Methods and systems for an electrosurgical coagulation device

Abstract

Electrosurgical coagulation apparatus. At least some of the example embodiments are methods comprising: applying RF energy between a first electrode and a second electrode, the first electrode and the second electrode defining a gap; flowing a conductive fluid through a first nozzle of the first electrode and a second nozzle of the first electrode, the first nozzle defining a first jet direction, the second nozzle defining a second jet direction, and measuring a first angle between the first jet direction and the second jet direction through the gap to be 180 degrees or less; flowing the conductive fluid through a third nozzle of the second electrode and a fourth nozzle of the second electrode, the third nozzle defining a third jet direction, the fourth nozzle defining a fourth jet direction, and measuring a second angle between the third jet direction and the fourth jet direction through the gap to be 180 degrees or less.

Description

[0001] Cross-reference to related applications

[0002] This application is a conversion of U.S. Provisional Application No. 63 / 034,603, filed June 4, 2020, entitled "Methods and Systems of Electrocical Concution Devices". This application is also a conversion of U.S. Provisional Application No. 62 / 936,185, filed November 15, 2019, entitled "Bipolar Irrigating Electrosurgery". Both provisional applications are incorporated herein by reference as if reproduced in their entirety below. Background Technology

[0003] Coagulation devices, particularly those used in arthroplasty, involve delivering saline solution to the working tip of the device and to tissue at the target site. The saline solution is delivered to form a saline pool around the tip of the device at that site. The volume and distribution of the saline solution around the electrodes of the device, as well as the amount of saline solution delivered, influence the width, amplitude, and aggressiveness of the coagulation. Summary of the Invention

[0004] An exemplary embodiment is a method of operating an electrosurgical coagulation device, the method comprising: applying radio frequency (RF) energy between a first electrode and a second electrode, the first electrode defining a first longitudinal axis, the second electrode defining a second longitudinal axis coplanar with the first longitudinal axis, and the first electrode and the second electrode defining a gap; allowing conductive fluid to flow through a first nozzle and a second nozzle of the first electrode, the first nozzle defining a first jet direction, the second nozzle defining a second jet direction, and measuring a first angle between the first jet direction and the second jet direction through the gap as 180 degrees (°) or less; and allowing conductive fluid to flow through a third nozzle and a fourth nozzle of the second electrode, the third nozzle defining a third jet direction, the fourth nozzle defining a fourth jet direction, and measuring a second angle between the third jet direction and the fourth jet direction through the gap as 180 degrees (°) or less.

[0005] In the exemplary method: the first angle may be selected from at least one of the following: 170° or less; 120° or less; 90° or less; and 60° or less; and the second angle may be selected from at least one of the following: 170° or less; 120° or less; 90° or less; and 60° or less.

[0006] In the exemplary method, the first nozzle and the second nozzle may be mirror images of the positions of the third nozzle and the fourth nozzle across the gap, respectively.

[0007] In the exemplary method, the first injection direction, the second injection direction, the third injection direction, and the fourth injection direction may be in a common plane.

[0008] In an exemplary method: allowing the conductive fluid to flow through the first nozzle and the second nozzle may further include flowing at a first acute angle relative to the first longitudinal axis, the first acute angle opening toward the target tissue; allowing the conductive fluid to flow through the third nozzle and the fourth nozzle may further include flowing at a second acute angle relative to the second longitudinal axis, the third spray direction and the fourth spray direction opening toward the target tissue.

[0009] An exemplary method may further include: contacting the target tissue with the circular contact surface of the first electrode; and contacting the target tissue with the circular contact surface of the second electrode. The circular contact surface of the first electrode may be ellipsoidal, and the circular contact surface of the second electrode may also be ellipsoidal. Alternatively, the circular contact surface of the first electrode may be spherical, and the circular contact surface of the second electrode may also be spherical.

[0010] In an exemplary method, applying RF energy may further include: receiving an instruction for a flow rate setting from a plurality of flow rate settings at a controller for the electrosurgical coagulation device; receiving an instruction for an applied voltage setting at the controller; providing energy to the first and second electrodes within a voltage range determined by the applied voltage setting, the provided energy varying over time according to the impedance experienced between the first and second electrodes; pumping the conductive fluid through the first nozzle to the fourth nozzle, the flow rate being selected by the controller from a table associating the applied voltage setting and the flow rate setting, and the flow rate remaining constant over time as the provided energy varies.

[0011] In the exemplary method, the first longitudinal axis may be parallel to the second longitudinal axis.

[0012] Another exemplary embodiment is an electrosurgical device comprising: a handle having an irrigation cavity disposed therein; a cable coupled to a proximal end of the handle defining a first electrical conductor and a second electrical conductor; an elongated shaft coupled to the handle and defining a distal end opposite the handle; a first electrode disposed on the distal end of the elongated shaft and electrically coupled to the first electrical conductor, the first electrode defining a circular contact surface, a non-circular inner cross-section, and a first longitudinal axis opposite the distal end of the elongated shaft; and a second electrode disposed on the distal end of the elongated shaft and electrically coupled to the second electrical conductor. The system comprises: a circular contact surface opposite to the distal end of the elongated shaft; a non-circular inner cross-section; and a second longitudinal axis coplanar with the first longitudinal axis; a first nozzle defined by the first electrode, fluidly connected to the flushing cavity, the first nozzle defining a first spray direction between 0° and 90° relative to a line intersecting both the first and second longitudinal axes and including 0° and 90°; and a second nozzle defined by the second electrode, fluidly connected to the flushing cavity, the second nozzle defining a second spray direction between 0° and 90° relative to the line and including 0° and 90°.

[0013] An exemplary electrosurgical device may further include: a third nozzle defined by the first electrode, the third nozzle being fluidly coupled to the irrigation cavity, the third nozzle defining a third jet direction, the first jet direction and the third jet direction defining a first angle bisected by the line, and the first angle being equal to or less than 180°; and a fourth nozzle defined by the second electrode, the fourth nozzle being fluidly coupled to the irrigation cavity, the fourth nozzle defining a fourth jet direction, the second jet direction and the fourth jet direction defining a second angle bisected by the line, and the second angle being equal to or less than 180°. The first angle may be selected from at least one of the following: 170° or less; 120° or less; 90° or less; and 60° or less; and the second angle may be selected from at least one of the following: 170° or less; 120° or less; 90° or less; and 60° or less. The orientation of the first nozzle and the third nozzle may be mirror images of the positions of the second nozzle and the fourth nozzle across the gap between the first electrode and the second electrode, respectively.

[0014] In an exemplary electrosurgical device, the first jet direction, the second jet direction, the third jet direction, and the fourth jet direction may be in a common plane.

[0015] An exemplary electrosurgical device may further include: a first jet direction and a third jet direction that form a first acute angle relative to a first longitudinal axis, the first acute angle opening toward a circular contact surface of a first electrode; and a second jet direction and a fourth jet direction that form a second acute angle relative to a second longitudinal axis, the second acute angle opening toward a circular contact surface of a second electrode.

[0016] In an exemplary electrosurgical device, the circular contact surface of the first electrode may be elliptic, and the circular contact surface of the second electrode may be elliptic.

[0017] In an exemplary electrosurgical device, the circular contact surface of the first electrode may be spherical, and the circular contact surface of the second electrode may be spherical.

[0018] In an exemplary electrosurgical device, a first electrode may be rigidly coupled to an elongated shaft and is immovable relative to a second electrode, and a second electrode may be rigidly coupled to an elongated shaft and is immovable relative to the first electrode.

[0019] In an electrosurgical device, the line between the vertex of the circular contact surface of the first electrode and the vertex of the circular contact surface of the second electrode can be perpendicular to the first longitudinal axis of the first electrode.

[0020] In an exemplary electrosurgical device, the first electrode and the second electrode each have a polygonal cross-section. Alternatively, the first electrode and the second electrode may each have a square cross-section.

[0021] In an exemplary electrosurgical device, the first electrode and the second electrode may each have a square cross-section with chamfers.

[0022] In an exemplary electrosurgical device, the second longitudinal axis may be parallel to the first longitudinal axis.

[0023] Details of one or more embodiments of the present invention are set forth in the accompanying drawings and the following description. Other features, objects, and advantages of the invention will be apparent from the description, the drawings, and the claims. Attached Figure Description

[0024] For a detailed description of the exemplary embodiments, reference will now be made to the accompanying drawings, in which:

[0025] Figure 1 An electrosurgical coagulation system according to at least some embodiments is shown;

[0026] Figure 2 A perspective view of a rod 102 according to at least some embodiments is shown;

[0027] Figure 3AAn elevation view of the distal end of a device that comes into contact with tissue and is according to at least some embodiments is shown in block diagram form;

[0028] Figure 3B It shows basically along Figure 3A The line 3B-3B is cut off and is a cross-sectional view of the electrode according to at least some embodiments.

[0029] Figure 4A A front elevation view of the distal end of a device according to at least some embodiments is shown;

[0030] Figure 4B It shows basically along Figure 4A A cross-sectional view of the electrode taken by line 4B-4B;

[0031] Figure 4C A side elevation view of an electrode according to at least some embodiments is shown;

[0032] Figure 5A A front elevation view of the distal end of a device according to at least some embodiments is shown;

[0033] Figure 5B It shows basically along Figure 5A A cross-sectional view of the electrode taken from line 5B-5B and according to at least some embodiments;

[0034] Figures 6A-6B A front elevation view and a cross-sectional view of an electrode according to at least some embodiments are shown;

[0035] Figures 7A-7B A front elevation view and a cross-sectional view of an electrode according to at least some embodiments are shown;

[0036] Figure 8A A front elevation view of the distal end of a device according to at least some embodiments is shown;

[0037] Figure 8B It shows basically along Figure 8A The line 8B-8B is cut and is a cross-sectional view of the electrode according to at least some embodiments;

[0038] Figure 9A A front elevation view of the distal end of a device according to at least some embodiments is shown;

[0039] Figure 9B It shows basically along Figure 9A A cross-sectional view of the electrode taken from line 9B-9B and according to at least some embodiments;

[0040] Figure 10A A front elevation view of an electrode according to at least some embodiments is shown;

[0041] Figure 10B The illustration shows at least some embodiments Figure 10A A cross-sectional view of the electrode;

[0042] Figure 10C A cross-sectional view of an electrode is shown, wherein the injection direction forms an acute angle with the longitudinal central axis of the electrode and according to at least some embodiments;

[0043] Figure 10D It shows basically along Figure 10C A 10D-10D cut-off line and a cross-sectional view of the electrode according to at least some embodiments;

[0044] Figure 11A A side elevation view of an electrode according to at least some embodiments is shown;

[0045] Figure 11B A front elevation cross-sectional view of an electrode according to an exemplary embodiment is shown;

[0046] Figure 12 A partial cross-sectional view of a device according to at least some embodiments is shown;

[0047] Figure 13 A side elevation view of an electrode according to at least some embodiments is shown;

[0048] Figure 14 A perspective view of the distal end of a device according to at least some embodiments is shown;

[0049] Figure 15 A simplified cross-sectional view of a conductive tube, a fluid delivery tube, and an electrode according to at least some embodiments is shown;

[0050] Figure 16 A simplified cross-sectional view of a portion of a fluid delivery tube according to at least some embodiments is shown;

[0051] Figure 17 A perspective view of the distal end of a device according to at least some embodiments is shown;

[0052] Figure 19 A perspective view of an apparatus according to at least some embodiments is shown;

[0053] Figure 20 A graph showing the applied voltage versus pump speed according to at least some embodiments is shown; and

[0054] Figure 21 An exemplary coagulation controller according to at least some embodiments is shown in block diagram form.

[0055] definition

[0056] Various terms are used to refer to specific system components. Different companies may use different names to refer to a component—this document is not intended to distinguish between components with different names but the same function. In the following discussion and claims, the terms "comprising" and "including" are used in an open-ended manner and should therefore be interpreted as "including but not limited to...". Furthermore, the terms "connected" or "coupled" are intended to indicate indirect or direct connection. Thus, if a first device is connected to a second device, the connection can be either a direct connection or an indirect connection via other devices and connections.

[0057] "Elliptic" should be understood as a surface that defines three principal axes that intersect with the center of symmetry. A "spherical" surface is a subset of an ellipsoid in which the three principal axes are of equal length.

[0058] The "jet direction" of the nozzle should refer to the initial direction in which the brine column moves as the fluid leaves the nozzle. The "jet direction" should not be interpreted as requiring the fluid to be broken into droplets or atomized by the nozzle. Detailed Implementation

[0059] The following discussion relates to various embodiments of the invention. While one or more of these embodiments may be preferred, the disclosed embodiments should not be construed as or otherwise used to limit the scope of this disclosure, including the claims. Furthermore, those skilled in the art will understand that the following description has broad application, and the discussion of any embodiment is intended only as an example of that embodiment and is not intended to imply that the scope of this disclosure, including the claims, is limited to that embodiment.

[0060] Various exemplary embodiments relate to methods and systems for electrosurgical coagulation devices. Specifically, exemplary embodiments relate to electrosurgical coagulation devices having a first electrode and a second electrode disposed at the distal end of an elongated shaft coupled to a handle. The electrodes are arranged to define a gap between them, and radio frequency (RF) energy is applied across the electrodes in a bipolar manner to achieve coagulation. A conductive fluid emerges from nozzles in the electrodes, and in some cases, the conductive fluid provides controlled wetting of the target tissue and controlled dispersion of the conductive fluid from each electrode in a jet direction toward the other electrode. This specification first turns to the electrosurgical coagulation system to guide the reader.

[0061] Figure 1An electrosurgical coagulation system according to at least some embodiments is illustrated. Specifically, the electrosurgical coagulation system 100 includes an electrosurgical coagulation device 104 (hereinafter simply "device 104"), which includes an elongated shaft 106 defining a distal end 108. Furthermore, the device 104 includes a grip or handle 110 for a clinician to hold the device 104 during surgical procedures. The device 104 further includes a flexible multi-conductor cable 112 that houses one or more electrical conductors or leads (not specifically shown), and the flexible multi-conductor cable 112 terminates in a rod connector 114. Figure 1 As shown, device 104 is connected to coagulation controller 116, as through the outer surface of housing 120 (in Figure 1 In an exemplary case, the controller connector 118 is located on the front surface of the housing 120.

[0062] Despite Figure 1 While not visible in the view, in some embodiments, device 104 has an internal flow channel or fluid flushing chamber. The fluid flushing chamber of device 104 is coupled to a flexible tubular member 122 for supplying saline solution to the distal end 108 of device 104. According to an exemplary embodiment, the flexible tubular member 122 is coupled to a peristaltic pump 124, which is exemplary as a component integrated with the coagulation controller 116 (i.e., at least partially located within the housing 120 of the coagulation controller 116). In other embodiments, the housing of the peristaltic pump 124 may be separate from the housing 120 of the coagulation controller 116 (as shown by the dashed lines in the figures).

[0063] An exemplary peristaltic pump 124 includes a rotor portion 126 (hereinafter referred to as "rotor 126") and a stator portion 128 (hereinafter referred to as "stator 128"). A flexible tubular member 122 is coupled within the peristaltic pump 124 between the rotor 126 and the stator 128, and movement of the rotor 126 against the flexible tubular member 122 causes fluid movement from the suction port 130 toward the distal end 108 of the rod 102. Although an exemplary peristaltic pump 124 with a dual-head rotor 126 is shown, other types of peristaltic pumps 124 (e.g., a five-head peristaltic pump) can be used. In the context of the various embodiments, the peristaltic pump 124 generates a volume-controlled flow of a conductive fluid (e.g., saline, Ringer's solution) to a surgical field (not specifically shown) at the distal end 108 of the rod 104. Hereinafter, "conductive fluid" will be referred to as saline, but it is understood that any suitable conductive fluid can be used. The flow rate of the saline is based on the speed of the rotor 126 as commanded by the coagulation controller 116. The suction port 130 can be connected to any suitable brine source, such as in a hanging bag or other container. In other cases, any pump system that provides volume-controlled flow upon activation (e.g., a centrifugal pump with speed control) can be used.

[0064] Still referencing Figure 1 The display device or interface device 132 is visible through the housing 120 of the coagulation controller 116, and in some embodiments, the user can select the operating mode of the coagulation controller 116 via the interface device 132 and associated buttons 134. For example, using one or more of the buttons 134, a clinician can select the saline flow rate. As another example, using one or more of the buttons 134, a clinician can select an applied voltage setting to control the activating effect of coagulation.

[0065] In some embodiments, the electrosurgical coagulation system 100 also includes a foot pedal assembly 136. The foot pedal assembly 136 may include one or more foot pedal devices 138 and 140, a flexible multi-conductor cable 142, and a foot pedal connector 144. Although only two foot pedal devices 138 and 140 are shown, one or more foot pedal devices may be implemented. The housing 120 of the coagulation controller 116 may include a corresponding connector 146 coupled to the foot pedal connector 144. Clinicians can use the foot pedal assembly 136 to control various aspects of the coagulation controller 116. For example, foot pedal device 138 may be used for on / off control of RF energy applied to the distal end 108 of device 104. Furthermore, foot pedal device 140 may be used to control and / or set the flow of saline to the distal end 108 of device 104. Alternatively, various operational or performance aspects of the coagulation controller 116 (e.g., applied voltage setting) may be activated by selectively pressing an electrical switch or button 148 located on the handle 110 of rod 102.

[0066] Figure 2 A perspective view of a device 104 according to at least some embodiments is shown. Specifically, in Figure 2 The visible parts are the handle 110, the slender shaft 106, and the distal end 108. Figure 2 Also visible are buttons 148 that clinicians can use to control various aspects of the operation of device 104 (e.g., on-off control, applied voltage setting, saline flow rate). Specifically, button 150 controls the on-off state of coagulation, while button 152 controls the increase in coagulation function. The coagulation controller 116 is connected via a flexible multi-conductor cable 112. Figure 1 Energy is delivered to device 104, and brine is delivered through flexible tubular member 122. Figure 2More visible are the electrodes at the distal end 108 of the elongated shaft 106, namely electrodes 200 and 202. Each electrode is a metallic structure defining a proximal end coupled to the elongated shaft 106 and a relatively distal end that approaches or contacts tissue at the target site during operation in an electrosurgical coagulation procedure. As further discussed below, each electrode 200 and 202 defines an internal flushing fluid path or flow cavity operatively associated with one or more orifices or nozzles. Each nozzle defines a jet direction, and saline solution passes through the nozzle and exits each electrode in a nozzle-controlled direction. In an exemplary embodiment, the nozzles are arranged on the electrodes such that fluid exits each electrode in a direction toward the other electrode.

[0067] Reconsidering button 148, exemplary device 104 provides a temporarily increased coagulation output to handle unexpected blood volume in the surgical field. Button 148 on handle 110 includes an activation button 150 and a button 152, which may be referred to as the "MAX button," and actuation of button 152 results in increased coagulation (e.g., increased energy), but is not necessarily interpreted as requiring application of coagulation controller 116 ( Figure 1 The device 104 provides the maximum energy it can deliver. When the MAX button 152 is pressed, the device 104 provides a temporary, higher coagulation output to quickly resolve issues such as bleeding through a large blood vessel. As shown, the larger, more distal button 150 may be the activation button, and the smaller, lower-profile button spaced proximal to the button 150 is the MAX button 152.

[0068] In other cases, instead of using two buttons 150 and 152, a single button can be used to provide both the selected therapeutic output and the amplified output. For example, the single button can be activated in one way to provide the therapeutic output and in a different way to provide the amplified output, such as by pressing the button into the handle for the therapeutic output, while moving the button distally to activate the amplified output. Alternatively, a joystick button can be used. By making the action required to activate the amplified output more conscious, accidental activation of the amplified output can be reduced. For example, the user may have to press down with greater force to activate the amplified output, and / or the button's position may be spaced apart from the natural position of the clinician's fingers, and / or the button's size may be smaller, requiring the user to actively locate the button.

[0069] Figure 3A A simplified block diagram shows an elevation view of the distal end of the device 104, which contacts the tissue at the target site and is according to at least some embodiments. Specifically, Figure 3AVisible are a portion of the elongated shaft 106, electrodes 200 and 202, and a portion of the tissue 300 at the target site. In an exemplary embodiment, electrodes 200 and 202 are rigidly coupled to the elongated shaft 106 at their proximal ends. Therefore, in some cases, electrodes 200 and 202 are immovable relative to each other and to the elongated shaft 106. In an exemplary embodiment, electrodes 200 and 202 are spaced apart from each other, thus forming a region or gap space between the electrodes, referred to as gap 304. Each electrode 200 and 202 defines an exposure length L measured from the distal end of the elongated shaft 106 to the distal end of each electrode, and in the exemplary case, the length L of each electrode is the same. As will be discussed in more detail below, in some cases, the distal end of each electrode is rounded, and the length L is measured to the bottommost point of each electrode (if the electrode points downward relative to gravity). That is, in the case where the distal end of each electrode is rounded, the length L is measured to the apex of each electrode (if the electrode points upward relative to gravity).

[0070] Still referencing Figure 3A For efficient operation, brine is delivered into a concise volume 302 surrounding electrodes 200 and 202, included within gap 304. Specifically, fluid delivery is achieved via nozzles on each electrode 200 and 202. Figure 3A (Not shown in the diagram) The nozzles are arranged such that the jet direction of each nozzle delivers saline between the electrodes and also flows to fill the simple volume 302 surrounding electrodes 200 and 202. Delivering saline in this manner improves coagulation properties at the target site and reduces the total amount of saline used during the procedure.

[0071] In addition to the jet direction of each nozzle (discussed in more detail below), electrodes 200 and 202 are designed and configured to enhance wetting within the compact volume 302, and particularly the wetting of electrodes 200 and 202. For this purpose, electrodes 200 and 202 may have features on their outer surfaces to guide the flow of brine. One exemplary feature includes a hydrophobic or hydrophilic surface treatment and / or coating on electrodes 200 and 202. Another exemplary feature is that the fluid outlet geometry (e.g., the jet direction of each nozzle) may be designed to more effectively disperse fluid across gap 304 around electrodes 200 and 202 and fill the compact volume 302.

[0072] Improved wetting of electrodes 200 and 202 reduces tissue charring at the target site, reduces the accumulation of charred tissue on electrodes 200 and 202, and improves the maneuverability of the device across the tissue 300 at the target site. In some cases, the distal surfaces of electrodes 200 and 202 are designed to reduce contact with tissue to enhance the maneuverability of the device 104 across the target tissue. In some embodiments, planar surfaces on the sides of the electrodes increase the distance between nozzles on one electrode and nozzles on another electrode, reducing current bridging between electrodes via saline solution.

[0073] Figure 3B It shows basically along Figure 3A The cross-sectional view of the electrode is taken from line 3B-3B and according to at least some embodiments. Specifically, Figure 3B Visible are electrodes 200 and 202, and tissue 300 at the target site. As before, electrodes 200 and 202 define a gap 304. For the exemplary electrodes 200 and 202, the gap 304 is defined by the inward-facing parallel walls and chamfers of electrodes 200 and 202. However, and as will become clearer below, the gap 304 may be defined by portions of each electrode 200 and 202 that span the gap between the electrodes and face each other, even if those surfaces are not parallel. More precisely, the gap 304 may be a region or volume between electrodes 200 and 202, defined by the projection of one electrode onto the opposite electrode. Figure 3B In the exemplary arrangement, gap 304 is defined by outward coplanar walls on each side of the electrode, as shown by dashed lines 306 and 308. Therefore, for example, example point 312 on the simplified volume 302 would be considered not to be located within gap 304.

[0074] Figure 4A A front elevation view of the distal end of a device according to at least some embodiments is shown. Specifically, in Figure 4A What is visible is a portion of the elongated shaft 106, exemplary electrode 200, and exemplary electrode 202. As before, exemplary electrodes 200 and 202 are spaced apart from each other, thus forming a gap 304. Each electrode 200 and 202 defines an exposure length L measured from the distal end of the elongated shaft 106 to the distal end of each electrode, and in the exemplary case, the length L of each electrode is the same. Exemplary electrodes 200 and 202 each have a circular distal end or contact surface 410 and 412 (e.g., for contacting tissue at a target site during a coagulation procedure). In some cases, each circular contact surface may be ellipsoidal, and in certain cases, the contact surface may be spherical. In any case, the shape of the contact surface strikes a balance between reducing the contact area between each electrode 200 and 202 and the tissue at the target site and reducing the force required to move the electrode along the tissue at the target site during use.

[0075] Exemplary electrodes 200 and 202 each define a longitudinal central axis. Specifically, electrode 200 defines a longitudinal central axis 400. Similarly, electrode 202 defines a longitudinal central axis 402. In the exemplary arrangement, longitudinal central axes 400 and 402 are coplanar. In the specific case shown, longitudinal central axes 400 and 402 are parallel. However, in other cases, longitudinal central axes 400 and 402 may be coplanar but not parallel. For example, the electrodes may be outwardly extended or opened outward relative to the elongated axis 106, which increases the volume of gap 304. In still other cases, the electrodes may be tilted inward relative to the elongated axis 106, which decreases the volume of gap 304. Each of the extended and tilted arrangements may have operational advantages, but these advantages may differ.

[0076] Figure 4A The nozzles on each electrode are also visible. Specifically, in Figure 4A Visible are orifices or nozzles 404 exposed on the outer surface of electrode 200 and orifices or nozzles 406 exposed on the outer surface of electrode 202. Exemplary nozzle 404 is eccentric relative to electrode 200, and specifically, the outer wall of nozzle 404 is aligned with the longitudinal central axis 400, such that nozzle 404 is closer to gap 304. In other words, nozzle 404 is on the gap side of the longitudinal central axis 400. Similarly, exemplary nozzle 406 is eccentric relative to electrode 202, and specifically, the outer wall of nozzle 406 is aligned with the longitudinal central axis 402, such that nozzle 406 is closer to gap 304. In other words, nozzle 406 is on the gap side of the longitudinal central axis 402. Exemplary nozzle 404 is fluidly coupled to a flow cavity (not visible) within electrode 200, which is fluidly coupled to a flushing cavity within handle 110. Figure 1 The flushing cavity is fluidly connected to the peristaltic pump 124. Figure 1 The electrode 200 is supplied with a brine source and a saline solution. Therefore, during use, the brine flows out from within the electrode 200 through nozzle 404. Similarly, an exemplary nozzle 406 is fluidly connected to a flow cavity (not visible) within the electrode 202, which is fluidly connected to a flushing cavity within the handle 110. Figure 1 The flushing cavity is fluidly connected to the peristaltic pump 124. Figure 1 The brine source is provided. Therefore, during use, the brine flows out from the electrode 202 through the nozzle 404.

[0077] Figure 4B It shows basically along Figure 4A The cross-sectional view of the electrode is taken from line 4B-4B and according to at least some embodiments. Specifically, Figure 4B The view is an inside cross-sectional view, and... Figure 4B Electrode 200 and electrode 202 are visible. As before, electrodes 200 and 202 define a gap 304. Figure 4B To better illustrate, each exemplary electrode is a polygon, and specifically, each electrode is a square with chamfers (e.g., chamfer 414). Figure 4B In the exemplary case, electrodes 200 and 202 are arranged around their respective longitudinal central axes such that the inward-facing wall 416 of electrode 200 is parallel to the inward-facing wall 418 of electrode 202, but other arrangements are possible.

[0078] Figure 4B Examples of internal flow paths or flow cavities within each electrode can also be seen. Referring first to electrode 200, the flow cavity within electrode 200 includes a blind orifice 420 coaxial with the longitudinal central axis 400. The blind orifice 420 is referred to as "blind" in such a way that the orifice is formed in a manner that allows it to be fluidly connected at the proximal end of the electrode (e.g., to a flushing cavity within the handle 110). Figure 1 The hole 420 is opened at the contact surface 410, but the blind hole does not travel continuously through the electrode 200 (i.e., the hole does not create an opening through the contact surface 410). Furthermore, although called a hole, the blind hole 420 can be created using any suitable method (e.g., drilling, laser drilling, casting, and grinding). At the elevation of the nozzle, the exemplary flow cavity within the electrode 200 also includes a through-hole 422. Thus, the exemplary through-hole 422 defines the nozzle 404, and the nozzle 424 on the opposite side of the through-hole 422. The through-hole 422 can be created by any suitable method (e.g., drilling, laser drilling, casting, and grinding). In operation, brine flows through the flushing cavity of the handle 110 (…). Figure 1 ), along the flow cavity within the slender shaft 106 ( Figure 4A The brine flow then flows through the blind hole 420. The brine flow then splits into two streams at the intersection of the blind hole 420 and the through hole 422, and each stream exits the electrode 200 through a corresponding nozzle 404 or 424.

[0079] An exemplary through-hole 422 defines a central axis 426. The spray direction of nozzle 404 is coaxial with the central axis 426. Similarly, the spray direction of nozzle 424 is coaxial with the central axis 426, but... Figure 4B In this exemplary case, the spray direction of nozzle 424 is opposite to that of nozzle 404. In other words, the angle between the spray direction of nozzle 404 and the spray direction of nozzle 424 is 180 degrees (°) measured through gap 304, as indicated by double-headed arrow 427.

[0080] Referring now to electrode 202, the flow cavity within the electrode includes a blind orifice 428 coaxial with the longitudinal central axis 402. For the same reasons discussed with reference electrode 200, the blind orifice 428 is referred to as "blind" and can be produced using any suitable method. At the elevation of the nozzle, the exemplary flow cavity within electrode 202 also includes a through-hole 430. Thus, the exemplary through-hole 430 defines a nozzle 406, and a nozzle 432 on the opposite side of the through-hole 430. The through-hole 422 can also be produced in any suitable manner. In operation, brine flows through the fluid flushing cavity of the handle 110 (…). Figure 1 ), along the flow cavity within the slender shaft 106 ( Figure 4A The brine flow then flows through the blind hole 428. The brine flow then splits into two streams at the intersection of the blind hole 428 and the through hole 430, and each stream exits the electrode 202 through a corresponding nozzle 406 or 432.

[0081] The exemplary through-hole 430 also defines a central axis 434. The spray direction of nozzle 406 is coaxial with the central axis 434. Similarly, the spray direction of nozzle 432 is coaxial with the central axis 434, but... Figure 4B In the exemplary case, the spray direction of nozzle 432 is opposite to that of nozzle 404. In other words, the angle between the spray direction of nozzle 406 and the spray direction of nozzle 432 is 180°, measured via gap 304. Therefore, in Figure 4B In the exemplary case, the positions of nozzles 406 and 432 are mirror images of the positions of nozzles 404 and 424 across gap 304, respectively.

[0082] Figure 4B The relationship between the nozzles is merely one example, and the angle between the nozzles of the electrode can take many suitable forms. For example, and taking the reference electrode 200 as representative, in other cases, the through-hole 422 can be implemented as two separate holes that enter the electrode at an angle but still intersect with the blind hole 420. When implemented in this way, the angle between nozzle 404 and nozzle 424 can be less than 180°, in some cases 170° or less, in others 120° or less, in still others 90° or less, and in yet another instance 60° or less. More geometrically, each hole can have a central axis, and the angle between the central axis of the first hole and the central axis of the second hole can be less than 180°, including any angle less than 180° given in this paragraph.

[0083] Still referencing Figure 4BThe angle relative to the nozzle can be equivalently expressed as the angle between the nozzle's spray direction and an imaginary line intersecting the longitudinal central axis of the same electrode. For example, consider line 436 intersecting both longitudinal central axes 400 and 402. When considered in this way, the angle between nozzle 404, as a representative example, and line 436 can be less than 90°, in some cases 85° or less, in others 60° or less, in still others 45° or less, and in yet another instance 30° or less. In a particular case of a single nozzle implemented on each electrode, the angle can be 0°. The explanation of nozzle 404 also applies to nozzles 406, 424, and 432.

[0084] Also refer to Figure 4A and 4B For the exemplary electrode shown, the spray directions of nozzles 404, 424, 406, and 432 are all located in a common plane. When the longitudinal central axes 400 and 402 are parallel, the common plane is also perpendicular to the longitudinal central axes 400 and 402. However, in other cases, the spray directions of each nozzle do not need to be coplanar.

[0085] Figure 4C A side elevation view of an electrode according to at least some embodiments is shown. Specifically, Figure 4C A view of electrode 200 as viewed toward electrode 202 is shown, but electrode 202 is not visible. Figure 4C The diagram also shows the longitudinal central axis 400 and central axis 426 of electrode 200 in an exemplary case where the spray directions are coplanar. However, in other embodiments, the spray directions are not necessarily coplanar and may actually be angled toward the distal end of the electrode. Figure 4C Lines 438 and 440, representing the alternative injection directions of nozzles 404 and 424, are shown respectively. Figure 4A and 4B That is, lines 438 and 440 represent the central axis of the orifice defining the internal flow cavity and the corresponding nozzle of the electrode. In an exemplary case, each injection direction represented by lines 438 and 440 forms an acute angle with respect to the longitudinal central axis 400, as indicated by the double-headed arrow 442, the acute angle opening toward the circular contact surface of the electrode 200. In some cases, and as shown, the angles are the same, but in other cases, the angles may be different. Although the electrode 202 is in Figure 4C Although not visible in the image, the spray angle associated with the nozzle of electrode 202 can form a similar acute angle relative to the longitudinal central axis 402 of electrode 202.

[0086] Figure 5A A front elevation view of the distal end of a device according to at least some embodiments is shown. Specifically, Figure 5AExemplary electrodes 500 and 502 are visible. As before, exemplary electrodes 500 and 502 are spaced apart from each other, thus forming a gap 504. Electrodes 500 and 502 each have a circular distal end or contact surface, which may be ellipsoidal or spherical. Exemplary electrodes 500 and 502 define longitudinal central axes 506 and 508, respectively. In the exemplary arrangement, longitudinal central axes 506 and 508 are coplanar and parallel. However, in other cases, longitudinal central axes 506 and 508 may be coplanar but not parallel.

[0087] Figure 5A The nozzles on each electrode are also shown. Specifically, in Figure 5A Visible are orifices or nozzles 510 exposed on the outer surface of electrode 500, and orifices or nozzles 512 exposed on the outer surface of electrode 502. An exemplary nozzle 510 is fluidly connected to a flow cavity within electrode 200, which is fluidly connected to a flushing cavity within handle 110. Figure 1 The flushing cavity is fluidly connected to the peristaltic pump 124. Figure 1 The electrode 500 is supplied with a brine source and a saline solution. Therefore, during use, brine flows out from the electrode 500 through nozzle 510. Similarly, an exemplary nozzle 512 is fluidly connected to a flow cavity within the electrode 202, which is fluidly connected to a flushing cavity within the handle 110. Figure 1 The flushing cavity is fluidly connected to the peristaltic pump 124. Figure 1 The brine source is provided. Therefore, during use, brine flows out from inside electrode 502 through nozzle 512.

[0088] Figure 5B It shows basically along Figure 5A The line 5B-5B is cut and is a cross-sectional view of the electrode according to at least some embodiments. Specifically, in Figure 5B Electrodes 500 and 502 are visible. As before, electrodes 500 and 502 define a gap 504. Figure 5B To better illustrate, each exemplary electrode is a polygon, and specifically, each electrode is a square with chamfers (e.g., chamfer 514). Figure 5B In an exemplary configuration, electrodes 500 and 502 are arranged about their respective longitudinal central axes such that the inward-facing chamfer 514 of electrode 500 and the inward-facing chamfer 516 of electrode 502 are bisected by a line 519 extending between longitudinal central axes 506 and 508. That is, the flat sidewall 540 of electrode 500 lies in one plane, the flat sidewall 542 lies in another plane, and the two planes are perpendicular.

[0089] Figure 5BExamples of internal flow paths or flow cavities within each electrode are also visible. For example, electrode 500 defines a blind hole 518 coaxial with a longitudinal central axis 506. The blind hole 518 can be produced using any suitable method (e.g., drilling, laser drilling, casting, and grinding). At the elevation of the nozzle, exemplary flow cavities within electrode 500 also include orifices 520 and 522. Exemplary orifice 520 defines nozzle 510, and exemplary orifice 522 defines nozzle 524. Orifices 520 and 522 can be produced using any suitable method (e.g., drilling, laser drilling, casting, and grinding). In operation, brine flows through the flushing cavity of the handle 110 ( Figure 1 The brine flows along the flow cavity within the elongated shaft 106 and then through the blind orifice 518. The brine flow then splits into two streams at the intersection of the blind orifice 518 and the orifices 520 and 522, and each stream exits the electrode 500 through a corresponding nozzle 510 or 524.

[0090] Exemplary orifice 520 defines a central axis 526, and the jetting direction of nozzle 510 is coaxial with central axis 526. Exemplary orifice 522 defines a central axis 528, and the jetting direction of nozzle 524 is coaxial with central axis 528. Measured by gap 504, the angle between the jetting direction of nozzle 510 and the jetting direction of nozzle 524 is 90° or less, and in some cases 60° or less. Exemplary electrode 502 has a mirror image group of components including a blind orifice, an orifice intersecting the blind orifice, and a nozzle having a jetting direction. The individual components of the mirror image group are not specifically numbered or discussed to avoid excessively lengthy specification.

[0091] Still referencing Figure 5B The angle relative to the nozzle can be equivalently expressed as the angle between the nozzle's spray direction and line 519, which intersects the longitudinal central axis of the same electrode. When considered in this way, the angle between the spray direction of nozzle 510 and line 519 can be less than 45°, and in some cases 22.5° or less. In a particular case of a single nozzle implemented on each electrode, the angle can be 0° relative to line 519 (e.g., the spray direction can be coaxial with line 519). The same explanation applies to nozzles 512, 524, and 530. The spray directions of nozzles 510 and 512 can all lie in a common plane, or in other cases form an acute angle relative to the longitudinal central axis 506, opening toward the circular contact surface. The spray directions of nozzles 512 and 530 can all lie in a common plane, or in other cases form an acute angle relative to the longitudinal central axis 508, opening toward the circular contact surface.

[0092] Figures 6A-6BA front elevation view and a cross-sectional view of an electrode according to at least some embodiments are shown. Specifically, portion 600 is a front elevation view of the electrode, and portion 602 shows a cross-sectional view of portion 600 through a nozzle of the electrode. Figures 6A-6B Many components and relationships of the electrodes are referenced above. Figures 4A-4C The same points are discussed in 5A-5B, and will not be repeated here to avoid unnecessarily lengthening the instruction manual. However, Figures 6A-6B This demonstrates that when the chamfers span the gap and face each other, the nozzle's spray direction is not necessarily perpendicular to the surface of the electrode within which the nozzle is defined. Figures 6A-6B In an exemplary case, the angle between the spray directions (measured by the gap) of the nozzles of the electrodes can be 120° or less. Again, as shown in the figure, all spray directions are coplanar.

[0093] Figures 7A-7B A front elevation view and a cross-sectional view of an electrode according to at least some embodiments are shown. Specifically, portion 700 is a front elevation view of the electrode, and portion 702 shows a cross-sectional view of portion 700 through a nozzle of the electrode. Figures 7A-7B Many components and relationships of the electrodes are referenced above. Figures 4A-4C The same points are discussed in 5A-5B, and will not be repeated here to avoid unnecessarily lengthening the instruction manual. However, Figures 7A-7B An exemplary case is clearly shown where the nozzle's spray direction is angled downwards toward the circular contact surface. In other words, Figures 7A-7B An exemplary case is shown in which the spray direction forms an acute angle with the corresponding longitudinal central axis (not specifically shown). In some cases, the acute angle is 60° or less, and in others, it is 30° or less. In other words, the exemplary nozzle may, for example, form an angle of 30° or greater with the horizontal plane, and in other cases, an angle of 60° or greater with the horizontal plane.

[0094] Figure 8A A front elevation view of the distal end of a device according to at least some embodiments is shown. Specifically, Figure 8A Exemplary electrode 800 and exemplary electrode 802 are visible in the image. Figure 8A Many components and relationships of the electrodes (and 8B) are referenced above. Figures 4A-4C As discussed in 5A-5B, and will not be repeated here to avoid unduly lengthening the specification. As before, exemplary electrodes 800 and 802 are spaced apart from each other, thus forming a gap 804. Exemplary electrodes 800 and 802 each have a circular distal end or contact surface, which may be elliptical and, in some cases, spherical.

[0095] Exemplary electrodes 800 and 802 each define a longitudinal central axis. Specifically, electrode 800 defines a longitudinal central axis 806, and electrode 802 defines a longitudinal central axis 808. In the exemplary arrangement, longitudinal central axes 806 and 808 are coplanar and parallel. However, in other cases, longitudinal central axes 800 and 802 may be coplanar but not parallel. Figure 8A The nozzles on each electrode are also visible. Specifically, in Figure 8A Visible are orifices or nozzles 810 exposed on the outer surface of electrode 800 and orifices or nozzles 812 exposed on the outer surface of electrode 802. Exemplary nozzle 810 is fluidly coupled to a flow cavity within electrode 800. Similarly, exemplary nozzle 812 is fluidly coupled to a flow cavity within electrode 802.

[0096] Figure 8B It shows basically along Figure 8A The cross-sectional view of the electrode is taken from line 8B-8B and according to at least some embodiments. Specifically, Figure 8B The cross-sectional shape of the exemplary electrode shown is not necessarily polygonal and can actually be in the form of a closed curve with at least one axis of symmetry. As shown, the cross-sectional shape is oval, and specifically elliptical, but other closed curve shapes can be implemented. Each exemplary ellipse has long walls, and in the example shown, the long walls facing gap 804 are parallel. Although... Figure 8B The angle between the spray directions of the nozzle is shown to be approximately 90°, but the spray direction of the nozzle can be any suitable angle, such as 180° or less.

[0097] Figure 9A A front elevation view of the distal end of a device according to at least some embodiments is shown. Specifically, Figure 9A Exemplary electrode 900 and exemplary electrode 902 are visible in the image. Figure 9A Many components and relationships of the electrodes (and 9B) are referenced above. Figures 4A-4C As discussed in 5A-5B, and will not be repeated here to avoid unduly lengthening the specification. As before, exemplary electrodes 900 and 902 are spaced apart from each other, thus forming a gap 904. Exemplary electrodes 900 and 902 each have a circular distal end or contact surface, which may be elliptical and, in some cases, spherical.

[0098] Exemplary electrodes 900 and 902 each define a longitudinal central axis. Specifically, electrode 900 defines a longitudinal central axis 906, and electrode 902 defines a longitudinal central axis 908. In the exemplary arrangement, longitudinal central axes 906 and 908 are coplanar and parallel. However, in other cases, longitudinal central axes 906 and 908 may be coplanar but not parallel. Figure 9A The nozzles on each electrode are also visible. Specifically, in Figure 9A Visible are orifices or nozzles 910 exposed on the outer surface of electrode 900 and orifices or nozzles 912 exposed on the outer surface of electrode 902. Exemplary nozzle 910 is fluidly coupled to a flow cavity within electrode 900. Similarly, exemplary nozzle 912 is fluidly coupled to a flow cavity within electrode 902.

[0099] Figure 9B It shows basically along Figure 9A The cross-sectional view of the electrode is taken from line 9B-9B and according to at least some embodiments. Specifically, Figure 9B The cross-sectional shape of the exemplary electrode shown does not necessarily have two axes of symmetry. In the exemplary case shown, the cross-sectional shape is a chamfered polygon, specifically a convex polygon, with the smaller portion pointing away from gap 904. As shown, the smaller portion forms an angle of approximately 15° with the parallel tangent at the nozzle location. In other words, each electrode has a cross-sectional shape that is a convex polygon with one axis of symmetry, wherein the axis of symmetry is parallel to or coaxial with the line 914 connecting the longitudinal central axis. Figure 9B The exemplary cross-sectional shape can help guide the brine flow to the outer periphery of the electrode to aid the wetting process.

[0100] Figure 10A A front elevation view of an electrode according to at least some embodiments is shown. Figure 10B The illustration shows at least some embodiments Figure 10A A cross-sectional view of the electrode. Figure 10C A cross-sectional view of an electrode is shown, wherein the injection direction forms an acute angle with the longitudinal central axis of the electrode and according to at least some embodiments. Figure 10D It shows basically along Figure 10C The line 10D-10D and the cross-sectional view of the electrode according to at least some embodiments.

[0101] Also refer to Figure 10A-10DIn other exemplary embodiments, and taking electrode 1000 as representative of two electrodes, electrode 1000 defines a single orifice or nozzle 1004 having a jetting direction downward toward the tissue at the target site. Specifically, electrode 1000 forms an angled surface 1006, and nozzle 1004 is aligned with the angled surface 1006 such that fluid flow along the angled surface 1006 is directed toward the center of electrode 1000 at distal surface 1008 to help control the flow direction and ensure effective wetting of the distal surface. Referring to horizontal surface 1010 (e.g., horizontal surface 1010 forms a plane perpendicular to the longitudinal central axis of electrode 1000), angled surface 1006 produces an angle α between 90° and 120°, including 90° and 120° (approximately 113° in some cases) and approximately 113° in others. The distal surface 1008 in contact with the tissue has a reduced surface area to reduce resistance and improve movement across the tissue; for example, angle α of 113° provides a smaller contact surface area than angle α of 90°. Figure 10B An exemplary electrode 1000 defines a centrally positioned hole 1012 and an offset hole 1014 that generates a nozzle 1004. Thus, the centrally positioned hole 1012 and the offset hole 1014 are parallel to each other and to the longitudinal central axis of the electrode 1000.

[0102] Figure 10C An exemplary electrode 1000 defines a centrally positioned aperture 1012 and an angled aperture 1016 that generates a nozzle 1004. Therefore, the centrally positioned aperture 1012 and the angled aperture 1016 form an angle therebetween. Figure 10C As shown in the embodiment, the jetting direction defined by the orifice 1014 is angled away from the angled surface 1006 and away from the longitudinal central axis of the exemplary electrode 1000.

[0103] Depend on Figure 10A-10D The nozzle-defined jet direction in this embodiment improves device performance and reduces the risk of electrical bridging between electrodes by directing saline solution towards the tip rather than from the side of the device. This leads to more efficient energy utilization and thus reduces tissue damage caused by the device. The saline solution also takes a more direct path to the distal tip of the electrode, which effectively delivers the saline solution to the target tissue site, reducing tissue charring, improving movement over the tissue, and reducing the amount of saline solution used during the procedure. Furthermore, less fluid at the target tissue site increases device visibility, which can give clinicians more confidence in using the device and ultimately provide more accurate treatment.

[0104] The distance D from the proximal end of the saline outlet to the device tip is, for example, between 1.5 mm and 2.5 mm, and includes the range of 1.5 mm and 2.5 mm (approximately 1.75 mm in some cases), and approximately 1.75 mm in other cases. This dimension is chosen to ensure focused fluid delivery at the target tissue, without being too close to the tissue and causing the outlet to become blocked.

[0105] An exemplary angled surface 1006 facilitates passive flow of fluid toward the tip of electrode 1000. The horizontal surface 1010 can be oriented parallel to the direction of movement of the device, i.e., in and out. Figure 10A The page in the view. The cuts forming the angled surface 1006 and the horizontal surface 1010 result in a reduced surface area in contact with tissue (compared to the perfectly circular surface of the previous embodiment). The reduced surface area of ​​the ridge and the parallel positioning can enhance the movement of the device across tissue. Therefore, when the device is used dynamically, it may produce more consistent damage. The angled surface 1006 and the horizontal surface 1010 can also increase control of movement, ensuring that clinicians can effectively control the size and depth of the resulting damage.

[0106] Figure 11A A side elevation view of an electrode according to at least some embodiments is shown. Specifically, Figure 11A Electrode 1100 is shown as viewed from within the gap between the two electrodes. Figure 9A Many components and relationships of the electrodes of (and 9B) are related to the reference. Figures 8A-8B The same principles are discussed and will not be repeated here to avoid unduly lengthening the specification. An exemplary electrode 1100 defines two orifices or nozzles 1102 and 1104. Each nozzle 1102 and 1104 is associated with a groove or channel 1106 and 1108, respectively, which helps guide fluid flow toward the distal tip of the electrode, improving wetting and fluid delivery to tissue at the target site. Channel 1106 is discussed as representative; channel 1106 intersects with nozzle 1102 and extends from nozzle 1102 to the distal tip of electrode 1100. Channel 1106 has a closed bottom and an open top, wherein the open top intersects with the outer surface of electrode 1100. Channel 1106 defines a channel direction parallel to the longitudinal central axis (not specifically shown) of electrode 1100, but in other cases, the channel direction is not necessarily parallel to the longitudinal central axis.

[0107] Figure 11B A front elevation cross-sectional view of an electrode according to an exemplary embodiment is shown. Specifically, Figure 11B The cross-sectional view is parallel to Figure 11A The page is cut off in planar form, and cuts through one of channels 1106 or 1108. Therefore, in Figure 11BElectrode 1100 and mating electrode 1110 are visible. As before, electrodes 1100 and 1110 define a gap 1112 therebetween. Nozzle 1102 and corresponding nozzle 1114 define the injection direction into the gap 1112, wherein the angle between the injection directions of the nozzles of the same electrode adopts any suitable angle as discussed above. In use, brine is not only injected from the nozzles into the gap 1112, but a portion of the brine also deflects and travels along the corresponding channels (such as channel 1106 associated with nozzle 1102 and channel 1116 associated with nozzle 1114). The flow of brine along the channels contributes to the wetting of the distal surfaces of the electrodes.

[0108] Figure 12 A partial cross-sectional view of the device 104 according to at least some embodiments is shown. Specifically, Figure 12 Device 104 is shown. Figure 1 A cross-sectional view of a portion of the shank 110 and the elongated shaft 106. In an exemplary embodiment, each electrode (in...) Figure 12 (Not visible in the image) Dedicated fluid delivery tubes 1200 and 1202 formed of an electrically insulating material (e.g., nylon) are provided with brine. Each electrode is supplied with brine by a corresponding fluid delivery tube 1200 or 1202 extending along the length of an elongated shaft 106. Both fluid delivery tubes 1200 and 1202 are fluidly coupled to a single flushing cavity 1204 within a handle 110. Extending the length of the elongated shaft 106 by the fluid delivery tubes 1200 and 1202 reduces the possibility of bridging current through the delivery of brine. However, depending on the conductivity of the brine and other factors (e.g., applied voltage), branching of the flushing cavity 1204 can occur at any suitable location, such as closer to the electrode than the handle (e.g., within the elongated shaft 106), or at the proximal edge of the electrode. In the case where a single fluid delivery tube extends along the elongated shaft 106, the single fluid delivery tube can extend along the outer surface of the elongated shaft 106 or between the shaft (or ridge element) and the sheath.

[0109] Consider again the embodiment where the flushing flow cavity 1204 branches within the handle 110, with each fluid delivery tube 1200 and 1202 fluidly coupled to a corresponding flow cavity within a corresponding electrode. In this exemplary case, the conductivity between the two electrodes along the saline solution within the fluid delivery tubes 1200 and 1202 is lower than the direct conductivity between the two electrodes in contact with tissue. That is, to prevent electrical energy from traveling along the fluid delivery tubes, the shunt path length between the electrodes through tubes 1200 and 1202 is made sufficiently long, resulting in a lower conductivity between the electrodes through the saline solution and / or through the tissue at the target site (when filled with saline). The longer the fluid path through the two fluid delivery tubes, the longer the shunt path, and the lower the conductivity between the electrodes along the shunt path.

[0110] Still referencing Figure 12 In an exemplary case, energy delivery to the electrodes is via a conductive tube. Figure 12 Two conductive tubes are shown, including conductive tube 1204 shown in cross-section, and conductive tube 1206 (only partially visible at its proximal end). Conductive tubes 1206 and 1208 extend parallel to each other and form part of an elongated shaft 106. Each conductive tube is coupled to a corresponding conductor in a flexible multi-conductor cable 142. Figure 1 Conductive tubes 1206 and 1208 extend from the shank 110 along an elongated axis 106 to the electrode. Each conductive tube 1206 and 1208 contains a fluid delivery tube 1200 and 1202, respectively. In some cases, each fluid delivery tube is coaxial with its conductive tube, but this is not necessary.

[0111] The exemplary conductive tubes are physically separated, parallel, and electrically insulated from each other by non-conductive ridges 1210 extending from the shank 110 to the electrodes. The outer surface of the conductive tubes may be electrically insulated from a coating or sheath 1212 covering the tubes and ridges 1210. The sheath 1212 may form a single smooth outer surface of the elongated shaft 106. In an alternative embodiment, each conductive tube is individually insulated using a coating or sheath.

[0112] Figure 13 A side elevation view of an electrode according to at least some embodiments is shown, and exemplary connections between the electrode, the electrode conductive tube, and the ridge are illustrated for the purpose of discussing these connections. Specifically, electrode 1300 represents any electrode previously discussed. Working from left to right in the figure, exemplary electrode 1300 includes a proximal boss 1302, an annular ring 1304, an annular groove 1306, and an exemplary exposed portion 1308. Boss 1302 has an outer diameter designed and configured to accommodate the conductive tube (e.g., Figure 12 The inner diameter of the tube 1206 is extended and contracted, and it is electrically connected to the tube. Therefore, the boss 1302 is received within the conductive tube, and the tube is adjacent to the shoulder 1308 formed between the boss 1302 and the annular ring 1304. As will be shown in more detail below, the ridge 1210 (e.g., Figure 12 The electrode 1300 terminates at a lug, and each lug is connected to a corresponding annular groove 1306 to maintain the relationship between the electrode 1300 and its corresponding conductive tube.

[0113] Figure 14 A perspective view of the distal end of a device according to at least some embodiments is shown. Specifically, Figure 14 Exemplary electrode 1300 and mating electrode 1400 are visible. Also visible are exemplary conductive tube 1206 and conductive tube 1208 associated with electrode 1400. Exemplary ridge 1210 is located between conductive tubes 1206 and 1208. Figure 14In this arrangement, the boss (not visible) of electrode 1300 extends and retracts within conductive tube 1206, and conductive tube 1206 abuts a shoulder created by an annular ring 1304. Similarly, the boss (not visible) of electrode 1400 extends and retracts within conductive tube 1208, and conductive tube 1208 abuts a shoulder created by an annular ring 1404. An exemplary ridge 1210 terminates at lugs 1406 and 1408. Lug 1406 is disposed within an annular groove 1306 of electrode 1300. Similarly, lug 1408 is disposed within an annular groove 1410 of electrode 1400. Lugs 1406 and 1408 help maintain alignment of ridge 1210 with conductive tubes 1206 and 1208, and help maintain electrodes 1300 and 1400 in operative relationship with conductive tubes 1206 and 1208, respectively.

[0114] For reference Figure 1 As discussed, in some cases, peristaltic pump 124 ( Figure 1 The saline solution is supplied to the electrodes. A peristaltic pump is a positive displacement pump that provides volume-controlled flow. However, peristaltic pumps deliver flow with pulses caused by the interaction of the rotating head against a stationary component; these pulses are called fluid flow pulsation. Reducing fluid flow pulsation from the peristaltic pump makes clotting more consistent. This specification now turns to an exemplary system for reducing fluid flow pulsation.

[0115] Figure 15 A simplified cross-sectional view of a conductive tube, a fluid delivery tube, and an electrode according to at least some embodiments is shown. Specifically, Figure 15 The layout and construction are designed to reduce fluid flow pulsation by using flow restrictors and compliant piping. Figure 15 An exemplary conductive tube 1500 is shown, which represents any of the conductive tubes previously discussed. Disposed within the conductive tube 1500 is a fluid delivery tube 1502, which also represents any of the fluid delivery tubes previously discussed. According to these embodiments, the fluid delivery tube 1502 has an outer diameter smaller than the inner diameter of the conductive tube 1500, thus forming a ring-shaped volume 1504 between the outer diameter of the fluid delivery tube 1502 and the inner diameter of the conductive tube 1500. Figure 15 In the diagram, the fluid delivery tube 1502 is shown coaxial with the longitudinal central axis of the conductive tube 1500; however, in some cases, the fluid delivery tube may be pressed against the inner diameter under gravity, particularly under the weight of the brine flowing within the inner diameter of the fluid delivery tube 1502.

[0116] Electrode 1506 is disposed at the distal end of conductive tube 1500, and electrode 1506 represents any of the electrodes discussed previously. A flow restrictor 1508 is fluidly disposed between the fluid delivery tube 1502 and the flow cavity within electrode 1506. Flow restrictor 1508 can take any suitable form, such as an orifice or tortuous path device. In some cases, flow restrictor 1508 is a separate element physically disposed between fluid delivery tube 1502 and the flow cavity of electrode 1506. In other cases, flow restrictor 1508 can be implemented in another part of the electrode, such as a boss of the electrode (e.g., Figure 13 (The boss 1302). Placing the flow restrictor 1508 in the path of the brine increases resistance to flow and increases back pressure. The fluid delivery pipe 1502 upstream of the flow restrictor 1508 is made of compliant piping. The compliance of the fluid delivery pipe 1502 is used to dampen the pulses generated by the upstream peristaltic pump. That is, the outer diameter of the fluid delivery pipe 1502 expands and contracts within the annular volume 1504 to provide pressure damping.

[0117] In other cases, the flow restrictor 1508 may be implemented as a portion of the fluid delivery tube 1502 itself. For example, a portion of the fluid delivery tube 1502 may be implemented as a rigid or non-compliant tube with a reduced inner diameter. The rigid or non-compliant portion may be fluidly disposed before or upstream of the electrode 1506. In these cases, the compliant and / or flexible tubular member 122 of the upstream portion of the fluid delivery tube 1502 ( Figure 1 The compliance of the fluid can provide fluid pressure damping.

[0118] Figure 16 A simplified cross-sectional view of a portion of a fluid delivery tube according to at least some embodiments is shown. Specifically, Figure 16 A fluid delivery tube 1600 is shown, representing any of the fluid delivery tubes previously discussed. The fluid delivery tube 1600 includes a first tube portion 1602 fluidly coupled to a second tube portion 1604. In the exemplary system, the first tube portion 1602 has an inner diameter, and the second tube portion 1604 has an inner diameter smaller than that of the first tube portion 1600, thus forming a flow limiter. As shown, the second tube portion 1604 has an outer diameter smaller than the inner diameter of the first tube portion 1602. The first tube portion 1602 extends and retracts over the second tube portion 1604 and is held in place by an annular plug 1606. The annular plug 1606 forces the second tube portion 1604 to be coaxial with the first tube portion 1602, thus forming an annular volume 1608 between the inner diameter of the first tube portion 1602 and the outer diameter of the second tube portion 1604.

[0119] When brine is pumped into the fluid delivery line 1600, the brine traps air within the toroidal volume 1608. The trapped air creates an air cushion within the toroidal volume 1608. This air cushion is compressed with pulses and thus serves to provide pressure damping.

[0120] In addition to fluid delivery, various embodiments may also include the option of aspirating fluid from the treatment site. The aspirated fluid may include saline, blood, and / or fumes generated during clotting. Removing blood can help locate the source of bleeding. Removing fumes can aid in visualization of the target site. Removing saline can help reduce excess saline that may accumulate around the electrode, potentially wasting energy, and reduces the energy required to enter the tissue to cause clotting.

[0121] Figure 17 A perspective view of the distal end of a device according to at least some embodiments is shown. Specifically, Figure 17 Exemplary electrodes 1300 and 1400, conductive tubes 1206 and 1208, ridge 1210, and lugs 1406 and 1408 disposed in their respective annular grooves are shown. Figure 17 An exemplary device is also shown that can define an aspiration port 1700 disposed between two electrodes 1300 and 1400. The aspiration port 1700 may be located or offset towards the tissue at the distal end of the device facing the target site, making the aspiration port 1700 closer to the tissue for better aspiration of blood and saline. Alternatively, placing the aspiration port 1700 or an additional aspiration port on the opposite side of the tissue away from the target site will primarily remove fumes.

[0122] The suction orifice 1700 may have a single inlet port or multiple inlet ports fluidly connected together. Using multiple inlets can help maintain suction flow if one inlet port becomes blocked. Potential blockage is unlikely to be caused by tissue debris, as coagulation tends not to form debris; however, coagulated blood may block the inlet.

[0123] An exemplary aspiration orifice 1700 can be fluidly coupled to a fluid delivery device comprising a tube or conduit extending along an elongated axis 106 and can be fluidly coupled to a vacuum source. In one exemplary embodiment, the aspiration conduit may be defined within a ridge 1210. Vacuum pressure control or siphoning can be implemented to limit the force of the vacuum. Although aspiration can remove some saline from the target site and electrode region, not all saline from the electrode region should be removed, as a dry electrode surface reduces clotting properties and triggers the need to rewet the electrode before applying energy. Additionally, if aspiration and delivery are performed simultaneously, aspiration can be controlled to reduce the intake of saline delivered directly from the nozzle into the aspiration orifice. This can increase the likelihood of electrical bridging between electrodes and again cause insufficient coating of the electrodes with saline, thus affecting clotting. Preferably, the aspiration orifice should be spaced 5-8 mm proximally from the electrode tip and 3-5 mm from the delivery orifice.

[0124] In another scenario, the suction orifice can be positioned adjacent to or through the outer lateral portion of each electrode. Removing fluid from the outer portion of the electrode helps maintain direct tissue effect between the electrodes and reduces thermal diffusion laterally or radially away from the gap between the two electrodes.

[0125] In the exemplary case, aspiration can be selectively controlled. That is, although saline delivery can be controlled in conjunction with the coagulation controller 116 ( Figure 1 Operable communication allows for simultaneous delivery of saline and energy, but aspiration can be more selectively controlled as a clinician's option. Advantageously, selective control of aspiration can replace the need for a separate aspiration tool used during surgery and reduce procedural costs. Selective aspiration control can be achieved via the speed of a movable valve or pump (e.g., an attached peristaltic pump). The controls can communicate with a button or foot switch on the handle (not shown).

[0126] Figure 19 A perspective view of an apparatus according to at least some embodiments is shown. Specifically, Figure 19 The device 104 is shown, which includes electrodes 1300 and 1400, an elongated shaft 106, a handle 110, a button 148, a flexible multi-conductor cable 112, and a flexible tubular member 122. Figure 19An exemplary aspiration portion 1900 is also shown. An exemplary aspiration port 1900 is fluidly coupled to an aspiration lumen 1902. Both the aspiration port 1900 and the aspiration lumen 1902 are fluidly coupled to an aspiration delivery conduit (not visible) that extends along the length of an elongated axis 106 and within a handle 110. The aspiration lumen 1902 may be fluidly coupled to a vacuum source, such as a peristaltic pump or a wall-mounted aspiration port located in a hospital room. Clinicians selectively control aspiration by moving their fingers to cover and uncover the aspiration port 1900. In operation, when the aspiration port 1900 is uncovered, there is no aspiration or reduced aspiration through the aspiration port at the distal end 108 of the device 104. In contrast to continuous aspiration, selective control reduces the likelihood of obstruction of the aspiration lumen by limiting aspiration to a time chosen by the clinician. The aspiration port 1900 may be selectively covered while delivering energy to control and modulate the desired tissue effect. This instruction manual now turns to considerations regarding the speed or aggressiveness of controlling blood clotting.

[0127] The rate or positivity of coagulation can be controlled, at least in part, based on the energy delivered to the electrode. In some cases, clinicians choose the applied voltage setting as the coagulation energy setting. Within an exemplary range of applied voltage settings between 110 volts (V) and 200 V, and including both 110 volts (V) and 200 V, 110 V can be considered a lower coagulation energy setting, and 200 V a higher one. Changing the applied voltage setting will alter the RF voltage applied to the electrode between approximately 120 V RMS and approximately 165 V RMS. A higher applied voltage setting results in a higher applied voltage and affects more tissue around the electrode, both deeper and wider, for example, through faster dehydration and a larger volume of processed tissue.

[0128] Relatedly, consider reactivating button 150 ( Figure 1 Activation of button 150 supplies energy to the tissue based on the applied voltage setting selected by the clinician. When activated, MAX button 152 provides a higher level of energy output than the applied voltage setting to enhance coagulation. MAX button 152 can automatically communicate with the controller to supply an RF output voltage to the electrodes at a higher voltage level, such as the upper end of the applied voltage range (e.g., 165V). Alternatively, when MAX button 152 is activated, the applied voltage can be increased by a percentage of the applied voltage setting, increased by a fixed value, or increased by a fixed setting higher than the selected value. For example, if the applied voltage setting is 120V, activation of button 152 can communicate with the controller to supply a voltage 30V higher or 30% higher.

[0129] In addition to enabling clinicians to select from a range of applied voltage settings (and therefore an applied energy range), according to exemplary embodiments, clinicians can also select from multiple flow rate settings for saline. In exemplary embodiments, clinicians may select from three or more flow rate settings, and in some cases from five flow rate settings. Each flow rate setting determines the saline flow rate during use at each applied voltage setting. Higher applied voltages can cause some evaporation in the delivered fluid, and therefore at higher applied voltage settings, an increased flow rate can be implemented to balance evaporation and maintain a more consistent fluid coating around the electrodes. To ensure that an appropriate flow range is provided, the coagulation controller 116 can automatically adjust the flow rate according to the applied voltage setting.

[0130] Figure 20 A graph showing the applied voltage relative to the pump speed according to at least some embodiments is presented. Specifically, the vertical axis shows the applied voltage in volts (RMS), ranging from a low of 120V to a high of 165V in 5V increments. This applied voltage range of 120V to 165V in 5V increments can be correlated with an applied voltage setting range of 110V to 200V in 10V increments. However, in other cases, the applied voltage setting value can be directly related to the applied voltage. The horizontal axis shows the pump speed of the peristaltic pump in revolutions per second (RPS). Since the pump speed of the peristaltic pump is directly related to the flow rate, the horizontal axis can be considered equivalently to represent the flow rate. In the example graph, five different flow rates are shown, representing five different flow rate settings. Therefore, this graph illustrates a system where a clinician can select from one of ten applied voltage settings and one of five flow rate settings for coagulation.

[0131] exist Figure 20 In the examples shown, the selected flow rate setting results in a single flow rate corresponding to an applied voltage range (but less than all applied voltages). For example, consider flow rate 2. For all applied voltages from 120V to 150V (inclusive), exemplary flow rate 2 provides a peristaltic pump speed slightly above 0.35 RPS. However, at the threshold applied voltage (in the exemplary 155V), the pump speed, and therefore the flow rate, increases to ensure proper wetting of the electrodes. Figure 20The graph might suggest the opposite; the exemplary system does not implement mathematically linear flow control between any two applied voltages. Instead, clinicians can select applied voltages in 5V increments (by selecting applied voltage settings in 10V increments), and thus the saline flow rate varies stepwise at the threshold voltage. Considering exemplary flow rate 2, at an applied voltage of 150V, the pump speed exceeds 0.35 RPS, and at an applied voltage of 155V, the pump speed exceeds 0.45 RPS. In the exemplary system, clinicians cannot select the applied voltage setting that results in an applied voltage between 150V and 155V, and therefore there is no intermediate pump speed setting between 150V and 155V. However, in other cases, linear interpolation for the pump speed is possible as the applied voltage (and applied voltage setting) increases.

[0132] According to an exemplary embodiment, the applied voltage is controlled in an open-loop manner. That is, the clinician selects an applied voltage setting, and the applied voltage setting results in an applied voltage at the expected impedance between the electrodes. However, variations in the actual impedance between the electrodes affect the applied voltage. For example, applying energy to the electrodes when they are held in air (e.g., higher impedance) may result in a higher applied voltage. Conversely, applying energy to the electrodes when they are bridged with saline and thus shunt or short-circuit the electrodes (e.g., lower impedance) may result in a lower applied voltage. In some embodiments, the coagulation controller 116 does not attempt to compensate for variations in impedance; instead, based on the applied voltage setting, the coagulation controller operates in a manner that produces an applied voltage at the expected impedance, but does not change its operation due to variations in the actual impedance around the expected impedance.

[0133] Similarly, in an exemplary embodiment, the peristaltic pump speed is controlled in an open-loop manner. That is, the clinician selects a pump speed setting, and this setting results in a pump speed (and therefore a flow rate). Changes in the applied voltage (e.g., caused by impedance fluctuations) do not alter the pump speed. In other words, in some embodiments, the coagulation controller 116 does not attempt to compensate for actual applied voltage changes caused by impedance fluctuations. However, when the applied voltage is intentionally increased, for example by activating the MAX button 152, the pump speed may increase accordingly. In an exemplary embodiment, the coagulation controller 116 implements this by using a lookup table, as shown below. Figure 20 The flow control is illustrated by applying voltage. The coagulation controller 116 receives the applied voltage or the applied voltage setting, and receives the flow rate setting, and performs a lookup in a lookup table to select the pump speed accordingly.

[0134] Figure 21 An exemplary coagulation controller 116 according to at least some embodiments is illustrated in block diagram form. Specifically, the example coagulation controller 116 has a control system 2100 coupled to various internal and external components. Figure 21 In the exemplary system, the control system 2100 takes the form of a microcontroller, having a processor 2102 electrically connected to segments of random access memory (RAM) 2104, read-only memory (ROM) 2106, digital-to-analog (D / A) output 2108, analog-to-digital (A / D) input 2110, digital input (D / I) 2112, and communication logic (COM) 2114. Although the control system 2100 is shown as a microcontroller, in other cases, individual components (i.e., individual processors, RAM, ROM, etc.) can be combined to achieve functionality, or other means such as field-programmable gate arrays (FGPA), application-specific integrated circuits (ASICs), programmable logic controllers (PLCs), programmable logic devices (PLDs), and discrete components can be used to replace or supplement the aforementioned components. The exemplary RAM 2104 can be the working memory of the processor 2102. The ROM 2106 can store programs and data in a non-volatile manner, and the processor 2102 can copy programs and data from the ROM 2106 to the RAM 2104 during program execution. In some cases, ROM 2106 serves as a long-term storage location for a lookup table that associates the applied voltage with flow rate settings to control the speed of the peristaltic pump, and thus the lookup table can also be copied to RAM 2104 during operation. Digital-to-analog output 2108 can be used to provide analog signals to other devices within the coagulation controller 116, such as the pump motor speed controller 2116 (discussed more below) and the RF voltage generator 2118. Analog-to-digital input 2110 can provide the control system 2100 with the ability to read analog signals. Digital input 2112 can be used to receive information into the control system 2100, such as information from foot pedal devices 138 / 140, button 134 on the coagulation controller 116, or button 148 on device 104. Finally, communication logic 2114 can be used for packet-based communication with internal or external devices, such as interface device 132, or as an alternative to communicating with the pump motor speed controller 2116.

[0135] RF voltage generator 2118 defines a first connection or first lead 2120 that is coupled to a first terminal 2122 (e.g., an electrical pin) in controller connector 118. In use, electrical pin 2124 in rod connector 114 couples the first terminal 2122 to the distal end of device 104. Figure 1 The first electrode is on the controller connector 114. Similarly, the RF voltage generator 2118 defines a second connection or second lead 2126 that is coupled to a second terminal 2128 (e.g., an electrical pin) in the controller connector 118. In use, the electrical pin 2131 in the rod connector 114 is coupled to another electrode on the distal end of the device 104.

[0136] RF voltage generator 2118 is configured to generate coagulation energy at a coagulation frequency. According to an exemplary embodiment, the coagulation frequency generated by RF voltage generator 2118 can be between about 5 kHz and 20 MHz, in some cases between about 30 kHz and 2.5 MHz, in others between about 50 kHz and 500 kHz, and in specific cases about 100 kHz. As discussed above, the coagulation voltage can be between 120 V and 165 V RMS and includes 120 V and 165 V RMS. In the illustrated exemplary system, the generated RF voltage 2118 receives commands via a digital-to-analog output 2108; however, RF voltage generator 2118 can provide commands in any suitable form, such as digitally (e.g., via a digital output, not specifically shown) or via a packet-based message (e.g., via communication logic 2114).

[0137] The coagulation controller 116, and more precisely the control system 2100, enables control of coagulation, including control of the applied voltage and the speed of the peristaltic pump. Regarding pump speed, the exemplary coagulation controller 116 implements a motor speed controller 2130 coupled to a motor 2132, which rotates the peristaltic pump 124. The motor 2132 can take any suitable form. For example, the motor 2132 can be a DC motor, and therefore the motor speed controller 2130 provides a DC voltage to the motor, which controls the speed of the output shaft. In other cases, the motor 2132 can be an AC motor, and therefore the motor speed controller 2130 provides an AC voltage with varying voltage and frequency, which controls the speed of the output shaft. In still other cases, the motor 2132 can be a pneumatic motor, and therefore the motor speed controller 2130 provides air with varying pressure, where the pressure controls the speed of the output shaft. Thus, regardless of the type of motor 2132 implemented, the motor speed controller 2130 controls the speed of the motor in response to commands provided from the control system 2100. Although in the exemplary system, commands to the motor speed controller 2130 are shown as analog signals, in other cases, the motor speed controller 2130 may receive commands in any suitable form, such as digital (e.g., via a digital output, not specifically shown) or in a packet-based message (e.g., via communication logic 2114). Finally, although the motor 2132 is shown as directly coupled to the peristaltic pump 124, in other cases, various gears and / or belts may be used to transfer the rotational motion of the shaft of the motor 2132 to the peristaltic pump 124. Figure 21 Based on the rotary peristaltic pump, but those with common skills and who benefit from this disclosure can modify the system to use it with other types of outflow pumps, such as linear peristaltic pumps or centrifugal pumps combined with flow measurement devices (because the flow rate through a centrifugal pump is not as directly related to velocity as that of a positive displacement pump (such as a peristaltic pump).

[0138] It should be noted that Figure 21 The embodiments show the peristaltic pump 124 as an internal or integrated device (e.g., within the same housing) of the coagulation controller 116; however, in other cases, the peristaltic pump 124 may be an external component of the coagulation controller 116. Furthermore, although Figure 21 Only one set of connected pump motor speed controller, motor and peristaltic pump is shown, but the coagulation controller can implement two or more sets (e.g., a second pump to control aspiration).

[0139] Therefore, in an exemplary embodiment, the control system 2100 includes RAM 2104 and ROM 2106 (and possibly other non-transitory storage media) storing instructions for implementing the coagulation control strategy discussed above. When executed by a processor, exemplary instructions may cause the coagulation controller to: apply RF energy between the first and second electrodes; and simultaneously allow saline solution to flow through the electrodes of device 104. Other exemplary instructions, when executed by processor 2102, may cause the coagulation controller to: receive instructions for flow rate settings from a plurality of flow rate settings; receive instructions for applied voltage settings; provide energy to the electrodes at a voltage range determined by the applied voltage settings, the energy varying over time according to the impedance experienced between the first and second electrodes; and simultaneously pump conductive fluid at a flow rate selected by the coagulation controller from a table associating applied voltage settings and flow rate settings, and the flow rate remains constant as the provided energy varies over time.

[0140] The foregoing discussion is intended to illustrate the principles and various embodiments of the invention. Many variations and modifications will become apparent to those skilled in the art once the foregoing disclosure is fully understood. The following claims are intended to be construed as including all such variations and modifications.

Claims

1. An electrosurgical device, comprising: The handle has a flushing cavity disposed therein; A cable connected to the proximal end of the handle, the cable defining a first electrical conductor and a second electrical conductor; An elongated shaft, the elongated shaft being connected to the shank and defining a distal end opposite the shank; A first electrode is disposed on the distal end of the elongated shaft and electrically connected to the first electrical conductor, the first electrode defining a circular contact surface opposite the distal end of the elongated shaft, a non-circular inner cross-section, and a first longitudinal axis. The second electrode is disposed on the distal end of the elongated shaft and electrically connected to the second electrical conductor. The second electrode defines a circular contact surface opposite to the distal end of the elongated shaft, a non-circular inner cross-section, and a second longitudinal axis coplanar with the first longitudinal axis. A first nozzle defined by the first electrode, the first nozzle being fluidly coupled to the flushing cavity, the first nozzle defining a first spray direction between 0° and 90° relative to a line intersecting both the first longitudinal axis and the second longitudinal axis and including 0° and 90°; as well as A second nozzle defined by the second electrode, the second nozzle being fluidly coupled to the flushing cavity, the second nozzle defining a second spray direction between 0° and 90° relative to the line and including 0° and 90°; The first nozzle and the second nozzle are associated with a first channel and a second channel, respectively. The first channel and the second channel intersect with the first nozzle and the second nozzle, respectively. The first channel and the second channel advance from the first nozzle and the second nozzle to the distal tips of the first electrode and the second electrode, respectively. The first channel and the second channel have a closed bottom and an open top, wherein the open top intersects with the outer surface of the first electrode and the second electrode.

2. The electrosurgical device according to claim 1, further comprising: A third nozzle defined by the first electrode, the third nozzle being fluidly coupled to the flushing cavity, the third nozzle defining a third jet direction, the first jet direction and the third jet direction defining a first angle bisected by the line, and the first angle being equal to or less than 180°; A fourth nozzle defined by the second electrode, the fourth nozzle being fluidly coupled to the flushing cavity, the fourth nozzle defining a fourth jet direction, the second jet direction and the fourth jet direction defining a second angle bisected by the line, and the second angle being equal to or less than 180°.

3. The electrosurgical device according to claim 2: Wherein the first angle is 180°, the first nozzle is on the gap side of the first longitudinal axis, and the third nozzle is on the gap side of the first longitudinal axis; and The second angle is 180°, the second nozzle is on the gap side of the first longitudinal axis, and the fourth nozzle is on the gap side of the first longitudinal axis.

4. The electrosurgical device according to claim 2: Wherein the first angle is 170° or less; and The second angle is 170° or less.

5. The electrosurgical device of claim 4, further comprising that the orientation of the first nozzle and the third nozzle are mirror images of the positions of the second nozzle and the fourth nozzle, respectively, spanning the gap between the first electrode and the second electrode.

6. The electrosurgical device according to claim 2, wherein the first jet direction, the second jet direction, the third jet direction and the fourth jet direction are in a common plane.

7. The electrosurgical device according to claim 2, further comprising: The first injection direction and the third injection direction form a first acute angle with respect to the first longitudinal axis, and the first acute angle opens toward the circular contact surface of the first electrode; and The second injection direction and the fourth injection direction form a second acute angle with respect to the second longitudinal axis, and the second acute angle opens toward the circular contact surface of the second electrode.

8. The electrosurgical device according to claim 1, wherein the circular contact surface of the first electrode is an ellipsoid, and wherein the circular contact surface of the second electrode is an ellipsoid.

9. The electrosurgical device of claim 1, wherein the circular contact surface of the first electrode is spherical, and wherein the circular contact surface of the second electrode is spherical.

10. The electrosurgical device of claim 1, wherein the first electrode is rigidly coupled to the elongated shaft and is immovable relative to the second electrode, and the second electrode is rigidly coupled to the elongated shaft and is immovable relative to the first electrode.

11. The electrosurgical device of claim 1, wherein the line between the vertex of the circular contact surface of the first electrode and the vertex of the circular contact surface of the second electrode is perpendicular to the first longitudinal axis of the first electrode.

12. The electrosurgical device of claim 1, wherein the first electrode and the second electrode each have a polygonal cross-section.

13. The electrosurgical device of claim 12, wherein the first electrode and the second electrode each have a square cross-section.

14. The electrosurgical device of claim 1, wherein the first electrode and the second electrode each have a square cross-section with chamfered corners.

15. The electrosurgical device of claim 1, wherein the second longitudinal axis is parallel to the first longitudinal axis.

16. The electrosurgical device of claim 4, wherein the first angle is 120° or less.

17. The electrosurgical device of claim 4, wherein the first angle is 90° or less.

18. The electrosurgical device of claim 4, wherein the first angle is 60° or less.

19. The electrosurgical device of claim 4, wherein the second angle is 120° or less.

20. The electrosurgical device of claim 4, wherein the second angle is 90° or less.

21. The electrosurgical device of claim 4, wherein the second angle is 60° or less.

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