JP6698113B2 - Electrosurgical system and method - Google Patents

Description

  Electrosurgical systems are used by surgeons to perform specific functions in surgical procedures.

  Within these medical procedures, it may be necessary to treat more than one type of tissue or to produce more than one effect of the tissue. Existing electrosurgical systems are typically designed with limited functionality and are not always particularly effective for treating different types of tissue. In the event that the medical procedure requires treatment of multiple types of tissue, the use of a single device may have adverse consequences in certain aspects of the medical procedure, and the user may It may be necessary to utilize or switch between some surgical devices to achieve the desired result. For example, certain electrosurgical procedures on the knee or shoulder may require several different modes of operation to effectively treat different types of tissue. Each mode utilizes a different amount of energy, and in the related art, each mode may involve the use of different electrosurgical wands and different types of electrosurgical controllers. In some cases, where multiple electrosurgical wands would have been used to obtain better therapeutic results, the surgeon would have the right wand and wand to reduce the cost of the medical procedure. And/or may refrain from using electrosurgical controllers.

U.S. Pat. No. 5,697,882 US Pat. No. 6,355,032 US Pat. No. 6,149,120 US Pat. No. 6,296,136 US Patent No. 8192424 U.S. Pat. No. 6,142,992 US Pat. No. 6,235,020 U.S. Pat. No. 8257350

Plasma Physics, by R.J. Goldston and P.H. Rutherford, the Plasma Physics Laboratory of Princeton University (1995)

  Any benefit that makes it easier for the surgeon to treat and achieve better results would provide a competitive advantage.

  For a detailed description of example embodiments, reference is made to the accompanying drawings.

6 illustrates an electrosurgical system according to at least some embodiments. FIG. 6 illustrates an elevational view of an electrosurgical wand according to at least some embodiments. FIG. 6A shows a cross-sectional elevation view of an electrosurgical wand according to at least some embodiments. FIG. 4A shows a perspective view of a screen electrode and a distal end of an electrosurgical wand including the screen electrode, according to at least some embodiments. FIG. 6 shows an electrical block diagram of a controller according to at least some embodiments. 5A-5C show example graphs relating output RF energy and aspiration flow rates for various modes in accordance with at least some embodiments. 6 illustrates a method in block diagram form, in accordance with at least some embodiments.

NOTES AND NOMENCLATURE Certain terms are used throughout the following description and claims to refer to particular system components. As one of ordinary skill in the art will appreciate, companies that design and manufacture electrosurgical systems may refer to components by different names. This specification does not intend to distinguish between components that differ in name but not function.

  In the following description and in the claims, the terms "comprising" and "comprising" are used in the sense of being open-ended and therefore to be interpreted as meaning "including but not limited to". .. Similarly, the term "couple" is intended to mean either an indirect or a direct connection. As such, when the first device couples to the second device, the connection can be through a direct connection or an indirect connection through another device or connection.

  References to a single item include the possibility that multiple identical items exist. More specifically, as used in this specification and the appended claims, "a", "said", and "the" indicating a single are such that the text clearly If not clearly stated, it includes plural. Further, it should be noted that the claims may be described without including any additional components. Thus, this reference acts as an antecedent to the use of exclusive terms such as "simply" and "only," as well as with respect to the recitation of elements of the claims and the use of "negative" limitations. Finally, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It should be understood to have

  “Ablation” shall mean the removal of tissue based on its interaction with the plasma.

  "Ablation mode" shall refer to one or more characteristics of ablation. "Absence of ablation" (that is, absence of plasma) shall not be considered as "ablation mode". The coagulation mode shall not be considered as the "ablation mode".

  “Active electrode” shall mean the electrode of an electrosurgical wand that produces the effect of altering the electrically introduced tissue when brought into contact with or in close proximity to the targeted tissue for treatment. ..

  The "return electrode" is the electrode of an electrosurgical wand that serves to provide a current path for charge to the active electrode and/or the tissue itself that is electrically introduced to the target tissue for treatment. It means an electrode of an electrosurgical wand that does not produce a varying effect.

  “Electric motor” shall include alternating current (AC) motors, direct current (DC) motors and stepping motors.

  "Controlling fluid flow rate" means controlling volumetric flow rate. Controlling the applied pressure so as to maintain the set pressure (for example, suction pressure) independently of the volumetric flow rate of the liquid caused by the applied pressure shall not be considered as "control of fluid flow rate". However, changing the applied pressure so as to maintain the set volume flow rate of the liquid is considered as “control of the fluid flow rate”.

  "Substantially" shall mean with respect to the exposed surface area of the electrodes that the exposed surface area between the two electrodes is not equal or different by more than 25 percent.

  Fluid conduits that are said to be “in” a long shaft are not only the individual fluid conduits that physically reside in all or part of the interior volume of the long shaft, but the interior volume of the long shaft itself is the fluid conduit. It is also intended to include the situation where certain or individual fluid conduits are connected along the length of the long shaft or a portion thereof.

  When a range of values is provided, all values intervening between the upper and lower limits of that range and any other existing or intervening value within its declared range are included within the scope of the invention. Understood as one. Also, any and all features of the described inventive variations are described and claimed independently or in combination with any one or more of the features described herein.

  All existing subject matter referred to herein (eg, literature, patents, patent applications and hardware) may be contradictory to the subject matter of the invention (in which case such subject matter is present herein). Except in the case of preference), the disclosure is incorporated herein by reference in its entirety. The referenced items are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present invention is not entitled to antedate such material by virtue of prior invention.

DETAILED DESCRIPTION Before describing the various embodiments in detail, the present invention is herein described as various modifications and improvements may be made and equivalents may be replaced without departing from the spirit and scope of the invention. It should be understood that it is not limited to the particular variations described. As will be apparent to one of ordinary skill in the art reading this disclosure, each of the individual embodiments described and shown herein may be embodied in several other embodiments without departing from the scope or spirit of the invention. It has individual components and features that can be easily separated from or combined with any of the features. In addition, many modifications may be made to adapt a particular situation, material, composition of matter, process, process operation or step, to the objective, spirit or scope of the present invention. All such modifications are intended to be within the scope of the claims appended hereto.

  Various embodiments are directed to electrosurgical methods and associated electrosurgical systems. Specifically, various embodiments are directed to an electrosurgical system having multiple modes of operation configured for treatment of a particular type of targeted tissue or desired electrosurgical effect, and a single electrosurgical system. It is implemented by a surgical wand and a single electrosurgical controller. In the exemplary embodiment, the multiple modes of operation are implemented by a single active electrode of the electrosurgical wand. The present description first refers to an exemplary system to guide the reader.

  FIG. 1 illustrates an electrosurgical system 100 according to at least some embodiments. Specifically, electrosurgical system 100 includes an electrosurgical wand 102 (hereinafter "wand 102") coupled to an electrosurgical controller 104 (hereinafter "controller 104"). Wand 102 includes an elongated shaft 106 that defines a distal end 108. The elongate shaft 106 further defines a handle or proximal end 110 where the surgeon grips the wand 102 during a surgical procedure. The wand 102 further includes a flexible multi-conductor cable 112 that houses one or more electrical leads (not specifically shown in FIG. 1), the flexible multi-conductor cable 112 terminating within a wand connector 114. .. As shown in FIG. 1, the wand 102 is coupled to the controller 104, such as by the controller connector 120 on the exterior surface of the housing 122 (front face in the case of the exemplary FIG. 1).

  Although not visible in FIG. 1, in some embodiments wand 102 has one or more internal fluid conduits coupled to an externally accessible tubular member. As shown, the wand 102 has a flexible tubular member 116 used to provide suction at the distal end 108 of the wand. According to various embodiments, tubular member 116 is coupled to peristaltic pump 118, which is illustratively shown as an internal component with controller 104 (ie, at least within housing 122 of controller 104). Partially located). In other embodiments, the housing of the peristaltic pump 118 may be separate from the housing for the controller 104 (as shown by the dotted line in the figure), but in any event, the peristaltic pump operates on the controller 104. Be combined as possible.

  The peristaltic pump 118 includes a rotor portion 124 (hereinafter, simply “rotor 124”) and a stator portion 126 (hereinafter, simply “stator 126”). The flexible tubular member 116 is coupled within the peristaltic pump 118 between the rotor 124 and the stator 126, and movement of the rotor 124 relative to the flexible tubular member 116 causes fluid to move toward the discharge 128. Although the exemplary peristaltic pump 118 is shown with a two-headed rotor 124, various types of peristaltic pump 118 may be used (eg, a five-headed peristaltic pump). In various embodiments, the peristaltic pump 118 produces a volume controlled suction from the surgical field at the distal end 108 of the wand 102, control being based on the speed of the rotor 124, as commanded by the controller 104.

  Still referring to FIG. 1, a display device or interface device 130 may be viewed through the housing 122 of the controller 104, and in some embodiments, a user may use the interface device 130 and/or associated buttons 132 to control the controller 104. Operation mode can be selected. For example, using one or more buttons 132, the surgeon may select a low power mode that may be used to remove a portion of cartilage, an intermediate power mode that may be used to remove a meniscus, tissue. An ablation mode may be selected, such as a high power mode for large ablation and a vacuum mode for removal of loose and/or trapped tissue. The various modes of operation are described more fully below.

  In some embodiments, electrosurgical system 100 also includes a foot pedal assembly 134. The foot pedal assembly 134 may include one or more pedal devices 136 and 138, a flexible multi-conductor cable 140 and a pedal connector 142. Although only two pedal devices 136 and 138 are shown, one or more pedal devices may be implemented. The housing 122 of the controller 104 may include a corresponding connector 144 that mates with the pedal connector 142. The foot pedal assembly 134 may be used by the surgeon to control various aspects of the controller 104, such as an ablation mode. For example, the pedal device 136 may be used for on-off control of the application of radio frequency (RF) energy to the wand 102, and more specifically for energy control in the ablation mode. Further, the pedal device 138 may be used to control and/or set the ablation mode of the electrosurgical system. For example, actuation of the pedal device 138 may switch between energy levels produced by the controller 104 and the suction volume produced by the peristaltic pump 118. In particular embodiments, control of various operational or performance aspects of controller 104 may be activated by selectively depressing a finger button located on handle 110 of wand 102.

  The electrosurgical system 100 of various embodiments may have various modes of operation employing Coblation® technology. Specifically, the assignee of the present disclosure is the owner of the Coblation® technology. The Coblation® technology involves the application of a radio frequency (RF) signal between one or more active electrodes and one or more return electrodes of the wand 102 to generate a high electric field strength in the vicinity of the target tissue. The electric field strength may be sufficient to vaporize the conductive fluid over at least a portion of the one or more active electrodes in the region between the one or more active electrodes and the target tissue. The conductive fluid may be unavoidably present in the body, such as blood, or in some cases extracellular or intracellular fluids. In other embodiments, the conductive fluid may be a liquid or gas such as an electrolytic salt. In some embodiments, such as surgical procedures involving knees, shoulders, etc., the conductive fluid is delivered to the active electrode and/or near the target location by a delivery system that is separate and spaced from the system 100.

  A gas is formed when energy is applied to the conducting fluid to the point where the atoms of the fluid evaporate faster than the reaggregation of the atoms. When sufficient energy is applied to the gas, the atoms collide with each other, desorbing electrons during the process and forming an ionized gas or plasma (the so-called "fourth state of matter"). Otherwise, the plasma may be formed by heating the gas and ionizing the gas by passing an electric current through the gas or by introducing electromagnetic waves into the gas. The method of plasma formation imparts energy directly to the free electrons in the plasma, electron-atom collisions release more electrons, and the process occurs one after another until the desired degree of ionization is reached. A more complete description of plasmas can be found in [1], the complete disclosure of which is incorporated herein by reference.

If the density of the plasma is low enough (ie, less than about 1020 atoms/cm ³ for aqueous solution), the mean free path of the electrons increases, and subsequently introduced electrons cause impact ionization in the plasma. If the ionic particles in the plasma layer have sufficient energy (eg, 3.5 electron volts (eV) to 5 eV), the collision of the ionic particles with the molecules forming the target tissue will destroy the molecular bonds of the target tissue. , Decomposes molecules into free radicals, which then combine to form gas or liquid species. By molecular decomposition (as opposed to thermal evaporation or carbonization), the target tissue is where larger organic molecules become smaller molecules and/or atoms such as hydrogen, oxygen, oxides of carbon, hydrides of carbon and nitrogen compounds. , By molecular decomposition, it is removed capacitively. In contrast to dehydration of tissue material by removal of intracellular fluid or extracellular fluid of the tissue, which in the related art causes electrosurgical desiccation and evaporation, molecular degradation completely removes the tissue structure. A more detailed description of molecular degradation is set forth in US Pat. No. 6,096,849, the complete disclosure of which is incorporated herein by reference.

  The energy density produced by the electrosurgical system 100 at the distal end 108 of the wand 102 can be varied by adjusting various factors, such as the number of active electrodes, electrode size and spacing. , Electrode surface area, electrode surface roughness and/or sharp edges, electrode material, applied voltage, current limiting of one or more electrodes (eg by placing an inductor in series with the electrodes), It is the conductivity of the liquid in contact, the density of the conductive fluid and other factors. Thus, these factors are operable to control the energy level of excited electrons. Since different tissue structures have different molecular bonds, electrosurgical system 100 produces energy that is sufficient to cleave molecular bonds in certain tissues, but insufficient to cleave molecular bonds in other tissues. It may be configured to allow. For example, fatty tissue (eg, fat) has double bonds that require 4eV to greater than 5eV (ie, on the order of about 8eV) to cut. Thus, in some modes of operation, Coblation® technology is unable to ablate such fatty tissue. However, at lower energy levels, Coblation® technology can be used to effectively ablate cells to release internal fat content in liquid form. Other modes of operation may have increased energy such that double bonds may be broken as well as single bonds (eg increasing voltage or changing electrode configuration to increase current density at the electrodes). To). A more complete description of the various phenomena is set forth in commonly assigned US Pat. Nos. 5,697,697, the complete disclosures of which are incorporated herein by reference.

  The inventor will now present a theoretical basis to explain how multiple modes of operation can be implemented in a single wand 102 and a single controller 104. However, the theoretical basis is only presented as one possible explanation and should not be read as a limitation on the operation of various embodiments. It is intended that other theoretical grounds be presented equivalently and intend to describe the operation of the device using different theoretical grounds, except that such devices fall within the scope of the appended claims. Not a thing. Specifically, the electrode circuit that includes the plasma formed in relation to the active electrode of the wand, the fluid between the active electrode and the return electrode, and the electrode-fluid interface is the energy that goes from the active electrode to the return electrode. It has or exhibits a certain amount of impedance to the flow. The impedance presented by the electrode circuit can depend on many factors, such as the thickness and volume of the plasma itself, the surface area of the active electrode that is not directly covered by a layer of vapor and the plasma and the plasma in contact with the conducting fluid. Including but not limited to the volumetric flow rate of fluid and/or gas away from the location.

  In related art devices, only the vacuum pressure used for aspiration is controlled (eg the vacuum available at the wall socket connection in a hospital operating room). However, the vacuum available in a wall socket connection can vary significantly from room to room, and in many cases can vary significantly over time in the same room. Furthermore, controlling the applied vacuum pressure does not imply controlling the volume of suction. As such, related art devices may control the vacuum pressure (or identify a suitable vacuum pressure), while they do not control the volumetric flow rate of aspiration.

  By controlling the fluid flow rate at suction, rather than simply controlling the applied vacuum pressure, various modes of operation are implemented, at least in part, and in certain embodiments. In some embodiments, and as shown in FIG. 1, control of fluid flow is by a peristaltic pump 118, but other mechanisms for controlling flow, including pressure modulation, may be used equivalently. In part by controlling the fluid flow rate of the suction, the impedance in the electrode circuit can be controlled at least in part. While other parameters can also affect impedance, the inventor has found that when the volumetric flow rate of the aspirating fluid is low, it produces a larger plasma and the active electrode does not come into direct contact with the conductor flow, thus reducing the impedance of the electrode circuit. It has been found that the higher it is, and thus the less energy is dissipated, the higher the volumetric flow rate of fluid in suction, the lower the impedance and the greater the energy dissipation. Higher volumetric flow rates reduce the size of the plasma and thus increase the strength of the electric field within the plasma.

  The inventor has discovered that the relationship between aspirated fluid flow volume and energy dissipation is contrary to a dominant understanding. That is, related art devices and methods generally operate under the assumption that high flow rates propagate energy more rapidly, thus reducing the thermal aspects of ablation. In contrast, the inventor has discovered that higher volumetric volumes of suction tend to produce higher overall energy dissipation. That is, a high volumetric flow rate lowers the impedance of the electrode circuit, with lower impedance increasing energy dissipation. Furthermore, the higher volumetric flow rate causes "flicker" in the plasma. Consider the analogy in the form of candles. When the candle is burning in the room with little air movement, the flame may maintain a stable shape, size and position. However, in the presence of air flow (for example, a ceiling fan), the flame "flickers". Within the period of plasma extinction (ie plasma is absent), more energy is dissipated in the thermal mode into the surrounding fluids and tissues, and “flickering” plasma (quickly extinguished and reforming) caused by high volumetric flow rates. Plasma) causes the energy dissipation into the tissue and surrounding fluid to increase rather than decrease. That is, the “flickering” plasma will exhibit a lower average impedance, which not only results in higher energy dissipation, but also during the time the plasma is present, which is the dominant thermal mode in the momentary plasma extinction that appears in the “flickering”. Causes higher energy dissipation than.

  Thus, the embodiments described herein are designed to calculate the impedance (or impedance) at the electrodes so that the plasma field can be controlled as desired for a particular type of tissue or medical procedure. The RF current applied to the active electrode, which may be used) is monitored and used as a parameter to control the volumetric flow rate of the aspiration. For example, if the impedance at the active electrode is observed to decrease at some point during a medical procedure (which may be indicative of plasma instability), the control module of the system tells the suction pump that the plasma field is It may be instructed to reduce the suction flow rate for stability. From another perspective, it is preferable to measure the RF current applied to the active electrode and adjust the suction flow rate to maintain the current at some predetermined and desired level associated with the user's operational choices. It is possible. Further, in certain medical procedures it may be desirable to sacrifice flow rate instead of stabilizing the plasma field to reduce heat dissipation at the treatment site and to further protect the tissue. Reference is made to the assignee of US Pat. No. 5,037,009 assigned to the assignee entitled “Electrosurgical System with Aspiration Control Device, System and Method”, the complete disclosure of which is incorporated herein by reference for all purposes. Conversely, it is desirable in certain types of medical procedures to sacrifice plasma field stability to have a generally higher aspiration flow rate volume to remove bubbles and debris from the surgical field. It is possible.

  Based on the theoretical basis of the preceding paragraph, various embodiments have shown that in some embodiments using a single wand (in some cases a single active electrode) with a single controller It is directed to systems and associated methods that implement at least two modes of operation in between. In certain embodiments, a "low power mode" that may be used for the treatment and removal of vulnerable tissue, such as a portion of the cartilage of a joint, an "intermediate power" that may be used for treatment and removal of the meniscus. Four different operating modes are implemented, such as "mode", "high power mode" for strong removal of any type of tissue, and "vacuum mode" for removal of suspended and/or trapped tissue. sell. Further details regarding the exemplary modes of ablation are provided below after a discussion of the internal components of the exemplary wand 102 and controller 104.

  FIG. 2 illustrates an elevation view of wand 102 according to an exemplary system. Specifically, the wand 102 includes an elongated shaft 106, which may be flexible or rigid, a handle 110 coupled to the proximal end of the elongated shaft 106, and an electrode support 200 coupled to the distal end of the elongated shaft 106. .. Also seen in FIG. 2 is a flexible tubular member 116 extending from the wand 102 and a multi-conductor cable 112. The wand 102 includes an active electrode 202 located at the distal end 108 of the elongate shaft 106. Active electrode 202 may be coupled to an active or passive control network in controller 104 (FIG. 1) by one or more insulated electrical connectors (not shown) in multi-conductor cable 112. The active electrode 202 is electrically isolated from the common or return electrode 204, which is located on the shaft proximate to the active electrode 202 within 25 mm of the distal end, in one exemplary system, 25 mm. It Near the distal end, the return electrode 204 is concentric with the long shaft 106 of the wand 102. The support member 200 is disposed on the distal side of the return electrode 204, and may be made of an electrically insulating material such as epoxy, plastic, ceramic, silicone, glass, or the like. The support member 200 extends from the distal end 108 of the elongate shaft 106 (typically about 1 to 20 mm) and provides support for the active electrode 202.

  FIG. 3 illustrates a cross-sectional elevation view of wand 102 according to an exemplary embodiment. Specifically, wand 102 includes a suction tube portion 206 defined within elongate shaft 106. In the exemplary wand 102 of FIG. 3, the inner diameter of the long shaft 106 defines a section tube section 206, while in other cases a separate tubular section within the long shaft 106 defines a suction tube section 206. May be. The aspiration tubing 206 may be used to aspirate excess fluid, foam, tissue debris and/or ablation products from the target location near the active electrode 202. Suction tube portion 206 extends within handle 110 and is fluidly coupled to flexible tubular member 116 for coupling to peristaltic pump 118. The handle 110 also defines an internal cavity 208 in which an electrical conductor 210 resides, the electrical conductor 210 extending into the multi-conductor cable 112 and ultimately coupling to the controller 104. Similarly, conductors extend through the long shaft and couple to the return electrode 204 and the active electrode 202, respectively, but the conductor 210 resides within the long shaft 106 so as not to overly complicate the figure. Not shown as.

  FIG. 4 shows an elevation view of an exemplary active electrode (left side) with a perspective view (right side) of the distal end of wand 102, according to an exemplary system. Specifically, the active electrode 202 may be the active screen electrode 400 as shown in FIG. The screen electrode 400 may include a conductive material such as tungsten, titanium, molybdenum, or platinum. The screen electrode 400 has a diameter in the range of about 0.5 to 8 mm, in some cases about 1 to 4 mm, and about 0.05 to about 2.5 mm, in some cases about 0.1 to 1 mm. It may have a thickness. The screen electrode 400 may include a plurality of openings 402 configured to be positioned over the distal opening 404 of the suction tube section. The opening 402 is designed to allow excess fluid, bubbles and gas drawn from the ablation site to pass through and is large enough to allow ablated tissue debris to pass through the aspiration tube 206 (FIG. 3). ). As shown, the screen electrode 400 has an irregular shape that increases the ratio of edge to surface area of the screen electrode 400. A large ratio of edge to surface area results in a higher current density at the edge, and electrodes with a large surface area tend to dissipate power into the conducting medium, thus creating a screen that creates and maintains a plasma layer in the conductor fluid. This will increase the capacity of the electrode 400.

  In the exemplary embodiment shown in FIG. 4, the screen electrode 400 includes a body 406 that overlies the insulating support member 200 and the distal opening 404 to the suction tube 206. Screen electrode 400 further includes pawls 408, with five pawls 408 shown in the exemplary screen electrode 400 of FIG. The claw portion 408 may be mounted, fixed and/or embedded on the insulating support member 200. In certain embodiments, electrical connectors extend through the insulating support member 200 so that the screen electrode 400 can be secured to the insulating support member 200 and the screen electrode 400 can be electrically coupled to the controller 104 (FIG. 1). Coupled to one or more claws 408 (ie, via gluing, brazing, welding, etc.). In the exemplary system, screen electrode 400 forms a substantially planar tissue treatment surface for the smooth ablation, ablation, and ablation of meniscus, cartilage, and other tissues. In reshaping cartilage and meniscus, surgeons often desire to smooth an irregular, rough surface of tissue, leaving a substantially smooth surface. For these applications, a substantially flat screen electrode treatment surface provides the desired effect. The present specification now provides a more detailed description of controller 104.

FIG. 5 illustrates an electrical block diagram of the controller 104 according to at least some embodiments. Specifically, the controller 104 includes the processor 500. The processor 500 may be a micro-controller, so the micro-controller may be a read-only memory (ROM) 502, a random access memory (RAM) 504, a digital-analog converter (D/A) 506, an analog-digital converter ( It may be integrated with A/D) 514, digital output (D/O) 508 and digital input (D/I) 510. The processor 500 may further provide one or more externally available peripheral buses such as a serial bus (eg, I ² C), parallel bus or other bus and corresponding communication modes. The processor 500 may be further integrated with communication logic 512 so that the processor 500 can communicate with external devices such as display device 130 as well as internal devices. In some embodiments, the processor 500 may be implemented in the form of a microcontroller, while in other embodiments the processor 500 may be separate RAM, ROM, communication, A/D, D/A, D/O and D. /I device as well as communication hardware for communicating with peripherals and the like may be implemented as a stand-alone central processing unit.

  ROM 502 stores instructions executable by processor 500. Specifically, ROM 502 may include a software program that, when executed, causes the controller to implement more than one operating mode. RAM 504 may be a working memory for processor 500, in which data may be temporarily stored and from which instructions may be executed. The processor 500 may include a digital-to-analog converter 506 (eg, to an RF generator 516 in some embodiments), a digital output 508 (eg, to an RF generator 516 in some embodiments), a digital input 510 (eg, a push button switch). 132, to an interface device such as foot pedal assembly 134 (FIG. 1), and to other devices within controller 104 by communication device 512 (eg, to display device 130).

  The voltage generator 516 generates an alternating current (AC) voltage signal that is coupled to the active electrode 202 of the wand 102. In some embodiments, the voltage generator defines an active terminal 518 that couples to electrical pin 520 in connector 120 of the controller, electrical pin 522 in wand connector 114 and ultimately to active electrode 202. .. Similarly, the voltage generator defines a return terminal 524 that couples to electrical pin 526 in connector 120 of the controller, electrical pin 528 of wand connector 114 and ultimately to return electrode 204. Additional active and/or return terminals may be used. Active terminal 518 is the terminal where voltage and current are introduced by voltage generator 516, and return terminal 524 provides the return path for the current. Return terminal 524 can provide the same common or ground as the common or ground in the balance of controller 104 (eg, common 530 used for push button 132), although in other embodiments voltage generator 516 does not. From the balance of the controller 104, it may be in an electrically “floating” state, so the return terminal 524 may exhibit a voltage when measured with respect to common or earth ground (eg, common 530). However, the potential of the voltage reading at the return terminal 524 with respect to the electrically floating voltage generator 516 and thus earth ground does not invalidate the state of the return terminal of the terminal 524 with respect to the active terminal 518.

  The AC voltage signal generated and applied by the voltage generator 516 between the active terminal 518 and the return terminal 524 has a frequency of between about 5 kilohertz (kHz) and 20 megahertz (MHz) in some embodiments. However, in some cases it is between about 30 kHz and 2.5 MHz, in other cases it is between about 50 kHz and 500 kHz, usually below 350 kHz, and usually between about 100 kHz and 200 kHz. It is some RF energy. In some applications, the impedance of the target tissue is very high at 100 kHz, so frequencies around 100 kHz are useful.

  The RMS (root mean square) voltage generated by the voltage generator 516 may be in the range of about 5 volts (V) to 1800V, and in some cases about 10V to 500V, depending on the size of the active electrode. Accordingly, it may typically be between about 10V and 400V. The peak-to-peak voltage generated by the voltage generator 516 for ablation in some embodiments is in the range of 10V to 2000V, in some cases 100V to 1800V, and in other cases. Is a square wave in the range of about 28V to 1200V, usually peak-peak in the range of about 100V to 320V.

  The voltage and current generated by voltage generator 516 is compared to a laser for shallow depth necrotic tissue, where the voltage is efficiently and continuously applied (eg, pulsed at about 10 Hz to 20 Hz). , And may be supplied in a series of voltage pulses or AC voltage having a sufficiently high frequency (eg, on the order of 5 kHz to 20 MHz). Furthermore, the duty cycle of the square wave voltage generated by the voltage generator 516 (ie, the cumulative time between any first and second intervals of energy application) has a duty cycle of approximately 0.0001%. In some embodiments, on the order of about 50%, as compared to a pulsed laser that may have. Although a square wave is generated and provided in some embodiments, the AC voltage signal can be improved to include features such as voltage spikes on the rising or falling pulse of each half cycle, or the AC voltage The signal can be modified to take a particular form (eg, sinusoidal, triangular, etc.).

  The voltage generator 516 delivers an average power level in the range of a few milliwatts to a few hundreds of watts per electrode depending on the ablation mode and the state of the plasma in proximity to the active electrodes. The voltage generator 516, in combination with the processor 500, initializes the energy output of the voltage generator 516 (eg, by controlling the output voltage) based on the ablation mode selected by the surgeon and in the selected ablation mode. , Configured to vary the control to compensate for the variation caused by the use of the wand. Changes in control are discussed further below, after further discussion of peristaltic pump 118. Descriptions of various voltage generators 516 are provided in assignee's US Pat. Nos. 5,696,697 and 7, the complete disclosures of which are incorporated herein by reference for all purposes. See also, commonly assigned US Pat. No. 6,096,849 entitled "Method and System for Electrosurgical Controller with Waveform Shaping", the complete disclosure of which, even if reproduced in full below. Incorporated herein by reference.

  In some embodiments, various modes of operation implemented at least in part by voltage generator 516 may be controlled by processor 500 using digital-to-analog converter 506. For example, processor 500 may control the output voltage by providing one or more various voltages to voltage generator 516, the voltage provided by digital-to-analog converter 506 being generated by voltage generator 516. It is proportional to the voltage. In other embodiments, the processor 500 may implement one or more digital output signals from the digital output converter 508, or a communication device 512 (communication-based embodiments do not overly complicate FIG. (Not specifically shown) may be used to communicate with the voltage converter by packet-based communication.

  Still referring to FIG. 5, in some embodiments the controller 104 further includes a mechanism for sensing the current supplied to the active electrodes. In the exemplary case of FIG. 3, the sense current provided to the active electrodes may be from current sense transformer 532. Specifically, current sensing transformer 532 may have a conductor for active terminal 518 mounted through the transformer such that active terminal 518 has a single turn on the primary side. The current on the primary side of a single turn induces a corresponding voltage and/or current on the secondary side. As such, the exemplary current sensing transformer 532 is coupled to the digital-to-analog converter 514 (designated A). In some cases, the current-sensing transformer may be directly coupled to the analog-to-digital converter 514, while in other cases additional circuitry such as amplification and protection circuits may be added to the current-sensing transformer 532 and the digital-to-analog converter. 514 may be interposed. The current sensing transformer is merely illustrated as any suitable mechanism for sensing the current supplied to the active electrodes, other systems are possible. For example, a small resistor (eg, 1 ohm, 0.1 ohm) may be placed in series with the active terminal 518 and the voltage drop introduced through the resistor may be used as a current indicator. In still other cases, the current sensing circuit may measure the current in any suitable form, and the measured current value may be other than an analog signal, such as packet-based communication at communication port 512. (Not shown) so as not to complicate.

  When voltage generator 516 is in an electrically floating state, the mechanism for sensing current is not limited to active terminal 518. As such, in yet a further embodiment, the current sensing mechanism may be implemented for the return terminal 524. For example, the exemplary current sensing transformer 532 may be implemented on the conductor associated with the return terminal 524.

  In some embodiments, the single feedback parameter used only by the processor for voltage generator 516 is the amount of current. For example, in a system where the voltage generator can accurately produce the output voltage independent of the impedance of the attached load, the processor 500 having setpoint control for the voltage produced by the voltage generator 516 may be used. It may be sufficient (eg, calculate a value that indicates the impedance of the plasma in proximity to the active electrode). However, in other cases, voltage may also be a feedback parameter. As such, in some cases, active terminal 518 may be electrically coupled to digital-to-analog converter 514 (designated B). However, additional circuitry may be added between the active terminal 518 and the digital-to-analog converter 514, such as, for example, various step-down transformers, protection circuitry, and circuitry that takes into account the electrically floating nature of the voltage generator 516. It may be interposed. Such additional circuitry is not shown so as not to overly complicate the figure. In still other cases, the voltage sensing circuit may measure the voltage, and the measured voltage value may be measured by a method other than an analog signal, such as packet-based communication on communication port 512 (to make the figure too complex. May not be provided).

  Still referring to FIG. 5, the controller 104 according to various embodiments further includes a peristaltic pump 118. Peristaltic pump 118 may reside at least partially within housing 122. The peristaltic pump includes a rotor 124 mechanically coupled to the shaft of electric motor 534. In some cases, and as shown, the rotor of the electric motor may be directly coupled to the rotor 124, while in other cases various gears, pulleys and/or belts may be included in the electric motor 534. And between the rotor 124 and the rotor 124. The electric motor 534 may take any suitable form such as an AC motor, a DC motor and/or a stepper motor. The electric motor 534 may be coupled to a motor speed control circuit 536 to control the speed of the shaft of the electric motor 534 and to control the speed of the rotor 124 (and volume flow rate at the wand). In the exemplary case of an AC motor, motor speed control circuit 536 may control the voltage and frequency applied to electric motor 534. In the case of a DC motor, the motor speed control circuit 536 may control the DC voltage applied to the electric motor 534. In the case of a stepper motor, the motor speed control circuit 536 may control the current through the motor poles, but the stepper motor may have a sufficient number of poles or the rotor 124 may move smoothly. To be controlled.

  The processor 500 is coupled to the motor speed control circuit 536 (denoted by C), such as by a digital to analog converter 506. Processor 500 may be coupled by other methods such as packet-based communication on communication port 512. As such, the processor 500 executes the program to read the current supplied to the active terminal 518, read the voltage supplied to the active terminal 518, and send the speed command to the motor speed control circuit 536 accordingly. Changes in speed control (and hence changes in volumetric flow rate) may be made. The motor speed control circuit 536 then implements the speed control change. Speed control changes may include changes that change the speed of rotor 124 if desired, stop rotor 124 if desired, and in some embodiments temporarily reverse rotor 124. It should be noted that the peristaltic pump rotor 124 does not have to be rotated by an electric motor prior to processing. While electric motors can be more easily implemented in electrical control systems, other types of motors (eg, pneumatic motors) where the speed of the output shaft is controllable can be used equivalently.

  The specification now turns to a more detailed description of various modes of operation that may be implemented by an electrosurgical system. Each mode of operation is exemplary named based on the strength of the ablation. However, all exemplarily identified tissue types may be ablated in their respective and all modes, and thus providing any identification of the tissue types considered to be ablated in each mode is It should not be read as limiting the applicability of a particular mode. Ablation of tissue in a mode not specifically designed for tissue can have side effects such as discoloration of target tissue and removal of too much. The available operating modes of the system thereby provide improved performance and management of energy output coupled with control of the aspiration flow rate is dependent on the target tissue or electrosurgical procedure surgical outcome in each mode. Generate.

  According to various embodiments, the electrosurgical controller 100 includes at least two, and some, for dynamically modulating the flow rate near the active electrodes so that the output of RF energy can be adjusted. In embodiments, the following are “low power mode” that may be used for treatment, ablation and removal of a portion of cartilage, “intermediate power mode” that may be used for treatment, ablation and removal of meniscus, tissue. It implements four modes of operation: a "high power mode" that can be used for strong ablation and ablation of the tissue, and a "vacuum mode" for removal of loose and/or trapped tissue. Each exemplary mode of operation may be characterized by an initial energy setting for the voltage generator 516 and an initial volumetric flow rate setting by the peristaltic pump 118, which initial setting sets a particular desired impedance of the plasma generated during ablation. Can result in While operating in a particular mode, the energy provided by the voltage generator 516 and the volumetric flow rate provided by the peristaltic pump 118 may vary based on operating conditions at the distal end 108 of the wand. The change must not remove a condition that is within a particular mode of operation. The table below is a feature of four exemplary modes of operation at a high level.

  We will discuss each mode from now on.

  The low power mode of operation is specifically designed for the treatment and selective ablation of joint cartilage or other highly vulnerable tissues. This low power mode of operation is particularly suitable for chondroplasty and for finishing or scraping meniscus. However, the cartilage does not grow back, so in chondroplasty the amount of cartilage ablated by the surgeon is very low for most procedures. The surgeon's main concern may be to carefully remove damaged cartilage while at the same time reducing damage to the tissue of the cartilage that is left behind. For these reasons, the exemplary low power mode is characterized by low energy delivered to the active electrode along with a low volumetric flow rate of suction. Specifically, in this mode of operation it is desirable that the energy supply during the procedure maximizes cell viability and reduces instantaneous energy dissipation and heat generation in the vicinity of the treated area. For this mode of operation, reduced suction flow rates and low volumetric flow rates can result in plasma and electrode circuits with higher overall impedance.

  Vapor layer collapse and short spikes of current are prevented if possible in low power mode, so controlling the volume flow rate in low power mode is important to maintain the effectiveness and stability of the plasma. While slowing the rate (ie, slowing down the rotor 124 of the peristaltic pump 118), powerful control actions may be implemented. In some cases, the control action may be a momentary reversal of the direction of the rotor 124 of the peristaltic pump 118. Reversing the rotor of the peristaltic pump 118 would reverse the volumetric flow rate at the active electrode 202 (taking into account the elasticity of the tube 116), but nevertheless the controller 104 causes the controller 104 to generate plasma. Sensing that C is collapsing may allow the volume flow rate at the active electrode to be quickly reduced or stopped. It may be desirable to reduce the aspirated volumetric flow to near zero while the RF energy is activated in the low power mode to reduce thermal damage to surrounding tissue. The control action then provides a baseline volumetric flow rate when the RF is turned off to remove debris from the surgical field to improve visibility and to remove bubbles.

  For the voltage generator 516, the low power mode features low energy, and in some cases the controller 104 implements an upper limit on the amount of energy provided to the active electrode 202. With respect to the voltage generator 516 that produces a constant RMS voltage, the amount of current provided to the active electrode 202 may be controlled. For the voltage generator 516 controlling the voltage output, both the RMS voltage and the RMS current may be controlled to implement a low energy supply.

  In the low power mode of operation, the controller 104 controls the voltage generator 516 and the peristaltic pump 118 to implement a relatively high target impedance for the plasma and electrode circuitry to prevent plasma collapse. Control actions related to lowering the impedance (as calculated based on the current and/or voltage applied to the active electrodes) reduce the energy provided by the voltage generator 516 and slow down the peristaltic pump 118. It may be accompanied by causing and/or stopping. In some embodiments, the change in electrical energy generated by the voltage generator 516 may be implemented to be more rapid than the change in speed of the peristaltic pump 118, so in some embodiments, The initial response to the measured decrease in plasma impedance may momentarily increase the energy density delivered, followed by a reduction in pump speed and a reduction in the energy delivered.

  The intermediate power mode of operation is specifically designed for ablation of fibrocartilage tissue, such as meniscal tissue, but other types of tissue may also be ablated in the intermediate power mode. This intermediate power mode of operation may also be suitable for electrosurgical treatment of lip tissue. When ablating the meniscus, the surgeon may be interested in ablating more tissue volume than cartilage, but the resulting oxidation or "browning" of the remaining meniscus. Neither is preferable. For at least this reason, the exemplary intermediate power mode features moderate energy delivered to the active electrode, along with a moderate volume flow rate of suction to protect tissue invariance. Specifically, in this mode of operation, energy delivery during the procedure may result in changes in the tissue matrix or mechanical changes with improved protection of the tissue matrix and reduced or no tissue discoloration. Designed to prevent cross-linking of collagen tissue. A moderate volumetric flow rate can result in a plasma having a lower impedance than the low power mode, with relatively low heat dissipation in the area of treatment.

  Plasma collapse is not preferred in the intermediate power mode, but occasional plasma collapse and short current spikes may be allowed to implement a slightly stronger tissue ablation rate. Therefore, the control action on volumetric flow rate in meniscus mode may be stronger than in low power mode, and the minimum volumetric flow rate for suction may be implemented even if such a minimum leads to plasma collapse. ..

  With respect to the voltage generator 516, the intermediate power mode is characterized by slower changes corresponding to changes in the impedance of the plasma. For a voltage generator 516 that produces a constant peak voltage, the amount of current supplied to the active electrode 202 may be averaged and controlled to produce a predetermined average current. The average energy may be controlled for the voltage generator 516 controlling the voltage output.

  In the medium power operating mode, the controller 104 controls the voltage generator 516 and the peristaltic pump 118 to implement an intermediate target impedance for the plasma electrode circuit. The control action corresponding to the reduction in impedance (as calculated based on the current and/or voltage applied to the active electrodes) changes the energy delivered by the voltage generator 516 and the speed of the peristaltic pump 118. With both lowering and/or stopping. In some embodiments, the controller 104 may provide a predetermined energy, and for impedance values that fall within a predetermined range, the controller 104 may control impedance based solely on changes in the speed of the peristaltic pump 118. .. For changes in impedance that fall outside of the predetermined range, the method of control may also be based on the energy provided by voltage generator 516.

  The exemplary high power mode of operation is designed to remove tissue particularly rapidly. By way of example, this high power mode of operation may be used for acromion decompression procedures or ACL stump debridement. As such, the exemplary high power mode features high energy delivered to the active electrode along with high volumetric flow rate for aspiration. Specifically, in this mode of operation, the delivery of energy during the procedure provides tissue removal with a continuous aspiration flow volume that aspirates tissue near the wand for a more efficient ablation rate and reduced heat dissipation. Adjusted to increase. A high volumetric flow rate results in a plasma with lower impedance and constant (but uncontrolled) plasma collapse. Therefore, plasma collapse is expected to be in the high power mode, which is based on a strong suction flow, but the high power mode leads to the minimum volumetric flow rate and therefore the minimum peristaltic pump speed, which leads to plasma collapse. Also, it may be implemented.

  For the voltage generator 516, the high power mode is characterized by slower changes to changes in the impedance of the plasma. The change in energy provided to the wand electrode is slow, but upon reaching a predetermined high output energy level (eg, above 2 amps), the voltage generator 516 rapidly reduces energy or shuts off completely. May be implemented as. For a voltage generator 516 that produces a constant RMS voltage, the amount of current provided to the active electrode 202 may be controlled to be a predetermined amperage. The average output may be controlled for a voltage generator 516 that controls the voltage output.

  In the high power mode of operation, the controller 104 controls the voltage generator 516 and the peristaltic pump 118 to implement a low target impedance for the plasma. Control action in response to a decrease in impedance (as calculated based on the current and/or voltage applied to the active electrode) is accompanied by a decrease in the speed of the peristaltic pump 118, but up to a predetermined minimum volumetric flow rate. .. In some embodiments, the controller 104 may provide a predetermined energy, and for impedance values that fall within a predetermined range, the controller 104 may control the impedance based solely on changes in the speed of the peristaltic pump 118. Good. For changes in impedance that fall outside the predetermined range, control may be based on changes in the energy provided by the voltage generator 516.

  Plasma collapse is expected, but the precise timing of plasma collapse is not controlled in high power modes. In certain embodiments, the controller 104 collects or counts the amount of time the plasma is in the vicinity of the active electrode and the total time (over any suitable time period, such as 1 second). For example, the controller may assume that the plasma is present when the current is below a predetermined threshold (eg, 500 milliamps) (since there will be higher current if there is no impedance for the plasma). .. Depending on the collected time of the plasma mode, the controller 104 may take a value that indicates the “duty cycle” of the plasma versus the time without the plasma, such as by taking the time ratio of the plasma to the total time of the period. , May be decided. If the value indicated by the duty cycle indicates more than a predetermined amount of operation outside the plasma mode (eg, less than 25% of the time), then a change in control, such as reducing the suction flow rate, may be made.

  The exemplary vacuum mode of operation is specifically designed to rapidly remove airborne tissue and tissue fragments within the surgical field. Thus, the exemplary vacuum mode is characterized by the highest volumetric flow rate of the various modes (when suction is operating), as well as the various energy delivered to the active electrode. Specifically, in this mode of operation, the energy supply in the procedure is optimized for rapid fragmentation of the debris in the surgical field, with a high volumetric flow rate so that debris can be attracted to the wand tip. Designed to. A high volumetric flow rate results in a plasma with a lower impedance.

  Plasma collapse is expected in the vacuum mode, which is based on the high volumetric flow rate of the suction. In some cases, the flow rate volume will be set and maintained unchanged through the use of the mode. In other cases, the vacuum mode alternates between a maximum volume flow rate for strong tissue removal and a lower volume flow rate that allows the extinguished plasma to be "reignited", A pulse volume flow rate may be implemented. For example, in one exemplary pulsatile flow embodiment, a high volume flow rate may be implemented for 0.5 seconds and then a low volume flow rate may be implemented for 0.5 seconds. Other times are possible, such as a high flow rate in the range of 0.1 to 1.0 seconds and a low volumetric flow rate in the range of 0.1 to 1.0 seconds. Furthermore, the time of high volume flow rate and low volume flow rate need not be balanced.

  With respect to the voltage generator 516, the vacuum mode is characterized by slower changes in response to changes in the plasma and impedance of the electrode circuit. The change in energy delivered is slow, but upon reaching a predetermined high energy level (e.g., above 2 amps), the voltage generator 516 is accompanied by a rapid reduction in energy or a complete shutdown. May be implemented as. For a voltage generator 516 that produces a constant peak voltage, the amount of current provided to the active electrode 202 may be controlled to be a predetermined amperage. The average output may be controlled for a voltage generator 516 that controls the voltage output.

  In the vacuum mode of operation, the controller 104 may not change control of the operation (except implementing pulsing the aspiration flow rate). In other words, changes in the impedance of the plasma may not result in changes in the current and/or energy settings provided by the processor 500 to the voltage generator 516. In other cases, the change in energy delivery is slower than other modes of operation, with occasional drops and/or stops in energy associated with a given high energy flow rate.

  FIG. 6 relates the possible range of output RF energy to suction flow rate (shown as pump speed set point) for three exemplary operating modes: low power mode, medium power mode, and high power mode. The graph is shown. Specifically, for each mode of operation, electrosurgical controller 104 is programmed to operate within operating parameters related to output RF energy and aspiration flow rate. For example, in the "low power mode of operation" described above, the controller 104 only allows output RF energy in the range of 25 to 50 watts and a suction flow rate set point of "-1" (ie, reverse motor direction) to "5". This suction flow rate set point can in some cases range from 0 to 45 ml/min of suction flow rate. For the exemplary "intermediate output mode of operation" described above, the controller 104 may only output RF energy in the range of 50 to 150 watts and a suction flow rate of, for example, "0" (ie, peristaltic motor stopped) to "5". It may be pre-programmed to allow rate settings. For the exemplary “high power mode of operation” described above, the controller 104 is pre-programmed to allow only output RF energy in the range of 150 to 400 watts and aspiration flow rate settings of, for example, “1” to “5”. May be done.

  Each mode may be characterized by a particular energy and volumetric flow rate, but the volumetric flow rate may be initially low to help initially establish the plasma, as well as the gas phase of the fluid near the active electrode. The voltage of the applied energy may also be low to help establish Furthermore, regardless of the operating mode, when the plasma is formed at a low volume flow rate and applied voltage, the voltage and the volume flow rate can be synchronously increased to the initial set values for the operation mode. In accordance with at least some embodiments, the generated voltage 516 may include a low resistivity material (eg, blood, saline or conductive gel) that forms a lower impedance path between the return electrode and the active electrode. It is configured to limit or block current. Still further, in some embodiments, the voltage generator 516 is configured by the user to be a constant current source (ie, the output voltage changes as a function of the impedance presented at the wand 102).

The foregoing discussion is understood to be illustrative of the principles and various embodiments of the present invention. Many variations and modifications are possible. The following claims are intended to be construed to cover all such variations and modifications. For example, FIG. 6 shows that the output RF energy does not overlap between the exemplary modes of operation, but the range is merely an example. In other situations, the output RF energy of the operating mode may overlap (eg, the lower output RF energy of the intermediate output mode may overlap with the upper output RF energy of the low power mode. Therefore, the present The specification should not be construed as requiring that the various exemplary modes of operation require ranges of output RF energy that are mutually exclusive.
FIG. 7 is a block diagram and describes a method that may begin at block 700, which implements at least two modes of operation in an electrosurgical procedure and is coupled to an electrosurgical controller. Implementing a wand with a first active electrode (block 702) and controlling, at the distal end of the electrosurgical wand, the flow rate of fluid into an opening proximate the first electrode or controlling the impedance. According to (block 704) and controlling the energy delivered to the first active electrode by the electrosurgical controller or controlling the impedance (block 706). The method may then end at block 708.

  While the preferred embodiments of the present disclosure have been shown and described, modifications thereof can be made by those skilled in the art without departing from the scope and teachings of the specification. The embodiments described herein are merely illustrative and not limiting. Many various different embodiments may be made within the scope of the inventive concept, including equivalent structures, materials or methods thereof, and many modifications are detailed herein in accordance with the requirements stated in the law. It should be understood that the details herein should be construed as exemplary and not in a limiting sense, as may be practiced in the embodiments described in.

100 Electrosurgical System 102 Electrosurgical Wand 104 Electrosurgical Controller 106 Long Shaft 108 Distal End 110 Proximal End 112 Multiple Conductor Cable 114 Wand Connector 116 Tubular Member 118 Peristaltic Pump 120 Controller Connector 122 Housing 124 Rotor 126 Stator 128 Discharge Part 130 Interface device 132 Button 134 Foot pedal assembly 136, 138 Pedal device 140 Multiple conductor cable 142 Pedal connector 144 Connector 200 Electrode support 202 Active electrode 204 Return electrode 206 Suction tube part 208 Internal cavity 210 Conductor 400 Active screen electrode 402 Opening 404 Distal opening 406 Main body 408 Claw 500 Processor 502 Read only memory 504 Random access memory 506 Digital analog converter 508 Digital output 510 Digital input 512 Communication logic circuit 514 Analog digital converter 516 Voltage generator 518 Active terminal 520, 522, 526, 528 Electric pin 524 Return terminal 530 Common 532 Current sensing transformer 534 Electric motor 536 Motor speed control circuit

Claims (16)

A processor,
A memory coupled to the processor,
A voltage generator operably coupled to the processor and including an active terminal;
A wand connector configured to couple to a connector of an electrosurgical wand, the wand connector including a plurality of electrical pins, at least one electrical pin being coupled to the active terminal of the voltage generator. , Wand connector,
A peristaltic pump including a rotor coupled to an electric motor, wherein the electric motor is operably coupled to the processor.
When the memory is executed by the processor, the processor
By setting a first predetermined speed of the rotor of the peristaltic pump and a first predetermined energy supplied by the voltage generator via a first electrosurgical wand; Performing the ablation mode of
By setting a second predetermined speed of the rotor of the peristaltic pump through the first electrosurgical wand and setting a second predetermined energy supplied by the voltage generator; A second ablation mode is performed, the second predetermined speed is faster than the first predetermined speed, and the second predetermined energy is higher than the first predetermined energy . Save the program that executes the steps of performing the second ablation mode and
In each ablation mode, the program further causes the processor to:
When the impedance of the electrode circuit decreases, the flow rate of the fluid decreases.
Electrosurgical controller.   The electrosurgical controller according to claim 1, further comprising an outer housing, wherein the processor, memory, voltage generator, wand connector and electric pump are at least partially disposed within the outer housing. A first external enclosure, wherein the processor, memory, voltage generator and wand connector are at least partially disposed within the external enclosure;
A second outer casing distinguished from the first outer casing, wherein the peristaltic pump is at least partially disposed within the second outer casing; The electrosurgical controller according to claim 1, further comprising: In each ablation mode, the program further causes the processor to:
In the step of controlling the flow rate, adjusting the speed of the rotor of the peristaltic pump according to the change of the parameter indicating the impedance of the electrode circuit,
Adjusting the energy provided by the generator in response to a change in a parameter indicative of the impedance of the electrode circuit.   When the processor adjusts the speed of the rotor, the program further causes the processor to select at least one selected from the group consisting of a momentary stop of the rotor and a momentary reversal of the direction of the rotor. The electrosurgical controller according to claim 4, which executes the following.   A first ablation mode and a second ablation mode are a low power mode for use in cartilage ablation, an intermediate power mode for use in fibrocartilage ablation, and a high power mode for soft tissue ablation, respectively. And at least one ablation mode mutually exclusive from the group consisting of: and a vacuum mode for removal of free tissue.   The program further causes the processor to set a third predetermined speed of the rotor of the peristaltic pump and a third predetermined energy provided by the voltage generator to provide a third ablation. Performing a mode of execution, wherein the third predetermined speed is different from the first and second predetermined speeds, and the third predetermined energy is different from the first and second predetermined energies. The electrosurgical controller according to claim 1.   The first, second and third ablation modes each have a low power mode for use in cartilage ablation, an intermediate power mode for use in fibrocartilage ablation, and a high power mode for soft tissue ablation. The electrosurgical controller according to claim 7, wherein the electrosurgical controller is at least one ablation mode mutually exclusive of the group consisting of a mode and a vacuum mode for removal of free tissue. A processor,
A memory coupled to the processor,
A voltage generator operably coupled to the processor and including an active terminal;
A wand connector configured to be coupled to a connector of an electrosurgical wand, wherein the wand connector includes a plurality of electrical pins, the at least one electrical pin coupled to the active terminal of the voltage generator. And the wand connector,
A peristaltic pump including a rotor coupled to an electric motor operably coupled to the processor;
An electrosurgical controller including
An elongate shaft defining a proximal end and a distal end;
A first active electrode disposed at the distal end of the elongate shaft;
A connector including at least one pin electrically coupled to the first active electrode;
An electrosurgical wand including
A system including
The memory, when executed by the processor, stores a program that causes the processor to perform at least two ablation modes in the electrosurgical procedure via the electrosurgical wand, the implementation comprising: Made by the active electrode of the wand,
In each ablation mode, the program further causes the processor to:
Control the impedance of the plasma in the operating mode of the electrosurgical procedure,
In controlling the impedance of the electrode circuit, the program directs the processor to control the flow rate of fluid entering the opening at the distal end of the electrosurgical wand proximate to the first active electrode. Then, when the impedance of the electrode circuit decreases, control is executed to decrease the flow rate of the fluid ,
When the processor controls the impedance of the electrode circuit, the program causes the processor to
In a first mode of operation of an electrosurgical procedure, setting a first predetermined flow rate of the fluid and setting a first predetermined energy delivered to the first active electrode;
In a second mode of operation of the electrosurgical procedure, a second predetermined flow rate is set that is greater than a first predetermined flow rate of the fluid and is higher than the first predetermined energy. Controlling to set a second predetermined energy to be supplied to the active electrodes of the system. The program implements at least two modes, and the program causes the processor to:
The control of the impedance of the plasma in the first mode of operation of the electrosurgical procedure,
Controlling the plasma impedance in the second mode of operation of the electrosurgical procedure, wherein the plasma impedance in the second mode is different from the impedance in the first mode. The system of claim 9, wherein the system is: 10. The system of claim 9 , wherein the program causes the processor to control the speed of the rotor of the peristaltic pump as the processor controls the flow rate of fluid entering the opening. The system of claim 11 , wherein the program further causes the processor to perform a momentary reversal of the direction of the rotor of the peristaltic pump as the processor controls the speed of the rotor of the peristaltic pump. A first external enclosure, wherein the processor, memory, voltage generator and wand connector are at least partially disposed within the external enclosure;
A second outer casing, which is distinguished from the first outer casing, wherein the peristaltic pump is at least partially arranged in the second outer casing; The system of claim 9, further comprising: In each ablation mode, the program further causes the processor to
Adjustment of the speed of the rotor of the peristaltic pump in response to a change in a parameter indicating the impedance of the electrode circuit,
Adjusting the energy provided by the generator in response to a change in a parameter indicative of the impedance of the electrode circuit, the system of claim 9. When the processor adjusts the speed of the rotor, the program further causes the processor to select at least one selected from the group consisting of a momentary stop of the rotor and a momentary reversal of the direction of the rotor. 15. The system of claim 14 , which causes:   The at least two ablation modes are a low power mode for use in cartilage ablation, an intermediate power mode for use in fibrocartilage ablation, a high power mode for ablation of soft tissue, and removal of free tissue. 10. The system of claim 9, wherein the vacuum modes for and are mutually exclusive.

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