Electrosurgical instrument and electrosurgical apparatus

Abstract

Various embodiments provide an electrosurgical instrument for cutting tissue. The instrument comprises an instrument shaft including a transmission line for conveying radiofrequency electromagnetic energy. The instrument comprises a first jaw attached to the instrument shaft, including a first surface, and defining a longitudinal direction. The instrument comprises a second jaw attached to the instrument shaft and including a second surface. The instrument comprises a first electrode for emitting radiofrequency electromagnetic energy, a second electrode for emitting radiofrequency electromagnetic energy, and a third electrode for emitting radiofrequency electromagnetic energy. The instrument comprises a distal electrode for emitting radiofrequency electromagnetic energy. The instrument comprises a first isolating portion electrically isolating the first electrode from the second electrode, and a second isolating portion electrically isolating the third electrode from the first electrode, the second electrode, and the distal electrode. The first jaw and the second jaw can be moved between an open position, in which the tissue can be inserted between the first surface and the second surface, and a closed position, in which the first and second surfaces are brought together to clamp tissue therebetween. The first electrode and the second electrode are located on the first surface and within perimeters of the first surface and the second surface in the closed position such that a first radiofrequency path between the first electrode and the second electrode is contained between the first jaw and the second jaw in the closed position. The third electrode includes a distal section, the distal section being located on an outer surface of the first jaw at a distal end thereof in the closed position. The distal electrode is exposed in the closed position and configured to provide a second radiofrequency path between the distal section of the third electrode and the distal electrode. A maximal length of the first radiofrequency path is smaller than a minimal length of the second radiofrequency path.

Description

[0001] ELECTROSURGICAL INSTRUMENT AND ELECTROSURGICAL APPARATUS

[0002] FIELD OF THE INVENTION

[0003] The invention relates to an electrosurgical instrument for cutting tissue. In some examples, the electrosurgical instrument is configured to grasp biological tissue and deliver radiofrequency electromagnetic energy into the grasped tissue and to cut, e.g. separate or divide, the tissue using the applied radiofrequency electromagnetic energy. The invention may be applied to a jawed instrument for use in laparoscopic surgery or open surgery as well as to an endoscopic instrument.

[0004] The invention also relates to an electrosurgical instrument for cutting tissue which may not be a jawed instrument and includes electrodes arranged on an isolating portion.

[0005] The invention further relates to an electrosurgical apparatus for cutting tissue which comprises a generator unit for generating radiofrequency electromagnetic energy, and the electrosurgical instrument.

[0006] BACKGROUND TO THE INVENTION

[0007] Electrosurgical instruments for delivering heat energy into grasped biological tissue are known. For example, it is known to deliver microwave energy from a bipolar electrode arrangement in the jaws of a forceps. The microwave energy may be used to seal a vessel by thermal denaturation of extracellular matrix proteins (e.g. collagen) within the vessel wall. The heat energy may also cauterise the grasped tissue and facilitate coagulation.

[0008] Further, electrosurgical instruments are known which are configured to cut tissue using electromagnetic energy, for example (bipolar) radiofrequency electromagnetic energy. The cut may be applied by pressing the electrosurgical instrument against the tissue to be cut and apply the electromagnetic energy.

[0009] Such devices typically find application on the end of minimally invasive surgical laparoscopic tools but can equally find use in other clinical procedural areas such as gynaecology, endourology, gastrointestinal surgery, ENT procedures, or endoscopic procedures. Depending on the context of use, these devices can have differing physical construction, size, scale and complexity.

[0010] For example, a gastrointestinal instrument might be nominally of 3 mm diameter mounted on to the end of a very long flexible shaft. In contrast, a laparoscopic instrument may be used on the end of an industry standard nominal 5mm or 10mm diameter rigid or steerable steel shaft. US 6,585,735 describes an endoscopic bipolar forceps in which the jaws of the forceps are arranged to conduct bipolar energy through the tissue held therebetween.

[0011] EP 2 233 098 describes microwave forceps for sealing tissue in which the sealing surfaces of the jaws include one or more microwave antennas for radiating microwave energy into tissue grasped between the jaws of the forceps.

[0012] WO 2015 / 097472 describes electrosurgical forceps in which one or more pairs of non-resonant unbalanced lossy transmission line structures are arranged on the inner surface of a pair of jaws.

[0013] SUMMARY OF THE INVENTION

[0014] At its most general, the present invention provides an electrosurgical instrument that can cut biological tissue, such as (blood) vessels, using a confined radiofrequency field for enabling fine tissue cutting and / or dissection to be performed. Thereby, two spatially separated cutting functionalities are provided allowing to make two different types of cuts and / or two spatially offset cuts. With these functionalities, different types of cuts can be made which may result in fewer device interchanges during a procedure.

[0015] The electrosurgical instruments disclosed herein may be used in any type of surgical procedure, but it is expected to find particular utility for non-invasive or minimally invasive procedures. For example, the electrosurgical instrument may be configured to be introduced to a treatment site through an instrument channel of a surgical scoping device, such as a laparoscope, an endoscope, or to be introduced via a trocar, alongside a laparoscope during laparoscopic or robotic surgery.

[0016] According to a first aspect of the present invention, there is provided an electrosurgical instrument for cutting tissue which comprises an instrument shaft, a first jaw, a second jaw, a first electrode, a second electrode, third electrode, a distal electrode, a first isolating portion, and a second isolating portion. The instrument shaft comprises a transmission line for conveying radiofrequency electromagnetic energy. The first jaw is attached to the instrument shaft, includes a first surface, and defines a longitudinal direction. The second jaw is attached to the instrument shaft and includes a second surface. The first electrode, the second electrode, the third electrode, the distal electrode are each provided for emitting the radiofrequency electromagnetic energy, optionally received from the transmission line. The first isolating portion electrically isolates the first electrode from the second electrode. The second isolating portion electrically isolates the third electrode from the first electrode, the second electrode, and the distal electrode. The first jaw and the second jaw can be moved between an open position, in which the tissue can be inserted between the first surface and the second surface, and a closed position, in which the first and second surfaces are brought together to clamp tissue therebetween. The first electrode and the second electrode are exposed and / or located on the first surface (for contacting tissue) such that they (completely) are within perimeters of the first surface and the second surface in the closed position such that a first radiofrequency path between the first electrode and the second electrode is (completely) contained between the first jaw and the second jaw in the closed position. The third electrode includes a longitudinal section and / or a distal (outside) section, the distal section being exposed and / or located on an outer surface of the first jaw at a distal end of the first jaw thereof in the closed position. The distal electrode is arranged on a distal end of the first jaw so that the distal electrode is exposed and / or located (on the distal end face of the first jaw) in the closed position. The distal electrode is configured to provide a second radiofrequency path between the distal section of the third electrode and the distal electrode. A maximal length of the first radiofrequency path is smaller than a minimal length of the second radiofrequency path.

[0017] According to a second aspect of the present invention, there is provided an electrosurgical instrument for cutting tissue. The electrosurgical instrument comprises an instrument shaft, a first electrode, a second electrode, a third electrode, and an isolating portion. The instrument shaft comprises a transmission line for conveying radiofrequency electromagnetic energy. The first electrode, the second electrode, and the third electrode are each provided for emitting the radiofrequency electromagnetic energy, optionally received from the transmission line. The isolating portion is made from an electrically isolating and rigid material. The isolating portion has an upper surface, a lower surface, and a side surface connecting the upper surface to the lower surface. The first electrode, the second electrode, and the third electrode are each formed by electrically conductive layers covering the upper surface. The first electrode, the second electrode, and the third electrode each include a respective edge section that is located at or adjacent to the side surface. A maximal length of a radiofrequency path between any two edge sections of the first electrode, the second electrode, and the third electrode is smaller than a minimal length of a radiofrequency path between any two sections of the first electrode, the second electrode outside the respective edge sections.

[0018] According to a third aspect of the present invention, there is provided an electrosurgical apparatus for cutting tissue. The electrosurgical apparatus comprises a generator unit for generating radiofrequency and the electrosurgical instrument as described herein. The transmission line conveys the radiofrequency energy from the generator unit to the first electrode, the second electrode and / or the third electrode.

[0019] The electrosurgical instrument provides at least two radiofrequency paths along which current can flow through the tissue upon the application of radiofrequency electromagnetic energy. The electrodes of the electrosurgical instrument are located in such a way that the selected radiofrequency paths are in operation while no current flows along the non-selective the radiofrequency paths. This eliminates the risk that currents flow along on undesired radiofrequency paths which allows locating the applied radiofrequency paths. This may allow to locate the radiofrequency cutting at various points of the electrosurgical instrument. In this way, different radiofrequency cuts can be applied using the same instrument.

[0020] The selection of the radiofrequency path can be done by subjecting selected electrodes to the radiofrequency electromagnetic energy that is generated by the generator. This may be done using a switch or switching network and / or by applying the radiofrequency electromagnetic energy to selected lines of the transmission line.

[0021] Some electrodes of the electrosurgical instrument may be electrically connected to the same electrical line of the transmission line. This helps to reduce the number of electrical lines in the transmission and / or the diameter of transmission line. However, this has the effect that the electrode that a user does not want to be subjected to the radiofrequency electromagnetic energy is in fact powered because it is electrically coupled to an electrode that the user wants to be subjected to the radiofrequency electromagnetic energy. Due to the location, configuration, and / or shape of the electrodes of the electrosurgical instruments described herein, the electrode, that is powered due to its electrical connection to an electrode that is intended to be powered, may not form a radiofrequency path. Rather, the radiofrequency path that is subjected to the tissue is limited to the intended pair of electrodes that is powered.

[0022] In an example, the electrodes operate to provide two localised and / or spatially separated cuts of a biological vessel / tissue.

[0023] The electrosurgical instrument may also be used for vessel / tissue sealing. In this case, the transmission line may be configured to convey microwave electromagnetic energy and the electrodes may be configured to emit microwave electromagnetic energy. However, the electrosurgical instrument may include the tissue cutting functionality and may not provide the tissue sealing functionality. In other words, the electrosurgical instrument may only be configured to emit radiofrequency electromagnetic energy and not microwave electromagnetic energy.

[0024] In an example, the electrosurgical instrument may perform vessel / tissue sealing and vessel / tissue dividing. Vessel / tissue sealing is typically the application of pressure to squash the walls of a biological vessel together, followed by the application of some form of thermal energy. The thermal energy can be applied by the first to third electrodes and / or or any pair of the first to third electrode to the gripped tissue using the microwave electromagnetic energy. The pressure to the tissue can be applied by the electrodes and / or other parts of the first and second jaws. The applied electromagnetic energy disrupts / denatures the tissue cells and forms an amalgam of collagen predominant in vessel / tissue walls, which effectively bonds the vessel / tissue walls together. With time, post operatively, cellular recovery and regrowth occurs to reinforce the seal further.

[0025] Vessel / tissue dividing can be a process of cutting through a continuous biological vessel / tissue to separate it into two pieces. It is often performed after a vessel / tissue is first sealed. An alternative cutting modality is to puncture tissue and create a hole or otomy ("otomy" can be understood as any process of cutting into a part of the body) in the centre of a tissue structure. Further, other tissue cutting operations also exist, each with their own particular requirements for deployment of cutting energy.

[0026] As described above, the location of the vessel / tissue cutting provided by the first radiofrequency path is locally offset from location of the vessel / tissue cutting provided by the second radiofrequency path. Thus, differentiating between these two different types of cutting and the different control of energy required for each is an important feature of this invention.

[0027] In an example, the first radiofrequency path is completely contained within the first jaw and the second jaw in the closed position whereas the second radiofrequency path may be within and / or outside the first and second jaws in the closed position. In one example, the first radiofrequency path is used in the closed position, for example after the tissue is sealed. The second radiofrequency path may be used in an open position of the first jaw and the second jaw, for example for puncturing tissue and / or providing a gliding cut.

[0028] In the example of the electrosurgical instrument in which the electrodes each have the edge section, the different radiofrequency paths may be at spatially separated locations which may be used for confining the radiofrequency cut to different locations at the side surface. This may allow precise radiofrequency cuts since the radiofrequency path is confined to particular region of the electrosurgical instrument.

[0029] Herein, the terms “proximal” and “distal” refer to the ends of the electrosurgical instrument, the shaft, and / or the coaxial transmission line further from and closer to a treatment site respectively. Thus, in use the proximal end is closer to a generator unit for providing the RF and / or microwave energy, whereas the distal end is closer to the treatment site, i.e. the patient.

[0030] The term “conductive” is used herein to mean electrically conductive, unless the context dictates otherwise.

[0031] The term “longitudinal” used herein refers to the direction along the first jaw which, depending on the position of the first jaw (e.g. a closed position) may coincide with a direction of the instrument channel parallel to the axis of the coaxial transmission line. The term “lateral” refers to a direction that is perpendicular to the longitudinal direction. The term “inner” means radially closer to the centre (e.g. axis) of the instrument channel. The term “outer” means radially further from the centre (axis) of the instrument channel.

[0032] The term “electrosurgical” is used in relation an instrument, apparatus or tool which is used during surgery and which utilises radiofrequency (RF) electromagnetic (EM) energy and / or microwave EM energy. Herein, radiofrequency EM energy may mean a stable fixed frequency in a range 10 kHz to 300 MHz, preferably in a range from 100 kHz to 5MHz, and more preferably in a range from 360 to 440 kHz. The microwave electromagnetic energy may mean electromagnetic energy having a stable fixed frequency in the range 300 MHz to 100 GHz. The electromagnetic energy should have a frequency high enough to prevent the energy from causing nerve stimulation. In use, the magnitude of the electromagnetic energy and the duration for which it is applied may be selected to prevent the energy from causing tissue blanching or unnecessary thermal margin or damage to the tissue structure. Preferred spot frequencies for the RF EM energy include any one or more of: 100 kHz, 250 kHz, 400 kHz, 500 kHz, 1 MHz, 5 MHz. Preferred spot frequencies for the microwave EM energy include 915 MHz, 2.45 GHz, 5.8 GHz, 14.5 GHz, 24 GHz. 2.45 GHz and / or 5.8 GHz may be preferred.

[0033] The microwave electromagnetic energy and radiofrequency electromagnetic energy may be conveyed along a common signal pathway through the instrument shaft. For example, a coaxial cable may provide the common signal pathway for conveying both the microwave energy and the radiofrequency energy. In this arrangement, the transmission line may comprise an inductive filter for blocking the microwave energy from the cutting element, and a capacitive filter for blocking the radiofrequency energy from the first and second electrodes. In an alternative arrangement, the radiofrequency energy and microwave energy are conveyed along separate pathways within the instrument shaft (the transmission line includes separate pathways), wherein the inductive filter and capacitive filter are provided at a proximal end of the instrument shaft, e.g. in a handle. For example, a coaxial cable is provided for conveying the microwave electromagnetic energy while two or more wires are provided for conveying the radiofrequency electromagnetic energy.

[0034] The instrument shaft may be dimensioned to fit within an instrument channel of a surgical scoping device. The surgical scoping device may be a laparoscope or an endoscope. Surgical scoping devices are typically provided with an insertion tube that is a rigid or flexible (e.g. steerable) conduit that is introduced into a patient’s body during an invasive procedure. The insertion tube may include the instrument channel and an optical channel (e.g. for transmitting light to illuminate and / or capture images of a treatment site at the distal end of the insertion tube). The instrument channel may have a diameter suitable for receiving invasive surgical tools. The diameter of the instrument channel may be equal to or less than 13 mm, preferably equal to or less than 10 mm, and more preferably, especially for flexible insertion tubes, equal to or less than 5 mm.

[0035] The instrument shaft and the transmission line may be flexible so that they can be inserted into the instrument channel of the scoping device. Further, the transmission line may be arranged within a lumen of the shaft. The instrument shaft may cover and / or shield the transmission line. The transmission line may extend from a distal end to a proximal end of the electrosurgical instrument. In particular, the transmission line electrically connects the first electrode and the second electrode to the generator unit.

[0036] The electrosurgical instrument discussed herein may find applicability in other tissue welding techniques. For example, the energy delivery structure may be used as an alternative to staples. In some abdominal procedures, staple guns are used to deliver 50 to 100 small staples that are fired simultaneously between jaws that can have a length of 70 mm or more, or from an annular jawed arrangements with diameters of 20 to 50 mm. In this type of application multiple antenna structures such as those discussed herein may be used to cover the required length. The antenna structures may be arranged in any number of array forms to be activated simultaneously, sequentially or progressively in a suitable manner.

[0037] The first jaw and / or the second jaw may be movable relative to their instrument shaft. The first jaw and / or the second jaw may be attached to the instrument shaft via a joint or hinge. The joint may include a pivot axis around which the first jaw and / or the second jaw may rotate. The first jaw and / or the second jaw may be activated by one or more actuation rods or control wires respectively connected to the first jaw and / or the second jaw. The one or more actuation rods or control wires may extend within the instrument shaft to a proximal end of the electrosurgical instrument. The one or more actuation rods may be connected to a handle with which the first and / or second jaws can be actuated, e.g. opened and / or closed. The electrosurgical instrument comprises an actuation mechanism which converts a back-and-forth movement of the actuation rod(s) or control wire(s) in a rotational movement of the first jaw and / or the second jaw.

[0038] For example, both jaws can be movable, e.g. rotatable around a (common) pivot axle. In another embodiment, one of the jaws is fixed to the shaft and the other jaw is movable relative to the one jaw.

[0039] In the open position, the first jaw and the second jaw are (maximally) spaced apart so that there is a free space between the first surface of the first jaw and the second surface of the second jaw. In this way, tissue can be inserted between the first surface and the second surface in the open position. Usually, the first jaw and the second jaw are moved towards the tissue such that the tissue is pushed into the space between the first surface and the second surface in the open position of the first jaw and the second jaw. By moving the first jaw and / or the second jaw from the open position to the closed position, the tissue between the first surface and the second surface can be grasped and / or clamped between the first surface and the second surface. In this way, the tissue can be fixed between the first surface and the second surface in the closed position. The first surface and the second surface are the faces of the first jaw and the second jaw, respectively, that face each other in the open and / or closed position.

[0040] The pair of jaws may be pivotable relative to each other about a hinge axis that lies transverse to a longitudinal axis of the coaxial transmission line. In one example, the pair of jaws comprises a static jaw that is fixed relative to the instrument shaft, and a movable jaw that is pivotably mounted relative to the static jaw to open and close the gap between the opposing inner surfaces. The energy delivery structure may be disposed on the inner surface of the static jaw. In another example, both jaws are arranged to pivot with respect to the instrument shaft, e.g. in a symmetrical forceps-type or scissors-type arrangement. Relative movement of the pair of jaws may be controlled from a handle at a proximal end of the instrument shaft. A control rod or control wires may pass through the instrument shaft to operably couple an actuation mechanism on the handle to the pair of jaws.

[0041] In another example, the pair of jaws may be arranged to move relative to one another in a manner that maintains the inner surfaces thereof in an aligned, e.g. parallel, orientation. This configuration may be desirable for maintaining a uniform pressure on grasped tissue along the length of the jaws. One example of such a closure mechanism is disclosed in WO 2015 / 097472.

[0042] The first jaw and / or the second jaw may have a Maryland configuration. This can include that the first jaw and the second jaw are not straight but bent / curved, e.g. forming an arc or an S-shape in a top-down view or plan view.

[0043] The first surface includes the exposed sections of the first electrode, the second electrode, and / or the third electrode. The first electrode, the second electrode, the third electrode, and / or the distal electrode are arranged within and / or on the first jaw. The first electrode, the second electrode, the third electrode, and / or the distal electrode are made from an electrically conductive material, such as metal, and may be connected to the transmission line, for example an inner conductor and an outer conductor of the coaxial cable. Alternatively, first electrode, the second electrode, the third electrode, and / or the distal electrode are connected to wires of the transmission line. Optionally, two or more of the electrodes are electrically coupled to the same wire or conductor of the transmission line.

[0044] The first electrode, the second electrode, the third electrode, and / or the distal electrode include sections that are exposed such that the exposed sections are configured to contact tissue and / or to emit the radiofrequency electromagnetic energy. In other words, the exposed sections of the electrode, the second electrode, the third electrode, and / or the distal electrode are not covered by an electrical insulator and / or are configured to emit electrical currents into the tissue contacting the electrodes. The exposed sections of the electrode, the second electrode, the third electrode, and / or the distal electrode may form starting points and / or endpoints the radiofrequency paths.

[0045] The first electrode and the second electrode are electrically isolated from each other by the first isolating portion. Further, the sections of first electrode and the second electrode that are exposed on the first surface are spaced apart from each other, for example by an air gap or an exposed section of the first isolating portion.

[0046] The first electrode, the second electrode, the third electrode, and / or the distal electrode are located on the electrosurgical instrument for contacting tissue. For example, the first electrode, the second electrode, the third electrode, and / or the distal electrode each include an exposed section which is arranged and / or located for contacting tissue. The first electrode, the second electrode, the third electrode, and / or the distal electrode may each include a non-exposed section which is not configured for contacting tissue and / or may be buried or immersed in the first isolating portion and / or the second isolating portion. The non-exposed section may be provided for attaching the respective electrode to the first jaw and / or the second jaw.

[0047] The exposed sections of the first electrode and / or the second electrode may be elongate and / or extend along the longitudinal direction. The exposed sections of the first electrode and / or the second electrode optionally extend as lines and / or form areas on the first surface.

[0048] Optionally, the exposed sections of the first electrode and the second electrode may provide the first radiofrequency path along which electrical current can flow upon subjecting the first electrode and the second electrode to radiofrequency electromagnetic energy.

[0049] Any radiofrequency path described refers to the flow of an electrical current in a homogeneous tissue. In other words, a radiofrequency path relates to the routes of some field lines of the radiofrequency electromagnetic energy between respective electrodes through a homogeneous tissue. Optionally, the radiofrequency path refers to the field line having the highest strength. The radiofrequency path may be influenced by the shape and / or location of the exposed sections of the electrodes, the geometrical distance between the exposed section of the electrodes, and / or the material arranged between the exposed section of the electrodes (e.g. whether an electrical isolator is present or not or the dielectric constant of the material between the exposed section of the electrodes).

[0050] The radiofrequency path may be an alternative measure to an effective distance between the electrodes (e.g. the exposed section of the electrodes). The effective distance may be the (geometrical) distance along which the electrical current can flow during the emission of the radiofrequency energy from the electrodes (again assuming a homogeneous material of the tissue). The effective distance may be set and / or influenced by the shape and / or location of the exposed sections of the electrodes, the geometrical distance between the exposed section of the electrodes, and / or the material arranged between the exposed section of the electrodes. In other words, the minimal / maximal effective distance may be the geometrical distance measured in air between edges of the exposed sections of the respective electrodes that are closest together.

[0051] The radiofrequency path may correspond to the expected flow of electric current for cutting tissue between two electrodes that are subjected to the same radiofrequency source.

[0052] The arrangement of the electrodes such that the maximal length of the first radiofrequency path is smaller than the minimum length of the second frequency path provides that only the first frequency path is in operation for cutting tissue (i.e. an electric current is flowing through tissue) even though the electrodes involved for providing a second frequency path may also be subjected to the same radiofrequency energy. This is due to the fact that electrical currents flow along the path of least resistance. Assuming a homogeneous tissue to be cut, the intrinsic electrical resistance of the tissue is the same in the portion of the tissue along the first radiofrequency path and the second radiofrequency path. Accordingly, the electrical resistance along the first radiofrequency path and the second radiofrequency path depends on or increases with the effective distance or length of the respective frequency path. Consequently, from various potential radiofrequency paths, electric current flows only along the radiofrequency path with the short length or the shortest effective distance. In this way, a selection of the effective radiofrequency path amongst the plurality of potential radiofrequency paths can be made.

[0053] In the example described herein, cutting is effected (only) along the first radiofrequency path when the radiofrequency energy is applied to the first electrode and second electrode although the first electrode and / or the second electrode can be electrically coupled to the third electrode and / or the distal electrode. Optionally, when the first electrode and the second electrode are subjected to radiofrequency energy, cutting is only affected along the first radiofrequency path and no cutting is effected along the second radiofrequency path. This means there is no cutting of tissue between the distal electrode on the one hand and the first electrode and / or second electrode on the other hand.

[0054] In the example described herein, cutting is effected along the second radiofrequency pass when the radiofrequency energy is applied to the distal electrode and the third electrode. The exposed section of the first electrode may form a (straight) line or a straight or curved arc. The exposed section of the second electrode may form a (straight) line or a straight or curved arc which is separated by a gap from the exposed section of the first electrode. Exposed sections of the first isolating portion may be arranged between the (straight) lines of exposed sections of the first electrode and the second electrode. It is also possible that the exposed sections of the first electrode and the second electrode protrude from the first isolating portion so that an air gap may be formed between the exposed sections of the first electrode and the second electrode.

[0055] “Exposed” as described herein refers to an arrangement of the component described as “exposed” as being configured to contact tissue. In other words, exposed components and / or sections or portions thereof are configured to directly contact tissue. For example, exposed components and / or sections or portions thereof are visible by the human eye. Further, exposed electrodes and / or sections or portions thereof are configured to emit into tissue and / or receive electric currents from tissue.

[0056] The electrodes are each configured to emit radiofrequency and / or microwave energy at the exposed sections of the respective electrodes. For example, the exposed section of the first electrode may be considered an active electrode and the exposed section of the second electrode may be a return electrode for the application of radiofrequency energy. Similarly, the distal electrode may be an active electrode and the distal section of the third electrode may be a return electrode for the application of radiofrequency energy.

[0057] The greatest intensity of the emitted radiofrequency energy is achieved in a portion of the tissue that is in contact with or directly above the exposed sections of the respective electrodes. In particular, the intensity of the emitted radiofrequency energy is highest at respective edges or corners of the exposed sections of the electrodes that face each other. The radiofrequency paths extend between these sections of highest energy. Portions of the exposed sections of the first / distal electrode that are spaced apart from the respective exposed sections of the second / third electrode exhibit a (significantly) lower intensity of the emitted radiofrequency energy.

[0058] In an optional embodiment, the exposed sections of the first electrode and the second electrode at least partially extend parallel to each other and / or the exposed sections of the first electrode and the second electrode each include two straight portions that extends parallel to each other.

[0059] The exposed sections of the first electrode and the second electrode completely or partially extend parallel to each other on the first surface. The exposed section of the first electrode may completely or partially extend parallel to the exposed section of the second electrode. The geometrical distance between the straight portions of the exposed sections may set the maximal effective distance between the first and second electrodes and / or the maximal length of the first radiofrequency path.

[0060] The first electrode and the second electrode are electrically isolated from each other by the first isolating portion. Further, the sections of the first electrode and the second electrode that are exposed on the first surface are spaced apart from each other, for example by an air gap or the first isolating portion (e.g. an exposed section thereof).

[0061] The first surface and a distal end face of the first jaw may form a continuous surface of the first jaw. The first surface and the distal end face may be inclined relative to each other. For example, an angle between a plane defined by the first surface and a plane defined by the distal end face may form an angle between 10° to 90°, optionally 45°, 60°, or 90°. The distal end face, the first surface, and an outer surface of the first jaw may form a continuous surface of the first jaw. The distal end face may be a surface of the first jaw that is arranged at a most distal position of the first jaw. In other words, when moving the first jaw along the longitudinal direction of the first jaw towards the tissue, the distal end face firstly and / or solely contacts the tissue.

[0062] The distal end face may be straight / flat. Alternatively, the distal end face may be curved. The sections of the third electrode, the distal electrode, the first isolating portion, and / or the second isolating portion that are exposed at the distal end face may be flush with respect to each other or define a flat or smooth surface. Alternatively, the sections of the third electrode and / or the distal electrode that are exposed at the distal end face may protrude from the distal end face.

[0063] The outer surface and the distal end face may form the surfaces of the first jaw that are exposed in the closed position.

[0064] In an optional embodiment, the third electrode further includes a longitudinal section extending along the longitudinal direction.

[0065] The longitudinal section of the third electrode may be exposed on the first surface or on the outer surface of the first jaw. The longitudinal section of the third electrode may form a return electrode for a third radiofrequency path for which the combined first electrode and the second electrode form an active electrode. Thus, in this example, the first electrode is electrically coupled to the second electrode for applying the third radiofrequency path.

[0066] The minimal length of the third radiofrequency path or minimal effective distance between the exposed section of the longitudinal section of the third electrode on the one hand and the exposed sections of the first electrode and / or the second electrode may be larger than the maximal length of the first radiofrequency path or the maximum effective distance between the first electrode and the second electrode. This may help to confine the first radiofrequency path between the first jaw and the second jaw in the closed position.

[0067] The longitudinal section may include two exposed sections on either side of the first electrode and / or the second electrode. Thus, the third radiofrequency pathway may extend from the first electrode and / or the second electrode to either side (e.g. in a lateral direction) towards the exposed sections of the longitudinal section of the third electrode.

[0068] The distal electrode can be arranged or located on the distal end face of the first jaw. The distal electrode may protrude from the distal end face. Alternatively, the distal electrode does not protrude from a distal end face may be flush with the distal end face. However, the distal electrode is exposed on the distal end face.

[0069] The distal section of the third electrode may also be arranged or located on a distal end face of the first jaw. The distal section may be flush with the distal end face. The distal section of the third electrode and the distal electrode may be spatially separated from each other. The second isolating portion may be arranged between the distal section of the third electrode and the distal electrode. The second isolating portion may be flush with the distal end face and / or exposed on the first surface.

[0070] The exposed portion of the distal section of the third electrode may extend around the distal electrode. For example, the distal electrode is a centre around which the exposed portion of the distal section of the third electrode extends, for example in a semicircle. The exposed portion of the distal section of the third electrode may extend from an edge with the first surface on a first side around the distal electrode to an edge with the first surface on a second side.

[0071] The effective distance between the edge of the exposed portion of the distal section of the third electrode and the distal electrode may be constant along the extension of the exposed portion on the distal section of the third electrode. In this case, there is no preferential direction of the second radiofrequency path. Rather, the second radiofrequency path starts from the distal electrode to any exposed portion of the distal section of the third electrode.

[0072] The second radiofrequency path is not contained between the first jaw and the second jaw in the closed position because the distal section of the third electrode and the distal electrode are exposed on the distal end face which is exposed even if the first jaw and the second jaw are in the closed position.

[0073] The second radiofrequency path may be used for effecting tissue cutting at the distal end face of the first jaw. This may be helpful for puncturing tissue. Tissue cutting using the second radiofrequency path may be effected in the closed position and / or the open position.

[0074] The exposed sections of the first electrode and / or the second electrode are arranged or located in such a way that, in the closed position, no portion of the first electrode and the second electrode is exposed e.g. for contacting tissue. Rather, in the closed position, the first electrode and the second electrode are (completely) retained or contained between the first jaw and the second jaw and / or between the first surface and the second surface. To this end, the exposed sections of the first electrode and the second electrode may lie within the perimeters of the first jaw and / or the second jaw in the closed position.

[0075] The perimeter of the first surface may be an edge between the first surface on the one hand and the outer surface and the distal end face of the first jaw on the other hand. The perimeter of the second surface may be an edge between the second surface the one hand and an outer surface and a distal end face of the second jaw on the other hand.

[0076] In other words, the first electrode and the second electrode are (completely) retained within borders or boundaries of the first surface and the second surfaces in the closed position. The first electrode and the second electrode may not be exposed at the distal end face.

[0077] In this way, the radiofrequency energy can be contained between the first jaw and the second jaw in the closed position when radiofrequency energy is applied between the first electrode and the second electrode. This may help to confine radiofrequency cutting between the first electrode and the second electrode.

[0078] Radiofrequency cutting along the first radiofrequency path may be used for cutting tissue clamped between the first jaw and the second jaw. It has been found that radiofrequency cutting along the second radiofrequency path and / or the third radiofrequency path is more effective compared to radiofrequency cutting along the first radiofrequency path up to a point where tissue becomes dry or is dried out. In this case, the additional clamping pressure in the closed position as well as the short effective distance between the first electrode and the second electrode may provide effective radiofrequency cutting even with dry tissue. Thus, radiofrequency cutting along the first radiofrequency path may be used for dry or dried out tissue, for example for tissue for which radiofrequency cutting along the second and / or third radiofrequency path is no longer effective.

[0079] The second jaw may partially or completely cover the first surface in the closed position of the first jaw and the second jaw. In any case, the second jaw may cover - in the closed position - the sections of the first electrode and the second electrode that are exposed on the first surface. Stated differently, if the first jaw and the second jaw are brought together with no tissue therebetween, the second jaw covers and / or contacts the sections of the first electrode and the second electrode that are exposed on the first surface. In this way, the second jaw may function to shield the first and / or second electrode(s) when the jaws are closed.

[0080] Optionally the second jaw does not cover the distal end face in the closed position of the first jaw and the second jaw. The first isolating portion and / or the second isolating portion may be made from an electrically non-conductive material such as a ceramic (e.g. Zirconia), plastic material (e.g. Polyetheretherketon (PEEK)), and / or silicone.

[0081] In an optional embodiment, the distal electrode is electrically coupled to the second electrode.

[0082] In this case, the second electrode and the distal electrode may form a common electrode. In another words, the distal electrode and the second electrode may be subjected to the same radiofrequency energy. Thus, when applying radiofrequency energy to the second electrode (for example for effecting tissue cutting along the first radiofrequency path), the distal electrode is subjected to the same electromagnetic potential. However, the radiofrequency electromagnetic energy is emitted (entirely) along the first radiofrequency path and not along the second radiofrequency path due to the arrangement of the electrodes as described above. Thus, even if the distal electrode is electrically coupled to the second electrode and exposed in the closed position of the jaws, the emitted radiofrequency energy is confined between the first jaw and the second jaw in the closed position.

[0083] In an optional embodiment, the second electrode extends beyond the first electrode in the longitudinal direction towards the distal end of the first jaw. Optionally the distal electrode is connected to a distal end of the second electrode.

[0084] The exposed section of the second electrode may extend beyond the exposed section of the first electrode in a longitudinal direction towards the distal end face of the first jaw. In other words, the exposed section of the second electrode may be longer than the exposed section of the first electrode. A distal end of the first electrode (e.g. of the exposed section thereof) may be spaced from and / or offset to the distal end face.

[0085] The distal electrode may be integrally formed with the second electrode. The section of the second electrode that is longer than the first electrode may form the connection of the distal electrode to the rest of the second electrode.

[0086] The maximal distance between the exposed longitudinal sections of the first electrode and the second electrode may be smaller than the distance between a distal end of the first electrode and the distal electrode. In this way, the configuration of the first radiofrequency path and the second radiofrequency path can be implemented.

[0087] In an optional embodiment, the first electrode and the second electrode are separated by a gap having a width perpendicular to the longitudinal direction. Optionally, the distal electrode has a breadth perpendicular to the longitudinal direction, the breadth being equal to or greater than the width of the gap.

[0088] The width of the gap may be equal to the effective distance between the first electrode and the second electrode. The first electrode and / or the second electrode may have the shape of a rod or an elongate plank. The distal electrode may have the shape of a cuboid, pyramid, or a cone. These shapes may have curved and / or rounded external surfaces and / or a pointed tip in order to limit accidental mechanical damage to tissue and also to control energy concentration when used as a single exposed electrode. The distal electrode may protrude from the distal end face or may be flush with the distal end face, irrespective of the shape of the distal electrode.

[0089] The breadth of the distal electrode may correspond to a width of the cuboid, a width of the ground face of the pyramid, or a diameter of the ground face of the cone.

[0090] A breadth of the distal electrode measured in a lateral direction perpendicular to the longitudinal direction may have to same breadth of the first electrode and the second electrode combined. In other words, the structure including the first electrode, the second electrode, and the distal electrode may have a constant breadth along the longitudinal direction except for a cutout between the distal end of the first electrode and a proximal end of the distal electrode. Stated differently, where the first electrode and the second electrode form a gap therebetween, the corresponding gap is filled with electrode material with the distal electrode.

[0091] It is also possible that a breadth of the distal electrode is larger than the breadth of the combined structure of the first electrode and the second electrode, especially the exposed sections thereof.

[0092] In an optional embodiment, the longitudinal section of the third electrode includes two surface sections exposed on the first surface and / or second surface. Optionally, the first electrode and the second electrode extend between the two surface sections of the third electrode in the closed position.

[0093] The surface sections of the third electrodes may correspond to the exposed sections of the longitudinal section of the third electrode described above. Thus, the surface sections may form a return electrode for the third radiofrequency path and the combined first electrode and the second electrode form an active electrode for the third radiofrequency path.

[0094] When the distal electrode is electrically coupled to the second electrode, the second radiofrequency path and the third radiofrequency path are activated at the same time. The second and third radiofrequency paths may be used for providing a gliding cut whereby the first jaw is pressed against tissue resulting in a tissue cut along the longitudinal direction of the first jaw and the distal end face. As described above, the pressure of the tissue against the first jaw may be limited as the electrosurgical instrument may be in the open position. Thus, with desiccated or dry tissue, such a gliding cut may not be longer possible. In this case, a cut using the first radiofrequency path may be used whereby the tissue is clamped between the first jaw and the second jaw.

[0095] The gliding cut may be similarly used compared to a mechanical blade that is arranged on the first surface and the distal end face. The arrangement of the surface section of the first electrode on the first surface provides a relatively short distance between the surface sections and the first and second electrodes which is considered to enhance the cutting efficiency along the third radiofrequency path.

[0096] The surface sections may be arranged on the first surface. In this case, the electrode and the second electrode extend between the two surface sections of the third electrode in the open and the closed positions. In an alternative example, the surface sections may be arranged on the second surface. In this case, the electrode and the second electrode extend between the two surface sections of the third electrode only in the closed position.

[0097] The surface sections may cover a larger area compared to the exposed sections of the first electrode and / or the second electrode. It is also possible that the third electrode only includes a single surface section which may extend parallel to the first electrode and the second electrode. In case there are two surface sections, the surface section may be mirror with regard to the first electrode and the second electrode.

[0098] In an optional embodiment, the surface sections of the third electrode are integrally formed with the distal section of the third electrode.

[0099] In this case, the surface sections and the distal section may form exposed sections of the third electrode which may be a solid or Unitarian component. The distal section may extend from the distal end of the first surface section to the distal end of the second surface section. For example, the surface sections and the distal section form a continuous exposed portion of the third electrode, e.g. a loop on the first surface and the distal end face.

[0100] A breadth or width of the surface section (measured perpendicular to the longitudinal direction) may be equal to a breadth or width of the distal section.

[0101] In an optional embodiment, the third electrode forms a solid element including an elongate recess. Optionally the first isolating portion and the second isolating portion are arranged in the elongate recess forming a unitary isolating portion. Further optionally, the first electrode, the second electrode, and the distal electrode are arranged within and / or on the unitary isolating portion.

[0102] The solid element of the third electrode may provide structural rigidness and / or stability of the first jaw. The solid element of the third electrode may also provide the outer surface of the first jaw. The solid element may be a unitary component. The solid element may be free from cavities or, if cavities are provided within the solid element, these cavities do not affect the stability and / or rigidness of the third electrode. The solid element may form a block or solid structure made from an electrically conductive material.

[0103] The recess may extend along the longitudinal direction of the first jaw. The elongate recess may be arranged in the centre with regard to the lateral direction of the first jaw. The elongate recess may extend from a proximal end of the first jaw to a distal end of the first jaw. The elongate recess may be open at the distal end face of the first jaw. The elongate recess may be open on the first surface.

[0104] The elongate recess may be partially or fully filled by the unitary isolating portion. The first electrode and the second electrode may be arranged within and / or on the unitary isolating portion. For example, the exposed sections of the first electrode and the second electrode are arranged protruding from the unitary isolating portion. A section of the unitary isolating portion may be arranged between the first electrode and the second electrode. This section may correspond to the first isolating portion. A further section of the unitary isolating portion may be arranged between the surface of the elongate recess and sections of the first electrode and / or the second electrode that are immersed in the unitary isolating portion. This further section may correspond to the second isolating portion.

[0105] As the unitary isolating portion is (only) arranged within the elongate recess, sections of the third electrode or the solid element are exposed on the first surface. These sections may form the longitudinal section of the third electrode.

[0106] The unitary isolating portion electrically isolates the first electrode and the second electrode from the third electrode. Further, the unitary isolating portion may support the first electrode and / or the second electrode on the third electrode. For example, the first electrode and / or the second electrode may be fixed to the first jaw, for example to the third electrode, solely via the unitary isolating portion. The unitary isolating portion may be made from silicone. The unitary isolating portion is therefore attached to the third electrode, first electrode, and / or the second electrode, for example via an adhesive, interlocking, and / or fastening means.

[0107] The distal electrode may extend beyond the unitary isolating portion in the longitudinal direction at a distal end face. As described above, the distal electrode may be attached to the second electrode, e.g. forming a unitary component. In this case, the distal electrode is also supported by the unitary isolating portion via the second electrode. The unitary isolating portion may be exposed at the distal end face which provides the electrical isolation between the third electrode and the distal electrode at the distal end face.

[0108] In an optional embodiment, the electrosurgical device further comprises a third isolating portion covering at least a section of an outer surface of the third electrode and / or the distal end face being otherwise exposed in the closed position. Optionally, the third isolating portion forms a gap with the second isolating portion on the outer surface and / or the distal end face so that an area of the third electrode is exposed on the outer surface and / or the distal end face.

[0109] The third isolating portion may be made from the same material as the first isolating portion, the second isolating portion, and / or the unitary isolating portion. The third isolating portion covers at least a section of the outer surface of the third electrode which may correspond to the outer surface and / or distal end face of the third electrode. The third isolating portion covers at least a section of the distal end face. The cover of the outer surface by the third isolating portion may reduce the friction between the outer surface of the first jaw and the tissue, for example if a nonstick material such as silicone is used. Further, the third isolating portion may provide that sections of the outer surface of the third electrode and / or the first jaw do not participate in the radiofrequency cutting because they are covered by the electrically nonconductive third isolating portion.

[0110] This effect may be used on the distal end face in that the second isolating portion or the unitary isolating portion in combination with the third isolating portion may define the area of the third electrode that is exposed on the distal end face. This can help to shape the second radiofrequency path. For example, the third isolating portion can be used to provide the curved distal section of the third electrode as described above.

[0111] In an optional embodiment, the third electrode includes a solid element having an inner surface facing the second jaw in the closed position and an outer surface exposed in the closed position. Optionally, the second isolating portion covers the inner surface, optionally the entire inner surface.

[0112] The optional features, characteristics and / or embodiments of the solid element of the optional embodiment described above may equally apply to the solid element of this optional embodiment, except for the differences are outlined below.

[0113] The solid element may have a flat inner surface. In other words, in this embodiment, the solid element may be free of the recess described above. Instead, the inner surface of the third electrode and / or of the solid element may be covered (entirely) by the second isolating portion. The second isolating portion may (entirely) provide the first surface. It is possible that the third electrode is not exposed on the first surface - in contrast to the embodiment described above.

[0114] The second isolating portion may provide a layer on the inner surface which correspond to the surface of the third electrode that faces the second surface in the closed position. Thus, the inner surface of the third electrode may extend along or parallel to the first surface, for example if the second isolating portion has a constant thickness.

[0115] The third electrode may be exposed for contacting tissue on the outer surface of the first jaw and / or the third electrode, unless it is covered by the third isolating portion. To be clear, the third electrode of this embodiment may also include the first isolating portion as described above. The third electrode may be exposed for contacting tissue on the distal end face of the first jaw.

[0116] The third radiofrequency path may extend from the first electrode and / or the second electrode to the outer surface of the first jaw or the third electrode, for example the outside side surface. Thus, portions of the outer surface of the third electrode may form the longitudinal section of the third electrode.

[0117] In an optional embodiment, the first electrode and the second electrode are arranged in and / or on the second isolating portion.

[0118] The first electrode and the second electrode may be arranged within and / or on the second isolating portion. For example, the exposed sections of the first electrode and the second electrode are arranged protruding from the second isolating portion. A section of the second isolating portion may be arranged between the first electrode and the second electrode. This section may form a portion of the first isolating portion. Another section of the first isolating portion may be arranged between the first electrode and the second electrode such that the first isolating portion is flush with the exposed sections of the first electrode and / or the second electrode.

[0119] The first isolating portion and the second isolating portion may be integrally formed. For example, the first isolating portion and the second isolating portion form the unitary isolating portion as described above and / or may form virtual compartments of this unitary isolating portion.

[0120] The second isolating portion electrically isolates the first electrode and the second electrode from the third electrode. Further, the second isolating portion may support the first electrode and / or the second electrode on the third electrode. For example, the first electrode and / or the second electrode may be fixed to the first jaw, for example to the third electrode, solely via the second isolating portion. The second isolating portion may be made from silicone. The second isolating portion is therefore attached to the third electrode, first electrode, and / or the second electrode, for example via an adhesive, interlocking, and / or fastening means.

[0121] The distal electrode may extend beyond the second isolating portion in the longitudinal direction at a distal end face. As described above, the distal electrode may be attached to the second component with the second electrode. In this case, the distal electrode is also supported by the second isolating portion via the second electrode. The second isolating portion may be exposed at the distal end face which provides the electrical isolation between the third electrode and the distal electrode at the distal end face. In this case, the distal section of the third electrode may not be curved at the distal end face if the second isolating portion has a constant thickness. Rather, the distance between the distal electrode and the distal section of the third electrode varies along the lateral direction.

[0122] In the above-described embodiments, the first electrode, the second electrode, and / or the distal electrode can be rigid element made from an electrically conductive material. For example, the first electrode and / or the second electrode are sufficiently rigid such that they are not deformed when tissue is clamped between the first jaw and the second jaw, i.e. when the tissue presses on the first electrode and / or the second electrode.

[0123] The first electrode, the second electrode, and / or the distal electrode may “float” on the first isolating portion and / or the second isolating portion. This means that the first electrode, the second electrode, and / or the distal electrode may move when pressure is applied to the electrodes, for example when tissue is clamped between the first jaw and the second jaw. The movement of the first electrode, the second electrode, and / or the distal electrode may be due to a compression of the first isolating portion and / or the second isolating portion. In other words, the first electrode, the second electrode, and / or the distal electrode may be movably attached to the first jaw, optionally relative to the third electrode.

[0124] In an optional embodiment, the first electrode, the second electrode and the distal electrode are electrically conductive layers on a rigid isolator forming the first isolating portion.

[0125] The rigid isolator may be made from an electrically nonconductive material that is sufficiently rigid such that it is not deformed when tissue is clamped between the first jaw and the second jaw, i.e. when the tissue presses against the rigid isolator. For example, the rigid isolator is made from a ceramic material.

[0126] The rigid isolator may be arranged on and / or fixed to the second isolating portion. For example, the rigid isolator is arranged in the elongate recess described above or on the second isolating portion covering the inner surface. In these cases, the first isolating portion and the second isolating portion may not be integrally form. However, it is also possible that the first isolating portion and the second isolating portion are integrally formed. This means that the second isolating portion is also made from a rigid isolating material.

[0127] An optional difference to the embodiments described above is that the first electrode, the second electrode, and / or the distal electrode are not a rigid element and rather are formed by layers of electrically conductive material that are applied to the rigid isolator, for example the first isolating portion. For example, two spatially separated layers cover sections of the rigid isolator. A first layer may form the first electrode and a second layer may form the second electrode as well as the distal electrode.

[0128] In an example, the rigid isolator may be elongate, extends in the longitudinal direction, and / or have a rectangular or square shape in a cross-sectional view. A first side of the rigid isolator may be exposed for contacting tissue and / or may extend approximately parallel to the first surface and / or the second isolating portion. The first electrode may cover a second side of the rigid isolator adjacent to the first side. The second electrode may cover a third side of the rigid isolator adjacent to the first side and opposing the second side. Thus, a width of the first side measured in the lateral direction may correspond to the length of the first radiofrequency path. The distal electrode may be formed by an electrically conductive layer that is arranged on a distal end portion of the rigid isolator and covers the first side, the second side, the third side, a forth side (opposing the first side) and / or a distal end face of the rigid isolator. For example, the electrically conductive layer forming the distal electrode is arranged on that portion of the rigid isolator that extends beyond the distal end face of the first jaw. Optionally, all side surface of the rigid isolator that are exposed on the distal end face are covered with the electrically conductive layer. The electrically conductive layer forming the first electrode may terminate forming a gap with the electrically conductive layer forming the distal electrode for forming the second radiofrequency path.

[0129] In an optional embodiment, the longitudinal section of the third electrode is arranged on the second isolating portion or arranged exposed on the second surface.

[0130] The third electrode may include two longitudinal sections arranged on either side of the first electrode and the second electrode (in the closed position) as described above.

[0131] The one or more longitudinal sections are for example arranged on the second isolating portion that forms a layer on the flat inner surface of the solid element of the third electrode (e.g. the recess free solid element as described above). In this case, the longitudinal section(s) are not integrally formed with the solid element of the third electrode. Rather, the longitudinal section(s) are spatially separated from the solid element of the third electrode by the second isolating portion. The longitudinal section(s) may be mechanically supported by the second isolating portion. For example, the longitudinal section(s) may float on the second isolating portion. The first electrode and / or the second electrode may also float on the second isolating portion.

[0132] Silicone is more flexible and softer compared to other types of electrically isolating material. This may reduce the pressure applied to the tissue between the radiofrequency electrode and the second isolating portion in the closed position. It has been found that radiofrequency cutting is more effective if less pressure is applied during microwave sealing. The reduction of pressure may be achieved by the provision of the isolating portions made from silicone.

[0133] The second jaw may include a fourth electrode which may be mirror- symmetric to the third electrode in the closed position. The second jaw may also include a fourth isolating portion which electrically isolates the first electrode, the second electrode, the distal electrode, and / or the third electrode from the fourth electrode in the closed position and / or the open position. The fourth isolating portion may have to same optional embodiments, characteristics, and / or features as the first isolating portion, the second isolating portion, and / or the third isolating portion.

[0134] In an example, the fourth electrode may include a solid element that is mirror- symmetric to the solid element of the third electrode in the closed position and / or the fourth isolating portion is mirror-symmetric to the second isolating portion in the closed position. For example, the solid element of the fourth electrode may also include an inner surface that faces the first surface in the closed position, wherein the inner surface is covered by the fourth isolating portion.

[0135] The longitudinal section(s) of the third electrode may be arranged on the fourth isolating portion such that they arranged on the side or on either side, respectively, of the first electrode and the second electrode in the closed position. In this example, the third radiofrequency path extends between the first jaw and the second jaw. However, there might be only a slight difference between the arrangement of the longitudinal section on the second isolating portion described above compared to the arrangement of the longitudinal section on the fourth isolating portion because, in the closed position, the respective locations of the longitudinal section(s) can be approximately the same.

[0136] When applying microwave radiation, the first electrode, the second electrode, and / or the distal electrode may form an active electrode for the emission microwave radiation, and the third electrode may form a counter electrode for the emission microwave radiation. For example, the first electrode, the second electrode, and / or the distal electrode may be connected to an inner conductor of a coaxial cable and the third electrode is connected to an outer conductor of the coaxial cable.

[0137] The second jaw may include one, two, or more electrodes (e.g. the fourth electrode and a fifth electrode) which may be provided for the emission of radiofrequency and / or microwave radiation. For example, the electrodes of the second jaw are arranged mirror-symmetric to the electrodes of first jaw. The electrodes of the second jaw may provide an active electrode and a counter electrode for the emission microwave radiation. For example, the electrodes of the second jaw may be respectively connected to the inner conductor and the outer conductor of the coaxial cable.

[0138] In an alternative embodiment, the electrodes of the second jaw are grounded. It has been found that the grounded electrodes of the second jaw balance the emission of microwave energy by the electrodes of the first jaw such that a more uniform emission distribution along the axial direction of the first jaw and / or the second jaw can be provided.

[0139] In these examples, the third radiofrequency path may extend along the first surface and / or the second surface. For example, the third radiofrequency path may be within the perimeter of the first surface and / or the second surface. In other words, in the closed position, the third radiofrequency path may also be contained between the first jaw and the second jaw.

[0140] This configuration of the second jaw may also be used with other embodiments of the first jaw described herein. More generally, the second jaw may include one or more electrodes (e.g. the fourth electrode) that are electrically isolated from the electrodes on the first jaw in the closed position and / or the open position. For example, the fourth isolating portion is provided to electrically isolate the first electrode, the second electrode, and / or the distal electrode from the electrode arranged on the second jaw. The fourth isolating portion may cover the entire second surface. The fourth isolating portion may be made from the same material as the first isolating portion, the second isolating portion, and / or the third isolating portion.

[0141] In an optional embodiment, the outer surface of the third electrode forms the longitudinal section of the third electrode.

[0142] With this embodiment, there may be no portion of the third electrode exposed on the first surface and / or the second surface. In other words, the first surface and / or the second surface may be free from the third electrode. Instead, sections of the third electrode outside the first surface and / or the second surface may form the longitudinal section(s). For example, sections on the outer surface (for example of the solid element) that extend along the longitudinal direction and / or parallel to a side of the second isolating portion may form the longitudinal section(s). In this case, the third radiofrequency path extends from the first electrode and / or the second electrode along the first surface towards the outer surface of the third electrode and / or the first jaw. In this case, the third radiofrequency path may extend beyond the first surface. In other words, in the closed position, the third radiofrequency path may not be contained between the first jaw and the second jaw.

[0143] The breadth and / or the length of the longitudinal section(s) can be formed by the third isolating portion. For example, the third isolating portion may form a gap with the second isolating portion on the outer surface for providing the longitudinal section(s). The third isolating portion may not contact the second isolating portion on the outer surface. In other words, a gap is formed between the second isolating portion and the third isolating portion along which the third electrode is exposed for forming the longitudinal section(s).

[0144] In an optional embodiment, the first isolating portion, the second isolating portion, the third isolating portion, and / or the fourth isolating portion are made from silicone.

[0145] In an optional embodiment, a rigid and unitary isolator forms the first isolating portion and the second isolating portion. Optionally, the isolator includes an upper surface forming sections of the first surface and a lower surface facing away from the first surface. Further optionally, electrically conductive layers are arranged on the upper surface forming the first electrode, the second electrode, the third electrode, and the distal electrode. In some examples, at least a distal edge region of the lower surface is covered by an electrically conductive layer which forms a portion of the third electrode.

[0146] The rigid and unitary isolator may be made from a ceramic material. The isolator may be sufficiently rigid such that it is not deformed if tissue is clamped between the first jaw and the second jaw. The isolator may have a flat body and / or may correspond in its shape to the second isolating portion that is arranged on the inner surface of the solid element of the first electrode (e.g. the recess-free configuration). For example, the isolator is attached to the inner surface of the solid element of the first electrode.

[0147] The isolator and / or the flat body of the isolator has the upper surface, the lower surface, and / or a side surface which connects the upper surface to the lower surface. The upper surface may provide the (entire) inner surface of the first jaw. The outer surface may be attached to the inner surface of the solid element of the first electrode. The side surface may form a portion of the outer surface of the first jaw, e.g. of the distal end face.

[0148] The electrically conductive layers can be formed on the upper surface and / or the lower surface. The side surface may be free from electrically conductive layers.

[0149] The electrically conductive layers on the upper surface may extend at least partially parallel to each other for forming the first electrode, the second electrode, and / or the third electrode. The electrically conductive layer forming the second electrode may extend beyond the electrically conductive layer forming the first electrode towards the distal end of the first jaw. The distal electrode may be a section at the distal end portion of the upper surface that is covered with an electrically conductive layer. This electrically conductive layer may be integrally formed with the electrically conductive layer that forms the second electrode.

[0150] The electrically conductive layer forming the distal electrode may extend until an edge between the upper surface and the side surface such that this electrically conductive layer is exposed in the closed position of the first jaw and the second jaw. In this embodiment, the distal electrode may not extend beyond the distal end face of the first jaw and / or is flush with distal end face of the first jaw.

[0151] The electrically conductive layer forming the third electrode may extend along and / or in contact with a side edge of the isolator between the upper surface and the side surface.

[0152] The lower surface may be (entirely) covered by an electrically conductive layer. This electrically conductive layer may be in contact with the inner surface of the solid element of the third electrode. Thus, the third electrode of this embodiment includes the solid element and electrically conductive layers on the upper surface and the lower surface. In other words, the electrically conductive layer forming the third electrode and the solid element are on the same electrical potential and / or electrically coupled to each other. For example, the isolator may include through holes extending between the upper surface and the lower surface for connecting the electrically conductive layer on the inner isolated face to the electrically conductive layer on the lower surface. The electrically conductive layer on the lower surface forming the third electrode may extend until and / or along an edge between the upper surface and the side surface (on the distal end face) such that this electrically conductive layer is exposed in the closed position of the first jaw and the second jaw. Thus, the second radiofrequency path may extend over the side surface on the distal end face.

[0153] In an alternative optional embodiment, a rigid and unitary isolator forms the first isolating portion and the second isolating portion. Optionally, the isolator includes an upper surface forming sections of the first surface and a lower surface facing away from the first surface. Further optionally, electrically conductive layers are arranged on the upper surface forming the first electrode, the second electrode, and / or the third electrode. In an example, the electrically conductive layers are arranged on the lower surface forming the third electrode in electrical contact with the solid block. Optionally, the distal electrode comprises an electrically conductive element electrically isolated from the solid block by a distal isolating portion of the second isolating portion. The electrosurgical instrument further includes an RF transmission line extending in the first jaw and electrically connected between the distal electrode and the transmission line.

[0154] The above-described optional embodiments, features, and / or characteristics of the rigid and unitary isolator, the first electrode, the second electrode, and / or the third electrode equally apply for this embodiment, except for the following differences.

[0155] The first electrode and / or the second electrode terminate well before the distal end of the isolator. In other words, a gap is formed between the distal end of the isolator and the distal ends of the first electrode and / or the second electrode. For example, the first electrode of this embodiment has the same arrangement as the first electrode described above. However, the second electrode does not extend beyond the first electrode in the longitudinal direction and / or terminates at the same location in the longitudinal direction as the first electrode. The gap between the distal ends of the first electrode and / or the second electrode and the distal end of the isolator ensures that the first radiofrequency path is contained between the first jaw and the second jaw in the closed position.

[0156] The electrically conductive layer forming the third electrode on the lower surface may be spaced away from the distal end of the isolator and / or the distal end face of the first jaw. The distal electrode is arranged directly or indirectly on the lower surface. The distal electrode of this example may include an electrically conductive component that is separate from the electrically conductive layer covering the isolator. The distal electrode may protrude from the distal end face of the first jaw and / or may not be arranged on the upper surface of the isolator.

[0157] As the distal electrode is arranged on the lower surface, the distal electrode needs to be electrically isolated from the third electrode, for example the solid element of the third electrode. To this end, the distal isolating portion is provided which is exposed on the distal end face. For example, the distal electrode is electrically isolated from the first electrode, the second electrode, and / or the third electrode by the isolator and the distal isolating portion.

[0158] The distal isolating portion may a portion of the second isolating portion that is separated from the isolator (as another portion of the second isolating portion). The distal isolating portion may be made from a material different to the material of the isolator. For example, the distal isolating portion is made from silicone.

[0159] The second radiofrequency path may extend over the distal isolating portion exposed on the distal end face to the third electrode, for example the section of the solid element that is exposed on the distal end face. In other words, the distal isolating portion may fill a gap between the distal electrode and the third electrode at the distal end face, similar to the configuration described above.

[0160] As the distal electrode is electrically isolated from the other electrodes and arranged at the distal end of the first jaw, a separate RF transmission line is provided within or on the first jaw for electrically connecting the distal electrode to the transmission line. This RF transmission line may be a wire or cable that extends through the solid element of the third electrode.

[0161] In an optional embodiment, the third electrode includes a solid element forming the longitudinal section and the distal section. Optionally, the solid element of the third electrode includes an inner surface facing the second jaw in the closed position and an outer surface exposed in the closed position. Further optionally, the second isolating portion covers the entire inner surface. In an example, the electrosurgical instrument further includes an RF transmission line extending in the first jaw and electrically connected between the distal electrode and the transmission line.

[0162] The above-described optional embodiments, features, and / or characteristics of the solid element, the first electrode, the second electrode, the third electrode, fourth electrode, the second isolating portion, and / or the second jaw equally apply for this embodiment, except for the following differences.

[0163] In an example, the second electrode may be arranged on the second surface. Thus, in this example, the first electrode and the second electrode are not arranged exposed on the first surface. The first electrode is arranged exposed on the first surface and / or the second electrode is arranged exposed on the second surface. The second electrode may include one or more longitudinal sections that extend along and / or parallel to the first electrode in the closed position. For example, the longitudinal section(s) of the second electrode of this embodiment may be similar to equal to the longitudinal section(s) of the third electrode described above. The longitudinal sections of the second electrode extend on either side of the first electrode in the closed position. The first isolating portion may form a layer on the inner surface of the fourth electrode, for example the inner surface of the solid element of the fourth electrode of the second jaw. For example, the longitudinal section(s) of the second electrode may be arranged exposed on the first isolating portion. In the closed position, there is a gap between the first electrode and the longitudinal section(s) of the second electrode. With this embodiment, the first radiofrequency path extends between the first surface and the second surface. The third radiofrequency path may extend from the first or second electrodes over the first surface to the longitudinal sections of the third electrode that are arranged on the outer surface of the first jaw.

[0164] In another example, the second electrode may be arranged on the first surface. Thus, in this example, the first electrode and the second electrode are arranged exposed on the first surface. The second electrode may include one or more longitudinal sections that extend along and / or parallel to the first electrode on the first surface. For example, the longitudinal section(s) of the second electrode of this embodiment may be similar to equal to the longitudinal section(s) of the third electrode described above. The longitudinal sections of the second electrode extend on either side of the first electrode on the first surface.

[0165] For example, the longitudinal section(s) of the second electrode may be arranged exposed on the electrically isolating layer forming the second isolating portion. There is a gap between the first electrode and the longitudinal section(s) of the second electrode. The first isolating portion may be provided by the section of the isolating layer on the inner surface that is arranged between the first electrode and the longitudinal section(s) of the second electrode.

[0166] With this example, the first radiofrequency path extends along the first surface. The third radiofrequency path may extend from the second electrode over the first surface to the longitudinal sections of the third electrode that are arranged on the outer surface of the first jaw.

[0167] In line with the general concept described above, the maximal length of the first radiofrequency path (e.g. the effective distance between the first electrode and the second electrode) is smaller than the minimal length of the second radiofrequency path (e.g. effective distance between the distal end of the first electrode and the distal electrode). For example, edges of the longitudinal section(s) of the second electrode are closer to the exposed sections of the first electrode compared to the distal end of the exposed section of the first electrode and the distal electrode. With this configuration, the radiofrequency energy can be contained between the first jaw and the second jaw in the closed position.

[0168] The RF transmission line may extend in or on the first jaw and / or may include a cable or wire. The distal electrode is arranged at the distal end of the first jaw. For example, the distal electrode is electrically isolated from the third electrode by the second isolating portion. The distal electrode may form a block, for example as described above. In this embodiment, the distal electrode is not electrically coupled to the second electrode. Rather, the separate RF transmission line is provided for electrically connecting the distal electrode to the transmission line.

[0169] The distal electrode may not be electrically powered (e.g. subjected to radiofrequency energy) when tissue cutting along the first radiofrequency path is effected. Thus, the distal electrode may not be electrically coupled to the second electrode. The distal electrode may be powered when providing tissue cutting using the second radiofrequency path and / or the third frequency path.

[0170] In an optional embodiment, the RF transmission line extends within the second isolating portion. Optionally, the RF transmission line supports the distal electrode.

[0171] The RF transmission line may extend completely immersed in the second isolating portion. The RF transmission line may be a rigid component and / or may correspond in this configuration and / or shape to the second electrode described above. For example, the structure of this embodiment including the first electrode, RF transmission line, and the distal electrode may correspond to the structure of the previous embodiments including the first electrode, the second electrode, and the distal electrode whereby the structure is rotated by 90° around the longitudinal direction. For example, the RF transmission line extends parallel to the first electrode and beyond the first electrode towards the distal end. The distal electrode may be integrally formed with the RF transmission line. In this way, the RF transmission line provides mechanical support for the distal electrode on the distal end face.

[0172] In an optional embodiment, the electrosurgical instrument further comprises a switch unit that is switchable between a first connection state and a second connection state. Optionally, the switch unit is in the first connection state when the first jaw and the second jaw are in the closed position.

[0173] The switch unit may include a switch for switching between the first connection state and the second connection state and / or a position sensor configured to detect the position of the first jaw and / or the second jaw, for example relative to each other. The position sensor may be configured to (only) detect whether the first jaw and the second jaw are in the open position and / or in the closed position. The position sensor may include a mechanical, electrical and / or electronic means for detecting the orientation of the first jaw and the second jaw, a distance between the first jaw and the second jaw, and / or whether the first jaw and the second jaw contact each other. For example, the position sensor may include a capacitor for sensing a distance between the first jaw and the second jaw. The detection result of the position sensor is used by the switch for controlling to the switch to be in the first connection state or the second connection state.

[0174] The switch unit, for example the switch and / or the position sensor, may be arranged on the first jaw, the second jaw, the instrument shaft, and / or the joint. The switch unit may only include a mechanical switch which is mechanically connected to the first jaw and the second jaw. A movement of the first jaw relative to the second jaw actuates the mechanical switch. For example, when moving the first jaw and / or the second jaw into the closed position, the mechanical switch is put into the first connection state. On the other hand, moving the first jaw and / or the second jaw into the open position, the mechanical switch is put into the second connection state.

[0175] The closed position may refer to an orientation of the first jaw and the second jaw such that the first surface and the second surface are in contact with each other, extend parallel to each other and have a distance relative to each other which is below a certain threshold, and / or an orientation of the first surface relative to the second surface which is below a threshold angle, for example 3°, 5°, or 10°. The above exemplary definitions of the closed position may include variations from an absolute closed position in which the first surface entirely contacts the second surface. This is done in view of the fact that tissue might be present between the first jaw and the second jaw such that the first jaw and the second jaw are not completely in the closed position due to the presence of the tissue between the first jaw and the second jaw.

[0176] If the first jaw the second jaw are not in the closed position, they may be assumed to be in the open position. In another example, the open position may be defined as the first surface and the second surface being maximally spaced apart, extending parallel to each other and having a distance relative to each other above a certain threshold, and / or an orientation of the first surface relative to the second surface is above a threshold angle, for example 30°, 35°, or 40°. In this case, there might be an intermediate range of the first jaw and the second jaw in which the electrosurgical instrument is neither in the open position nor the closed position.

[0177] The presence of the switching unit allows to automatically select between the various radiofrequency paths by assigning one or more radiofrequency paths to the first connection state and the second connection state. Thus, the electrosurgical instrument allows the control of the connection state by opening and closing the first jaw and the second jaw.

[0178] In an alternative embodiment, a radiofrequency path may be selected by supplying the radiofrequency energy to the desired electrode(s). This may be done by a switch or switching network arranged on the generator and / or a handpiece of the electrosurgical instrument. In this case, this needs to be manually done. It is also possible that the electrosurgical instrument includes the position sensor as described above which is in data communication with the switching network. With this example, the switching between the first connection state and the second connection state may be automatically executed at the generator and / or the handpiece. In an optional embodiment, in the first connection state, the switch (unit) connects a first pole of the radiofrequency energy to the first electrode and a second pole of the radiofrequency energy to the second electrode. Optionally, in the second connection state, the switch (unit) connects a first pole of the radiofrequency energy to the first electrode, the second electrode, and the distal electrode and a second pole of the radiofrequency energy to the third electrode.

[0179] In the first connection state, the radiofrequency electromagnetic energy is applied along the first radiofrequency path. In a second connection state, the radiofrequency electromagnetic energy is applied along the first radiofrequency path and / or the second radiofrequency path.

[0180] The presence of the switching unit allows to automatically apply the radiofrequency energy along the first radiofrequency path if the first jaw and the second jaw are in the closed position. As described above, the first radiofrequency path is used to cut tissue by also applying mechanical pressure which is done by bringing the electrosurgical instrument closed position. Thus, a user of the electrosurgical instrument does not need to manually switch from the second connection state to the first connection state upon bringing the electrosurgical instrument from the open position to the closed position.

[0181] Further, the presence of the switching unit allows to automatically apply the radiofrequency energy along the second radiofrequency path and / or the third radiofrequency path if the first jaw and the second jaw are in the open position. As described above, the second radiofrequency path and / or the third radiofrequency path are used to puncture tissue and / or provide gliding cut, e.g. by not clamping the tissue between the jaws. In other words, the electrosurgical instrument is in the open position when puncturing tissue and / or cutting tissue as a gliding cut. Thus, a user of the electrosurgical instrument does not need to manually switch from the first connection state to the second connection state upon bringing the electrosurgical instrument from the closed position to the open position.

[0182] The electrosurgical instrument according to the second aspect may not be a jawed instrument, for example an electrosurgical instrument for which the electrodes are movable relative to the instrument shaft. Rather, it is possible that the isolating portion is non-movably fixed or attached to the instrument shaft. As the electrodes of the second aspects are layers on the isolating portion, the electrodes are also nonmovable relative to the instrument shaft.

[0183] The structure including the first to third electrodes and the isolating portion may form an antenna structure for emitting radiofrequency electromagnetic energy that is optionally non-movably fixed to the instrument shaft.

[0184] The isolating portion of the second aspect may include the same characteristics, optional features, and / or embodiments as the second isolating portion (of the first aspect) in the form of the rigid and unitary isolator described above. Further, the conductive layers of the electrosurgical instrument according to the second aspect may have to same characteristics, optional features, and / or embodiments as the conductive layers described in connection with the first aspect.

[0185] The electrosurgical instrument of the second aspect relates to the location on the isolating portion where the radiofrequency energy is applied to the tissue. Thus, the electrosurgical instrument of the second aspect may include various radiofrequency paths. The configuration and / or arrangement of the first to third electrodes on the isolating portion provides that only a single radiofrequency path is in operation because all other radiofrequency paths are electrically unfavourable.

[0186] The selection of the radiofrequency path is provided by the edge sections which correspond those regions of the first to third electrodes which are closest to another electrode compared to other regions of the same electrode to the corresponding other electrode. This may mean that, if radiofrequency energy is applied to the first electrode and the second electrode, the electrical current only flows between the edge section of the first electrode and the edge section of the second electrode and not between other regions of the first electrode and other regions of the second electrode. In other words, the radiofrequency path is confined to the edge sections of the first electrode and second electrode. This configuration may also apply to the edge sections of the pair of second and third electrode and / or the pair of first electrode and third electrode.

[0187] Similar to the configuration of the first aspect, the confinement of the electrical current to the edge sections is implemented by shaping the conductive layers of the electrodes such that the maximal length of the radiofrequency path or the maximum effective distance between the edge section of the first electrode and the edge section of the second electrode is smaller than the minimal length of the radiofrequency path or the minimal effective distance between any other region of the first electrode and any other region of the second electrode. The above considerations equally apply to the pair including a first electrode and the third electrode and / or the pair including a second electrode and third electrode.

[0188] The edge section may extend along the edge of the isolating portion, i.e. the edge between the upper surface and the side surface. The conductive layers of the first of third electrodes may not be arranged on the side surface. In other words, the side surfaces may be free from electrically conductive layers.

[0189] The edge sections may correspond those regions of the first to third electrodes which are involved in radiofrequency cutting. The other regions of the first to third electrodes may be provided for electrically connecting the edge sections to the transmission line. A gap between adjacent edge sections may have a constant width. The edge sections of the first to third electrodes may be identified as those regions of the first to third electrodes that have the shortest / shorter distance to an adjacent electrode (e.g. the edge section of the adjacent electrode) compared to any other region of the first to third electrodes.

[0190] The edge section may have breadth from the edge less than 5 mm, 4 mm, 3 mm, 2 mm, or 1 mm. Alternatively, the edge section may have breadth, which is less than 30 %, 25 %, 20 %, 15, or 10 % of the width of the isolating portion (measured perpendicular to the longitudinal direction).

[0191] In this way it is possible to confine the electric current flowing upon applying radiofrequency energy to the edge sections. For example, the radiofrequency cut can be effected at two different positions along the edge of the isolating portion. This may allow to provide radiofrequency tissue cutting on the left / first side or the right / second side of the isolating portion. This may be helpful in cases where tissue is in contact with all or many regions of the isolating portion such that, if no confinement of the radiofrequency cutting present, the tissue would be cut in places where it is not intended. Such situations may arise where there is little space for the electrosurgical instrument, for example when the electrosurgical instrument pushes away tissue. In the circumstances, confined radiofrequency cutting is possible.

[0192] In an optional embodiment, the edge section of the first electrode covers a distal end region of the upper surface. The first electrode further includes a central section extending between the edge section of the second electrode and the edge section of the third electrode.

[0193] The central section of the first electrode may be provided for electrically connecting the edge section of the first electrode with the transmission line. The second electrode and / or the third electrode may only include the edge sections which may run parallel to the central section of the first electrode. The first electrode may extend from the distal end of the isolating portion to the proximal end of the isolating portion. The transmission line may be connected to the central section at the proximal end of the isolating portion.

[0194] The second electrode and / or the electrode may extend from the proximal end of the isolating portion to a point spaced apart from the distal end of the isolating portion. This is because the distal end of the first isolating portion is covered by the edge section of the first electrode.

[0195] The central section may have a small width, for example an extension perpendicular to the longitudinal direction. As the distance between the central section of the first electrode to any other region of the second and / or third electrode needs to be larger than the distance between the respective edge sections, the second electrode and / or the third electrode may only extend along the edge of the isolating portion. In other words, the second electrode and / or the third electrode may only include edge sections and / or are formed by strips of conductive layer along the edge between the upper surface and the side surface. In this case, radiofrequency cutting can be effected between the distal ends of the second electrode and / or the third electrode and proximal ends of the edge section of the first electrode.

[0196] In an optional embodiment, the electrosurgical instrument further comprises a fourth electrode covering at least an edge portion of the lower surface.

[0197] The edge portion may be that region of the lower surface that is adjacent to or in contact with the edge between the lower surface and the side surface. For example, the fourth electrode may extend along the entire edge between the lower surface and the side surface.

[0198] The fourth electrode may cover the entire back surface of the isolating portion. Radiofrequency cutting can be effected between the fourth electrode and the sections of the first electrode, the second electrode, and / or the third electrode. Thus, this type of radiofrequency cutting may be used for radiofrequency cutting along the entire side surface of the isolating portion. In this example, the first to third electrodes may be coupled to the first pole of the radiofrequency energy and the fourth electrode is connected to the second pole of the radiofrequency energy.

[0199] In an optional embodiment, the generator unit is configured to supply the radiofrequency energy to (i) the first electrode and the second electrode for cutting tissue between the edge sections of the first and second electrodes, (ii) the first electrode and the third electrode for cutting tissue between the edge sections of the first and third electrodes, and / or (iii) the first electrode, the second electrode, and / or the third electrode as a first pole and to the fourth electrode as a second pole for effecting tissue cutting between the upper surface and the lower surface.

[0200] The generator unit may be configured to generate electromagnetic energy of a fixed single frequency or of a plurality of fixed single frequencies. Alternatively or additionally, the generator unit may be tuneable to generate electromagnetic energy of various frequencies, for example in a continuous range of frequencies between a minimum frequency and a maximum frequency. The generator unit may be connected to a power supply which provides the energy for generating the radiofrequency electromagnetic energy and / or microwave electromagnetic energy.

[0201] The generator unit is electrically and / or electronically (directly or indirectly) connected to the transmission line. Optionally, the generator unit generates the radiofrequency energy and / or microwave energy which is conveyed by the transmission line to the first to fourth electrodes where the radiofrequency energy and / or microwave energy is radiated into the treatment zone.

[0202] For example, the generator unit includes a generator that is configured to simultaneously generate electromagnetic energy of two different (fixed) frequencies.

[0203] Alternatively, the generator unit includes a first generator for generating electromagnetic energy of the first frequency and a second generator for generating electromagnetic energy of the second frequency. The output of the first generator and output of the second generator can be combined using a multiplexer and / or routed to different electrodes using the switching unit.

[0204] The multiplexer may be a diplexer and can combine the input from various sources into one output. For example, a multiplexer (or diplexer) is used to combine the output of first and second generators to a single output which is connected or coupled to the transmission line.

[0205] In an optional embodiment, the transmission line includes a first (coaxial) cable is connected to the generator unit to receive the first frequency and a second (coaxial) cable is connected to the generated unit to receive the first frequency and / or the second frequency. Optionally, the first (coaxial) cable is connected to the first electrode and the second electrode and the second (coaxial) cable is connected to the first and second electrodes (as first pole) and the third electrode and distal electrode (as second pole).

[0206] Here again, the generator unit may include a first generator for generating electromagnetic energy of the first frequency and a second generator for generating electromagnetic energy of the second frequency. The first (coaxial) cable is connected to the first generator and the second (coaxial) cable is connected to the second generator.

[0207] In an optional embodiment, the generator unit is configured to simultaneously or alternatingly generate radiofrequency electromagnetic energy of the first frequency and radiofrequency electromagnetic energy of a third frequency.

[0208] BRIEF DESCRIPTION OF THE DRAWINGS

[0209] Embodiments of the invention are described in detail below with reference to the accompanying drawings, in which:

[0210] Fig. 1 shows a schematic view of an embodiment of an electrosurgical apparatus including an electrosurgical instrument;

[0211] Fig. 2a shows a perspective view of a first jaw of an embodiment of the electrosurgical instrument shown in Fig. 1;

[0212] Fig. 2b shows a top view on a distal end section of the first jaw of the electrosurgical instrument shown in Fig. 2a;

[0213] Fig. 2c shows a top view on a distal end section of a second jaw of the electrosurgical instrument shown in Fig. 2a in a closed position;

[0214] Fig. 3a shows a perspective view on a distal end section of the first jaw of an embodiment of the electrosurgical instrument shown in Fig. 1;

[0215] Fig. 3b shows another perspective view on a distal end section of the first jaw of the electrosurgical instrument shown in Fig. 3a with first and second sealing portions removed; Fig. 4a shows a perspective view of an embodiment of the electrosurgical instrument (in the closed position) shown in Fig. 1;

[0216] Fig. 4b shows a perspective view on a distal end section of the first jaw of the electrosurgical instrument shown in Fig. 4a;

[0217] Fig. 4c shows a cross-sectional view of the electrosurgical instrument shown in Fig. 4a in the closed position;

[0218] Fig. 5a shows a perspective view of an end section of a first jaw of an embodiment of the electrosurgical instrument shown in Fig. 1;

[0219] Fig. 5b shows another perspective view of the end section of the first jaw of the electrosurgical instrument shown in Fig. 5a;

[0220] Fig. 5c shows a cross-sectional view of the electrosurgical instrument shown in Figs. 5a and 5b in the closed position;

[0221] Fig. 6a shows a perspective view of an end section of a first jaw of an embodiment of the electrosurgical instrument shown in Fig. 1;

[0222] Fig. 6b shows a top view (left drawing) and a bottom view (right drawing) on a first isolating portion of the electrosurgical instrument shown in Fig. 6a;

[0223] Fig. 6c shows a side view on a distal end section of the first jaw of the electrosurgical instrument shown in Fig. 6a;

[0224] Fig. 7a shows a perspective view of an end section of a first jaw of an embodiment of the electrosurgical instrument shown in Fig. 1;

[0225] Fig. 7b shows a top view (left drawing) and a bottom view (right drawing) on a first isolating portion of the electrosurgical instrument shown in Fig. 7a;

[0226] Fig. 7c shows a side view on a distal end section of the first jaw of the electrosurgical instrument shown in Fig. 7a;

[0227] Fig. 8a shows a perspective view of an end section of a first jaw of an embodiment of the electrosurgical instrument shown in Fig. 1;

[0228] Fig. 8b shows a cross-sectional view of the electrosurgical instrument shown in Fig. 8a in the closed position;

[0229] Fig. 9a shows a perspective view of an embodiment of the electrosurgical instrument (in the closed position) shown in Fig. 1;

[0230] Fig. 9b shows a perspective view of an end section of the electrosurgical instrument shown in Fig. 9a;

[0231] Fig. 9c shows a cross-sectional view of the electrosurgical instrument shown in Fig. 9a in the closed position;

[0232] Fig. 10a shows a perspective view of an embodiment of an electrosurgical instrument of the electrosurgical apparatus shown in Fig. 1; and

[0233] Fig. 10b shows a side view of the electrosurgical instrument shown in Fig.

[0234] 10a. DETAILED DESCRIPTION; FURTHER OPTIONS AND PREFERENCES

[0235] The present invention relates to an electrosurgical instrument and apparatus capable of delivering microwave and / or bipolar radiofrequency electromagnetic energy to seal tissue (e.g. blood vessels) and of cutting the tissue. The electrosurgical instrument and apparatus may be used in open surgery but may find particular use in procedures where there is restricted access to the treatment site. For example, the electrosurgical instrument of the invention may be adapted to fit within the instrument channel of a laporoscopic trocar or a surgical scoping device e.g. laparoscope, endoscope, or the like. Fig. 1 shows a schematic view of an electrosurgical apparatus 10 in which the electrosurgical instrument of the invention may be used.

[0236] Fig. 1 is a schematic diagram of a complete electrosurgical apparatus 10 that is an embodiment of the invention. The electrosurgical apparatus 10 is arranged to treat biological tissue using radiofrequency (RF) and / or microwave electromagnetic (EM) energy delivered from an electrosurgical instrument 12. The EM energy emitted by the electrosurgical instrument 12 into a treatment zone can be used to coagulate, cut, and / or ablate tissue in the treatment zone. Optionally, the electrosurgical apparatus 10 is arranged to treat biological tissue using radiofrequency (RF) electromagnetic (EM) energy only. Further, the electromagnetic energy emitted by the electrosurgical instrument 12 into a treatment zone can be used to only cut tissue in the treatment zone.

[0237] The electrosurgical apparatus 10 further comprises a generator unit 14 which can controllably supply radiofrequency and / or microwave electromagnetic energy to the electrosurgical instrument 12. The generator unit 14 may include a first generator 16 and / or a second generator 17. Suitable generators for this purpose are described in WO 2012 / 076844, which is incorporated herein by reference. The generator unit 14 may be arranged to monitor reflected signals received back from the electrosurgical instrument 12 in order to determine an appropriate power level for delivery. For example, the generator unit 14 may be arranged to calculate an impedance seen at the electrosurgical instrument 12 in order to determine an optimal delivery power level.

[0238] The electrosurgical apparatus 10 further comprises a surgical scoping device 20, such as a bronchoscope, endoscope, gastroscope, laparoscope or the like. The scoping device 20 may include a handpiece 20a and a flexible or rigid shaft 22. The handpiece 20a may include means for guiding the flexible shaft 22 through a cavity of a body. For example, the handpiece 20a can include means for moving a distal end of the flexible shaft 22 to change direction of the distal end of the flexible shaft 22. This helps manoeuvring the flexible shaft 22 through the cavity of the body. The flexible shaft 22 may include a working channel through which elongated structures can be moved and, thus, positioned at the treatment zone within the cavity of the body.

[0239] The first generator 16 and / or the second generator 17 are each configured to generate electromagnetic energy of a fixed frequency. However, the generator unit 14 is not limited thereto; the first generator 16 and / or the second generator 17 can be configured to generate AC electromagnetic energy in a continuous range between a minimum frequency and a maximum frequency. The frequency of the electromagnetic energy to be generated by the first generator 16 and / or the second generator 17 may be selected using an interface (not shown in the figures).

[0240] The generator unit 14 can include a switch 24 which is electrically connected or coupled to the first generator 16 and to the second generator 17. The switch 24 selectively connects the outputs of the first generator 16 and the second generator 17 to one or more electrodes as described below.

[0241] The generator unit 14 is thus capable of generating and controlling power to be delivered to the electrosurgical instrument 12, e.g. via a transmission line 28, which extends from the generator unit 14 through the surgical scoping device 20 and instrument channel to the distal tip of the instrument channel. The generator unit 14 may have a user interface for selecting and / or controlling the power delivered to the electrosurgical instrument 12, e.g. controlling the first and / or second generators 16, 17 and / or the switch 24. The generator unit 14 may have a display for showing the selected energy delivery mode and / or connection state. In some examples, the generator unit 14 may allow for an energy delivery mode to be selected based on the size of the vessel to be cut.

[0242] The electrosurgical instrument 12 can include the transmission line 28, an instrument shaft 30, a joint, a first jaw 34, and / or a second jaw 36 which will be discussed in further detail in connection with Figs. 2a to 2c. The transmission line 28 may include a one or more coaxial cables that connect the generator unit 14 to the first jaw 34 and / or second jaw 34 for conveying the radiofrequency and / or microwave energy.

[0243] Figs. 2a to 2c show schematic views of an embodiment of the electrosurgical instrument 12. The first jaw 34 and the second jaw 36 are rotatably or pivotally connected or coupled to the instrument shaft 30 (not shown in Figs. 2a to 2c) which is dimensioned to fit within the instrument channel of the surgical scoping device 20. The instrument shaft 30 comprises a tubular sheath that covers the transmission line 28 for carrying microwave and / or radiofrequency energy to the jaws 34, 36 together with various control wires or (actuation) rods that are arranged to control and / or physically manipulate the first and second jaws 34, 36, as discussed below.

[0244] The first jaw 34 and the second jaw 36 are operably coupled to a joint (not shown in the figures) that is mounted on a distal end of the instrument shaft 30. Both the first and second jaws 34, 36 may be arranged to pivot relative to the joint. The joint may be arranged to ensure that the jaws remain laterally aligned as they are moved together.

[0245] In an alternative embodiment, the pair of jaws 34, 36 comprises a static jaw that is fixed relative to the instrument shaft 30 or the joint. The other jaw is pivotable or rotatable.

[0246] The joint may include a pivot axle which defines a pivot axis. The first jaw 34 and the second jaw 36 can pivot around the pivot axis or pivot axle. For example, the pivot axle is fixed to the joint and the first jaw 34 and the second jaw 36 can rotate around the pivot axle.

[0247] In use, the first jaw 34 and the second jaw 36 are intended to grip biological tissue (in particular a blood vessel) therebetween. The first jaw 34 and the second jaw 36 are arranged to apply pressure to the biological tissue between the opposed surfaces of the jaws 34, 36 and deliver energy (preferably microwave and / or radiofrequency electromagnetic energy) into the tissue from the transmission line 28.

[0248] The first jaw 34 includes a first surface 50 which opposes a second surface 52 of the second jaw 36. The first surface 50 and / or the second surface 52 may form an outer surface of the first jaw 34 and the second jaw 36 respectively, which can be brought into contact with each other when the jaws 34, 36 are in the closed position. For example, the first surface 50 and the second surface 52 (not shown in Figs. 2a to 2c) may be considered pressure pads or pressure areas with which pressure can be applied to the tissue grasped between the first jaw 34 and the second jaw 36.

[0249] In the embodiment of Figs. 2a to 2c, the first jaw 34 includes a first electrode 54, a second electrode 56, a third electrode 58, a distal electrode 60, a fourth electrode 62, a first isolating portion 64, a second isolating portion 66, a third isolating portion 68, a fourth isolating portion 70, and / or a fifth isolating portion 72. The first electrode 54, the second electrode 56, and / or the third electrode 58 are made from an electrically conductive material, such as metal or a metal alloy.

[0250] The first isolating portion 64 electrically isolates the first electrode 54 from the second electrode 56. The first isolating portion 64 may be made from an electrically non-conductive material such as a ceramic material (e.g. including Zirconia), PEEK, silicone, and / or other plastic materials. The first isolating portion 64 may be sandwiched between the first electrode 54 and the second electrode 56. The first isolating portion 64 may be flush with the exposed edge or section of the first electrode 54 and the second electrode 56.

[0251] The first electrode 54 and / or the second electrode 56 may extend in the longitudinal of the first jaw 34 and / or extend parallel to each other forming a gap therebetween having a distance b (see Fig. 2b). The first electrode 54 and / or the second electrode 56 may have an elongate shape, for example as a bar or plank. The first electrode 54 and / or the second electrode 56 are sufficiently rigid such that they are not deformed when tissue is clamped between the first surface 50 and the second surface 52.

[0252] The first electrode 54 and / or the second electrode 56 may extend from a proximal end of the first jaw 34 towards the distal end of the first jaw 34. At the proximal end of the first jaw 34, the first electrode 54 and / or the second electrode 56 can be connected to the transmission line 28. The second electrode 56 may extend beyond the first electrode 54 in the longitudinal direction towards the distal end of the first jaw 34.

[0253] The distal electrode 60 may be integrally formed with the second electrode 56. The distal electrode 60 may protrude from a distal end face 76 of the first jaw 34. Thus, in the closed position of the first jaw 34 and the second jaw 36, the distal electrode 60 is exposed at the distal end face 76 for contacting tissue.

[0254] The distal electrode 60 may form a solid block arranged at the distal end face 76. The distal electrode 60 may be solely connected to the second electrode 56 such that distal electrode 60 is mechanically supported by the second electrode 56. A proximal end of the distal electrode 60 may have a minimum distance a (see Fig. 2b) to a distal end of the first electrode 54. The minimum distance a is larger than the distance b which forms a maximal distance between the first electrode 54 and the second electrode 56.

[0255] The distal electrode 60 may have a width in a lateral direction (perpendicular to the longitudinal direction) that corresponds to the width of the first electrode 54 and the second electrode 56. For example, as apparent from Fig. 2c, a side surface of the first electrode 54 is in a line with a side surface of the distal electrode 60 and / or a side surface of the second electrode 56 is in a line with a side surface of the distal electrode 60.

[0256] The first electrode 54 and / or the second electrode 56 are completely contained within the perimeter of the first surface 50. In words, the first electrode 54 and / or the second electrode 56 are not exposed for contacting tissue in the closed position of the first jaw 34 and the second jaw 36. For example, the distance of the first electrode 54 and the second electrode to the distal end face 76 is equal to the distance a.

[0257] The first electrode 54 and / or the second electrode 56 are supported by and electrically isolated from the third electrode 58 by the second isolating portion 66. In the embodiment of Figs. 2a to 2c, the first isolating portion 64 is integrally formed with the second isolating portion 66. The first isolating portion 64 and / or the second isolating portion 66 can be made from silicone. Due to the elasticity of silicone, the first electrode 54 and / or the second electrode 56 can “float” on the third electrode 58. In other words, the first electrode 54 and / or the second electrode 56 can move relative to the third electrode 58 when pressure is applied to the first electrode 54 and / or the second electrode 56, for example if tissue is clamped between the first jaw 34 and the second jaw 36.

[0258] The third electrode 58 may be a solid element having an elongate recess extending in the longitudinal direction. The structure including the first electrode 54, the second electrode 56, the first isolating portion 64, and / or the second isolating portion 66 can be fixed to and / or arranged within the elongate recess.

[0259] The third electrode 58 may include (two) longitudinal sections 58a and the distal section 58b. The longitudinal sections 58a extend parallel to and on either side of the first electrode 54 and the second electrode 56. In the example of Figs. 2a to 2c, the longitudinal sections 58a are surface sections arranged and / or exposed on the first surface 50 for contacting tissue.

[0260] The distal section 58b forms an exposed area of the third electrode 58 on the distal end face 76. The second isolating portion 66 is also exposed at the distal end face 76 such that the second isolating portion 66 electrically isolates the distal electrode 60 from the distal section 58b at the distal end face 76.

[0261] The third electrode 58 may form the outer surface of the first jaw 34 and / or may provide the connection to the joint. Thus, the third electrode 58 may have a function of providing the stability of the first jaw 34.

[0262] The third isolating portion 68 may cover the (entire) outer surface of the first jaw 34 and / or the third electrode 58. Further, the third isolating portion 68 may cover a section of the first jaw 36 and / or the distal section 58b of the third electrode 58. For example, the second isolating portion 66 and the third isolating portion 68 are arranged at the distal end face 76 such that the exposed distal section 58b of the third electrode 58 forms a half-circle around the distal electrode 60.

[0263] The second jaw 36 may include the fourth electrode 62 which may be provided by a solid element. The fourth electrode 62 can be mirror symmetric to the third electrode 58 in the closed position except for the elongate recess. The fourth isolating portion 70 may cover an inner surface of the fourth electrode 62 that faces the first surface 50 in a closed position. The fourth isolating portion 70 may cover the entire inner surface of the fourth electrode 62 and / or may provide the second surface 52.

[0264] The fifth isolating portion 72 may cover an outer surface of the second jaw 36 and / or the fourth electrode 62. The fourth isolating portion 70 and the fifth isolating portion 72 may be arranged at the distal end face of the second jaw 36 such that the fourth electrode 62 is exposed in a half-circle around the distal electrode 60 in the closed position. Thus, the distal section 58b and the exposed section of the fourth electrode 62 may form a circle around the distal electrode in the closed position. The fourth isolating portion 70 and / or the fifth isolating portion 72 can be made from silicone. The electrosurgical instrument 12 may further include a switching unit 74 which is schematically shown in Fig. 2a. The switching unit 74 may be configured to detect whether the electrosurgical instrument 12 is in the closed position or the open position. This may be done by capacitively sensing a distance between the first jaw 34 and the second jaw 36 and / or by mechanically detecting the orientation of the first jaw 34 relative to the second jaw 36.

[0265] When the electrosurgical instrument 12 is in the closed position, a switch of the switching unit 72 is a first connection state in which the radiofrequency energy transmitted by the transmission line 28 is supplied to the first electrode 54 and the second electrode 56. When the electrosurgical instrument 12 is in the open position, the switch of the switching unit 72 is in a second connection state in which the first pole of the radiofrequency energy transmitted by the transmission line 28 is supplied to the first electrode 54 and the second electrode 56 and a second pole of the radiofrequency energy transmitted by the transmission line 28 is supplied to the third electrode 58.

[0266] Thus, in the second connection state, an electric current induced by the radiofrequency energy may flow from the assembly of the first electrode 54 and the second electrode 56 to the exposed longitudinal sections 58a on either side. Thus, the electric current flows from the metallic parts labelled (1) + (2) to (4). This third radiofrequency path is highlighted by the arrows in Fig. 2a. Further, in the first connection state, an electric current induced by the radiofrequency energy may flow from the distal electrode 62 to the distal section 58b and / or to the exposed section of the fourth electrode 62. This second radiofrequency path is highlighted by the arrows the arrows in Fig. 2a. In summary, in the second connection state, the electric current flows from the metallic parts labelled (1) to (3) or (4).

[0267] In the first connection state, an electric current induced by the radiofrequency energy may flow from the first electrode 54 to the second electrode 56. Thus, the electric current flows between the metallic parts labelled (1) and (2). This first radiofrequency path is highlighted by the arrow in Fig. 2b. However, due to the larger distance a compared to the distance b, no current is flowing from the distal electrode 62 to the first electrode 54 (or vice versa). Thus, even though the distal electrode 60 is subjected to radiofrequency electromagnetic energy in the first connection state, the electric current induced by the radiofrequency energy is confined between the first jaw 34 and the second jaw 36 in the closed position.

[0268] The first connection state may be used if the first jaw 34 and the second jaw 36 are in the closed position. In this case, pressure is applied to the tissue clamped between the first jaw 34 and the second jaw 36. The increased pressure helps to cut tissue even though the tissue might be dry or dried out which the increases the efficiency of the radiofrequency cut. The second connection state may be used if the first jaw 34 and the second jaw 36 are in the open position. The radiofrequency cutting in the second connection state may be used to provide a gliding cut in such a way that the radiofrequency cut is similar used to a mechanical blade. The tissue to be cut is pressed against the first electrode 54 and the second electrode 56, more generally against the first surface 50, and cut using the radiofrequency energy.

[0269] The second connection state may also be used if the first jaw 34 and the second jaw 36 are in the closed position. The radiofrequency electromagnetic energy may be used to puncture tissue. There, the second radiofrequency path for the distal electrode 62 to the distal section 58b and / or the exposed section of the fourth electrode 62 may provide a cut at the distal end of the electrosurgical instrument 12 for puncturing tissue.

[0270] The embodiment of the electrosurgical instrument 12 shown in Figs. 3a and 3b includes the same features, characteristics, and / or optional embodiment as the embodiment of the electrosurgical instrument 12 shown in Figs. 2a to 2c except for the following differences.

[0271] The distal electrode 60 of the embodiment of Figs. 3a and 3b has a rounded outer surface for reducing the risk that the distal electrode 60 of mechanically damages tissue. For example, the edges of the distal electrode 60 are rounded and / or the distal electrode 60 includes a pointed tip which may also be rounded.

[0272] In Fig. 3b, the first isolating portion 66 and the second isolating portion 68 are not depicted to show the configuration of the first electrode 54, the second electrode 56, and the third electrode 58. For example, Fig. 3b shows that the distal section 58b is integrally formed with the longitudinal sections 58a of the third electrode 58. Further, it is apparent from Fig. 3 that the third electrode 58 forms the elongate recess in which the first electrode 54 and the second electrode 56 are arranged.

[0273] The first electrode 54 and the second electrode 56 include protrusions or flanges for interlocking the first electrode 54 and the second electrode 56, respectively, with the second isolating portion 66. Similarly, the third electrode 58 includes recesses and / or cut-outs in which the second isolating portion 68 can be provided.

[0274] The embodiment of the electrosurgical instrument 12 shown in Figs. 4a to 4c includes the same features, characteristics, and / or optional embodiment as the embodiment of the electrosurgical instrument 12 shown in Figs. 2a to 2c except for the following differences.

[0275] The electrosurgical instrument 12 does not include the third isolating portion 68, the fourth isolating portion 70, and / or the fifth isolating portion 72.

[0276] The third electrode 58 may be a solid element. However, the solid element of the third electrode 58 does not include the elongate recess. Rather, the solid element of the third electrode 58 may form a flat inner surface which is entirely covered by the second isolating portion 68. The second isolating portion 68 may form a layer of constant thickness on the inner surface of the solid element of the second electrode 58.

[0277] The longitudinal sections 58a of the third electrode 58 are not arranged on first surface 50. Rather, the longitudinal sections 58a of the third electrode 58 are formed by an outer surface of the solid element of the third electrode 58. Thus, the third radiofrequency path may extend from the first electrode 54 and the second electrode 56 to the outer surface of the solid element of the third electrode 58.

[0278] The first isolating portion 66 may again be flush with the exposed sections of the first electrode 54 and the second electrode 56 so that the exposed surface of the first isolating portion 64 is on a different level compared to the exposed surface of the second isolating portion 66. The first isolating portion 64 and the second isolating portion 66 may be integrally formed and / or are made from silicone. Thus, the first electrode 54 and / or the second electrode 56 can “float” on the second isolating portion 66 as described above.

[0279] The embodiment of the electrosurgical instrument 12 shown in Figs. 5a to 5c includes the same features, characteristics, and / or optional embodiment as the embodiment of the electrosurgical instrument 12 shown in Figs. 4a to 4c except for the following differences.

[0280] The first isolating portion 64 is a rigid isolator and / or is made from a ceramic material. The first isolating portion 64 can be attached to the exposed surface of the second isolating 66. The rigid isolator of the first isolating portion 64 may extend beyond the distal end face 76 of the first jaw 34 and / or may have a rectangular shape in a cross-sectional view.

[0281] The first electrode 54, the second electrode 56, and the distal electrode 60 can be formed by electrically conductive layers covering the rigid isolator of the first isolating portion 64.

[0282] The first electrode 54 may be arranged on a left side of the rigid isolator of the first isolating portion 64 and / or the second electrode 56 may be arranged on a right side of the rigid isolator of the first isolating portion 64. An upper side of the rigid isolator of the first isolating portion 64 that is arranged between the left side and the right side of the rigid isolator of the first isolating portion 64 may not be covered and corresponds to the gap having a distance b.

[0283] The distal electrode 60 may be formed by covering the section of the rigid isolator of the first isolating portion 64 that extends beyond the distal end face 76 with conductive layers. Thus, there is a gap on the left side of the rigid isolator of the first isolating portion 64 between the distal end of the first electrode 54 and the proximal end of the distal electrode 60 which corresponds to the distance a.

[0284] The embodiment of the electrosurgical instrument 12 shown in Figs. 6a to 6c includes the same features, characteristics, and / or optional embodiment as the embodiment of the electrosurgical instrument 12 shown in Figs. 5a to 5c except for the following differences.

[0285] The first isolating portion 64 and the second isolating portion 66 may be integrally formed as a rigid isolator, for example made from a ceramic material. The rigid isolator may essentially correspond to the layer of the second isolating portion 66 of the embodiment of Figs. 5a to 5c. For example, the rigid isolator forming a first isolating portion 64 and the second isolating portion 66 may be attached to the inner surface of the solid element of the third electrode 58.

[0286] The first electrode 54, the second electrode 56, and the distal electrode 60 are formed as conductive layers on an upper surface of the rigid isolator which forms a part of the first surface 50. The rigid isolator forming the first isolating portion 64 and the second isolating portion 66 is flush with the distal section 58b of the third electrode 58 at the distal end face 76. Thus, in this embodiment, the distal electrode 60 does not protrude from the distal end face 76. Rather, the distal electrode 60 is exposed at the distal end face 76. The conductive layers forming the first electrode 54, the second electrode 56, and the distal electrode 60 may have a shape that mimic the outline and / or the top view of the respective electrodes of the embodiments discussed above.

[0287] The third electrode 58 includes two longitudinal sections 58a which are formed as conductive layers on an upper surface of the rigid isolator forming a first isolating portion 64 and the second isolating 66. Further, the third electrode 58 includes an electrically conductive layer that is arranged on a back surface of the rigid isolator forming a first isolating portion 64 and the second isolating 66. This conductive layer may cover the entire back surface of the rigid isolator and / or may be in direct contact with the solid element of the third electrode 58.

[0288] The embodiment of the electrosurgical instrument 12 shown in Figs. 7a to 7c includes the same features, characteristics, and / or optional embodiment as the embodiment of the electrosurgical instrument 12 shown in Figs. 6a to 6c except for the following differences.

[0289] The distal electrode 60 is not arranged on the first surface 50 and / or is not electrically connected and / or mechanically attached to the second electrode 56. Rather, the distal electrode 60 is a is a solid block arranged at the distal end face 76 and arranged on the lower surface of the rigid isolator of the second isolating portion 66. A distal isolating portion 78 is provided for electrically isolating the distal electrode 60 from the solid element of the third electrode 58. The distal isolating portion 78 is a portion of the second isolating portion 66 that is separate from the rigid isolator and / or is made from silicone.

[0290] The distal electrode 60 may also include a conductive layer on the lower surface of the rigid isolator of the second isolating portion 66 that is separated by a gap from the conductive layer on the lower surface of the rigid isolator of the second isolating portion 66 that is a part of the third electrode 58.

[0291] The distal electrode 60 is not electrically connected to any of the other electrode. For supplying radiofrequency electromagnetic energy to the distal electrode 60, an RF transmission line 80 is provided which may include a cable or wire extending through the lower jaw 34. The RF transmission line 80 can be electrically coupled to the second electrode 56 providing the above-described radiofrequency paths.

[0292] The embodiment of the electrosurgical instrument 12 shown in Figs. 8a and 8b includes the same features, characteristics, and / or optional embodiment as the embodiment of the electrosurgical instrument 12 shown in Figs. 4a to 4c except for the following differences.

[0293] The first electrode 54 and the second electrode 56 are not arranged side-by- side in the middle of the first surface 50 as with the embodiments described above. Rather, the first electrode 54 is extends in the centre of the first surface 52. The second electrode 56 includes two longitudinal sections 56a which extend on either side of the first electrode 54. In this embodiment, the second electrode 56 does not extend beyond the first electrode 54 in the longitudinal direction. The longitudinal sections 56a of the second electrode 56 may be arranged in the positions and / or have to shape of the longitudinally sections 58a of the third electrode 58 which are arranged on the first surface 50.

[0294] The distal electrode 60 protrudes from the distal end face 76 and is connected to the transmission line 28 via the RF transmission line 80 which extends through the second isolating portion 66. The RF transmission line 80 may include a rigid body which supports the distal electrode 60 at the distal end face 76.

[0295] The first isolating portion 64 may be that portion of the unitary isolating portion on the inner surface of the solid element of the third electrode 58 which is arranged between the first electrode 54 and the longitudinal sections 56a of the second electrode 56. The second isolating portion 66 may be that portion of the unitary isolating portion on the inner surface of the solid element of the third electrode 58 which is arranged between the first electrode 54 and the second electrode 56 and the one hand and the third electrode 58 on the other hand.

[0296] The first radiofrequency path is between the first electrode 54 and the longitudinal sections 56a of the second electrode 56. The second radiofrequency path is between the distal electrode 60 and the distal section 58b of the third electrode 58. The third radiofrequency path is between the longitudinal sections 56a of the second electrode 56 and the longitudinal sections 58a of the third electrode 58, for example over a side surface of the second isolating portion 66.

[0297] The embodiment of the electrosurgical instrument 12 shown in Figs. 9a to 9c includes the same features, characteristics, and / or optional embodiment as the embodiment of the electrosurgical instrument 12 shown in Figs. 8a and 8b except for the following differences.

[0298] The second electrode 56, optionally the longitudinal sections 56a of the second electrode 56, are arranged on the second jaw 36, optionally exposed on the second surface 52. The first isolating portion 64 is also arranged on the second jaw 36. The first isolating portion 64 may form a layer covering the inner surface of the solid element of the fourth electrode 62 similar to the second isolating portion 66 forming a layer covering the inner surface of the solid element of the third electrode 58. Thus, in the closed position, the first isolating portion 64 electrically insulates the first electrode 54 from the second electrode 56. The second isolating portion 66 electrically insulates the first electrode 54 from the third electrode 58 and / or from the RF transmission line 80.

[0299] In this embodiment, the first radiofrequency path extends between the first jaw 34 and the second jaw 36. As the first electrode 54 and the second electrode 56 are within the perimeter of the first surface 50 and the second surface 52, the first radiofrequency path is completely confined first jaw 34 and the second jaw 34 in the closed position.

[0300] The embodiment of the electrosurgical instrument 12 shown in Figs. 10a and 10b includes the same features, characteristics, and / or optional embodiment as the embodiment of the electrosurgical instrument 12 shown in Figs. 6a to 6c except for the following differences.

[0301] The electrosurgical instrument 12 does not include a second jaw 36. Rather, the first electrode 54, the second electrode 56, the third electrode 58, the fourth electrode 62, and an isolating portion 82 are non-movably attached to the instrument shaft 30.

[0302] The electrosurgical instrument 12 does not include the distal electrode 60 and the second isolating portion 66. Rather, the isolating portion 82 is a rigid isolator having a shape similar to the second isolating portion 66 in the embodiment of Figs. 6a to 6c.

[0303] The electrosurgical instrument 12 further includes a support section 84 which can be made from electrically conductive material, such as metal. The support section 84 is attached to the shaft 30 and is provided for providing stability to the isolating portion 82. This may be helpful in case the isolating portion 82 is made from a ceramic material and, therefore, prone to breaking.

[0304] The first electrode 54, the second electrode 56, the third electrode 58, and the fourth electrode 62 are conductive layers arranged on the isolating portion 82. The first electrode 54, the second electrode 56, and the third electrode 58 are arranged on an upper surface of the isolating portion 82 and the fourth electrode 64 is arranged on a lower surface of the isolating portion 82. The upper surface is connected to the lower surface by a side surface which is not covered by an electrically conductive layer.

[0305] The first electrode 54, the second electrode 56, and the third electrode 58 are connected to the transmission line 28 on the upper surface. The fourth electrode 62 may be in electrical contact with the support section 82. The fourth electrode 62 and / or the support section 82 can be in contact with another line of the transmission line 28.

[0306] As visible in Fig. 10a, the first electrode 54 includes an edge section 54a and a central section 54b. The edge section 54a of the first electrode 54 is arranged in a distal end region of the isolating portion 82. The central section 54b of the first electrode 54 electrically connects the edge section 54a of the first electrode 54 to the transmission line 28.

[0307] The edge section 54a of the first electrode 54, the second electrode 56, and the third electrode 58 extend along an edge of the isolating portion 82 between the upper surface and the side surface. The second electrode 56 and the third electrode 58 can be considered of solely consisting of an edge section.

[0308] A maximal distance between the edge section 54a of the first electrode 54 and the second electrode 56 is smaller than the minimum distance between the central section 54b and the second electrode 56. Thus, a length of the radiofrequency path between the edge section 54a of the first electrode 54 and the second electrode 56 is smaller than a length of the radiofrequency path between the central section 54b and the second electrode 56. Thus, upon applying radiofrequency energy to the first electrode 54 and the second electrode 56, an electric current flows only between the edge section 54a of the first electrode 54 and the second electrode 56 and not between other regions of the first electrode 54 and the second electrode 56 as indicated by the arrow in Fig. 10a.

[0309] Similarly, a maximal distance between the edge section 54a of the first electrode 54 and the third electrode 58 is smaller than the minimum distance between the central section 54b and the third electrode 58. Thus, a length of the radiofrequency path between the edge section 54a of the first electrode 54 and the third electrode 58 is smaller than a length of the radiofrequency path between the central section 54b and the third electrode 58. Thus, upon applying radiofrequency energy to the first electrode 54 and the third electrode 58, an electric current flows only between the edge section 54a of the first electrode 54 and the third electrode 58 and not between other regions of the first electrode 54 and the third electrode 58 as indicated by the arrow in Fig. 10a.

[0310] This allows to provide confined radiofrequency cutting across the gap between the edge section 54a of the first electrode 54 and the second electrode 56 and across the gap between the edge section 54a of the first electrode 54 and the third electrode 58. If the first pole of the radiofrequency electromagnetic energy is applied to the first electrode 54, the second electrode 56, and third electrode 58 and a second pole of the radiofrequency electric energy is applied to the fourth electrode 62, a radiofrequency path across the side surface of the isolating portion 82 can be generated (see Fig. 10b).

[0311] As described above, the generator unit 14 may be used to selectively supply power to a pair and / or to a group of the first to fourth electrodes 54, 56, 58, and 62.

Claims

1. CLAIMS1 . An electrosurgical instrument for cutting tissue, comprising an instrument shaft including a transmission line for conveying radiofrequency electromagnetic energy, a first jaw attached to the instrument shaft, including a first surface, and defining a longitudinal direction, a second jaw attached to the instrument shaft and including a second surface, a first electrode for emitting radiofrequency electromagnetic energy, a second electrode for emitting radiofrequency electromagnetic energy, a third electrode for emitting radiofrequency electromagnetic energy, a distal electrode for emitting radiofrequency electromagnetic energy, a first isolating portion electrically isolating the first electrode from the second electrode, and a second isolating portion electrically isolating the third electrode from the first electrode, the second electrode, and the distal electrode, wherein the first jaw and the second jaw can be moved between an open position, in which the tissue can be inserted between the first surface and the second surface, and a closed position, in which the first and second surfaces are brought together to clamp tissue therebetween, wherein the first electrode and the second electrode are located on the first surface and within perimeters of the first surface and the second surface in the closed position such that a first radiofrequency path between the first electrode and the second electrode is contained between the first jaw and the second jaw in the closed position, wherein the third electrode includes a distal section, the distal section being located on an outer surface of the first jaw at a distal end thereof in the closed position, wherein the distal electrode is exposed in the closed position and configured to provide a second radiofrequency path between the distal section of the third electrode and the distal electrode, wherein a maximal length of the first radiofrequency path is smaller than a minimal length of the second radiofrequency path.

2. The electrosurgical instrument of claim 1 , wherein the distal electrode is electrically coupled to the second electrode.

3. The electrosurgical instrument of claim 2, wherein the second electrode extends beyond the first electrode in the longitudinal direction towards the distal end of the first jaw,wherein the distal electrode is connected to a distal end of the second electrode.

4. The electrosurgical instrument of claim 3, wherein the first electrode and the second electrode are separated by a gap having a width perpendicular to the longitudinal direction, wherein the distal electrode has a breadth perpendicular to the longitudinal direction, the breadth being equal to or greater than the width of the gap.

5. The electrosurgical instrument of any preceding claim, wherein the third electrode further includes a longitudinal section extending along the longitudinal direction, wherein the longitudinal section of the third electrode includes two surface sections exposed on the first surface and / or second surface, wherein the first electrode and the second electrode extend between the two surface sections of the third electrode in the closed position.

6. The electrosurgical instrument of claim 5, wherein the surface sections of the third electrode are integrally formed with the distal section of the third electrode.

7. The electrosurgical instrument of claim 6, wherein the third electrode forms a solid element including an elongate recess, wherein optionally the first isolating portion and the second isolating portion are arranged in the elongate recess forming a unitary isolating portion, and wherein the first electrode, the second electrode, and the distal electrode are arranged within and / or on the unitary isolating portion.

8. The electrosurgical instrument of any preceding claim, further comprising a third isolating portion covering at least a section of an outer surface of the third electrode being otherwise exposed in the closed position, wherein the third isolating portion forms a gap with the second isolating portion on the outer surface so that an area of the third electrode is exposed on the outer surface.

9. The electrosurgical instrument of any one of the claims 1 to 4, wherein the third electrode includes a solid element having an inner surface facing the second jaw in the closed position and an outer surface exposed in the closed position, wherein the second isolating portion covers the entire inner surface.

10. The electrosurgical instrument of claim 9, wherein the first electrode and the second electrode are arranged in and / or on the second isolating portion.

11. The electrosurgical instrument of any one preceding claim, wherein the first electrode, the second electrode, and the distal electrode are electrically conductive layers on a rigid isolator forming the first isolating portion.

12. The electrosurgical instrument of any one of the claims 9 to 11 , wherein the longitudinal section of the third electrode is arranged on the second isolating portion or arranged exposed on the second surface.

13. The electrosurgical instrument of any one of the claims 9 to 11 , wherein the outer surface of the third electrode forms the longitudinal section of the third electrode.

14. The electrosurgical instrument of any preceding claim, wherein the second isolating portion is made from silicone.

15. The electrosurgical instrument of any one of the claims 9 to 13, wherein a rigid and unitary isolator forms the first isolating portion and the second isolating portion, wherein the isolator includes an upper surface forming the first surface and a lower surface facing away from the first surface, wherein electrically conductive layers are arranged on the upper surface forming the first electrode, the second electrode, the third electrode, and the distal electrode, and wherein at least a distal edge region of the lower surface is covered by an electrically conductive layer which forms a portion of the third electrode.

16. The electrosurgical instrument of any one of the claims 9 to 13 when depending on claim 1, wherein a rigid and unitary isolator forms the first isolating portion and the second isolating portion, wherein the isolator includes an upper surface forming the first surface and a lower surface facing away from the first surface, wherein electrically conductive layers are arranged on the upper surface forming the first electrode, the second electrode, and the third electrode, wherein the electrically conductive layers are arranged on the lower surface forming the third electrode in electrical contact with the solid element,wherein the distal electrode comprises an electrically conductive element electrically isolated from the solid element by a distal isolating portion of the second isolating portion, wherein the electrosurgical instrument further includes an RF transmission line extending in the first jaw and electrically connected between the distal electrode and the transmission line.

17. The electrosurgical instrument of claim 1, wherein the third electrode includes a solid element forming a longitudinal section and the distal section, wherein the solid element of the third electrode includes an inner surface facing the second jaw in the closed position and an outer surface exposed in the closed position, wherein the second isolating portion covers the inner surface, wherein the electrosurgical instrument further includes an RF transmission line extending in the first jaw and electrically connected between the distal electrode and the transmission line.

18. The electrosurgical instrument of claim 17, wherein the RF transmission line extends within the second isolating portion, and / or the RF transmission line supports the distal electrode.

19. The electrosurgical instrument of any preceding claim, further comprising a switch unit that is switchable between a first connection state and a second connection state, wherein the switch unit is in the first connection state when the first jaw and the second jaw are in the closed position.

20. The electrosurgical instrument of claim 19, wherein, in the first connection state, the switch unit connects a first pole of the radiofrequency energy to the first electrode and a second pole of the radiofrequency energy to the second electrode, and wherein, in the second connection state, the switch unit connects a first pole of the radiofrequency energy to the first electrode, the second electrode, and the distal electrode and a second pole of the radiofrequency energy to the third electrode.

21. An electrosurgical instrument for cutting tissue, comprising an instrument shaft including a transmission line for conveying radiofrequency electromagnetic energy, a first electrode for emitting radiofrequency electromagnetic energy,a second electrode for emitting radiofrequency electromagnetic energy, a third electrode for emitting radiofrequency electromagnetic energy, and an isolating portion made from an electrically isolating and rigid material, the isolating portion having an upper surface, a lower surface, and a side surface connecting the upper surface to the lower surface, wherein the first electrode, the second electrode, and the third electrode are each formed by electrically conductive layers covering the upper surface, wherein the first electrode, the second electrode, and the third electrode each include a respective edge section that is located adjacent to the side surface, wherein a maximal length of a radiofrequency path between any two edge sections of the first electrode, the second electrode, and the third electrode is smaller than a minimal length of a radiofrequency path between any two sections of the first electrode, the second electrode outside the respective edge sections.

22. The electrosurgical instrument of claim 21, wherein the edge section of the first electrode covers a distal end region of the upper surface, wherein the first electrode further includes a central section extending between the edge section of the second electrode and the edge section of the third electrode.

23. The electrosurgical instrument of claim 21 or 22, further comprising a fourth electrode covering at least an edge portion of the lower surface.

24. An electrosurgical apparatus for cutting tissue, comprising a generator unit for generating radiofrequency, and the electrosurgical instrument according to any preceding claim, wherein the transmission line conveys the radiofrequency energy from the generator unit to the first electrode, the second electrode and / or the third electrode.

25. The electrosurgical apparatus of claim 24 when depending on claim 23, wherein the generator unit is configured to supply the radiofrequency energy to the first electrode and the second electrode for cutting tissue between the edge sections of the first and second electrodes, the first electrode and the third electrode for cutting tissue between the edge sections of the first and third electrodes, orthe first electrode, the second electrode, and the third electrode as a first pole and to the fourth electrode as a second pole for effecting tissue cutting between the upper surface and the lower surface.

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