RU2772044C2 - Electrosurgical device - Google Patents

Abstract

FIELD: medical equipment.

SUBSTANCE: electrosurgical forceps instrument contains a flexible rod defining lumen; a coaxial cable for transmission of microwave energy, located inside the lumen of the flexible rod; a bracket with a stiffness rib, mounted on the distal end of the flexible rod; a pair of brunches mounted with the possibility of rotation on the bracket with a stiffness rib, wherein the pair of brunches can move relatively to each other to open and close a gap between its opposite inner surfaces; and an actuator located inside the lumen of the flexible rod and passing from it through the bracket with a stiffness rib for functional engagement with the pair of brunches. The pair of brunches includes the first brunch containing an energy supply structure attached to its inner surface. The energy supply structure contains flexible dielectric substrate, on which the first electrode and the second electrode are formed. The energy supply structure is connected for reception of microwave energy from the coaxial cable. The first electrode and the second electrode are made with the possibility of emission of microwave energy received by the energy supply structure to the gap between the pair of brunches. A manual unit for control of the electrosurgical forceps instrument, and an electrosurgical device are disclosed.

EFFECT: providing an improved control of an electrosurgical device and, in particular, an electrosurgical forceps instrument.

24 cl, 9 dwg, 1 tbl

Description

FIELD OF TECHNOLOGY

The invention relates to electrosurgical forceps for grasping biological tissue and for supplying microwave energy to the grasped tissue for coagulation or cauterization or tissue sealing. In particular, said forceps may be used to apply pressure to close one or more blood vessels before applying electromagnetic radiation (preferably microwave energy) to seal the blood vessels. In addition, the forceps may be configured to cut tissue after coagulation or sealing, for example, using radio frequency (RF) energy or a mechanical cutting element such as a blade. The invention can be applied to forceps that can be inserted into the instrument channel of an endoscope, gastroscope or bronchoscope, or can be used in laparoscopic surgery or open surgery.

BACKGROUND OF THE INVENTION

Electrosurgical instruments are instruments that are used to deliver radio frequency and/or microwave energy to biological tissues, such as cutting biological tissue or clotting blood. RF energy and/or microwave energy is supplied to the electrosurgical instrument via a transmission line such as a coaxial cable, waveguide, microstrip or the like.

In some instances, the electrosurgical instrument may include forceps capable of delivering thermal energy to captured biological tissue located between the jaws of the forceps. For example, radio frequency (RF) energy may be applied from the bipolar electrode assembly through the jaws of the forceps. RF energy can be used to seal vessels by thermally denaturing extracellular matrix proteins (eg, collagen) within vessel walls. Heat energy can also cauterize trapped tissue and promote coagulation. Alternatively, the jaws may comprise one or more microwave emitter structures that are configured to radiate microwave EM energy into the biological tissue trapped in the jaws to seal the tissue.

Such devices are typically used at the end of minimally invasive surgical laparoscopic instruments, but may be equally applicable in other clinical procedural areas such as gynecology, endourology, gastrointestinal surgery, ENT procedures, etc. Depending on the context of use, these devices may have different physical designs, size, scale and complexity.

Current examples of minimally invasive devices capable of cutting through body tissue while achieving hemostasis include Covidien's LigaSure vessel sealing technology and Olympus' Thunderbeat platform. The LigaSure System is a bipolar forceps device that delivers current to the tissue to be sealed when pressure is applied. The Thunderbeat platform simultaneously supplies thermal energy generated by an ultrasonic source and bipolar electrical energy.

US Pat. No. 6,585,735 describes endoscopic bipolar forceps in which the jaws of the forceps are positioned to conduct bipolar energy through the tissue held therebetween.

EP 2 233 098 describes microwave tissue sealing forceps in which the jaw sealing surfaces comprise one or more microwave antennas for radiating microwave energy into tissue captured by the jaws of the forceps.

WO 2015/097472 describes electrosurgical forceps in which one or more pairs of a non-resonant asymmetric lossy transmission line design are located on the inner surface of a pair of jaws.

SUMMARY OF THE INVENTION

In the most general sense, the present invention provides various improvements for the control of an electrosurgical device and, in particular, an electrosurgical forceps instrument. In one aspect, the present invention provides an electrosurgical forceps that combines a robust jaw opening mechanism with a microwave energy delivery mechanism. In another aspect, the present invention provides a hand-held unit that combines a mechanism to control the rotation of an electrosurgical instrument with power supply and actuation of a terminal device (eg, jaw closing, blade retraction, or the like).

According to a first aspect of the invention, an electrosurgical forceps instrument is provided, comprising: a flexible shaft defining a lumen; a coaxial cable for transmitting microwave energy, located inside the lumen of the flexible rod; a bracket with a stiffening rib mounted on the distal end of the flexible rod; a pair of jaws rotatably mounted on a ribbed bracket, the pair of jaws being movable relative to each other to open and close a gap between their opposite inner surfaces; and an actuating element located inside the lumen of the flexible rod and passing from it through a bracket with a stiffening rib for functional engagement of a pair of jaws, while the pair of jaws contains the first branch containing the energy supply structure attached to its inner surface, the energy supply structure comprising a flexible dielectric a substrate comprising a first electrode and a second electrode formed thereon, wherein the power supply structure is connected to receive microwave energy from the coaxial cable, and the first electrode and the second electrode are configured to radiate microwave energy obtained by the power supply structure into the gap between the pair of jaws . This design can provide a reliable jaw opening mechanism, with the pair of jaws securely fixed relative to the distal portion of the shaft in such a way that it reduces or eliminates the risk of them tilting, for example, to one side during use. The jaws themselves can be made in the form of rigid claw-like structures, for example, from a biocompatible metal such as stainless steel. The jaws may be designed to protect the power delivery structure and thus allow the structure to be flexible, allowing it to deform as the jaws move relative to each other without affecting microwave power transmission.

In use, a pair of jaws can be positioned to capture biological tissue, such as a blood vessel, and deliver microwave energy through the gap between the inner surface of the jaws to coagulate the tissue contained in the vessel, i.e., collagen, elastin, fat, or blood, or a combination in the biological tissue, and, hence sealing the trapped vessel. Once sealed, the vessel can be cut, for example, with a blade or RF energy supplied from the same electrodes from which the microwave energy is supplied. A movable blade can be built into the jaws.

Although electrodes may be provided on only one of the jaws, it is desirable that they be provided on both jaws to evenly affect the coagulating effect of the microwave energy, which should create a better seal. Thus, the pair of jaws may comprise a second jaw located opposite the first jaw, the second jaw having an identical design to the first jaw. Thus, the pair of jaws may comprise a second jaw having a power delivery structure attached to the inner surface, so the power delivery structure comprises a flexible dielectric substrate on which the first electrode and the second electrode are formed, the power delivery structure being connected to receive microwave energy from the coaxial cable. , and wherein the first electrode and the second electrode are configured to radiate microwave energy adopted by the power supply structure into the gap between the pair of jaws. In other examples, both jaws may contain a flexible dielectric substrate, and each of them contains one electrode. The microwave energy can then be transmitted by the transmission line structure formed from the electrodes on both jaws.

The ribbed bracket may be a mounted barbed or U-shaped structure, such as attached to the distal end of a flexible rod. An axle or pivot axle can be installed between the teeth or legs of the U-shaped structure. A pair of jaws can be installed with the ability to rotate around the same axis, that is, they can rotate around a common axis.

A pair of jaws can move symmetrically about the axis. In one example, the pair of jaws may include a first jaw and a second jaw, and the actuator may include a first control cable connected to the first jaw and a second control cable connected to the second jaw. The first control cable and the second control cable are movable in a longitudinal direction relative to the bracket to open and close the pair of jaws. Each control cable may be attached to, for example attached to or attached to, the proximal portion of its respective jaw. The control cables may be rigid to provide both a pushing force and a pulling force to the pair of jaws.

The actuator may include a main control cable that extends through the lumen of the flexible rod. The main control cable may branch at its distal end to form a first control cable and a second control cable.

A retaining frame may be positioned within the proximal lumen to hold the coaxial cable and actuator in a fixed orientation relative to each other. The holding frame may have a first mounting section configured to receive and hold the coaxial cable, and a second mounting section configured to receive and hold the actuating element. A sleeve can be formed around the holding frame, the coaxial cable and the actuating element in the lumen of the flexible rod. Such an arrangement can reduce friction when manipulating the flexible rod and can help with relative sliding between the actuating element and the coaxial cable.

The holding frame may have a distal end spaced longitudinally from the stiffener bracket. In such an arrangement, the distal portion of the flexible shaft adjacent to the stiffener bracket has a larger void space and can therefore be more flexible. This can make it easier to position the instrument in awkward positions.

The first and second electrodes may be elongated conductive elements formed on a flexible dielectric substrate within the jaw. They may be parallel transmission lines and may form a planar linear structure on the inner surface. The distance of separation between the planar lines or parallel transmission lines can be chosen to provide RF cutting functionality, i.e. to ensure that the electric field generated by the application of RF energy is high enough to cut or incise/resect tissue. The parallel transfer electrodes can be positioned such that the electrodes that are opposite each other across the gap between the jaws are of opposite polarity, i.e. the positive charge of one line faces the negative charge of the opposite line. The tissue cutting action can be enhanced by opposing electric fields on two opposite surfaces when the jaws are in close proximity to each other, for example at a distance equal to or less than 1 mm, preferably equal to or less than 0.5 mm. The distance between the first and second electrodes on the jaw may be equal to or less than 0.5 mm.

The flexible dielectric substrate may include a proximal portion extending between the distal end of the coaxial cable and the proximal end of the inner surface, wherein the proximal portion deforms as the pair of jaws open and close. The proximal part can pass through a bracket with a stiffener. Thus, the coaxial cable may terminate in the lumen of the flexible rod.

A pair of conductive paths is formed on the flexible dielectric substrate to transfer microwave energy from the coaxial cable to the first electrode and the second electrode. A pair of conductive tracks may be formed on opposite sides of the flexible dielectric substrate. For example, the pair of conductive tracks may include a first conductive track electrically connected to an inner conductor of the coaxial cable and a second conductive track electrically connected to an outer conductor of the coaxial cable.

The first conductive path may be electrically connected to the first electrode, and the second conductive path may be electrically connected to the second electrode. These connections may be located at the junction on the inner surface of the jaw.

The flexible dielectric substrate may be a strip of insulating material on which an electrically conductive material is formed to provide the first electrode and the second electrode. The width of the tape may exceed the width of a pair of conductive tracks. An additional dielectric element (eg, ceramic or PTFE, or ceramic-filled PTFE) may be mounted on the inner jaw element. In order to minimize power loss in the flexible dielectric substrate and ensure that the material can withstand the stresses associated with RF cutting, i.e. maximum voltages up to 400 V or more, the material preferably has a low damping factor or tan delta, i.e. 0.001 or lower. , and has a high dielectric strength or breakdown voltage, i.e., up to 100 kV/mm or more. Polyimide or similar materials may be used.

The first jaw (or both jaws or a pair of jaws) may have a longitudinal slot formed therein to allow passage of the cutting blade. The cutting blade may be slidably mounted on the first jaw. The blade can be operated with a blade control cable that is located internally and extends from the lumen to functionally engage with the blade. The first jaw contains a cap portion, for example, at its distal end. The cover portion may be sized to hold the blade in a retracted position. The blade can be moved to the retracted position. Alternatively or additionally, the blade control cable may be operatively connected to the actuator such that movement of the blade from the retracted position pushes the pair of jaws into the closed position. These features can be used alone or in combination to prevent accidental impact on the blade.

The jaw pair may be sized to fit the instrument channel of a surgical examination device such as an endoscope, gastroscope, bronchoscope or the like.

In another aspect, the invention may provide a handpiece for operating an electrosurgical instrument, the handpiece comprising: a housing; a flexible rod extending from the proximal end of the housing; a coaxial cable passing through the lumen defined by the flexible rod, and the coaxial cable is intended for connection with an electrosurgical instrument located at the distal end of the flexible rod; a control rod extending through the lumen, and the control rod is designed to connect with an electrosurgical instrument located at the distal end of the flexible rod; actuating element mounted with the possibility of sliding on the housing; and a rotary device mounted for rotation on the body, while the coaxial cable and the flexible rod are mounted with the possibility of sliding relative to the body with an actuator and rotation relative to the body with a rotary device, and at the same time the control rod has a proximal part that is installed in a longitudinally fixed position relative to the hull. In use, the handpiece can energize an electrosurgical instrument at the distal end of the flexible shaft in combination with both a longitudinal (axial) force (through the control stem) and a rotational force (through the flexible shaft). The longitudinal force can be used to control a terminal device on the instrument, such as a pair of jaws in the forceps tool described above, or a sliding blade or needle. The force of rotation can be used to control the orientation of the tool.

The connection between the components in the handpiece is made in such a way that the flexible shaft and the coaxial cable slide against the control stem. In other words, the position of the control rod can be changed relative to the flexible rod, thus allowing physical movement at its distal end to control the tool.

The body may be of a cylindrical type which is located on an axis which is aligned with the flexible rod as it extends from the body. The axis of rotation of the rotary device can be aligned or coaxial with the axis of the housing. The rotary device may be a sleeve or a ring mounted on the outer surface of the housing. The rotary device can be held on the housing in the longitudinal (axial) direction. For example, the housing may have an annular recess in which a rotary device is installed.

The control rod can rotate relative to the body. This means that all of the following elements: flexible rod, control rod and coaxial cable rotate relative to the housing when the rotary device rotates. Due to this, twisting of the components inside the flexible shaft can be prevented. In one example, the proximal portion of the control rod may be mounted on a rotary device. If the rotator is fixed axially relative to the body, this means that the control rod will rotate with the rotator but will not slide against the body. The proximal portion may include a radial extension that extends through the flexible shaft for connection to the rotator.

The hand block may include an inner shaft that contains the proximal portion of the flexible shaft. The inner rod may be connected to the rotator to rotate with it. The inner rod may be axially slidable along a track formed within the rotator.

The actuating element may include a rod mounted to slide in the longitudinal direction (ie, in the axial direction mentioned above) within the housing. The actuator and housing may include gripping elements, such as finger rings or the like, with which the user can hold the device while operating it.

The handpiece may include a power input port on the actuator. The power input port may be a QMA connector or the like. The power input port can be connected to transmit the power it receives to the coaxial cable. Thus, the proximal end of the coaxial cable can be connected to an actuator to receive power from the power input port. The proximal end of the coaxial cable may be connected to the actuator via a swivel joint to allow relative rotation between them.

The power input port can be connected to an external coaxial cable, such as from an electrosurgical generator. The direction of connection to the power input port may be perpendicular to the direction in which the actuator slides relative to the housing. For example, the power input port may be located on the underside of the actuator.

In another aspect of the invention, a filter for blocking unwanted energy frequencies may be incorporated into the handpiece. The filter may be located in the final element so that it moves with the coaxial cable. In one example, the filter is an RF blocking circuit installed in the final element between the power input port and the coaxial cable. If the electrosurgical generator is capable of transmitting both RF and microwave energy, but the electrosurgical instrument is designed to use microwave energy only, the RF blocking circuit provides a safety mechanism to prevent misuse. This aspect of the invention may have any one or more of the features described above.

The handpiece discussed above may be used in an electrosurgical device comprising an electrosurgical generator for delivering microwave energy and a surgical examination device comprising an attachment cord for insertion into a patient's body, with an instrument channel passing through the attachment cord. The handpiece may be connected to receive microwave energy from the electrosurgical generator. The flexible shaft of the hand block can pass through the instrument channel of the surgical examination device. An electrosurgical forceps instrument, such as described herein, may be attached to the distal end of the flexible shaft of the handpiece. The hand unit actuator (which is also the instrument actuator) is connected to control the opening and closing of the electrosurgical forceps instrument. The rotary device controls the rotation of the instrument of the electrosurgical forceps relative to the instrumental channel.

The term "surgical examination device" may be used herein to refer to any surgical device equipped with an insertion tube, which is a rigid or flexible (eg, steerable) conduit that is inserted into a patient's body during an invasive procedure. The insertion tube may contain an instrumental channel and an optical channel (for example, for transmitting light for illumination and/or obtaining images of the treated area at the distal end of the insertion tube). The instrument channel may have a diameter suitable for receiving invasive surgical instruments. The diameter of the instrumental channel may be 5 mm or less.

In this document, the term "internal" means located in the radial direction closer to the center (eg, axis) of the tool channel and/or coaxial cable. The term "outer" means located in the radial direction further from the center (axis) of the tool channel and/or coaxial cable.

The term "conductive" is used in this document to refer to an electrically conductive element, unless the context requires otherwise.

In this document, the terms "proximal" and "distal" refer to the ends of an elongated probe. In use, the proximal end is closer to the generator to provide RF and/or microwave energy, while the distal end is further away from the generator.

In this description, the term "microwave" can be used in a broad sense to indicate the frequency range from 400 MHz to 100 GHz, but preferably the range from 1 GHz to 60 GHz. The specific frequencies that have been considered are: 915 MHz, 2.45 GHz, 3.3 GHz, 5.8 GHz, 10 GHz, 14.5 GHz and 24 GHz. Conversely, the terms "radio frequency" or "RF" are used herein to indicate a frequency range that is at least three orders of magnitude lower, such as up to 300 MHz, preferably 10 kHz to 1 MHz, and most preferably 400 kHz.

BRIEF DESCRIPTION OF GRAPHICS

Embodiments of the invention will now be discussed by way of example only with reference to the accompanying drawings, in which:

in fig. 1 illustrates a schematic representation of an electrosurgical system which is an embodiment of the present invention;

in fig. 2a, 2b and 2c illustrate perspective views of an instrument tip from an electrosurgical forceps instrument, which is an embodiment of the present invention;

in fig. 3a, 3b illustrate perspective views of an instrument tip from an electrosurgical forceps instrument, which is another embodiment of the present invention;

in fig. 3c is a perspective view of the jaw of the tip of the instrument illustrated in FIG. 3a and 3b;

in fig. 4a-4c are schematic views illustrating a guard mechanism that can be used to actuate the sliding blade of the tool tip illustrated in FIG. 3a and 3b;

in fig. 5 is a perspective view of an instrument tip from an electrosurgical forceps instrument, which is another embodiment of the present invention;

in fig. 6a is a perspective view of a handpiece of an electrosurgical device that is an embodiment of the present invention;

in fig. 6b is a partial sectional view of the hand block illustrated in FIG. 6a showing parts of the internal structure of the hand block;

in fig. 7a is a plan view of a circuit board that can be mounted inside the handpiece of an electrosurgical device that is an embodiment of the present invention;

in fig. 7b and 7c are perspective views of the circuit board illustrated in FIG. 7a;

in fig. 8a is a schematic side view of a power delivery structure that can be used in an electrosurgical forceps instrument embodying the present invention and comprising an insert showing an enlarged cross-sectional view through the electrode strip of the power delivery structure;

in fig. 8b is a graph showing the return loss for the power delivery design illustrated in FIG. 8a when positioned in tissue and immersed in saline;

in fig. 9a and 9b are top and bottom views of an exemplary electrode strip suitable for use in the power supply structure illustrated in FIG. 8a; and

in fig. 9c illustrates an enlarged cross-sectional view through the strip type transmission line used in the electrode strip illustrated in FIG. 9a and 9b.

DETAILED DESCRIPTION OF THE INVENTION; ADDITIONAL AND PREFERRED OPTIONS

In FIG. 1 illustrates a schematic representation of a kit electrosurgical system 100 that is an embodiment of the present invention. The system is designed to treat biological tissue (such as a tumor, lesion, or fibroma) using microwave frequency energy from the instrument tip. System 100 includes a generator 102 for controlled delivery of microwave EM energy. In some cases, generator 102 may also be capable of delivering RF electromagnetic (EM) energy. A suitable generator for this purpose is described in WO 2012/076844, which is incorporated herein by reference. The generator 102 is connected to the handpiece 106 by a connecting cable 104. The handpiece 106 may also be connected to receive a fluid supply 107 from a fluid delivery device 108, such as a syringe, although this is not required. If desired, the hand block 106 may house a tool actuator that is controlled by an actuator 109, such as a slider or thumb operated piston. For example, an instrument actuator may be used to control the jaws of the forceps instrument described herein. Other mechanisms may also be included in the hand block. For example, a blade and/or needle movement mechanism (operated by a suitable trigger on the hand block) may be provided to move the cutting blade or position the needle in the tool. The function of the hand block 106 is to combine the inlets from the generator 102, the fluid delivery device 108, and the instrument actuator, along with any other inlets that may be needed, into a single flexible shaft 112 that extends from the distal end of the hand block 106 .

The flexible rod 112 may be inserted along the entire length of the instrumental (working) channel of the surgical device 114 for inspection. The flexible shaft 112 includes an instrument tip 118 shaped to pass through the instrument channel of the surgical examination device 114 and protrude (eg, inside the patient) at the distal end of the endoscope tube. Instrument tip 118 includes a pair of jaws for grasping biological tissue and an energy delivery structure configured to emit microwave EM energy that is supplied from generator 102. Optionally, instrument tip 118 may also include a movable biological tissue cutting blade and/or a retractable hypodermic needle. injections for supplying liquid displaced from the device 108 liquid supply. As described in more detail below, the hand block 106 includes an actuator for opening and closing the jaws of the tool tip 118. The tip 106 also includes a rotation mechanism for rotating the tip 118 of the instrument relative to the instrument channel of the surgical examination device 114.

The tool tip 118 may be designed to have a maximum outer diameter suitable for passage through the working channel. Typically, the diameter of the working channel in a surgical examination device such as an endoscope is less than 4.0 mm, for example, any of the following: 2.8 mm, 3.2 mm, 3.7 mm, 3.8 mm. The length of the flexible rod 112 may be equal to or greater than 1.2 m, such as 2 m or more. In other examples, the tip 118 of the instrument may be positioned at the distal end of the flexible shaft 112 after the shaft is inserted through the working channel (and before the connecting cord is inserted into the patient's body). Alternatively, the flexible shaft 112 may be inserted into the working channel from the distal end prior to making its proximal connections. In these arrangements, the distal end assembly 118 may be larger than the operating channel of the surgical examination device 114. The system described above is one way to insert an instrument into the patient's body. Other methods are also possible. For example, the instrument may also be introduced through a catheter.

Tool tip design

In FIG. 2a is a schematic diagram showing a perspective view of an instrument tip 200 from an electrosurgical forceps instrument that is an embodiment of the present invention. The tool tip 200 includes a first jaw 202 and a second jaw 204, each of which is pivotally mounted on an axle 206 such that they are movable relative to each other to open and close a gap therebetween. The jaws may be made of metal, such as stainless steel or other biocompatible material. The axis 206 is located on the bracket 208 with a rib that protrudes from the distal end of the shaft 210 of the tool. The bracket 208 includes a mounting portion 212 that is suitably shaped to extend into and close the distal end of the instrument shaft 210. Bracket 208 may be attached to tool shaft 210 with adhesive or other suitable means (eg, ultrasonic welding). Thus, any torque applied to the tool shaft 210 can be transmitted to the tool tip 200. The tool shaft 210 may comprise a hollow tube made from any suitable material, such as PTFE.

The first jaw 202 includes a gripping portion 214 to grip biological tissue and a driving portion 216 to rotate the jaw 202 about an axis 206. The gripping portion 214 and the driving portion 216 are located at opposite ends of the jaw 202 on either side of the axis 206. Part 214 for grip is located at the distal end of the tip 200 of the tool, while the drive part 216 is located closer to the shaft 210 of the tool. Similarly, the second jaw 204 includes a gripping portion 218 and a driving portion 220 located on either side of the shaft 206. The gripping portions 214 and 218 may include serrated edges to facilitate gripping of biological tissue. The jaws 202 and 204 are rotatably mounted on the axis 206 such that the gap between the jaw gripping portions 214 and 218 can vary (ie, the gap can open and close). In use, this allows biological tissue to be gripped between the jaws 214, 218 to grip the jaws 202, 204.

The first control cable 222 is connected to the actuating portion 216 of the first jaw 202, and the second control cable 224 is connected to the drive portion 220 of the second jaw 204. The first and second control cables 222, 224 extend through the bracket 208 into the tool shaft 210 along the entire length of the shaft. 210 tools. The first and second control cables 222, 224 are connected at the proximal end of the electrosurgical instrument to a hand block (discussed in more detail below) that can be used to move the control cables back and forth along the instrument shaft 210. The control rods 222, 224 may pass through the bracket 208 through holes in the mounting portion 212 of the bracket 208. to form a watertight seal around the control cables, can be placed inside the holes. Such tubes may also be designed to prevent adhesive (eg, used during manufacture to glue bracket 208 to tool shaft 210) from accidentally getting onto control cables 222, 224 and then sticking together.

In the example shown, each of the gripping portions 216, 220 includes an opening for receiving the first and second control cables 222, 224, respectively. The first and second control cables 222, 224 each comprise a hook at their distal ends for mechanically engaging the openings of the drive portions 216 and 220, respectively. Other methods of attaching the control cables 222, 224 to the grip portions 216, 220 are also possible. For example, control cables may be glued, soldered, or welded to the grip portions.

Longitudinal movement of the first and second control cables 222, 224 along the tool shaft 210 causes the jaws 202, 204 to rotate about the axis 206, changing the clearance between the jaw gripping portions 214, 218. For example, if the first and second control cables 222, 224 are pushed along the tool shaft 210 (i.e., they are pushed towards the tool tip 200), the jaws 202, 204 are rotated so that their grip portions 214, 218 move away from each other, such thus opening the gap between the parts 214, 218 to grip. Conversely, if the first and second control cables 222, 224 are pulled along the tool shaft 210 (i.e., retracted from the tool tip 200), the jaws 202, 204 rotate so that their grip portions 214, 218 move towards each other, thereby closing gap between them.

The first and second control cables 222, 224 may move together along the tool shaft 210, or they may move independently of each other. The joint movement of the control cables can lead to symmetrical movement of the jaws relative to the longitudinal axis of the shaft 210 of the tool. This may facilitate the capture of biological tissue between the jaws. In other examples, one of the jaws may be fixed relative to the bracket 208 (ie, it does not rotate about an axis), and only one of the jaws may be rotatably mounted on the axis. In such an example, there may be only one control cable, which is connected to the pivotally mounted jaw.

In FIG. 2b is a schematic diagram showing another perspective view of the tool tip 200. In describing the features above with reference to FIG. 2a, identical reference numbers are used.

The coaxial transmission line 226 passes through the shaft 210 of the tool. Coaxial transmission line 226 is used to transmit radio frequency (RF) electromagnetic (EM) and/or microwave EM energy from a generator (eg, generator 102) to the tool tip 200. The coaxial transmission line 226 may be a conventional flexible coaxial cable and includes an inner conductor separated from the outer conductor by a dielectric material. The coaxial transmission line 226 may also include a protective outer dielectric layer. The coaxial transmission line 226 terminates in a connector 228 positioned (eg, fixed or otherwise fixed) within the tool shaft 210 . The first and second control cables 222, 224 extend along the coaxial transmission line 226 within the tool shaft 210 and pass through the holes in the connector 228 so that they can be connected to the jaws 202, 204 in the manner described above.

The first flexible microwave substrate 230 and the second flexible microwave substrate 232 are attached to the connector 228, for example, with an adhesive. In the example shown, connector 228 includes a pair of longitudinally extending protrusions to which flexible microwave substrates are attached. Flexible microwave substrates 230, 232 (which may also be referred to as electrode strips) can be made from any suitable flexible dielectric material. For example, flexible microwave substrates 230, 232 may be an RFlex microwave substrate from Rogers Corporation.

The first flexible microwave substrate 230 extends from the connector 228 through an opening in the mounting portion 212 of the arm 208. The distal portion of the first flexible microwave substrate 230 is attached to the inner surface 234 of the first jaw 202. part 212 of the liner 208 and is attached distally to the inner surface 236 of the second jaw 204. It should be noted that for purposes of illustration, the first and second flexible microwave substrates 230, 232 are not shown attached to the inner surfaces of the jaws 202, 204; they are shown in a state prior to being attached to the inner surfaces of the jaws 202, 204. Flexible microwave substrates may be attached to the inner surfaces of the jaws 202, 204 by any suitable method of attachment or fixation. For example, they may be attached with an adhesive. Alternatively, the flexible microwave substrates may be affixed to their respective inner surface with solder. In FIG. 2b illustrates a solder insert 238 applied to the underside of the second flexible microwave substrate 232. Soldering flux (not shown) is applied to the inner surface 236 of the jaw 204. The second flexible microwave substrate 232 can then be attached to the inner surface 236 by pressing the second flexible microwave substrate 232 to the inner surface 236 and heating the jaw 204 (for example, with a soldering iron tip), which causes the solder to flow and evenly distribute the solder between the second flexible microwave substrate 232 and the inner surface 236. It should be noted that for the purposes of illustration, the flexible microwave substrates 230, 232 are not illustrated in fig. 2a.

The microwave emitter structure is formed on the distal portion of each of the flexible microwave substrates 230, 232. FIG. 2b illustrates, for example, a microwave transmitter assembly 240 on the distal portion of a flexible microwave substrate 230. Each microwave transmitter assembly is coupled to receive microwave EM energy from a coaxial transmission line through conductive paths on the flexible microwave substrates. Each microwave transmitter assembly may be configured to radiate microwave EM energy into biological tissue sandwiched between jaws 202, 204. For example, one or both microwave transmitter structures may be a co-planar microstrip antenna having an active strip and a ground strip. In such a case, the flexible microwave substrate may comprise two paths: a first path connecting the inner conductor of the coaxial transmission line 226 to the active strip, and a second path connecting the outer conductor of the coaxial transmission line 226 to the ground strip. Other types of microwave emitter design are also possible.

In some cases, the tool tip 200 may comprise a single microwave emitter structure that is split between two jaws 202, 204. while a ground strip connected to the outer conductor of the coaxial transmission line 226 may be formed on the distal portion of the second flexible microwave substrate 232. In other examples, the tool tip 200 may comprise a single microwave emitter structure formed on a single jaw. In such a case, only one flexible microwave substrate may be required.

The structure of the microwave emitter and the conductive tracks on the flexible microwave substrate may be formed from a conductive material that is deposited on the flexible microwave substrate. For example, the emitter structure and conductive paths can be made of metal, which is printed on a flexible microwave substrate. Therefore, the flexible microwave substrates serve both to provide support for the microwave radiator structures and to connect the microwave radiator structures to the coaxial transmission line 226.

Because the flexible microwave substrates are flexible, they flex as the jaws 202, 204 open and close, thus allowing movement of the jaws while maintaining a connection between the microwave transmitter structures and the coaxial transmission line 226. Bending of the flexible microwave substrates 230, 232 can occur primarily near the distal portions of the flexible microwave substrates that are attached to the jaws 202, 204. This avoids high mechanical stresses in the connections between the connector 228 and the flexible microwave substrates 230, 232. the connection between the microwave emitter structures and the coaxial transmission cable will be maintained even after the jaws 202, 204 are repeatedly opened and closed. moving the flexible microwave substrates 230, 232 relative to the tool shaft to reduce mechanical stresses experienced by the connector 228 due to bending of the flexible microwave substrates 230, 232.

Thus, the tool tip 200 can be used to seal biological tissue (eg, a blood vessel) held between jaws 202, 204 by delivering microwave EM energy to the biological tissue through a microwave emitter design.

In FIG. 2c is a schematic diagram showing a perspective view of the tool tip 200 along with a length of tool shaft 210. In describing the features above with reference to FIG. 2a and 2b use identical reference numerals.

As illustrated in FIG. 2c, the first and second control cables 222, 224 are connected to a single main control cable 242 along the tool shaft 210. The first and second cables 222, 224 control can be, for example, glued, welded or soldered to the main cable 242 control. Thus, longitudinal movement of the main control cable 242 along the tool shaft 210 can be transmitted to the first and second control cables 222, 224, causing movement of the jaws 202, 204. The main control cable 242 extends along the tool shaft 210 between the first and second control cables 222, 224 and a hand block (described in more detail below). The first and second control cables 222, 224 are connected to the main control cable 242 near the distal end of the tool shaft 210 such that only one control cable (namely the main control cable 242) runs along most of the length of the tool shaft 210. This can simplify the design of the electrosurgical instrument.

Along the tool shaft 210, the coaxial transmission line 226 and the main control cable 242 enter into a cable clamp 244 having a first channel containing a portion of the coaxial transmission line 226 and a second channel containing a portion of the main control cable 242. The cable clamp 244 serves to fix the transverse positions of the coaxial transmission line 226 and the main control cable 242 relative to each other while allowing the main control cable 242 to move longitudinally along the tool shaft 210. Therefore, the cable clamp 244 prevents the coaxial transmission line 226 and the main control cable 242 from becoming entangled or twisted within the tool shaft 210, which can affect the accuracy with which the opening and closing of the jaws can be controlled. Where other cables (eg, blade control cable) or channels (eg, fluid channel) are used, cable clip 244 may also include additional channels to hold additional cables and/or channels. The rope clamp may be made of plastic, for example it may be extruded from polyetheretherketone (PEEK).

The rope clamp 244 itself may be inside a tube 246 (eg, PEEK tube). The tube 246 may have a split 248 along its length to facilitate insertion of the cable clamp into the tube 246. The tube 246 may act as a spacer between the cable clamp 244 and the inner surface of the tool shaft 210 to prevent movement of the cable clamp 244 within the tool shaft 210. This can help avoid lag when pushing or pulling the main control cable 242 to move the jaws 202, 204.

The distal ends of the cable clamp 244 and tube 246 are spaced from the tool tip 200 by a predetermined distance. Therefore, the instrument shaft 210 includes a distal portion 250 between the instrument tip 200 and the distal ends of the cable clamp and tube 246 where there is no cable clamp 244 or tube 246. The cable clamp 244 and tube 246 can extend along the instrument shaft 210 for most of its length. or the entire length between their distal ends and the hand block. Therefore, the distal portion 250 of the instrument shaft 210 may be more flexible than the rest of the instrument shaft 210. This may improve the maneuverability of the instrument shaft 210 as it may allow the distal portion 250 to pass through highly curving channels. The absence of the cable clamp 244 and tube 246 in the distal portion 250 also serves to provide space for connection between the first and second control cables 222, 224 and the main control cable 242. In some embodiments of the invention, the length of the distal portion 250 of the shaft 210 of the instrument may be 150 mm.

In FIG. 3a and 3b illustrate perspective views of another instrument tip 300 of an electrosurgical instrument in accordance with the invention. The tool tip 300 includes a first jaw 302 and a second jaw 304 rotatably mounted on an axis 305. The first and second jaws 302, 304 comprise gripping portions 306, 308, respectively, for gripping biological tissue therebetween. Similar to the instrument tip 200 described above, the jaws 302, 304 also include actuating portions to which control cables (not shown) are attached to open and close the jaws.

The first jaw 302 includes a blade 306 that is movable along a longitudinally extending slot 308 in the jaw 302. The blade is movable back and forth along the slot 308 by means of a control cable (not shown) attached to the blade 306 and extending through the tool shaft to the hand block. The first jaw 302 further includes a cap 310 at its distal end into which the blade 306 can be retracted without being exposed. Thus, when not in use, blade 306 can be retracted into cover 310 to avoid unintentional cutting of any tissue. Blade 306 can be moved to a retracted position where it is hidden by cover 310.

The second jaw 304 includes a microwave emitter structure 312 applied to a flexible microwave substrate 314 in a manner similar to that described above for the tool tip 200. The microwave emitter structure 312 may be configured to radiate microwave EM energy into tissue sandwiched between the jaws 302, 304. The second jaw 304 further includes a slot 316 to receive a blade 306. The slot 316 extends through a portion of the microwave emitter structure 312 and the flexible microwave substrate 314, so that the active electrode 315 is divided into two pins as illustrated in FIG. 3c, which is a schematic representation of the second jaw 304. The slot 316 on the second jaw 304 is aligned with the slot 308 on the first jaw so that when the jaws are brought together, the blade 306 can be received in the slot 316 of the second jaw 304 and moved back and forth along the slot 316. Both slots 308 and 316 are oriented in the longitudinal direction (ie, along the axis of the tool shaft). Blade 306 includes a cutting edge 318 that faces inward toward axis 305. Thus, biological tissue held between jaws 302, 304 can be cut by pulling the blade along slot 308 toward axis 305. The maximum length of cut that can be achieved with using the tip 300 of the tool is determined by the length of the jaws 302, 304 and slots 308 and 316, as they determine the range of motion of the blade 306. Longer slots 308, 316 may allow longer cuts to be made.

Next, an exemplary use of the tool tip 300 will be described. First, the blade 306 is placed in a retracted (most distal) position to be hidden by the cover 310. The jaws 302, 304 are then opened using the control cables. Next, the biological tissue to be cut is placed between the jaws 302, 304 and the jaws are closed in this manner. that biological tissue is captured between them. Then, using the microwave emitter structure 312, microwave EM energy is applied to the biological tissue to cauterize the biological tissue. Thereafter, the blade 306 can be pulled along the slot 308 toward the axis 305 to cut the biological tissue held between the jaws 302, 304. Because the biological tissue was cauterized prior to cutting, bleeding can be avoided.

In FIG. 4a, 4b and 4c are schematics illustrating a guard 400 that can be used to move a blade 306 along a slot 308 in the tool tip 300. Due to the mechanism 400, the blade 306 is always subject to a pushing force so that it is displaced to the retracted position where it is hidden by the cover 310. The safety mechanism 400 may be located inside the tool shaft near the distal end of the tool shaft where the tool tip is attached. For purposes of illustration, the tool shaft is not illustrated in FIG. 4a, 4b and 4c.

In FIG. 4a, 4b, and 4c illustrate an electrosurgical instrument coaxial transmission line 402 for transmitting microwave EM energy to the instrument's handpiece. Also illustrated are first and second control cables 404 and 406 for opening and closing the instrument tip jaws described above. The third control cable 408 passes through the shaft of the tool to move the blade 306 back and forth along the slot 308. Movement of the third control cable 408 in the longitudinal direction along the tool shaft causes the blade 306 to move along the slot 308. The safety mechanism 400 includes a proximal ring 410 and a distal ring 412, separated by a coil spring 414. A coaxial transmission line 402 passes through the proximal and distal rings 410, 412 and the coil spring 414. The distal ring 412 is located closer to the instrument tip than the proximal ring 410. Both the proximal and distal rings 410, 412 have three grooves : one to receive the first control cable 404, one to receive the second control cable 406, and one to receive the third control cable 408. In FIG. 4b and 4c illustrate enlarged views of the proximal and distal rings 410, 412, respectively.

The first and second control cables 404, 406 are attached to the proximal ring 410 such that they are fixed relative to the proximal ring 410 (ie, they cannot slide in their respective grooves relative to the proximal ring). For example, the first and second control cables 404, 406 may be glued or soldered to the proximal ring 410. However, the first and second control cables 404, 406 are not secured relative to the distal ring 412, so that they can slide in their grooves relative to the distal ring 412. And on the contrary, the third control cable 408 is not fixed relative to the proximal ring 410, so that it can slide in its groove relative to the proximal ring 410. However, the third control cable 408 is fixed relative to the distal ring 412, so that it cannot slide in its groove relative to the distal ring . The proximal and distal rings 410, 412 are not fixed relative to the coaxial transmission line 402 and can slide relative to the coaxial transmission line 402.

The safety mechanism 400 may be positioned such that the spring 414 provides a compressive force that pushes the proximal ring 410 and the distal ring 412 apart. The longitudinal movement of the proximal ring 410 in the proximal direction is limited by the jaws. When the jaws are closed, the proximal ring 410 cannot move further back along the shaft because it is attached to the first and second control cables 404, 406. Without application of an external force to the third control cable 408, the separation of the proximal ring 410 and the distal ring 412 determined by the spring may be such that the blade is further held in the cover when the proximal ring 410 is in this position. The blade can then be moved by applying force to the third control cable 408 which compresses the spring to allow the distal ring 412 to move closer to the proximal ring 410.

Likewise, the longitudinal movement of the distal ring 412 in the distal direction may be limited by a cap, which is the physical block for the distal movement of the blade. When the blade is held in the lid, the distal ring 412 cannot move further forward along the shaft because it is fixed to the third control cable 408. In this case, the jaws can still be opened by applying force to the first and second control cables 404, 406 which compress the spring to allow the proximal ring 410 to move closer to the distal ring 412.

It should be noted that alternative safety mechanisms may be used to shift the position of the blade and/or jaws. For example, in the case of a safety mechanism that shifts only the position of the blade 306, the proximal ring 410 may be fixed relative to the coaxial transmission line 402, and the first and second control cables 404, 406 may be slid relative to the proximal ring 410. The distal ring 412 may be configured such that as described above for the safety mechanism 400. The compression of the spring 414 then acts as described above to move the blade 306 towards the retracted position, but applies any force to the first and second control cables 404, 406 to move the position of the jaws 302, 304.

The tool tip of the electrosurgical instrument according to the invention may be configured to perform functions in addition to sealing the vessel. For example, the tip of the instrument may include an auxiliary radio frequency (RF) dissector element mounted on its distal tip. In FIG. 5 illustrates an example of an instrument tip 500 in accordance with the invention, comprising a pair of jaws 502, 504 and an RF dissector element 506 mounted at the distal end of the jaw 502. The RF dissector element 506 is a bipolar structure that includes an active electrode mounted in a ceramic tube 508, and a return electrode which may be formed on or integral with the jaw 502 in close proximity to the ceramic tube 508. A groove is provided on the top surface of the jaw 502 to receive the ceramic tube 508. The dissector element 506 is connected to the RF transmission wire 510, which extends through the instrument shaft 512 and is configured to transmit RF EM energy from an RF EM energy generator located at the proximal end of the electrosurgical instrument. For example, the RF transmission wire 510 may be a copper wire contained in a PTFE sheath.

The RF dissector element 506 can be used for fine, bloodless cutting and dissection of tissue. In the arrangement illustrated in FIG. 5, RF dissector element 506 is a leading edge that protrudes beyond the distal end of jaw 502. This position may allow both lateral and end incisions to be made. In dry field treatment situations (i.e., in the absence of saline or other electrically conductive fluid), it is desirable that the return electrode be in close proximity to the active electrode, which is located on the RF dissector element 506. The area ratio of the exposed electrodes in contact with the tissue is also important. to ensure that current flows in a desired manner that causes maximum current density at the leading edge of the RF dissector element 506.

Although in FIG. 5, RF dissector element 506 is shown at the distal end of jaw 502 and can be mounted in various orientations or locations on the distal end assembly, such as vertically, horizontally, at an angle, on one side, and on either jaw.

Hand block design

In FIG. 6a illustrates a handpiece 600 that can be used with an electrosurgical device that is an embodiment of the present invention. The hand block 600 includes a housing 602 and a drive portion 604. The housing 602 includes a hollow cylindrical portion 606 in which a shaft 608 of the drive portion 604 is slidably engaged. Housing 602 also includes a rotator 610 that is rotatably coupled to barrel 606. Drive 604 is connected to an inner shaft 628 that extends through barrel 606 and rotator 610 and protrudes from the distal end of rotator 610. Inner rod 628 moves in the longitudinal direction with the rod 608, but can rotate relative to it. The tool shaft 612 exits the hand block 600 at the distal end of the inner shaft 628. For example, the tool shaft 612 may be the tool shaft 210 described above, which is connected to the tool tip at its distal end. Tool shaft 612 is rotatably connected to inner shaft 628.

The drive portion 604 is slidable longitudinally relative to the body 602 along its shaft 608 between two positions: a closed position, in which a segment of the shaft 608 is inside the cylinder 606, and an open position, in which the segment of the shaft 608 is outside the cylindrical portion 606. In FIG. 6a illustrates a hand block 600 with the drive portion 604 in the open position. The total range of movement of the drive portion 604 relative to the housing 602 may be about 35 mm. The longitudinal direction of movement of the drive portion 604 relative to the body 602 is aligned with the longitudinal axis of the tool shaft 612, which extends from the inner shaft 628. The shaft 608 may include one or more grooves 614 that engage with protrusions (not shown) within the cylindrical portion 606 to to prevent rotation of the drive portion 604 relative to the housing 602. The housing 602 includes a pair of finger rings 614, 616, and the drive portion 604 includes a thumb ring 618 that can be used to facilitate a user's grip of the device while moving the drive portion 604 relative to the housing 602. further comprises an input connector 620 for connecting a connecting cable (eg, connecting cable 104) that connects the handpiece 600 to a generator (eg, generator 102). The input connector 620 may, for example, be a QMA connector or any other suitable connector for interfacing with the generator.

In FIG. 6b illustrates a sectional view of the hand block 600, omitting some parts to show the internal structure of the hand block. In describing the features above with reference to FIG. 6a, identical reference numbers are used.

Input connector 620 is electrically connected to circuit board 622 located in stem 608 of drive portion 604. Input connector 620 forms a substantially right angle with circuit board 622 so that it is oriented along a direction that is substantially perpendicular to the direction of relative movement between the drive portion and the housing 602. Thus, the cable that is connected to the input connector 620 may not be exposed to the user. Output connector 624 is attached to the edge of circuit board 622. Circuit board 622 includes circuitry that is configured to block input of RF EM energy into input connector 620 and transmit any microwave EM energy input into connector 620 to output connector 624. Output connector 624 electrically connected to the coaxial transmission line 626 via a mating connector 627 on the coaxial transmission line 626. The coaxial transmission line 626 extends through the hand block 600 and enters the tool shaft 612 at the distal end of the hand block 600. The coaxial transmission line 626 may, for example, correspond to the coaxial line 226 described above, which is for transmitting microwave EM energy to the handpiece of the instrument. Thus, circuit board 622 provides a safety mechanism that prevents inadvertent transmission of RF EM energy to coaxial transmission line 626. Circuit board 622 is described in more detail below.

The electrical connection between output connector 624 and coaxial transmission line 626 is rotatable, that is, it allows the coaxial transmission line to rotate about its axis relative to output connector 624. Suitable connectors that allow rotation of electrical connections include QMA connectors, micro coaxial ; MCX) connectors and micro-miniature coaxial (MMCX) connectors.

As shown in FIG. 6b, the inner shaft 628 extends through both the barrel 606 and the rotator 610 of the body 602 and is slidable in the longitudinal direction with respect to both the barrel and the rotator. The distal end of the inner shaft 628 protrudes from the rotary device 610. The length of the protrusion depends on the position of the shaft 608 of the drive section 604. The inner shaft 628 is connected at the proximal end to the shaft 608 of the drive section 604 through an annular recess 630 around the outer surface of the inner shaft 628, which is in engagement with a radial protrusion 632 on the inner surface of the shaft 608. The connection between the shaft 608 and the inner shaft 628 prevents movement of the inner shaft 628 in the longitudinal direction relative to the shaft 608, but allows the inner shaft 628 to rotate about its axis relative to the shaft 608. Therefore, the inner shaft 628 can move in the longitudinal direction back and forth relative to the housing 602, moving the drive portion 604 relative to the housing 602.

The inner shaft 628 may include a proximal portion 631 having a resonator to hold the connector 627 of the coaxial transmission line 626 in a position in which it will remain securely connected to the output connector 624 on the circuit board 622. In addition, the connector 627 on the coaxial transmission line 626 may include a protrusion 633 that is configured to engage with a slot in the proximal portion 630 of the inner shaft 628 to prevent movement of the connector 627 relative to the inner shaft 628. For example, the protrusion 633 may be a nut that is part of the connector 627 or attached (eg, soldered) to the specified connector. In addition, the protrusion 627 may be configured to rotate the connector 627 to the inner shaft 628 such that the rotation of the inner shaft 628 causes the connector 627 to rotate.

Coaxial transmission line 626 passes through the inner shaft 628, and at its distal end it enters the shaft 612 of the tool. The length of the shaft 612 of the tool is located inside the distal part 634 of the inner shaft 628, and it is attached to the inner shaft 628. Thus, the longitudinal and rotational movement of the inner shaft 628 can be transmitted to the shaft 612 of the tool. For example, the tool shaft 612 can be bonded with an epoxy to the distal portion 634 of the inner shaft 628. Adhesion between the tool shaft 612 and the inner shaft 628 can be improved by roughening the surface of the tool shaft 612 prior to application of the epoxy. In some cases, the length of the segment of the shaft 612 of the tool, located in the distal part 634, may be about 22 mm to ensure good adhesion.

The rotator 610 is connected to the cylindrical portion 606 so that it can rotate relative to the cylindrical portion about the longitudinal axis of the hand block 600. In the example shown, the rotator 610 has a proximal portion 642 with an annular recessed channel 644 that receives a radially inward projection 646 on the cylindrical part 606.

Inner rod 628 passes through rotator 610 and engages rotator 610 such that it can slide relative to rotator 610 along its length but cannot rotate relative to rotator 610 (i.e. rotator 610 and inner rod 628 are locked). regarding the possibility of rotation relative to each other). This can be achieved by any kind of interaction that conveys rotational motion. For example, there may be one or more longitudinally oriented cooperating engagement elements (e.g., grooves and teeth) formed on the outer surface of the inner shaft 628 and the inner surface of the rotator 610. The engagement elements may respectively engage with each other to cause the inner shaft to rotate. shaft 628 as the rotator 610 on the cylindrical portion 606 rotates. This in turn causes the instrument shaft 612, which is attached to the inner shaft 628, to rotate, such that the tool tip attached at the distal end of the instrument shaft 612 can also rotate. However, since the inner shaft 628 is not rotatably coupled to the driving portion 604, the driving portion 604 is not rotated when the rotary device 610 is rotated. that the rotation of the rotator 610 causes the inner rod 628 to rotate about its longitudinal axis.

A section of the main control cable 636 is located in the inner shaft 628 and exits the hand block through the shaft 612 of the tool. The main control cable 636 may be used to open and close jaws on an instrument tip attached to the distal end of the instrument shaft 612. For example, the main control cable 636 may correspond to the main control cable 242 described above. The proximal end of the main control cable 636 is fixed relative to the body 602 of the hand unit 600. Therefore, movement of the body 602 relative to the drive portion 604 may cause the main control cable 636 to move longitudinally along the tool shaft 612. This is because the longitudinal position of the tool shaft 612 is fixed relative to the drive portion 604 (via an inner shaft 628 which is connected at one end to the drive portion 604 and at the other end to the tool shaft 612), while the main control cable 636 can be moved with body 602 with respect to the drive portion 604 and hence the shaft 612 of the tool.

Thus, the user can move the drive portion 604 relative to the body 602 to move the main control cable 636 back and forth relative to the instrument shaft 612 and control the opening and closing of the jaws on the instrument tip attached at the distal end of the instrument shaft 612.

There are several possible ways to secure the proximal end of the main control cable 636 relative to the body 602 of the hand block 600. In the example shown, the block 638 is attached to the proximal end of the main control cable 636. Block 638 may, for example, be a piece of metal that is soldered or welded to the proximal end of the main control cable 638. The pulley 638 may be configured to fit inside a holder (not shown) that is rigidly connected to the rotator 610 such that the longitudinal movement of the body 602 relative to the drive portion 604 is transmitted to the pulley 638 (and hence the main control cable 636) via the holder. . The holder can be connected to the rotator 610 through a hole in the side wall of the inner rod 628.

A portion of the main control cable 636 in the inner stem 628 may be contained in a protective tube 640. The protective tube may be made from any suitable material (eg, PTFE) and may be designed to prevent the main control cable 636 from bending when the hand unit 600 is open. alternatively, a metal tube may be soldered or welded to the main control cable 636 to achieve the same effect.

The relative linear movement between the drive portion 604 and the housing 602 directly controls the linear movement of the main control cable 636 relative to the tool shaft 612. This may allow the user to fine-tune the opening and closing of the jaws on the tool tip at the distal end of the tool shaft 612. In addition, the configuration of the hand block 600 allows the user to comfortably hold the hand block 600 with one hand and control the opening and closing of the jaws with one hand (by inserting the fingers of one hand into the finger rings 614, 616, 618). The user can also simultaneously rotate the rotator 610 with the other hand to rotate the tool tip. The orientation of the input connector 620 can ensure that any cable connected to the input connector 620 does not interfere with the user's work with the handheld unit 600. Thus, the user does not need to hold the handheld unit 600 in an awkward position to place the cable, which could put strain on the wrist. user.

Circuit board with RF blocking circuit

In FIG. 7a illustrates a schematic plan view of the top surface of a circuit board 700 that may be present in the handpiece of an electrosurgical instrument that is an embodiment of the present invention. For example, the circuit board 700 may correspond to the circuit board 622 described above in connection with the hand block 600. FIG. 7b illustrates a perspective view of the bottom surface of the circuit board 700, and FIG. 7c illustrates a perspective view of the top surface of the circuit board 700.

The circuit board 700 includes an input connector 702 mounted on its bottom surface and an output connector 704 mounted near the edge of the circuit board 700. The circuit board 700 includes an RF blocking circuit on its upper surface that is configured to transmit microwave EM energy from the input connector 702 to output connector 704 while blocking the transmission of any RF EM energy from input connector 702 to output connector 704.

As illustrated in FIG. 7a, the RF blocking circuit on the circuit board 700 includes a main stripline 706. The inner (active) conductor of the input connector 704 is electrically connected to the main stripline 706 at connection point 708. An opening may be provided in the circuit board 700 so that the inner conductor of the input connector 704 can be electrically connected to the main waveguide 706. The main waveguide 706 is connected at the distal end to the inner conductor 710 of the output connector 704. separating the main strip waveguide 706 into the first part 712 and the second part 714. The first and second parts 712, 714 of the main strip waveguide 706 are connected by an RF blocking capacitor 716, which is configured to block the transmission of RF EM energy along the main strip waveguide 706 to the output connector 704. For example, the capacitance of RF blocking capacitor 716 may be 3.3 pF.

Each of the top and bottom surfaces of the circuit board 700 contains a respective ground plane 718 and 720. Ground planes 718 and 720 may, for example, be layers of metal that cover most of the top and bottom surfaces, respectively. The main strip waveguide 706 is isolated from the ground plane 718 by an insulating barrier 722 that surrounds the main strip waveguide 706. The ground plane 720 on the bottom surface is electrically connected to the outer shell of the input connector 702. connector 704 is electrically connected to both ground planes 718 and 720. The outer shell of input connector 702 may be configured to be connected to the ground of a generator (eg, generator 102 via connection cable 104). Thus, the ground planes 718, 720 and the outer shell of the output connector 704 can be grounded through the generator connected to the input connector 702.

The RF blocking circuit on the top surface may further comprise a plug 724 that branches from the main stripline waveguide 706 in front of the RF blocking capacitor 716. A microwave shorting capacitor 726 may be located on the plug 724 at a distance of approximately a quarter wavelength (relative to the wavelength of the used microwave EM energy) from the main waveguide 706. The microwave shorting capacitor 726 is connected between the plug 724 and the ground plane 718 and acts as a short to ground for microwave EM energy. Thus, the stub appears as an open microwave circuit on the main stripline waveguide 706. The microwave shorting capacitor 726 may have a capacitance similar to that of the RF blocking capacitor 716. A terminating resistor 728 is connected downstream of microwave shorting capacitor 726 between plug 724 and ground plane 718. Any RF EM energy supplied to the RF blocking circuit must pass to terminating resistor 728 where it can be dissipated as the RF EM energy is blocked from traveling along the main strip waveguide. 706 with an RF blocking capacitor 716. The load resistor 728 can be set to cause the oscillator connected to circuit board 700 to generate an error signal if RF EM energy is inadvertently applied to the RF blocking circuit. The load resistor 728 may, for example, be about 9.1 ohms.

The RF blocking capacitor 716 and the microwave shorting capacitor 726 can be selected to provide sufficiently low impedance at microwave frequencies (eg, 5.8 GHz) and sufficiently high impedance at RF frequencies (eg, 400 kHz). In other words, capacitors 716 and 726 should be close to a short circuit at microwave frequencies and close to an open circuit at RF frequencies. Thus, the RF blocking circuitry can ensure that the microwave energy is properly matched to the output 704. The circuit board 700 can be made from any suitable circuit board material. For example, the circuit board may be made of RO3006 laminate from Rogers Corporation. The dielectric constant of this material is about 6, which allows miniaturization of the circuit board design 700.

The circuit board 700 may further include a series of through connections 730 located along the main stripline 706 and plug 724 to reduce interference caused by spurious radiation. Through connections 730 may be through holes in a circuit board. To further reduce spurious radiation, a protective housing (eg, made of metal) may be placed over the top surface of circuit board 700. In addition, circuit board 700 may be completely enclosed in a protective housing. In the case where a handpiece (e.g., handpiece 600) contains a circuit board 700, it may be possible to shield the circuit board 700 by applying a metal coating to the inside surface of the handpiece so that the circuit board 700 is partially or completely surrounded by the metal coating when it is installed in the hand block.

The circuit board 700 serves as an additional safety mechanism to prevent RF EM energy from being accidentally applied to the electrosurgical instrument. The circuit board 700 also prevents RF EM energy from being transmitted from the generator to the handpiece of the instrument where unwanted RF EM energy could harm the patient. Because the circuit board is directly integral with the handpiece of the electrosurgical instrument, it is effective even in situations where the user misuses the electrosurgical instrument (eg, when the user has connected the wrong generator to the handpiece). It should be noted that circuit board 700 is shown as an example only, and circuit boards having alternative configurations may also be used to achieve the same effect.

In FIG. 8a illustrates a schematic side view of one example of an energy delivery structure 800 that can be used in an electrosurgical forceps instrument of the type described above, with both jaws 802 positioned to deliver energy to tissue trapped therebetween. Each jaw receives energy from a coaxial cable 808 through a corresponding flexible electrode strip 804, which can be passed through a distal bracket (not shown) as described above.

In this example, the flexible electrode strip 804 transmits power in the longitudinal direction with a strip-type transmission line design, the cross section of which is shown in the enlarged inset of FIG. 8a. The stripline transmission comprises a flexible planar structure comprising a central conductive layer 822 separated from a pair of ground plane layers 818, 826 of opposite sides by a pair of flexible dielectric layers 820, 824. The ground plane layers on their outer surfaces (i.e., side-facing surfaces) from the central conductive layer 822) are covered with respective dielectric (insulating) coating layers 816, 828.

The proximal end of each flexible electrode strip 804 is connected to the distal end of the coaxial cable 808 in a connector 806. The connector 806 may be a sleeve or tube that lies over the overlap area between the flexible electrode strips 804 and the coaxial cable 808. The coaxial cable 808 includes an inner conductor 810, separated from the outer conductor 812 by a dielectric material 811.

Inner conductor 810 and dielectric material 811 protrude beyond the distal end of outer conductor 812. Inner conductor 810 is electrically connected to a conductive contact block 814, which in turn is electrically connected to an exposed portion of center conductor 822 within each flexible electrode strip 804. Center conductor may be opened by cutting, etching, or otherwise removing a section of the first cover layer 816, the bottom layer 818 of the ground plane, and the first flexible dielectric layer 820 in contact with the block 814 conductive contact.

Meanwhile, the outer conductor 812 is electrically connected to one of the layers of the ground plane, for example, by opening the distal part of the upper ground layer 826 and bringing it into electrical contact with the outer conductor 812, for example, through a conductive layer on the inner surface of the connector 806. Layers 818, 826 the ground planes may be electrically connected to each other by one or more through connections (not shown) filled with conductive material that extends through the flexible dielectric layers 820, 824 in the side regions of the stripline where there is no center conductor. For example, the width of the center conductor layer 822 may be less than the width of the ground plane layers 820, 824 along the length of the stripline. This means that the ground plane layers 820, 824 extend widthwise past the side edge on the center conductor layer on one or both sides thereof. Through connections can be formed between the layers 820, 824 of the ground plane in this side zone.

At the distal end of the stripline, the center conductor layer 822 and one or both of the ground plane layers may be exposed to form the electrodes described above.

The use of a stripline in the electrode strips provides a more isolated power transfer design than the microstrip described above. With a stripline, the energy is almost entirely concentrated between the two ground plane layers 820, 824 so that no signals are exposed to the outer surfaces. The advantage of this arrangement is that the presence of saline or other conductive fluid around the distal tip of the instrument does not adversely affect energy transfer. This advantage is demonstrated by the graph shown in Fig. 8b, where line 830 indicating return loss in the presence of saline is very similar to line 832 indicating return loss in tissue. This is further supported by the breakdown by energy absorption in each case:

Model Energy absorbed by tissue Energy absorbed by saline Saline solution not present 66.0% - Saline solution present 61.8% 0.56%

Table 1. Energy absorption with and without saline

In FIG. 9a and 9b illustrate top and bottom views of an exemplary electrode strip 900 suitable for use in the power delivery design illustrated in FIG. 8a. The electrode strip 900 includes an elongated flat strip line 904 having a profiled distal and proximal ends where it connects to a respective jaw and coaxial cable, respectively.

In FIG. 9c illustrates an enlarged cross-sectional view of transmission stripline 904. The transmission line structure itself is formed from a pair of flexible, layered dielectric substrates 915, 916. Each layered dielectric substrate includes a flexible dielectric (eg, polyimide) layer containing a conductive material, such as copper, layered on one or both of its surfaces. The laminated conductive material may be shaped into a desired shape on a substrate by etching or the like.

In this example, the top layered substrate 915 includes a first dielectric layer 918 and a top layer 916 of the ground plane. The bottom layered substrate 919 includes a second dielectric layer 922, a center conductor layer 920, and a bottom ground plane layer 924. The top layer substrate 915 and the bottom layer structure are bonded together, for example with a (non-conductive) adhesive 928, such that the center conductor layer 920 is sandwiched between the first and second dielectric layers 918, 922. The center conductor layer 920 has a narrower width than the top and the lower layers 916, 924 of the ground plane of the stripline transmission. The top laminate substrate 915 may be a single-sided laminate or may be formed from a double-sided laminate by fully etching away one of the conductive surfaces.

The transmission line is located between a pair of outer cover layers 914, 926 made of a flexible insulating material such as polyimide. The cover layer 914, 926 may be adhered to an adjacent surface of the strip line. Although not shown in FIG. 9c, the top and bottom ground plane layers 916, 924 are electrically connected by a series of vias 930 formed at the proximal and distal ends of the electrode strip in a region spaced in the width direction from the center conductor layer 920. Through connections pass through the first and second dielectric layers 918, 922 between the upper and lower layers 916, 924 of the ground plane and carry a conductive material to create an electrical connection.

The proximal end of the electrode strip is configured to connect the conductive layers to the coaxial cable. On the top surface of the electrode strip 900 (shown in Fig. 9a), the top cover layer 914 is removed to expose a portion 906 of the ground plane top layer 916, which in turn is electrically connected to the outer conductor of the coaxial cable, for example, in a manner similar to that described above. with reference to FIG. 8a. On the bottom surface of the electrode strip 900 (shown in FIG. 9b), the bottom cover layer 926, the bottom ground plane layer 924, and the second dielectric layer 922 are removed to expose a portion 908 of the center conductor layer 920, which is in turn electrically connected to the inner conductor. coaxial cable, for example, in a manner analogous to that described above with reference to FIG. 8a. In practice, conduit 910 is removed from the three layers mentioned above to receive a length of inner conductor that protrudes from the distal end of the coaxial cable. The center conductor layer 920 does not extend to the proximal end of the electrode strip 900 in order to reduce or minimize energy losses in this connection.

The distal end of the electrode strip 900 is configured to provide an energy delivery electrode in a corresponding jaw. On the top surface of the electrode strip 900 (shown in Fig. 9a), the top cover layer 914 terminates in front of the distal end to expose a portion 902 of the ground plane top layer 916, which in turn is electrically connected to its corresponding jaw. On the bottom surface of the electrode strip 900 (shown in FIG. 9b), the bottom cover layer 926, the bottom ground plane layer 924, and the second dielectric layer 922 terminate before the distal end to expose the portion 912 of the power-supplying center conductor layer 920. The open portion is spaced from the edges of the first dielectric layer 918 to control the shape of the radiated field.

Claims (48)

1. An electrosurgical forceps instrument, comprising: flexible rod that defines the clearance; a coaxial cable for transmitting microwave energy, located inside the lumen of the flexible rod; a bracket with a stiffening rib mounted on the distal end of the flexible rod; a pair of jaws rotatably mounted on a ribbed bracket, the pair of jaws being movable relative to each other to open and close a gap between its opposite inner surfaces; and an actuating element located inside the lumen of the flexible rod and passing from it through a bracket with a stiffening rib for functional engagement with a pair of jaws, wherein the pair of jaws includes a first jaw containing an energy supply structure attached to its inner surface, the energy supply structure comprising a flexible dielectric substrate on which the first electrode and the second electrode are formed, wherein the power supply structure is connected to receive microwave power from the coaxial cable, and wherein the first electrode and the second electrode are configured to radiate microwave energy received by the power supply structure into a gap between the pair of jaws. 2. An electrosurgical forceps tool according to claim 1, characterized in that the pair of jaws is installed with the possibility of rotation around a common axis. 3. An electrosurgical forceps tool according to claim 1 or 2, characterized in that the pair of jaws includes a first jaw and a second jaw, and the actuating element comprises a first control cable connected to the first jaw and a second control cable connected to the second jaw, wherein the first control cable and the second control cable are movable in the longitudinal direction relative to the bracket to open and close the pair of jaws. 4. The electrosurgical forceps instrument according to claim 3, characterized in that the actuating element contains a main control cable that passes through the lumen of the flexible rod, while the main control cable branches at its distal end, forming the first control cable and the second control cable. 5. An electrosurgical forceps instrument according to any one of the preceding claims, comprising a holding frame mounted in the proximal part of the lumen, wherein the holding frame has a first attachment area for a coaxial cable and a second attachment area for an actuator, whereby the holding frame is positioned to hold the coaxial cable and the actuating element. element in a fixed orientation relative to each other. 6. An electrosurgical forceps instrument according to any one of the preceding claims, comprising a sleeve formed around a holding frame, a coaxial cable and an actuating element in the lumen of the flexible shaft. 7. An electrosurgical forceps tool according to claim 5 or 6, characterized in that the holding frame has a distal end spaced in the longitudinal direction from the bracket with a stiffener. 8. An electrosurgical forceps instrument according to any one of the preceding claims, characterized in that the flexible dielectric substrate comprises a proximal portion extending between the distal end of the coaxial cable and the proximal end of the inner surface, wherein the proximal portion may deform when opening and closing the pair of jaws. 9. An electrosurgical forceps instrument according to any one of the preceding claims, characterized in that a pair of conductive paths are formed on the flexible dielectric substrate for transmitting microwave energy from the coaxial cable to the first electrode and the second electrode. 10. An electrosurgical forceps instrument according to claim 9, characterized in that the pair of conductive tracks comprises a first conductive track electrically connected to the inner conductor of the coaxial cable and a second conductive track electrically connected to the outer conductor of the coaxial cable. 11. An electrosurgical forceps instrument according to any of the preceding claims, characterized in that the flexible dielectric substrate is a strip of insulating material on which an electrically conductive layer is formed to provide the first electrode and the second electrode. 12. An electrosurgical forceps instrument according to any of the preceding claims, characterized in that a longitudinal slit is formed in the first jaw, and the instrument further comprises: a blade slidably mounted in a longitudinal slot on the first branch; and blade control cable located inside and extending from the lumen for functional engagement with the blade. 13. An electrosurgical forceps instrument according to claim 12, characterized in that the first jaw comprises a cap portion at its distal end, the cap portion being sized to hold the blade in a retracted position. 14. An electrosurgical forceps tool according to claim 13, characterized in that the blade is displaced to the retracted position. 15. Tool electrosurgical forceps according to any one of paragraphs. 12-14, characterized in that the blade control cable is operatively connected to the actuator in such a way that movement of the blade from the retracted position pushes the pair of jaws into the closed position. 16. An electrosurgical forceps instrument according to any one of the preceding claims, characterized in that the pair of jaws are sized to fit within the instrument channel of a surgical examination device. 17. Manual unit for controlling the instrument of electrosurgical forceps according to paragraphs. 1-16 containing: frame; a flexible rod extending from the proximal end of the housing; a coaxial cable passing through the lumen defined by the flexible rod, and the coaxial cable is intended for connection with an electrosurgical instrument located at the distal end of the flexible rod; a control rod extending through the lumen, and the control rod is designed to connect with an electrosurgical instrument located at the distal end of the flexible rod; actuating element mounted with the possibility of sliding on the housing; and rotary device mounted on the body with the possibility of rotation, wherein the coaxial cable and the flexible rod are installed with the possibility of sliding relative to the housing with the help of an actuating element and rotation relative to the housing with the help of a rotary device, and while the control rod has a proximal part, which is installed in a longitudinally fixed position relative to the housing. 18. The hand block according to claim 17, characterized in that the control rod is rotatable relative to the housing. 19. Hand block according to claim 17 or 18, characterized in that the proximal part of the control rod is mounted on a rotary device. 20. Hand block according to any one of paragraphs. 17-19, characterized in that the actuating element contains a rod mounted to slide in the longitudinal direction inside the housing, and the longitudinal direction is aligned with the direction in which the flexible rod extends from the housing. 21. Hand block according to any one of paragraphs. 17-20, comprising a power input port on the final element, and the power input port is connected to transfer the power supplied to it to the coaxial cable. 22. Hand block according to claim 20, characterized in that the direction of connection to the power input port is perpendicular to the direction in which the actuator can slide relative to the housing. 23. A handheld unit as claimed in claim 21 or 22, comprising an RF blocking circuit installed in the actuator between the power input port and the coaxial cable. 24. An electrosurgical device, comprising: an electrosurgical generator for supplying microwave energy; a surgical examination device comprising an instrument cord for insertion into a patient's body, the instrument cord having an instrument channel extending therethrough; hand block according to any one of paragraphs. 17-23 connected to receive microwave energy from an electrosurgical generator, with the flexible shaft of the hand block passing through the instrument channel of the surgical examination device; and an electrosurgical forceps instrument attached to the distal end of the flexible shaft of the hand block, wherein the actuator is connected to control the opening and closing of the electrosurgical forceps instrument, and at the same time, the rotary device is configured to control the rotation of the instrument of the electrosurgical forceps relative to the instrumental channel.

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