 41, wherein the output waveform is a sinusoidal waveform with a frequency of about 3 MHz to about 8 MHz.

44. A method as defined in claim 41, wherein the output waveform is a sinusoidal waveform with a frequency of about 3.4 MHz to about 5 MHz.

45. A method as defined in claim 41, wherein the output waveform is a sinusoidal waveform with a power level of up to 1,000 watts.

46. A method as defined in claim 41, wherein the output waveform has a power level of about 500 watts to about 1,000 watts.

47. A method as defined in claim 41, wherein the output waveform is a sinusoidal waveform with a voltage level of up to 700 volts rms.

48. A method as defined in claim 41 wherein the output waveform has a voltage level of about 300 volts to about 600 volts.

49. A method as defined in claim 41, wherein the output waveform is a sinusoidal waveform with a current capacity of up to 5 amps.

50. A method as defined in claim 41, wherein the output waveform has any out of band frequencies attenuated at least 6 dB.

51. A high frequency electrosurgical generator comprising:

a control unit configured to generate a control signal;

a power delivery unit configured to receive the control signal and generate electrical power at a frequency of about 1 MHz to about 14 MHz suitable for use with an electrosurgical tool.

52. A high frequency electrosurgical generator as defined in claim 51, further comprising:

a splitter, in communication with the control unit and configured to produce a plurality of duplicates of the control signal;

a power amplifier in communication with each of the plurality of duplicates of the control signal, the power amplifiers configured to produce electrical power in response to the control signal; and

a power combiner connected to each of the electrical power output of the power amplifiers and configured to sum the plurality of the electrical power output of the power amplifiers and produce a single electrical power output.

53. A high frequency electrosurgical generator as defined in claim 52, wherein the plurality of duplicates of the control signal are four duplicates.

54. A high frequency electrosurgical generator as defined in claim 52, wherein there are four power amplifiers, one each connected to each of the four duplicates of the control signal.

55. A high frequency electrosurgical generator as defined in claim 51, wherein the control unit further comprises:

a set of user inputs configured to receive selection inputs desired by a user and output a user command signal;

a feedback circuit in communication with the user inputs and a distal interface pod, and configured to accept the user command signal and at least one sense circuit signals from the distal interface pod, and to output a feedback control signal in response to user command sense circuit signals; and

a signal generator in communication with the user inputs and the feedback circuit, and configured to accept the user command and feedback control signals, and to output a control signal in response to the user command and feedback control signals, wherein the control signal is a low power representation of the desired output of the power generator.

56. A high frequency electrosurgical generator as defined in claim 55, wherein the at least one sense circuit signal comprises a signal sensing the electrical current delivered by the electrosurgical tool to the patient.

57. A high frequency electrosurgical generator as defined in claim 55, wherein the at least one sense circuit signal comprises a signal sensing the voltage delivered by the electrosurgical tool to the patient.

58. A high frequency electrosurgical generator as defined in claim 55, wherein the signal generator further comprises:

an oscillator configured to output a periodic waveform;

a low pass filter connected to the output of the oscillator, configured to receive the periodic waveform and to output an essentially sinusoidal waveform at the same frequency as the periodic waveform;

a voltage controlled amplifier connected to the output of the low pass filter and in communication with the feedback circuit, configured to receive the sinusoidal waveform and output an amplified sinusoidal waveform, wherein the sinusoidal waveform amplitude is varied in response to the feedback control signal;

a filter connected to the output of the voltage controlled amplifier, configured to receive the amplified sinusoidal waveform and output a filtered amplified waveform wherein harmonics are attenuated;

a safety switch connected to the output of the filter and in communication with the user controls, configured to pass or block the filtered amplified waveform in response to an output received from user controls; and

a buffer connector to the output of the safety switch, configured to accept the filtered amplified waveform passed by the safety switch and to output a control signal.

59. A high frequency electrosurgical generator as defined in claim 58, wherein the periodic waveform is sinusoidal.

60. A high frequency electrosurgical generator as defined in claim 58, wherein the periodic waveform is a square wave.

61. A high frequency electrosurgical generator as defined in claim 51, further comprising a remote switch in communication with the control unit, configured to turn the output of the power generator on and off.

62. A high frequency electrosurgical generator as defined in claim 51, wherein the control signal is a sinusoidal waveform having a frequency between about 1 MHz and about 14 MHz .

63. A high frequency electrosurgical generator as defined in claim 51, wherein the control signal is a sinusoidal waveform having a frequency of about 3 MHz to about 6 MHz.

64. A high frequency electrosurgical generator as defined in claim 51, wherein the control signal is a sinusoidal waveform having a frequency of about 3.4 MHz to about 5 MHz.

65. A high frequency electrosurgical generator as defined in claim 51, wherein the electrical power generated for use with an electrosurgical tool is a sinusoidal waveform having a frequency between about 1 MHz and about 14 MHz.

66. A high frequency electrosurgical generator as defined in claim 51, wherein the electrical power generated for use with an electrosurgical tool is a sinusoidal waveform having a frequency of about 3 MHz to about 8 MHz.

67. A high frequency electrosurgical generator as defined in claim 51, wherein the electrical power generated for use with an electrosurgical tool is a sinusoidal waveform having a frequency of about 3.4 MHz to about 5 MHz.

68. A high frequency electrosurgical generator as defined in claim 51, wherein the electrical power generated for use with an electrosurgical tool may be up to 1,000 watts.

69. A high frequency electrosurgical generator as defined in claim 51, wherein the electrical power generated for use with an electrosurgical tool may be up to 700 volts rms.

70. A high frequency electrosurgical generator as defined in claim 51, wherein the electrical power generated for use with an electrosurgical tool may be up to 5 amps of current.

71. A high frequency electrosurgical generator as defined in claim 51, wherein generated electrical power is gated on and off at a desired frequency to produce a gated power signal.

72. A high frequency electrosurgical generator as defined in claim 71, wherein the duty factor of the generated electrical power is selected to have a desired ratio between the on and off periods of the gated power signal.

73. A high frequency electrosurgical generator as defined in claim 72, wherein the duty factor is between about 2% to 100%.

74. A high frequency electrosurgical generator as defined in claim 72, wherein the duty factor is between 20% to 40%.

75. A high frequency electrosurgical generator as defined in claim 72, wherein the duty factor is between 50% to 100%.

76. A high frequency electrosurgical generator as defined in claim 71, wherein when the generated electrical power is gated on the electrical power follows a ramped rectangular envelope.

77. A high frequency electrosurgical generator as defined in claim 71, wherein when the generated electrical power is gated on the electrical power follows a trapezoidal rectangular envelope.

78. A high frequency electrosurgical generator as defined in claim 71, wherein when the generated electrical power is gated on the electrical power follows a zero crossing, switched, rectangular envelope.