DE102016112479A1 - Electrosurgical instrument with thin-film sensor - Google Patents

Abstract

The invention relates to an electrosurgical instrument, in whose proximal end region a handle is arranged and in the distal end region of which a device for generating electrical heat is arranged, characterized in that the distal end region furthermore comprises a thin-film sensor applied by means of thin-film technology.

Description

background

The invention relates to an electrosurgical instrument referred to in the preamble of claim 1 Art.

With electrosurgical instruments tissue can be heated to varying degrees and by the heat z. B. be coagulated. Depending on the length of application and temperature, coagulation leads to denaturation of the proteins, evaporation of fluid from the tissue, and finally tissue burns. The coagulation can z. B. for hemostasis or ablation of tissue.

The heat input into the tissue can be realized by different techniques, for. B. by introducing ultrasonic energy into the area or by heating with high frequency current. The high-frequency current can z. B. in bipolar instruments between jaws arranged electrodes or in monopolar instruments between the instrument and a counter-pole flow through the patient.

When coagulating with high-frequency current, the tissue surrounding the electrode is heated by the current to the extent that the body's own proteins disintegrate, stick together and vaporize intra- and extracellular fluids. This leads to denaturation and shrinkage of the tissue and the blood vessels and thus ultimately to the arrest of bleeding. During ablation, a tissue area that is to be destroyed or removed from the body is denatured in this way. The tissue area treated in this way scartens and is degraded by the body's own processes without having to be surgically removed.

Electrosurgical instruments that use high frequency current can also be used to cut tissue during surgery. During the cutting process, arcs ignite through a vapor layer of cell liquid between the cutting electrode and the tissue. Due to the selective concentration of the high-frequency current in the arc, there is a rapid heating of the cellular tissue, which leads to the sudden evaporation of the cell fluid and ultimately to the cell explosion. Through the distribution of the igniting arcs across the active electrode, anywhere where the vapor layer between tissue and electrode is thin enough, the cutting effect arises. Electrically conductive tissue can be severed almost without mechanical pressure.

In electrosurgery, instruments in the form of forceps are commonly used for welding and severing blood vessels (coagulation forceps). In addition, however, are also einbranchige instruments, such as coagulation scalp, used and those which a heatable loop on their distal, d. H. in the body, have the end.

Usual coagulation forceps are z. In DE 10 2008 028 992 B3 and DE 10 2005 051 367 A1 described. In execution for endoscopic surgery or laparoscopy, the mouth is usually sitting on an elongated shaft and z. B. actuated via an actuating rod arranged at the proximal end of the shaft movable handles. The pliers are z. B. with Hochfrequenzbeaufschlagung used, in particular as bipolar forceps, in which the two jaw parts are connected to different poles of a high frequency source to coagulate captured between the jaws tissue. In scissors design, the jaws are for cutting tissue, and scissors are also used with radio frequency loading, particularly in bipolar fashion, to cut tissue more readily and with immediate coagulation.

When coagulating during an electrosurgical operation, it is important that the two ends of the blood vessels, separated by a cut, be securely sealed by coagulation. For this purpose, the heat input into the tissue must be regulated as accurately as possible. The sealing and cutting times, as well as the energy for sealing or cutting on coagulation forceps are determined in practice by the surgeon based on his observation and experience and / or by a generator-side evaluation of the tissue resistance. An accurate detection of the temperature at the electrodes or the cutting edge of coagulation forceps is not yet. This has the disadvantage that further parameters (for example temperature) for optimizing the cutting or coagulation times have not been available so far, and no statements could be made regarding the temperature development in the lateral area, as a result of which significant thermal damage to the tissue can occur. It can, for. B. come to charring or the surgical instrument can stick to the tissue.

It was therefore considered to carry out a temperature determination directly on the forceps jaw with conventional sensors. Such surgical instruments are for example in the US 5,707,369 described. The therapeutic tissue heating instruments include a temperature measuring device at their distal end. This can be z. B. an RTD resistance thermometer, which exploits the temperature dependence of the electrical resistance of conductors for measuring the temperature. This temperature sensor should be mounted on the outside of the gripper of a surgical gripping instrument.

This type of temperature detection by applying an external sensor on the outside of the forceps jaw has the disadvantage that the measurement does not detect the temperature data in the working area between the pliers. In addition, there is a risk that the sensor is released from the carrier element and that the sensor is mechanically or thermally damaged. An application of the sensors within the working range of the coagulation electrode or cutting blade is not possible without damaging the sensors mechanically and thermally.

The object of the present invention is therefore to provide an electrosurgical instrument which reliably enables the temperature measurement and determination of further relevant parameters in the surgical area during the electrosurgical procedure.

Description of the invention

The object is achieved by an electrosurgical instrument having the features of claim 1. In particular, the object is achieved by an electrosurgical instrument which comprises a thin-film sensor applied by means of thin-film technology to the tissue contact surfaces coming into contact with the tissue to be operated.

Therefore, in a first aspect, the invention relates to an electrosurgical instrument, in the proximal end region of which a handle is arranged and in whose distal end region a device for generating electrical heat is arranged, characterized in that the distal end region furthermore comprises a thin-film sensor applied by means of thin-film technology.

Thin-film sensors applied by thin-film technology are applied to an electrosurgical instrument by deposition of the individual sensor layers. Appropriate methods for applying by thin-film technology are known in the art, described elsewhere herein and include, for. Physical (PVD) and chemical vapor deposition (CVD). Thin-film sensors applied by thin-film technology have a multiplicity of advantages over the conventional, mostly glued or soldered sensors. So are the thin film sensors z. As temperature resistant, while glued sensors can be destroyed or damaged under the conditions of coagulation and can be detached from the instrument. Due to their low mass, the thin-film sensors have a short response time. In addition, they are also much more precise.

The electrosurgical instrument according to the invention is suitable for monitoring the tissue condition, in particular for monitoring and avoiding thermal damage or expected thermal damage.

As distal herein is meant that end or end region of the instrument which will, as a rule, be farthest from the body of the surgeon during an operative procedure with the instrument, i. H. the end or end region that will be in or on the body of the patient. As proximal that end or that end portion of the instrument is referred to, or during the procedure usually closer to the surgeon, z. B. in his hand, is.

The electrosurgical instrument is preferably a resectoscopic or endoscopic instrument. The electrosurgical instrument may, for. B. a cutting instrument, a coagulation instrument and / or an ablation instrument. A cutting instrument in the sense of the invention is an instrument which uses electrical heat generation and thermal action on the tissue for cutting body tissue. The instrument can z. As a knife, a scalpel, tweezers, scissors or pliers. In a preferred embodiment, the instrument is a pair of pliers. The electrosurgical instrument is preferably a Koagulationsinstrument such. B. a coagulation forceps. The electrosurgical instrument is particularly suitable for endoscopic procedures and use in minimally invasive surgery.

In the distal end region of the electrosurgical instrument, a device for generating electrical heat is arranged. According to the invention, the distal end region is the region of the instrument which is in the immediate vicinity of the surgical field. The "Endbereich" can z. B. the last third of the instrument before the end of the instrument, preferably the last fifth, more preferably the last tenth.

The device for electrical heat generation is thus preferably arranged in the last tenth of the electrosurgical instrument in front of its distal end. Preferably, the means for generating electrical heat is disposed in a portion of the electrosurgical instrument which, during surgery, contacts the operated tissue, preferably the device in contact during an operation. "Section" refers to a section in the longitudinal direction of the electrosurgical instrument.

The device for electrical heat generation can, for. Example, be an electrode, preferably an electrode which can be acted upon by high-frequency current. Thus, in one embodiment, the invention relates to an electrosurgical instrument having an electrode for applying high frequency current. In this case, the instrument will be connected to a high frequency generator. The electrode is suitable for electrical heat generation in tissue in combination with a counter electrode. Depending on the type of electrosurgical instrument, the electrode will have different shapes and sizes. Corresponding embodiments are known to those skilled in the art. Advantageously, the or the electrodes are formed flat. In this way, they are particularly well suited for coagulation or for surface tissue removal by the so-called vaporization process. Alternatively, the electrode (s) but also z. B. have the form of a needle electrode, ball electrode, or loop electrode. A loop electrode can, for. B. be used for cutting.

The device for electrical heat generation is preferably mounted on the surface of an insulating layer. As a result, unwanted current flow is avoided. The means for generating electrical heat may occupy all or a majority of the tissue contact surface (s) of the instrument. Alternatively, the device for electrical heat generation is surmounted on all sides by the surfaces of the insulating layer. When applying a device for generating electrical heat to the tissue surface and the surrounding means for generating electrical heat edge of the insulating layer is on the fabric, so that there is a particularly good power shield between the device for electrical heat generation, eg. B. in the form of an electrode, and a counter electrode results. The insulating layer may, for. B. be made of ceramic or plastic. Ceramics are particularly suitable because they are characterized by a high abrasion resistance and excellent insulation properties.

The electrosurgical instrument may, for. B. be a monopolar instrument or a bipolar instrument. A monopolar instrument comprises an electrode at its distal end, the counter electrode of which lies outside the instrument, and z. B. can take a larger area on the back of the patient. The current will then flow from the distal end of the instrument through the patient to the counter electrode. A bipolar instrument comprises two electrodes which, isolated from each other, are applied in the distal region of the instrument. The two electrodes can z. B. be applied to two branches of tweezers or forceps. The current will then flow over a relatively short distance between these two electrodes, e.g. B. on two electrodes which are arranged on the two branches of the jaw part of a coagulation forceps.

The device for electrical heat generation will usually be connected via an electrical line to the proximal end portion of the instrument. This lead may be inside or outside the electrosurgical instrument. Various embodiments are known to those skilled in the art.

The device for generating electrical heat can be functionally connected via connection lines to a control and / or evaluation device. If the device for generating electrical heat is an electrode, then this is z. B. connected via connecting lines functionally connected to a high frequency generator. Corresponding structures are familiar to the person skilled in the art.

The distal end of the electrosurgical instrument further comprises a thin film sensor applied by thin film technique. Thin film sensors are sensors that have a thickness in the micrometre or nanometer range. Preferably, the thin film sensors have a thickness of 10,000 nm or less, 2000 nm or less, preferably 1500 nm or less, more preferably 800 nm or less. In other words, the thickness of the thin film sensors may be from 1 nm to 2000 nm, preferably from 15 nm to 1000 nm, more preferably from 20 nm to 100 nm.

The thin-film technique used to apply the thin film sensor may be e.g. B. selected from the group of physical vapor deposition (PVD) and chemical vapor deposition (CVD). Preferably, the thin film technique is physical vapor deposition. Suitable methods are known to the person skilled in the art. The method for physical vapor deposition is preferably selected from the group consisting of evaporation method, sputter deposition (also: cathode sputtering), ion plating and ionized cluster beam deposition. Thermal evaporation can z. B. electron beam evaporation, laser beam evaporation, arc evaporation or molecular beam epitaxy.

According to the invention, the method of sputter deposition is particularly preferred. In a preferred embodiment, the present invention thus relates to an electrosurgical instrument, in the proximal end region of a handle and in the distal end region of which a device for generating electrical heat is arranged, characterized in that the distal end region furthermore comprises a thin-film sensor applied by means of sputter deposition.

Sputter deposition methods are known to those skilled in the art. In the sputter deposition, atoms are dissolved out of a solid (the cathode), so that the leached atoms can precipitate on the substrate. As a rule, the atoms are released by bombardment with high-energy ions / a plasma. In general, the Sputterdeposition in a vacuum, z. B. in a high vacuum.

The thin-film sensor can be applied by sputter deposition or another thin-film technique directly on the surface of the instrument or on a thin insulating layer. An insulating layer prevents short circuits through the instrument surface when the instrument is made of an electrically conductive material. Thus, the thin-film sensor is preferably applied to an insulating layer, as long as the instrument is made of an electrically conductive material. The insulation layer may, for. B. be a plastic or ceramic layer. Suitable insulation layers are z. For example, alumina layers, silicon dioxide layers and the like.

The insulating layer can also be very thin and z. B. have a thickness of about 10 nm to 5 microns, preferably from about 20 nm to 100 nm.

It should be understood that the insulating layer, as well as the protective layer described elsewhere herein, may be replaced by a similarly strong bonding technology, i. H. through the thin-film technique, z. B. by Sputterdeposition, connected to the instrument and in particular are not glued.

If the surface of the instrument is not metallic or nonconductive, it is not necessary to apply an insulating layer under the thin film sensor. This concerns z. As instruments that are made of a non-conductive material such. As plastic or have already been coated with such.

Any thin film sensors that can be deposited by thin film techniques (i.e., all thin film capable thin film sensors, particularly sputterable thin film sensors) can be used in the present invention. Such suitable thin film sensors are known to the person skilled in the art. The thin-film sensor can, for. B. be selected from the group consisting of thermocouples, strain gauges and piezoelectric elements (piezoelectric elements).

A thin film sensor according to the invention may, for. B. be a strain gauge. Strain gauges that can be applied by thin-film technology, are known in the art. Sputterable strain gauges are the expert z. B. off US 2013/0213129 A1 known. A strain gauge according to the invention comprises or consists of a resistive layer, which changes its electrical resistance during deformations, such as strains or compressions. According to the invention, such strain gauges are preferred, which are adapted to high temperatures between 100 ° C and 200 ° C. As a rule, these resistance layers comprise a resistance meander (also: meander-shaped resistance wire), as well as electrical connections for this resistance meander. About these electrical connections and connecting lines of resistance meander is connected to a system for evaluating the measured changes, for. B. a measuring device.

The strain gauge may be part of a strain gauge configuration, i. a group of a plurality of strain gauges, which are arranged one above the other and / or next to each other and interconnected. Such strain gauge configuration is known to those skilled in the art. The strain gauge can therefore z. B. comprise a plurality of stacked and staggered resistance meander. Such strain gauges are in use and z. B. known as rosette strain gauges or strain gauge rosette.

The resistance meander is made of a material that alters its electrical resistance even at low deformations. Suitable materials are for. B. selected from the group consisting of metals such. Cu-Ni-Mn compounds (eg, Konstantan ^™ , Thyssen Krupp), Ni-Cr compounds and Ni-DLC compounds (nickel-containing diamond-like hydrocarbon layers); or semiconductors, such as. B. silicon semiconductors.

The strain sensitivity of the material of the resistance meander consists, d. H. the proportionality of the resistance change to the elongation of the material is given by the k-factor. Materials having a high elongation sensitivity have a k-factor of k> 2. The resistance meander preferably consists of a material which has a k-factor of k> 2.

The instrument may include strain gauges, e.g. B. to be able to evaluate mechanical stresses on the instrument. In this way, strain gauges z. B. used to determine the pressure applied to the site of intervention. The surgeon or a corresponding computer system can then respond if necessary by appropriate pressure changes or warning signals.

It is also particularly preferred that the thin film sensor is a sensor capable of measuring the temperature, i. H. a temperature sensor. In a preferred embodiment, therefore, the instrument has a thermocouple. Suitable thermocouples are known in the art. A thermocouple has a pair of metallic conductors made of different materials, which are electrically connected at one end and suitable for temperature measurement due to the thermoelectric effect (Seebeck effect). Temperature differences can be determined by the measurable voltage difference between the two metallic conductors.

Thermocouples are classified into different types depending on the operating temperature for which they are suitable. The person skilled in the art is able to determine a thermocouple suitable for the instrument according to the invention on the basis of the position of the thermocouple on the instrument and the temperature to be expected in the region of the thermocouple.

A thin film sensor according to the invention may, for. B. also be a piezoelectric element. Piezoelectric elements are able to generate an electrical voltage under the action of a mechanical force and, therefore, as well as strain gauges, are suitable for providing information about the pressure exerted on the tissue by the instrument. Suitable piezoelectric elements are known to those skilled in the art.

The electrosurgical instrument may also include a plurality of sputter deposition thin film sensors. So the instrument z. B. include various types of thin film sensors that provide different measurement parameters, such. B. a thermocouple and a strain gauge. Alternatively or additionally, the instrument may also comprise thin film sensors applied at various positions, e.g. Thin-film sensors on the tissue contact surfaces and / or on lateral and / or distal surfaces of the distal end region of the instrument, d. H. on surfaces that do not come into contact with the tissue to be operated during the operation.

Thin-film sensors, which are applied in the region of the tissue contact surface of the instrument, are suitable for determining values which can provide immediate information about the condition of the surgically treated tissue. The instrument therefore preferably comprises at least one, preferably two, thin-film sensors on the tissue contact surface of the instrument. It is particularly preferred that the instrument comprises at least one, preferably two thin-film sensors, which is / are applied to the device for generating electrical heat.

Alternatively or additionally, the instrument may comprise at least one, preferably two thin-film sensors, which is / are applied between the device for generating electrical heat and the instrument body. The term "instrument body" in this context refers to the instrument minus the device for electrical heat generation. In these embodiments, the thin film sensor is thus covered by the electric heat generation device. By attaching the thin-film sensor on the instrument side below the means for electrical heat generation, the thin-film sensor can be even better protected from dirt or damage. For this purpose, the thin-film sensor is applied by a thin-film technique prior to the assembly of instrument body and means for electrical heat generation on the back of the device for electrical heat generation or the instrument body, wherein the application by thin-film technology on the back of the device is preferred according to the invention.

In response to the determined values (eg the resistance and / or temperature values), z. B. the current or contact pressure by the surgeon or by an automated control can be modulated. Thin-film sensors, which are mounted laterally or on the side of the distal end region of the instrument facing away from the body tissue to be operated on, are suitable for ascertaining the condition, eg, As the heating, to give from surrounding or adjacent tissue. All of this information helps to prevent or limit thermal damage.

The instrument can z. B. have one, two, three or more thin film sensors. It is preferred that the instrument has at least one thermocouple and at least one strain gauge.

The instrument may further comprise a plurality of thin film sensors deposited one on top of the other. Thus, for example, 1, 2, 3 or more thin film sensors can be applied to one another by a thin-film technique on the instrument. In an advantageous embodiment, 1, 2, 3 or more strain gauges are superimposed on the instrument. The thin-film sensors can overlap only partially or completely. "Overhead" in this context a direction substantially orthogonal to the instrument surface

The thin-film sensor is connected to a device for evaluating the measured data, in particular a measuring device. Similar to the device for electrical heat generation, the thin-film sensor can be z. B. be connected with connecting lines functionally connected to the measuring device. The measuring device is suitable for measuring data, eg. B. temperature or resistance data to determine from the voltage changes in the thin film sensor.

In addition, the measuring device may be functionally connected to the high-frequency generator or a control device in such a way that the means for generating electrical heat is regulated on the basis of the measured data. In other words, the thin film sensor is preferably operatively connected to a regulation instrument capable of modulating the current flowing through the electrical heat generation device, e.g. By changing the generator output. If the measured data indicate too high a temperature, z. B. the power of the device for electrical heat generation are down-regulated and vice versa. This regulation can be automatic. Alternatively or additionally, a warning signal or measured value can be displayed on an output device which makes the operator aware that a limit value has been exceeded.

Those skilled in the general process for and advantageous conditions for the application of thin film sensors by thin-film technology, such. B. Sputterdeposition known. It is thus known that it is advantageous if the instrument surface to which the thin-film sensor and optionally an underlying insulating layer and / or an overlying protective layer described herein is applied has a low surface roughness. A low roughness of the surface ensures reproducible and accurate measurement results.

Preferably, the instrument further comprises a protective layer (also known as passivation layer) which rests on the thin film sensor. Thus, the instrument comprises a layer composite of (a) instrument surface, (b) optional insulation layer, (c) thin-film sensor and (d) optional protective layer. In other words, the protective layer lies on the fabric side of the thin-film sensor. The protective layer preferably completely covers the thin-film sensor, so that no part of the thin-film sensor is exposed to the surgical environment. In this way, the sensor is significantly less sensitive to impact or scratch damage. At the same time, the protective layer does not or only insignificantly limits the measurement performance of the thin-film sensor. Suitable protective layers for thin-film sensors are known in the art and include, for. B. protective layers selected from the group consisting of silicon dioxide layers and aluminum oxide layers and mixtures thereof. Such protective layers do not affect the measurement result of the thin-film sensor at all or only to a negligible extent. Thus, the skilled person as a protective layer for a thermocouple z. B. select no thermally insulating material.

If the instrument comprises one or more thin-film sensors, which are applied between the device for generating electrical heat and the instrument body, an insulating layer is preferably applied between the device for generating electrical heat and the thin-film sensor.

As described elsewhere, the instrument may also include a plurality of thin film sensors stacked on top of each other. In this embodiment, it is advantageous if the individual thin-film sensors are separated from one another by insulating layers. In one embodiment, the instrument thus comprises a layer composite of (a) instrument surface, [(b _n ) insulation layer, (c _n ) thin-film sensor] _n and (d) optionally protective layer. In this layer composite, double layers of insulation layers and thin-film sensors can be repeated over each other several times. "N" stands for the number of these double layers, and thus also for the number of thin-film sensors, which are deposited on top of each other by protective layers.

The instrument has a handle at its proximal end portion. This handle allows the operator to handle the instrument and its operation. Depending on the type of instrument, the handle can be designed differently. So the handle z. B. for actuating the device for generating electrical heat and / or for actuating a jaw part in the distal end region of the instrument. The handle can do this one or more, z. B. two, handle element (s).

The electrosurgical instrument may have at its distal end a jaw part, which is formed with two mouth branches, wherein at least one mouth sector is pivotally mounted. At least one mouth sector preferably has a thin-film sensor on a tissue contact surface. In a preferred embodiment, the instrument is a coagulation forceps. The instrument, e.g. The coagulation forceps are suitable for the generation of electrical heat in the tissue held or to be held by the jaw part.

The electrosurgical instrument may further comprise an elongate shaft. Instruments with such an elongated shaft are particularly for endoscopic surgery, eg. B. in the abdomen, particularly suitable.

Brief description of the figures

In the drawings, embodiments of the invention are shown schematically. Show it:

1 Views of a mouth industry according to the invention on the tissue contact surface (A) and the outside of the mouth sector (B);

2 a side view of an embodiment of a jaw member according to the invention with two unequal mouth sectors, the mouth branches are shown in the open position and detached from each other;

3 a side view of an embodiment of an electrosurgical instrument according to the invention;

4 a schematic representation of an exemplary embodiment of the electrosurgical system according to the invention; and

5 a schematic representation of an alternative embodiment of the electrosurgical system according to the invention.

embodiments

Further advantages, characteristics and features of the present invention will become apparent in the following detailed description of embodiments with reference to the accompanying drawings. However, the invention is not limited to these embodiments.

1 shows two views of a mouth industry according to the invention 18 which is part of a jaw part of a coagulation forceps. Such a jaw part 16 is z. B. in the in 3 shown instrument shown. In 1A is the tissue contact surface 26 the mouth industry 18 that is, the area which is in direct, contiguous contact with the tissue to be coagulated during the planned coagulation. The tissue to be coagulated becomes coagulated between the contact surfaces 26 two mouth branches 18 . 19 held the coagulation forceps.

The tissue contact surface 26 may be in the proximal end of a contact surface continuation 50 include, in the embodiment shown no thin film sensor 36 and no means for generating electrical heat. In the 1A illustrated tissue contact surface 26 further comprises a flat coagulation electrode 48 , which in the example shown in the transverse direction of the mouth industry 18 essentially over the entire area of the tissue contact surface 26 extends. In addition, the mouth industry points 18 on the tissue contact surface 26 Grip grooves in the distal end area 54 to ensure a safer hold of the gripped or gripped tissue.

It is also out 1A to recognize that the tissue contact surface 26 has two thin-film sensors, in particular a distal strain gauge 42 and a more proximal thermocouple 44 , The distal strain gauge can z. B. in the form of a distal strain gauge configuration, z. B. a strain gauge half-bridge for detecting mechanical deformation by bending. The illustrated strain gauge 42 Visibly includes a meander, which undergoes a change in the electrical resistance by mechanical strain and compression. The measured variable can be used for statements on the mechanical pressure on the tissue, eg. To determine if a minimum mechanical pressure has been generated for a vessel seal. The thermocouple 44 Visibly comprises a pair of metallic conductors of different material and is for temperature determination at the tissue contact surface 26 suitable. Both strain gauges 42 as well as thermocouple 44 are from a protective layer 46 coated, ie a protective layer 46 joins the thin-film sensors on the fabric side. In addition, an insulating layer, not shown, can be connected to the thin-film sensors on the instrument side, in particular if the instrument consists of a conductive material.

It is understood that, depending on the instrument type and the requirements of the particular instrument, both the positions of the thin film sensors may differ from those shown, as well as more than the illustrated number of thin film sensors may be applied to the instrument. Shown is only one possible embodiment.

Both the thin-film sensors shown, ie the strain gauges 42 and the thermocouple 44 , as well as the insulation and protective layers 46 are in the illustrated example by Sputterdeposition on the instrument surface, ie the coagulation electrode 48 applied.

In 1B is the outside of the mouth industry 18 represented, ie the side of the mouth industry 18 , the during coagulation is usually not in contact with the tissue to be coagulated, or in 1A represented tissue contact surface 26 on the mouth branch 18 opposite.

The outside 52 the mouth industry 18 includes a thermocouple 44 , by sputtering on an invisible, also sputtered insulation layer on the outside 52 was applied. As mentioned elsewhere, an insulating layer is indicated only on electrically conductive (metallic) materials. So z. B. be dispensed with an insulating layer when the instrument is already electrically isolated at the point in question, z. B. by plastic (injection molding). On the illustrated thermocouple 44 became a protective layer due to sputter deposition 46 applied to the thermocouple. The thermocouple 44 is suitable for providing data and thus information about the temperature development in the vicinity of the operating area and the possibly existing danger of secondary damage. As in 1A are also in 1B the connection lines 64 which the thermocouple 44 with one or more measuring devices 56 connect, not shown.

2 shows a side view of a schematic embodiment of a disassembled jaw member according to the invention with two unequal mouth branches 18 . 19 , where the mouth branches in open position 18 . 19 and are shown detached from each other. The jaw part is arranged, for example, in the distal end region or at the distal end of a coagulation forceps. The mouth branches 18 . 19 are thus suitable for coagulation and each comprise on their tissue contact surfaces 26 Facilities for generating electrical heat 15 that are not shown.

The mouth branches 18 . 19 also each have a joint body 30 with one or more axle bearings 28 on. The joint body 30 serve to connect the two mouth branches 18 . 19 with each other and the connection with z. B. a shaft. The mouth branches 18 . 19 are on their joint bodies 30 over the axle bearings 28 jointed together.

Next to their joint bodies 30 show the mouth branches 18 . 19 each a supporting body 32 on, each serving as a function carrier and, for example, claw-like coagulation force can be pronounced. The supporting body 32 the mouth branches 18 . 19 each further have a contact surface 26 on, at which the Maulbranchen 18 . 19 when in closed position, touch and / or on the mouth branches 18 . 19 touch the tissue to be coagulated.

3 shows a schematic representation of an electrosurgical instrument according to the invention, which advantageously as an electrosurgical jaw instrument 10 , z. B. may be formed as a coagulation forceps. The electrosurgical instrument comprises an elongated, in particular rigid, shaft 12 , one in the proximal end region of the shaft 12 arranged handle 14 for actuating the jaw part and in the distal end region of the shaft 12 arranged jaw part 16 , The shaft 12 can, as shown, in particular be tubular.

In the embodiment shown are two mouth branches 18 . 19 on the jaw part 16 provided, which is designed as Koagulationszangenmaul. Alternatively, only a distal coagulation element or a device for generating electrical heat at the distal end of the instrument can be provided. The illustrated electrosurgical instrument is particularly suitable as coagulation forceps. In the illustrated forceps is an electrosurgical forceps, which is formed in the embodiment for coagulation and cutting purposes. At the movable pliers industry, in addition to this isolated in a manner not shown, two electrodes arranged, which serve for coagulation and / or cutting. With the high-frequency generator switched on, the current flows from one electrode into the body tissue and through its adjacent surface to the second electrode.

For operating the jaw part 16 in the open or closed position is the shaft 12 in 3 with a the shaft 12 longitudinally passing, in the present case designed as a pull or push rod actuator 20 fitted. Especially when using a curved shaft 12 can the actuator 20 be formed as at least partially flexible wire, with the tensile and / or compressive forces of the handle 14 on the jaw part 16 are transferable.

The handle 14 for actuating the jaw part 16 is presently designed as an angled scissor handle, wherein two, in this case equipped with handle rings grip elements 38 . 40 , as Fingeranlagen for the operator and finally to guide and operate the instrument 10 serve. In the embodiment shown by 3 is the first handle element 38 rigid against the shaft 12 arranged and the second handle element 40 movable on the first handle element 38 hinged.

According to the embodiment shown, the actuating element 20 with the movable handle element 40 coupled. The jaw part 16 is by pivoting the second handle member 40 opposite the first handle element 38 into an open or closed position movable. But that will be the shank 12 longitudinally arranged actuator 20 through the movable handle element 40 forcibly guided in the proximal or distal direction relative to the shaft 12 postponed. The opening angle between a first mouth industry 18 and a second mouth industry 19 is thus by means of actuation of the handle 14 adjustable.

In the embodiments shown, the handle 14 for controlling the opening position of the jaw part 16 be operated in the manner of a pair of pliers. In alternative embodiments, the handle is also thought of 14 form as an inline handle, with such a handle 14 usually with the entire hand of the operator is enclosed and the opening position is adjustable by opening and closing the hand. In other alternative embodiments, it is contemplated the longitudinal displacement of the actuator 20 assist or perform with the help of electrical actuators.

In still other embodiments, it is contemplated to form the electrosurgical instrument in a scissor or forceps shape, ie without an elongate shaft 12 ,

The illustrated electrosurgical instrument 8th should tissue, z. B. a blood vessel between two mouth branches 18 . 19 , coagulate by heat. For this purpose, facilities not shown for the sake of drawing simplification provided. Not shown in 3 z. B. the connecting cables 64 which the thin film sensors 36 with one or more measuring devices 56 and the coagulation electrode 48 connect to a high frequency generator.

The following is the use of the electrosurgical instrument according to the invention 8th in an electrosurgical system with respect to the 4 and 5 described.

The electrosurgical system includes a high frequency generator 58 , a measuring device 56 and an electrosurgical instrument 8th These devices are functionally interconnected. The electrosurgical instrument 8th is in 4 as an electrosurgical jaw instrument, z. B. as coagulation forceps formed. In 5 is the electrosurgical instrument 8th as a (single-arm) electrosurgical cutting instrument 68 , z. B. as a coagulation electrode is formed.

The high frequency generator 58 and the measuring device 56 each have several sockets 62 at which a high frequency energy is provided during operation or the voltage measured in the thin film sensor is removed.

High-frequency generator and measuring device can be advantageously installed within a device. In order to facilitate the handling of the surgeon, two or more, preferably all outgoing from the instrument connecting cables can also be combined to form a cable. The cable may then be connected to a slot on the device comprising high frequency generator and measuring device.

The electrosurgical system further includes hardware and software that can regulate energy delivery and evaluate the measurements taken by the thin-film sensor (s).

The high frequency generator 58 may have multiple modes of operation, eg, a clipping mode and a coagulation mode. The measuring device 56 is with the high frequency generator 58 preferably signal technology by a connection 60 connected. The connection 60 may comprise an evaluation system, eg in the form of a computer system, which regulates the high-frequency generator based on the measured values, for example, or issues warning signals when exceeding or falling below defined threshold measured values.

The electrosurgical instrument 8th each includes a handle 14 and a device for generating electrical heat. The device for electrical heat generation 15 is in 4 as two coagulation electrodes 48 on the mouth branches 18 . 19 trained and in 5 as a cutting electrode 66 , On the surface of the coagulation electrode 48 on mouth industry 19 ( 4 ) or on the surface of the cutting electrode 66 ( 5 ) is a thin-film sensor by thin-film technology 36 applied. The thin film sensor 36 may be in the embodiments shown, for example, a thermocouple or a strain gauge. It is understood that the electrosurgical instruments shown 8th may also include multiple thin film sensors.

In further exemplary embodiments, the instrument comprises z. B. several thin film sensors, such as. B. on both mouth sectors of a jaw part in each case two thin-film sensors, wherein a thin-film sensor is applied in each case directly on the means for generating electrical heat and a thin-film sensor is mounted respectively on the outside of Maulbranchen. As a result, thermal measurements (by thermocouples) and measured values for the mechanical pressure (by strain gauges) can be determined spatially differentiated so that the surgeon has an accurate picture of the surgical site can make. As a result, lateral damage can be even better avoided.

In addition, as mentioned elsewhere, the instrument may also comprise a configuration of 2, 3 or more strain gauges in which a plurality of strain gages e.g. B. can be arranged one above the other and / or next to each other. The strain gauges can be used in bridge circuits, such. B. quarter, half or full bridges, taking into account the spatial location.

Like the coagulation electrodes 48 ( 4 ) or the cutting electrode 66 ( 5 ) are also the thin film sensors 36 in not exactly illustrated manner with the connecting cables 64 connected. The thin-film sensors 36 are in particular by means of connecting cables 64 over at a measuring device 56 attached sockets 62 with this measuring device 56 functionally connected.

Although the present invention has been described in detail with reference to the embodiments, it will be understood by those skilled in the art that the invention is not limited to these embodiments, but rather modifications are possible in such a way that individual features omitted or other combinations of individual features presented realized unless the scope of the appended claims is exceeded. The present disclosure includes all combinations of the featured individual features.

LIST OF REFERENCE NUMBERS

8th

 electrosurgical instrument

10

 electrosurgical jaw instrument

12

 shaft

14

 handle

15

 Device for generating electrical heat

16

 jaw

18

 first mouth industry

19

 second mouth industry

20

 jig

24

 joint

26

 Contact surface of the mouth sector

28

 Achslager

30

 joint body

32

 Supporting body of the mouth industry

36

 thin film sensor

38

 first handle element

40

 second handle element

42

 Strain gauges

44

 thermocouple

46

 protective layer

48

 coagulation

50

 Contact area Continued

52

 Outside mouth sector

54

 grip grooves

56

 measuring device

58

 High-frequency generator

60

 connection

62

 Rifle

64

 connecting cable

66

 cutting electrode

68

 electro surgeon. cutting instrument

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102008028992 B3 [0007]
• DE 102005051367 A1 [0007]
• US 5707369 [0009]
• US 2013/0213129 A1 [0034]

Claims (11)

Electrosurgical instrument ( 8th ), in the proximal end portion of a handle ( 14 ) is arranged and in the distal end region of a device for electrical heat generation ( 15 ), characterized in that the distal end region further comprises a thin-film sensor ( 36 ). Electrosurgical instrument ( 8th ) according to claim 1, characterized in that the thin-film sensor ( 36 ) by physical vapor deposition on the electrosurgical instrument ( 8th ) is applied. Electrosurgical instrument ( 8th ) according to one of the preceding claims, characterized in that the thin-film sensor ( 36 ) by sputter deposition on the electrosurgical instrument ( 8th ) is applied. Electrosurgical instrument ( 8th ) according to one of the preceding claims, characterized in that the thin-film sensor ( 36 ) is selected from the group consisting of thermocouples ( 44 ), Strain gauges ( 42 ) and piezo elements. Electrosurgical instrument ( 8th ) according to one of the preceding claims, characterized in that the distal end region comprises a plurality of thin-film sensors ( 36 ). Electrosurgical instrument ( 8th ) according to one of the preceding claims, characterized in that a thin-film sensor ( 36 ) on a tissue contact surface of the instrument ( 8th ) is applied. Electrosurgical instrument ( 8th ) according to one of the preceding claims, characterized in that at least one thin-film sensor ( 36 ) on the electrical heat generation facility ( 15 ) is applied and / or between the device for electrical heat generation ( 15 ) and the instrument body is applied. Electrosurgical instrument ( 8th ) according to one of the preceding claims, characterized in that the instrument ( 8th ) at its distal end a jaw part ( 16 ) with two mouth branches ( 18 . 19 ), wherein at least one mouth sector is pivotally mounted. Electrosurgical instrument ( 8th ) according to one of the preceding claims, characterized in that the instrument ( 8th ) an elongated shaft ( 12 ) having. Electrosurgical instrument ( 8th ) according to one of the preceding claims, characterized in that the instrument ( 8th ) is a coagulation forceps. Electrosurgical instrument ( 8th ) According to one of the preceding claims, characterized in that the device for electrical heat production is a high-frequency electrode can be acted upon in tissue.

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