System and method for treating tissue using an expandable antenna

1. An electrosurgical system for treating tissue, the system comprising:

an electrosurgical generator; and

a microwave ablation device configured to operably couple to the electrosurgical generator, the microwave ablation device including:

a radiating portion defining a longitudinal axis and configured to deliver energy from the electrosurgical generator to tissue, the radiating portion having an outer conductor and an inner conductor disposed within the outer conductor and separated by a dielectric material disposed on the inner conductor;

wherein one of the inner conductor or the outer conductor is movable relative to the other to cause at least a portion of the outer conductor to expand radially relative to the longitudinal axis.

2. The electrosurgical system according to claim 1 , wherein the microwave ablation device includes a distal tip coupled to at least one of the outer conductor or the inner conductor and proximal movement of the distal tip causes at least a portion of the outer conductor to expand radially relative to the longitudinal axis.

3. The electrosurgical system according to claim 1 , wherein the outer conductor is configured to separate into a plurality of deployable conductors in response to proximal movement of one of the inner conductor or the outer conductor relative to the other.

4. The electrosurgical system according to claim 3 , wherein each deployable conductor of the plurality of deployable conductors is configured to mechanically cut through tissue.

5. The electrosurgical system according to claim 3 , wherein each deployable conductor of the plurality of deployable conductors is configured to cut through tissue upon delivery of electrosurgical energy to the plurality of deployable conductors.

6. The electrosurgical system according to claim 3 , wherein a distance between the plurality of deployable conductors and the inner conductor defines an ablation region when the plurality of deployable conductors is radially expanded relative to the longitudinal axis.

7. The electrosurgical system according to claim 6 , wherein the outer conductor and the inner conductor are configured to form an electromagnetic field within the ablation region.

8. The electrosurgical system according to claim 1 , wherein the microwave ablation device includes a distal tip operably coupled to the inner conductor such that movement of the inner conductor along the longitudinal axis translates relative movement of the distal tip.

9. The electrosurgical system according to claim 1 , wherein at least a portion of the outer conductor is flexible.

10. The electrosurgical system according to claim 1 , wherein distal movement of the outer conductor relative to the inner conductor causes at least a portion of the outer conductor to expand radially relative to the longitudinal axis.

11. The electrosurgical system according to claim 1 , wherein proximal movement of the inner conductor relative to the outer conductor causes at least a portion of the outer conductor to expand radially relative to the longitudinal axis.

12. The electrosurgical system according to claim 1 , wherein the microwave ablation device includes a housing having an actuation element, the actuation element operably coupled to at least one of the inner conductor or the outer conductor and configured to move one of the inner conductor or the outer conductor relative to the other.

13. The electrosurgical system according to claim 1 , further comprising a sealant disposed around at least a distal portion of the outer conductor, wherein radial expansion of the outer conductor causes corresponding radial expansion of the sealant.