Dual-band dipole microwave ablation antenna

Abstract

A triaxial microwave antenna assembly is disclosed. The triaxial microwave antenna includes a feedline having an inner conductor, a central conductor disposed about the inner conductor and an outer conductor disposed about the central conductor and a radiating portion including a high frequency radiating section and a low frequency radiating section.

1 - 15 . (canceled) 
     
     
         16 . A method for forming a lesion, comprising:
 supplying microwave energy at a first frequency to a first frequency radiating section of a triaxial microwave antenna assembly;   supplying microwave energy at a second frequency to a second frequency radiating section of the triaxial microwave antenna assembly; and   selectively energizing at least one of the first frequency radiating section or the second radiating section to adjust a property of the lesion.   
     
     
         17 . The method according to  claim 16 , wherein the property of the lesion is selected from the group consisting of shape, diameter and depth. 
     
     
         18 . The method according to  claim 16 , wherein the first frequency is higher than the second frequency. 
     
     
         19 . The method according to  claim 16 , wherein the triaxial microwave antenna assembly includes an inner conductor, a central conductor disposed about the inner conductor, and an outer conductor disposed about the central conductor. 
     
     
         20 . The method according to  claim 19 , wherein the first radiating section includes at least a portion of the inner conductor and at least a portion of the central conductor. 
     
     
         21 . The method according to  claim 20 , wherein the first frequency radiating section has a first predetermined length and the portion of the inner conductor extends a first predetermined distance from a distal end of the central conductor and the portion of the central conductor extends the first predetermined distance from a distal end of the outer conductor, such that the first predetermined length is equal to about twice the first predetermined distance. 
     
     
         22 . The method according to  claim 21 , wherein the first predetermined distance is a quarter wavelength of an amplitude of the microwave energy supplied at the first frequency. 
     
     
         23 . The method according to  claim 21 , wherein the second radiating section includes at least a portion of the central conductor and at least a portion of the outer conductor and the portion of the outer conductor is choked at a second predetermined distance. 
     
     
         24 . The method according to  claim 23 , wherein the second frequency radiating section has a second predetermined length, which is equal to about a sum of the first predetermined length and the second predetermined distance, the sum being equal to about a half wavelength of an amplitude of the microwave energy supplied at the second frequency. 
     
     
         25 . A method for forming a lesion, comprising:
 supplying microwave energy at a first frequency or a second frequency to a microwave antenna assembly having a first frequency radiating section and a second frequency radiating section having a choke; and   limiting the microwave energy being supplied at the second frequency to the second frequency radiating section via the choke.   
     
     
         26 . The method according to  claim 25 , selectively energizing at least one of the first frequency radiating section or the second radiating section to adjust a property of the lesion. 
     
     
         27 . The method according to  claim 26 , wherein the property of the lesion is selected from the group consisting of shape, diameter and depth. 
     
     
         28 . The method according to  claim 25 , wherein the first frequency is higher than the second frequency. 
     
     
         29 . The method according to  claim 25 , wherein the microwave antenna assembly is a triaxial antenna assembly and includes an inner conductor, a central conductor disposed about the inner conductor and an outer conductor disposed about the central conductor. 
     
     
         30 . The method according to  claim 29 , wherein the first radiating section includes at least a portion of the inner conductor and at least a portion of the central conductor. 
     
     
         31 . The method according to  claim 20 , wherein the first frequency radiating section has a first predetermined length and the portion of the inner conductor extends a first predetermined distance from a distal end of the central conductor and the portion of the central conductor extends from a distal end of the first predetermined distance from the outer conductor, such that the first predetermined length is equal to about twice the first predetermined distance. 
     
     
         32 . The method according to  claim 31 , wherein the first predetermined distance is a quarter wavelength of an amplitude of the microwave energy supplied at the first frequency. 
     
     
         33 . The method according to  claim 31 , wherein the second radiating section includes at least a portion of the central conductor and at least a portion of the outer conductor wherein the portion of the outer conductor is choked at a second predetermined distance. 
     
     
         34 . The method according to  claim 33 , wherein the second frequency radiating section has a second predetermined length, which is equal to about a sum of the first predetermined length and the second predetermined distance, the sum being equal to about a half wavelength of an amplitude of the microwave energy supplied at the second frequency.