Electrosurgical generator apparatus

• US 7,846,156 B2
• Filed: 04/05/2006
• Issued: 12/07/2010
• Est. Priority Date: 10/24/2002
• Status: Active Grant

• Current Assignee: Stryker Corporation
• Original Assignee: Synergetics USA Incorporated (Bausch Health Cos., Inc.)
• Inventors: Malis, Leonard L., Malis, Jerry L., Solt, David L., Acorcey, Robert R., Groch, Anthony John
• Primary Examiner(s): PEFFLEY, MICHAEL F
• Application Number:
  US11/278,690
• Publication Number:
  US 20060184164A1
• Time in Patent Office: 1,707 Days
• Field of Search: 606 32- 41
• US Class Current: 606/34
• CPC Class Codes: A61B 18/1206 Generators therefor
• CPC Class Codes: A61B 2018/00636 Sensing and controlling the application of energy
• CPC Class Codes: A61B 2018/0075 Phase
• CPC Class Codes: A61B 2018/00755 Resistance or impedance
• CPC Class Codes: A61B 2018/00875 Resistance or impedance
• CPC Class Codes: A61B 5/053 Measuring electrical impedance or conductance of a portion of the body

Abstract

An electrosurgical generator apparatus controls a variable output signal to electrodes. The generator apparatus operates in a cut mode, a coagulation mode or a stimulate mode. The generator apparatus comprises a DC power supply that provides regulated low voltage and high voltage outputs and a radio frequency (RF) waveform generator circuit that provides pulse duration modulation (PDM) of a carrier signal. The carrier signal directly affects the variable output signal to the electrodes. A control circuit controls a variable output signal to electrodes used in electrosurgical procedures. The control circuit comprises a DC power supply circuit that provides regulated low voltage and high voltage outputs and an RF waveform generator circuit that provides pulse duration modulation of a carrier signal. The carrier signal directly affects the variable output signal to the electrodes.

Claims

1. An electrosurgical generator apparatus that controls a variable output signal to electrodes, the generator apparatus comprising:

(a) a DC power supply that provides regulated low voltage and high voltage outputs;

(b) a radio frequency (RF) waveform generator circuit that provides modulation of a carrier signal, the carrier signal directly affecting the variable output signal to the electrodes;

(c) an impedance monitoring circuit that detects an impedance as measured across a pair of leads of the electrodes, the impedance monitoring circuit including a bridge detector for measuring an overall signal and a reference detector for measuring a reference signal, the impedance being a complex value.

2. The electrosurgical generator apparatus according to claim 1, wherein the bridge detector further comprises a bridge in-phase detector for measuring overall in-phase components of the overall signal and a bridge quadrature detector for measuring overall quadrature components of the overall signal.

3. The electrosurgical generator apparatus according to claim 1, wherein the reference detector further comprises a reference in-phase detector for measuring reference in-phase components of the reference signal and a reference quadrature detector for measuring reference quadrature components of the reference signal.

4. The electrosurgical generator apparatus according to claim 1, wherein the impedance is correspondingly proportional to an amount of cell destruction caused by the generator apparatus.

5. The electrosurgical generator apparatus according to claim 1, wherein the complex impedance value includes magnitude and phase angle.