Ablation systems, probes, and methods for reducing radiation from an ablation probe into the environment

Abstract

The ablation systems, ablation probes, and corresponding methods according to the present disclosure reduce or eliminate energy radiating from an ablation probe into the environment. Some ablation probes include a retractable sheath that shields at least the radiating portion of the ablation probe. The retractable sheath and/or the ablation probe may include conduits through which a fluid may flow to shield the radiating portion and to drive the retractable sheath to an extended state. Other ablation probes include apertures defined in the probe walls through which the fluid can flow to expand a balloon surrounding the radiating portion. Yet other ablation probes include a thermal indicator to indicate the temperature of the ablation probe to a user. The ablation systems include fluid circuits and associated mechanical controls for varying the contents and/or flow rate of the fluid provided to the radiating portion of the ablation probe.

1 - 17 . (canceled) 
     
     
         18 . A fluid circuit for an ablation probe, the fluid circuit comprising:
 a first fluid supply conduit configured to transfer a first fluid from a source of first fluid to a radiating portion of an ablation probe;   a second fluid supply conduit configured to transfer a second fluid from a source of second fluid to the radiating portion of the ablation probe; and   a manual control operatively coupled to the first fluid supply conduit and the second fluid supply conduit, the manual control configured to control a supply of the first fluid and the second fluid to the radiating portion of the ablation probe.   
     
     
         19 . The fluid circuit according to  claim 18 , further comprising a fluid return conduit configured to carry the first fluid, a mixture of the first fluid and the second fluid, or the second fluid away from the radiating portion. 
     
     
         20 . The fluid circuit according to  claim 18 , wherein the second fluid is a liquid solution containing particles that absorb electromagnetic energy. 
     
     
         21 . The fluid circuit according to  claim 18 , wherein the second fluid is selected from the group consisting of air and gas containing nitrogen. 
     
     
         22 . The fluid circuit according to  claim 18 , further comprising a common fluid conduit configured to receive the first fluid from the first fluid supply conduit and the second fluid from the second fluid supply conduit, the common fluid conduit configured to supply the first fluid and the second fluid to the radiating portion of the ablation probe. 
     
     
         23 . The fluid circuit according to  claim 18 , wherein the first fluid supply conduit includes a first recessed portion and the second fluid supply conduit includes a second recessed portion, and
 wherein the fluid circuit further comprises:   a fluid pump configured to fit within the second recessed portion and to move from a first position to a second position, the fluid pump configured to pump the second fluid through the second fluid supply conduit when the fluid pump is at the second position; and   an impeller operatively coupled to the fluid pump and configured to drive the fluid pump, the impeller configured to fit within the first recessed portion and to move from a third position to a fourth position, the impeller configured to be driven by the first fluid flowing through the first fluid supply conduit when the impeller is at the fourth position,   wherein the manual control is operatively coupled to the impeller and the fluid pump and is configured to move the impeller and the fluid pump between (a) respective first and third positions and (b) respective second and fourth positions.   
     
     
         24 . The fluid circuit according to  claim 23 , further comprising:
 a fluid return conduit;   a bypass fluid conduit coupled between the first fluid supply conduit and the fluid return conduit;   a fluid pump disposed within the second fluid supply conduit, the fluid pump configured to pump the second fluid through the second fluid supply conduit;   an impeller operatively coupled to the fluid pump and configured to drive the fluid pump, the impeller disposed within the bypass fluid conduit, the impeller configured to be driven by the first fluid flowing through the bypass fluid conduit; and   a bypass valve assembly coupled to the first fluid supply conduit and the bypass fluid conduit, the bypass valve assembly configured to divert the first fluid flowing in the first fluid supply conduit to the bypass fluid conduit when the bypass valve assembly is actuated.   
     
     
         25 . The fluid circuit according to  claim 24 , wherein the second fluid is a liquid solution containing particles that absorb electromagnetic energy. 
     
     
         26 . The fluid circuit according to  claim 24 , wherein the second fluid is selected from the group consisting of air and a gas containing nitrogen. 
     
     
         27 . The fluid circuit according to  claim 24 , further comprising a check valve disposed within the second fluid supply conduit, the check valve configured to prevent the first fluid from flowing into the second fluid supply conduit. 
     
     
         28 . The fluid circuit according to  claim 24 , further comprising a check valve disposed within the fluid return conduit, the check valve configured to prevent fluid from flowing distally. 
     
     
         29 . A fluid circuit comprising:
 a first fluid supply conduit that supplies a first fluid to a radiating portion of an ablation probe when the radiating portion is inserted in tissue; and   a second fluid supply conduit that supplies a second fluid to the radiating portion of the ablation probe when the radiating portion is removed from tissue to shield the radiating portion from a surrounding environment.   
     
     
         30 . The fluid circuit according to  claim 29 , further comprising a fluid return conduit configured to carry the first fluid, a mixture of the first fluid and the second fluid, or the second fluid away from the radiating portion. 
     
     
         31 . The fluid circuit according to  claim 29 , further comprising a manual control operatively coupled to the first fluid supply conduit and the second fluid supply conduit, the manual control configured to control a supply of the first fluid and the second fluid to the radiating portion of the ablation probe. 
     
     
         32 . The fluid circuit according to  claim 31 , wherein the first fluid supply conduit includes a first recessed portion and the second fluid supply conduit includes a second recessed portion,
 wherein the fluid circuit further comprises:
 a fluid pump configured to fit within the second recessed portion and to move from a first position to a second position, the fluid pump configured to pump the second fluid through the second fluid supply conduit when the fluid pump is moved to the second position; and 
 an impeller operatively coupled to the fluid pump and configured to drive the fluid pump, the impeller configured to fit within the first recessed portion and to move from a third position to a fourth position, the impeller configured to be driven by the first fluid flowing through the first fluid supply conduit when the impeller is moved to the fourth position, and 
   wherein the manual control is operatively coupled to the impeller and the fluid pump and is configured to move the impeller and the fluid pump between (a) respective first and third positions and (b) respective second and fourth positions.   
     
     
         33 . The fluid circuit according to  claim 32 , further comprising:
 a fluid return conduit;   a bypass fluid conduit fluidly coupled between the first fluid supply conduit and the fluid return conduit;   a fluid pump disposed within the second fluid supply conduit, the fluid pump configured to pump the second fluid through the second fluid supply conduit;   an impeller operatively coupled to the fluid pump and configured to drive the fluid pump, the impeller disposed within the bypass fluid conduit, the impeller configured to be driven by the first fluid flowing through the bypass fluid conduit; and   a bypass valve assembly fluidly coupled to the first fluid supply conduit and the bypass fluid conduit, the bypass valve assembly configured to divert the first fluid flowing in the first fluid supply conduit to the bypass fluid conduit when actuated.   
     
     
         34 . The fluid circuit according to  claim 33 , further comprising a check valve disposed within the second fluid supply conduit, the check valve configured to prevent the first fluid from flowing into the second fluid supply conduit. 
     
     
         35 . The fluid circuit according to  claim 33 , further comprising a check valve disposed within the fluid return conduit, the check valve configured to prevent fluid from flowing distally. 
     
     
         36 . The fluid circuit according to  claim 29 , wherein the first fluid facilitates transmission of energy from the radiating portion. 
     
     
         37 . The fluid circuit according to  claim 29 , wherein the second fluid prevents transmission of energy from the radiating portion.