WO2022023401A1 - Part of a surgical instrument - Google Patents

Abstract

The invention relates to a part (10) of a surgical instrument, having at least one sensor (20a-c) which is at least partly integrated into the part (10).

Description

description

title

Part of a surgical instrument

The present invention relates to a part of a surgical instrument, in particular a coagulation and/or thermofusion tool.

State of the art

Bleeding is unacceptable in minimally invasive surgery because the surgical site is not accessible with a swab, for example. Therefore, electrosurgery is used in this area in particular, in which the tissue is sclerosed or first coagulated and/or thermofused before the cut. The tissue is thermally heated by a high-frequency current flow and the proteins coagulate and tissue fluid or water is expelled from the affected tissue section. This enables a reliable closure of the blood vessels before the surgical incision.

Coagulation takes place in a temperature range of 60° to 80° C and thermofusion in a temperature range of 90° to 100° C. If the temperature reached is below this, there is a risk of unwanted bleeding. At even higher temperatures, the coagulated or thermofused tissue is damaged to such an extent that solid scars form or the tissue burns, which has a negative effect on the healing process. However, it is not possible to measure the temperature directly on the coagulated tissue; instead, the temperature reached is only indirectly estimated by measuring the impedance of the high-frequency generator. Disclosure of Invention

The part of a surgical instrument has at least one sensor that is at least partially embedded in the part. The surgical instrument is in particular a coagulation and/or thermofusion tool. A coagulation and/or thermofusion tool is understood to mean a tool that is set up for the coagulation and/or thermofusion of tissue. In this case, the part of the coagulation and/or thermofusion tool is in particular a jaw of a coagulation and/or thermofusion tool designed, for example, in the form of pliers, which has at least one coagulation and/or thermofusion electrode.

The sensor is, in particular, a temperature sensor which, for example, can be unstructured or structured in an elongate and/or meandering shape. The structuring of temperature meanders, for example via the process of laser trimming, generates high-precision and controllable measuring resistors that are required for measurement technology. The resistance of each temperature sensor is preferably in the range of 10 to 1000 ohms and more preferably in the range of 95 to 205 ohms. Preferred materials for temperature meanders are platinum, platinum alloys, in particular platinum-palladium alloys, platinum cermet, silver, silver alloys, gold or gold alloys. Application can be carried out by a contacting or non-contacting coating method, in particular by means of screen printing or also by means of a jet method over a large area or already structured. This can then be followed by a laser trimming process to set the desired resistance. This enables the coagulation and thermofunction temperature to be recorded in situ for precise control during an operation. If several temperature sensors are provided, a sequential and spatially resolved temperature measurement can be carried out. In addition, very small tissue areas can be measured and treated surgically.

Furthermore, the sensor can be designed as a temperature sensor, in particular by being designed as a thermocouple. The The thermocouple is preferably designed as a pair of conductor tracks with an overlap.

The overlap can preferably be a conductor track crossing or two contact pads lying one on top of the other or also two free forms lying one on top of the other. The conductor tracks are routed in the same material, for example via a flex foil or cable strand, from an electrical voltage measuring device to a reference measuring point. In one embodiment of the thermocouple, one track is made of silver and the other track is made of nickel. In another embodiment of the thermocouple, one conductor track consists of nickel and the other conductor track consists of a nickel-chromium alloy. In another embodiment of the thermocouple, one trace is gold and the other trace is PEDOT:PSS (poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) polymer blend) or polyaniline.

A transition from the conductor tracks of the thermocouple to a flex film can be carried out in particular by mechanical pressing or by conductive gluing. The contact point should be as thin as possible so that there is no temperature difference between a ceramic body acting as a component carrier and the flex film in the contact area. This could cause measurement errors due to thermal stresses between the trace and the conductive adhesive.

Thermocouples can be applied using the same non-contact coating methods that are preferred for temperature meanders. In principle, however, the thermocouples can also be applied using contact-based coating methods, such as screen printing, for example.

Compared to temperature meanders, thermocouples have the advantage that the resistance of the measuring traces only slightly falsifies the measurement result compared to resistance-based temperature meanders. In addition, thermocouples have a smaller area requirement than resistance-based temperature sensors, which means that the number of sensors can be increased or the application can be carried out in a smaller part. The part preferably has a ceramic body, in particular a body made of aluminum oxide (AI2O3), zirconium oxide (ZrCh), magnesium-doped zirconium oxide, YSZ (yttria stabilized zirconia: zirconium oxide partially stabilized with yttrium oxide (Y2O3), ATZ (alumina toughened zirconia), made of spinel (magnesium aluminate; MgA O^, of forsterite (magnesium silicate (Mg2SiC>4) or of cordierite (Mg2Al3[AISi50ie]). The ceramic body is electrically insulating and therefore well suited for the application and embedding of sensors. Temperature meanders can appear be sintered or hardened onto the ceramic body, in particular thermally/optically.

In one embodiment of the part of the surgical instrument, it is preferred that the ceramic body is a monolithic or differently graded three-dimensional body. This can have integrated functional chambers and/or membranes. For this purpose, the ceramic body can be produced, for example, as a compact. However, production using CIM (Ceramic Injecting Molding) technology is preferred. This has the advantage that a filigree but complex three-dimensional CIM design can be freely combined with very fine meandering temperature sensors on the surface. Another advantage of an injection molded ceramic body is that there are no symmetry requirements. The shape can be adapted to the functional requirements. This allows, for example, the sensing area to be flattened in order to use inexpensive printing techniques for the sensors.

For this purpose, preferably spray materials containing ZrO 2 and/or Al 2 O 3 are used, particularly preferably graded ceramic spray materials such as in particular Al 2 O 3 -ZrO 2 mixtures. The spray material preferably has an average particle size dso in the range from 0.1 μm to 0.3 μm, which can be determined using the ISO 13320 standard, and solids contents of up to 70% by volume. This allows a body that can be easily structured by means of crack-free sintering or co-sintering at a temperature in the range from 1,150° C. to 1,550° C. with metallic functional layers. In another embodiment of the part of the surgical instrument, it is preferred that the ceramic body is a composite body that has a plurality of ceramic foils and in which at least one sensor is at least partially embedded. In order to facilitate embedding, it is preferred that the ceramic body has at least three ceramic foils. The thickness of each ceramic foil is in particular in the range from 50 μm to 800 μm.

A thickness in the range from 50 μm to 150 μm is preferred for the upper film in order to be able to quickly measure temperature changes by means of temperature sensors arranged underneath. Furthermore, it is preferred that at least two ceramic foils consist of different materials. In addition, it is preferable that an upper sheet is selected to have a higher specific thermal conductivity than a lower sheet of the ceramic body. In particular, the specific conductivity of the upper film is higher than the specific conductivity of the lower film at a temperature of at most 300°C. The upper film is understood to be the film that is in contact with a coagulation and/or thermofusion electrode of the part and is therefore located on the tissue side of the surgical instrument, and the lower film is understood to be the film that faces away from the tissue side . The lower foil preferably has a greater thickness than the upper foil and in this way can impart stability to the ceramic body, while the upper foil for embedding the at least one sensor is selected to be thinner.

Ceramic foils are preferred which, as so-called green ceramic foils, can be coated, functionalized and structured by a coating process such as screen printing or the jet process.

For example, the plurality of ceramic foils may be sintered together at a temperature in the range of 1200°C to 1700°C to form the ceramic body. Alternatively, they can also be manufactured and bonded using LTCC technology (Low Temperature Cofire Ceramic) at a temperature in the range of 800°C to 1,100°C. In order to be able to apply a coagulation and/or thermofusion electrode to the ceramic body, it is preferable for the latter to have a width in the range from 0.5 mm to 20.0 mm. Furthermore, it is preferred that it has a recess with a depth in the range from 0.05 mm to 2.00 mm, into which the electrode can be inserted if it is designed as a metallic component. Alternatively, the electrode can be printed onto the ceramic body, for example by means of screen printing.

In order to embed and electrically insulate the sensor, it is preferred that at least one sensor is arranged between two foils in the ceramic body. In this case, an arrangement between the upper foil and the foil lying directly underneath is preferred in order to enable a measurement as close as possible to the tissue side of the surgical instrument. Arranged between the foils means that the sensor contacts both foils. It can be fully or partially embedded or buried in one of the films, or also partially embedded in both films.

In order to enable a temperature measurement close to a coagulation and/or thermofusion electrode, it is preferred that at least one sensor is arranged below the coagulation and/or thermofusion electrode arranged on the ceramic body. On the other hand, if the temperature is to be measured away from the coagulation and/or thermofusion electrode, it is preferable for at least one sensor to be arranged horizontally offset to the coagulation and/or thermofusion electrode, which is arranged on the ceramic body. Horizontal is understood to mean along a plane in which a ceramic foil is arranged. In order to enable a temperature measurement that is as close to the surface as possible, it is preferred that at least one sensor is arranged next to a coagulation and/or thermofusion electrode, which is arranged on the ceramic body. The sensor is at least partially embedded in a covering layer in order to prevent the sensor from being short-circuited by tissue fluid. This covering layer can consist, for example, of aluminum oxide, of YSZ, of silicon or of an electrically insulating polymer such as a parylene.

In order to enable a connection of the at least one sensor with electronic components that are on the tissue side of the are arranged on the side facing away from the surgical instrument and are protected there from the coagulation and/or thermofusion heat, the at least one sensor preferably has at least one contact which runs along at least one side of the ceramic body. The is preferably connected to this contact via a conductor track with a width in the range from 0.05 mm to 2.00 mm, particularly preferably in the range from 0.10 mm to 1.00 mm. The contact can run along an edge chamfer or side chamfer of the ceramic body, which is rounded and tangential and preferably has a radius in the range from 50 μm to 250 μm. Contact can then be made via a metal conductor track along this phase. In this case, the thickness of the conductor track is preferably in the range from 1 μm to 30 μm. In order to enable simple and secure further contacting on cables, stranded wires or flex foils, each contact preferably ends in a contact area on the side of the part facing away from the fabric side, the area of which is preferably in the range from 0.025 to 2.500 mm ² . It is particularly preferably in the range from 0.05 to 1.00 mm ² . The cross section of the aforementioned conductor track of the contact is preferably at least 2.5 times as large as the cross section of the conductor track of the temperature meander in order to be able to carry out the contact with low resistance compared to the temperature meanders.

In another embodiment, at least one sensor has at least one via through the ceramic body. In this way, external contacts that would have to be passivated by means of an insulating layer can be dispensed with. A particularly simple embodiment of such a via consists of a through-hole with a circular cross-section, which has a diameter in the range of preferably 0.05 to 2.00 mm, particularly preferably 0.07 to 1.00 mm. The edge exit is preferably provided with a bevel, particularly preferably roundish-tangential. The radius is preferably in the range between 50 μm and 250 μm. The through-connection can then take place in particular by means of a metallic inner wall layer with a thickness in the range from 1 μm to 30 μm. This metallization takes place via the exit forms or exit edges to the surfaces of the ceramic body. They bind on the one hand electrically to the sensor and on the other hand they can connect to a contact pad, which is preferably dimensioned in the same way as the contact pad that is also used when making contact on one side of the ceramic body. However, it is also possible to completely fill the through-hole with a metal paste by means of a Viafill contact. Such vias can be produced particularly advantageously using CIM technology. Small hole structures and very thin inner wall thicknesses can be realized by ceramic injection molding, so that the sensing area can be made thin. The precise and simple connection of sensors on the top of the ceramic body to contact pads on the underside is a major advantage of CIM technology. Due to the complex three-dimensional component shaping of the external and volume geometry, through holes and thin open spaces, the part of the surgical instrument can be manufactured quickly, easily and inexpensively in combination with the sensor.

The same materials are preferred both for the contacts along one side of the ceramic body and for the vias, which are also preferred for the temperature meanders. In particular, however, they have a lower resistance in order to represent better resistance ratios. A temperature meander and its contacts or vias are particularly preferably made of the same material. This makes it possible to produce a temperature sensor together with its contacts, for example, in the same printing process.

Not only the fabric side itself is suitable for the arrangement of sensors. If a coagulation and/or thermofusion electrode is arranged on an upper surface of the ceramic body, provision can be made for arranging at least one sensor on a lateral surface of the ceramic body. This can be both an outer surface and a side surface at a recess in the ceramic body.

If a temperature measurement is to take place as close as possible to the coagulation and/or thermofusion electrode, it is also possible to embed at least one sensor at least partially in a cover layer and to arrange it on the coagulation and/or thermofusion electrode. Furthermore, it is also possible to embed at least one sensor completely in a ceramic intermediate layer and to arrange it between the coagulation and/or thermofusion electrode and the ceramic carrier. This ceramic intermediate layer can consist of the same materials as the ceramic carrier. Its thickness is preferably in the range from 1 μm to 20 μm.

Brief description of the drawings

Embodiments of the invention are shown in the drawings and are explained in more detail in the following description.

1 shows a plan view of part of a surgical instrument according to an embodiment of the invention.

FIG. 2 shows a transparent representation of a section of a part of a surgical instrument according to another exemplary embodiment of the invention.

FIG. 3 shows a top view of a part of a surgical instrument according to yet another embodiment of the invention.

FIG. 4 shows a top view of a part of a surgical instrument according to yet another embodiment of the invention.

FIG. 5 shows a sectional view of a detail of a part of a surgical instrument according to yet another embodiment of the invention.

6 shows an isometric view of a portion of a surgical instrument according to yet another embodiment of the invention.

FIG. 7 shows a schematic sectional illustration of a partial area of a part of a surgical instrument according to yet another exemplary embodiment of the invention. FIG. 8 shows a schematic sectional illustration of a partial area of a part of a surgical instrument according to yet another exemplary embodiment of the invention.

FIG. 9 shows a schematic representation of a partial area of a part of a surgical instrument according to yet another exemplary embodiment of the invention, the sensors of which are designed as thermocouples.

Embodiments of the invention

Several exemplary embodiments of a part of a surgical coagulation and/or thermofusion instrument for microsurgery are described below. This part is a jaw or jaw part of the coagulation and/or thermofusion instrument, which is designed as coagulation and/or thermofusion forceps. This part has sensors that are designed as temperature meanders (Pt100 Ohm or Pt200 Ohm).

The part 10 shown in Fig. 1 has a ceramic body 11, for example 10 mm wide, in which a coagulation and/or thermofusion electrode 12 is inserted into a recess such that its upper side faces the surface of the ceramic body 11 is sublime. The coagulation and/or thermofusion electrode 12 is curved and a further recess 13 is provided in the ceramic body 11 between its two arms. In each case between the coagulation and/or thermofusion electrode 12 and the edge of the part 10, three temperature sensors 20a-20c are arranged. Each of the temperature sensors 20a-20c is connected to contact pads on the underside of the part 10 by means of two vias 21a-21c, 22a-22c.

Fig. 2 shows an example of a further sensor 20d how this through-plating can take place. The ceramic body 11 consists of four ceramic foils 111 to 114 which are sintered together. The first sheet 111 is at the top of part 10. The fourth sheet 114 is located at its bottom. The sensor 20d is arranged between the first foil 111 and the second foil 112 and is thus electrically insulated. In order to ensure good heat transfer to the environment, the first film 111 has a cutout 14 in the vicinity of the sensor 20d, through which the second film 112 is exposed there. The sensor 20d has conductive traces terminating at through-holes of circular cross-section passing through the second to fourth ceramic foils 112 to 114 and each having a radius of, for example, 0.5 mm. They each have, for example, 15 μm thick inner wall layers, by means of which they form the vias 21d, 22d. Those terminate at contact pads 31, 32 on the underside of part 10 to which cables can be attached. The contact pads each have an area of, for example, 0.5 mm ² .

FIG. 3 shows an exemplary embodiment of a part 10 which, like the exemplary embodiment according to FIG. 1, has three sensors 20e to 20g. However, the contacts 21e to 21g, 22e to 22g of these sensors 20e to 20g are each guided on one side of the part from the top to the bottom.

FIG. 4 shows how a plurality of sensors 20h to 20k can share conductor tracks in an exemplary embodiment for the purpose of contacting. While each of the first contacts 21h to 21j of the first three sensors 20h to 20j is routed to one side of part 10 via its own conductor track, the second contacts 22h to 22j are each brought together to form a conductor track. In the case of the following three sensors 20n to 20k, the first contacts 21n to 21k are brought together to form a conductor track, while the second contacts 22n to 22k are each led individually to one side of the part.

Using the example of a sensor 20n, FIG. 5 shows how contacts 21n, 22n can each be routed on an outside of the ceramic body 11 from the top to the bottom of the part in an exemplary embodiment of the invention. They are designed here as, for example, 0.5 mm wide and 15 μm thick metallization of the side edges of the ceramic body 11 and form surfaces on the underside of the part which have the function of Contact pads 31, 32 in Fig. 2 can meet. The metallizations follow a rounding bevel, which has a radius of 100 μm, for example.

In an exemplary embodiment of the invention, FIG. 6 shows various positions of the ceramic body 11 at which sensors can be arranged. In contrast to the exemplary embodiments according to FIGS. 1, 3 and 4, in this exemplary embodiment the coagulation and/or thermofusion electrode 12 occupies the entire upper side of the ceramic body 11, insofar as this is not interrupted by the recess 13. In this exemplary embodiment, too, sensors can be arranged on the upper side of part 10 and thus on the coagulation and/or thermofusion electrode 12 . This is shown as an example for a sensor 20o with its two contacts 21o, 22o, which are designed as through contacts. However, sensors can also be arranged on the side surfaces of the ceramic body 11 . This is shown as an example for a sensor 20p with its contacts 21p, 22p, which are designed as through-contacts. Finally, sensors can also be arranged on the side surfaces of the ceramic body 11, which result in the side surfaces of the recess 13. This is shown as an example for a sensor 20q and its contacts 21q, 22q, which are designed as through contacts.

FIG. 7 shows various possible positions of sensors on and in a composite body from which ceramic body 11 is made. A sensor 20r is arranged directly on the coagulation and/or thermofusion electrode 12 and embedded in a covering layer 41. This type of embedding can also be used for the sensors 20o, which are arranged on the upper side of the coagulation and/or thermofusion electrode 12 according to FIG. A sensor 20s is arranged between the first ceramic layer 111 and the second ceramic layer 112 below the electrode 12 and another sensor 20t is arranged between the second layer 112 and the third layer 113 below the electrode 12 . A sensor 20u is arranged on the first layer 111 and thus on the ceramic body 11 next to the electrode 12 and is surrounded by a covering layer 42 . A further sensor 20v is arranged below this sensor 20u between the first layer 111 and the second layer 112, which is thus offset horizontally to the coagulation and/or thermofusion electrode 12 is arranged. All sensors 20s, 20t, 20v arranged between layers are in each case partially embedded in the layer above them and partially in the layer below them. The connection of a sensor with contact pads 31, 32 on the underside of the ceramic body 11 is shown as an example for the sensor 20t by means of vias. However, all other sensors shown in FIG. 7 can be connected to the contact pads 31, 32 in the same way by means of plated-through holes.

FIG. 8 shows how a sensor 20w can be placed underneath the coagulation and/or thermofusion electrode 12 without embedding it between layers of the ceramic body 11. FIG. The sensor 20w is arranged on the ceramic body 11 and is surrounded there by a ceramic intermediate layer 43 . The coagulation and/or thermofusion electrode 12 is arranged on this intermediate layer 43 .

While the first ceramic layer 111 in the exemplary embodiments described above consists, for example, of aluminum oxide and the further ceramic layers 112-114 consist, for example, of YSZ, the cover layers 41 to 43 consist, for example, of the parylene poly-p-xylylene. The thickness of the first ceramic layer is 100 μm, for example, the thicknesses of the second ceramic layer 112 and the third ceramic layer 113 are each 200 μm, for example, and the thickness of the fourth ceramic layer is 400 μm, for example. The thickness of the ceramic intermediate layer 43 is 10 μm, for example.

In a further exemplary embodiment, the ceramic body 11 is not manufactured as a composite body. Instead, it is produced using CIM technology from a graded A Os-ZrC^ spray material, which has an average particle size d50 of 0.20 pm. For this purpose, a green compact is injected and subjected to sintering at a temperature of, for example, 1,450° C. in order to obtain a graded, three-dimensional ceramic body 11 .

Further exemplary embodiments of the invention provide for the sensors to be in the form of thermocouples. Fig. 9 shows three sensors 20x, 20y, 20z, the are arranged on a part 10 of a surgical coagulation and/or thermofusion instrument. These each have an upper metal surface 23x, 23y, 23z, which consists of silver, for example, and a lower metal surface 24x, 24y, 24z, which consists of nickel, for example. The metal surfaces 23x, 23y, 23z, 24x, 24y, 24z are each designed as contact pads. The lower metal surfaces 24x, 24y, 24z overlap the upper metal surfaces 23x, 23y, 23z. Each lower metal surface 24x, 24y, 24z is connected to an electrical voltage measuring device 50, which is arranged in a control unit arranged outside of the surgical coagulation and/or thermofusion instrument, by means of an electrical line 25x, 25y, 25z assigned to it. The upper metal surfaces 23x, 23y, 23z are connected to the voltmeter 50 by means of a common electric line 25. Also in each of the exemplary embodiments of part 10 according to the invention, which are shown in FIGS.

Claims

Expectations 1. Part (10) of a surgical instrument, having at least one sensor (20a-z) embedded at least partially in the part (10). 2. Part (10) according to claim 1, characterized in that the surgical instrument is a coagulation and/or thermofusion tool. 3. Part (10) according to claim 1 or 2, characterized in that the sensor (20a-z) is a temperature sensor. 4. Part (10) according to claim 3, characterized in that the sensor (20a-z) is a thermocouple. 5. Part (10) according to claim 4, characterized in that the thermocouple is designed as a pair of conductor tracks. 6. Part (10) according to any one of claims 1 to 4, characterized in that it has a ceramic body (11). 7. Part (10) according to claim 6, characterized in that the ceramic body (11) is a monolithic or differently graded three-dimensional body. 8. Part (10) according to claim 7, characterized in that the ceramic body (11) was produced by means of CIM technology. 9. Part (10) according to claim 6, characterized in that the ceramic body (11) is a composite body which has a plurality of ceramic foils (111, 112, 113, 114) and in which at least one sensor (20a-z) is at least partially embedded. 10. Part (10) according to claim 9, characterized in that at least one sensor (20d, 20s, 20v) is arranged between two foils (111, 112, 113, 114) in the ceramic body (11). 11. Part (10) according to claim 9 or 10, characterized in that at least one sensor (20s, 20t) is arranged below a coagulation and/or thermofusion electrode (13) which is arranged on the ceramic body (11). 12. Part (10) according to claim 9 or 10, characterized in that at least one sensor (20a-g, 20u, 20v) is arranged offset horizontally to a coagulation and/or thermofusion electrode (13) which is mounted on the ceramic body ( 11) is arranged. 13. Part (10) according to any one of claims 6 to 12, characterized in that at least one sensor (20u) is arranged next to a coagulation and/or thermofusion electrode (13) arranged on the ceramic body (11), wherein it is at least partially embedded in a covering layer (42). 14. Part (10) according to any one of claims 6 to 13, characterized in that at least one sensor (20a-d, 20t) has at least one via (21a-d, 21o-q, 21t, 22a-d, 22o-q, 22t) through the ceramic body (11). 15. Part (10) according to one of Claims 6 to 14, characterized in that at least one sensor (20e-n) has at least one contact (21e-n, 22e-n) which is located on at least one side of the ceramic body (11 ) runs along. 16. Part (10) according to any one of claims 6 to 15, characterized in that a coagulation and / or thermofusion electrode (13) is arranged on an upper surface of the ceramic body (11) and at least one Sensor (20p, 20q) is arranged on a lateral surface of the ceramic body (11). 17. Part (10) according to any one of claims 6 to 16, characterized in that at least one sensor (20w), which is embedded in a ceramic intermediate layer (43), between a coagulation and / or thermofusion electrode (13) and the ceramic Carrier (11) is arranged. 18. Part (10) according to one of claims 1 to 17, characterized in that at least one sensor (20r), which is at least partially embedded in a covering layer (41), on a coagulation and/or thermofusion electrode (13) of the part (10) is arranged.