Bendable tube with path length compensation for steering wire

Abstract

A deflectable tube (312) has a deflectable tip section (301) and a bendable body section (309). The deflectable tube has one or more turning wires (16 (i)) that rotate helically in the body section (309) in order to compensate for path length differences occurring in the body section (309) when the body section (309) is bent. In order to isolate axial loads in the body section (309), the deflectable tube (312) is provided with one or more longitudinal force isolation elements (322 (k)) in the body section (309), the one or more longitudinal force isolation elements extending parallel to the one or more steering wires (16 (i)). Both ends of the force isolation element (322 (k)) are attached to the outer tube (340) or the inner tube (330) or both.

Description

Technical Field

[0001] This invention relates to a bendable tube with path length compensation and a steering wire. It also relates to a bendable tube with an improved elastic hinge. Furthermore, it relates to an invasive instrument, such as an endoscope comprising this bendable tube. Background Technology

[0002] The transformation from surgical interventions requiring large incisions to expose the target area to minimally invasive surgical interventions—that is, interventions requiring only natural openings or small incisions to establish access to the target area—is a well-known and ongoing process. In minimally invasive surgical interventions, the operator (e.g., a physician) needs an access device positioned to introduce and guide invasive instruments into the human or animal body through an access port. To reduce scarring and pain in human or animal patients, the access port is preferably provided through a single small incision in the skin and underlying tissues. In some applications, natural openings in the body can serve as the entry point. Furthermore, the access device preferably allows the operator to control one or more degrees of freedom provided by the invasive instruments. In this way, the operator can perform the desired movements at the target area within the human or animal body in an ergonomic and precise manner, while reducing the risk of injury to the instruments used.

[0003] Surgical invasive instruments and endoscopes are well known in the art. Both invasive instruments and endoscopes can include a steerable tube to enhance their guidance and steering capabilities. Such a steerable tube may include a proximal portion, a distal portion, and an intermediate portion, the proximal portion including at least one flexible region, the distal portion including at least one flexible region, wherein the steerable tube further includes a steering arrangement adapted to convert deflection of at least a portion of the proximal portion relative to the intermediate portion into a corresponding deflection of at least a portion of the distal portion. Alternatively, the distal flexible region can be steered by a robotic system arranged at the proximal end of the steerable instrument.

[0004] A steerable invasive instrument may include a handle disposed at the proximal portion of a steerable tube for steering the tube and / or for steering a tool disposed at the distal portion of the steerable tube. Such a tool may be, for example, a camera, a manual manipulator (e.g., scissors, tweezers), or a manipulator that uses an energy source (e.g., electrical, ultrasonic, or light energy).

[0005] Furthermore, such a steerable tube may include multiple coaxially arranged cylindrical elements, including an outer cylindrical element, an inner cylindrical element, and one or more intermediate cylindrical elements, depending on the number of flexible regions in the proximal and distal portions of the tube, and the desired implementation of the steering components of the steering arrangement. That is, all steering components may be arranged in a single intermediate cylindrical element, or the steering components may be divided into different groups, with each group of steering components at least partially arranged in different or the same intermediate cylindrical elements. In most prior art devices, the steering arrangement includes a conventional steering cable with a diameter, for example, less than 1 mm, as the steering component, wherein the steering cable is arranged between the relevant flexible regions at the proximal and distal portions of the tube. Other steering units, such as spherical steering units or robot-driven steering units, may be alternatively applied at the proximal end.

[0006] However, due to the many well-known drawbacks of steering cables, for some applications it may be desirable to avoid steering cables and implement steering components instead using one or more sets of steering wires that form an integral part of the one or more intermediate cylindrical elements. Each intermediate cylindrical element, including the steering wires, can be manufactured by using suitable material addition techniques (such as injection molding or plating) or by starting with the tube and then using suitable material removal techniques (such as laser cutting, photochemical etching, deep pressing, conventional chipping techniques (such as drilling or milling), or high-pressure waterjet cutting systems). The steering wires manufactured in this way are then implemented as longitudinal strips produced from the tube and can be used as wire drawing / pushing. Among the aforementioned material removal techniques, laser cutting is highly advantageous because it allows for very accurate and clean material removal under reasonable economic conditions.

[0007] The internal and external cylindrical elements can also be manufactured from tubes. These tubes should be flexible at the bendable locations at the distal end (and possibly the proximal end) of the instrument. Furthermore, the internal and external cylindrical elements should also be flexible at other locations where the instrument should be flexible. This can be achieved by providing hinges for the internal and external cylindrical elements at these flexible locations. Such hinges can be produced by cutting a predetermined pattern in the tube (using a laser). Many different patterns are known from the prior art. The choice of pattern depends on the design requirements at the relevant locations, including but not limited to the required bending angle, bending flexibility, longitudinal stiffness, and radial stiffness.

[0008] As is known from flexible endoscopic instruments, such as those with steerable tips, flexible invasive steerable instruments can exhibit performance defects regarding control of the steerable tip. When such a flexible instrument is inserted into the body through a curved channel (endoscope or natural body cavity), the bending of the instrument causes displacement of the longitudinal tip steering element. Since in conventionally constructed instruments, the steering element (e.g., a wire) is fixed proximally to the steering mechanism (e.g., a handle) and distally to the steerable tip, movement of the steering wire will result in deflection of the steering mechanism and / or deflection of the steerable tip. This leads to the following problems: when the instrument is advanced through a narrow curved channel, and when the steering mechanism is held in a fixed position, the tip deflects uncontrollably during advancement and may become stuck, for example, in a narrow endoscopic working channel, or it may damage tissue in a soft tissue natural body cavity, such as the lungs, bronchi, or esophagus.

[0009] Another problem is that when the instrument passes through the inlet channel and the instrument tip reaches the target surgical site, the tip deflection no longer matches the deflection of the steering mechanism. Therefore, the neutral position of the steering mechanism does not correspond to the neutral position of the steerable tip. This deviation can indeed adversely affect the user's eye-hand coordination.

[0010] Another problem with flexible, steerable instruments is that when the tip is steered using a steering element, the steering element also steers the body, as the entire body mechanically behaves like the steerable tip. The deflection ratio between the body and tip deflection depends solely on the bending stiffness of the body and tip. The stiffer the body is relative to the tip, the more the tip will be steered. In practice, the tip is more flexible than the body, but there is still a tendency to steer the tip, which in turn will generate lateral forces in the surrounding channels that tend to hold the instrument body at a certain curvature. If soft body tissue is present in the surrounding channels, this is highly undesirable instrument behavior, as the lateral forces can damage the surrounding tissue. Furthermore, body movement can interfere with the positioning of the steerable tip at the target site and make accurate and predictable tip steering more difficult.

[0011] This problem arises because different steering wires within the flexible body of the instrument acquire varying lengths due to bending. Therefore, reference... Figure 1A and Figure 1B Let me explain.

[0012] Figure 1A The body of a tubular device 1 is shown, having a first steering wire 16(1) extending in a straight line from one end to the opposite end on one side of the body, and a second steering wire 16(2) extending in a straight line from one end to the opposite end (i.e., at a position rotated 180 degrees) on the other side of the body. The steering wires extend parallel to each other. The tube 1 has a central axis of symmetry 29. The body of the tube 1 has a length L. Figure 1A In its unbent state, the steering wires 16(1) and 16(2) also have a length L inside the body.

[0013] Figure 1B The tube 1 is shown in a bent position, here a 180-degree curve. In this case, the length of the axis 29 inside the body remains the same. However, a portion of the steering wire 16(1) located inside the curve now extends from the body by an offset of +ΔL, while a portion of the steering wire 16(2) located outside the curve now extends from the body by an offset of -ΔL. In other words, the steering wire 16(1) is pushed outside the body, and the steering wire 16(2) is pulled inside the body. Since the steering wires 16(1), 16(2) are attached to the end of the instrument, this causes one or more of the problems mentioned above, such as undesirable deflection of the end.

[0014] As is known from the prior art, this undesirable effect can be compensated for by rotating the steering wires 16(1), 16(2) 180 degrees around the body spiral, such as Figure 2A As illustrated in the diagram. Figure 2A In the process, the 180-degree rotation of the steering threads 16(1) and 16(2) is performed in the central section of the body. When Figure 2A The body is like Figure 2B When the curve shown is bent 180 degrees, half of the length of each of the steering wires 16(1) and 16(2) is located inside the bending body, and the other half is located outside the bending body. Therefore, with Figure 2A Compared to the previous case, both have a smaller portion of length on the inside of the bent body and a longer portion of length on the outside of the bent body, thus compensating for the difference in path length caused by the bending of the body.

[0015] A method based on is known from US 4,745,908. Figure 2B The patent describes an invasive device with a deflectable tip, based on existing technological solutions. Deflection is caused by a cable located within a catheter. Both the cable and the catheter extend from the proximal end to the distal end. The catheter's path is helically coiled around a central longitudinal axis.

[0016] Because the catheter has a substantially constant total length due to the non-straight catheter path, the cable length and catheter length remain relatively equal even when the instrument's axis is bent or located in a bent channel path and twisted or turned to rotate the lens portion. Because the cable length and catheter length remain relatively equal, there is no involuntary or uncontrolled deflection of the distal end of the instrument.

[0017] This known technology is sometimes referred to as Bowden cable technology. Another term used in the art is “coiled conduit”. Other prior art can be found, for example, in US 20110004157 A1, US 20080300462 A1, WO 2009048796A2, KR 101312071 B1, WO 2015084174, WO 2016063348 A1, US 2018055589 A1, WO2020016577 A1, and WO 2022260518. Summary of the Invention

[0018] In a first aspect, the object of the present invention is to provide a steerable device for endoscopic and / or invasive applications, wherein at least one of the aforementioned problems is resolved or at least reduced.

[0019] This is achieved by a steerable device as described in the appended independent claim 1.

[0020] Force isolation elements isolate the axial loads of the invasive instrument from the bendable body portion, loads caused by pulling / pushing a steering wire to deflect the deflectable end portion. Because the steering wire helically rotates in at least a portion of the body section, it can compensate for at least some path length difference when the body section bends. Furthermore, because the longitudinal force isolation elements extend through the body portion parallel to the steering wire, they also helically rotate, thus also providing at least some path length compensation for the longitudinal force isolation elements themselves within the body portion.

[0021] An embodiment of the first aspect of the invention is claimed in the claims dependent on claim 1.

[0022] In a second aspect, the present invention relates to an improved hinge structure as described in independent claim 17.

[0023] An embodiment of the second aspect of the invention is claimed in the claims dependent on claim 17. Attached Figure Description

[0024] Further features and advantages of the invention will become clear from the description of the invention through non-limiting and non-exclusive embodiments. These embodiments should not be construed as limiting the scope of protection. Those skilled in the art will recognize that other alternatives and equivalent embodiments of the invention can be conceived and practiced without departing from the scope of the invention. Furthermore, individual features of different embodiments can be combined even if not explicitly shown in the drawings or explained in the description, unless such combination is physically impossible. The scope of the invention is limited only by the claims and their technical equivalents. Embodiments of the invention will be described with reference to various figures in these drawings, in which the same or identical reference numerals denote the same, identical, or corresponding parts, and in the drawings:

[0025] Figure 1A and Figure 1B A schematic diagram is shown to illustrate some of the problems addressed in the first aspect of the invention.

[0026] Figure 2A and Figure 2B Showing the target Figure 1A , Figure 1B An illustrative solution to the problem shown in the prior art.

[0027] Figure 3A and Figure 3B The prior art tube shows a steering device with a steering wire made of the tube wall.

[0028] Figure 4 A schematic perspective view of a tube with a deflection wire made of the tube wall is shown.

[0029] Figure 5A A schematic perspective view of an alternative tube with a steering wire made of the tube wall is shown.

[0030] Figure 5B It shows Figure 5A An enlarged view of the distal portion of the tube shown.

[0031] Figure 5C A schematic cross-sectional view of some components of the proximal portion of the steerable device is shown.

[0032] Figures 5D to 5F An embodiment of a force isolation element is shown.

[0033] Figure 5G A prior art embodiment of a tube with deflecting wires is shown, which are separated by spacer wires extending from the proximal end to the distal end of the tube.

[0034] Figure 5H An embodiment of a tube with uninterrupted spacer wires is shown.

[0035] Figure 6 It shows that it can be used Figure 4 , Figure 5A , Figure 5B and Figure 5C An example of an inner tube used inside a pipe is shown.

[0036] Figure 7 It shows that it can be used Figure 4 , Figure 5A , Figure 5B and Figure 5C Examples of the ends and body portions of the outer tube used outside the pipe are shown.

[0037] Figure 8 A hinge structure based on the prior art is shown.

[0038] Figures 9 to 12C A portion of an embodiment of a hinge structure according to a second aspect of the invention is shown. Detailed Implementation

[0039] In embodiments, the invention is implemented as a tube having a suitable cutting pattern, hereinafter also referred to as a "cylindrical element". The basic technology of such tubes is described, for example, in EP 2 273 911 B1. Figure 3A An exploded view of three cylindrical members forming the device according to EP 2 273911 B1 is shown. The device 202 consists of three coaxial cylindrical members: an inner member 204, an intermediate member 206, and an outer member 208. The inner cylindrical member 204 is composed of a first rigid steerable end portion 210, a first flexible portion 212, an intermediate rigid portion 214, a second flexible portion 216, and a second steerable rigid end portion 218. The first rigid steerable end portion is typically used in operating locations that may be difficult to reach, for example, inside the human body. The steerable end portion 210 is located at the distal end of the device. The steerable rigid end portion is located at the proximal end of the device.

[0040] The outer cylindrical member 208 is constructed in the same manner of a first steerable rigid portion 201, a flexible portion 203, an intermediate rigid portion 205, a second flexible portion 207, and a second steerable rigid portion 209. The flexible portions of the cylindrical members 204 and 208 are also referred to in the art as "hinges". The different portions of the cylindrical members 208 and 212 are substantially the same length, such that when the cylindrical member 204 is inserted into the cylindrical member 208, the steerable end portions 210 and 201, the flexible portions 212 and 203, the rigid portions 214 and 205, the flexible portions 216 and 207, and the rigid steerable end portions 218 and 209 are aligned with each other.

[0041] The intermediate column member 206 also has a first steerable rigid end portion 240 and a second steerable rigid end portion 242, which are located in the assembled state between the corresponding rigid steerable end portions 210 and 201 and the rigid steerable end portions 218 and 209 of the other two column members 204 and 208, respectively.

[0042] The portions of components 216, 218, 242, 207, 209, and 211 that are axially aligned with components 216 and 207 together form a steering unit 244 of the steerable device. The portions of components 210, 212, 240, 201, 203, and 211 that are axially aligned with components 212 and 203 together form a steerable or deflectable portion 248 of the steerable device. The portion between the steering unit 244 and the steerable portion 248 is the body portion 246.

[0043] The intermediate columnar member 206 has an intermediate portion 211 formed by one or more, for example, three separate longitudinal elements 16(i) (i = 1, 2, ..., I), which may have different forms and shapes. These longitudinal elements are made of the wall material of the intermediate columnar member 206 and thus have the form of longitudinal strips. Since they act as steering wires, they will be referred to as "steering wires" below. After assembling the three columnar members (where columnar member 204 is located inside columnar member 206 and two combined columnar members 204, 206 are located inside columnar member 208), the rigid steering end portions 218, 242, 209 of the three columnar members can be attached to each other. In addition, the steerable end portions 210, 240, 201 can be attached to each other. The steering end portions 218, 242, 209 are located at the proximal end of the invasive instrument, while the steerable end portions 210, 240, 201 are located at the distal end of the invasive instrument.

[0044] All three cylindrical members 204, 206, and 208 are shown extending in a straight line in the axial (or longitudinal) direction. By bending the steering end portions 218, 242, and 209 of the assembled device away from the axial direction, the steering end portions 210, 240, and 201 will also be forced to bend away from the axial direction, as some of the steering wires 16(i) will generate tension while the others will generate thrust, as will be clear to those skilled in the art.

[0045] Figure 3B (Also known from EP 2 273 911 B1) shows Figure 3A An unfolded view of a portion of an alternative embodiment of the intermediate cylindrical component of the device. Figure 3BThe intermediate cylindrical member is formed by a plurality of steering wires 16(i), wherein each steering wire 16(i) is composed of three parts 222, 224 and 226 coexisting with the first flexible part, the intermediate rigid part and the second flexible part, respectively. In the part 224 that overlaps with the intermediate rigid part, each pair of adjacent longitudinal elements 220 are very close to each other in the tangential direction, such that, in fact, there is only a narrow gap between them that is just enough to allow each longitudinal element to move independently.

[0046] In the other two sections 222 and 226, each longitudinal element consists of relatively small and flexible strips 228 and 230 viewed in the circumferential direction, such that there is a significant gap between each pair of adjacent strips, and each strip 228 and 230 is provided with a plurality of cams 232 that extend in the circumferential direction and almost completely bridge the gap to the next strip.

[0047] Figure 3A , Figure 3B The example of the cylindrical element shown can be manufactured entirely by cutting a suitable pattern in the tube (e.g., by laser cutting). Thus, the steering wire 16(i) is a strip made from the wall of the cylindrical element 206.

[0048] They also illustrate the basic techniques used in the cylindrical elements of this invention. Other examples of steerable invasive instruments manufactured by (laser) cutting suitable patterns in cylindrical elements can be found, for example, in WO 2009112060, WO2009127236, WO 2012128618, WO 2012173478, WO 2014011049, WO 2015084174, WO2016089202, WO 2017010883, WO 2017014624, WO 2017082720, WO 2017213491, WO2018067004, WO 2019009710, WO 2020080938, WO 2020214027, WO 2020218920, WO2020218921, WO As obtained in 2022260518, WO 2023287286, and WO 2023287289. Other examples of this may involve devices having more than one steerable end portion and / or having a flexible rather than rigid intermediate portion.

[0049] Path length compensation Figure 4 Implementation shown Figure 3A , Figure 3BAn example of a solution using tube 306. The figure shows the distal portion at the distal end of tube 306. The illustrated embodiment has an annular end portion 300. Proximal to the annular end portion 300, tube 306 has one or more deflecting wires 16(i) (i = 1, 2, ..., I). Here, I = 4, but I can have any other suitable value. The four deflecting wires 16(i) are equidistantly spaced on the circumference of tube 306. All deflecting wires 16(i) are attached to the annular end portion 300, for example, by cutting from the same wall of tube 306 as the annular end portion 300. Note that more deflecting wires or portions thereof may be present in tube 306, for example, some deflecting wires or portions thereof extend to additional deflectable areas at the distal end.

[0050] The distal portion has a deflectable end section 301, which can be deflected by suitable longitudinal movement of the four steering wires 16(i). In the deflectable end section 301, adjacent steering wires 16(i) are separated by spacers 304(i). As seen in the circumferential direction, the spacers 304(i) are located between steering wires 16(i) and 16(i+1). Each spacer 304(i) can be made from the wall of the tube 306 by providing a suitable cutting pattern to the wall material between adjacent steering wires 16(i), such that the resulting spacers 304(i) maintain a desired tangential distance between adjacent steering wires 16(i) while having sufficient flexibility to allow the deflectable end section 301 to deflect. The flexibility depends on the cutting pattern used. The following uses reference numeral 316(i) to explain the possible cutting patterns (see Figure 10). Figure 5B ).

[0051] Proximal to the deflectable end section 301, tube 306 has a body section 309, which has three body sub-sections 303, 305, and 307. In the body sub-section 303 adjacent to the deflectable end section 301, all steering wires 16(i) are straight and extend parallel to each other and parallel to the central axis 29. In the next body sub-section 305 adjacent to body sub-section 303, all steering wires 16(i) are helically rotated 180 degrees around the central axis 29 in a parallel manner. Body sub-section 307 extends proximal to the body sub-section 305. In body sub-section 307, all steering wires 16(i) are straight and extend parallel to each other and parallel to the central axis 29.

[0052] In all sections 301, 303, 305, and 307 of tube 306, all guide wires 16(i) may have equal thickness and width. However, depending on the design, the thickness and / or width of all guide wires 16(i) in each section 301, 303, 305, and 307 may be different, as long as they are flexible along the entire length of the end and body section.

[0053] Spacers 302(i) (i = 1, 2, ..., I) are located between adjacent turning wires 16(i) in the body section 309. Spacers 302(i) are designed to maintain adjacent turning wires at a predetermined distance from each other, while still allowing the body sections 303, 305, and 307 to be bent. Spacers 302(i) can be made from the wall by providing a suitable cutting pattern 310 to the wall of the tube 306.

[0054] The position of the body sub-segment 305, in which the directional wire 16(i) is helically rotated 180 degrees, can be selected based on the application of the tube 306 (i.e., an understanding of the curved channel in which the tube 306 will be inserted). If the body segment 309 is bent due to the insertion of the tube 306 into the curved channel, the difference in path length of the wire 16(i) in the body sub-segments 303, 305, and 307 caused by the bending is compensated for by the helical rotation in the body sub-segment 305, as shown in the reference. Figure 2A , Figure 2B The explanation given.

[0055] Figure 4 The tube 306 shown may have more than one body sub-segment 305 in which the steering wire 16(i) helically rotates 180 degrees. These sub-segments may be continuous with each other or separated by body sub-segments in which the steering wire 16(i) extends straight parallel to the central axis 29 (as in body sub-segment 307). The pitch of the 180-degree helix depends on the application. In an alternative embodiment, the steering wire 16(i) is helical throughout the body segment 309, i.e., there are no body sub-segments 303, 307. To compensate as much as possible for differences in path length between steering wires 16(i) within the body segment 309 due to bending of the body segment, the total helix between the distal and proximal ends of the body segment 309 is an integer multiple of 180 degrees.

[0056] Body section 309 is connected or attached to steering section at its proximal end, the steering section being... Figure 5C The figure is shown by reference numeral 354. This steering section 354 is configured to move the steering wire 16(i) in the longitudinal direction of the instrument, such that the steering wire can together deflect the deflectable end section 301. For this purpose, the steering section 354 may be equipped with a bendable portion configured to convert the bending action into this movement of the steering wire 16(i), as is known in the art, for example... Figure 3A , Figure 3B As shown. Alternatively, the longitudinal movement of the steering wire 16(i) can be controlled by directly controlling the longitudinal movement of the steering wire 16(i) on a single level, for example by means of a robot steering section also known in the art.

[0057] Figure 5A , Figure 5B , Figure 5C , Figure 5D , Figure 6 and Figure 7 An embodiment of the first aspect of the present invention is shown. Figure 5A An inner tube 330 is shown, coaxially surrounded by a central tube 312. An example of the outer tube 340 (its distal end and body section are shown in...) Figure 7 (As shown in the figure) can be arranged coaxially with the inner tube 330 and the intermediate tube 312. Figure 5B An enlarged view of an example of the distal end and body section of the intermediate tube 312 is shown. Figure 5C Some components near the proximal end of the instrument are shown in the cross-sectional view. Figure 6 An enlarged view of an example of the distal end and body section of the inner tube 330 is shown.

[0058] Figure 5A The intermediate tube 312 of the embodiment also has a deflectable end section 301 and a flexible body section 309 proximal to the deflectable end section 301.

[0059] Figure 5A The illustrated embodiment has an annular end portion 314. Proximal to the annular end portion 314, the intermediate tube 312 has one or more steering wires 16(i) (i = 1, 2, ..., I). Here, I = 4, but I can have any other suitable value, as observed previously herein. The four steering wires 16(i) are equidistantly spaced on the circumference of the intermediate tube 312. All steering wires 16(i) are attached to the annular end portion 314, for example, by cutting from the same wall of the tube 312 as the annular end portion 314.

[0060] The deflectable end section 301 can be deflected in all directions in 3D space via four deflecting wires 16(i). In the deflectable end section 301, adjacent deflecting wires 16(i) are separated by spacers 316(i). As seen in the circumferential direction, the spacers 316(i) are located between deflecting wires 16(i) and 16(i+1). Each spacer 316(i) can be made from the wall of the intermediate tube 312 by providing a suitable cutting pattern to the wall material between adjacent deflecting wires 16(i), such that the resulting spacers 316(i) maintain a desired tangential distance between adjacent deflecting wires 16(i) while simultaneously possessing sufficient flexibility to allow the deflectable end section 301 to deflect. The flexibility depends on the cutting pattern used. See below for reference. Figure 5B Explain the cutting pattern of the spacer 316(i) that can be used.

[0061] like Figure 5BAs shown, the spacers 316(i) have a spring-shaped design. In the tangential direction of the tube 312, each spacer 316(i) extends from one steering wire 16(i) to an adjacent steering wire 16(i+1) and has a tangential cross-section equal to that of the tube 312. In this embodiment, the spacers 316(i) are not attached to the steering wires 16(i). In the axial direction of the tube 312, the spacers 316(i) have a regular repeating pattern, such as a square wave pattern, as shown. Each spacer 316(i) can be attached to an annular end portion 314 at its distal end. However, the repeating pattern can be different and more like a sinus wave pattern. This repeating pattern can be easily made by providing a suitable cutting pattern to the wall of the tube 312. The advantage of this spacer 316(i) with a square wave pattern is that it provides high flexibility in all directions for the end section 301, while simultaneously providing high rigidity against torque, as they fill a large amount of space between adjacent steering wires 16(i).

[0062] In the body section 309 adjacent to the deflectable end section 301, all the steering wires 16(i) extend parallel to each other in a continuous helical manner. In this embodiment, the steering wires 16(i) are helically rotated in multiples of 180 degrees along the total length of the body section 309 to compensate for differences in path length within the body section 309 should the body section 309 bend. However, the total amount of helical rotation depends on design requirements: for example, it may be desirable to have an additional amount of helical rotation to deflect the end section in a plane different from the plane that bends the steering section at the proximal end. Thus, the helical rotation may not fully compensate for the differences in path length within the body section due to the bending of the body section. However, this can be compensated for, for example, by a Bowden cable arrangement at the proximal end of the device, such as the Bowden cable arrangement explained and illustrated in WO 2022260518 A1.

[0063] In all sections 301, 309 of tube 312, all steering wires 16(i) may have equal thickness and width. However, depending on the design, the thickness and / or width of all steering wires 16(i) in each section 301, 309 may be different, as long as they are flexible along the entire length of the body section.

[0064] In one embodiment, near the deflectable end section 301, the tube 312 is provided with a solid-fill spacer 318(i), the distal end of which is attached to one of the spacers 316(i). Each solid-fill spacer 318(i) is located between adjacent steering wires 16(i) and 16(i+1), and in one embodiment, is attached to a spacer 316(i) inside the deflectable end section 301. The solid-fill spacers 318(i) are designed to keep adjacent steering wires 16(i), 16(i+1) separated from each other by a desired tangential distance in the body section 309. Reference numeral 319(i) indicates the location on the solid-fill spacer 318(i) where a portion 350(i) of the outer tube 340 and / or the inner tube 330 is attached to the solid-fill spacer 318(i) (see below, References). Figure 7 ).

[0065] Between each pair of adjacent steering threads 16(i), 16(i+1), a pair of spacers 320a(i), 320b(i) extend from the solid-fill spacer 318(i) in the body section 309 along the proximal direction of the tube 312. Note that in this document, the designation “16(i), 16(i+1)” includes adjacent pairs “16(i), 16(1)”. Each pair of spacers 320a(i), 320b(i) is separated by longitudinal force isolation elements 322(k), k = 1, 2, ..., K. K may, but does not have to, be equal to I. Each longitudinal force isolation element 322(k) is attached to the solid-fill spacer 318(i) at its distal end. As shown, the longitudinal force isolation element 322(k) can extend into the solid-fill spacer 318(i) by providing two longitudinal slits to the solid-fill spacer 318(i). This provides greater flexibility for the body section 309 in the region of the solid-filled spacer 318(i).

[0066] Here, an embodiment with the same number of longitudinal force isolation elements as the number of steering wires 16(i) is shown. However, this is not strictly necessary. For example, there may be more or less one longitudinal force isolation element 322(k) between two adjacent steering wires 16(i). Each longitudinal force isolation element 322(k) is shown as having an equal tangential distance from the adjacent positioned steering wires 16(i), 16(i+1). This is not strictly necessary.

[0067] The spacer pairs 320a(i), 320b(i) are designed to maintain adjacent steering wires at a predetermined distance from each other, together with the material of the longitudinal force isolation element 322(k), while still allowing the body section 309 to bend. The spacer pairs 320a(i), 320b(i) can be formed by providing a suitable cutting pattern 310 to the wall of the tube 306. For example, the cutting pattern 310 may include a plurality of slit groups, each slit group comprising several parallel slits extending tangentially from a first side of one spacer pair 320a(i), 320b(i) toward a second side of that spacer, but not completely to the second side, and several other parallel slits extending tangentially from the second side of one spacer pair 320a(i), 320b(i) toward a first side of that spacer, but not completely to the first side. However, this is only an example of the cutting pattern 310. The flexibility of the body section 309 may be less than the flexibility of the deflectable end section 301.

[0068] To provide greater rigidity against torque to tube 306, spacer pair 320(i) may be provided with one or more through holes 324, each through hole being designed to receive a radially bent lip from inner tube 330 and / or from outer tube 340. Figure 7 This lip 352 in the outer tube 340 is shown. Once the lip 352 is bent into the through hole 324, the spacer pairs 320a(i), 320b(i) will have less tangential and axial movement space relative to the inner tube 330 or outer tube 340 to which the lip 352 extends. Preferably, the tangential movement of the spacer pairs 320a(i), 320b(i) relative to the inner tube 330 and / or outer tube 340 is blocked as much as possible by these lips 352, while the axial movement of the spacer pairs 320a(i), 320b(i) relative to the inner tube 330 and outer tube 340 is allowed until a certain maximum is reached.

[0069] The longitudinal force isolation element 322(k) is not attached to adjacent spacer pairs 320a(i) and 320b(i) on its longitudinal side, nor are these spacer pairs attached to adjacent steering wires 16(i). Depending on design requirements, the longitudinal force isolation element 322(k) may have the same thickness and width as the steering wire 16(i). Together with the steering wire 16(i) and spacer pairs 320a(i) and 320b(i), the longitudinal force isolation element should provide the necessary flexibility for the body section 309 to allow insertion into curved channels.

[0070] Each longitudinal force isolation element 322(k) has a proximal end located at the proximal end of the body segment 309. The proximal ends of the longitudinal force isolation elements 322(k) are each attached to at least one of the proximal portions of the outer tube 340 or the inner tube 330. This is in Figure 5CThe figure shows a schematic longitudinal section of the proximal end of the bendable body portion 356 of the invasive instrument. The invasive instrument includes an inner tube 330, a middle tube 312, and an outer tube 340. Figure 5C The cross-sections show two opposing longitudinal force isolation elements 322(1) and 322(3). They are attached to at least one of the inner tube 330 or the outer tube 340 by means of attachments 326(1) and 326(3) at or near the proximal end of the body portion 356. The attachments 326(k) of all longitudinal force isolation elements 322(k) can be made by (laser) melting or any other suitable method.

[0071] The steering wire 16(i) extends proximally from the proximal end of the body portion 356 to the steering unit 354 of the invasive instrument, the steering unit 354 being in... Figure 5C The center is schematically indicated as a frame. This steering unit 354 can be implemented as a proximal bendable unit (such as...). Figure 3A The steering unit 244 is schematically shown in the diagram or may be implemented as a robotic device. The steering wires 16(i) may be configured such that they can be easily engaged or disengaged from (e.g., as shown in WO 2020218920, WO 2020218921 or NL 2030160 B1) a manually operable steering handle or a suitable drive mechanism of the robotic device. The steering unit 354 may be configured to convert the bending or longitudinal motion of one or more drive mechanisms into longitudinal movement of the steering wires 16(i).

[0072] Figure 6 A portion of the inner tube 330 at the distal end of the instrument is shown. The inner tube 330 has an annular end section 332, a flexible end section 334 proximal to the annular end section 332, a rigid annular section 336 proximal to the flexible end section 334, and a bendable body section 338 proximal to the annular section 336. Once the inner tube 330 is inserted into the intermediate tube 312 to the desired axial position, the annular end section 332 is axially aligned with the annular end portion 314, the flexible end section 334 is axially aligned with the deflectable end section 301, the rigid annular section 336 is axially aligned with the solid filler spacer 318(i), and the bendable body section 338 is axially aligned with the flexible spacers 320a(i) and 320b(i). The flexibility of the flexible end section 334 may be greater than that of the bendable body section 338.

[0073] By creating a suitable cutting pattern within the inner tube 330, the flexible end section 334 achieves the desired flexibility. This can be any cutting pattern known in the art or still under development. Examples could be as follows: Figure 7 The figure shown in the figure is marked with reference numeral 360 and as shown in the figure below. Figures 9 to 12CThe cutting pattern of hinge 407(j) is explained in detail, where j = 1, 2, ..., J.

[0074] By creating a suitable cutting pattern within the inner tube 330, the bendable body segment 338 can achieve the desired flexibility. This can be any cutting pattern known in the art or still under development. Examples could be as follows: Figure 7 The figure shown in the figure is marked with reference numeral 360 and as shown in the figure below. Figures 9 to 12C The cutting pattern of hinge 407(j) is explained in detail.

[0075] The rigid annular section 336 can be attached to all the solid filler spacers 318(i) in the intermediate tube 312.

[0076] Figure 7 A portion 358 of an invasive instrument having an inner tube 330, an intermediate tube 312, and an outer tube 340 arranged coaxially is shown. Details of the outer tube 340 are shown in the figure. The figure also shows the end portion 358 and the body portion 356. The body portion 356 is connected or attached at its proximal end to a steering unit 354 (see [reference]). Figure 5C (or be configured to be connected to steering unit 354.)

[0077] The outer tube 340 has an annular end section 342, a flexible end section 344 proximal to the annular end section 342, a rigid annular section 346 proximal to the flexible end section 344, and a bendable body section 348 proximal to the annular section 346. Once the inner tube 330 and the intermediate tube 312 are inserted into the outer tube 340 to the desired axial position, the annular end section 342 is axially aligned with the annular end sections 314 and 332, the flexible end section 344 is axially aligned with the flexible end section 334 and the deflectable end section 301, the rigid annular section 346 is axially aligned with the annular section 336 and the solid filler spacer 318(i), and the bendable body section 348 is axially aligned with the bendable body section 338 and the flexible spacer pairs 320a(i) and 320b(i). The flexibility of the flexible end section 344 can be higher than that of the bendable body section 348.

[0078] By creating a suitable cutting pattern within the outer tube 340, the flexible end section 344 achieves the desired flexibility. This can be any cutting pattern known in the art or still under development. Examples could be such as... Figure 7 The figure shown in the figure is marked with reference numeral 360 and as shown in the figure below. Figures 9 to 12C The cutting pattern of hinge 407(j) is explained in detail.

[0079] By creating a suitable cutting pattern in the outer tube 340, the bendable body segment 348 achieves the desired flexibility. This can be any cutting pattern known in the art or still under development. It can be the same cutting pattern applied in the flexible end segment 344.

[0080] The rigid annular segment 346 can be attached at position 350(j) to all the solid filler spacers 318(i) in the intermediate tube 312. That is, each solid filler spacer 318(i) in the intermediate tube 312 is attached to at least one of the annular segment 336 of the inner tube 330 or the annular segment 346 of the outer tube 340. This can be accomplished by (laser) welding or any other known attachment technique. For this purpose, the outer tube 340 can have small lips at position 350(j) that can be melted by a laser beam, such that the molten lip material is welded to the solid filler spacers 318(i).

[0081] Figure 7 The body section 348 is also shown to have one or more lips 352. Once the intermediate tube 312 (and possibly the inner tube 330) is in place, each of these lips 352 bends inward such that each lip inserts into one of the through holes 324 in the spacer pairs 320a(i), 320b(i). Once inside these through holes 324, they restrict the tangential and axial movement of the spacer pairs 320a(i), 320b(i) relative to the outer tube 340.

[0082] In another embodiment, the force isolation element 322(k) itself may be provided with a through hole 325, such as Figure 5D As shown, the lip of the inner tube 330 and / or the outer tube 340 (e.g. Figure 7 The lip 352 shown is inserted through these through holes. The tangential movement of the force isolation element 322(k) relative to the inner tube 330 and / or the outer tube 340 is then blocked as much as possible by these lips, while the axial movement of the force isolation element 322(k) relative to the inner tube 330 and the outer tube 340 is allowed until a certain maximum is reached. Furthermore, this through hole 325 is configured such that the force isolation element 322(k) has a certain required flexibility to allow the body section 309 to be bent while also having sufficient longitudinal stiffness. That is, the desired flexibility of the force isolation element 322(k) can be achieved by appropriately selecting the axial length and / or tangential width of the through hole 325.

[0083] Figure 5E It shows Figure 5DAn alternative embodiment of the embodiment, wherein the through-hole has the form of an elongated slot 325, such that, in other words, the force isolating element 322(k) is divided into two parallel force isolating sub-elements 322(k, 1) and 322(k, 2), which are attached to each other by one or more small bridges 323 extending tangentially or at a small angle thereto. The lengths of the slots 325 may all be equal. However, they may be designed differently such that the bending stiffness of the body section of the device varies depending on the axial position.

[0084] As those skilled in the art will understand, Figure 5E The bending stiffness of the body shown will depend strongly at all locations on those portions 322(k, 1), 322(k, 2), 323 of the force isolating element whose tangential direction extends at a small angle relative to the bending direction. If the thickness of the force isolating element is less than its width, those portions 322(k, 1), 322(k, 2), 323 of the force isolating element that do not bend at all or bend at an angle closer to 90 degrees relative to the bending direction of the device will have a much smaller effect on the bending stiffness.

[0085] The actual bending stiffness at a certain axial position of the body section depends on whether there is a slot 325 or a bridge 323 at that axial position. If a bridge 323 is present, the bending stiffness is greater than if a slot 325 is present.

[0086] Of course, force isolation 322(k) can be divided into more than two force isolation sub-elements.

[0087] At the axial location where the slot 325 exists, the bending stiffness of the body section depends on the widths w1 and w2 of the two parallel force-isolating sub-elements 322(k, 1) and 322(k, 2) (as measured in the tangential direction), see [reference]. Figure 5E These individual widths w1 and w2 can be equal or different. Furthermore, these widths w1 and w2 can vary depending on the position measured in the axial direction.

[0088] The actual bending stiffness also depends on the thickness of the force isolation elements 322(k, 1) and 322(k, 2). These elements have a rectangular cross-section and a width of [missing information] at a certain location. w The flat strip filament has an area moment of inertia at this location. I ,in I ∝ t w^3 ,in t =The thickness of the wire (in the current example, this is seen in the radial direction of the instrument) and w= The width of the wire (in the current example, this is seen in the tangential direction of the instrument). Therefore, the bending stiffness is closely related to the width of the wire. Of course, in practical embodiments where the wire is produced by cutting in a tube, the wire has a cross-section in the form of a partially circular arc as seen in the tangential direction. Therefore, this equation is only an indication of the actual area moment, but it provides a good indication of the dependence on the width of the wire.

[0089] Therefore, the bending stiffness of the force isolation element 322(k) at the axial position of the slot 325 depends on (w1 + w2 + w3)^3 - w3^3 ,in, w1 It is the width of the force isolation sub-element 322(k, 1), and w2 w3 is the width of the force isolating element 322(k,2), and w3 is the width of the slot or bridge. However, the bending stiffness of the force isolating element 322(k) at the axial position of the bridge 323 depends on... (w1 + w2 + w3)^3 ,in, w1 It is the width of the force isolation element 322(k, 1). w2 It is the width of the force isolation sub-element 322(k, 2), and w3 That is the width of bridge 323.

[0090] Figure 5F It shows Figure 5D An alternative design. Instead of in Figure 5E In the embodiments, the elements are attached to each other by one or more bridges 323, and two adjacent force isolation sub-elements 522(k, 1), 522(k, 2) are separated by one or more spacers 327. Successive spacers 327 may be alternately attached to one of the two force isolation sub-elements 322(k, 1), 322(k, 2) and contact only the other force isolation sub-element. Slots 325 are also present between the successive spacers 327.

[0091] exist Figure 5F In the embodiments, just like in Figure 5E As in the embodiment, the bending stiffness of the force isolation element 322(k) at the axial position of the slot 325 depends on w1^3 + w2^3 ,in, w1 It is the width of the force isolation sub-element 322(k, 1), and w2 This is the width of the force isolating sub-element 322(k, 2). However, the bending stiffness of the force isolating element 322(k) at the axial position of the spacer element 327 attached to the force isolating sub-element 322(k, 1) or 322(k, 2), respectively, depends on... w2^3 + (w1 + w3)^3 or w1^3 + (w2 + w3)^3 ,in w1It is the width of the force isolation element 322(k, 1). w2 It is the width of the force isolation sub-element 322(k, 2), and w3 This is the width of the spacer element 327. Therefore, at the axial position of the spacer element 327, Figure 5F The force isolation element 322(k) of the embodiment has a higher strength than Figure 5E The force isolation element 322(k) has lower bending stiffness.

[0092] As can be seen in the attached diagram, in Figure 5D , Figure 5E and Figure 5F In this embodiment, spacer pairs 320a(i) and 320b(i) are absent. That is, one or both of spacer pairs 320a(i) and 320b(i) can be omitted, and force isolation elements 322(k) can be designed to also act as tangential spacers between adjacent steering wires 16(i). The tangential movement of these force isolation elements 322(k, 1), 322(k, 2) acting as tangential spacers can be blocked relative to the tube inside and / or outside the tube in which the force isolation elements 322(k, 1), 322(k, 2) are manufactured, for example, by bending one or more lips 352 from the external and / or internal tubes into the slot 325. Such lips 352 can have the same width as the slot 325 (as seen in the tangential direction), such that they are clamped in the slot after being bent into the slot 325. They can also be slightly smaller than the width of the slot 325 in order to allow such a lip 352 to slide in the slot 325 in the axial direction, which may be necessary when path length changes occur within the body section 309.

[0093] It was observed that if an instrument with a flexible shaft is developed without a helical design, the spacer element cannot be a force-isolating element 322(k), but should be a separate part attached (welded or secured using snap-fit / bendable lip) between the two steering threads 16(i). Therefore, a large number of separate spacer elements exist (which requires significant cutting and assembly time and carries the risk of loosening during production or during instrument failure in use). For flexible instruments, these elements need to be smaller than the anchor chain distance (the gap between hinges) to maintain the flexibility of the instrument. These spacer elements can be linked with flexible hinges / connectors to reduce the number of loose parts. Alternatively, openings can be formed in the element in which it is attached to the top layer to hold it in place but allows axial movement. However, the relatively large stroke compensation required due to the length deviation introduced by the bending of the shaft necessitates that these openings become larger than the element itself.

[0094] This will refer to Figure 5G and Figure 5H Further explanation. Figure 5G A prior art steerable tube known from WO 2009 / 098244 is shown. The figure shows a tube 500 having a distal end (left) and a proximal end (right). The tube has a plurality of steerable wires 502(i) cut from the tube 500 and extending from the proximal end to the distal end. At the proximal end, each steerable wire 502(i) is attached to a proximal ring 508p via a flexible steerable wire portion 504(i). At the distal end, each steerable wire 502(i) is attached to a distal ring 508d via a flexible steerable wire portion 506(i). Adjacent steerable wires 502(i) are separated by a spacer element having a distal spacer element portion 510d, an intermediate spacer element portion 510m, and a proximal spacer element portion 510p. The distal spacer element portion 510d and the proximal spacer element portion 510p are attached to the distal ring 508d and the proximal ring 508p, respectively. The intermediate spacer element portion 510m is resistant to bending, meaning it cannot or almost cannot be bent. Both the distal spacer element portion 510d and the proximal spacer element portion 510p have a wavy pattern.

[0095] Figure 5G The existing tubing cannot be used in devices with flexible intermediate sections that will be guided through a tortuous path. Firstly, the intermediate spacer element portion 510m is bend-resistant and therefore not designed to bend. Secondly, the intermediate spacer element portion 510m is straight. Therefore, even when they are flexible, bending of the intermediate section will result in different intermediate spacer element portions 510m having portions of varying path lengths within the intermediate section. Some will need to extend into the flexible distal end and / or flexible proximal end, while others will occupy a path length smaller than the available path length in the intermediate section. When bending, these variations in path length at different sides of the tube need to be compensated for in the flexible distal end and / or flexible proximal end. WO 2009 / 098244 does not address this.

[0096] In embodiments, the invention enables the spacers between adjacent steering wires 16(i) to be implemented as uninterrupted wires in a device having a flexible body segment that will be guided through a tortuous path (e.g., through a blood vessel or intestine within the (human) body). As described above, by spiraling the steering wires 16(i) and the uninterrupted spacer wires between them, variations in path length within the body segment can be compensated. Theoretically, at least 360 degrees of spiraling is required to compensate for the length difference so that the passive shaft bends at a continuous radius along its entire length. Controlling the degree of spiraling can be used to control the bending characteristics of the device.

[0097] Preferably, if only the length difference within a plane is to be compensated, the helical rotation measured between the distal and proximal ends is a multiple of 360 degrees or at least a multiple of 180 degrees.

[0098] exist Figure 5H The text shows the relationship with... Figure 5E The same implementation method, but all reference numerals related to the force isolation elements are marked with an "s": their ends are no longer attached to the... Figure 5H The inner and / or outer tubes shown should be noted to still be attached to such inner and / or outer tubes, but only at one end. Therefore, they are no longer used as force isolation elements, but only as uninterrupted spacer wires 322s(k) between adjacent steering wires 16(i). These uninterrupted spacer wires 322(k) can be divided into two or more sub-spacer wires 322s(k, 1), 322s(k, 2), which are separated by one or more slots 325s and attached by one or more bridges 323s, as shown. Figure 5H As shown. Of course, other implementations are also possible, for example... Figure 5F The implementation method shown.

[0099] Note that this spacer wire 322s(k) can also be applied between other elements besides the steering wire 16(i). That is, this spacer wire 322s(k) can be applied between the first portion and the second portion of tube 306. The first portion can be the steering wire 16(i), but it can also be a control wire, which is manufactured by cutting (or removing from other materials) a pattern from tube 306 and is configured to control the function of the instrument to which tube 306 is a part, such as a locking / unlocking function or any other function as detailed in the applicant's WO 2023 / 287289.

[0100] exist Figure 5H In embodiments thereof, or alternative embodiments, actual bending of the body section can still result in some variation in the path length of the spacer wires 322s(k) in that body section 309. This can be compensated for by providing axial flexibility to the spacer wires 322s(k) in at least one of the distal end (i.e., the deflectable end section 301) and the proximal end (i.e., the flexible portion 203). This can be implemented by providing a wavy pattern to the spacer wires 322s(k) in at least one of the distal and proximal ends, such as... Figure 5G As shown. Alternatively, other path length compensation mechanisms may be used at the far and / or near ends, as detailed in the applicant's WO 2022260518A1.

[0101] Figure 5H An example can be defined as follows: A steerable tube (312) includes a deflectable end section (301) at a distal end and a flexible body section (309) proximal to the deflectable end section (301); one or more steering wires (16(i)) configured to deflect the deflectable end section (301) and helically rotate in a circumferential direction of the steerable device in at least a portion of the flexible body section (309); and one or more spacer wires (322s(k)) providing tangential spacing between a first portion and a second portion of the tube (312), the spacer wires (322s(k)) extending in at least the entire flexible body section (309) and helically rotating in the flexible body section (309) like the one or more steering wires (16(i)).

[0102] Figure 5A , Figure 5B , Figure 5C , Figure 5D , Figure 6 and Figure 7 The embodiment is based on all steering threads rotating continuously in a spiral around the central tube 312 in positive integer multiples of 180 degrees. In alternative embodiments, similar... Figure 4 The illustrated discrete system comprises a body section divided into multiple body sub-sections, and a 180-degree helical rotation is applied only to some of these sub-sections, while other sub-sections consist of straight steering wires extending parallel to each other and parallel to the central axis. In a further embodiment, for example, when there are specific requirements regarding the plane in which the end section should deflect, the total helical rotation may differ from a positive integer multiple of 180 degrees around the intermediate tube 312. The path length compensation may then be imperfect, but can be compensated for, for example, by implementing additional Bowden cable arrangements for both the steering wire 16(i) and the force isolation element 322(k) at the proximal end of the instrument, such as... Figure 5C Box 355 in the diagram is indicated schematically. One of the Bowden cable arrangements, as shown and explained in WO 2022260518A1, can be applied, for example.

[0103] As mentioned above, in Figure 5A , Figure 5B , Figure 5C , Figure 5D , Figure 6 and Figure 7In this embodiment, all longitudinal force isolation elements 322(k) are attached at their distal end, at a location at the distal end of the body section 309, to at least one of the inner tube 330 or outer tube 340, and at their proximal end, at a location at the proximal end of the body section 309, to at least one of the inner tube 330 or outer tube 340. Thus, the axial loads on the instrument body section caused by bending the body section and / or operating the steering wire 16(i) to deflect the end portion 358 are borne by these longitudinal force isolation elements 322(k). Therefore, the thrust and pull forces applied by the steering wire 16(i) to deflect the end portion 358 are isolated from the body portion 356. It turns out that these thrust and pull forces in the helical guide wire 16(i) are balanced much more effectively than in prior art settings, and therefore, when the end portion 358 of the invasive instrument is operated, there is less undesirable movement of the body portion 356 of the helical guide wire 16(i) due to the resulting torque load.

[0104] In practice, depending on the design and curvature of the curved channel into which the invasive instrument is inserted, full path length compensation may not be achievable, meaning offset errors may remain. If only a short length of the flexible body segment of the instrument is bent, and if that length is less than one helical cycle of 180 degrees, a small length offset difference arises between the steering wire 16(i) and the longitudinal force isolation element 322(k). This can lead to a muscular effect on the axis of the instrument.

[0105] For the aforementioned discrete systems, this offset error in path length compensation will be greater. The maximum residual offset error of the instrument is determined by the length of the body sub-segments in which the steering wire extends in a straight line, the length between these body sub-segments where both the steering wire and the longitudinal force isolation element rotate 180 degrees, and the maximum angle at which these body sub-segments can be bent. The more body sub-segments in which the steering wire and longitudinal force isolation element rotate 180 degrees, and the shorter the body sub-segments in which the steering wire and longitudinal force isolation element extend in a straight line, the smaller the possible residual error.

[0106] Even for such Figure 5A , Figure 5B , Figure 5C , Figure 5D , Figure 6 and Figure 7The apparatus shown, in which the steering wire 16(i) and the longitudinal force isolation element 322(k) rotate continuously in a spiral around the intermediate tube 312 along the entire body section 309, may still exhibit small errors in path length compensation when the body section bends only a portion of its entire length, especially when the bend is less than the length of the 180-degree spiral portion. This effect becomes smaller as the pitch of the spiral steering wire 16(i) and the longitudinal force isolation element 322(k) decreases.

[0107] To avoid or at least minimize this offset error and therefore any muscle effect in the proximal segment of the device, an additional “coiled tube” or Bowden cable segment can be applied near the proximal end of the proximal segment, such as… Figure 5C It is schematically indicated by reference numeral 355 in the accompanying drawings. Figure 5C In the diagram, Bowden cable segment 355 is depicted within turning segment 354; however, alternatively, this Bowden cable segment may exist between the proximal end of body segment 356 and turning segment 354. WO2022260518 A1 discloses an example of such coiled tubing or Bowden cable segments manufactured entirely by cutting components from a tube (laser). They all compensate for path length differences in the body segment caused by bending the body segment, as the coiled tubing or Bowden cable segment more or less absorbs the turning wire length in the body segment without causing deflection of the deflectable end segment and without causing proximal deflection of the instrument. All embodiments explained in WO 2022260518 A1 can be used as additional path length compensation mechanisms for both the turning wire 16(i) and the force isolation element 322(k) in embodiments of the present invention. Since the possible residual offset error in the current embodiment is relatively small, these known coiled pipe or Bowden cable arrangements do not require large and may only require relatively small spaces.

[0108] It was observed that, as in the reference Figure 5A , Figure 5B , Figure 5C , Figure 5D , Figure 6 and Figure 7 The explained path length-compensated invasive device can be easily manufactured using only three tubes. This embodiment is simpler than the embodiment disclosed in WO 2022260518 A1 and avoids the use of a flexible shaft to control potential bending forces on the device at the proximal end, as in that patent application.

[0109] It was observed that, Figure 5A , Figure 5B , Figure 5C , Figure 5D , Figure 6 and Figure 7The embodiments shown depict three tubes, with all components made by creating suitable cutting patterns within these tubes. However, the invention is not limited to applications with three tubes. For example, the device may have more tubes. The steering wire 16(i) may have separate sections made of tubular material that are interconnected or attached to each other, as explained in WO 2017213491. Furthermore, the device may have other longitudinal elements made of tubular material and configured to perform functions other than steering the end or isolating forces, such as locking or unlocking the curvature of a portion of the body portion, as explained in WO 2023287289.

[0110] Although the invasive device is shown as having a single deflectable tip, the invention is not limited thereto. That is, the invasive device may have multiple deflectable tip portions.

[0111] All tubes 330, 312, and 340 may have one of a circular, oval, elliptical, or rectangular cross-section.

[0112] All tubes 330, 312, and 340 may be made at least in part from at least one of the following groups of materials: Biocompatible polymer materials, including polyurethane, Polyethylene or polypropylene, Stainless steel, Cobalt and chromium Shape memory alloys, such as Nitinol®, plastic, polymer, Composite materials, or Other curable materials.

[0113] In embodiments, the components of these tubes (including the one or more steering wires 16(i) and the one or more longitudinal force isolation elements 322(k)) are produced by a material removal technique applied to the wall of at least one tube 312 to form a suitable cutting pattern. This material removal technique includes at least one of photochemical etching, deep pressing, chip cutting, laser cutting, or water jet cutting. The material removal means may be a laser beam that melts and evaporates the material, or a water jet cutting beam, and this beam may have a width of 0.01 to 2.00 mm, more typically between 0.015 and 0.04 mm in this application.

[0114] The wall thickness of the tube depends on its application. For medical applications, the wall thickness can range from 0.03 to 2.0 mm, preferably 0.03 to 1.0 mm, more preferably 0.05 to 0.5 mm, and most preferably 0.08 to 0.4 mm. The diameter of the tube depends on its application. For medical applications, the diameter can range from 0.5 to 20 mm, preferably 0.5 to 10 mm, and more preferably 0.5 to 6 mm. The radial clearance between adjacent tubes can range from 0.01 to 0.3 mm.

[0115] The features of the present invention explained with reference to the foregoing figures can be summarized as follows.

[0116] The present invention relates to a steerable device having a deflectable end portion (358) at a distal end and a bendable body portion (356) proximal to the end portion (358), the steerable device comprising at least one tube (312) and at least one of an inner tube (330) within the at least one tube (312) or an outer tube (340) outside the at least one tube (312), and one or more steering wires (16(i)) in the at least one tube (312), the at least one tube (312) comprising a deflectable end section (301) in the deflectable end portion (358) and a bendable body portion (356). The flexible body section (309) in part (356), wherein one or more steering wires (16(i)) are helically rotated in at least a portion of the flexible body section (309) in the circumferential direction of the steerable device, the steerable device further includes one or more longitudinal force isolation elements (322(k)) in the at least one tube (312), the longitudinal force isolation elements (322(k)) being arranged parallel to the one or more steering wires (16(i)) in the flexible body section (309), wherein the one or more longitudinal force isolation elements (322(k)) have a distal end and a proximal end, and apply one of the following features: If the steerable device includes the outer tube (340), the distal end of each longitudinal force isolation element (322(k)) is attached to the outer tube (340) at the distal end of the body section (309), and the proximal end of each longitudinal force isolation element (322(k)) is attached to the outer tube (340) at the proximal end of the body section (309), or If the steerable device includes the inner tube (330), the distal end of each longitudinal force isolation element (322(k)) is attached to the inner tube (330) at the distal end of the body section (309), and the proximal end of each longitudinal force isolation element (322(k)) is attached to the inner tube (330) at the proximal end of the body section (309), or If the steerable device includes the inner tube (330) and the outer tube (340), the distal end of each longitudinal force isolation element (322(k)) is attached at the distal end of the body section (309) to at least one of the inner tube (330) or the outer tube (340), and the proximal end of each longitudinal force isolation element (322(k)) is attached at the proximal end of the body section (309) to at least one of the inner tube (330) or the outer tube (340).

[0117] The one or more steering wires (16(i)) can be helically rotated 180 degrees in the circumferential direction of the steering device in at least a portion of the flexible body section (309) to provide path length compensation due to bending of the at least a portion of the flexible body section (309).

[0118] The one or more steering wires (16(i)) can be helically rotated an equal number of 180 degrees in a certain number of portions of the flexible body section (309) in the circumferential direction of the steerable device to provide path length compensation due to bending of one or more of the portions of the flexible body section (309).

[0119] The one or more steering wires (16(i)) can rotate in a continuous manner along the entire flexible body section (309).

[0120] In such a steerable device, a plurality of steering wires (16(i)) can be arranged in parallel at equidistant positions in the tangential direction of the at least one tube (312), which can have a plurality of longitudinal force isolation elements (322(k)), at least one of which is located between two adjacent steering wires (16(i), 16(i+1)).

[0121] Each longitudinal force isolation element (322(k)) can be attached to a spacer (318(i)) configured to maintain two adjacent steering wires (16(i)) at a desired tangential distance, and If the steerable device includes the outer tube (340), then the distal end of each longitudinal force isolation element (322(k)) is attached to the outer tube (340) via the spacer (318(i)) and the attachment thereto, or If the steerable device includes the inner tube (330), then the distal end of each longitudinal force isolation element (322(k)) is attached to the inner tube (330) via the spacer (318(i)) and the attachment thereto, or If the steerable device includes the inner tube (330) and the outer tube (340), the distal end of each longitudinal force isolation element (322(k)) is attached to at least one of the inner tube (330) or the outer tube (340) via the spacer (318(i)).

[0122] A longitudinal force isolation element (322(k)) may exist, which is arranged between two adjacent steering wires (16(i), 16(i+1)) and is equidistant from the two adjacent steering wires.

[0123] A pair of flexible spacers (320a(i), 320b(i)) may be disposed between two adjacent steering wires (16(i), 16(i+1)) and near the spacer (318(i), wherein the first flexible spacer of the pair of flexible spacers (320a(i), 320b(i)) is located between a single longitudinal force isolation element (322(k)) and the first steering wire of the two adjacent steering wires (16(i), 16(i+1)), and the second flexible spacer of the pair of flexible spacers (320a(i), 320b(i)) is located between the single longitudinal force isolation element (322(k)) and the second steering wire of the two adjacent steering wires (16(i), 16(i+1)).

[0124] The at least one tube (312) may include an annular end portion (314) at its distal end, to which one or more steering wires (16(i)) are attached.

[0125] At least one of the longitudinal force isolation elements (322(k)) may be provided with a through hole (325), with a lip extending through the through hole (325) from the inner tube (330) or the outer tube (340), respectively. The lip and the through hole (325) are configured to block tangential movement of the longitudinal force isolation element (322(k)) relative to the inner tube (330) or the outer tube (340), respectively, but allow axial movement.

[0126] The end section of the at least one tube (312) may include spacers (316(i)) between every two adjacent turning wires (16(i), 16(i+1)), each spacer (316(i)) having a regular wave pattern, such as a square wave or a sinus wave pattern.

[0127] The steerable device may have a Bowden cable section (355) on the proximal side of the proximal end of the body section (356) to compensate for the offset of the path length difference of these steering wires (16(i)).

[0128] Hinge structure On the other hand, the present invention relates to a hinge structure, namely, Figure 7 The hinge structure is shown in the attached figure at 360°. As an introduction to a detailed description of this hinge structure, it will first be described... Figure 8 The image is from WO 2018067004. Figure 9 Copying.

[0129] Figure 8 Hinge structure 402 in tube 400 is shown. Hinge structure 402 is shown as having two identical hinges 401(1), 401(2), but these identical hinges 401(1), 401(2) are rotated 90 degrees in the tangential direction of tube 400. The same reference numerals without “(1)” or “(2)” refer to the same parts of the corresponding hinges 401(1), 401(2).

[0130] Hinge 401(1) is made of a cut pattern in tube 400. The cut pattern defines the distal (i.e., left) and proximal (i.e., right) sides of hinge 401(1). The distal and proximal sides are connected to each other by two identical longitudinal bridges, one of which is shown by reference numeral 404(1). The other is in Figure 8 It is not visible in the middle, but its position is rotated 180 degrees relative to the longitudinal bridge 404(1) in the tangential direction of the tube 400. The longitudinal bridge 404(1) is a strip made of two parallel longitudinal slits 406(1) and 408(2) extending in the longitudinal direction of the tube 400 in the wall material of the tube 400. The two parallel longitudinal slits 406(1) and 408(2) have the same length. The longitudinal bridge 404(1) has a rotation center 426(1).

[0131] A first tangential slit 410(1) extends from the longitudinal slit 406(1) along a first tangential direction of the tube 400. The first tangential slit 410(1) connects to the longitudinal slit 406(1) at the center of the longitudinal slit 406(1). The first tangential slit 410(1) covers a tangential range of less than 180 degrees. The first tangential slit 410(1) is interrupted by a first lip portion 412(1) on the distal side of the hinge 401(1). The first lip portion 412(1) extends in the longitudinal direction of the tube 400 into a first opening 414(1) on the proximal side of the hinge 401(1). The first lip portion 412(1) and the opening 414(1) are separated by a small slit 428(1) such that the outer surface of the first lip portion 412(1) matches the inner surface of the first opening 414(1), and the first lip portion 412(1) can move freely within the first opening 414(1).

[0132] A second tangential slit 418(1) extends from the longitudinal slit 408(1) along a second tangential direction of the tube 400. The second tangential direction is opposite to the first tangential direction. A second tangential slit 410(1) connects to the longitudinal slit 408(1) at the center of the longitudinal slit 408(1). The second tangential slit 418(1) covers a tangential range of less than 180 degrees. The second tangential slit 418(1) is interrupted by a lip portion 420(1) on the distal side of the hinge 401(1). The lip portion 420(1) extends in the longitudinal direction of the tube 400 into an opening 422(1) on the proximal side of the hinge 401(1). The lip portion 420(1) and the opening 422(1) are separated by a small slit 430(1) such that the outer surface of the lip portion 420(1) matches the inner surface of the opening 422(1) and the lip portion 420(1) can move freely within the opening 422(1).

[0133] The lip portion 412(1) has a first curved side extending along a portion of a first circle C1, the center of which coincides with the rotation center 426(1) of the longitudinal bridge 404(1). The lip portion 412(1) has a second curved side opposite to the first curved side, the second curved side extending along a portion of a second circle C2, the center of which also coincides with the rotation center 426(1) of the longitudinal bridge 404(1).

[0134] The lip portion 420(1) has a third curved side extending along a portion of the first circle C1 and a fourth curved side extending along a portion of the second circle C2 opposite to the third curved side.

[0135] Longitudinal bridge 404(1), longitudinal slits 406(1), 408(1), tangential slits 410(1), 418(1), lip portions 412(1), 420(1), and openings 414(1), 422(1) define a first cutting pattern in tube 400. A second cutting pattern identical to the first cutting pattern exists in tube 400 at a position rotated 180 degrees. Figure 8 The end portion of the second cutting pattern corresponding to the tangential slit 416(1) of the first cutting pattern is shown, as well as the end portion of the second cutting pattern corresponding to the tangential slit 410(1) of the first cutting pattern.

[0136] Tangential slits 416(1) and 424(1) also extend in the tangential direction for a length less than 180 degrees. The tangential slits 410(1) of the first cutting pattern and 416(1) of the second cutting pattern do not coincide in any position, but overlap in the tangential direction, such that a tangential bridge 403(1) extending in the tangential direction exists between them. One end of the tangential bridge 403(1) is attached to the distal side of the hinge 401(1), and the other end is attached to the proximal side of the hinge 401(1). The tangential slits 418(1) of the first cutting pattern and 424(1) of the second cutting pattern do not coincide in any position, but overlap in the tangential direction, such that a tangential bridge 405(1) extending in the tangential direction exists between them. One end of the tangential bridge 405(1) is attached to the distal side of the hinge 401(1), and the other end is attached to the proximal side of the hinge 401(1).

[0137] The first and second cutting patterns allow the tube 400 to bend by rotating the far and near sides of the hinge 401(1) in opposite directions within a first plane perpendicular to the virtual line of the center of rotation of the longitudinal bridge 426(1) passing through the center of rotation of the longitudinal bridge 404(1) and the center of the longitudinal bridge of the second cutting pattern on the opposite side of the tube 400.

[0138] In use, it may be desirable to rotate the tube 400 about its central axis 29, which results in torque in the tube 400. Torsional forces may damage the hinge 401(1) through deformation or breakage of the wall material of the tube 400. Tangential bridges 403(1) and 405(1) will absorb such torsional forces to a degree that depends on their elasticity, which is determined by the wall material and the dimensions of the tangential bridges.

[0139] After a minimum amount of relative tangential rotation is allowed by the lip portions 412(1), 420(1) within the openings 414(1), 422(1) and their invisible counterparts of the second cutting pattern, the relative tangential rotation between the distal and proximal sides of the hinge 401(1) is blocked by the lip portions 412(1) and correspondingly 420(1) with the slits between the openings 414(1) and correspondingly 422(1). In this way, the invisible counterparts of the lip portions 412(1), 420(1) and their second cutting patterns further counteract the potential damaging effects of torsional forces.

[0140] Figure 8Some components of hinge 401(2) are shown, which is identical to hinge 401(1) but rotated 90 degrees relative to hinge 401(1). Tube 400 has a distal portion located far from hinge 401(2) and a proximal portion located near hinge 401(2). Hinge 401(2) also has two opposing longitudinal bridges with corresponding centers. Thus, hinge 401(2) allows these distal and proximal portions to rotate relative to each other in a second plane perpendicular to a virtual line passing through the two centers of the two longitudinal bridges. The second plane is perpendicular to the aforementioned first plane, thereby allowing hinge structure 402, including hinges 401(1) and 401(2), to bend in three dimensions. Hinge structure 402, as shown, can be repeated multiple times in tube 400, allowing tube 400 to bend in three dimensions along its longer length.

[0141] The lip portions 412(1), 420(1), 412(2), and 420(2) should have certain dimensions, especially in the longitudinal direction, so as to be effective and not too easily damaged by torsional forces. Therefore, they may limit further miniaturization of the tube 400. This aspect of the invention solves this problem, as referenced... Figures 9 to 12C The explanation given.

[0142] exist Figure 9 In this figure, a side view of the first hinge 407(1) of the hinge structure 360 ​​of the present invention is shown, and the same reference numerals as used in the previous figures are used to refer to the same parts. It can be observed that this hinge structure can be applied to any bendable tube, and not just to… Figures 1A to 7 In the illustrated device, such a bendable tube can be, for example, part of any type of bendable invasive instrument used in endoscopic applications. Such a bendable invasive instrument can have one or more deflectable ends that can be deflected by a suitable deflection section 354 at the proximal end. The deflection wire can be a strip produced by creating a suitable cutting pattern in one or more coaxial tubes, or it can be a cable. They can be straight or spiral in the instrument.

[0143] exist Figure 9 In the 400 tube (see also) Figure 10(A three-dimensional view), the tangential slit 410(1) includes tangential slit portions 410a(1), 410b(1), and the tangential slit 418(1) includes tangential slit portions 418a(1), 418b(1). The tangential slit portions 410a(1), 410b(1) are connected to each other and have corresponding ends 409(1), 419(1). The tangential slit portions 410a(1), 410b(1) extend from the end 409(1) to the end 419(1) and partially surround the tube 400 in the tangential direction E. In an embodiment, the tangential slit portion 410a(1) tapers toward the end 409(1), and the tangential slit portion 410b(1) tapers toward the end 419(1). However, the tangential slit portions 410a(1), 410b(1) may have a single width along their length, and both widths may be the same.

[0144] Tangential slit portions 418a(1) and 418b(1) are connected to each other and have corresponding ends 411(1) and 413(1). Tangential slit portions 418a(1) and 418b(1) extend from end 411(1) to end 413(1) and partially surround the tube in the tangential direction F. In an embodiment, tangential slit portion 418a(1) tapers toward end 411(1), and tangential slit portion 418b(1) tapers toward end 413(1). The taper of tangential slit portion 410a(1) may be equal to the taper of tangential slit portion 418a(1), and the taper of tangential slit portion 410b(1) may be equal to the taper of tangential slit portion 418b(1). Furthermore, the tangential slit portions 418a(1) and 418b(1) may have a single width along their length, and both widths may be the same and the same as the widths of the tangential slit portions 410a(1) and 410b(1).

[0145] Tangential directions E and F are opposite directions. Ends 409(1) and 411(1) lie on the same circumference in a plane perpendicular to the central axis 29, which extends in the longitudinal direction of the tube 400. Ends 409(1) and 411(1) are arranged to face each other.

[0146] End 409(1) coincides with the center of longitudinal slit 406(1), and end 411(1) coincides with the center of longitudinal slit 408(1). Both longitudinal slits extend longitudinally along the tube 400, thus defining the longitudinal side of the longitudinal bridge 404(1). Ends 409(1) and 411(1) may coincide with another portion of longitudinal slits 406(1) and 408(1), respectively.

[0147] As shown in the figure, the longitudinal slits 406(1) and 408(1) can be bent in opposite directions, such that the longitudinal bridge 404(1) has a minimum width at a position that can be located at the center of the total length of the longitudinal bridge 404(1). t .width t The length LB1 of the longitudinal slit 406(1) can be between 0.3 and 4 mm. The length LB2 of the longitudinal slit 408(1) can be between 0.3 and 4 mm. The length LB1 can be equal to the length LB2. The shape of the longitudinal slit 406(1) can coincide with a portion of the first circle CB1 having a first radius of 0.5-10 mm. The shape of the longitudinal slit 408(1) can coincide with a portion of the second circle CB2 having a second radius of 0.5-10 mm. The radius of the second circle CB2 can be equal to the radius of the first circle CB1. Here is the width. t The values ​​provided for the lengths LB1 and LB2, as well as the radii of CB1 and CB2, are applicable to tubular instruments with radii between 1 and 15 mm and wall thicknesses between 0.08 and 2 mm.

[0148] Therefore, compared to the case where the longitudinal bridge 404(1) has an equal width along its length, the longitudinal bridge 404(1) has a better defined center of rotation 426(1) at its center (the portion of the tube 400 located on the opposite side of the longitudinal direction of the bridge 404(1) can be bent around this center of rotation), thus providing more accurate movement for the instrument.

[0149] In this embodiment, the tangential directions E and F lie in a plane perpendicular to the central axis 29 of the tube 400. However, direction E may form an angle with this plane. The tangential direction F may also form an angle with this plane. These angles may be between -20° and +20°, or between -10° and +10°, more preferably between -8° and +8°. They may have the same value.

[0150] Tangential slit portions 410a(1) and 410b(1) are located at longitudinally offset positions and are respectively connected at opposite ends of a longitudinal channel 425(1) that extends in the longitudinal direction of the instrument 400 to form a tangential shoulder structure. The sidewalls of the longitudinal channel 425(1) are defined by walls 442(1) and 440(1) that extend in the longitudinal direction of the instrument between the tangential slit portions 410a(1) and 410b(1). In an embodiment, walls 442(1) and 440(1) are straight. However, they may have a curvature that coincides with a portion of a circle centered on a rotation center 426(1) so that the movement of the hinge during rotation is aligned with the rotation center 426(1). In the non-bending positions of the distal and proximal sides of the hinge 407(1), as seen in the tangential direction of the instrument, walls 442(1) and 440(1) partially overlap. The overlap can be between 0.05 and 3 mm.

[0151] Tangential slit portions 418a(1) and 418b(1) are located at longitudinally offset positions and are respectively connected at opposite ends of a longitudinal channel 427(1) extending in the longitudinal direction of the instrument 400 to form a tangential shoulder structure. The sidewalls of the longitudinal channel 427(1) are defined by walls 446(1) and 444(1) extending in the longitudinal direction of the instrument between the tangential slit portions 418a(1) and 418b(1). In an embodiment, walls 446(1) and 444(1) are straight. However, they may have a curvature that coincides with a portion of a circle centered on the rotation center 426(1) so that the movement of the hinge during rotation is aligned with the rotation center 426(1). In the non-bending positions on the distal and proximal sides of the hinge, as seen in the tangential direction of the instrument, walls 446(1) and 444(1) partially overlap. The amount of overlap may be between 0.05 and 3 mm.

[0152] In use, the instrument 400 can be rotated in its tangential direction, for example, by applying a rotational force to the proximal end of the instrument 400. The instrument can then be positioned inside a channel (e.g., the intestine, blood vessel, or esophagus of an organism). Rotating the instrument within such a channel can induce friction between the channel wall and the instrument 400, thereby generating a torsional force on the instrument. Figure 9 and Figure 10 The hinge structure shown limits torsional response loss because, during rotation, wall 442(1) can be adjacent to wall 440(1), and wall 446(1) can be adjacent to wall 444(1), which will, to some extent, limit (or block) the possible rotational difference between the far and near sides of the hinge 407(1) shown in these figures. Thus, the hinge provides additional torsional stiffness due to walls 442(1), 440(1), 446(1), and 444(1).

[0153] Figure 10 A 3D view of tube 400 is shown, allowing for viewing of the interior of tube 400 as well. Therefore, in Figure 10 You can see Figure 9 More details of the first hinge 407(1) shown. Besides Figure 9 In addition to the first hinge shown, Figure 10 The second hinge 407(2) is shown, which is connected to... Figure 9 The hinges shown are identical, but the second hinge is rotated 90 degrees tangentially, thus allowing the entire hinge structure to bend in all directions, as will be clear to those skilled in the art. Figure 10 In, such as Figure 9 The various features of the first hinge 407(1) shown are indicated by the same reference numerals. Figure 10 The features of the second hinge 407(2) shown are indicated by the same reference numerals, but with the indication “(2)” instead of “(1)”.

[0154] Now, we will explain in detail... Figure 9 The features of the first hinge 407(1) are not (fully) visible. For the second hinge 407(2), this explanation will not be repeated, but it is the same except that "(1)" is changed to "(2)". Figure 10 As shown, the first hinge 407(1) has tangential slit portions 424a(1), 424b(1) and tangential slit portions 416a(1), 416b(1). The tangential slit portions 424a(1), 424b(1) have end portions 423(1) and 415(1). The tangential slit portions 424a(1), 424b(1) extend from end portion 423(1) to end portion 415(1), and partially surround the tube in the tangential direction H (see Figure 9 The tangential slit portions 416a(1), 416b(1) have an end 421(1) and an end 417(1). The tangential slit portions 416a(1), 416b(1) extend from the end 421(1) to the end 417(1), and partially surround the tube in the tangential direction G (see Figure 9 The tangential directions H and G are opposite directions. Ends 423(1) and 421(1) are located in the same plane perpendicular to the aforementioned central axis 29, on which ends 409(1) and 411(1) are located. Ends 423(1) and 421(1) are arranged to face each other.

[0155] End 423(1) coincides with the center of longitudinal slit 452(1), and end 421(1) coincides with the center of longitudinal slit 448(1), both of which extend longitudinally along the tube 400, thus defining the longitudinal side of the longitudinal bridge 450(1).

[0156] Similar to longitudinal slits 406(1) and 408(1), longitudinal slits 452(1) and 448(1) can both bend in opposite directions, such that longitudinal bridge 450(1) has a minimum width at a position that can be located at the center of the total length of longitudinal bridge 450(1). t .width t The length LB3 of slit 452(1) can be between 0.3 and 4 mm. The length LB4 of slit 448(1) can be between 0.3 and 4 mm. The length LB3 can be equal to the length LB4. Furthermore, all lengths LB1, LB2, LB3, and LB4 can be equal. The shape of slit 452(1) can coincide with a portion of the third circle CB3 having a third radius of 0.5-10 mm. The shape of slit 448(1) can coincide with a portion of the fourth circle CB4 having a fourth radius of 0.5-10 mm. The radius of the fourth circle CB4 can be equal to the radius of the third circle CB3. Furthermore, all radii of circles CB1, CB2, CB3, and CB4 can be equal. Here is the width. t The values ​​provided for the lengths LB3 and LB4, and the radii for CB3 and CB4, are applicable to tubular instruments with radii between 1 and 15 mm and wall thicknesses between 0.08 and 2 mm.

[0157] Therefore, compared to the case where the longitudinal bridge 450(1) has an equal width along its entire length, the longitudinal bridge 450(1) has a better center of rotation 458(1) at its center (the portion of the tube 400 located on the opposite side of the longitudinal direction of the bridge 450(1) can bend around this center of rotation), thus providing more accurate movement for the instrument.

[0158] Tangential slit portions 424a(1) and 424b(1) are located at longitudinally offset positions and are respectively connected at opposite ends of a longitudinal channel 429(1) that extends in the longitudinal direction of the instrument 400 to form a tangential shoulder structure. The sidewalls of the longitudinal channel 429(1) are defined by walls 454(1) and 456(1) that extend in the longitudinal direction of the instrument between the tangential slit portions 424a(1) and 424b(1). In an embodiment, walls 454(1) and 456(1) are straight. However, they may have a curvature that coincides with a portion of a circle centered on the rotation center 458(1) of the longitudinal bridge 450(1) so that the movement of the hinge during bending is aligned with the rotation center 458(1). In the non-bending positions on the distal and proximal sides of the hinge 407(1), as seen in the tangential direction of the instrument, walls 454(1) and 456(1) partially overlap. The overlap can be between 0.05 and 3 mm.

[0159] Tangential slit portions 416a(1) and 416b(1) are located at longitudinally offset positions and are respectively connected at opposite ends of a longitudinal channel 431(1) extending in the longitudinal direction of the instrument 400 to form a tangential shoulder structure. The sidewalls of the longitudinal channel 431(1) are defined by walls 462(1) and 464(1) extending in the longitudinal direction of the instrument between the tangential slit portions 416a(1) and 416b(1). In an embodiment, walls 462(1) and 464(1) are straight. However, they may have a curvature that coincides with a portion of a circle centered on a rotation center 458(1) so that the movement of the hinge during bending is aligned with the rotation center 458(1). In the non-bending positions on the two opposite sides of the hinge, as seen in the tangential direction of the instrument, walls 462(1) and 464(1) partially overlap. The amount of overlap may be between 0.05 and 3 mm.

[0160] As described above, in use, the instrument 400 can be rotated in its tangential direction, for example, by applying a rotational force to the proximal end of the instrument. The instrument can then be positioned inside a channel (e.g., the intestine, blood vessel, or esophagus of an organism). Rotating the instrument within such a channel can induce friction between the channel wall and the instrument, thereby generating a torsional force on the instrument. Figure 9 and Figure 10The hinge structure shown is better able to withstand increased torsional forces because, during rotation, wall 454(1) can be adjacent to wall 456(1), and wall 462(1) can be adjacent to wall 464(1), which will, to a certain extent, limit (or block) any possible rotational differences between the far and near sides of the hinges shown in these figures. Therefore, the hinge structure shown in these figures provides additional torsional stiffness due to walls 454(1), 456(1), 462(1), and 464(1).

[0161] In this embodiment, the tangential directions G and H lie in the plane perpendicular to the central axis of the tube 400. However, direction G may form an angle with this plane. The tangential direction H may also form an angle with this plane. These angles may be between -10° and +10°, more preferably between -8° and +8°. They may have the same value.

[0162] The longitudinal bridges 404(1) and 450(1) are preferably located on the tube 400 at positions that are circumferentially rotated 180 degrees away from each other, thereby allowing the tube 400 to bend around a virtual line passing through the rotation centers 426(1) and 458(1).

[0163] like Figure 9 and Figure 10 As shown, tangential slit portions 410b(1) and tangential slit portions 416b(1) overlap circumferentially, i.e., as seen in the longitudinal direction, a portion of tangential slit portion 410b(1) is positioned adjacent to a portion of tangential slit portion 416b(1), however, these portions are not joined to each other. A tangential bridge 403(1) exists between these portions of tangential slit portions 410b(1) and tangential slit portion 416b(1). The ends of the tangential bridge 403(1) are attached to the distal and proximal sides of the hinge 407(1), respectively. In an embodiment, the tangential bridge 403(1) has a constant width BW(1) (viewed in the longitudinal direction of the instrument). This width can be 0.05-0.3 mm. The length of the tangential bridge 403(1) can be a value between 20% and 45% of the tube circumference.

[0164] For example Figure 10As shown, tangential slit portions 418b(1) and tangential slit portions 424b(1) overlap circumferentially, i.e., as seen in the longitudinal direction, a portion of tangential slit portion 418b(1) is positioned adjacent to a portion of tangential slit portion 424b(1), however, these portions do not engage with each other. A tangential bridge 405(1) exists between these portions of tangential slit portions 418b(1) and tangential slit portion 424b(1). The ends of the tangential bridge 405(1) are attached to the distal and proximal sides of the hinge 407(1), respectively. In an embodiment, the tangential bridge 405(1) has a constant width BW(2) (viewed in the longitudinal direction of the instrument). This width can be 0.05-0.3 mm and can be the same as the width of the tangential bridge 403(1). The length of the tangential bridge 405(1) can be a value between 20% and 45% of the tube circumference. The lengths of tangential bridges 403(1) and 405(1) can be equal.

[0165] Although the longitudinal bridges 404(j) and 450(j) have been shown here as straight bridges, other forms may also be used, including, for example, S-shaped, Z-shaped or square waveforms, as shown in WO 2018067004.

[0166] Figure 11 An embodiment with three adjacent hinges is shown. More than three may exist. They are identical, and their features are indicated by indicator marks (1), (2), and (3), respectively. They are all arranged with the same tangential orientation, such that the entire hinge structure can be bent only in one plane (i.e., a plane perpendicular to the virtual line passing through the rotation centers 426(j) and 458(j) (j = 1, 2, ..., J).

[0167] Reference Figures 9 to 11 In the illustrated embodiment, if a laser is used, the channels defined by sidewalls 442(j) / 440(j), 446(j) / 444(j), 454(j) / 456(j), and 462(j) / 464(j) have a certain width defined by, for example, the width of a laser beam used to create all the slit patterns in tube 400. The width of these channels defines the maximum tangential clearance between adjacent sides of each hinge as the hinges rotate relative to each other in the tangential direction. It is desirable to keep this width as small as possible to reduce this clearance. Figure 12A , Figure 12B and Figure 12C This shows how to reduce the width of these channels.

[0168] In addition to the following, Figure 12A and Figure 9Similarly, when a slit pattern is formed in tube 400, the opposing sidewalls 442(1) and 440(1) are still attached to each other by means of the breaking element 480(1). Likewise, when a slit pattern is formed in tube 400, the opposing sidewalls 446(1) and 444(1) are still attached to each other by means of the breaking element 482(1). Figure 12B An example of a fracture element 482(1) in an enlarged shape is shown.

[0169] For example, the manufacturing process of creating the slit pattern by laser cutting gives the fracture element 482(1) a wider portion 484(1) and a smaller portion 488(1). Here, the wider portion 484(1) is attached to the sidewall 446(1), and the smaller portion 488(1) is attached to the sidewall 444(1), while the wider portion 484(1) is attached to the smaller portion 488(1). The first reason for manufacturing such a fracture element 482(1) is to maintain the different opposing portions of the tubular element 400 separated by slits that are still attached to each other, which makes the maneuverability of the tube 400 easier, for example, when it must be inserted into another tube or when another tube must be inserted into it. However, the second reason is that such a fracture element can be used to reduce the clearance between these opposing portions.

[0170] When the sidewalls are manufactured by, for example, cutting longitudinal channels 427(1) between sidewalls 446(1) and 444(1) with a laser beam, they will have a minimum distance caused by the width of the laser beam. w1 Without applying the fracture element 482(1) as explained here, this minimum distance occurs when opposite sides of the hinge rotate relative to each other in the tangential direction. w1 The clearance between sidewalls 446(1) and 444(1) will be limited.

[0171] When the hinge is forced to bend during use, causing the two opposite sides of the hinge to rotate around the rotation center 426(1), 458(1), the opposite sidewalls 446(1), 444(1) will be forced to move in opposite longitudinal directions. Figure 12B As shown, sidewall 446(1) can be subjected to force F2 Forced to move in the first longitudinal direction, and the sidewall 444(1) can be subjected to force F1 Forced to move in the opposite second longitudinal direction. The fracture element 482(1) is designed such that when these forces... F1 and F2 Above a certain threshold force, the smaller portion 488(1) will break, while the wider portion 484(1) will remain intact, and under force... F1 and F2Under the action of these forces, the hinge material attached to the wider portion 484(1) undergoes only elastic deformation but not plastic deformation, and the hinge material attached to the smaller portion 488(1) also undergoes only elastic deformation but not plastic deformation. Similarly, the wider portion 484(1) can undergo only elastic deformation but not plastic deformation through these forces, but this is not necessary.

[0172] Assume the length of the smaller portion 488(1) in the tangential direction of the instrument is w2 <w1 After the smaller portion 488(1) has broken, the wider portion 484(1) is disconnected from the sidewall 444(1), and can be connected by making the tube 400 toward the sidewall 444(1) along the maximum value. w2 The distance is tangentially rotated to force the wider section. This reduces the maximum clearance between sidewalls 446(1) and 444(1) to w2 .

[0173] Methods for manufacturing such fracture elements (and examples of their shapes) have been disclosed and explained in the applicant's WO 2016 / 089202. Fracture elements for manufacturing fracture elements that can be used to reduce clearance between adjacent parts of a tube separated by a slit can be found in the applicant's WO 2020 / 080938. Clearance-reducing fracture elements as disclosed in these applications can also be used.

[0174] The detailed explanation provided here for fracture element 482(1) also applies to fracture element 480(1). Furthermore, similar or identical clearance-reducing fracture elements can be applied between all opposing sidewalls 454(j) / 456(j) and 462(j) / 464(j).

[0175] Figure 12C It shows Figure 12B The alternative fracture element 490(1) to the fracture element 482(1).

[0176] like Figure 12C As shown, the sidewall 444(1) is divided into two parts: a first sidewall portion 444a(1) located in the tangential extension of the tangential slit 418a(1) and a second sidewall portion 444b(1) defining the longitudinal channel 427(1) between the tangential slits 418a(1) and 418b(1). The tangential distance between the second sidewall portion 444b(1) and the sidewall 446(1) is measured by the width. w1 Indicator. Width w1 Depending on the manufacturing method used, such as the size of the laser beam, the tangential distance between the second sidewall portion 444a(1) and the sidewall 446(1) is expressed as the width. w3 Instructions, in which w3 It can be as small as 0 mm. Width w1 >w3 During the manufacture of tube 400, a small fracture element or melt element 490(1) is maintained between the transition region between the first sidewall portion 444a(1) and the second sidewall portion 444b(1).

[0177] When element 490(1) is implemented as a fracture element, the fracture element will break by bending hinge 407(1) with a certain predetermined bending force. For this purpose, fracture element 490(1) is designed such that when the bending force (using a predetermined bending force) is applied, the fracture element will break. F1 and F2 (Illustratively indicating) Above a certain threshold force, the reaction force caused by the bending force inside the fracture element will cause the fracture element 490(1) to fracture, while the material of the sidewalls to which they are attached will remain intact, because this material can only deform elastically and not plastically. Fracture can also be caused by fatigue, i.e., by bending the hinge 407(1) multiple times with a force less than the threshold force but strong enough to eventually cause the fracture element 490(1) to fracture. This method induces a small tension in the material of the tube 400 attached to the fracture element 490(1).

[0178] When element 490(1) is implemented as a molten element, this molten element will be destroyed later in the manufacturing process by melting. For example, a tube 400 with hinge 407(1) is inserted into the interior of another tube, which has a hole in its structure aligned with the corresponding molten element. An energy beam (e.g., a laser beam) is then directed through such a hole to the molten element 490(1) with such energy that it destroys the molten element but does not destroy or barely destroys the sidewalls to which the molten element is attached.

[0179] A fracture element (like fracture element 490(1)) can be applied between all the opposing sidewalls 440(j) / 442(j), 454(j) / 456(j), and 462(j) / 464(j). If so, there is no reduction in tangential clearance after all these fracture elements have broken or been destroyed by melting, and all hinges 407(j) are not bent (the tube 400 is 100% straight). However, in practice, invasive instruments can be inserted into curved channels most of the time, such as in the human body, resulting in many (if not most) hinges 407(j) being more or less bent. In the bent state, at least some of the first sidewall portions 444a(1) (and their equivalents at corresponding other locations) will move relative to the sidewall 446(1) (and their corresponding equivalents at other locations), and the actual clearance will decrease from w1 Reduce to w3 .

[0180] The tubes of invasive instruments can have a circular cross-section. However, these tubes can also have other suitable cross-sections. For example, they can have an oval, elliptical, or rectangular cross-section. These tubes can be formed using suitable biocompatible polymer materials, such as polyurethane, polyethylene, polypropylene, or other biocompatible polymers. These tubes can also be made from any other suitable material and / or in any other suitable manner. Other suitable materials may include stainless steel, cobalt-chromium, shape memory alloys such as Nitinol®, plastics, polymers, composites, or other curable materials.

[0181] Circumferential slits, longitudinal slits, and other slits can be made using any known material removal technique (such as photochemical etching, deep pressing, or chip removal), however, they are preferably made by laser or waterjet cutting. All slits open to both the outside and inside of the tube.

[0182] Longitudinal slits, circumferential slits, and U-shaped slits can have any suitable length and width as required by the intended application. The longitudinal slits, circumferential slits, and U-shaped slits of the intermediate tube can have the same or different lengths and / or widths.

[0183] Preferably, their length is between 25% and 50% of the outer circumference of the tubular member, more preferably between 30% and 45%, and most preferably between 35% and 40%. The circumferential slits can have any suitable width. Circumferential slits of the same tubular member can have the same width or different widths. Circumferential slits can be narrower near their endpoints and wider in their central portion.

[0184] Longitudinal slits and angled slits can also have any suitable length and width depending on the needs of the intended application. Longitudinal slits and angled slits of tubular members can have the same or different lengths and / or widths.

[0185] The bending and torsional fidelity along the length of the tubular member can be varied by changing the hardness grade of the material used to mold different sections. Furthermore, the flexibility of the tubular member can be altered by changing the size and location of the circumferential, longitudinal, and inclined slits and / or by changing the angle between the circumferential slit and the radial circumference.

[0186] The tube 400 can have one of the following cross-sections: circular, oval, elliptical, or rectangular.

[0187] The tube 400 may be made at least in part from at least one of the following groups of materials: Biocompatible polymer materials, including polyurethane, Polyethylene or polypropylene, Stainless steel, Cobalt and chromium Shape memory alloys, such as Nitinol®, plastic, polymer, Composite materials, or Other curable materials.

[0188] In this embodiment, the cutting pattern of hinge 407(j) is obtained by a material removal technique applied to the wall of tube 400, including at least one of photochemical etching, deep pressing, chip cutting, laser cutting, or water jet cutting. The material removal method may be a laser beam that melts and evaporates the material, or a water jet cutting beam, and this beam may have a width of 0.01 to 2.00 mm, more typically between 0.015 and 0.04 mm in this application.

[0189] The wall thickness of the tube depends on its application. For medical applications, the wall thickness can range from 0.03 to 2.0 mm, preferably 0.03 to 1.0 mm, more preferably 0.05 to 0.5 mm, and most preferably 0.08 to 0.4 mm. The diameter of the tube depends on its application. For medical applications, the diameter can range from 0.5 to 20 mm, preferably 0.5 to 10 mm, and more preferably 0.5 to 6 mm. The radial clearance between adjacent tubes can range from 0.01 to 0.3 mm.

[0190] refer to Figures 9 to 12C The features of the present invention explained can be summarized as follows.

[0191] The invention described in these figures relates to a tube comprising a hinge structure including one or more hinges (407(j), j = 1, 2, ..., J), each hinge (407(j) including a first cut pattern and a second cut pattern in the tube (400), the first cut pattern and the second cut pattern being located between the proximal and distal sides of the hinge (407(j)). The first cutting pattern defines A first longitudinal bridge (404(j)) is located at a first position, extends in the longitudinal direction of the tube (400), and connects the proximal side and the distal side of the hinge. A first tangential slit (410a(j), 410b(j)) extends from the first longitudinal bridge (404(j)) along a first tangential direction (E) of the tube (400). The first tangential slit includes two first tangential slit portions (410a(j), 410b(j)) located at longitudinally offset positions and respectively connected to opposite ends of a first channel (425(j)). The first channel has a first longitudinally extending wall (440(j)) and a second longitudinally extending wall (442(j)) opposite to the first longitudinally extending wall (440(j)) to prevent tangential rotation of the proximal side of the hinge relative to the distal side of the hinge. A second tangential slit (418a(j), 418b(j)) extends from the first longitudinal bridge (404(j)) along a second tangential direction (F) of the tube (400), the first tangential direction and the second tangential direction being opposite directions. The second tangential slit includes two second tangential slit portions (418a(j), 418b(j)) located at longitudinally offset positions and respectively connected to opposite ends of a second channel (427(j)). The second channel has a third longitudinally extending wall (444(j)) and a fourth longitudinally extending wall (446(j)) opposite to the third longitudinally extending wall (444(j)) to prevent tangential rotation of the proximal side of the hinge relative to the distal side of the hinge. The second cutting pattern defines A second longitudinal bridge (450(j)) is located at a second position, extends in the longitudinal direction of the tube (400), and connects the proximal and distal sides of the hinge. This second position is rotated 180 degrees relative to the first position. A third tangential slit (424a(j), 424b(j)) extends from the second longitudinal bridge (450(j)) along the first tangential direction (E) of the tube (400). The third tangential slit includes two third tangential slit portions (424a(j), 424b(j)) located at longitudinally offset positions and respectively connected to opposite ends of a third channel (429(j)). The third channel has a fifth longitudinal extension wall (454(j)) and a sixth longitudinal extension wall (456(j)) opposite to the fifth longitudinal extension wall (454(j)) to prevent tangential rotation of the proximal side of the hinge relative to the distal side of the hinge. A fourth tangential slit (416a(j), 416b(j)) extends from the second longitudinal bridge (450(j)) along the second tangential direction (F) of the tube (400). The fourth tangential slit includes two fourth tangential slit portions (416a(j), 416b(j)) located at longitudinally offset positions and respectively connected to opposite ends of a fourth channel (431(j)). The fourth channel has a seventh longitudinal extension wall (462(j)) and an eighth longitudinal extension wall (444(j)) opposite to the seventh longitudinal extension wall (462(j)) to block tangential rotation of the proximal side of the hinge relative to the distal side of the hinge.

[0192] The first longitudinal bridge (404(j)) may have a first rotation center (426(j)) and the second longitudinal bridge (450(j)) may have a second rotation center (458(j)), each hinge (407(j)) being able to bend around a virtual line passing through the first rotation center (426(j)) and the second rotation center (458(j)), each of the first longitudinal extension wall (440(j)), the second longitudinal extension wall (442(j)), the third longitudinal extension wall (444(j)) and the fourth longitudinal extension wall (446(j)) being formed as part of a corresponding circle whose center is located at the first rotation center (426(j)), and each of the fifth longitudinal extension wall (454(j)), the sixth longitudinal extension wall (456(j)), the seventh longitudinal extension wall (462(j)) and the eighth longitudinal extension wall (444(j)) being formed as part of a corresponding circle whose center is located at the second rotation center (458(j)).

[0193] The first cutting pattern may have two longitudinal slits (406(j), 408(j)) that extend in the longitudinal direction and form two longitudinal sides of the first longitudinal bridge (404(j)), and the second cutting pattern may have two additional longitudinal slits (448(j), 452(j)) that extend in the longitudinal direction and form two longitudinal sides of the second longitudinal bridge (450(j)).

[0194] The two longitudinal slits (406(j), 408(j)) may be curved, such that the first longitudinal bridge (404(j)) has a first width that gradually increases toward its end.

[0195] These two additional longitudinal slits (448(j), 452(j)) may be curved, such that the second longitudinal bridge (404(j)) has a second width that gradually increases toward its ends.

[0196] The first tangential slit (410a(j), 410b(j)) can extend from the center (409(j)) of one of the two longitudinal slits (406(j), 408(j)), and the second tangential slit (418a(j), 418b(j)) can extend from the center (411(j)) of the other longitudinal slit (406(j), 408(j)).

[0197] The third tangential slit (424a(j), 424b(j)) can extend from the center (423(j)) of one of the two other longitudinal slits (448(j), 452(j)), and the fourth tangential slit (416a(j), 416b(j)) extends from the center (421(j)) of the other of the two other longitudinal slits (448(j), 452(j)).

[0198] One of the two first tangential slit portions (410a(j), 410b(j)) and one of the two fourth tangential slit portions (416a(j), 416b(j)) may at least partially overlap tangentially to form a first tangential bridge (403(j)) between them, one end of which is attached to the proximal side of the hinge and the other end is attached to the distal side of the hinge.

[0199] One of the two second tangential slit portions (418a(j), 418b(j)) and one of the two third tangential slit portions (424a(j), 424b(j)) may at least partially overlap tangentially to form a second tangential bridge (405(j)) between them, one end of which is attached to the proximal side of the hinge and the other end is attached to the distal side of the hinge.

[0200] The two first tangential slit portions (410a(j), 410b(j)) and the two third tangential slit portions (424a(j), 424b(j)) can be oriented to form a first angle with a plane perpendicular to the central axis of the tube (400), the first angle being between -10° and +10°, more preferably between -8° and +8°.

[0201] The two second tangential slit portions (418a(j), 418b(j)) and the two fourth tangential slit portions (416a(j), 416b(j)) can be oriented to form a second angle with a plane perpendicular to the central axis of the tube (400), the second angle being between -10° and +10°, more preferably between -8° and +8°.

[0202] The tube may include at least one of the following features: The first longitudinal extension wall (440(j)) and the second longitudinal extension wall (442(j)) have multiple portions of a fractured first fracture element (480(j)) in order to reduce the clearance between them. The third longitudinal extension wall (444(j)) and the fourth longitudinal extension wall (446(j)) have multiple portions of a fractured second fracture element (482(j)) in order to reduce the clearance between them. The fifth longitudinal extension wall (454(j)) and the sixth longitudinal extension wall (456(j)) have multiple portions of a fractured third fracture element in order to reduce the clearance between them, or The seventh longitudinal extension wall (462(j)) and the eighth longitudinal extension wall (444(j)) have multiple sections of the fractured fourth fracture element in order to reduce the clearance between them.

[0203] General Instructions The examples and embodiments described herein are illustrative and not limiting of the invention. Those skilled in the art will be able to devise alternative embodiments without departing from the scope of the claims. Reference numerals placed in parentheses in the claims should not be construed as limiting the scope of the claims. Items described as separate entities in the claims or specification may be implemented as a single hardware item or multiple hardware items combining the features of the described items.

[0204] It should be understood that the present invention is limited only to the appended claims and their technical equivalents. In this document and its claims, the verb "comprising" and its variations are used in their non-limiting sense to mean including the items following the word, without excluding items not specifically mentioned. Furthermore, referring to an element by the indefinite article "a / an" does not preclude the possibility of more than one / an of that element, unless the context explicitly requires the presence of one and only one / an element. Therefore, the indefinite article "a / an" generally means "at least one / an".

Claims

1. A steerable device having a distally deflectable end portion (358) and a proximal bendable body portion (356) of the end portion (358), the steerable device comprising at least one tube (312) and at least one of an inner tube (330) within the at least one tube (312) or an outer tube (340) outside the at least one tube (312), one or more steering wires (16(i)) within the at least one tube (312), the at least one tube (312) comprising a deflectable end portion (358) The flexible body section (309) in the flexible body portion (356) includes a turning end section (301) and a flexible body section (309) in the flexible body portion (356). One or more steering wires (16(i)) helically rotate in at least a portion of the flexible body section (309) in the circumferential direction of the steerable device. The steerable device also includes one or more longitudinal force isolation elements (322(k)) in the at least one tube (312), the longitudinal force isolation elements (322(k)) being arranged parallel to the one or more steering wires (16(i)) in the flexible body section (309). The one or more longitudinal force isolation elements (322(k)) have distal and proximal ends and apply one of the following features: If the steerable device includes the outer tube (340), the distal end of each longitudinal force isolation element (322(k)) is attached to the outer tube (340) at the distal end of the body section (309), and the proximal end of each longitudinal force isolation element (322(k)) is attached to the outer tube (340) at the proximal end of the body section (309), or If the steerable device includes the inner tube (330), the distal end of each longitudinal force isolation element (322(k)) is attached to the inner tube (330) at the distal end of the body section (309), and the proximal end of each longitudinal force isolation element (322(k)) is attached to the inner tube (330) at the proximal end of the body section (309), or If the steerable device includes the inner tube (330) and the outer tube (340), the distal end of each longitudinal force isolation element (322(k)) is attached at the distal end of the body section (309) to at least one of the inner tube (330) or the outer tube (340), and the proximal end of each longitudinal force isolation element (322(k)) is attached at the proximal end of the body section (309) to at least one of the inner tube (330) or the outer tube (340).

2. The steerable device according to claim 1, wherein, The one or more steering wires (16(i)) are helically rotated 180 degrees in the circumferential direction of the steerable device in at least a portion of the flexible body section (309) to provide path length compensation due to the bending of the at least a portion of the flexible body section (309).

3. The steerable device according to claim 2, wherein, The one or more steering wires (16(i)) are helically rotated an equal number of 180 degrees in a certain number of portions of the flexible body section (309) in the circumferential direction of the steerable device to provide path length compensation due to bending of one or more of the portions of the flexible body section (309).

4. The steerable device according to any one of the preceding claims, wherein, The one or more steering wires (16(i)) rotate in a continuous spiral along the entire flexible body section (309).

5. The steerable device according to any one of claims 1 to 4, comprising a plurality of steering wires (16(i)) positioned equidistantly in parallel in the tangential direction of the at least one tube (312); and a plurality of longitudinal force isolation elements (322(k)) at least one of the longitudinal force isolation elements (322(k)) located between two adjacent steering wires (16(i), 16(i+1)).

6. The steerable device according to claim 5, wherein, Each longitudinal force isolation element (322(k)) is attached to a spacer (318(i)) configured to maintain two adjacent steering wires (16(i)) at a desired tangential distance, and If the steerable device includes the outer tube (340), then the distal end of each longitudinal force isolation element (322(k)) is attached to the outer tube (340) via the spacer (318(i)) and the attachment thereto, or If the steerable device includes the inner tube (330), then the distal end of each longitudinal force isolation element (322(k)) is attached to the inner tube (330) via the spacer (318(i)) and the attachment thereto, or If the steerable device includes the inner tube (330) and the outer tube (340), the distal end of each longitudinal force isolation element (322(k)) is attached to at least one of the inner tube (330) or the outer tube (340) via the spacer (318(i)).

7. The steerable device according to claim 5 or 6, wherein, A single longitudinal force isolation element (322(k)) is arranged between two adjacent steering wires (16(i), 16(i+1)) and at an equal distance from the two adjacent steering wires.

8. The steerable device according to claim 7, wherein, A pair of flexible spacers (320a(i), 320b(i)) are disposed between two adjacent steering wires (16(i), 16(i+1)) and near the spacer (318(i), wherein the first flexible spacer of the pair of flexible spacers (320a(i), 320b(i)) is located between the single longitudinal force isolation element (322(k)) and the first steering wire of the two adjacent steering wires (16(i), 16(i+1)), and the second flexible spacer of the pair of flexible spacers (320a(i), 320b(i)) is located between the single longitudinal force isolation element (322(k)) and the second steering wire of the two adjacent steering wires (16(i), 16(i+1)).

9. The steerable device according to any one of the preceding claims, wherein, At least one of these longitudinal force isolation elements (322(k)) is provided with a through hole (325), and a lip extends from the inner tube (330) or the outer tube (340) through each of these through holes (325), the lips and the through holes (325) being configured to block tangential movement of the longitudinal force isolation elements (322(k)) relative to the inner tube (330) or the outer tube (340), but to allow axial movement.

10. The steerable device according to any one of the preceding claims, wherein, The at least one tube (312) includes an annular end portion (314) at its distal end, to which one or more steering wires (16(i)) are attached.

11. The steerable device according to claim 10, wherein, The end section of the at least one tube (312) includes a spacer (316(i)) between every two adjacent turning wires (16(i), 16(i+1)), each spacer (316(i)) having a regular wave pattern, such as a square wave or a sinus wave pattern.

12. The steerable device according to any one of the preceding claims, wherein, The at least one tube (312) has one of a circular, oval, elliptical or rectangular cross section.

13. The steerable device according to any one of the preceding claims, wherein, The at least one tube (312) is made of at least one of the following materials: Biocompatible polymer materials, including polyurethane, Polyethylene or polypropylene, Stainless steel, Cobalt and chromium Shape memory alloys, such as Nitinol®, plastic, polymer, Composite materials, or Other curable materials.

14. The steerable device according to any one of the preceding claims, wherein, The one or more steering wires (16(i)) and the one or more longitudinal force isolation elements (322(k)) are generated by a material removal technique applied to the wall of the at least one tube (312), the material removal technique including at least one of photochemical etching, deep pressing, chip cutting, laser cutting or water cutting.

15. The steerable device according to any one of the preceding claims, comprising a Bowden cable section (355) located proximal to the proximal end of the body section (356) to further compensate for the path length differences of the steering wires (16(i)) and the force isolation element (322(k)).

16. An invasive instrument comprising a steerable device according to any one of the preceding claims, and a steering unit configured to operate the steering wires (16(i)) to deflect the deflectable end portion (358), wherein, This steering unit is one of the manually operable steering units or robot steering units.

17. A tube including a hinge structure, the hinge structure comprising one or more hinges (407(j), j = 1, 2, ..., J), each hinge (407(j) including a first cut pattern in the tube (400) and a second cut pattern in the tube (400), the first cut pattern and the second cut pattern being located between the hinge proximal side and the hinge distal side of the hinge (407(j)). The first cutting pattern defines A first longitudinal bridge (404(j)) is located at a first position, extends in the longitudinal direction of the tube (400), and connects the proximal side and the distal side of the hinge. A first tangential slit (410a(j), 410b(j)) extends from the first longitudinal bridge (404(j)) along a first tangential direction (E) of the tube (400). The first tangential slit includes two first tangential slit portions (410a(j), 410b(j)) located at longitudinally offset positions and respectively connected to opposite ends of a first channel (425(j)). The first channel has a first longitudinally extending wall (440(j)) and a second longitudinally extending wall (442(j)) opposite to the first longitudinally extending wall (440(j)) to prevent tangential rotation of the proximal side of the hinge relative to the distal side of the hinge. A second tangential slit (418a(j), 418b(j)) extends from the first longitudinal bridge (404(j)) along a second tangential direction (F) of the tube (400), the first tangential direction and the second tangential direction being opposite directions. The second tangential slit includes two second tangential slit portions (418a(j), 418b(j)) located at longitudinally offset positions and respectively connected to opposite ends of a second channel (427(j)). The second channel has a third longitudinally extending wall (444(j)) and a fourth longitudinally extending wall (446(j)) opposite to the third longitudinally extending wall (444(j)) to prevent tangential rotation of the proximal side of the hinge relative to the distal side of the hinge. The second cutting pattern defines A second longitudinal bridge (450(j)) is located at a second position, extends in the longitudinal direction of the tube (400), and connects the proximal and distal sides of the hinge. This second position is rotated 180 degrees relative to the first position. A third tangential slit (424a(j), 424b(j)) extends from the second longitudinal bridge (450(j)) along the first tangential direction (E) of the tube (400). The third tangential slit includes two third tangential slit portions (424a(j), 424b(j)) located at longitudinally offset positions and respectively connected to opposite ends of a third channel (429(j)). The third channel has a fifth longitudinal extension wall (454(j)) and a sixth longitudinal extension wall (456(j)) opposite to the fifth longitudinal extension wall (454(j)) to prevent tangential rotation of the proximal side of the hinge relative to the distal side of the hinge. A fourth tangential slit (416a(j), 416b(j)) extends from the second longitudinal bridge (450(j)) along the second tangential direction (F) of the tube (400). The fourth tangential slit includes two fourth tangential slit portions (416a(j), 416b(j)) located at longitudinally offset positions and respectively connected to opposite ends of a fourth channel (431(j)). The fourth channel has a seventh longitudinal extension wall (462(j)) and an eighth longitudinal extension wall (444(j)) opposite to the seventh longitudinal extension wall (462(j)) to block tangential rotation of the proximal side of the hinge relative to the distal side of the hinge.

18. The pipe according to claim 17, wherein, The first longitudinal bridge (404(j)) has a first rotation center (426(j)), and the second longitudinal bridge (450(j)) has a second rotation center (458(j)). Each hinge (407(j)) is capable of bending around a virtual line passing through the first rotation center (426(j)) and the second rotation center (458(j)). The first longitudinal extension wall (440(j)), the second longitudinal extension wall (442(j)), and the third longitudinal extension wall (444) Each of the fourth longitudinal extension wall (446(j)) and the fifth longitudinal extension wall (454(j)), the sixth longitudinal extension wall (456(j)), the seventh longitudinal extension wall (462(j)) and the eighth longitudinal extension wall (444(j)) is formed as part of a corresponding circle whose center is located at the first rotation center (426(j)), and each of the eighth longitudinal extension wall (454(j)), the sixth longitudinal extension wall (456(j)), the seventh longitudinal extension wall (462(j)) and the eighth longitudinal extension wall (444(j)) is formed as part of a corresponding circle whose center is located at the second rotation center (458(j)).

19. The tube according to claim 17 or 18, wherein, The first cutting pattern has two longitudinal slits (406(j), 408(j)) that extend in the longitudinal direction and form two longitudinal sides of the first longitudinal bridge (404(j)), and the second cutting pattern has two additional longitudinal slits (448(j), 452(j)) that extend in the longitudinal direction and form two longitudinal sides of the second longitudinal bridge (450(j)).

20. The pipe according to claim 19, wherein, The two longitudinal slits (406(j), 408(j)) are curved, such that the first longitudinal bridge (404(j)) has a first width that gradually increases toward its end.

21. The tube according to claim 19 or 20, wherein, The two additional longitudinal slits (448(j), 452(j)) are curved, such that the second longitudinal bridge (404(j)) has a second width that gradually increases toward its ends.

22. The pipe according to claim 19, 20 or 21, wherein, The first tangential slit (410a(j), 410b(j)) extends from the center (409(j)) of one of the two longitudinal slits (406(j), 408(j)), and the second tangential slit (418a(j), 418b(j)) extends from the center (411(j)) of the other longitudinal slit of the two longitudinal slits (406(j), 408(j)).

23. The pipe according to any one of claims 19 to 21, wherein, The third tangential slit (424a(j), 424b(j)) extends from the center (423(j)) of one of the two other longitudinal slits (448(j), 452(j)), and the fourth tangential slit (416a(j), 416b(j)) extends from the center (421(j)) of the other of the two other longitudinal slits (448(j), 452(j)).

24. The pipe according to any one of claims 17 to 23, wherein, One of the two first tangential slit portions (410a(j), 410b(j)) and one of the two fourth tangential slit portions (416a(j), 416b(j)) are at least partially tangentially overlapped to form a first tangential bridge (403(j)) between them, one end of which is attached to the proximal side of the hinge and the other end of which is attached to the distal side of the hinge.

25. The pipe according to any one of claims 17 to 24, wherein, One of the two second tangential slit portions (418a(j), 418b(j)) and one of the two third tangential slit portions (424a(j), 424b(j)) are at least partially tangentially overlapped to form a second tangential bridge (405(j)) between them, one end of which is attached to the proximal side of the hinge and the other end of which is attached to the distal side of the hinge.

26. The pipe according to any one of claims 17 to 25, wherein, The two first tangential slit portions (410a(j), 410b(j)) and the two third tangential slit portions (424a(j), 424b(j)) are oriented to form a first angle with a plane perpendicular to the central axis of the tube (400), the first angle being between -10° and +10°, more preferably between -8° and +8°.

27. The pipe according to any one of claims 17 to 26, wherein, The two second tangential slit portions (418a(j), 418b(j)) and the two fourth tangential slit portions (416a(j), 416b(j)) are oriented to form a second angle with a plane perpendicular to the central axis of the tube (400), the second angle being between -10° and +10°, more preferably between -8° and +8°.

28. The pipe according to any one of claims 17 to 27, wherein, The tube has one of the following cross-sections: circular, oval, elliptical, or rectangular.

29. The tube according to any one of claims 17 to 28, wherein the tube is made of at least one of the following materials: Biocompatible polymer materials, including polyurethane, Polyethylene or polypropylene, Stainless steel, Cobalt and chromium Shape memory alloys, such as Nitinol®, plastic, polymer, Composite materials, or Other curable materials.

30. The pipe according to any one of claims 17 to 29, wherein, The first and second cutting patterns are generated by a material removal technique, which includes at least one of photochemical etching, deep pressing, chip cutting, laser cutting, or waterjet cutting.

31. The pipe according to any one of claims 17 to 30, wherein, The two first tangential slit portions (410a(j), 410b(j)), the two second tangential slit portions (418a(j), 418b(j)), the two third tangential slit portions (424a(j), 424b(j)) and the two fourth tangential slit portions (416a(j), 416b(j)) have the same length, which is preferably between 25% and 50% of the outer circumference of the tube, more preferably between 30% and 45%, and most preferably between 35% and 40%.

32. The pipe according to any one of claims 17 to 31, wherein, The two first tangential slit portions (410a(j), 410b(j)) and the two second tangential slit portions (418a(j), 418b(j)) taper toward the first longitudinal bridge (404(j)) and toward its opposite end, and the two third tangential slit portions (424a(j), 424b(j)) and the two fourth tangential slit portions (416a(j), 416b(j)) taper toward the second longitudinal bridge (450(j)) and toward its opposite end.

33. The tube according to any one of claims 17 to 32, comprising at least one of the following features: The first longitudinal extension wall (440(j)) and the second longitudinal extension wall (442(j)) have multiple portions of a fractured first fracture element (480(j)) to reduce the clearance between them. The third longitudinal extension wall (444(j)) and the fourth longitudinal extension wall (446(j)) have multiple portions of a fractured second fracture element (482(j)) in order to reduce the clearance between them. The fifth longitudinal extension wall (454(j)) and the sixth longitudinal extension wall (456(j)) have multiple portions of a fractured third fracture element in order to reduce the clearance between them, or The seventh longitudinal extension wall (462(j)) and the eighth longitudinal extension wall (444(j)) have multiple portions of the fractured fourth fracture element in order to reduce the clearance between them.

34. A steerable invasive device comprising a tube according to any one of claims 17 to 33, and a steering unit configured to deflect a deflectable end portion.

35. The steerable invasive device according to claim 34, wherein, This steering unit is one of the manually operable steering units or robot steering units.

36. A steerable tube (312) comprising a deflectable end section (301) at a distal end and a bendable body section (309) proximal to the deflectable end section (301); one or more steering wires (16(i)) configured to deflect the deflectable end section (301) and helically rotate in a circumferential direction of the steerable device in at least a portion of the bendable body section (309); and one or more spacer wires (322s(k)) providing a tangential spacing function between a first portion and a second portion of the tube (312), the spacer wires (322s(k)) extending in at least the entire bendable body section (309) and helically rotating in the bendable body section (309) like the one or more steering wires (16(i)).

37. The steerable tube according to claim 36, wherein, The first part is at least one of the first control wire and the first steering wire (16(i)), and the second part is at least one of the second control wire and the second steering wire (16(i+1)).

38. The steerable tube according to claim 36 or 37, wherein, At least one of the one or more spacer wires (322s(k)) includes at least two sub-spacer wires (322s(k, 1), 322s(k, 2)).

39. The steerable tube according to claim 38, wherein, The at least two sub-spacer wires (322s(k, 1), 322s(k, 2)) are separated by at least one slot (325s) and at least one of one or more bridges (323s) or one or more spacer elements (327).

40. The steerable tube according to any one of claims 36 to 39, wherein, The one or more spacer wires (322s(k)) are provided with a path length compensation mechanism in at least one of the distal and proximal ends of the steerable tube to compensate for changes in path length in the bendable body section (309).

41. The steerable tube according to any one of claims 36 to 40, wherein, The first part, the second part, the one or more steering wires (16(i)) and the one or more spacer wires (322s(k)) are part of the steerable tube and are defined by the cutting pattern in the steerable tube.

42. A steerable device comprising at least one of a steerable tube according to any one of claims 36 to 41, and an inner tube (330) within the steerable tube (312) or an outer tube (340) outside the steerable tube (312).

43. The steerable device of claim 41, comprising a control unit configured for at least one of manual or robotic control of the one or more steering wires (16(i)).

44. The steerable device according to claim 41, 42 or 43, wherein, The one or more spacer wires (322s(k)) are attached at a single location to at least one of the inner tube (330) and the outer tube (340).

45. The steerable device according to any one of claims 41 to 44, wherein, At least one of the inner tube (330) inside the steerable tube (312) or the outer tube (340) outside the steerable tube (312) is provided with at least one lip (352), and at least one of the one or more spacer wires (322s(k)) includes at least two sub-spacer wires (322s(k, 1), 322s(k, 2)) separated by a slot (325), and the at least one lip (352) is bent into the slot (325).

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