RF ablation systems with bipolar RF electrodes and methods of making and using same

Abstract

An RF ablation system may include a bipolar RF electrode having two electrodes. Some bipolar RF electrodes may include a metal tube forming one of the electrodes. The metal tube may be notched to facilitate bending of the metal tube. Some bipolar RF electrodes may include a multi-lumen tube for a conductor. Some multi-lumen tubes may be made of a relatively high hardness material providing column strength for bipolar RF electrodes. Some RF ablation systems may include an adapter for an RF generator to connect each electrode to a different channel. Various arrangements of channels of the RF generator and conductors of the bipolar RF electrode may be used to couple the electrode and the temperature sensor to the RF generator.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application Serial No. 63 / 413,133, filed on October 4, 2022, which is incorporated herein by reference. Technical Field

[0003] The present disclosure is directed to the field of radiofrequency (RF) ablation systems and methods of making and using the same. The present disclosure is also directed to RF ablation systems and methods including bipolar RF electrodes, and methods of making and using the same. Background Art

[0004] Radiofrequency (RF) generators and electrodes can be used for pain relief or functional modification. Radiofrequency ablation (RFA) is a safe, proven method of interrupting pain signals such as those from irritated facet joints in the spine, the geniculate nerve in the knee joint, and the femoral and obturator nerves in the hip. Radiofrequency current is used to heat a small volume of nerve tissue, thereby interrupting pain signals from that specific area. RF ablation is designed to provide long-lasting pain relief.

[0005] For example, RF electrodes may be positioned near the target tissue and then used to heat the target tissue by dissipation of RF power output by the RF signal in the target tissue.Temperature monitoring of the target tissue by temperature sensors in the electrodes may be used to control the process. Summary of the invention

[0006] In one aspect, an RF ablation electrode includes an electrode shaft; a metal tube forming at least a portion of the electrode shaft and including a proximal portion and a distal portion, wherein at least the distal portion of the metal tube includes a plurality of cuts to facilitate bending of the distal portion, wherein at least a portion of the distal portion of the metal tube includes a first electrode; a spacer disposed away from the first electrode; a second electrode disposed away from the spacer; a connector; and at least two conductors electrically coupled to the connector, wherein different conductors of the at least two conductors are electrically coupled to the first electrode and the second electrode, respectively.

[0007] In at least some aspects, the plurality of cuts are arranged in an interrupted spiral pattern. In at least some aspects, the RF ablation electrode further comprises a non-conductive sheath disposed on at least the proximal portion of the metal tube but not on the first electrode. In at least some aspects, the plurality of conductors comprises a first conductor electrically attached to the proximal portion of the metal tube. In at least some aspects, the proximal portion of the metal tube does not comprise any cuts. In at least some aspects, the second electrode is a tip electrode. In at least some aspects, the spacer, the first electrode, or the second electrode comprises a radiopaque marker.

[0008] In another aspect, an RF ablation electrode includes an electrode shaft comprising a proximal portion, a distal portion, and a multi-lumen tube extending along at least a portion of the proximal portion of the electrode shaft, the multi-lumen tube defining a plurality of conductor lumens extending along the multi-lumen tube; a first electrode disposed along or coupled to the distal portion of the electrode shaft; a spacer disposed away from the first electrode; a second electrode disposed away from the spacer; a connector; and at least two conductors electrically coupled to the connector, wherein different conductors of the at least two conductors are electrically coupled to the first electrode and the second electrode, respectively, wherein at least a portion of at least one of the at least two conductors extends along at least one of the conductor lumens of the multi-lumen tube.

[0009] In at least some aspects, the multi-lumen tube has exactly three or four conductor lumens. In at least some aspects, the multi-lumen tube also includes a stylet lumen that is different in size from the conductor lumen. In at least some aspects, the multi-lumen tube is made of a material with a higher hardness than the material forming a portion of the electrode shaft adjacent to the first electrode. In at least some aspects, the second electrode is a tip electrode or a ring electrode.

[0010] A further aspect is an RF ablation system comprising any of the RF ablation electrodes described above and an RF generator coupled or coupleable to the RF ablation electrode.

[0011] In yet another aspect, an RF ablation system includes a bipolar RF electrode comprising an electrode shaft, a first electrode and a second electrode disposed along a distal portion of the electrode shaft, a connector, a first conductor electrically coupled to the first electrode and the connector, and a second conductor electrically coupled to the second electrode and the connector; and an adapter including an electrode connector configured to be connected to a connector of the bipolar RF electrode, a first port connector and a second port connector configured to be separately connected to different ports of an RF generator, a first adapter conductor configured to electrically couple the electrode connector to the first port connector, and a second adapter conductor configured to electrically couple the electrode connector to the second port connector, wherein, when the electrode connector of the adapter is coupled to the connector of the bipolar RF electrode, the first conductor of the bipolar RF electrode is electrically coupled to the first adapter conductor, and the second conductor of the bipolar RF electrode is electrically coupled to the second adapter conductor.

[0012] In at least some aspects, the RF ablation system also includes an RF generator including a first port configured to receive a first port connector of the adapter and a second port configured to receive a second port connector of the adapter.

[0013] In another aspect, an RF ablation system includes an RF generator comprising an RF source, a ground, a temperature measurement arrangement, and at least one port, wherein the RF generator defines at least three channels, wherein the RF source and the ground are electrically coupled to different channels of the at least three channels, and the temperature measurement arrangement is electrically coupled to two of the at least three channels; and a bipolar RF electrode comprising an electrode shaft, a first electrode and a second electrode disposed along a distal portion of the electrode shaft, a temperature sensor disposed along the distal portion of the electrode shaft, a connector, and at least three conductors extending along the electrode shaft and electrically coupled to the connector, wherein the first electrode and the second electrode are electrically coupled to different conductors of the at least three conductors, and the temperature sensor is coupled to two of the at least three conductors, wherein the connector of the bipolar RF electrode is configured to be electrically coupled to at least one of the at least one port of the RF generator such that, when coupled, the first electrode is electrically coupled to the RF source, the second electrode is electrically coupled to the ground, and the temperature sensor is electrically coupled to the temperature measurement arrangement.

[0014] In at least some aspects, the at least three channels include a first channel, a second channel, a third channel, and a fourth channel, and the at least three conductors include a first conductor coupled to the first electrode, a second conductor coupled to the second electrode, and third and fourth conductors coupled to the temperature sensor, wherein, when the connector of the bipolar RF electrode is electrically coupled to at least one port of the RF generator, the first conductor couples the first electrode to the first channel and the RF source, the second conductor couples the second electrode to the second channel and ground, and the third and fourth conductors couple the temperature sensor to the third and fourth channels, respectively, and to the temperature measurement arrangement.

[0015] In at least some aspects, the at least three channels include a first channel, a second channel, and a third channel, and the at least three conductors include a first conductor coupled to a first electrode, a second conductor coupled to a second electrode, and a third conductor coupled to a temperature sensor, wherein the temperature sensor is also coupled to the first conductor or the second conductor, wherein when the connector of the bipolar RF electrode is electrically coupled to at least one port of the RF generator, the first conductor couples the first electrode to the first channel and an RF source, the second conductor couples the second electrode to the second channel and ground, and the third conductor and the first conductor or the second conductor, respectively, couple the temperature sensor to the third channel and the first channel or the second channel, and a temperature measurement arrangement. In at least some aspects, the RF generator further includes an RF filter coupled between the first channel or the second channel and the temperature measurement arrangement to filter out signals from the RF source.

[0016] In at least some aspects, any of the RF ablation electrodes described above can be used with any of the RF ablation systems described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Non-limiting and non-exhaustive embodiments of the present invention are described with reference to the following drawings.In the drawings, like reference numerals refer to like parts throughout the various views unless otherwise specified.

[0018] For a better understanding of the present invention, reference will be made to the following detailed description, which is to be read in conjunction with the accompanying drawings, in which:

[0019] Figure 1 is a schematic side view of components of one embodiment of an RF ablation system having bipolar RF electrodes;

[0020] Figure 2 is a schematic side view of components of one embodiment of an adapter for coupling a bipolar RF electrode to an RF generator;

[0021] Figure 3 is a schematic diagram of one embodiment of an RF ablation system having an RF generator and bipolar RF electrodes;

[0022] Figure 4 is a schematic diagram of another embodiment of an RF ablation system having an RF generator and bipolar RF electrodes;

[0023] Figure 5A is a schematic side view of a distal portion of one embodiment of a bipolar RF electrode having a metal tube forming one of the electrodes;

[0024] Figure 5B is a schematic cross-sectional view of a portion of one embodiment of a bipolar RF electrode having a metal tube forming one of the electrodes;

[0025] Fig. 6A is a schematic perspective view of a distal tip portion of one embodiment of a bipolar RF electrode;

[0026] Figure 6B is a schematic perspective view of a distal tip portion of another embodiment of a bipolar RF electrode;

[0027] Fig. 7A is a schematic perspective view of one embodiment of a multi-lumen tube for a bipolar RF electrode;

[0028] Figure 7B is a schematic perspective view of another embodiment of a multi-lumen tube for a bipolar RF electrode; and

[0029] Figure 8 is a schematic cross-sectional illustration of a portion of one embodiment of a bipolar RF electrode having a multi-lumen tube. DETAILED DESCRIPTION

[0030] The present disclosure is directed to the field of radio frequency (RF) ablation systems and methods of making and using the same. The present disclosure is also directed to RF ablation systems and methods including bipolar RF electrodes, and methods of making and using the same.

[0031] Many conventional RF generators for pain management support monopolar electrodes with one conductor and a temperature measurement device, such as a thermocouple. The return path is provided by a ground pad attached to the patient's skin. Some RF generators for pain management also support bipolar ablation, in which the conductive tips of two or more separate monopolar electrodes are placed close to each other. One electrode provides power, while the other acts as a return. Each electrode requires a channel on the RF generator.

[0032] As described herein, the RF ablation system may include a bipolar electrode (i.e., an assembly having two electrodes on the same axis) rather than two or more monopolar electrodes. In at least some embodiments, an RF generator previously coupled to a monopolar electrode may be used or adapted for use with a bipolar electrode. Figure 1 One embodiment of an RF ablation system 100 is shown, which includes an RF generator 102, a bipolar RF electrode 104, and a cannula 106. It should be understood that the RF electrode can be a multipolar RF electrode having multiple electrodes on the same axis. It will be appreciated that some embodiments of the RF ablation system can include more or fewer components.

[0033] The cannula 106 includes a cannula hub 108 and a cannula shaft 110. The cannula shaft 110 is hollow for receiving the bipolar RF electrode 104. The bipolar RF electrode 104 includes an electrode shaft 114, a first electrode 112, a second electrode 113, an insulating material 115 separating the first electrode and the second electrode (which may be a part of the electrode shaft), an electrode hub 116, a cable 118 electrically coupled to the electrode shaft 114, and a connector 120 for coupling to at least one port 122 of the RF generator 102 to energize the first electrode 112 or the second electrode 113 (or both) via the cable 118 and the connector 120.

[0034] RF generator 102 may include one or more ports 122 and at least one screen 130. In at least some embodiments, each port 122 is associated with a portion of screen 130 (or a different screen) and may receive a connector 120 from a bipolar RF electrode 104 or from an adapter 109 ( Figure 2 ) connector, as described below. Information such as current, voltage, impedance, status, or the like, or any combination thereof, can be displayed on screen 130. In at least some embodiments, each port 122 corresponds to an independent channel. RF generator 102 optionally includes ground port 121.

[0035] Examples of RF generators and RF ablation systems and methods of making and using RF generators and RF ablation systems can be found, for example, in U.S. Patent Nos. 9,717,552; 9,956,032; 10,111,703; 10,136,937; 10,136,942; 10,136,943; 10,194,971; 10,342,606; 10,363,063; 10,588,687; 10,631,91 5; 10,639,098; and 10,639,101; and U.S. Patent Application Publication Nos. 2014 / 0066917; 2014 / 081260; 2014 / 0121658; 2021 / 0121224; 2021 / 0236191; 2022 / 0202484; 2022 / 0202485; and 2022 / 0226039, all of which are incorporated herein by reference in their entirety.

[0036] The bipolar RF electrode 104 has two conductors (such as Figure 3The bipolar RF electrode includes a conductor 135 (shown), which extends along the cable 118, optionally passes through the electrode shaft 114, and is coupled to the first electrode 112 and the second electrode 113, respectively. One conductor is electrically coupled to one of the electrodes (e.g., electrode 112) and provides power to the electrode, and the other conductor is electrically coupled to the other of the electrodes (e.g., electrode 113) and serves as a return. In at least some embodiments, the bipolar RF electrode includes an insulator 115 between the first electrode 112 and the second electrode 113.

[0037] At least some RF generators provide a single channel at each port 122. In at least some embodiments, the bipolar RF electrode 104 uses a separate channel for each of the two electrodes 112, 113. In at least some embodiments, the RF ablation system 100 may include Figure 2 The adapter 109 shown has a connector 117a connected to the connector 120 of the bipolar RF electrode 104, a conductor (such as a Figure 3 135) and two port connectors 117b for coupling to separate ports 122 of the RF generator 102. This allows one port 122 to energize one of the electrodes (e.g., electrode 112) and the other port 112 to act as a return using another of the electrodes (e.g., electrode 113).

[0038] In at least some embodiments, RF ablation system 100 may include a temperature measurement arrangement and a temperature sensor (eg, a thermocouple or a thermistor), which may be similar to Figure 3 The temperature measurement arrangement 134 and temperature sensor 136, or any other temperature measurement arrangement and temperature sensor used for existing monopolar electrodes of RF ablation systems. In at least some embodiments, power or temperature calculations / measurements can be performed using one or both channels. In at least some embodiments, temperature measurements can be performed using an active electrode channel, and active temperature feedback can be performed using a return electrode channel (or vice versa). In at least some embodiments, resistance or impedance can be measured for one or both channels (i.e., for one or both of electrodes 112, 113). In at least some embodiments, if the temperature, resistance, or impedance exceeds a threshold, a warning or error can be provided to the user by the RF generator, and optionally, RF ablation can be stopped.

[0039] Figure 3 Another embodiment of an RF ablation system 300 is shown having a Figure 1The RF ablation system 100 shown has the same elements except as indicated herein. In the RF ablation system 300, the RF generator 102 includes an RF source 130 (which is included in all RF generators described herein), a ground 132 (which is also included in all RF generators described herein), and a temperature measurement arrangement 134 (which may be included in any RF generator described herein). Figure 3 The connections (e.g., channels) between the RF generator 102 and the connector 120 of the bipolar RF electrode 104 are shown. In this embodiment, there are four different channels: one channel 140a coupled to the RF power source 130, one channel 140b coupled to the ground 132, and two channels 140c, 140d coupled to the temperature measurement arrangement 134.

[0040] Figure 3 Also shown are conductors 135 from connector 120 to first electrode 112 (e.g., a power or active electrode) and second electrode 113 (e.g., a ground or return electrode), as well as conductor 137 to temperature sensor 136. In this embodiment, first electrode 112 is coupled to RF power source 130 on channel 140a through connector 120, and second electrode 113 is coupled to ground 132 on channel 140b through connector 120. (It will be appreciated that in other embodiments, first electrode 112 may be a return electrode, and second electrode 113 may be an active electrode, with appropriate changes to the channels to which the respective electrodes are coupled.)

[0041] The temperature sensor 136 can be, for example, a thermistor, a thermocouple, or the like, or any combination thereof. In at least some embodiments, the temperature sensor 136 is disposed at a power source or active electrode (e.g., Figure 3 The temperature sensor 136 is coupled to the temperature measurement arrangement 134 on the channels 140c, 140d via the connector 120 to obtain an accurate temperature near the area where ablation energy is applied (or initially applied) to the tissue.

[0042] In at least some embodiments, resistance, impedance, voltage, or the like may be measured for one or both channels 140a, 140b (i.e., for one or both electrodes 112, 113). In at least some embodiments, if the resistance, impedance, current, or the like exceeds a threshold, a warning or error may be provided to the user by the RF generator, and optionally, RF ablation may be stopped.

[0043] Figure 4 Another embodiment of an RF ablation system 400 is shown having a Figure 1The RF ablation system 100 is shown with the same elements except as indicated herein. In the RF ablation system 400 , the RF generator 102 includes an RF source 130 , a ground 132 , and a temperature measurement arrangement 134 . Figure 3 The connections (e.g., channels) between the RF generator 102 and the connector 120 of the bipolar RF electrode 104 are shown. In this embodiment, there are three different channels 140a, 140b, 140c: one channel 140a is coupled to the RF power source 130 and the temperature measurement arrangement 134, another channel 140b is coupled to the temperature measurement arrangement 134, and one channel 140c is coupled to the ground 132.

[0044] Figure 4 Also shown are connections from connector 120 to a first electrode 112 (e.g., a power source or active electrode) and a second electrode 113 (e.g., a ground or return electrode), as well as a connection to a temperature sensor 136. In this embodiment, first electrode 112 is coupled to RF power source 130 on channel 140a through connector 120, and second electrode 113 is coupled to ground 132 on channel 140c through connector 120.

[0045] The temperature sensor 136 is coupled to the temperature measurement arrangement 134 through an RF filter 138 to remove signals generated by the RF power source 130. Any suitable type of RF filter may be used. The temperature sensor 136 is coupled to the temperature measurement arrangement 134 on the channel 140a (which is also coupled to the active electrode 112) and the channel 140b through the connector 120. However, it will be appreciated that in other embodiments, the temperature sensor 136 may be coupled to the temperature measurement arrangement 134 on the channel 140b and the channel 140c (which is also coupled to the return electrode 113) through the connector 120.

[0046] In at least some embodiments, resistance, impedance, voltage, or the like may be measured for one or both channels 140a, 140c (i.e., for one or both electrodes 112, 113). In at least some embodiments, if the resistance, impedance, current, or the like exceeds a threshold, a warning or error may be provided to the user by the RF generator, and optionally, RF ablation may be stopped.

[0047] The basivertebral nerve (BVN) is located in the center of the vertebrae in the lower back. The BVN can be difficult to access. The ablation volume of the nerve is large enough to eliminate pain and prevent the nerve from growing back quickly. The vertebral body has considerable hardness and a rough texture, which creates mechanical stress that the electrodes should withstand. In addition, the electrodes must be retrieved at the end of the ablation procedure. Typically, for BVN ablations, the electrodes also navigate sharp turns to avoid negative outcomes such as puncturing the spinal canal. In addition, the electrodes experience forces applied at the hub to overcome friction and obstacles to reach the target treatment location.

[0048] A small curved hole is made in the patient's vertebra using an auxiliary tool by the doctor. The hole diameter is large enough to allow the electrode to be inserted and guided to the target treatment location. In at least some embodiments, the electrode has a relatively high column strength so that the tip can overcome obstacles such as bone fragments.

[0049] In at least some embodiments, the bipolar RF electrode 104 includes a metal tube 140 with a distal end portion 142 having a cutout 144 (eg, a laser cutout- Figure 5A ),like Figure 5A and 5B As shown, this helps to bend the distal portion of the tube. In at least some embodiments, the cutouts 144 form an interrupted spiral pattern to provide curvature and deflection force. Other cutout patterns can be used to provide bending directionality, increased torque strength, or the like. The uncut tube segment 146 provides column strength and can remain straight during insertion and ablation procedures. The distal portion 142 with the cutouts 144 can be bent to follow the curved tunnel within the vertebra. In at least some embodiments, at least a portion (or all) of the distal portion 142 of the metal tube 140 forms one of the electrodes 112, 113 of the bipolar RF electrode 104. In at least some embodiments, a non-conductive sheath 148 (e.g., made of a non-conductive polymer such as silicone, polyester, or polyetheretherketone) covers at least a portion (or all) of the uncut tube segment 146 and can cover a portion of the distal portion 142 (e.g., all but the last 1 to 5 mm of the distal portion 142). In at least some embodiments, the connector 120 ( Figure 3 ) conductor 135( Figure 3 ) is coupled to the electrode hub 116 ( Figure 1 ) rather than extending along the length of the electrode axis 114.

[0050] The bipolar RF electrode 104 also includes a non-conductive spacer 150 and a tip electrode 152, which is separated from the tube 140 by the non-conductive spacer. The insulated conductor extends within the electrode shaft 114 to the tip electrode 152. In at least some embodiments, the non-conductive spacer 150 is curved or longer along one side of the spacer than along the opposite side of the spacer, such as Fig. 6A and Figure 6B 140, or the non-conductive spacer 150, or the tip electrode 152, or any other electrode (or any combination thereof) to facilitate visualization of the energy delivery location using fluoroscopy. The tip electrode 152 can have any suitable shape, including, but not limited to, a round (FIG. 5), a chisel ( Fig. 6A ), inclined plane ( Figure 6B ) or any other suitable shape.

[0051] In at least some embodiments, the bipolar RF electrode 104 ( Figure 1 ) of the electrode axis 114 ( Figure 1 ) includes a multi-lumen tube 160, a portion of which is Fig. 7A and Figure 7B 10 is shown for two different embodiments. In at least some embodiments, the multi-lumen tube 160 is made of a material having a relatively high hardness to provide column strength to the electrode shaft 114. In at least some embodiments, a braid or coil can be used to provide additional column strength to the electrode shaft 114. In at least some embodiments, the multi-lumen tube 160 includes two, three ( Figure 7B ), four ( Fig. 7A ) or more conductor lumens 162, depending on the number of conductors extending along the electrode axis 114 (see, for example, four and three conductor arrangements Figure 3 and Figure 4 In at least some embodiments, conductors 135, 137 ( Figure 3 ) passes along the electrode shaft 114 within the conductor lumen 162 to protect the conductor during bending, implantation, and operation. In at least some embodiments, the multi-lumen shaft 160 also includes a stylet lumen 164 ( Figure 7B ) to enhance the column strength of the multi-lumen shaft 160.

[0052] The distal portion 166 of the bipolar RF electrode 104 includes a first electrode 112 and a second electrode 113. Figure 1 Figure 5 Fig. 6A , Figure 6B and Figure 8In at least some embodiments, the first electrode 112 and the second electrode 113 are disposed on the distal portion 166 of the electrode shaft 114, which does not include the multi-lumen tube 160, such as Figure 8 In at least some embodiments, the distal portion 166 of the electrode shaft 114 is made of a material having a substantially lower hardness than the multi-lumen shaft 160 to facilitate bending of the distal portion of the electrode shaft 114 while the multi-lumen tube 160 remains relatively straight. The first electrode 112 and the second electrode 113 can be separated by a spacer (such as the non-conductive spacer 150 described above). The most distal electrode 113 can be a tip electrode (see FIG. 5, Fig. 6A and Figure 6B ), or there may be a non-conductive tip 167 disposed at the distal end of the distal-most electrode 113, such as Figure 8 shown.

[0053] It will be recognized that this paper aims at Figures 1 to 8 Any combination of features described in the illustrated embodiments, including but not limited to Figure 2 Adapter 109, Figure 3 and Figure 4 Channel and conductor arrangement, Figure 5 to Figure 6B The metal tube 140 and the tip electrode 152 and FIG. 7A to FIG. 8 The multi-lumen tube 160 can be included in any embodiment of the RF ablation system or bipolar RF electrode. The length and diameter of the electrodes 112, 113 and the separation distance between the electrodes can be selected or designed to provide a desired ablation volume.

[0054] The above specification provides a description of the structure, manufacture, and use of the invention. Since many embodiments of the invention can be made without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended.

Claims

1. An RF ablation electrode, comprising: Electrode shaft; a metal tube forming at least a portion of the electrode shaft and comprising a proximal portion and a distal portion, wherein at least the distal portion of the metal tube comprises a plurality of cutouts to facilitate bending of the distal portion, wherein at least a portion of the distal portion of the metal tube comprises a first electrode; a spacer disposed away from the first electrode; a second electrode disposed away from the spacer; connectors; and At least two conductors are electrically coupled to the connector, wherein different ones of the at least two conductors are electrically coupled to the first electrode and the second electrode, respectively.

2. The RF ablation electrode according to claim 2, wherein: The plurality of cutouts are arranged in an interrupted spiral pattern.

3. The RF ablation electrode according to any one of claims 1 or 2, further comprising a non-conductive sheath disposed on at least a proximal portion of the metal tube but not on the first electrode.

4. The RF ablation electrode according to any one of claims 1 to 3, wherein: The plurality of conductors includes a first conductor electrically attached to a proximal portion of the metal tube, or the proximal portion of the metal tube does not include any cutouts.

5. The RF ablation electrode according to any one of claims 1 to 4, wherein the spacer, the first electrode or the second electrode comprises a radiopaque marker.

6. An RF ablation electrode, comprising: an electrode shaft comprising a proximal portion, a distal portion, and a multi-lumen tube extending along at least a portion of the proximal portion of the electrode shaft, the multi-lumen tube defining a plurality of conductor lumens extending along the multi-lumen tube; a first electrode disposed along or coupled to a distal portion of the electrode shaft; a spacer disposed away from the first electrode; a second electrode disposed away from the spacer; Connectors; as well as At least two conductors are electrically coupled to the connector, wherein different ones of the at least two conductors are electrically coupled to the first electrode and the second electrode, respectively, wherein at least a portion of at least one of the at least two conductors extends along at least one of the conductor lumens of the multi-lumen tube.

7. The RF ablation electrode according to claim 6, wherein: The multi-lumen tube has exactly three or four of the conductor lumens, or the multi-lumen tube further includes a stylet lumen that is different in size from the conductor lumens.

8. The RF ablation electrode according to any one of claims 6 or 7, wherein: The multi-lumen tube is made of a material of higher durometer than a material forming a portion of the electrode shaft adjacent the first electrode.

9. The RF ablation electrode according to any one of claims 1 to 8, wherein: The second electrode is a tip electrode or a ring electrode.

10. An RF ablation system, comprising: The RF ablation electrode according to any one of claims 1 to 9; as well as An RF generator is coupled or capable of being coupled to the RF ablation electrode.

11. An RF ablation system, comprising: a bipolar RF electrode comprising an electrode shaft, a first electrode and a second electrode disposed along a distal portion of the electrode shaft, a connector, a first conductor electrically coupled to the first electrode and the connector, and a second conductor electrically coupled to the second electrode and the connector; as well as An adapter comprising an electrode connector configured to be connected to a connector of the bipolar RF electrode, a first port connector and a second port connector configured to be individually connected to different ports of an RF generator, a first adapter conductor configured to electrically couple the electrode connector to the first port connector, and a second adapter conductor configured to electrically couple the electrode connector to the second port connector, wherein when the electrode connector of the adapter is coupled to the connector of the bipolar RF electrode, the first conductor of the bipolar RF electrode is electrically coupled to the first adapter conductor, and the second conductor of the bipolar RF electrode is electrically coupled to the second adapter conductor.

12. The RF ablation system of claim 11, further comprising the RF generator comprising a first port configured to receive the first port connector of the adapter and a second port configured to receive the second port connector of the adapter.

13. An RF ablation system, comprising: an RF generator comprising an RF source, a ground, a temperature measurement arrangement, and at least one port, wherein the RF generator defines at least three channels, wherein the RF source and the ground are electrically coupled to different ones of the at least three channels, and the temperature measurement arrangement is electrically coupled to two of the at least three channels; as well as A bipolar RF electrode comprising an electrode shaft, a first electrode and a second electrode disposed along a distal portion of the electrode shaft, a temperature sensor disposed along the distal portion of the electrode shaft, a connector, and at least three conductors extending along the electrode shaft and electrically coupled to the connector, wherein the first electrode and the second electrode are electrically coupled to different conductors of the at least three conductors, and the temperature sensor is coupled to two of the at least three conductors, wherein the connector of the bipolar RF electrode is configured to be electrically coupled to at least one of the at least one port of the RF generator such that, when coupled, the first electrode is electrically coupled to the RF source, the second electrode is electrically coupled to the ground, and the temperature sensor is electrically coupled to the temperature measurement arrangement.

14. The RF ablation system according to claim 13, wherein: The at least three channels include a first channel, a second channel, a third channel, and a fourth channel, and the at least three conductors include a first conductor coupled to the first electrode, a second conductor coupled to the second electrode, and third and fourth conductors coupled to the temperature sensor, wherein, when the connector of the bipolar RF electrode is electrically coupled to at least one port of the RF generator, the first conductor couples the first electrode to the first channel and the RF source, the second conductor couples the second electrode to the second channel and the ground, and the third and fourth conductors couple the temperature sensor to the third and fourth channels and the temperature measurement arrangement, respectively.

15. The RF ablation system according to claim 13, wherein: The at least three channels include a first channel, a second channel, and a third channel, and the at least three conductors include a first conductor coupled to the first electrode, a second conductor coupled to the second electrode, and a third conductor coupled to the temperature sensor, wherein the temperature sensor is also coupled to the first conductor or the second conductor, wherein, when the connector of the bipolar RF electrode is electrically coupled to at least one port of the RF generator, the first conductor couples the first electrode to the first channel and the RF source, the second conductor couples the second electrode to the second channel and the ground, and the third conductor and the first conductor or the second conductor couple the temperature sensor to the third channel and the first channel or the second channel, respectively, and the temperature measurement arrangement, wherein the RF generator optionally also includes an RF filter coupled between the first channel or the second channel and the temperature measurement arrangement to filter out signals from the RF source.

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