System and method for monitoring a microwave tissue ablation process
AssigneeGyrus Medical Limited
InventorsDavid Nicholas Williams, Tudor Thomas
Life of this patent
Estimating the term…
Abstract
A method and system for monitoring a microwave tissue ablation process, particularly the determination of an ablation size estimate during microwave ablation of such tissue. The method includes applying a correction value to the determined temperature value, so as to provide a corrected temperature value
Claims17
A method of monitoring a microwave tissue ablation process, the method comprising:
- providing a power source operable to provide a controlled microwave energy output;
- providing a microwave probe having a body and an antenna extending through the body and operable to deliver microwave energy from the power source out of the microwave probe;
- providing a thermocouple on the body of the microwave probe, the thermocouple being separated from the body by a layer of thermally insulating material, the thermocouple being operable to generate an output voltage in dependence upon a temperature experienced by the thermocouple;
- supplying a controlled microwave energy output from the power source to the antenna, thereby causing microwave energy to radiate from the antenna to form an ablation zone;
- detecting an output voltage generated by the thermocouple in response to a temperature experienced by the thermocouple;
- determining a temperature value relating to the detected output voltage;
- applying a correction value to the determined temperature value, so as to provide a corrected temperature value, the correction value relating to a total amount of energy supplied to the antenna from the start of such ablation to the determination of the temperature value.
A method of controlling a microwave probe during microwave ablation of tissue, the method comprising a method of monitoring tissue temperature as claimed in any one of the preceding claims, and further comprising controlling the microwave energy supplied from the power source to the antenna such that the corrected temperature value substantially reaches a predetermined target value.
A microwave ablation apparatus comprising:
- a power source operable to provide a controlled microwave energy output;
- a microwave probe having a body and an antenna extending through the body and operable to deliver microwave energy from the power source out of the microwave probe;
- a thermocouple on the body of the microwave probe, the thermocouple being separated from the body by a layer of thermally insulating material, the thermocouple being operable to generate an output voltage in dependence upon a temperature experienced by the thermocouple;
- a detector operable to detect an output voltage generated by the thermocouple in response to a temperature experienced by the thermocouple;
- a calculation unit operable to determine a temperature value relating to the detected output voltage;
- a correction unit operable to apply a correction value to such a determined temperature value, and to provide a corrected temperature value, the correction value relating to a total amount of energy supplied to the antenna from the start of such ablation to the determination of the temperature value;
- and
- a controller operable to control microwave energy supplied to the antenna from the power source such that the corrected temperature value reaches a predetermined target value.
An apparatus as claimed in claimed 10, wherein the predetermined correction value is chosen from a range of predetermined correction values in dependence upon power level and application time of the microwave energy.
Dependencies are inferred from the claim text.