Sensor system

Abstract

The invention relates to a sensor system (10), in particular for monitoring the healing process after anastomosis, in particular intestinal anastomosis. Said sensor system (10) comprises a flat carrier (30) made of a resorbable and preferably porous material, on which sensor elements (40, 42, 44) are arranged. On both sides (30A, 30B) of the carrier (30), a contact surface (32A, 32B) is provided for the two-sided placement of interconnected tissue sections, the healing together of which is monitored as intended by means of the sensor system (10), and bioresorbable or biocompatible conductor tracks (50) are provided on at least one side (30A, 30B) of the carrier (30), which conductor tracks are electrically connected to the sensor elements (44) or directly form the sensor elements (40, 42).

Description

[0001] 0100P0002WQ Page 1 3 December 2025

[0002] Sensor system

[0003] SCOPE OF APPLICATION AND STATE OF THE ART

[0004] The invention relates to a sensor system, in particular for monitoring the healing process after an intestinal anastomosis operation.

[0005] An anastomosis operation is a surgical procedure in which two separate sections of tissue, usually in the digestive tract, are joined together. This typically occurs after a resection, in which part of the intestine is removed. The anastomosis restores the patency of the intestine and allows for normal digestion. The procedure is frequently performed on patients with colorectal cancer, inflammatory bowel diseases, or injuries to the intestine.

[0006] Risks exist after anastomosis surgery, including suture and / or staple failure, where the connection becomes leaky. This can allow intestinal contents to enter the abdominal cavity, leading to serious infections. Other risks include abscesses, bowel obstructions, and inflammatory reactions, which can delay the healing process. Infections, bleeding, and postoperative complications such as impaired wound healing are also possible.

[0007] Careful postoperative monitoring is therefore crucial in order to detect and treat complications early.

[0008] TASK AND SOLUTION

[0009] The object of the invention is to provide a sensor system that detects postoperative difficulties in order to initiate appropriate medical measures in a timely manner.

[0010] For this purpose, a bioresorbable sensor system is proposed, specifically designed to monitor the healing process after an anastomosis. The sensor system comprises a sensor unit that is implanted into the patient's body during surgery.

[0011] This sensor unit has a flat carrier made of resorbable and preferably porous material, on which sensor elements are arranged. The carrier can, in particular, consist of a resorbable polymer. At least one sensor element is located on each side of the carrier. 0100P0002WQ Page 2

[0012] The substrate is designed for the bilateral placement of interconnected tissue sections, the healing of which is monitored using the sensor system. Bioresorbable or biocompatible conductive traces are attached to at least one side of the substrate; these are either electrically connected to the sensor elements or form the sensor elements themselves.

[0013] The fundamental principle of the proposed sensor system is that the healing process can be monitored particularly well when sensor data is acquired directly at the junction of the tissue segments. This is especially true in the case of a bowel anastomosis, where the two ends of the intestine are joined by staples and / or sutures. The bioresorbability of the support allows the tissue to grow together through the support. This is further promoted if the support is made of porous material. Connecting elements such as a suture or staple preferably penetrate the degrading and preferably porous support.

[0014] Various materials are suitable for the carrier.

[0015] In particular, polydioxanone (PDO, PDS, PPDO, PPDX, Resomer X206S) is considered a suitable material. Polydioxanone is a synthetic, bioresorbable polymer characterized by its good biocompatibility and slow degradation rate. Because PDO degrades slowly in tissue, it provides structural support for an extended period before being resorbed. Polydioxanone is available, for example, under the trade names PDS and PDS Brain.

[0016] Polyglactin (PLGA), in particular polyglactin 910, is a copolymer material of lactic acid and glycolic acid that is bioresorbable and biocompatible. It offers a good compromise between strength and degradation rate.

[0017] Polyglycolic acid (PGA) is another resorbable polymer known for its high strength and rapid degradation rate. It is particularly suitable when rapid degradation of the support is desired. Polyglycolic acid is commercially available, for example, under the trade name Dexon.

[0018] Poliglecaprone 25 is a copolymer of glycolide and E-caprolactone, known for its flexibility and biocompatibility. This material is also particularly suitable when rapid degradation is desired.

[0019] Polyglycolic acid-caprolactone is a bioresorbable copolymer consisting of the monomers glycolide and caprolactone. This material combines the strength of polyglycolic acid with the elasticity of caprolactone. Its degradation rate is relatively low, making it suitable when rapid degradation is not required. Polyglycolic acid-caprolactone is available on the market under the trade name Safil.

[0020] Polylactic acid (PLA) also degrades slowly, which is why it is particularly suitable for sensor units that require long-term monitoring over an extended period.

[0021] The carrier material is preferably porous to promote the fusion of tissue sections on both sides of the carrier. A mean pore size of at least 60 micrometers, preferably at least 100 micrometers, is considered advantageous. At least 60% of the pores larger than 20 micrometers should preferably be at least 60 micrometers in size. The mean pore size of the pores larger than 20 micrometers is ideally in the range of 100 to 400 micrometers.

[0022] However, the porosity can also be significantly finer. A medium pore size greater than 3 micrometers may also be advantageous.

[0023] Porosity also refers to the presence of deliberately introduced holes in the substrate, specifically corresponding to the pore size mentioned above. Holes with a mean diameter between 40 micrometers and 400 micrometers are particularly advantageous.

[0024] However, porosity is not strictly necessary. The healing process can also occur through the wearer if it begins to dissolve. Furthermore, the tissue can also heal around the wearer, and in the case of a ring, on the inside and / or outside.

[0025] The substrate features galvanically conductive traces that are either bioresorbable or at least biocompatible. These traces connect the sensor elements to other electronic components on the substrate and / or to a data line leading from the patient's body to an extracorporeal evaluation unit. The sensor elements can also be formed directly by the traces. In particular, the traces and / or the sensor elements can consist, at least in sections, of bioresorbable metal, especially magnesium (Mg), zinc (Zn), or iron (Fe). Magnesium can be used as the material for the trace or for the electrodes described below. However, it has been shown that, to prevent excessive oxidation, layers with a thickness of at least 90 micrometers should be used. 0100P0002WQ Page 4

[0026] Alternatively, biocompatible metals can be used which can remain at the site of tissue fusion without problems after healing is complete, especially gold (Au), silver (Ag) or platinum (Pt).

[0027] As an alternative to metallic conductor tracks, the conductor tracks and / or the sensor elements themselves can consist at least partially of conductive bioresorbable plastic, in particular PLA / PGA composites with conductive fillers, polypyrrole (PPy) with biodegradable dopants, conductive polyaniline (PANI), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), PEDOT:PSS or bioresorbable polyurethane.

[0028] The sensor unit, in particular its carrier and optionally the conductive traces, is designed to be resorbable. The carrier is preferably designed to decompose within a period of between 14 days and 6 months. Since it must be ensured in the immediate postoperative phase that the sensor elements continue to monitor the healing process and detect complications without being affected by the onset of decomposition, additional measures can be taken. For example, the carrier can be at least partially coated to delay the onset of decomposition or to extend the decomposition period. This coating can be applied by laminating the previously uncoated carrier, which already contains sensor elements, and the coating can, in particular, have cutouts in the area of ​​the sensor elements.

[0029] Suitable coating or lamination materials for delaying degradation include polylactic acid (PLA), polycaprolactone (PCL), polydioxanone, and poly(lactide-co-glycolide) (PLGA). These materials are bioresorbable but exhibit different degradation rates, allowing for targeted control of the carrier's absorption. Silk fibroin and calcium phosphates also offer slow degradation with high biocompatibility and are suitable for extending the period during which the carrier's degradation has not yet begun.

[0030] The use of such coating materials can make it possible to delay the resorption of the substrate in order to allow it to occur more quickly after decomposition of the coating.

[0031] The sensor elements, which are preferably placed at least partially between the connected tissue sections, can provide sensor data that can be associated with an insufficiency of 0100P0002WQ page 5

[0032] To reliably detect inflammation or similar complications at the connection point.

[0033] The flat and preferably planar carrier serves primarily to position these sensor elements at the desired measuring points. Depending on its design, the carrier also serves as a connection point for a data cable that exits the patient's body to evaluate the acquired data. Alternatively, the carrier can also house evaluation electronics and, if necessary, a transmission component for wireless signal transmission.

[0034] Regarding the sensor elements used: It is particularly preferred if at least one sensor element is arranged on the carrier as an impedance sensor. This sensor is designed to measure the electrical properties of the tissue, especially its conductivity, in order to draw conclusions about the healing process. Such an impedance sensor has two or more electrodes between which the conductivity is measured. The use of two electrodes is usually sufficient. However, since the contact resistance at the electrodes affects the voltage measurement, a design with three electrodes can be chosen to improve measurement accuracy. This allows the voltage measurement to be performed independently of the contact resistance of the electrodes, thus increasing the measurement accuracy.

[0035] Preferably, at least one of the electrodes is provided with a coating that reacts measurably to biomarkers. These biomarkers influence the electrodes by adhering to their surface and thereby altering electrical properties such as charge transfer resistance or capacitance. In this way, the biomarkers affect the impedance measurement, enabling various conclusions to be drawn.

[0036] Preferably, biomarkers can be used that change the pH value in the environment of the sensor via enzymatic processes, for example glucose oxidase, urease, and lactate oxidase, thus allowing the evaluation of the healing process.

[0037] The coating can be applied during the manufacturing process of the sensor unit. However, it is advantageous if the coating is applied to the electrodes shortly before a surgical procedure in which the sensor unit is implanted. 0100P0002WQ Page 6

[0038] The following describes a selection of possible biomarkers and the corresponding coatings for detecting these biomarkers.

[0039] A procalcitonin-specific coating can consist of antibodies that bind to procalcitonin when it is present in the body. The binding of this biomarker alters the charge transfer at the electrode surface, which affects the measured impedance and may indicate a bacterial infection.

[0040] A coating that reacts to interleukin-6 can also consist of antibodies that bind to this cytokine. When interleukin-6 is present in the environment, the impedance changes due to altered capacitance or resistance of the electrode, indicating an inflammatory response near the sensor unit.

[0041] A tumor necrosis factor-alpha-specific coating uses antibodies or aptamer molecules that bind to tumor necrosis factor. This interaction alters the charge transfer resistance at the electrode and influences the impedance, thereby enabling the detection of inflammatory processes.

[0042] A biomarker-specific coating for C-reactive protein (CRP) uses CRP antibodies that bind specifically to this protein. The binding of the protein to the electrode surface leads to a change in capacitance or resistance, which can be detected via impedance measurement and is an indicator of inflammation.

[0043] A coating that reacts to matrix metalloproteinases (MMPs) can, for example, be equipped with inhibitors or antibodies that recognize these enzymes. The interaction between the MMPs and the coating alters the surface properties of the electrode, which affects the impedance and thus provides information about the progress of wound healing or tissue remodeling.

[0044] A coating made of pH-sensitive materials reacts to changes in the pH value of the surrounding tissue. When the pH fluctuates, the electrical capacitance of the coating changes, which affects the impedance. This method allows for the detection of physiological conditions such as inflammation or tissue damage that are associated with pH changes.

[0045] This selection is to be understood as exemplary. Any coatings suitable for inferring inflammation from impedance measurements are eligible. 0100P0002WQ Page 7

[0046] In particular, sensor elements designed as impedance sensors are preferably arranged multiple times on the substrate. This will be described in more detail below.

[0047] It can also be advantageous to design at least one sensor element as a temperature sensor. Such a temperature sensor preferably has a thin metal film or a thin polymer film made of bioresorbable or biocompatible metal or polymer, the resistance of which depends on the temperature. This film is preferably applied directly to the substrate.

[0048] It can also be advantageous to provide a pressure sensor on the carrier to monitor the pressure in the area of ​​the anastomosis. The pressure sensor can be designed as a capacitive pressure sensor and comprises two electrodes whose distance changes depending on the pressure acting on the sensor. A dielectric material is located between the electrodes, which is compressed or deformed under the applied pressure.

[0049] A pressure sensor as part of the sensor unit can, for example, detect pressure changes that could indicate poor blood circulation or a scarred narrowing (stricture).

[0050] In the simplest case, the pressure sensor is located on one side of the substrate and connected there via the aforementioned conductor tracks. However, a design is also conceivable in which the pressure sensor has two electrodes arranged on opposite sides of the substrate. Depending on the pressure, the substrate, or a dielectric material applied to the substrate, causes a change in the electrode spacing on both sides of the substrate.

[0051] For the use of such pressure sensors, but also when using other sensors, it can be advantageous to have conductive traces and, if necessary, sensor elements on both sides of the substrate. It can be advantageous if at least one sensor element has a functional layer of PEDOT:PSS, poly(3-glycoloxythiophene) (p3gt), and / or polydiketopyrrolopyrrole (pdpp). These functional layers can be applied particularly to impedance sensors to improve their electrochemical properties and thus the sensor's performance.

[0052] As described at the beginning, the carrier has contact surfaces for the attachment of joined fabric sections on both sides. These contact surfaces do not need to cover the entire surface of the carrier on both sides. Only those parts of the carrier against which the fabric sections rest during use are designed as contact surfaces. The contact surfaces are preferably flat and may be slightly uneven due to the conductive traces or impedance sensors applied to the carrier.

[0053] A preferred configuration of the sensor system provides that the carrier has a main section from which several extension sections extend. The contact surfaces and at least one sensor element are located on each of these extension sections. The main section of the carrier is preferably not positioned directly between the tissue sections.

[0054] In particular, the aforementioned impedance sensors with at least two electrodes are preferably mounted on extension sections of the described type that are in direct contact with the connected tissue. Sensors where proximity to the contact point is less critical, such as the temperature sensor, can be placed on the main section of the carrier.

[0055] Preferably, in a state prior to use of the sensor unit, a plurality of extension sections are connected to one another by means of a connecting section. This supports the extension sections and facilitates handling. The connecting section is removed as intended during insertion into the human body, so that after removal of the connecting section, the extension sections protrude freely from the main section without further support.

[0056] A sensor system according to the invention is particularly intended for monitoring healing after anastomoses. To adapt it to this application, a design is preferably provided in which the carrier has an annular section or forms an annular section as a whole. Preferably, the outer diameter of this annular section is between 25 mm and 80 mm.

[0057] Such a ring-shaped carrier is particularly useful for anastomosis operation, as it can be arranged around the joint of the tissue or outside of it, thus allowing the circumferential arrangement of sensor elements.

[0058] Preferably, the annular section forms the main section, from which several extension sections extend towards the center of the annular section. When the sensor unit is inserted, the extension sections project from the outside into the tissue interface. 0100P0002WQ Page 9

[0059] As mentioned above, it is advantageous to have several identical sensor elements mounted at different locations on the substrate. In particular, a plurality of impedance sensors, each with at least two electrodes, can be provided.

[0060] In the case of a sensor element with an annular section, the sensor elements are preferably evenly distributed and spaced apart from each other on the annular section of the carrier. At least three sensor elements should be present in this arrangement.

[0061] In a design of the carrier with extension sections, the identical sensor elements are preferably attached to at least two or three of these extension sections, which extend inwards from the annular main section of the carrier.

[0062] Data transmission from the sensor unit inside the patient's body to the outside can occur either wirelessly or via a wired connection. Wireless transmission is possible, for example, via a radio transmitter based on electromagnetic induction, such as an NFC connection.

[0063] A preferred embodiment is one in which the radio transmitter consists entirely or predominantly of bioresorbable material or is at least constructed of biocompatible materials.

[0064] In this context, it is also possible to equip the sensor system with a battery. Such a battery should preferably also be bioresorbable or biocompatible. This can be achieved, for example, by using a magnesium or zinc anode and a molybdenum cathode. A saline solution can be used as the biocompatible electrolyte. The separator could, for example, consist of a bioresorbable polymer such as polyglycolic acid (PGA) or polylactic acid (PLA). These materials are also suitable for the battery casing.

[0065] The battery is typically sized to provide enough energy for the entire duration of the sensor unit's use within the patient's body. If recharging is necessary, this can be done wirelessly if the sensor unit has a receiving coil to absorb electrical energy from an extracorporeal transmitting coil. This coil can also be mounted directly on the carrier.

[0066] As an alternative to a wireless solution, a wired solution can be used. It is proposed that the sensor system has a transcutaneous data line via which a sensor unit implanted in a patient's body (0100P0002WQ, page 10) can be connected to an external evaluation device.

[0067] There are various options for its design.

[0068] One possibility is that the data cable has a connector that can be attached to the carrier via contact surfaces. This connector is either bioresorbable or it is removed along with the data cable during an explantation operation.

[0069] Another possibility is to design at least a portion of the data cable as a bioresorbable cable. Along with the sensor unit, the data cable is also resorbed within the body up to the point where it exits the patient's skin, so that the outer section of the data cable eventually falls off.

[0070] In this design, the data line can also have a carrier strand on which the conductor tracks are provided. This carrier strand could be integrally formed with the carrier of the sensor system.

[0071] Another preferred design provides that the data cable in an intracorporeal segment is designed as a non-bioresorbable cable, but can be removed without surgical intervention by connecting it to the sensor unit. In such a design, the non-bioresorbable data cable can be connected to the conductor tracks on the carrier via bioresorbable predetermined breaking points. These predetermined breaking points are gradually resorbed until the physical connection between the data cable and the sensor unit is completely severed. The non-bioresorbable portion of the data cable can then be withdrawn from the body.

[0072] The aforementioned predetermined breaking points preferably consist of a resorbable polymer and / or a resorbable metal.

[0073] The evaluation of sensor data can, in principle, be performed directly at the sensor unit inside a patient's body or by an external evaluation device. A combined evaluation is also conceivable, in which preprocessing is already carried out by a control unit that is part of the implanted sensor unit, while further processing is performed externally by a 0100P0002WQ page 11

[0074] Evaluation is performed. In particular, if the patient is not connected to an external evaluation device for certain periods, partial evaluation directly on the sensor unit is advisable, especially to be able to store recorded sensor data in a memory on the sensor unit for later retrieval.

[0075] The evaluation by a control unit of the sensor unit or by an external evaluation device serves the purpose of recognizing whether the sensor data reflects that the healing process is proceeding as desired or whether complications are occurring.

[0076] In particular, the evaluation can be carried out using the following functions:

[0077] The evaluation unit can be configured to analyze the signals from the sensor elements and generate a warning signal when a threshold is reached at one sensor element or cumulatively at several sensor elements. Exceeding the threshold is to be understood as an indicator of a complication. Generating a warning signal refers in particular to the immediate generation of a warning tone or a warning message.

[0078] The use of threshold values ​​represents a particularly simple form of evaluation.

[0079] It is advantageous to perform a calibration at the beginning of use to generate calibration data. This calibration data is used when evaluating the sensor signals to ensure that a warning signal is generated when the sensor data, in light of the calibration data, indicates a postoperative complication.

[0080] Preferably, the signals from at least two sensor elements are compared to detect a complication. In particular, sensor elements arranged symmetrically on the carrier can be considered together. A growing divergence in the signal values ​​of these sensor elements is a particular indicator of complications.

[0081] The sensor elements provide characteristic values ​​for the healing process based on two different mechanisms. The sensor data is preferably evaluated in a customized evaluation mode.

[0082] In the immediate postoperative phase, for example, 48 hours, bioresorption of the sensor unit's components does not yet occur. The sensor data is therefore primarily influenced by potential inflammation, which can be detected particularly using impedance sensors (page 12), especially with multiple widely distributed impedance sensors. In particular, leakage in the sutured tissue sections can lead to such inflammation.

[0083] During the subsequent healing phase, lasting for example several weeks, the signals from the sensor elements also depend on their bioresorption. The bioresorption of conductive traces, for instance, leads to the complete loss of sensor signals. Partial bioresorption of electrodes results in changes in impedance measurements that are characteristic of the healing process and therefore allow conclusions to be drawn about it.

[0084] BRIEF DESCRIPTION OF THE DRAWINGS

[0085] Further advantages and aspects of the invention will become apparent from the claims and from the following description of preferred embodiments of the invention, which are explained below with reference to the figures.

[0086] Fig. 1 shows a first embodiment of a sensor system according to the invention.

[0087] Figures 2A and 2B show the sensor unit of the sensor system before and after implantation.

[0088] Figures 3 and 4 show the arrangement of the sensor unit during implantation.

[0089] Figures 5 to 7 show alternative embodiments.

[0090] DETAILED DESCRIPTION OF THE EXECUTION EXAMPLES

[0091] Fig. 1 shows a first embodiment of the sensor system 10 according to the invention.

[0092] The sensor system 10 has a sensor unit 20, which is intended to be inserted at a tissue joining site in order to monitor the healing process and detect insufficiencies. In particular, the sensor system shown here is intended for the detection of insufficiencies in intestinal anastomosis.

[0093] A data line 22 connects to the sensor unit 20. In a section 22A, up to a boundary 2 formed by the exit point, the data line has a carrier strand 23 that is integrally formed with the carrier of the sensor unit 20. 0100P0002WQ Page 13

[0094] Outside the body, the data line 22 is formed by a section 22B, which leads to an evaluation unit 90. This evaluation unit is designed to evaluate the data acquired by sensor elements of the sensor unit 20 and, in the event of possible complications, to indicate this by means of a warning LED 92.

[0095] Figures 2A and 2B show the sensor unit 20 as depicted in Figure 1. The main element of the sensor unit 20 is a flat, porous carrier 30 made of porous, bioresorbable material, such as polydioxanone. This carrier 30 has an annular main section 31, 32, from which spoke-like extensions 34 extend inwards.

[0096] Figure 2A shows the operating state of the sensor unit when implanted. Figure 2B shows a preliminary state, which differs from the operating state in that the extension sections 34 are still connected by a common connecting section 36 of the carrier. During implantation, this connecting section 36 is removed, resulting in the state shown in Figure 2A, in which the extension sections project freely inwards.

[0097] Conductive traces 50 are mounted on the carrier 30 and its extensions 34. These conductive traces 50 fulfill various functions. Some of these conductive traces lead to three impedance sensors 40, each with two electrodes 40A, 40B. The electrodes are each coated with a coating 40C, which influences the measurement results of the impedance sensors and, depending on the coating, reveals various complications.

[0098] The electrodes and conductive traces can be applied to the polydioxanone substrate using printing processes (screen printing or inkjet printing, piezoelectric printing, or bubble jet printing). To improve the adhesion of the conductive traces and electrodes to the substrate, surface treatment with plasma or other surface activation methods, such as electron beam activation, can be advantageous. This treatment creates a negatively charged surface, which enhances adhesion. An alternative application method to printing for the electrodes and / or conductive traces is vapor deposition.

[0099] The impedance sensors 40 are each placed on one of the three provided extension sections 34.

[0100] Furthermore, the sensor unit 20 has a temperature sensor 42, which is also connected to the carrier by two conductor tracks 50. The temperature sensor 42 consists of a thin metallic layer (see page 14) which is arranged in a meandering shape on the carrier to increase its length.

[0101] As a third sensor type, the carrier 30 according to Fig. 2A has a pressure sensor 44. This is shown in a simplified form in the figures. Preferably, the sensor is designed as a capacitive sensor, which has two electrodes that change their distance under pressure and thus make the pressure measurable.

[0102] Figures 3 and 4 illustrate the intended arrangement of the sensor unit 20.

[0103] The sensor unit 20 is positioned directly at the joining point of the intestinal ends 100A, 100B. The ring-shaped section 31, 32 is chosen to be larger than the intestinal diameter, so that only the extensional sections 34 themselves, with their two contact surfaces 32A, 32B, come into contact with the tissue sections to be joined.

[0104] Fig. 4 illustrates this. It shows how the extension sections 34 are placed from the outside into the intermediate area between the ends of the intestinal ends 100A, 100B, whereby the joining means (seam, staples 102) that connect the two intestinal ends 100A, 100B to each other can penetrate the carrier 30 of the sensor unit 20.

[0105] As part of the healing process, the two intestinal ends 100A, 100B grow together, and this also occurs through the carrier 30.

[0106] In the event of insufficiency of the connection point, intestinal contents can enter the abdominal cavity, typically causing inflammatory reactions in the immediate vicinity of the suture site.

[0107] The impedance sensors 40 mounted on the carrier 30 detect an impedance value that makes such inflammatory reactions detectable, especially when one of the coatings described above is applied to the electrodes of the impedance sensor.

[0108] Figures 5, 6 and 7 show alternative designs of the sensor system 10.

[0109] In Fig. 5, it is provided that at least a subsection 22C of the data line 22, which is located inside the patient's body in the implanted state, is not designed as a bioresorbable data line.

[0110] Instead, it is provided that conductor tracks 50 are attached to the carrier 30 or to an outwardly directed extension, which are connected via absorbable connection points, such as solder joints, 0100P0002WQ page 15 to the signal lines of subsection 22C of the data line 22. These connection points form predetermined breaking points 24.

[0111] The result is that the sensor unit 20, including the predetermined breaking points 24, is resorbed in the patient's body, while the subsection 22C remains. This remaining subsection 22C can then be removed from the patient's body after the sensor system 10 has been used.

[0112] Fig. 6 shows a configuration in which a section 22D of the data line 22 is provided at its end with a non-resorbable connector 27. This connector can be slid onto the corresponding contacts of the conductor tracks 50 to connect the evaluation unit 90 to the sensor unit 20. Such a connector must either be bioresorbable itself or be removed during an explantation operation after completion of the healing process.

[0113] Fig. 7 shows a configuration of the sensor system 10 in which no data line is provided and a radio connection is used instead. In this case, a preferably bioresorbable evaluation chip 49 is mounted on the carrier 30, which is powered by a bioresorbable battery 48 and enables data communication with the external evaluation unit 90 via a bioresorbable radio transmitter 46.

Claims

0100P0002WQ Page 16 Patent claims 1. Sensor system (10), in particular for monitoring the healing process after an anastomosis, especially an intestinal anastomosis, with the following features: a. the sensor system (10) has a flat carrier (30) made of a resorbable material on which sensor elements (40, 42, 44) are arranged, and b. on both sides (30A, 30B) of the carrier (30) a contact surface (32A, 32B) is provided for the bilateral contact of joined tissue sections, the healing of which is monitored by means of the sensor system (10), and c. on at least one side (30A, 30B) of the carrier (30) bioresorbable or biocompatible conductor tracks (50) are provided which are electrically connected to the sensor elements (44) or directly form the sensor elements (40, 42).

2. Sensor system (10) according to claim 1 with the following further feature: a. the flat carrier (30) is made of a porous, resorbable material.

3. Sensor system (10) according to claim 1 or 2 with the following further features: a. at least one sensor element (40) is designed as an impedance sensor, which is intended to measure electrical properties of the tissue, in particular its conductivity, in order to draw conclusions about the healing process, and b. the impedance sensor has at least two electrodes (40A, 40B), preferably with the following further feature: c. a coating (40C) is applied to at least one of the electrodes (40A, 40B) which reacts measurably to certain biomarkers, wherein the coatings are preferably for one of the following detections: Procalcitonin for the detection of bacterial infections, interleukin-6 for the detection of inflammatory reactions, 0100P0002WQ Page 17 Tumor necrosis factor alpha for the detection of inflammatory reactions, C-reactive protein for the detection of inflammatory reactions, matrix metalloproteinases for the detection of wound healing / tissue regeneration, or pH-sensitive materials for the detection of the pH value of the adjacent tissue.

4. Sensor system (10) according to claim 1, 2 or 3 with the following further feature: a. at least one sensor element (42) is designed as a temperature sensor, preferably with the following additional feature: b. the temperature sensor (42) has a thin metal film or a thin polymer film made of bioresorbable or biocompatible metal or polymer, the resistance of which depends on the temperature.

5. Sensor system (10) according to one of the preceding claims with the following additional feature: a. at least one sensor element (44) is designed as a pressure sensor, in particular with the following additional features: b. the pressure sensor (44) is designed as a capacitive pressure sensor and comprises two spaced-apart electrodes (44A, 44B) whose spacing can be changed depending on a pressure acting on the pressure sensor, and / or c. the pressure sensor (44) is provided on one of the sides (30A, 30B) of the carrier, or d. the pressure sensor has two electrodes which are provided on opposite sides of the carrier. 0100P0002WQ Page 18 6. Sensor system (10) according to one of the preceding claims with the following further feature: a. at least one sensor element (40) has at least one functional layer of PEDOT:PSS, poly(3-glycoloxythiophene) and / or polydiketopyrrolopyrrole.

7. Sensor system (10) according to one of the preceding claims with the following additional feature: a. the carrier (30) has a main section (32) from which a plurality of extension sections (34) of the carrier (30) extend, on which the contact surfaces (32A, 32B) are provided and on which at least one sensor element (40) is provided, preferably with the following additional feature: b. a plurality of extension sections (34) is connected to each other by means of a connecting section (36), wherein the connecting section (36) is removed as intended during insertion into the human body, so that the extension sections (34) project freely away from the main section (32) after removal of the connecting section (36).

8. Sensor system (10) according to one of the preceding claims with the following further feature: a. the carrier (30) has an annular section (31) or forms an annular section (31) as a whole, preferably with one of the following additional features: b. the annular section (31) has an outer diameter between 25 mm and 80 mm, and / or c. the annular section (31) forms the main section (32) from which a plurality of extension sections (34) extend towards a center of the annular section. 0100P0002WQ Page 19 9. Sensor system according to one of the preceding claims with the following further feature: a. the carrier (30) is formed at least partially from one of the following materials: Polydioxanone, and / or Polyglactin, in particular polyglactin 910, and / or Polyglycolic acid, and / or Poliglecaprone 25 and / or Polyglycolic acid caprolactone and / or Polylactide.

10. Sensor system according to (10) one of the preceding claims with the following further feature: a. the conductor tracks (50) and / or the sensor elements (40, 42, 44) are formed by a galvanically conductive layer applied to the carrier (30), preferably with at least one of the following features: b. the conductor tracks (50) and / or the sensor elements (40, 42, 44) are formed at least partially from bioresorbable metal, in particular magnesium, zinc or iron, and / or c. the conductor tracks (50) and / or the sensor elements (40, 42, 44) are formed at least partially from biocompatible metal, in particular gold, silver or platinum, and / or d.the conductor tracks (50) and / or the sensor elements (40, 42, 44) are formed at least partially from conductive bioresorbable plastic, in particular from PLA / PGA composites with conductive fillers, from polypyrrole with biodegradable dopants, from conductive polyaniline, from poly(3-hydroxybutyrate-co-3-hydroxyvalerate), PEDOT:PSS or from bioresorbable polyurethane. 0100P0002WQ Page 20 11. Sensor system (10) according to one of the preceding claims with the following further feature: a. a plurality of identical sensor elements (40) are provided, which are mounted at different locations on the carrier (30), preferably with at least one of the following further features: b. the sensor elements (40) are arranged spaced apart from one another around the ring-shaped section (31) of the carrier (30), wherein preferably at least three sensor elements (40) are provided, and / or c. the sensor elements (40) are mounted on a plurality of extension sections (34) which extend from a main section (32) of the carrier (30).

12. Sensor system (10) according to one of the preceding claims with the following further feature: a. the sensor system (10) comprises a bioresorbable or biocompatible radio transmitter (46), preferably with one of the following additional features: b. the sensor system (10) comprises a battery (48), and / or c. the sensor system comprises a receiving coil for receiving electrical energy from an extracorporeal transmitting coil.

13. Sensor system (10) according to one of the preceding claims with the following further feature: a. the sensor system (10) has a transcutaneous data line (22) by which a sensor unit (20) of the sensor system (10) implanted in the body of a patient can be connected to an evaluation device (90) outside the body of the patient, preferably with one of the following further features: 0100P0002WQ Page 21 b. the data line (22) has a connector (27) which can be connected to the carrier (30) by means of contact surfaces, or c. the data line (22) is designed as a bioresorbable data line at least in a partial section (22A), wherein in particular preferably a carrier strand (23) of the data line (22) is formed integrally with the carrier (30) of the sensor system (10).

14. Sensor system (10) according to claim 13 with the following further feature: a. the data line (22) is designed at least in a subsection (22C) as a non-bioresorbable data line and is connected to conductor tracks (50) on the carrier (30) via bioresorbable predetermined breaking points (24), wherein the predetermined breaking points (24) preferably comprise a resorbable polymer and / or a resorbable metal.

15. Sensor system (10) according to one of the preceding claims with the following further feature: a. The sensor system (10) has an evaluation unit (90) which is connected via a data line (22) to a sensor unit (20) of the sensor system (10) and is configured for evaluating measurement signals from the sensor elements (40, 42, 44), wherein the evaluation unit (90) has at least one of the following functions: the evaluation unit (90) is configured to evaluate the signals from the sensor elements (40, 42, 44) and to generate a warning signal when a threshold value is reached at one sensor element (40, 42, 44) or cumulatively at several sensor elements (40, 42, 44), and / or the evaluation unit (90) is configured to perform a calibration, thereby generating calibration data and generating a warning signal depending on the signals from the sensor elements (40, 42, 44) relative to this calibration data.and / or the evaluation device (90) is designed to compare signals from at least two sensor elements (40, 42, 44) with each other, in particular two sensor elements (40, 42, 44) arranged symmetrically to each other on the carrier (30), and to generate a warning signal depending on a divergence of the signals. 0100P0002WQ Page 22 the evaluation device (90) has at least two evaluation modes, wherein in a first evaluation mode, which is intended for the immediate postoperative phase, signals from the sensor elements (40, 42, 44) are evaluated to determine whether they indicate a leakage of the joined tissue sections, and wherein in a second evaluation mode, which is intended for the subsequent healing phase, signals from the sensor elements (40, 42, 44) are evaluated as an indicator of the intended decomposition of the bioresorbable sensor elements during the healing process.

16. Sensor system (10) according to one of the preceding claims with at least one of the following further features: a. the carrier (30) is made of a material with a mean pore size of at least 60 micrometers, preferably at least 100 micrometers, and / or b. the carrier (30) has a plurality of holes with a mean diameter between 40 micrometers and 400 micrometers, and / or c. the carrier (30) is designed to be degradable within a period of between 14 days and 6 months, wherein preferably the carrier is at least partially provided with a coating to extend the degradation period.

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