Method for calculating impedance and apparatus utilizing same
First Claim
1. A method for calculating impedance in a first circuit coupling a first radio frequency electrode to a radio frequency controller where the first radio frequency electrode is disposed in tissue of a mammalian body in the vicinity of a second radio frequency electrode coupled to a second circuit distinct from the first circuit comprising the steps of measuring the impedance of the first circuit to determine an impedance value IMP when radio frequency energy is being supplied to the first and second radio frequency electrodes, measuring the impedance of the first circuit to determine an impedance value IMP0 when radio frequency energy is being supplied to the first radio frequency electrode but not to the second radio frequency electrode, subtracting the impedance value IMP0 from the impedance value IMP to determine an impedance delta value IMP, remeasuring the impedance of the first circuit to determine an impedance value IMP2 when radio frequency energy is being supplied to the first and second radio frequency electrodes and subtracting the impedance delta value IMP from the impedance value IMP2 to arrive at a calculated impedance value for the first circuit.
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Accused Products
Abstract
A method for calculating the impedance in a first circuit coupling a first radio frequency electrode to a radio frequency controller where the first electrode is disposed in tissue in the vicinity of a second radio frequency electrode coupled to a second circuit. The impedance IMP of the first circuit is measured when energy is being supplied to both electrodes. The impedance IMP0 of the first circuit is also measured when energy is being supplied to the first electrode but not to the second electrode, and subtracted from the impedance value IMP to determine a delta value IMP. The impedance IMP2 of the first circuit is then measured when energy is being supplied to both electrodes. The impedance delta value IMP is subtracted from the impedance value IMP2 to arrive at a calculated impedance value for the first circuit. A computer-readable memory and apparatus utilizing the method are provided.
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Citations
16 Claims
- 1. A method for calculating impedance in a first circuit coupling a first radio frequency electrode to a radio frequency controller where the first radio frequency electrode is disposed in tissue of a mammalian body in the vicinity of a second radio frequency electrode coupled to a second circuit distinct from the first circuit comprising the steps of measuring the impedance of the first circuit to determine an impedance value IMP when radio frequency energy is being supplied to the first and second radio frequency electrodes, measuring the impedance of the first circuit to determine an impedance value IMP0 when radio frequency energy is being supplied to the first radio frequency electrode but not to the second radio frequency electrode, subtracting the impedance value IMP0 from the impedance value IMP to determine an impedance delta value IMP, remeasuring the impedance of the first circuit to determine an impedance value IMP2 when radio frequency energy is being supplied to the first and second radio frequency electrodes and subtracting the impedance delta value IMP from the impedance value IMP2 to arrive at a calculated impedance value for the first circuit.
- 13. A computer-readable memory for use with a radio frequency controller and a first circuit to couple a first radio frequency electrode to the controller and a second radio frequency electrode coupled to a second circuit distinct from the first circuit, the memory containing a computer program for causing the controller to calculate an impedance in the first circuit when the first radio frequency electrode is disposed in tissue of a mammalian body in the vicinity of the second radio frequency electrode by measuring the impedance of the first circuit to determine an impedance value IMP when radio frequency energy is being supplied to the first and second radio frequency electrodes, measuring the impedance of the first circuit to determine an impedance value IMP0 when radio frequency energy is being supplied to the first radio frequency electrode but not to the second radio frequency electrode, subtracting the impedance value IMP0 from the impedance value IMP to determine an impedance delta value IMP, remeasuring the impedance of the first circuit to determine an impedance value IMP2 when radio frequency energy is being supplied to the first and second radio frequency electrodes and subtracting the impedance delta value IMP from the impedance value IMP2 to arrive at a calculated impedance value for the first circuit.
- 15. A radio frequency controller for use with a first circuit to couple a first radio frequency electrode to the controller and with a second radio frequency electrode coupled to a second circuit distinct from the first circuit comprising a computer-readable memory containing a computer program for causing the controller to calculate an impedance in the first circuit when the first radio frequency electrode is disposed in tissue of a mammalian body in the vicinity of the second radio frequency electrode by measuring the impedance of the first circuit to determine an impedance value IMP when radio frequency energy is supplied to the first and second radio frequency electrodes, measuring the impedance of the first circuit to determine an impedance value IMP0 when radio frequency energy is being supplied to the first radio frequency electrode but not to the second radio frequency electrode, subtracting the impedance value IMP0 from the impedance value IMP to determine an impedance delta value IMP, remeasuring the impedance of the first circuit to determine an impedance value IMP2 when radio frequency energy is being supplied to the first and second radio frequency electrodes and subtracting the impedance delta value IMP from the impedance value IMP2 to arrive at a calculated impedance value for the first circuit, and a central processing unit coupled to the memory for executing the program in the memory.
Specification