CPC A61B 18/1815 (2013.01) [A61B 2018/00083 (2013.01); A61B 2018/00577 (2013.01); A61B 2018/00982 (2013.01); A61B 2018/1823 (2013.01); A61B 2018/1853 (2013.01); A61B 2018/1861 (2013.01); A61B 2018/1892 (2013.01)] | 19 Claims |
1. An electrosurgical instrument comprising:
a coaxial feed cable for conveying microwave energy, the coaxial feed cable having an inner conductor, an outer conductor, and a dielectric material separating the inner conductor and the outer conductor; and
a radiating tip disposed at a distal end of the coaxial feed cable to receive the microwave energy, the radiating tip comprising:
an elongate conductor electrically connected to the inner conductor and extending in a longitudinal direction to form a microwave radiator;
a proximal tuning element electrically connected to the elongate conductor in a proximal region of the radiating tip;
a distal tuning element electrically connected to the elongate conductor in a distal region of the radiating tip; and
a dielectric body disposed around the elongate conductor, the proximal tuning element and the distal tuning element;
a conductive field shaping element disposed at a distal end of the coaxial feed cable, the conductive field shaping element being electrically connected to the outer conductor along a full length of the conductive field shaping element to increase an effective thickness of the outer conductor;
wherein the proximal tuning element and the distal tuning element are spaced apart in the longitudinal direction, whereby a microwave field emitted by the microwave radiator is shaped around the dielectric body; and
wherein a length of the distal tuning element in the longitudinal direction is greater than a length of the proximal tuning element in longitudinal direction.
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