Patent Application
20230181047
The present invention relates to a medical device provided with sensors. The invention also relates to a medical system comprising such a medical device and a method for querying such a medical device, particularly in a medical system.
The invention particularly relates to an implantable medical device such as a stent (sometimes also referred to as “arterial endoprosthesis”, “vascular stent”, or simply “spring”) provided with sensors.
A stent is a device of tubular shape produced by a deformable mesh, particularly made of metal or of a biodegradable polymer material. The stent is inserted into a patient's body in a folded state, with the meshes closed, and is then extended inside the patient's body, for example by angioplasty which triggers the deployment of the meshes. The stent, once deployed, helps keep a cavity open in the patient's body. It is known that fitting a stent may particularly cause tissue inflammation, hyperplasia and/or blood clotting.
Consequently, a stent may be provided with sensors, which make it possible to monitor the state of the tissues around the stent to, optionally, adapt the patient's treatment accordingly. Sensors may also be provided to ensure that the stent fulfils the function thereof of keeping a cavity open.
It is known to query a stent, i.e. collect information from this stent, using a contactless querying device, retained outside the patient. Generally, such a contactless querying device is configured to measure an electromagnetic field emitted by the stent implanted in the patient.
The patent EP-B-2 271 933 as such describes a method for characterising cells in the vicinity of a medical device implanted in a patient, particularly a stent, using impedance measurements at different frequencies.
The application WO-A-2009/1 361 677 describes an implantable medical device such as a stent, having an electrically conductive surface and an impedance sensor for measuring the impedance of the conductive surface of the implantable medical device, at different frequencies, using the conductive surface as an electrode. The measurements made are used to determine the degree of restenosis of the tissues at the level of the implantable device, i.e. the tissue thickness having grown at the level of the conductive surface of the implantable medical device.
These documents disclose methods providing overall information on the implantable device, without making it possible to obtain independently the measurements made by each sensor with which the implantable medical device is provided.
Moreover, it is known from U.S. Pat. No. 8,478,378, a stent provided with sensors distributed on the inner surface thereof, oriented towards the passage through the stent, or “luminal” surface. The sensors are configured to send a specific characteristic output signal in response to an excitation. The specific characteristic signal may particularly be a wavelength specific to each of the sensors. U.S. Pat. No. 8,478,378 indicates that as such an output signal including signals from all or most of the sensors suggests that a large number of sensors are not coated with a layer of endothelial cells.
The application DE-A-101 03 503 discloses a stent comprising electrodes for measuring the impedance of tissue in contact with the stent where each set of electrodes is associated with a multiplexer controlled by a control circuit. Implanting such multiplexers renders the stent structure complex.
It is known from the applications US-A-2011/0054583 and US-A-2012/0190989 a sensor array topology in a stent. Such a topology enables addressing of the sensors by row and by column, enabling activation of the sensors in a reconfigurable manner and independently from one another.
Finally, the application WO-A-2011/121581 describes an implantable medical device capable of responding to an electromagnetic query field emitted by a remote querying device. The implantable medical device is provided with a plurality of modulators consisting of RFID (“Radio-Frequency Identification”) chips, RFID chips arc suitable for the implantable medical device to respond to an electromagnetic query field according to a modulation generating a unique respective identification code.
The use of RFID chips as sensors in the medical device limits however the number of sensors with which it may be provided. The multiplication of the RFID chips indeed increases the price of the medical device accordingly. Moreover, according to this document, the medical device must be at least partially made of a metallic material having good electrical conduction. Finally, according to this document, the RFID chips must be implanted in the very structure of the implantable medical device, rendering the embodiment thereof particularly complex.
Implantable medical devices are also known from WO-A-01/37 726 or U.S. Pat. No. 6,206,835. These medical devices include a structure implantable in the body to assist with carrying out a vital function in the body. One or a plurality of sensors are associated with this implantable structure, which make(s) it possible to measure a parameter associated with the structure. Finally, these medical devices include a communication circuit coupled with the sensor(s) to deliver a signal according to the parameter measured and to transmit this signal to a receiving device, outside the body, non-invasively.
The aim of the invention is that of remedying the problems mentioned above. In particular, the aim of the invention is that of providing a medical device having a simple structure and therefore limited cost, suitable for distinguishing the quantities measured by various sensors with which the medical device is provided. In one preferred embodiment, the medical device is implantable in the patient's body and configured to make it possible to determine, without intruding the patient's body, whether it is implanted correctly.
The invention relates to a medical device comprising an electrical measurement circuit, wherein are connected at least two variable-impedance sensors according to a detected physical quantity, an electrical power source for supplying power to the electrical measurement circuit, an antenna for emitting an electromagnetic field according to the impedance of the electrical measurement circuit, each of the sensors being associated with a switch for interrupting the current supply of the sensor in said measurement circuit, the medical device further comprising a system for controlling the switches in order to successively control the opening or the closing of the switches, according to determined configurations.
As such, according to the invention, the medical device is provided with any type of variable-impedance sensors connected to one another in a so-called measurement circuit. A control system makes it possible to switch off the current supply of the various sensors according to predetermined configurations, such that the electromagnetic field emitted by the medical device corresponds to the configuration of the measurement circuit. By carrying out successive measurements, corresponding to linearly independent configurations—for example one sensor disconnected from the circuit at a time or all the sensors disconnected from the circuit at a time except one—it is very readily possible to obtain qualitative information on the values measured by each of the sensors of the medical device, arranged at known locations on the medical device.
The term “disconnecting a sensor from the circuit” denotes hereinafter creating a circuit configuration such that the current passing through the sensor is nil, the other sensors being capable of being supplied with current. The sensor is for example disconnected from the circuit by being short-circuited per se or disconnected from the circuit by opening the sensor circuit, i.e. the sensor is disconnected from the circuit thereof. In other words, “disconnecting a sensor from the circuit”, in both scenarios, denotes herein switching off the current supply of this sensor.
Preferably, the medical device includes one or a plurality of the following features taken alone or in combination:
The invention also relates to a medical system comprising a medical device as described above in any combinations thereof and a unit for receiving information from the medical device, comprising means for sensing the electromagnetic field emitted by the antenna of the medical device.
The medical system may further comprise a unit for querying the medical device, preferably merged with the unit for receiving information, preferably comprising means for emitting an electromagnetic field suitable for creating an induced current in the measurement circuit of the medical device.
The medical system may comprise a comparator intended to compare an identifier emitted by the querying unit, with a binary code associated with a given combination of fixed impedances of the measurement circuit of the medical device.
The medical system may further comprise a unit for processing the information received by the reception unit, for example a computer, the unit for processing information preferably having a screen to display in real time a model of the medical device whereon is transferred information relating to the values of the measurements made using the sensors.
The invention also relates to a method for querying a medical device as described above in any combinations thereof, particularly in a medical system as described above in any combinations thereof, comprising steps consisting of:
The method may comprise a step for identifying the medical device.
The method may also comprise a calibration step prior to each measurement or prior to certain measurements of the magnetic field emitted by the antenna of the medical device, corresponding to the magnetic field emitted by the antenna according to the current passing through the impedances and/or the elements of fixed and known impedance.
The appended figures will help understand clearly how the invention may be embodied. In these figures, identical references denote similar elements.
Hereinafter in the description, elements that are identical or have an identical function bear the same reference sign in the various embodiments. For the purposes of conciseness of the present description, these elements are not described with regard to each of the embodiments, only the differences between the embodiments being described.
The implantable medical device 12 includes a variable impedance 15. The value of this variable impedance 15 is controlled by a control unit not shown, according to the impedance in a measurement circuit 16, connecting particularly the various sensors 22 of the implantable medical device. The implantable medical device 12 further includes an electrical power source, herein a source of electric current formed by the body 18 of the implantable medical device 12. Indeed, under the effect of an electromagnetic field emitted by the querying unit 14, the body 18 of the implantable medical device 12 induces a current. Alternatively, an antenna or armature separate and electrically insulated from the body 18 of the implantable medical device 12 may also be provided, particularly in the case wherein the implantable medical device 12 is not suitable, completely or partially, for having an armature function. In the latter case in particular, an electrical power source for the measurement circuit may include a current-conducting surface of the implantable medical device, suitable for inducing an electric current under the effect of an electromagnetic field. An electric battery or cell may also be provided as an electrical power source for the implantable medical device 12.
The body 18 of the implantable medical device 12 serves herein also as an emitting antenna, to emit an electromagnetic field outside the body wherein the implantable medical device is implanted. For example, at a constant induced current intensity of the electrical power source, the intensity of this field is directly dependent on the variable impedance 15, according to the impedance in the measurement circuit 16. As such, the intensity or a standard of the electromagnetic field emitted by the body 18 of the implantable medical device 12 (or more generally of the emitting antenna) is dependent on the impedance of the measurement circuit 16. Alternatively, the implantable medical device 12 may include an antenna separate from the body of the implantable medical device or the antenna may be formed by a part at least of the implantable medical device.
The implantable medical device 12 is for example a stent. The stent is a tubular metal device, preferably meshed, inserted into a natural human (or animal) cavity to keep it open, as described above in the introduction. The stent may for example be made of a metal alloy or polymer material, but other materials may also be envisaged.
The implantable medical device 12 is provided with variable-impedance sensors 22 according to the physical quantity detected thereby. The term physical quantity denotes herein any property of natural science which may be quantified by measurement or computation, and the different possible values whereof are expressed using any real number or a complex number. A physical quantity includes therefore, for example, a length, an electric current, a voltage, an impedance, a concentration of a chemical element or even the presence and/or concentration of a biological or biochemical element.
The sensors 22 are distributed on the surface of the implantable medical device. In the particular case of the stent described herein, the sensors 22 may particularly be distributed:
The sensors may be coated with an active agent, for example to limit hyperplasia of the tissues in contact with the implantable medical device, particularly when they are positioned on the abluminal surface of a stent or more generally on the outer surface of an implantable medical device intended to be in contact with the wall of the cavity wherein the medical device is implantable.
It should be noted that positioning a single sensor, particularly a pressure sensor, on the abluminal surface of a stent, or more generally on the outer surface of an implantable medical device already makes it possible to obtain information relating to the poor positioning of the stent or implantable medical device in the cavity. If the pressure measured is low (i.e. less than a threshold pressure), it is likely that the sensor is not in contact with a wall of the cavity, but rather with blood, for example. In the case where two sensors or more are arranged on the abluminal or outer surface, the information may be obtained with more precision by comparing the values measured by the sensors with one another.
Preferably, the sensors are arranged at the locations of the implantable medical device, particularly a stent, subject to the least deformations during the fitting of the implantable medical device, in order to avoid damaging the sensors. As such, although
Each of the sensors may particularly be chosen from:
The sensors 22 are variable-impedance sensors, i.e. sensors wherein the impedance varies according to the amplitude or intensity of the physical quantity detected. Hence, in the event of variation of the amplitude of the physical quantity detected by a sensors of the implantable medical device 12, the impedance of this sensor varies in the measurement circuit 16, such that, in the absence of any other variation in the measurement circuit 16, the impedance of the measurement circuit 16 also varies.
As illustrated, each sensor 22 is associated with a switch 24 suitable for disconnecting from the circuit, in this instance short-circuiting, the sensor 22 with which it is associated. Herein, this is carried out by mounting the switch 24 in derivation (or in parallel) with the sensor 22 with which it is associated. The sensors 22 are herein mounted in series in the measurement circuit 16. For reasons of ease of embodiment and miniaturisation, each switch is herein embodied by a transistor 24, in this instance a silicon MOS-FET transistor, more specifically a depletion-mode, P-channel MOS-FET (or p-MOS) transistor. In further embodiments, each switch or certain switches may be embodied by another type of transistor, particularly by a FET transistor, an enhancement-mode MOS-FET transistor, particularly an enhancement-mode N-channel MOS-FET transistor, by a MEMS (standing for “Micromechanical system”), or by a mechanical switch.
In this instance, the control system 26 is configured to normally keep the switches 24 closed and to open same successively and then to close them again such that, at each time, a single switch 24 is open.
For this purpose, each control module 28 is formed herein of a logic circuit, embodied by means of transistors 30, 32, 34, 36, 38, a resistor 40 and a capacitor 42. The resistor 40 and the capacitor 42 introduce a charging time of the capacitor 42 and a discharging time of said capacitor 42 in the logic circuit. During these charging and discharging times, the control module 28 controls the opening of the associated switch 24. The switch 24 is kept closed for the rest of the time, thereby short-circuiting the associated sensor 22.
More specifically, and as shown in
When the voltage applied at the input of the first inverter is close to zero, therefore less than the threshold voltage of the transistors 30 and 32, the PMOS type transistor 32 is switched to the ON-state, charging the capacitor 42. At the end of the charging thereof, the voltage at the input of the second inverter is greater than the threshold voltage of the transistors 36 and 38, rendering the NMOS type transistor 36 ON. A voltage close to zero is transmitted at the output of the second inverter connected to the gate of the PMOS type transistor 34. The latter is then switched to the ON-state, transmitting a voltage close to zero to the gate of the PMOS type switch 24, which triggers the closing thereof. While a voltage close to zero is applied to the input of the first inverter, the switch 24 is kept closed.
When a voltage greater than the threshold voltage of the transistors 30 and 32 is applied at the input of the first inverter, the NMOS type transistor 30 is switched to the ON-state, transmitting to the output thereof the ground potential, which triggers the discharging of the capacitor 42. During this discharging, the voltage at the input of the second inverter decreases until it becomes less than the threshold voltage of the transistors 36 and 38, inhibiting the transistor 36 and activating the transistor 38. The latter thereby transmits to the output of the second inverter a potential greater than the threshold voltage of the transistor 34, triggering the inhibition thereof. Consequently, the switch 24 opens. As such, by applying a high positive voltage at the input of the first inverter of the first control module 28, the opening is induced of the switch 24 which is connected thereto, followed by the successive opening of the switches 24 connected to the subsequent control modules 28. The start circuit, not shown, powering the input 46 of the first module is configured to generate a crenelated voltage pulse for a time interval τ=RC. The trailing edge of this pulse induces the closing of the switch of the first module after a time equal to τ. The voltage pulse is propagated from one input 46 to another, such that the trailing edge of this pulse at the input of a module n corresponds to the leading edge of the pulse at the input of the module n+1. As such, in this instance, during the propagation of the pulse, all the switches are closed except one.
With such a control system, the voltage at the terminals of the measurement circuit 16, which is equal to the sum of the voltages at the terminals of each of the sensors mounted in series in the measurement circuit, exhibits successive peaks which are representative of the voltage at the terminals of each of the sensors. To each of the successive peaks, each representative of the voltage at the terminals of a sensor 22, corresponds an intensity of the electromagnetic fields emitted by the body 18 of the implantable medical device 12 having an emitting antenna function.
In
The measurement circuit 16 is moreover completed in
Alternatively, according to the embodiment represented partially and schematically in
Alternatively, obviously, it is possible to embody a control module 28 having a different operation, which controls the closing of the switch 24 during a time interval only, the switch 24 being open the rest of the time. Such an operation may also be obtained by retaining the control module 28 as described above and by replacing the depletion-mode MOS-FET transistors used as switches 24 by enhancement-mode MOS-FET transistors.
Herein, as represented in
As for the preceding examples, due to the configuration of the modules 62, each sensor 22 and impedance 66 is successively connected to the antenna 18 in order to be powered, the other sensors 22 and impedances 66 being for their part disconnected.
Finally,
Obviously, it is possible to conceive a structure where the measurement circuit 16 is connected directly to the antenna, the implantable medical device also comprising a control circuit associated with this measurement circuit and as described for example with regard to
In practice, in the embodiments described above, each module may particularly by embodied in the following form. Two measurement electrodes, for example of 60×60 μm2, made of an electrically conductive material, for example of polymer material or of metal alloy, preferably biocompatible, are deposited on an electrically insulating, biocompatible polymeric substrate (for example parylene). The electrical components of the control system and the switch are implanted in the polymeric substrate.
The medical systems described above are suitable for carrying out a querying method 500 of the implantable medical device 12, as shown by the flow chart in
This method 500 includes a first step 502 consisting of powering the measurement circuit 16. Preferably, this power supply is carried out by an induced current in an antenna or in the body of the implantable medical device 12 when the latter is configured to generate an induced current. This makes it possible to power the measurement circuit 16 only when a measurement is made.
The method 500 is continued by a step 504 consisting of activating the system for controlling the implantable medical device so that it successively controls the opening of the closing of each of the switches of the implantable medical device, according to determined configurations. It should be noted herein that within the scope of the examples described with regard to the figures, this activation is carried out simultaneously with the power supply of the measurement circuit 16, by induction, in response to the emission of an electromagnetic field by the querying device. The method 500 then includes a step 506 for identifying the queried medical device. This step may, alternatively, be carried out before electrically powering the measurement circuit.
The identification may be carried out either in the medical device per se, when the latter is provided with a comparator to compare an identification signal emitted by the querying unit with a unique identifier of the medical device. As indicated above, this identifier may take the form of a combination of known impedances in the medical device and/or in each measurement line of the medical device. The identification may be carried out iteratively, the querying unit merely emitting one digit of the identifier at a time, each of the medical devices wherein the identifier does not correspond to this digit being temporarily deactivated (i.e., in the example studied, not electrically powered).
Alternatively, the identification is carried out in the processing unit, the signals emitted by the antenna 18 being interpreted by the processing unit to determine the combination of the impedances of the medical device and/or of the measurement line queried. A processing unit may be used to determine the value measured by each sensor and the implantable medical device that responded to the query, particularly if the controlled configurations of the measurement circuit are more complex.
To do this, the processing unit may particularly be suitable for conducting Fourier analyses of the measured signals of electromagnetic fields emitted by the antenna of the implantable medical device, comparing the signals received (optionally processed) to previously measured signals and inferring therefrom the values measured by the various sensors of the implantable medical device, one location being suitable for being determined for each of the values measured.
If the identification is negative, the medical device is temporarily deactivated, in the step 508.
If the identification is positive, the method 500 is continued then by a step 510 consisting of measuring the electromagnetic field emitted by the antenna of the implantable medical device. This measurement is made over a relatively long time so that the control system will have been able to control a relatively large number of different configurations of the measurement circuit so that the measurement makes it possible to determine the value measured by each of the sensors 22 of the implantable medical device 12. Throughout the measurement step, the antenna 14 preferably emits a constant electromagnetic field to maintain the power supply of the measurement circuit 16 and the activation of the control system 26.
Preferably, each configuration corresponds to the scenario where all the sensors or impedances of the measurement circuit are disconnected from the circuit, except one. As such, on the basis of the electromagnetic field measured, it is possible to determine first of all the implantable medical device that responded to the query. Indeed, the first peaks measured in the electromagnetic field emitted by the antenna correspond to fixed impedances, the combination whereof makes it possible to identify the implantable medical device. These magnetic fields measured may also be suitable for calibrating the system since the magnetic fields measured correspond to known impedances of the measurement circuit. Finally, the subsequent magnetic fields make it possible to determine the values measured by each of the sensors distributed on the implantable medical device.
When elements 60A are envisaged between the sensors 22, the corresponding magnetic fields emitted may be used to calibrate the following and/or preceding emitted signal, which originates from a measurement by a sensor 22.
Once all the sensors 22 of the medical device 12 have been queried, the electrical power supply of the electrical circuit is switched off and the electrical circuit of the medical device 12 is deactivated.
It should be noted herein that the method described may be used with any type of variable-impedance sensor according to the physical quantity detected thereby. It should also be noted that the sensors distributed on the implantable medical device may be of different types, i.e. they may detect different physical quantities.
The method described above may particularly be used to determine whether the implantable medical device is suitably implanted (i.e. positioned) in the natural cavity that it is supposed to keep open, in particular, if it is indeed in contact with the wall of the cavity. Indeed, the effect of a stent, for example but this is true for most implantable medical devices, is markedly reduced if the latter is not bearing on the wall of the cavity (particularly of the vein or the artery) wherein it is inserted.
For example, by placing pressure sensors on the abluminal surface of the stent, i.e. on the surface opposite the lumen through the stent, that which is intended to be in contact with the wall of the cavity wherein the implantable medical device is received, the method described above makes it possible to determine whether each of these sensors is in contact with the wall, since it makes it possible to determine the pressure measured by each of the sensors. Obviously, this function for determining the suitable position of the stent may be combined, that is to say that sensors, for example of pressure, may be arranged on the abluminal surface of the stent and sensors, optionally of another physical quantity, may be arranged on the luminal surface of the stent.
Alternatively, sensors of the same physical quantity are distributed on the abluminal surface and on the luminal surface, substantially at the same position on the stent or implantable medical device. In other words, sensors of the same physical quantity are arranged at the same point of the stent, on either side of the stent body. The comparison of the values measured by each of these stent pairs also makes it possible to obtain indications of an incorrect position of the stent in the cavity. In particular if the sensor on the abluminal surface, which should therefore be in contact with a wall, measures a substantially identical value to the sensor on the luminal surface, which is in contact with the blood, it is likely that the sensor on the abluminal surface is in fact in contact with blood also, not with a wall. It is therefore likely that the stent is poorly positioned in the cavity.
Obviously, the method described above may be suitable for obtaining numerous other items of information.
In particular, it may be suitable for determining whether a sensor arranged on the luminal or abluminal surface of the stent or, more generally, on a surface of an implantable medical device, particularly on a surface of the implantable medical device in contact with a wall of the cavity wherein the medical device is implanted or on a surface of the implantable medical device intended to be in contact with the blood, is optionally coated with endothelial or smooth muscle tissue.
It may also be suitable for determining the composition of the tissue coating the sensors distributed on the implantable medical device (particularly on the luminal surface or on the abluminal surface of a stent) for example by Electrical Impedance Spectroscopy (EIS), particularly by applying currents of separate frequencies in the measurement circuit.
The electrical circuit 10A in
The electrical circuit 10A firstly includes an analogue/digital converter 80 situated between the electrical measurement circuit 16 and the variable impedance 15 connected to the antenna 18 in the emitting circuit. This analogue/digital converter 80, which may also be used in the electrical circuit 10 in
Moreover, the electrical circuit 10A is distinguished from that in
The same applies for the electrical circuit 200A illustrated by
It should be noted herein that the presence of the elements 60A of known and fixed impedance and of the analogue/digital converter 80 are independent. Embodiments may be envisaged not involving one of the two among the analogue/digital converter 80 and the elements 60A of known impedance.
In
In the example shown, an analogue/digital converter 80 is also provided between the parallel branches formed by the measurement lines 90 and the variable impedance 15.
The electrical circuit 10C illustrated in
It should be noted that it is also possible to envisage electrical circuits with a plurality of measurement lines 90 on the basis of the electrical circuits 100 and 200 in
It is also possible to envisage elements 60A of known and fixed impedance between each of the sensors on each of these lines or on certain lines only. It is then possible to identify the line wherein the measurement is made at each time by choosing unique combinations of impedances 60 at the start of the line 90 for each line 90.
In the scenario where the electrical circuit 10B, 10C includes a plurality of measurement lines, it has been determined that it is particularly advantageous that the measurement lines extend on the medical device 12, particularly on the stent 12 in imbricated coaxial helices. In other words, the measurement lines extends in parallel along helices wound around one another. Indeed, this makes it possible to minimise the distance between sensors of different lines. This is particularly advantageous because if a sensor 22 of a line 90, or even the entire line 90 is defective, the missing value(s) may be better approximated by the values measured with the other measurement line(s), of which one or a plurality of sensors are situated in the vicinity. The device 12 thereby gains in robustness, which is particularly advantageous when it is implanted in a patient's body.
It should be noted that the electrical circuits described are suitable for determining for each sensor of the electrical circuits, the value measured thereby. The position of the sensors on the medical device, particularly on the stent, being known, it is possible to determine a model representing in real time, the progression of the physical parameters measured on the medical device. As such, a practitioner may obtain real-time information. This information may particularly relate to the correct positioning of the medical device, particularly of the stent, in a cavity of the human body. Representing the pressures measured by pressure sensors arranged on the outer surface of the medical device, particularly of the stent, can enable the practitioner to determine whether this medical device is correctly implanted or not: a measured pressure that is too low, for example, may indicate that the stent is not in contact with the wall of the cavity receiving same.
The processing unit of the medical system described above, comprising for example an electronic control unit and a screen, or a computer, may be suitable for determining a real-time model, for example a 3D model, based on the values measured and displaying the model on the screen. The values between the measurement points may, in this case, be approximated, particularly by convolution according to the distance to the closest measurement points.
Various visual and/or acoustic signals may be emitted by the processing unit, in the scenario where at least one measured value does not meet expectations. The visual signals may particularly be suitable for identifying on the model shown, the sensors 22 for which the measured values are not conforming.
Alternatively, the processing unit may process the digital values measured, compare them to expected value ranges and display as an output in a different manner, the points where the measurement is within the ranges and the points where the measurement is not within the ranges, for example by using different display colours.
The visual signals complete the display of the model described above.
The invention is not restricted solely to the examples of embodiments described above with regard to the figures, by way of illustrative and non-restrictive examples.
In particular, the implantable medical device may be chosen from the group comprising:
Alternatively, the medical device may not be implantable. It can then, in particular, be applied on a part of the human body. The medical device may in this case take the form of a dressing, bandage or strip to be applied onto a patient's skin. The medical device may also take the form of a contact lens to be placed on a patient's cornea.
Finally, according to a further alternative embodiment, the medical device may be neither implantable in the human body, not applicable thereon.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1653032 | Apr 2016 | FR | national |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 16091766 | Oct 2018 | US |
| Child | 17990406 | US |
