WO2024069106A1 - Medical endoscopic system with electromagnetic wave insensitivity - Google Patents

Abstract

The invention relates to an endoscopic system comprising: - an insertion tube (2) having a distal part equipped with a distal head (4) comprising at least one sensor (5) of a physical variable delivering an electrical measurement signal; - at least one flexible printed circuit (11) extending inside the insertion tube (2) and providing the electrical connection between the sensor (5) and electrical components (Ta). The insertion tube (2) comprises an electromagnetic shield (13) surrounding the flexible printed circuit (11) and configured to reduce the electromagnetic disturbances that may be applied to the electrical measurement signal delivered by the sensor.

Description

Description

Title of the invention: Medical endoscopic system exhibiting insensitivity to electromagnetic waves

Technical area

[0001] The present invention relates to the technical field of medical endoscopic systems in the general sense allowing access to the interior of a body such as a cavity or a canal for example and it aims more precisely as medical endoscopic systems, medical catheters and medical endoscopes.

[0002] The medical endoscopic system implemented in the context of the present invention finds particularly advantageous applications for allowing access to the internal surface of a hollow organ, a cavity or a natural or artificial conduit of the human body with a view to carrying out various operations for therapeutic, surgical or diagnostic purposes, and which can be used in the field of the urinary tract, the gastrointestinal tract, the respiratory system, the cardiovascular system, the trachea, the sinus cavity, the female reproductive system, the abdominal cavity or any other part of the human body to be explored by a natural or artificial means.

Prior art

[0003] Conventionally, a medical endoscopic system of the medical catheter or medical endoscope type comprises a control handle to which is fixed an insertion tube having, opposite its part fixed to the control handle, a distal head. This insertion tube has a greater or lesser length and flexibility so that it can be introduced into a natural or artificial access route in order to perform various operations or functions for therapeutic, surgical or diagnostic purposes. It should be noted that such an endoscopic system is designed to have the smallest possible section in order to be able to access access routes having a limited passage section. [0004] For a medical endoscopic system of the endoscope type, the distal head is equipped in particular with a vision system making it possible to examine the organ, the cavity or the conduit of the human body. Upstream of this distal head, the insertion tube comprises a flexion structure or crutching part formed of articulated vertebrae allowing the orientation of the distal head. This medical endoscope is intended to be connected to a medical electronic device comprising a unit for processing the image signals delivered by the vision system of the endoscope.

[0005] The vision system mounted at the distal part of the tube comprises a camera associated or not with one or more light sources such as light-emitting diodes. The camera, or even the light sources, are electrically connected to electrical components located in the handle or in the medical device. According to the exemplary embodiment described by patent application US 2022/0160218, the camera and the light sources located at the distal part of the insertion tube are connected to the electrical components located in the handle, via a flexible printed circuit extending inside the working channel.

[0006] This patent application specifies that this flexible printed circuit is small enough to leave room for a working tool and the fluids inside the working channel. However, the presence of this flexible printed circuit inside the working channel is a source of difficulties for handling the work tools. Additionally, this patent application indicates that the flexible printed circuit provides reliable electrical communications between the distal head and the proximal region of the endoscopic device. Indeed, there appears to be a need to have a signal with the highest possible quality for the electrical signal delivered by the camera. However, the use of a flexible printed circuit is not sufficient to guarantee a good quality electrical signal.

Presentation of the invention

[0007] The object of the invention is to remedy the drawbacks of the state of the art by proposing an endoscopic system having a limited passage section while ensuring that the electrical measurement signal coming from the distal head is of high quality to obtain optimized image quality and a better signal-to-noise ratio.

Another object of the invention is to propose an endoscopic system delivering an electrical measurement signal insensitive to electromagnetic disturbances.

[0009] To achieve such objectives, the endoscopic system comprises:

- an insertion tube having a proximal part connected to a control handle and a distal part equipped with a distal head comprising at least one sensor of a physical quantity delivering an electrical measurement signal;

- at least one flexible printed circuit extending inside the insertion tube and ensuring the electrical connection between the sensor and electrical components,

- the insertion tube comprising an electromagnetic shield surrounding the flexible printed circuit and configured to reduce the electromagnetic disturbances likely to be applied to the electrical measurement signal delivered by the sensor.

[0010] According to an advantageous implementation characteristic, the electromagnetic shielding is connected to a ground terminal.

[0011] According to a preferred embodiment, the electromagnetic shielding comprises a latticework of an electrical conductor extending over the length of the insertion tube.

Advantageously, the electromagnetic shielding comprises a latticework of an electrical conductor embedded in a thermoplastic resin.

Preferably, the trellis has a number of crossings per surface unit (inch) of between 2 and 100.

[0014] According to a preferred example of implementation, the insertion tube surrounds a tubular conduit forming an operating channel, at least one flexible printed circuit being positioned outside the tubular conduit. [0015] According to another example of implementation, the insertion tube surrounds a tubular conduit forming an operating channel, two flexible printed circuits being positioned outside the tubular conduit.

[0016] According to one characteristic of the invention, at least one flexible printed circuit comprises at its distal end, from a fold, a folded fixing part for a sensor.

[0017] For example, the folded fixing part for the sensor extends substantially at 90° relative to the rest of the flexible printed circuit.

The flexible printed circuit has a first face on which electrical connection tracks are provided between the electrical components and the sensor.

The flexible printed circuit has a first face and a second face opposite the first on which is arranged at least one electrical connection track connected to ground.

[0020]Advantageously, the flexible printed circuit has a first face and a second face opposite the first on which is arranged at least one electrical connection track connected to ground.

Brief description of the drawings

[0021] [Fig. 1] Figure 1 is a schematic general view of an endoscopic system of the catheter or endoscope type in the general sense.

[0022] [Fig. 2] Figure 2 is a partial view of an exemplary embodiment of an insertion tube forming part of an endoscopic system from which the control handle is removed.

[0023] [Fig. 3] Figure 3 is a longitudinal sectional view taken substantially along the lines A-A of Figure 2.

[0024] [Fig. 4] Figure 4 is a cross-sectional view taken substantially along the lines AA of Figure 3. [0025] [Fig. 4] Figure 5 is a perspective view of another embodiment of an insertion tube forming part of an endoscopic system from which the control handle is removed.

[0026] [Fig. 6] Figure 6 is a view showing an exemplary embodiment of a distal head of an insertion tube forming part of an endoscopic system according to the invention.

[0027] [Fig. 7] Figure 7 is a longitudinal sectional view taken substantially along the lines A-A of Figure 6.

Description of embodiments

[0028] Fig. 1 illustrates by way of example, a medical endoscopic system 1 of the endoscope or catheter type 1 in the general sense designed to access the interior of a body such as a cavity or a canal for example. Conventionally, an endoscopic system 1 of the endoscope or catheter type comprises an insertion tube 2 having on one side, a proximal part 2i connected to a control handle 3 and on the opposite side, a distal part 2 ₂ , which is equipped with a distal head 4. The insertion tube 2 is fixed temporarily or permanently on the control handle 3. In the example illustrated (figures 2 and 3), the proximal part 2i of the insertion tube is engaged in a housing of a tip 3a intended to be fixed to the distal part of the handle 3. This insertion tube 2 which has a more or less significant length and flexibility is intended to be introduced into an access route natural or artificial to perform various operations or functions for therapeutic, surgical or diagnostic purposes.

The insertion tube 2 is made of a semi-rigid material such as, for example, thermoplastic elastomer (TPE). The insertion tube 2 has a length adapted to the length of the conduit to be inspected and which can be between 5 cm and 2 m. The insertion tube 2 has various cross-section shapes such as square, oval or circular. This insertion tube 2 which is in contact with tissues, human organs or medical equipment (trocars or probes), is essentially for single use or multiple of a patient or even for reusable use after decontamination, disinfection or sterilization. In accordance with the invention, the insertion tube 2 is provided with shielding to ensure electromagnetic protection, as will be explained in detail later in the description.

Generally speaking, the distal head 4 of the medical endoscopic system 1 is made in the form of a support allowing the mounting of at least one sensor 5 of a physical quantity delivering an electrical measurement signal. As emerges more precisely from Figures 6 and 7, it should be understood that the distal head 4 is provided with a sensor 5 of the type adapted to the function of the medical endoscopic system 1. In the preferred example of embodiment illustrated in the continuation of the description for which the endoscopic system 1 is an endoscope then the sensor 5 of a physical quantity is a camera. In the case where the endoscopic system 1 is a catheter, its distal head 4 can be provided as sensor 5, with a pressure sensor or an ultrasonic sensor. It should be noted that the sensor may be sensitive to ultrasound, magnetic fields or electromagnetic waves visible to the human eye or invisible such as, for example, X-rays, infrared rays or radio waves. Indeed, the endoscopic system 1 is generally used in an environment in which various electrical equipment such as electric scalpels, X-ray radiography devices, scanners or screens operate, likely to affect the operation of the sensor of the distal head 4.

The sensor 5 is mounted in any appropriate manner in the distal head 4. For example, in the case where the sensor 5 is a camera, the sensor 5 is mounted inside a cavity 4a of the distal head 4 opening through its sensitive surface 5a, into the transverse end face 4b of the distal head 4. The sensor 5 is fixed in the cavity 4a by a resin.

[0032] The sensor 5 fitted to the distal head 4 thus delivers a measurement signal intended to be processed by a processing unit T located in the control handle 3 as illustrated in Figure 5 and/or in a medical electronic device connected to the control handle 3. This processing unit T thus comprises electrical components Ta mounted in the example illustrated, on a printed circuit board Tb fixed inside the control handle 3. Of course, the electrical components Ta for processing the measurement signal can be located in the control handle 3 and/or outside the handle control 3, such as for example in a medical electronic device (such as an electronic tablet) connected to the control handle by a connection cable.

[0033] According to a preferred embodiment, the endoscopic system 1 according to the invention is an endoscope comprising a vision system capable of bringing back an image of the distal part of the insertion tube 2. The endoscopic system 1 thus comprises a vision system penetrating inside the insertion tube 2 up to the distal head 4. The vision system is capable of bringing back an image of the distal part of the insertion tube 2. Conventionally, the vision system vision comprises as sensor 5, a CMOS type camera or a camera known under the trade name CameraCubeChip. Preferably, the vision system also includes one or more light sources not shown such as light-emitting diodes to illuminate the area to be viewed.

[0034] According to a preferred embodiment, the endoscopic system 1 also comprises, inside the insertion tube 2, a tubular conduit 6 forming an operating or working channel extending from the control handle 3 to 'to the distal head 4 to allow at the level of this distal head, the supply of various tools and/or fluids and/or the suction of fluids (Figure 3). As appears more precisely from Figure 4, the tubular conduit 6 is therefore surrounded by the insertion tube 2 leaving a limited space 7 between them. It should be noted that the tubular conduit 6 is surrounded by the tube d insertion 2 over its entire length between the distal head 4 and the tip 3a. Conventionally, the tubular conduit 6 extends beyond the end piece 3a inside the control handle 3.

[0035] According to the preferred embodiment, the endoscopic system 1 also includes a control mechanism 8 making it possible to orient the distal head 4 relative to the longitudinal axis L of the insertion tube 2. For this purpose, the tube insertion tube 2 comprises upstream of the distal head 4, a flexion, folding or tilting structure 9 allowing the orientation of the distal head 4 relative to the longitudinal axis L of the insertion tube 2. The mechanism control 8 can be made in any appropriate manner so that the distal head 4 can be moved between a rest position in which the insertion tube 2 is straight and a crutched position in which the crutching part 9 is curved. For example, the control mechanism 8 may include a manual control lever 8a rotating a pulley 8b on which is fixed at least one actuation cable 8c mounted inside the space 7 to be fixed at the level of the distal head 4.

[0036] According to a characteristic of the invention, the endoscopic system 1 comprises at least one flexible printed circuit 11 extending inside the insertion tube 2 and ensuring the electrical connection between the sensor 5 and the electrical components Ta . Conventionally, each flexible printed circuit 11 comprises a flat flexible support provided with electrical connection tracks 12 and on which the sensor 5 is mounted by all appropriate techniques. Each flexible printed circuit 11 has a first face lia and a second face 11b opposite the first face lia. For example, the flexible printed circuit 11 comprises a first face lia on which electrical connection tracks 12 are provided between the electrical components Ta and the sensor 5. According to another alternative embodiment, electrical connection tracks 12 are provided on the first face lia and at least one electrical connection track connected to ground is provided on the second face 11b. Advantageously, an electrical connection track connected to ground is provided over the entire surface of the second face 11b of the flexible printed circuit 11.

[0037] In the example illustrated, the endoscopic system 1 comprises a flexible printed circuit 11 extending inside the insertion tube 2 ensuring the electrical connection between the sensor 5 and the electrical components Ta mounted on the inside the control handle. The flexible printed circuit 11 is thus present in the form of a narrow strip with a width of between 0.5 mm and 2.5 mm and a thickness of between 0.05 mm and 0.8 mm.

[0038] Advantageously, the flexible printed circuit 11 is coated on these two faces with a protective varnish also ensuring electrical insulation.

According to another embodiment not shown, the endoscopic system 1 comprises two flexible printed circuits 11 ensuring the electrical connection between the sensor 5 and the electrical components Ta. This exemplary embodiment increases the possibilities of controlling the flexibility of the insertion tube 2 and of choosing the positioning of the flexible printed circuits 11 inside the insertion tube 2.

[0040] According to an advantageous embodiment feature, the flexible printed circuit(s) 11 are positioned outside the tubular conduit 6. Advantageously, the flexible printed circuit(s) 11 are positioned in the space 7 delimited between the insertion tube 2. and the tubular conduit 6 (Figure 4). The flexible printed circuit(s) 11 extend parallel to the longitudinal axis of the insertion tube 2 or are more or less wound around the tubular conduit 6.

Advantageously, the flexible printed circuit 11 is configured so as to be able to present a fold 11c to have a folded part lld. Typically, the flexible printed circuit 11 is made of polyimide. Thus, the flexible printed circuit 11 comprises at its distal end, from the fold 11c, a folded part lld adapted to allow the fixing of the sensor 5 such as the camera. For example, the folded part lld extends substantially at 90° relative to the rest of the flexible printed circuit 11 which extends substantially parallel to the longitudinal axis of the insertion tube 2. Thus, the sensor 5 has a sensitive face 5a located in the cross section of the distal head considering that the fixing terminals of the sensor 5 on the flexible printed circuit 11 are located opposite the sensitive face of the sensor.

The conductive tracks 12 of the flexible printed circuit 11 are connected in any appropriate manner to the electrical components Ta. In the embodiment example illustrated in Figure 5, the flexible printed circuit 11 comprises at its proximal end, a connection part linked with an electrical connector Ce fixed on the printed circuit board Tb.

[0043] According to a characteristic of the invention, the insertion tube 2 comprises an electromagnetic shield 13 surrounding the flexible printed circuit 11 and configured to reduce the electromagnetic disturbances likely to be applied to the electrical measurement signal delivered by the sensor 5 Thus, the electromagnetic shielding 13 of the insertion tube 2 aims to reduce the electromagnetic field in the vicinity of the flexible printed circuit 11 by interposing a barrier between the source of the field and the flexible printed circuit 11.

The electromagnetic shielding 13 is produced using an electrically conductive material and in all appropriate ways. The insertion tube 2 thus comprises a metal envelope arranged in the form of a tube, a braid, a mesh or a ribbon, configured to ensure electromagnetic protection with respect to the flexible printed circuit 11. It should be noted that the metal envelope is part of the insertion tube 2 without opening onto the external surface of the insertion tube 2. The metal envelope is thus advantageously embedded in the insertion tube 2. However, the metal envelope can open in whole or in part onto the internal surface of the insertion tube 2.

[0045] Typically, the electromagnetic shielding 13 is configured to suppress electromagnetic disturbances in a range between 80 MHz and 5 GHz.

[0046] According to a preferred embodiment, the electromagnetic shielding 13 comprises a mesh of an electrical conductor extending over the length of the insertion tube 2 and preferably over the entire length of the insertion tube 2 (Figure 5 ). The mesh is made from one or more wires, for example stainless steel, copper, silver, carbon or other electrically conductive material. This wire preferably has a round or even ovoid section but can also be of square or rectangular section. Preferably, the diameter of the wire is between 0.01 and 0.3 mm. Conventionally, the trellis is formed by an intersection of electrical conductive wires. According to an advantageous embodiment, the trellis comprises a number of crossings of conductive wires per surface unit (inch) of between 2 and 100. [0048] According to an exemplary embodiment, the electromagnetic shielding 13 comprises a trellis of a conductor electrical embedded in a thermoplastic resin to form the insertion tube 2. Advantageously, the electromagnetic shielding 13 is connected to a ground terminal Bm equipping the printed circuit board Tb.

Claims

Claims [Claim 1] Endoscopic system comprising: - an insertion tube (2) having a proximal part connected to a control handle (3) and a distal part equipped with a distal head (4) comprising at least one sensor (5) of a physical quantity delivering a electrical measurement signal; - at least one flexible printed circuit (11) extending inside the insertion tube (2) and ensuring the electrical connection between the sensor (5) and electrical components (Ta), - characterized in that the insertion tube (2) comprises an electromagnetic shield (13) surrounding the flexible printed circuit (11) and configured to reduce the electromagnetic disturbances likely to be applied to the electrical measurement signal delivered by the sensor. [Claim 2] Endoscopic system according to claim 1 wherein the electromagnetic shield (13) is connected to a ground terminal. [Claim 3] Endoscopic system according to one of the preceding claims according to which the electromagnetic shielding (13) comprises a mesh of an electrical conductor extending over the length of the insertion tube. [Claim 4] Endoscopic system according to one of the preceding claims according to which the electromagnetic shielding (13) comprises a mesh of an electrical conductor embedded in a thermoplastic resin. [Claim 5] Endoscopic system according to one of claims 3 or 4 according to which the mesh has a number of crossings per surface unit (inch) of between 2 and 100. [Claim 6] Endoscopic system according to the preceding claim according to which the insertion tube (2) surrounds a tubular conduit (6) forming an operating channel, at least one flexible printed circuit being positioned outside the tubular conduit (6). [Claim 7] Endoscopic system according to one of the preceding claims according to which the insertion tube (2) surrounds a tubular conduit (6) forming an operating channel, two flexible printed circuits (11) being positioned outside the tubular conduit ( 6). [Claim 8] Endoscopic system according to one of the preceding claims according to which at least one flexible printed circuit (11) comprises at its distal end, from a fold (11c), a folded part (lld) for fixing a sensor (5). [Claim 9] Endoscopic system according to the preceding claim according to which the folded part (lld) for fixing the sensor (5) extends substantially at 90° relative to the rest of the flexible printed circuit (11). [Claim 10] Endoscopic system according to one of the preceding claims according to which the flexible printed circuit (11) comprises a first face (lia) on which electrical connection tracks (12) are provided between the electrical components (Ta) and the sensor (5). [Claim 11] Endoscopic system according to one of the preceding claims according to which the flexible printed circuit (11) comprises a first face (11a) and a second face (11b) opposite the first on which is arranged at least one connection track electrical connected to ground. [Claim 12] Endoscopic system according to one of the preceding claims according to which the flexible printed circuit (11) comprises at its proximal end, a connection part (link) with a connector (Ce).