RF ablation systems and methods including a cannula with contacts or a connector
An RF ablation cannula includes a cannula shaft; an active tip as part of, or coupled to, the cannula shaft; a cannula hub coupled to the cannula shaft, the cannula hub including at least a first cannula contact and a second cannula contact, wherein the first cannula contact is electrically coupled to the active tip; and a wire extending along the cannula shaft and attached to the active tip or cannula shaft to form a thermocouple, wherein the wire is electrically coupled to the second cannula contact. As an addition to, or an alternative to, the cannula contacts, the cannula hub can include a connector with connector pins or contacts coupled to the active tip and wire.
1 . An RF ablation system, comprising:
an RF ablation cannula comprising:
a cannula shaft;
an active tip as part of, or coupled to, the cannula shaft;
a cannula hub coupled to the cannula shaft, the cannula hub comprising at least a first cannula contact and a second cannula contact, wherein each of the first cannula contact and the second cannula contact comprises a ring contact having an outer diameter defining an outer cylindrical contact surface configured for electrically coupling to an external contact, wherein the first cannula contact is electrically coupled to the active tip; and
a wire extending along the cannula shaft and attached to the active tip or cannula shaft to form a thermocouple, wherein the wire is electrically coupled to the second cannula contact; and
a coupler comprising:
a first coupler contact and a second coupler contact configured for attaching and electrically coupling to the first cannula contact and second cannula contact of the RF ablation cannula, respectively, wherein the first coupler contact and the second coupler contact each have a partial ring shape complementary to the outer cylindrical contact surfaces of the first cannula contact and second cannula contact, respectively,
a cable electrically coupled to the first and second coupler contacts and terminating in a connector configured to couple to an RF generator, and
a coupler clip with the first and second coupler contacts directly attached to and extending from the coupler clip, wherein the coupler clip is configured and arranged to facilitate attachment of the coupler to the cannula hub of the RF ablation cannula, wherein the coupler clip comprises a first wing from which the first and second coupler contacts extend and to which the first and second coupler contacts are directly attached, a second wing, and an arm attached to, and between, the first and second wings.
2 . The RF ablation system of claim 1 , wherein the cannula hub comprises a cylindrical spacer disposed between the first and second cannula contacts.
3 . The RF ablation system of claim 2 , wherein an outer diameter of the cylindrical spacer is greater than the outer diameters of the first and second cannula contacts.
4 . The RF ablation system of claim 1 , wherein the first cannula contact differs from the second cannula contact in size or shape.
5 . The RF ablation system of claim 1 , wherein the cannula shaft is hollow and either the cannula shaft or active tip has an opening.
6 . The RF ablation system of claim 5 , wherein the cannula hub defines a port for injection of fluid into the cannula hub, through the hollow cannula shaft, and out the opening.
7 . The RF ablation system of claim 5 , further comprising an injection tube extending from the cannula hub, wherein the injection tube defines a port for injection of fluid into the injection tube, through the cannula hub, through the hollow cannula shaft, and out the opening.
8 . The RF ablation system of claim 1 , wherein the active tip is sharp.
9 . The RF ablation system of claim 1 , wherein the cannula shaft is conductive, the cannula further comprising insulation extending along the cannula shaft from the cannula hub to the active tip.
10 . The RF ablation system of claim 9 , wherein the wire is disposed over, or embedded within, the insulation.
11 . The RF ablation system of claim 1 , wherein the arm is biased to bring the first and second wings toward each other.
12 . The RF ablation system of claim 1 , wherein the first and second coupler contacts are configured to circumferentially engage a portion of the outer cylindrical contact surface of the first or second cannula contacts, respectively.
13 . The RF ablation system of claim 12 , wherein the first and second coupler contacts have an inner diameter equal to an outer diameter of the first and second cannula contacts.
14 . The RF ablation system of claim 1 , further comprising the RF generator configured to electrically couple to the coupler.
15 . The RF ablation system of claim 1 , wherein the first and second cannula contacts are disposed circumferentially relative to a longitudinal axis defined by at least a proximal portion of the cannula shaft.
16 . The RF ablation system of claim 1 , wherein the first and second cannula contacts are disposed circumferentially around the cannula shaft.
17 . The RF ablation system of claim 1 , wherein the ring contact of each of the first and second cannula contacts defines an inner diameter.
18 . The RF ablation system of claim 1 , wherein the second wing comprises a bar with an insulative material disposed around the bar for gripping by a user.
19 . The RF ablation system of claim 18 , wherein the cannula hub comprises a cylindrical spacer disposed between the first and second cannula contacts and the bar comprises prongs that are configured to flank the cylindrical spacer.
20 . The RF ablation system of claim 1 , wherein the first wing comprises first and second shanks extending to the first and second coupler contacts, respectively, and an insulative material disposed over at least a portion of each of the first and second shanks for gripping by a user.