Flexible circuit device for thermocouples in catheters

Abstract

To provide a catheter. [Solution] The catheter comprises a shaft assembly, an end effector, and a flexible circuit. The end effector is located at the distal end of the shaft assembly and includes a tip member. The tip member is operable to apply electrical energy to tissue. The tip member defines a hole having an inner side wall. The flexible circuit includes a thermocouple located within the hole in the tip member. The thermocouple is configured to sense the temperature of the tip member. The flexible circuit further includes a deformable feature that elastically biases the thermocouple toward the inner side wall of the hole.

Description

Background Art

[0001] Cardiac arrhythmias such as atrial fibrillation occur when regions of heart tissue conduct electrical signals abnormally. Treatments for arrhythmias include surgically disrupting such signal conduction pathways. By selectively ablating heart tissue by applying energy (e.g., alternating current or direct current energy), it may be possible to stop or modify the propagation of unwanted electrical signals from one part of the heart to another. The ablation process can provide a barrier to unwanted electrical pathways by forming an electrically insulating lesion or scar tissue that effectively blocks the communication of abnormal electrical signals across the tissue.

[0002] In some procedures, a catheter having one or more electrodes can be used to provide ablation within the cardiovascular system. The catheter can be inserted into a major vein or artery (e.g., the femoral artery) and then advanced to position the electrodes within the heart or within a cardiovascular structure adjacent to the heart (e.g., a pulmonary vein). One or more electrodes can be placed in contact with heart tissue or other vascular tissue and then ablated by operating with electrical energy. In some cases, the electrodes may be bipolar. In some other cases, unipolar electrodes can be used in conjunction with a ground pad or in conjunction with another reference electrode in contact with the patient. Perfusion can be used to draw heat away from the ablation component of the ablation catheter and prevent the formation of thrombi near the ablation site.

[0003] Examples of ablation catheters include U.S. Patent No. 10,743,932, issued on August 18, 2020, entitled "Integrated Ablation System using Catheter with Multiple Irrigation Lumens" (the disclosure thereof is incorporated herein by reference in its entirety); U.S. Patent No. 10,660,700, issued on May 26, 2020, entitled "Irrigated Balloon Catheter with Flexible Circuit Electrode Assembly" (the disclosure thereof is incorporated herein by reference in its entirety); U.S. Patent No. 11,559,349, issued on January 24, 2023, entitled "Ablation Catheter with a Flexible Printed Circuit Board" (the disclosure thereof is incorporated herein by reference in its entirety); and "Catheter with Bipole Electrode Spacer and Related" issued on July 7, 2020. These methods are described in U.S. Patent No. 10,702,177, entitled “Methods” (the entire disclosure of which is incorporated herein by reference); U.S. Patent No. 10,130,422, entitled “Catheter with Soft Distal Tip for Mapping and Ablating Tubular Region,” issued on 20 November 2018 (the entire disclosure of which is incorporated herein by reference); U.S. Patent No. 8,956,353, entitled “Electrode Irrigation Using Micro-Jets,” issued on 17 February 2015 (the entire disclosure of which is incorporated herein by reference); and U.S. Patent No. 9,801,585, entitled “Electrocardiogram Noise Reduction,” issued on 31 October 2017 (the entire disclosure of which is incorporated herein by reference).

[0004] Some catheter ablation procedures may be performed after identifying the tissue area to be targeted for ablation using electrophysiological (EP) mapping. Such EP mapping may include the use of a sensing electrode on a catheter (e.g., the same catheter used to perform the ablation, or a dedicated mapping catheter). Such a sensing electrode can monitor electrical signals emanating from conductive endocardial tissue to pinpoint the location of abnormal conductive tissue sites causing arrhythmias. An example of an EP mapping system is described in U.S. Patent No. 5,738,096, entitled "Cardiac Electromechanics," issued on April 14, 1998 (the disclosure thereof is incorporated herein by reference in its entirety). Examples of EP mapping catheters are described in U.S. Patent No. 9,907,480, entitled "Catheter Spine Assembly with Closely-Spaced Bipole Microelectrodes," issued on March 6, 2018 (the disclosure thereof is incorporated herein by reference in its entirety); U.S. Patent No. 10,130,422, entitled "Catheter with Soft Distal Tip for Mapping and Ablating Tubular Region," issued on November 20, 2018 (the disclosure thereof is incorporated herein by reference in its entirety); and U.S. Patent No. 10,702,177, entitled "Catheter with Bipole Electrode Spacer and Related Methods," issued on July 7, 2020 (the disclosure thereof is incorporated herein by reference in its entirety).

[0005] When using an ablation catheter, it may be desirable to monitor the temperature in one or more distal tip regions of the catheter, which may further indicate the temperature of the tissue in contact with the distal tip of the catheter. Temperature monitoring may be performed via one or more thermocouples incorporated into the catheter. Each thermocouple may be capable of displaying the measured temperature to a processor. In some cases, thermocouples for catheters may be difficult to manufacture and position for accurate temperature readings due to their small size. This difficulty tends to result in undesirable high waste rates during manufacturing.

[0006] Although several catheter systems and methods have been implemented and used, it is believed that no one prior to the present inventors has implemented or used the present invention described, illustrated, and claimed herein. [Brief explanation of the drawing]

[0007] The following drawings and detailed description are intended to be illustrative only and are not intended to limit the scope of the invention as envisioned by the inventors. [Figure 1] This diagram shows a schematic representation of the medical procedure involving the insertion of a catheter assembly catheter into a patient. [Figure 2] Figure 1 is a perspective view of the distal portion of the catheter, with additional components shown in schematic form. [Figure 3] Figure 1 shows an exploded perspective view of the catheter tip and flexible circuit. [Figure 3A] A portion of the tip member is shown in cross-section, and a perspective view of the tip member of Figure 3 with the flexible circuit of Figure 3 inserted is shown. [Figure 4] Figure 3A shows a cross-sectional side view of the tip member and flexible circuit shown in Figure 3, along line 4-4. [Figure 5] Figure 1 shows an exploded perspective view of the catheter tip, flexible circuit, and printed circuit board. [Figure 6] Figure 3 shows a cross-sectional side view of the distal portion of the flexible circuit. [Figure 7] Figure 3A shows a cross-sectional end view of the tip member and flexible circuit shown in Figure 3, along line 7-7. [Figure 8] Figure 3 shows an exploded perspective view of the tip member and the second flexible circuit, in which the distal portion of the fourth flexible circuit is pre-folded. [Figure 8A] Figure 8 shows a cross-sectional view of the tip member of Figure 3, into which the second flexible circuit is inserted. [Figure 9] Figure 8A shows a cross-sectional side view of the tip member and the second flexible circuit of Figure 8, along line 9-9. [Figure 10] Figure 3 shows an exploded perspective view of the tip member and the third flexible circuit, in which the distal portion of the fourth flexible circuit is pre-folded. [Figure 10A] Figure 10 shows a cross-section of the tip member, and Figure 3 shows a perspective view of the tip member into which the third flexible circuit is inserted. [Figure 11] Figure 10A shows a cross-sectional end view of the tip member and the third flexible circuit of Figure 10, along line 11-11. [Figure 12] Figure 3 shows an exploded perspective view of the tip member and the fourth flexible circuit, in which the distal portion of the fourth flexible circuit is pre-folded. [Figure 12A] Figure 3 shows a cross-sectional view of the tip member, and Figure 12 shows another exploded perspective view of the fourth flexible circuit. [Figure 13] Figure 12A shows a cross-sectional end view of the tip member and the fourth flexible circuit of Figure 12, along line 13-13. [Figure 14] Figure 3 shows an exploded perspective view of the tip member and the fifth flexible circuit, in which the distal portion of the fourth flexible circuit is pre-folded. [Figure 14A] Figure 14 shows a cross-section of the tip member, and Figure 3 shows a perspective view of the tip member into which the fifth flexible circuit is inserted. [Figure 15]Figure 14A shows a cross-sectional end view of the tip member and the fifth flexible circuit of Figure 14, along line 15-15. [Modes for carrying out the invention]

[0008] The following description of specific embodiments of the present invention should not be used to limit the scope of the invention. The drawings are not necessarily to scale, illustrate selected embodiments, and are not intended to limit the scope of the invention. The detailed description is illustrative, not limiting, and illustrates the principles of the invention as an example. Other embodiments, features, aspects, forms, and advantages of the invention will become apparent to those skilled in the art from the following description, which is one of the best modes intended to carry out the invention as an example. As will be recognized, the invention can be made into other different or equivalent embodiments without departing from the invention. Accordingly, the drawings and description should be considered illustrative, not limiting.

[0009] Any one or more of the teachings, expressions, modifications, examples, etc., described herein may be combined with any one or more of the other teachings, expressions, modifications, examples, etc., described herein. Therefore, the teachings, expressions, modifications, examples, etc., described below should not be considered in isolation. Various preferred ways in which the teachings herein may be combined will be readily apparent to those skilled in the art in view of the teachings herein. Such modifications and variations are intended to be included within the claims.

[0010] Where used herein, the terms “approximately” or “about” for any number or range indicate a preferred dimensional tolerance that enables some or all of the components to function for the intended purposes described herein. More specifically, “approximately” or “about” may refer to a range of values ​​within ±10% of the enumerated values, while “about 90%” may refer to a range of values ​​between 81% and 99%. In addition, where used herein, the terms “patient,” “host,” “user,” and “subject” refer to any human or animal subject, and while the use of the present invention in a human patient represents a preferred embodiment, it is not intended to limit the system or method to human use.

[0011] I. Overview of Ablation Catheter System Implementation Examples Figure 1 shows an exemplary medical procedure and associated components of a cardiac ablation catheter system that may be used to perform cardiac ablation as described above. Specifically, Figure 1 shows a physician (PH) grasping the handle (110) of a catheter assembly (100), with an end effector (140) of the catheter (120) (shown in Figure 2, but not in Figure 1) of the catheter assembly (100) placed inside the patient (PA) to ablate tissue inside or near the heart (H) of the patient (PA). As used herein, the term “to ablate” is intended to include radiofrequency ablation, irreversible electroporation, or any other appropriate ablation therapy. The catheter assembly (100) includes a handle (110), a catheter (120) extending distally from the handle (110), and an end effector (140) located at the distal end of the catheter (120).

[0012] As will be described in more detail below, the end effector (140) of the present embodiment is operable to deliver electrical energy to a target tissue site, provide an EP mapping function, track an external force applied to the end effector (140), track the position of the end effector (140), and disperse an irrigation fluid. The user input mechanism (190) is configured to deflect the end effector (140) and the distal portion of the catheter (120) away from the longitudinal central axis (L-L).

[0013] As shown in FIG. 2, the catheter (120) includes an elongated flexible sheath (122), and the end effector (140) is disposed at the distal end of the sheath (122). The end effector (140) and various components housed within the sheath (122) will be described in more detail below. The catheter assembly (100) is coupled to the induction drive system (10) via a cable (30). The catheter assembly (100) is also coupled to a fluid source (42) via a fluid conduit (40). A set of field generators (20) is positioned below the patient (PA) and is coupled to the induction drive system (10) via another cable (22). The field generator (20) is merely optional.

[0014] The induction drive system (10) of the present embodiment includes a console (12) and a display (18). The console (12) includes a first driver module (14) and a second driver module (16). The first driver module (14) is coupled to the catheter assembly (100) via a cable (30). In some variations, the first driver module (14) is operable to receive an EP mapping signal obtained via the microelectrodes (138) of the end effector (140), as will be described in more detail below. The console (12) includes a processor (not shown) that processes such EP mapping signals and thereby performs EP mapping known in the art.

[0015] The first driver module (14) of this embodiment is operable to supply RF power to the distal tip member (142) of the end effector (140) and is further operable to ablate tissue, as will be described in more detail below. The second driver module (16) is coupled to the field generator (20) via a cable (22). The second driver module (16) is operable to activate the field generator (20) to generate an alternating magnetic field around the heart (H) of the patient (PA). For example, the field generator (20) may include a coil that generates an alternating magnetic field within a predetermined working volume that includes the heart (H).

[0016] The first driver module (14) is also operable to receive a position indication signal from a navigation sensor assembly (not shown) within the end effector (140). In such a variant, the processor of the console (12) is also operable to process the position indication signal from the navigation sensor assembly and thereby determine the position of the end effector (140) within the patient (PA). By way of example only, the navigation sensor assembly may include one or more coils operable to generate a signal indicative of the position and orientation of the end effector (140) within the patient (PA). The coils may be configured to generate an electrical signal in response to the presence of an alternating electromagnetic field generated by the field generator (20). Other components and techniques that may be used to generate real-time position data associated with the end effector (140) include, but are not limited to, wireless triangulation, acoustic tracking, optical tracking, inertial tracking, and the like. Alternatively, the end effector (140) may not include a navigation sensor assembly.

[0017] The display (18) is coupled to the processor of the console (12) and is operable to render images of the patient's anatomical structure. Such images may be obtained based on a set of images (e.g., CT scan or MRI scan, 3D map, etc.) acquired before or during surgery. The diagram of the patient's anatomical structure provided via the display (18) may also change dynamically based on signals from the navigation sensor assembly of the end effector (140). For example, as the end effector (140) of the catheter (120) moves within the patient (PA), the corresponding position data from the navigation sensor assembly allows the processor of the console (12) to update the diagram of the patient's anatomical structure in the display (18) in real time, showing the area of ​​the patient's anatomical structure around the end effector (140) as the end effector (140) moves within the patient (PA). Furthermore, the console (12) processor can drive the display (18) to indicate the location of abnormal conductive tissue sites, as detected by electrophysiological (EP) mapping using the end effector (140) or by other means (e.g., by using a dedicated EP mapping catheter). The console (12) processor can also drive the display (18) to superimpose the current position of the end effector (140) onto an image of the patient's anatomical structure, for example, by superimposing illumination dots, crosshairs, a graphic representation of the end effector (140), or some other form of visual display.

[0018] The fluid source (42) in this embodiment includes a bag containing saline solution or some other suitable irrigation fluid. The conduit (40) includes a flexible tube further coupled to a pump (44) that is operable to selectively drive fluid from the fluid source (42) to the catheter assembly (100). Such irrigation fluid may be discharged through an opening (158) in the distal tip member (142) of the end effector (140). Such irrigation can be performed in any preferred manner that is apparent to those skilled in the art in light of the teachings herein.

[0019] II. Examples of End Effectors for Catheter Assemblies Figures 2–4 show in more detail exemplary components of the end effector (140) and other components of the distal portion of the catheter (120). The end effector (140) includes a distal tip member (142) and a distal portion of a flexible circuit (200) having a thermocouple assembly (210). A pair of push-pull cables (160, 170) extend along the length of the catheter (120) and reach the end effector (140). The push-pull cables (160, 170) allow the physician (PH) to selectively deflect the end effector (140) laterally away from the longitudinal central axis (LL), thereby allowing the physician (PH) to actively steer the end effector (140) within the patient (PA). Various mechanisms that may be used to drive the push-pull cables (160, 170) in a manner that is simultaneously opposed longitudinally will be apparent to those skilled in the art by considering the teachings herein. The flexible sheath (122) surrounds a portion of the push-pull cables (160, 170) and a portion of the flexible circuit (200).

[0020] As shown in Figures 3 and 4, the distal tip member (142) of this embodiment is conductive and includes a cylindrical body (156) having a dome tip (146). Multiple openings (158) are formed through the cylindrical body (156) and communicate with the hollow interior of the distal tip member (142). Thus, the openings (158) allow the irrigation fluid to communicate from the inside of the distal tip member (142) through the cylindrical body (156) to the outside. The cylindrical body (156) and the dome tip (146) are also operable to apply RF electrical energy to tissue, thereby ablating the tissue. Such RF electrical energy can be transmitted from the first driver module (14) to the cylindrical body (156) via a cable (30) and any number of conductive components (not shown) interposed between the cylindrical body (156) and the cable (30) (e.g., wires, traces of a flexible circuit).

[0021] As best seen in Figures 3 and 4, the distal tip member (142) of this embodiment also includes a first set of holes (162) and a second set of holes (164). The holes (162, 164) are formed within the cylindrical body (156) and are angularly spaced apart from each other about the longitudinal central axis (LL) in an alternating arrangement. Hole (162) terminates distally within the cylindrical body (156), and as a result, hole (162) constitutes a blind hole that does not extend through the dome tip (146). Hole (164) extends completely through the cylindrical body (156) and the dome tip (146). Hole (162) receives a thermocouple assembly (210) configured to provide temperature sensing capability, as will be described in more detail below. Hole (164) receives an EP mapping electrode (138). The EP mapping microelectrode (138) is configured to pick up potentials from the tissue in contact with the EP mapping microelectrode (138). The first driver module (14) processes the EP mapping signal and can provide the physician (PH) with corresponding feedback indicating the location of abnormal electrical activity, in accordance with the teachings of various references cited herein.

[0022] As described above, the catheter assembly (100) is configured to allow irrigation fluid to be transmitted from a fluid source (42) to the catheter (120) via a fluid conduit (40), thereby providing discharge of the irrigation fluid through an opening (158) in the distal tip member (142). In some modifications, the fluid path for the irrigation fluid includes an irrigation tube (not shown) located within the sheath (122) and coupled with the fluid conduit (40) (for example, at the handle (110) of the catheter assembly (100). Such an irrigation tube may extend along the length of the catheter (120) to reach an end effector (140). In some modifications, the irrigation fluid may be transmitted from the distal end of the irrigation tube through a central passage formed by aligned central apertures of the features described above, and may eventually reach the interior of the distal tip member (142) before flowing out through the opening (158).

[0023] III. First Embodiment of a Flexible Circuit As described above, some variations of thermocouples may be difficult to manufacture, may be difficult to position for accurate temperature readings due to their small size, and / or may tend to result in undesirable high waste rates during manufacturing. However, the thermocouple assembly (210) of this embodiment and their arrangement within the end effector (140) may tend to mitigate such problems. In other words, the configuration and arrangement of the thermocouple assembly (210) within the end effector (140) may tend to offer faster and / or more cost-effective manufacturing compared to conventional thermocouples, may tend to offer easier positioning for accurate temperature readings compared to conventional thermocouples, and / or may tend to result in lower waste rates during manufacturing compared to conventional thermocouples.

[0024] Figures 3 and 4 show the distal end of a flexible circuit (200) containing a thermocouple assembly (210) positioned inside a hole (162) in the distal tip member (142). Although only one flexible circuit (200) is shown, three flexible circuits (200) (or any other suitable number of flexible circuits (200)) may be provided, with the thermocouple assembly (210) of each flexible circuit (200) positioned inside the respective holes (162) of the distal tip member (142). In some variations, the three separate flexible circuits (200) may extend separately from each other along the length of the sheath (122). In some other variations, the three flexible circuits (200) may be joined together within the sheath (122) (for example, near the end effector (140)) or within the end effector (140) to form a single flex circuit which may then extend along the remaining proximal length of the sheath (122).

[0025] The thermocouple assembly (210) of this embodiment includes a conductive first trace (212), a conductive second trace (215), and a conductive third trace (219). The first trace (212) and the second trace (215) extend along the upper surface of an electrically insulating substrate layer (217). As an example, the substrate layer (217) may include polyimide and / or any other suitable material. The third trace (219) extends along the lower surface of the substrate layer (217). The traces (212, 215, 219) and the substrate layer (217) extend along the length of the sheath (122). These features of the flexible circuit (200) are flexible to allow the catheter (120) to be easily bent during manipulation by a physician (PH), such as when the catheter (120) passes through a tortuous path within the patient (PA) and when the physician (PH) drives deflection of the distal region of the catheter (120).

[0026] The distal end of the first trace (212) includes a first thermal junction (213), while the distal end of the second trace (215) includes a second thermal junction (216). The thermocouple assembly (210) is sized to fit inside the hole (162) with the first and second thermal junctions (213, 216) facing radially outward. As shown in Figure 4, when the thermocouple assembly (210) is fully inserted into the hole (162), proper positioning can be achieved with the distal end of the thermocouple assembly (210) just proximal to the dome tip (146).

[0027] As shown in Figures 4 and 6-7, the first thermal junction (213) is electrically coupled to the third trace (219) via a joint (223). Meanwhile, the second thermal junction (216) is electrically coupled to the third trace (219) via a joint (225). The joints (223, 225) penetrate the entire thickness of the insulating layer 217. In this embodiment, each of the first trace (212) (including the first thermal junction (213)) and the second trace (215) (including the second thermal junction (216)) comprises a first conductive material (e.g., copper), while the third trace (219) comprises a second conductive material (e.g., constantan or a copper-nickel alloy). Due to differences in conductive materials, temperature changes at the joints (223, 225) provide temperature gradients between the first trace (212) and the third trace (219), and between the second trace (215) and the third trace (219), respectively. These temperature gradients can generate thermoelectric voltages proportional to the temperature difference between the distal ends of the first trace (212) and the second trace (215) and the corresponding regions of the third trace (219). Such thermoelectric voltages may be read by the processor of the console (12), as will be described in detail below. It should also be understood that these temperature changes at the joints (223, 225) can be caused by temperature changes at the thermal junctions (213, 216), which can be induced by heating or cooling of the distal tip member (142).

[0028] In this example, both thermal junctions (213, 216) are electrically coupled to the third trace (219) via their respective joints (223, 225). However, in some other modifications, a fourth trace separate from the third trace (219) may be provided, located beneath the insulating layer (217). In some such modifications, the first thermal junction (213) is electrically coupled to the third trace (219) via joint (223). Meanwhile, the second thermal junction (216) is electrically coupled to the fourth trace via joint (225). In such modifications, the fourth trace may comprise a conductive material different from that of the second trace (215).

[0029] In some variations, at least a portion of each trace (212, 215) and thermal junction (213, 216) is coated with an electrically insulating coating (not shown) to electrically insulate the traces (212, 215) and thermal junction (213, 216) from the distal tip member (142). Nevertheless, such an electrically insulating coating may be thermally conductive so that the thermal junction (213, 216) is in thermal communication with the distal tip member (142). Specifically, the thermal junction (213, 216) may be in thermal contact with the inner sidewall of the hole (162) without being in electrical communication with the inner sidewall of the hole (162), while maintaining thermal communication with the inner sidewall of the hole (162). Additional features of the thermocouple assembly (210) that may further promote the thermal coupling between the thermal junction (213, 216) and the distal tip member (142) are described in more detail below.

[0030] As shown in Figure 5, the proximal end (230) of the flexible circuit (200) includes solder pads (244, 245, 246) arranged in a linear row. The first trace (212) is electrically connected to solder pad (244), the second trace (215) is electrically connected to solder pad (246), and the third trace (216) is electrically connected to solder pad (245). A printed circuit board (PCB) (240) is coupled to the proximal end (230) of the flexible circuit (200). Specifically, the PCB (240) includes a pair of solder pads (242) electrically connected to each of the solder pads (244, 245, 246) of the flexible circuit (200). The PCB (240) may be positioned within an end effector (140), an elongated flexible sheath (122), or a handle (110). The PCB (240) is further electrically coupled to the processor of the console (12) via a cable (30) and any number of conductive components (not shown) interposed between the PCB (240) and the cable (30) (e.g., wires, traces of a flexible circuit). Thus, the PCB (240), the cable (30), and the interposed conductive components provide a path for voltage communication from the thermocouple assembly (210) to the processor of the console (12). This allows the processor of the console (12) to process data indicating temperature picked up via the thermocouple assembly (210), thereby sensing the temperature of the end effector (140), which may further indicate the temperature of the end effector (140) in contact with the tissue.

[0031] The end effector (140) may include several separate thermocouple assemblies (210) angularly spaced apart from one another within the distal tip member (142), with each thermocouple assembly (210) positioned within its respective hole (162). Each thermocouple assembly (210) may be incorporated into its own individual flexible circuit (200). Each flexible circuit (200) may also be coupled to its own PCB (240). Alternatively, each flexible circuit (200) may be mounted on a common PCB (240), which has several rows of PCB pads (242) complementing the number of thermocouple assemblies (210). As an example only, if the PCB (240) is positioned in either the handle (110) or the proximal portion of an elongated flexible sheath (122), the flexible circuit (200) may extend to more than 2 meters. Each flexible circuit (200) may be the same length as any other flexible circuit (200). By electrically communicating the PCB (240) separately with each thermocouple assembly (210) of each flexible circuit (200), the PCB (240) may be able to distinguish temperature readings across the distal tip member (142) and communicate these readings to the processor on the console (14). The flexible circuit (200) may also include a reference lead (not shown) extending from a solder pad (245) to the thermocouple assembly (210), which may act to detect signal noise that may be later removed or taken into consideration when evaluating the voltage reading of the thermocouple assembly (210).

[0032] The PCB (240) may comprise a flat single or multilayer circuit board, which allows the flexible circuits (200) to be twisted relative to each other and attached to the distal end member (142), and also positions each thermocouple assembly (210) at an angle radially outward as described above. In this embodiment, considering that the length of the flexible circuits (200) is greater than the diameter of the elongated flexible sheath (122), bending of the elongated flexible sheath (122) may tend to pull each flexible circuit (200) to some extent relative to the distal end member (142). The adhesive holding the thermocouple assembly (210) inside the hole (162) may be sufficient to resist the pulling of the thermocouple assembly (210) out of the hole when the flexible circuit (200) is pulled due to bending of the sheath (122). To further ensure that there is little to no tension in the thermocouple assembly (210), the flexible circuits (200) may also be longer than the length between the PCB (240) and the holes (162), thereby providing slack to accommodate changes induced by bending of the effective length of each flexible circuit (200). In other words, the flexible circuits (200) may be bundled along the length from the PCB (240) to the holes (162).

[0033] As shown in Figures 4 to 7, the region of the flexible circuit (200) forming the thermocouple assembly (210) further includes an additional electrical insulating spacer layer (221) positioned beneath the third trace (219). Thus, the third trace (219) is interposed between the layers (217, 221). As an example only, the spacer layer (221) may include polyimide and / or any other suitable material. In this example, the spacer layer (221) is substantially thicker than the substrate layer (217). Due to the presence of the spacer layer (221), the thermocouple assembly (210) is made larger than the hole (162), and as a result, at least a portion of the thermocouple assembly (210) must be compressed or otherwise deformed in order for the thermocouple assembly (210) to fit into the hole (162). In this embodiment, the spacer layer (221) is compressible, and as a result, the outer corners of the spacer layer (221) deform relative to the inner sidewall of the hole (162), as shown in Figure 7. The spacer layer (221) may also be elastically biased toward an undeformed state, and as a result, compression of the spacer layer (221) within the hole (162) may tend to provide a firm fixation of the thermocouple assembly (210) within the hole (162). Furthermore, such compression of the spacer layer (221) within the hole (162) may tend to bias the upper part of the thermocouple assembly (210) radially outward with respect to the longitudinal central axis (LL). This effect may minimize the distance between the thermal junctions (213, 216) and the outer surface of the cylindrical body (156), which may maximize the sensitivity of the thermal junctions (213, 216) to the temperature of the cylindrical body (156) and the tissue in contact with the cylindrical body (156). This maximizes the sensitivity of the joint (223, 225) to the temperature of the cylindrical body (156) and the tissue in contact with the cylindrical body (156). Thus, the spacer layer (221) can facilitate thermal conductivity between the thermocouple assembly (210) and the cylindrical body (156).

[0034] The thermocouple assembly (210) may be adequately secured within the hole (162) by friction, as described above, but the securing of the thermocouple assembly (210) within the hole (162) may be further supplemented with an adhesive. As merely an example, such an adhesive may be provided by a thermoplastic polyurethane elastomer that is introduced into the hole (162) after the thermocouple assembly (210) has fully seated within the hole (162). As merely another example, such a thermoplastic polyurethane elastomer may be doped with diamond powder and cured with ultraviolet light. Alternatively, any other suitable type of adhesive may be used, and the thermocouple assembly (210) may be joined to the distal tip member (142) using any other suitable process.

[0035] IV. Second Embodiment of Flexible Circuit Figures 8 and 9 show a second embodiment of flexible circuit (300) which may be substantially identical in form and function to flexible circuit (200), except for any differences described below. Thus, flexible circuit (200) may be replaced by flexible circuit (300). Similar to flexible circuit (200), the flexible circuit (300) in this example includes a thermocouple assembly (310) comprising a conductive first trace (312), a conductive second trace (315), and a conductive third trace (321). The first trace (312) and the second trace (315) extend along the upper surface of an electrically insulating substrate layer (317). As an example, the substrate layer (317) may include polyimide and / or any other suitable material. The third trace (321) extends along the lower surface of the substrate layer (317). The traces (312, 315, 321) and substrate layer (317) extend along the length of the sheath (122).

[0036] The distal end of the first trace (312) includes a first thermal junction (313), while the distal end of the second trace (315) includes a second thermal junction (316). The first thermal junction (313) is electrically coupled to the third trace (321) via a joint (323). The second thermal junction (316) is electrically coupled to the third trace (321) via a joint (325). The joints 323 and 325 penetrate the entire thickness of the substrate layer 317. In this embodiment, each of the first trace (312) (including the first thermal junction (313)) and the second trace (315) (including the second thermal junction (316)) comprises a first conductive material (e.g., copper), while the third trace (321) comprises a second conductive material (e.g., constantan or a copper-nickel alloy). Due to the differences in conductive materials, temperature changes at the joints (323, 325) provide temperature gradients between the first trace (312) and the third trace (321), and between the second trace (315) and the third trace (321), respectively. These temperature gradients can generate thermoelectric voltages. Thus, the thermocouple assembly (310) can provide temperature sensing in a similar manner to that described above with respect to the thermocouple assembly (210).

[0037] As shown in Figures 8A and 9, the electrical insulating coating (329) may be positioned over at least a portion of the thermal junctions (313, 316) and traces (312, 315). In some cases, the coating (329) extends further along the length of the traces (312, 315). The coating (329) electrically insulates the traces (312, 315) and thermal junctions (313, 316) from the distal tip member (142). Nevertheless, the coating (329) is thermally conductive, and as a result, the thermal junctions (313, 316) are in thermal communication with the distal tip member (142). Specifically, the thermal junctions (313, 316) can be in thermal contact with the inner sidewall of the hole (162) without being in electrical communication with the inner sidewall of the hole (162), while maintaining thermal communication with the inner sidewall of the hole (162).

[0038] The flexible circuit (300) in this example further includes a distal portion (318) of a substrate layer (317) that extends distally beyond the thermal junctions (313, 316). As shown in Figure 8A, the distal portion (318) may be folded proximal before the thermocouple assembly (310) is inserted into the hole (162). The folded distal portion (318), like the partially compressed spacer layer (221) of the flexible circuit (200), acts as a spring, elastically biasing the thermocouple assembly (310) radially outward with respect to the longitudinal central axis (LL). This effect can minimize the distance between the thermal junctions (313, 316) and the outer surface of the cylindrical body (156), which can maximize the sensitivity of the thermal junctions (313, 316) to the temperature of the cylindrical body (156) and the tissue in contact with the cylindrical body (156). This maximizes the sensitivity of the joint (323, 325) to the temperature of the cylindrical body (156) and the tissue in contact with the cylindrical body (156). The folded distal portion (318) can therefore facilitate thermal conductivity between the thermocouple assembly (310) and the cylindrical body (156).

[0039] Furthermore, the folded distal portion (318) may tend to provide fixation of the thermocouple assembly (310) within the hole (162) by extending the effective cross-sectional profile of the thermocouple assembly (310). In some cases, the elastic bias of the folded distal portion (318) biases the distal portion (318) toward a straight / unfolded configuration, as a result the distal portion (318) abuts against the inner sidewall of the hole (162), thereby increasing the friction for fixing the thermocouple assembly (310) within the hole (162).

[0040] The positioning and securing of the thermocouple assembly (310) within the hole (162) may be further supplemented with an adhesive (327) to bond the flexible circuit (300) to the distal tip member (142). In some cases where the adhesive is used, although not shown in these drawings, at least a portion of the adhesive may occupy the space formed between the folded distal portion (318) and the underside of the third trace (321) and the substrate layer (317) (or the underside of an additional electrical insulation layer (not shown) located beneath the third trace (321)). In just one example, such an adhesive may be provided by a thermoplastic polyurethane elastomer introduced into the hole (162) after the thermocouple assembly (310) has fully seated within the hole (162). In just another example, such a thermoplastic polyurethane elastomer may be doped with diamond powder and cured with ultraviolet light. Alternatively, any other suitable type of adhesive may be used, and any other suitable process may be used to bond the thermocouple assembly (310) to the distal tip member (142).

[0041] V. Third embodiment of a flexible circuit Figures 10-11 show a third embodiment of a flexible circuit (400) which may be substantially identical in form and function to the flexible circuits (200, 300) except for any differences described below. Thus, the flexible circuit (200) may be replaced by the flexible circuit (400). Similar to the flexible circuit (200), the flexible circuit (400) in this example includes a thermocouple assembly (410) comprising a conductive first trace (412), a conductive second trace (415), and a conductive third trace (421). The first trace (412) and the second trace (415) extend along the upper surface of an electrically insulating substrate layer (417). As an example, the substrate layer (417) may include polyimide and / or any other suitable material. The third trace (421) extends along the lower surface of the substrate layer (417). The traces (412, 415, 421) and substrate layer (417) extend along the length of the sheath (122).

[0042] The distal end of the first trace (412) includes a first thermal junction (413), while the distal end of the second trace (415) includes a second thermal junction (416). The first thermal junction (413) is electrically coupled to the third trace (421) via a joint (not shown). The second thermal junction (416) is electrically coupled to the third trace (421) via a joint (425). The joint (425) penetrates the entire thickness of the substrate layer (417). In this embodiment, each of the first trace (412) (including the first thermal junction (413)) and the second trace (415) (including the second thermal junction (416)) comprises a first conductive material (e.g., copper), while the third trace (421) comprises a second conductive material (e.g., constantan or a copper-nickel alloy). Due to the differences in conductive materials, the temperature change at the junction (425) provides temperature gradients between the first trace (412) and the third trace (421), and between the second trace (415) and the third trace (421), respectively. These temperature gradients can generate thermoelectric voltages. Thus, the thermocouple assembly (410) can provide temperature sensing in a similar manner to that described above with respect to the thermocouple assembly (210).

[0043] As shown in Figures 10A and 11, the electrical insulating coating (429) may be positioned over at least a portion of the thermal junctions (413, 416) and traces (412, 415). In some cases, the coating (429) may extend further along the length of the traces (412, 415). The coating (429) electrically insulates the traces (412, 415) and thermal junctions (413, 416) from the distal tip member (142). Nevertheless, the coating (429) is thermally conductive, and as a result, the thermal junctions (413, 416) are in thermal communication with the distal tip member (142). Specifically, the thermal junctions (413, 416) may be in thermal contact with the inner sidewall of the hole (162) without being in electrical communication with the inner sidewall of the hole (162), while maintaining thermal communication with the inner sidewall of the hole (162).

[0044] The flexible circuit (400) in this example further includes a lateral portion (418) of the substrate layer (417) that projects laterally relative to the adjacent portion of the substrate layer (417). The thermal junctions (413, 416) are positioned on the lateral portion (418) such that the distal portions of the traces (412, 415) reach the thermal junctions (413, 416). A third trace (421) also extends along the lateral portion (418). As shown in Figures 10A to 11, the lateral portion (418) is folded so that it is positioned below the adjacent region of the substrate layer (417). The folded lateral portion (418), like the partially compressed spacer layer (221) of the flexible circuit (200) and the folded distal portion (318) of the flexible circuit (300), acts as a spring, elastically biasing the thermocouple assembly (410) radially outward with respect to the longitudinal central axis (LL). This effect can minimize the distance between the thermal junctions (413, 416) and the outer surface of the cylindrical body (156), which can maximize the sensitivity of the thermal junctions (413, 416) to the temperature of the cylindrical body (156) and the tissue in contact with the cylindrical body (156). This can maximize the sensitivity of the joint (425) to the temperature of the cylindrical body (156) and the tissue in contact with the cylindrical body (156). Thus, the folded lateral portion (418) can promote thermal conductivity between the thermocouple assembly (410) and the cylindrical body (156).

[0045] Furthermore, the folded lateral portion (418) may tend to provide fixation of the thermocouple assembly (410) within the hole (162) by extending the effective cross-sectional profile of the thermocouple assembly (410). In some cases, the elastic bias of the folded lateral portion (418) biases the lateral portion (418) toward a flat / unfolded configuration, as a result, the lateral portion (418) abuts against the inner sidewall of the hole (162), thereby increasing the friction for fixing the thermocouple assembly (410) within the hole (162).

[0046] The positioning and securing of the thermocouple assembly (410) within the hole (162) may be further supplemented with an adhesive (427) that bonds the thermocouple assembly (410) to the distal tip member (142). In some cases where the adhesive is used, although not shown in these drawings, at least a portion of the adhesive may occupy the space formed between the folded lateral portion (418) and the underside of the third trace (421) and the substrate layer (417) (or the underside of an additional electrical insulating layer (not shown) located beneath the third trace (421)). As merely an example, such an adhesive may be provided by a thermoplastic polyurethane elastomer that is introduced into the hole (162) after the thermocouple assembly (410) has fully seated within the hole (162). As merely another example, such a thermoplastic polyurethane elastomer may be doped with diamond powder and cured with ultraviolet light. Alternatively, any other suitable type of adhesive may be used, and any other suitable process may be used to bond the thermocouple assembly (410) to the distal tip member (142).

[0047] VI. A fourth embodiment of a flexible circuit Figures 12-13 show a fourth embodiment of flexible circuit (500) which may be substantially identical in form and function to flexible circuits (200, 300, 400) except for any differences described below. Thus, flexible circuit (200) may be replaced by flexible circuit (500). Similar to flexible circuits (200, 300, 400), the flexible circuit (500) in this example includes a thermocouple assembly (510) comprising a conductive first trace (512), a conductive second trace (515), and a conductive third trace (521). The first trace (512) and the second trace (515) extend along the upper surface of an electrically insulating substrate layer (517). As an example, the substrate layer (517) may include polyimide and / or any other suitable material. The third trace (521) extends along the lower surface of the substrate layer (517). The traces (512, 515, 521) and substrate layer (517) extend along the length of the sheath (122).

[0048] The distal end of the first trace (512) includes a first thermal junction (513), while the distal end of the second trace (515) includes a second thermal junction (516). The first thermal junction (513) is electrically coupled to the third trace (521) via a joint (523). The second thermal junction (516) is electrically coupled to the third trace (521) via a similar joint (not shown). The joint (523) penetrates the entire thickness of the substrate layer (517). In this embodiment, each of the first trace (512) (including the first thermal junction (513)) and the second trace (515) (including the second thermal junction (516)) comprises a first conductive material (e.g., copper), while the third trace (521) comprises a second conductive material (e.g., constantan or a copper-nickel alloy). Due to the differences in conductive materials, the temperature change at the junction (523) provides temperature gradients between the first trace (512) and the third trace (521), and between the second trace (515) and the third trace (521), respectively. These temperature gradients can generate thermoelectric voltages. Thus, the thermocouple assembly (510) can provide temperature sensing in a similar manner to that described above with respect to the thermocouple assembly (210).

[0049] As shown in Figures 12A and 13, the electrical insulating coating (529) may be positioned over at least a portion of the thermal junctions (513, 516) and traces (512, 515). In some cases, the coating (529) may extend further along the length of the traces (512, 515). The coating (529) electrically insulates the traces (512, 515) and thermal junctions (513, 516) from the distal tip member (142). Nevertheless, the coating (529) is thermally conductive, and as a result, the thermal junctions (513, 516) are in thermal communication with the distal tip member (142). Specifically, the thermal junctions (513, 516) may be in thermal contact with the inner sidewall of the hole (162) without being in electrical communication with the inner sidewall of the hole (162), while maintaining thermal communication with the inner sidewall of the hole (162).

[0050] The thermal junctions (513, 516) are positioned on the distal portion (518) of the substrate layer (517) of the flexible circuit (500) in this example. As shown in Figure 12A, the distal portion (518) may be folded proximal before the thermocouple assembly (510) is inserted into the hole (162). The folded distal portion (518), like the partially compressed spacer layer (221) of the flexible circuit (200), acts as a spring, elastically biasing the thermocouple assembly (510) radially outward with respect to the longitudinal central axis (LL). This effect can minimize the distance between the thermal junctions (513, 516) and the outer surface of the cylindrical body (156), which can maximize the sensitivity of the thermal junctions (513, 516) to the temperature of the cylindrical body (156) and the tissue in contact with the cylindrical body (156). This maximizes the sensitivity of the joint (323, 325) to the temperature of the cylindrical body (156) and the tissue in contact with the cylindrical body (156). The folded distal portion (518)) can therefore facilitate thermal conductivity between the thermocouple assembly (510) and the cylindrical body (156).

[0051] Furthermore, the folded distal portion (518) may tend to provide fixation of the thermocouple assembly (510) within the hole (162) by extending the effective cross-sectional profile of the thermocouple assembly (510). In some cases, the elastic bias of the folded distal portion (518) biases the distal portion (518) toward a straight / unfolded configuration, as a result, the distal portion (518) abuts against the inner sidewall of the hole (162), thereby increasing the friction for fixing the thermocouple assembly (510) within the hole (162).

[0052] The positioning and securing of the thermocouple assembly (510) within the hole (162) may be further supplemented with an adhesive (527) that adheres the flexible circuit (500) to the distal tip member (142). In some cases where the adhesive is used, although not shown in these drawings, at least a portion of the adhesive may occupy the space formed between the folded distal portion (518) and the underside of the third trace (521) and the substrate layer (517) (or the underside of an additional electrical insulation layer (not shown) located beneath the third trace (521)). As merely an example, such an adhesive may be provided by a thermoplastic polyurethane elastomer that is introduced into the hole (162) after the thermocouple assembly (510) has fully seated within the hole (162). As merely another example, such a thermoplastic polyurethane elastomer may be doped with diamond powder and cured with ultraviolet light. Alternatively, any other suitable type of adhesive may be used, and any other suitable process may be used to bond the thermocouple assembly (510) to the distal tip member (142).

[0053] VII. Fifth Embodiment of a Flexible Circuit Figures 14-15 show a fifth embodiment of flexible circuit (600) which may be substantially identical in form and function to flexible circuits (200, 300, 400, 500) except for any differences described below. Thus, flexible circuit (200) may be replaced by flexible circuit (600). Similar to flexible circuit (200), flexible circuit (600) in this example includes a thermocouple assembly (610) comprising a conductive first trace (612), a conductive second trace (615), and a conductive third trace (621). The first trace (612) and the second trace (615) extend along the upper surface of an electrically insulating substrate layer (617). As an example, the substrate layer (617) may include polyimide and / or any other suitable material. The third trace (621) extends along the lower surface of the substrate layer (617). The traces (612, 615, 621) and substrate layer (617) extend along the length of the sheath (122).

[0054] The distal end of the first trace (612) includes a first thermal junction (613), while the distal end of the second trace (615) includes a second thermal junction (616). The first thermal junction (613) is electrically coupled to the third trace (621) via a joint (not shown). The second thermal junction (616) is electrically coupled to the third trace (621) via a joint (625). The joint (625) penetrates the entire thickness of the substrate layer (617). In this embodiment, each of the first trace (612) (including the first thermal junction (613)) and the second trace (615) (including the second thermal junction (616)) comprises a first conductive material (e.g., copper), while the third trace (621) comprises a second conductive material (e.g., constantan or a copper-nickel alloy). Due to the differences in conductive materials, temperature changes at the junction (625) provide temperature gradients between the first trace (612) and the third trace (621), and between the second trace (615) and the third trace (621), respectively. These temperature gradients can generate thermoelectric voltages. Thus, the thermocouple assembly (610) can provide temperature sensing in a similar manner to that described above with respect to the thermocouple assembly (210).

[0055] As shown in Figures 14A and 15, the electrical insulating coating (629) may be positioned over at least a portion of the thermal junctions (613, 616) and traces (612, 615). In some cases, the coating (629) extends further along the length of the traces (612, 615). The coating (629) electrically insulates the traces (612, 615) and thermal junctions (613, 616) from the distal tip member (142). Nevertheless, the coating (629) is thermally conductive, and as a result, the thermal junctions (613, 616) are in thermal communication with the distal tip member (142). Specifically, the thermal junctions (613, 616) can be in thermal contact with the inner sidewall of the hole (162) without being in electrical communication with the inner sidewall of the hole (162), while maintaining thermal communication with the inner sidewall of the hole (162).

[0056] The flexible circuit (600) in this example further includes a lateral portion (618) of the substrate layer (617) that projects laterally relative to the adjacent portion of the substrate layer (617). The thermal junctions (613, 616) are positioned on the adjacent portion of the substrate layer (617) such that the thermal junctions (613, 616) are outside the lateral portion (618) and the distal portions of the traces (612, 615) extend along the substrate layer (617) to reach the thermal junctions (613, 616). A third trace (621) extends along the lateral portion (618). As shown in Figures 14A to 15, the lateral portion (618) is folded so that it is positioned below the adjacent region of the substrate layer (617). The folded lateral portion (618), like the partially compressed spacer layer (221) of the flexible circuit (200), the folded distal portion (318) of the flexible circuit (300), and the folded lateral portion (418) of the flexible circuit (400), acts as a spring, elastically biasing the thermocouple assembly (610) radially outward with respect to the longitudinal central axis (LL). This effect can minimize the distance between the thermal junctions (613, 616) and the outer surface of the cylindrical body (156), which can maximize the sensitivity of the thermal junctions (613, 616) to the temperature of the cylindrical body (156) and the tissue in contact with the cylindrical body (156). This can maximize the sensitivity of the joint (625) to the temperature of the cylindrical body (156) and the tissue in contact with the cylindrical body (156). The folded lateral portion (618) can therefore facilitate thermal conductivity between the thermocouple assembly (610) and the cylindrical body (156).

[0057] Furthermore, the folded lateral portion (618) may tend to provide fixation of the thermocouple assembly (610) within the hole (162) by extending the effective cross-sectional profile of the thermocouple assembly (610). In some cases, the elastic bias of the folded lateral portion (618) biases the lateral portion (618) toward a flat / unfolded configuration, as a result the outer portion (618) abuts against the inner sidewall of the hole (162), thereby increasing the friction for fixing the thermocouple assembly (610) within the hole (162).

[0058] The positioning and securing of the thermocouple assembly (610) within the hole (162) may be further supplemented with an adhesive (627) that bonds the thermocouple assembly (610) to the distal tip member (142). In some cases where the adhesive is used, although not shown in these drawings, at least a portion of the adhesive may occupy the space formed between the folded lateral portion (618) and the underside of the third trace (621) and the substrate layer (617) (or the underside of an additional electrical insulating layer (not shown) located beneath the third trace (621)). As merely an example, such an adhesive may be provided by a thermoplastic polyurethane elastomer that is introduced into the hole (162) after the thermocouple assembly (610) has fully seated within the hole (162). As merely another example, such a thermoplastic polyurethane elastomer may be doped with diamond powder and cured with ultraviolet light. Alternatively, any other suitable type of adhesive may be used, and any other suitable process may be used to bond the thermocouple assembly (610) to the distal tip member (142).

[0059] VII. Examples of Combinations The following embodiments relate to various non-exclusive ways in which the teachings herein may be combined or applied. It should be understood that the following embodiments are not intended to limit any claims that may be presented at any point in this application or any subsequent application. No waiver of rights is intended. The following embodiments are provided solely for illustrative purposes. Various teachings herein are intended to be constructed and applied in many other ways. Furthermore, some modifications may omit certain features mentioned in the following embodiments. Therefore, none of the embodiments or features mentioned below should be considered important unless they are subsequently explicitly indicated as such by the inventors or their heirs. If claims presented in this application or any subsequent application relating to this application include additional features other than those mentioned below, those additional features should not be considered added for any patentability reason. [Examples]

[0060] (a) a shaft assembly having a distal end; (b) an end effector positioned at the distal end of the shaft assembly, the end effector including a tip member which is operable to apply electrical energy to tissue, the tip member defining a hole which has an inner side wall; and (c) a flexible circuit which includes a thermocouple positioned in the hole of the tip member which is configured to sense the temperature of the tip member, the flexible circuit further including a deformable feature which elastically biases the thermocouple toward the inner side wall of the hole. [Examples]

[0061] The apparatus according to Embodiment 1, wherein the flexible circuit further includes (i) a first trace extending to a thermocouple, (ii) a second trace extending to a thermocouple, and (iii) an insulating layer configured to electrically insulate the first and second traces from the end member. [Examples]

[0062] The apparatus according to any one of Examples 1 to 2, further comprising an adhesive, wherein the thermocouple is fixed to the inside of the hole in the tip member via the adhesive. [Examples]

[0063] The apparatus according to any one of Examples 1 to 3, wherein the deformable feature portion includes a deformable spacer layer. [Examples]

[0064] The apparatus according to any one of Examples 1 to 4, wherein the flexible circuit further includes a flexible substrate, and the deformable feature portion includes a distal portion of the flexible substrate, the distal portion being configured to extend distally with respect to the thermocouple, and the distal portion being bent proximally, thereby elastically biasing the thermocouple toward the inner side wall of the hole. [Examples]

[0065] The apparatus according to any one of Examples 1 to 5, wherein the flexible circuit further includes a flexible substrate, and the deformable feature portion includes a lateral portion of the flexible substrate, the lateral portion being configured to extend laterally with respect to the thermocouple, and the distal portion being bent inward, thereby elastically biasing the thermocouple toward the inner side wall of the hole. [Examples]

[0066] The flexible circuit further comprises (i) a first conductive feature portion containing a first type of conductive material, (ii) a second conductive feature portion containing a second type of conductive material, wherein the second type of conductive material is different from the first type of conductive material, (iii) an electrical insulating layer separating the first conductive feature portion from the second conductive feature portion, and (iv) a first junction portion electrically coupling the first conductive feature portion with the second conductive feature portion, according to any one of Examples 1 to 6. [Examples]

[0067] The apparatus according to Example 7, wherein the first type of conductive material comprises copper, and the second type of conductive material comprises constantan. [Examples]

[0068] The apparatus according to either Example 7 or 8, wherein the electrical insulating layer contains polyimide. [Examples]

[0069] The flexible circuit further comprises (i) a third conductive feature portion comprising a first type of conductive material, wherein an electrical insulating layer separates the third conductive feature portion from the second conductive feature portion; and (ii) a second junction portion electrically coupling the third conductive feature portion with the second conductive feature portion, according to any one of Examples 7 to 9. [Examples]

[0070] The apparatus according to any one of Examples 1 to 10, further comprising: (i) a distal portion in which a thermocouple is positioned along the distal portion; and (ii) a proximal portion in which an array of solder pads is included, the array of solder pads being electrically in communication with the thermocouple. [Examples]

[0071] The apparatus according to Embodiment 11, further comprising a printed circuit board including an array of contact pads, wherein each solder pad of the flexible circuit is electrically in communication with each contact pad of the array of contact pads. [Examples]

[0072] The apparatus according to any one of Examples 1 to 12, further comprising a handle, wherein the flexible circuit extends from the handle through the shaft assembly to the end effector. [Examples]

[0073] The apparatus according to any one of Examples 1 to 13, wherein the end effector is positioned between the tip member and the thermocouple, and further includes an insulating layer that electrically insulates the thermocouple from the tip member. [Examples]

[0074] The apparatus according to any one of Examples 1 to 14, wherein the catheter further comprises a plurality of thermocouples, the plurality of thermocouples comprising a flexible circuit, and the plurality of thermocouples being angularly spaced apart from one another within the tip member. [Examples]

[0075] An apparatus comprising: (a) a handle including a printed circuit board; (b) a shaft assembly extending distally from the handle and having a distal end; (c) an end effector positioned at the distal end of the shaft assembly; and (d) a flexible circuit extending along the shaft assembly, the flexible circuit having a thermocouple positioned within the end effector, the thermocouple being configured to sense the temperature of the end effector, the distal portion of the flexible circuit being deformable within the end effector, thereby elastically promoting thermal conductivity between the thermocouple and the end effector, and the flexible circuit being electrically in communication with the printed circuit board. [Examples]

[0076] The apparatus according to Example 16, wherein the distal portion includes one or more of a compressible spacer, a foldable distal projection, or a foldable lateral projection. [Examples]

[0077] A method for attaching a thermocouple assembly to the end effector of a catheter, wherein the thermocouple assembly is part of a flexible circuit, the flexible circuit includes a deformable member, the deformable member is configured to transition from a non-deformable state to a deformable state, the deformable member is elastically biased toward the non-deformable state, and the method comprises (a) deforming the deformable member of the flexible circuit to provide the deformable member in a deformed state; (b) positioning the thermocouple and the deformable member within a hole in the end effector while the deformable member is in a deformed state, such that the deformable member elastically biases the thermocouple toward the side wall of the hole; and (c) fixing the flexible circuit to the end effector while the thermocouple and the deformable member are within the hole in the end effector. [Examples]

[0078] The method according to Example 18, wherein the deformable member includes a spacer layer, and the act of deforming the deformable member includes compressing at least a portion of the spacer layer. [Examples]

[0079] The deformable member comprises a protruding portion of a flexible substrate, the protruding portion protruding distally or laterally relative to an adjacent area of ​​the flexible substrate, and the act of deforming the deformable member includes folding the protruding portion, according to any one of Examples 18 to 19.

[0080] VII. Others Any of the instruments described herein may be cleaned and sterilized before and / or after a procedure. One sterilization technique involves placing the device in a sealed container, such as a plastic or TYVEK bag. The container and device may then be placed in a radiation field that can penetrate the container, such as gamma rays, X-rays, or high-energy electron beams. The radiation may kill bacteria on the device and within the container. The sterilized device may then be stored in a sterile container for later use. The device may also be sterilized using any other technique known in the art, including, but not limited to, beta or gamma rays, ethylene oxide, hydrogen peroxide, peracetic acid, and gas-phase sterilization with or without gas plasma or steam.

[0081] It should be understood that any of the embodiments described herein may include a variety of other features in addition to or instead of those described above. For example, any of the embodiments described herein may include one or more of the various features disclosed in any of the various references incorporated herein by reference.

[0082] It should be understood that one or more of the teachings, expressions, embodiments, examples, etc. described herein may be combined with one or more of the other teachings, expressions, embodiments, examples, etc. described herein. Therefore, the above teachings, expressions, embodiments, examples, etc. should not be considered in isolation from each other. Various preferred ways in which the teachings herein may be combined will be readily apparent to those skilled in the art in view of the teachings herein. Such modifications and variations are intended to be included in the claims.

[0083] Any patents, publications, or other disclosures, in whole or in part, that are referred to as being incorporated herein by reference are incorporated herein only to the extent that the incorporated content does not conflict with the current definitions, views, or other disclosures contained herein. Any disclosure expressly contained herein, either in itself or to the extent necessary, takes precedence over any conflicting statements incorporated herein by reference. Any content, or any portion thereof, that is referred to as being incorporated herein by reference but conflicts with the current definitions, views, or other disclosures contained herein is incorporated only to the extent that it does not create a conflict between the incorporated content and the current disclosures.

[0084] While various modifications of the present invention have been illustrated and described, further adaptations of the methods and systems described herein can be achieved by appropriate modifications by those skilled in the art without departing from the scope of the invention. Some of these possible modifications have been mentioned, but others will be obvious to those skilled in the art. For example, the embodiments, modifications, geometric shapes, materials, dimensions, proportions, processes, etc., discussed above are illustrative and not essential. Therefore, it should be understood that the scope of the invention is to be considered with respect to the following claims and is not limited to the details of structures and operations shown and described herein and in the drawings.

[0085] [Implementation Method] (1) (a) A shaft assembly having a distal end, (b) An end effector positioned at the distal end of the shaft assembly, the end effector includes a tip member, the tip member is operable to apply electrical energy to tissue, the tip member defines a hole, the hole has an inner side wall, and the end effector (c) A flexible circuit comprising a flexible circuit, the flexible circuit including a thermocouple positioned in the hole of the tip member, the thermocouple being configured to sense the temperature of the tip member, the flexible circuit further comprising a deformable feature portion, the deformable feature portion elastically biasing the thermocouple toward the inner side wall of the hole, the flexible circuit. (2) The flexible circuit is (i) A first trace extending to the thermocouple, (ii) A second trace extending to the thermocouple, (iii) The apparatus according to Embodiment 1, further comprising an insulating layer configured to electrically insulate the first trace and the second trace from the tip member. (3) The apparatus according to Embodiment 1, further comprising an adhesive, wherein the thermocouple is fixed to the inside of the hole in the tip member via the adhesive. (4) The apparatus according to Embodiment 1, wherein the deformable feature portion includes a deformable spacer layer. (5) The apparatus according to Embodiment 1, wherein the flexible circuit further includes a flexible substrate, the deformable feature portion includes a distal portion of the flexible substrate, the distal portion is configured to extend distally with respect to the thermocouple, the distal portion is bent proximally, thereby elastically biasing the thermocouple toward the inner side wall of the hole.

[0086] (6) The apparatus according to Embodiment 1, wherein the flexible circuit further includes a flexible substrate, the deformable feature portion includes a lateral portion of the flexible substrate, the lateral portion is configured to extend laterally with respect to the thermocouple, and the distal portion is bent inward to elastically bias the thermocouple toward the inner side wall of the hole. (7) The flexible circuit is (i) A first conductive feature portion comprising a first type of conductive material, (ii) A second conductive feature portion comprising a second type of conductive material, wherein the second type of conductive material is different from the first type of conductive material, (iii) an electrical insulating layer that separates the first conductive feature portion from the second conductive feature portion, (iv) The apparatus according to Embodiment 1, further comprising a first junction that electrically couples the first conductive feature portion with the second conductive feature portion. (8) The apparatus according to Embodiment 7, wherein the first type of conductive material comprises copper and the second type of conductive material comprises constantan. (9) The apparatus according to Embodiment 7, wherein the electrical insulating layer includes polyimide. (10) The flexible circuit is (i) A third conductive feature portion comprising the first type of conductive material, wherein the electrical insulating layer separates the third conductive feature portion from the second conductive feature portion, (ii) The apparatus according to Embodiment 7, further comprising a second junction that electrically couples the third conductive feature portion with the second conductive feature portion.

[0087] (11) The flexible circuit is (i) A distal portion, the thermocouple being positioned along the distal portion, (ii) The apparatus according to Embodiment 1, further comprising a proximal portion including an array of solder pads, the array of solder pads being electrically in communication with the thermocouple. (12) The apparatus according to embodiment 11, further comprising a printed circuit board including an array of contact pads, wherein each solder pad of the flexible circuit is electrically in communication with each contact pad of the array of contact pads. (13) The apparatus according to Embodiment 1, further comprising a handle, wherein the flexible circuit extends from the handle through the shaft assembly to the end effector. (14) The apparatus according to Embodiment 1, wherein the end effector further includes an insulating layer positioned between the tip member and the thermocouple, thereby electrically insulating the thermocouple from the tip member. (15) The apparatus according to Embodiment 1, wherein the catheter further comprises a plurality of thermocouples, the plurality of thermocouples comprising the thermocouples of the flexible circuit, and the plurality of thermocouples being angularly spaced apart from one another within the tip member.

[0088] (16) (a) A handle including a printed circuit board, (b) A shaft assembly extending distally to the handle and having a distal end, (c) an end effector positioned at the distal end of the shaft assembly, (d) A device comprising a flexible circuit extending along the shaft assembly, the flexible circuit having a thermocouple positioned within the end effector, the thermocouple being configured to sense the temperature of the end effector, the distal portion of the flexible circuit being deformable within the end effector to elastically promote thermal conductivity between the thermocouple and the end effector, and the flexible circuit being electrically connected to the printed circuit board. (17) The apparatus according to embodiment 16, wherein the distal portion includes one or more of a compressible spacer, a foldable distal projection, or a foldable lateral projection. (18) A method for attaching a thermocouple assembly to the end effector of a catheter, wherein the thermocouple assembly is part of a flexible circuit, the flexible circuit includes a deformable member, the deformable member is configured to transition from a non-deformable state to a deformable state, the deformable member is elastically biased toward the non-deformable state, and the method is (a) To deform the deformable member of the flexible circuit and thereby provide the deformable member in the deformed state, (b) Positioning the thermocouple and the deformable member within the hole of the end effector while the deformable member is in the deformed state, wherein the deformable member elastically biases the thermocouple toward the side wall of the hole. (c) A method comprising fixing the flexible circuit to the end effector while the thermocouple and the deformable member are located in the hole of the end effector. (19) The method according to Embodiment 18, wherein the deformable member includes a spacer layer, and the act of deforming the deformable member includes compressing at least a portion of the spacer layer. (20) The method according to Embodiment 18, wherein the deformable member comprises a protruding portion of a flexible substrate, the protruding portion protruding distally or laterally to an adjacent area of ​​the flexible substrate, and the act of deforming the deformable member includes folding the protruding portion.

Claims

1. (a) A shaft assembly having a distal end, (b) An end effector positioned at the distal end of the shaft assembly, the end effector includes a tip member, the tip member is operable to apply electrical energy to tissue, the tip member defines a hole, the hole has an inner side wall, and (c) A flexible circuit comprising a flexible circuit, the flexible circuit including a thermocouple positioned in the hole of the tip member, the thermocouple configured to sense the temperature of the tip member, the flexible circuit further comprising a deformable feature portion, the deformable feature portion elastically biasing the thermocouple toward the inner side wall of the hole, the flexible circuit.

2. The aforementioned extension circuit is (i) A first trace extending to the thermocouple, (ii) A second trace extending to the thermocouple, (iii) The apparatus according to claim 1, further comprising an insulating layer configured to electrically insulate the first trace and the second trace from the tip member.

3. The apparatus according to claim 1, further comprising an adhesive, wherein the thermocouple is fixed to the inside of the hole in the tip member via the adhesive.

4. The apparatus according to claim 1, wherein the deformable feature portion includes a deformable spacer layer.

5. The apparatus according to claim 1, wherein the flexible circuit further includes a flexible substrate, the deformable feature includes a distal portion of the flexible substrate, the distal portion is configured to extend distally with respect to the thermocouple, the distal portion is bent proximally, thereby elastically biasing the thermocouple toward the inner side wall of the hole.

6. The apparatus according to claim 1, wherein the flexible circuit further includes a flexible substrate, the deformable feature includes a lateral portion of the flexible substrate, the lateral portion is configured to extend laterally with respect to the thermocouple, and the distal portion is bent inward to elastically bias the thermocouple toward the inner side wall of the hole.

7. The aforementioned extension circuit is (i) A first conductive feature portion comprising a first type of conductive material, (ii) A second conductive feature portion comprising a second type of conductive material, wherein the second type of conductive material is different from the first type of conductive material, (iii) an electrical insulating layer that separates the first conductive feature portion from the second conductive feature portion, (iv) The apparatus according to claim 1, further comprising: a first junction that electrically connects the first conductive feature portion to the second conductive feature portion.

8. The apparatus according to claim 7, wherein the first type of conductive material comprises copper, and the second type of conductive material comprises constantan.

9. The apparatus according to claim 7, wherein the electrical insulating layer comprises polyimide.

10. The aforementioned extension circuit is (i) A third conductive feature portion comprising the first type of conductive material, wherein the electrical insulating layer separates the third conductive feature portion from the second conductive feature portion, (ii) The apparatus according to claim 7, further comprising a second junction that electrically connects the third conductive feature portion to the second conductive feature portion.

11. The aforementioned extension circuit is (i) A distal portion, the thermocouple being positioned along the distal portion, (ii) The apparatus according to claim 1, further comprising a proximal portion including an array of solder pads, wherein the array of solder pads is electrically in communication with the thermocouple.

12. The apparatus according to claim 11, further comprising a printed circuit board including an array of contact pads, wherein each solder pad of the flexible circuit is electrically in communication with each contact pad of the array of contact pads.

13. The apparatus according to claim 1, further comprising a handle, wherein the flexible circuit extends from the handle through the shaft assembly to the end effector.

14. The apparatus according to claim 1, wherein the end effector further includes an insulating layer positioned between the tip member and the thermocouple, thereby electrically insulating the thermocouple from the tip member.

15. The apparatus according to claim 1, wherein the catheter further comprises a plurality of thermocouples, the plurality of thermocouples comprising the flexible circuit, and the plurality of thermocouples are angularly spaced apart from each other within the tip member.

16. (a) A handle including a printed circuit board, (b) A shaft assembly extending distally to the handle and having a distal end, (c) An end effector positioned at the distal end of the shaft assembly, (d) A device comprising a flexible circuit extending along the shaft assembly, the flexible circuit having a thermocouple positioned within the end effector, the thermocouple being configured to sense the temperature of the end effector, the distal portion of the flexible circuit being deformable within the end effector to elastically promote thermal conductivity between the thermocouple and the end effector, and the flexible circuit being electrically connected to the printed circuit board.

17. The apparatus according to claim 16, wherein the distal portion includes one or more of a compressible spacer, a foldable distal projection, or a foldable lateral projection.

18. A method for attaching a thermocouple assembly to the end effector of a catheter, wherein the thermocouple assembly is part of a flexible circuit, the flexible circuit includes a deformable member, the deformable member is configured to transition from a non-deformable state to a deformable state, the deformable member is elastically biased toward the non-deformable state, and the method is (a) to deform the deformable member of the flexible circuit and thereby provide the deformable member in the deformed state, (b) Positioning the thermocouple and the deformable member within the hole of the end effector while the deformable member is in the deformed state, wherein the deformable member elastically biases the thermocouple toward the side wall of the hole. (c) A method comprising fixing the flexible circuit to the end effector while the thermocouple and the deformable member are located in the hole of the end effector.

19. The method according to claim 18, wherein the deformable member includes a spacer layer, and the act of deforming the deformable member includes compressing at least a portion of the spacer layer.

20. The method according to claim 18, wherein the deformable member comprises a protruding portion of a flexible substrate, the protruding portion protrudes distally or laterally from an adjacent region of the flexible substrate, and the act of deforming the deformable member includes folding the protruding portion.

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