Narrow gauge high strength choked wet tip microwave ablation antenna
View Patent ↗An electromagnetic surgical ablation probe having a coaxial feedline and cooling chamber is disclosed. The disclosed probe includes a dipole antenna arrangement having a radiating section, a distal tip coupled to a distal end of the radiating section, and a ring-like balun short, or choke, which may control a radiation pattern of the probe. A conductive tube disposed coaxially around the balun short includes at least one fluid conduit which provides coolant, such as dionized water, to a cooling chamber defined within the probe. A radiofrequency transparent catheter forms an outer surface of the probe and may include a lubricious coating.
1. An ablation probe, comprising:
a tubular shaft;
a coaxial feedline disposed within the tubular shaft, the coaxial feedline including an outer conductor;
a balun short disposed in electrical communication around the outer conductor, the balun short including at least one longitudinal notch defined therein;
a conductive tube disposed coaxially around the balun short and within the tubular shaft, the conductive tube defining at least one fluid conduit; and
an inflow tube disposed longitudinally along the outer conductor and at least partially within the at least one longitudinal notch.
2. The ablation probe according to claim 1 , wherein the balun short includes a plurality of additional longitudinal notches defined therein adapted to receive a corresponding rib member therein.
3. The ablation probe according to claim 2 , wherein the rib members divide the at least one fluid conduit into at least two longitudinal channels.
4. The ablation probe according to claim 1 , wherein a distal end of the conductive tube is positioned about one quarter wavelength distally from the balun short.
5. The ablation probe according to claim 1 , wherein the balun short is formed from a conductive material selected from the group consisting of a screen material, a mesh material, and a woven material.
6. The ablation probe according to claim 1 , wherein the balun short is formed from a conductive material selected from the group consisting of a metallic material and a polymeric material.
7. The ablation probe according to claim 1 , wherein the coaxial feedline further includes an inner conductor and the outer conductor is disposed coaxially about the inner conductor.
8. The ablation probe according to claim 7 , wherein the coaxial feedline further includes a dielectric disposed between the inner conductor and the outer conductor and the inner conductor and the dielectric extend beyond a distal end of the outer conductor.
9. The ablation probe according to claim 8 , further comprising a radiating section having a proximal end operably coupled to a distal end of the inner conductor.
10. The ablation probe according to claim 1 , further comprising a distal tip coupled to a distal end of the tubular shaft.
11. An ablation system, comprising:
a source of microwave ablation energy; and
an ablation probe including:
a tubular shaft;
a coaxial feedline disposed within the tubular shaft, the coaxial feedline coupled to the source of microwave ablation energy and including an outer conductor;
a balun short disposed in electrical communication around the outer conductor, the balun short including at least one longitudinal notch defined therein;
a conductive tube disposed coaxially around the balun short and within the tubular shaft, the conductive tube defining at least one fluid conduit; and
an inflow tube disposed longitudinally along the outer conductor and at least partially within the at least one longitudinal notch.
12. The ablation system according to claim 11 , further comprising a source of coolant in fluid communication with the at least one fluid conduit.
13. The ablation system according to claim 11 , wherein the balun short includes a plurality of additional longitudinal notches defined therein adapted to receive a corresponding rib member therein.
14. The ablation system according to claim 13 , wherein the rib members divide the at least one fluid conduit into at least two longitudinal channels.
15. The ablation system according to claim 11 , wherein a distal end of the conductive tube is positioned about one quarter wavelength distally from the balun short.
16. The ablation system according to claim 11 , wherein the balun short is formed from a conductive material selected from the group consisting of a screen material, a mesh material, and a woven material.
17. The ablation system according to claim 11 , wherein the balun short is formed from a conductive material selected from the group consisting of a metallic material and a polymeric material.
18. The ablation system according to claim 11 , wherein the coaxial feedline further includes an inner conductor and the outer conductor is disposed coaxially about the inner conductor.
19. The ablation system according to claim 18 , wherein the coaxial feedline further includes a dielectric disposed between the inner conductor and the outer conductor and the inner conductor and the dielectric extend beyond a distal end of the outer conductor.
20. The ablation system according to claim 19 , further comprising a radiating section having a proximal end operably coupled to a distal end of the inner conductor.