Microwave thermometry for microwave ablation systems

• US 9,151,680 B2
• Filed: 06/21/2013
• Issued: 10/06/2015
• Est. Priority Date: 06/22/2012
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Covidien LP (Medtronic Plc)
• Inventors: Brannan, Joseph D.
• Primary Examiner(s): Stoklosa, Joseph
• Assistant Examiner(s): Ram, Jocelyn D
• Application Number:
  US13/924,315
• Publication Number:
  US 20130345693A1
• Time in Patent Office: 837 Days
• Field of Search: 606/34, 606/38, 606/42
• US Class Current: 1/1
• CPC Class Codes: A61B 18/1815 using microwaves
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00642 with feedback, i.e. closed loop control
• CPC Class Codes: A61B 2018/00666 using a threshold value
• CPC Class Codes: A61B 2018/00702 Power or energy
• CPC Class Codes: A61B 2018/00791 Temperature
• CPC Class Codes: A61B 2018/00821 measured by a thermocouple
• CPC Class Codes: A61B 2018/00988 Means for storing information, e.g. calibration constants, or for preventing excessive use, e.g. usage, service life counter
• CPC Class Codes: A61B 2018/1823 Generators therefor
• CPC Class Codes: A61B 2018/183 characterised by the type of antenna
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: A61B 5/0507 using microwaves or terahertz waves
• CPC Class Codes: G01J 5/0837 Microantennas, e.g. bow-tie
• CPC Class Codes: G01K 11/006 using measurement of the effect of a material on microwaves or longer electromagnetic waves, e.g. measuring temperature via microwaves emitted by the object G01K17/003, G01J5/00 take precedence; measuring the effect of a material on X-, gamma- or particle radiation G01K11/30
• CPC Class Codes: G01K 13/00 Thermometers specially adapted for specific purposes
• CPC Class Codes: G01K 7/02 using thermoelectric elements, e.g. thermocouples
• CPC Class Codes: H01R 13/66 Structural association with built-in electrical component coupling devices having concentrically or coaxially-arranged contacts H01R24/38

Abstract

A microwave ablation system incorporates a microwave thermometer that couples to a microwave transmission network connecting a microwave generator to a microwave applicator to measure noise temperature. The noise temperature is processed to separate out components of the noise temperature including the noise temperature of the tissue being treated and the noise temperature of the microwave transmission network. The noise temperature may be measured by a radiometer while the microwave generator is generating the microwave signal or during a period when the microwave signal is turned off. The microwave ablation system may be configured as a modular system having one or more thermometry network modules that are connectable between a microwave applicator and a microwave generator. Alternatively, the modular system includes a microwave generator, a microwave applicator, and a microwave cable that incorporate a microwave thermometry network module.

Claims

1. A microwave thermometry network module comprising:

a housing;

a first connector assembly coupled to a first end of the housing and a second connector assembly coupled to a second end of the housing;

a microwave transmission line coupled between the first connector assembly and the second connector assembly;

a measurement module coupled to the microwave transmission line, the measurement module including a coupling network, a radiometer, and a data bus connector disposed within the housing, the coupling network being configured to couple a portion of the signals propagating through the microwave transmission line to the radiometer, the radiometer being configured to process the portion of the signals to obtain a noise temperature signal, and the data bus connector being configured to transmit the noise temperature signal to at least one component of a microwave ablation system connected to the first connector assembly or second connector assembly.

2. The microwave thermometry network module according to claim 1, further comprising a controller coupled to the radiometer and configured to determine a temperature value based on the noise temperature signal.

3. The microwave thermometry network module according to claim 2, further comprising a data bus coupled between the first and second connector assemblies,

wherein the controller is coupled to the data bus and configured to transmit the temperature value to at least one component of the microwave ablation system connected to the first or second connector assembly.

4. The microwave thermometry network module according to claim 2, further comprising:

a display disposed on the housing; and

a display driver coupled to the display,

wherein the controller controls the display driver to display the temperature value.

5. The microwave thermometry network module according to claim 2, further comprising a temperature selector for selecting a temperature at which the microwave signal is to be shut off,

wherein the controller transmits a shut off message to a microwave generator coupled to the microwave thermometry network module if the temperature value is greater than the selected temperature.

6. The microwave thermometry network module according to claim 2, wherein the temperature value represents a temperature of tissue being treated or a temperature of a portion of a microwave ablation system component.

7. The microwave thermometry network module according to claim 1, further comprising a power supply line coupled between the first and second connector assemblies and configured to carry a power signal between the first and second connector assemblies.