LU103448B1

LU103448B1 - Flexible shaft and flexible endoscopic instrument

Info

Publication number: LU103448B1
Application number: LU103448A
Authority: LU
Inventors: Indrek Polluks
Original assignee: Storz Karl Se & Co Kg
Priority date: 2024-11-06
Filing date: 2024-11-06
Publication date: 2026-05-06
Also published as: WO2026099083A1

Abstract

The present invention provides a shaft (1) for a flexible endoscopic instrument, comprising: an shaft structure (2) having a distal end (3) and a proximal end (4), wherein the shaft structure (2) comprises a holding unit (5) for receiving and positionally securing at least two steering wires, wherein the holding unit (5) is arranged between the proximal end (4) and the distal end (3). Further, the present invention provides a flexible endoscopic instrument (100) comprising such a flexible shaft (1).

Description

2024P00096 LU _1-

LU103448

Flexible shaft and flexible endoscopic instrument

TECHNICAL FIELD

The present invention pertains to a flexible shaft for a flexible endoscopic instru- ment. Furthermore, the present invention pertains to a flexible endoscopic instru- ment with such a flexible shaft.

BACKGROUND

Surgical tube shaft instruments such as flexible endoscopic instruments are used for a variety of applications in medicine and technology. Such flexible endoscopic instruments comprise a flexible elongated shaft which is suitable for insertion into a cavity, such as an internal body cavity or a cavity of a technical object. As a rule, an endoscopic instrument lens is arranged at the tip of the endoscopic instrument shaft to generate an image of a scene in the observed cavity. To record and transmit the endoscopic image from the distal (i.e. far from the observer) to the proximal (i.e. close to the observer) end region of the endoscopic instrument, an ordered bundle of optical fibers running inside the shaft can be provided, for ex- ample, or an electronic image sensor, such as a CCD chip, which is arranged in the region of the distal end of the shaft and whose signals are transmitted to the proximal end region via electrical lines running inside the shaft. Since there is usu- ally not enough light in the observed cavity, a light guide system can also be ar- ranged inside the shaft to transport light to the distal end of the endoscopic instru- ment, where it is used to illuminate the cavity. Further, the endoscopic instrument shaft may include one or more working channels for passing endoscopic working instruments from the proximal to the distal end portion of the shaft for performing manipulations within the cavity.

Surgical tube shaft instruments are also known which comprise a flexible elongat- ed shaft which is also suitable for insertion into a cavity, such as an internal body cavity or a cavity of a technical object. Such a flexible endoscopic instrument can be used to carry out manipulations in the cavity and for this purpose can be de-

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LU103448 signed, for example, as a grasping instrument for grasping and manipulating tissue or objects in the cavity inside the body or in the cavity of a technical object. For this purpose, a tool is arranged at the distal end of the shaft, which can be operat- ed from the proximal end of the shaft via a transmission means running inside the shaft. Such a flexible endoscopic instrument usually does not have its own optics for recording an endoscopic image, but can be used in particular together with a flexible endoscopic instrument.

It is often desirable to be able to angle the distal end of the shaft, i.e. the tip of the endoscope or endoscopic instrument, in order to facilitate the insertion of the en- doscope or endoscopic instrument through a non-flexible endoscopic instrument through a non-rectilinear channel, to be able to move the tip within a cavity in a lateral direction and to be able to change the viewing direction of an optical system arranged in the endoscopic instrument tip or the working direction of a tool ar- ranged at the tip of the endoscopic instrument. For this purpose, the shaft has a controllable section, in particular a controllable end section, which can be actively angled by a desired amount in a desired direction and can be controlled for this purpose from the proximal end of the endoscopic instrument. The shaft for a flexi- ble endoscopic instrument need not itself have a tool and a transmission means, but can for example comprise a working channel into which a flexible endoscopic working instrument which cannot be actively angled and which has such a tool can be inserted up to the distal end of the shaft and possibly beyond, so that the flexi- ble working instrument can be angled with the aid of the shaft.

The flexible shaft is usually part of the flexible endoscope, which transfers the torque and force from a handle to a distal section. Since the flexible shaft is hollow it protects also the internal components, like the working channel, light/imager ca- bles, springs and/or push-pull wires. The vertebrae respectively flexible shaft is ac- tuated usually through lever, which is pulling the wire ropes or push-pull wires, re- spectively. In order to enable controllable articulation of a section of a shaft of a flexible endoscope, it is known to form the latter with a basic structure comprising individual segments which can be pivoted relative to one another and which can be actuated by the push-pull wires, like cable pulls or Bowden cables, guided in

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LU103448 the endoscope shaft. In particular, handwheels arranged on the endoscope handle are provided for actuation.

On urology field the vertebrae and the distal tip visibility under X-ray is helpful and in some applications essential.

For example, document US 2024/0008721 A1 describes an endoscope comprising a bending section body having hinges and a steering wire attached to a segment of the bending section body proximally of at least a distal-most hinge.

In document US 2005/0131279 A1 each segment of a controllable section of the endoscope shaft is pivotably mounted relative to the next or previous segment.

Four cables are provided for angling the shaft section or endoscope tip in ques- tion, which are guided from a proximally arranged control device to the endoscope tip. The cables run in the edge area of the segments and are each offset by 90° to one another with respect to a longitudinal axis, so that the endoscope tip can be steered in a desired direction by rolling up the corresponding cables in the control device.

However, each cable is guided in a tiny through-hole running along the shaft such that manufacturing and in particular assembling of the flexible shaft is difficult and/or lengthy. Current one-piece injection molded shafts on the market usually have complex molds to make round cable guide holes through the whole shaft.

DISCLOSURE OF THE INVENTION

It is an object of the present invention to provide a flexible shaft, which can simplify an assembling process of endoscopic instrument and tolerate torque loads.

According to the invention, this problem is solved by a flexible shaft for a flexible endoscopic instrument with the features of claim 1 and/or by a flexible endoscopic instrument with the features of claim 14.

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LU103448

According to a first aspect of the invention, a flexible shaft for a flexible endoscop- ic instrument is provided. The flexible shaft comprises a shaft structure having a distal end and a proximal end, wherein the shaft structure comprises a holding unit for receiving and positionally securing at least two steering wires. The holding unit is arranged between the proximal end and the distal end.

According to a second aspect of the invention, a flexible endoscopic instrument is provided. The flexible endoscopic instrument comprises a flexible shaft according to the first aspect of the invention and at least two steering wires, which are re- ceived and positionally secured in the holding unit.

A fundamental concept of the invention is to provide a flexible endoscope work- ing vertebrae or shaft, respectively, that is cheaper and quicker to manufacture and also tolerates torque loads.

A particular advantage in the solution according to an aspect of the invention is that the flexible shaft can be applicable for injection molding or similar manufac- turing processes.

A further advantage of the present invention is that a manufacturing of the flexible shaft can be more simplified and/or longer lasting.

The working channel can be inserted into a tubular shaft of the flexible endoscop- icinstrument. The working channel is mounted or guided at least at an end, in particular an proximal end, of a rod in the flexible endoscopic instrument. In par- ticular, the rod is mounted or guided in the tubular shaft in such a way that the working channel cannot move or rotate axially relative to the tube shaft.

If the flexible endoscopic instrument is to be operated by a user such as a sur- geon, the flexible endoscopic instrument comprises a handle as a grip for the us- er. The operating interface then transmits a force or torque, which is applied by

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LU103448 the user to the handle via a suitable actuation (e.g. movable handle leg), to a force transmission element for example.

If the flexible endoscopic instrument is to be connected to a robot, the flexible endoscopic instrument comprises a corresponding connection interface for the robot, which can apply an axial force or torque to the force transmission element via the operating interface.

Advantageous embodiments and further developments emerge from the descrip- tion with reference to the figures.

According to some embodiments of the invention, the holding unit is arranged sec- tionwise at two opposing lateral inner sides of the shaft structure or integrated sec- tionwise in a wall of the shaft structure.

According to some further embodiments of the invention, the shaft structure is configured at least sectionwise to be articulatable at least in one plain.

According to some further embodiments of the invention, the shaft structure is configured as one piece, which is manufactured by an injection molding process.

Hence, a manufacturing of the flexible shaft can be quick and easy.

For example, the flexible shaft is configured as a single use flexible endoscope vertebrae. In particular, the flexible shaft comprises an one-piece single use flex- ible endoscope articulation on the distal end.

Optionally, the shaft structure can be elastically deformable at least in an area of the slot.

According to some further embodiments of the invention, the shaft structure is made of a polymer material including a X-ray fluorescence additive for X-ray visi- bility. For example, the X-ray fluorescence additive comprises Bismuth subcar- bonate, Bismuth oxychloride, Barium sulfate and/or tungsten. The X-ray fluores-

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LU103448 cence additive can be added to the polymer material in a powder form. The poly- mer material can comprise or be made of polyurethane, polyimide, polyether ether ketone or the like.

According to some further embodiments of the invention, the X-ray fluorescence additive has a mass percentage in the polymer material of about 60 % or less, in particular of about 40 % or about 20 %. Thus, mechanical properties of the shaft structure would not be affected drastically.

According to some further embodiments of the invention, the shaft structure com- prises a plurality of cutouts, which are arranged in series along a longitudinal axis between the proximal end and the distal end, wherein the holding unit is arranged between two of the plurality of cutouts. In particular, the holding unit is arranged between two adjacent cutouts of the plurality of cutouts. Each of the plurality of cutouts can extend in a circumferential direction of the shaft structure.

According to some further embodiments of the invention, the flexible shaft further comprises a multilumen tube, which is arranged inside the shaft structure, wherein the multilumen tube interacts with the holding unit and is configured for positionally securing the at least two steering wires in the holding unit. The multilumen tube can be manufactured by an extrusion process. Moreover, the multilumen tube and the shaft structure can have a press fit with each other.

For example, the multilumen tube has a first lumen respectively cavity for receiv-

Ing a working channel and a second lumen for receiving an optical image device.

In particular, the second lumen respectively cavity can include a recess extending between the proximal end and the distal end. Hence, the second lumen can be loaded with internal components like the optical image device during an assembly of the flexible shaft. In other words, the multilumen tube can provide an opened contour for flexprints.

According to some further embodiments of the invention, the holding unit compris- es a plurality of retaining members, which are arranged between the proximal end

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LU103448 and the distal end in an alignment. For example, the plurality of retaining members can be arranged at a lateral inner side of the shaft structure or be integrated in a wall of the shaft structure.

According to some further embodiments of the invention, each of the plurality of retaining members is configured as a cylindrically shaped opening, wherein the cylindrically shaped opening is configured for receiving a steering wire.

According to some further embodiments of the invention, the holding unit consists of a first retaining member that is arranged at one of the two opposing lateral inner sides and of a second retaining member that is arranged at the other of the two opposing lateral inner sides. For example, the first and/or the second retaining member can be arranged at the lateral inner side of the shaft structure or be inte- grated in a wall of the shaft structure. Furthermore, the first and/or the second re- taining member can be configured as a cylindrically shaped opening, wherein the cylindrically shaped opening is configured for receiving a steering wire.

According to some further embodiments of the invention, the holding unit is at- tached to a bendable protrusion, which is shaped and configured to be insertable into the shaft structure by bending the protrusion such that the holding unit is pushed into the shaft structure. For example, the holding unit can be attached to a free end portion of the bendable protrusion. In an open state the bendable protru- sion protrudes from the shaft structure, wherein in a closed state the holding unit can be pushed into a corresponding slot and the bendable protrusion forms a part of a shell of the shaft structure.

According to some further embodiments of the invention, the shaft structure com- prises a foldable hinge device, which extends at least sectionwise from the distal end to the proximal end, wherein the shaft structure is formed by at least two parts that are coupled together by the foldable hinge such that the at least two parts are pivotable relative to each other. As a result, a manufacturing of the flexible shaft, in particular a manufacturing of an injection mold, can be simpler and/or longer lasting. For closing the shaft structure the at least two parts can be materially

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LU103448 bonded together, in particular materially bonded by ultrasonic welding. For exam- ple, a contact area of the at least two parts can be materially bonded together.

Furthermore, the holding unit can be arranged at the contact area. Thus, the steering wire can be placed in the holding unit before the shaft structure is closed.

After closing the shaft structure the steering wire is positionally secured.

Additionally, the shaft structure can comprise a through-opening, which is config- ured for receiving a working channel and/or an optical image device, wherein the through-opening can extend through the shaft structure from the proximal end to the distal end.

According to some further embodiments of the invention, the flexible endoscopic instrument further comprises a distal tip, which is materially bonded to the distal end of the shaft structure and coupled to the at least two steering wires. For ex- ample, the distal tip can be bonded to the distal end by an ultraviolet adhesive.

The distal tip can comprise a tool respectively accessory, which can be moved by the axial force or torque transmitted via the at least two steering wires or push-pull wires, respectively, inside and opposite the shaft structure. The tool can be con- figured as a clamp, plier, tweezer, gripper, scissors and the like. In particular, the tool can also be configured to be operated monopolar or bipolar, for example to cut or cauterize tissue and the like.

Optionally, the flexible endoscopic instrument can comprise an operating inter- face, which is arranged at the proximal end of the flexible shaft and configured to operate the flexible shaft.

The operating interface and/or the flexible endoscopic instrument can be made of a plastic material. For example, the flexible endoscopic instrument can be com- pletely made of a plastic material, in particular when the flexible endoscopic in- strument is intended to use only once.

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LU103448

Optionally, the shaft structure comprises a plurality of shaft sections arranged in series. The plurality of shaft sections arranged in series correspond to an active bending section of the flexible endoscopic instrument.

The plurality of shaft sections can be connected by an integrated connecting bar, which connects adjacent shaft sections such that they are articulatable in one plain. For example, each shaft section can be configured as a vertebral member, which is coupled to the adjacent vertebral member such that pivoting of the verte- bral member relative to the adjacent vertebral member in a radial axis is provided.

For example, the shaft structure can comprise a circular or oval shape. Thereby, the shaft structure can have a constant diameter. A cross section of the shaft structure can have an oval shape in order to reduce intra renal pressure and/or to provide natrium chloride circulation during operation, in particular on urology field.

Moreover, the flexible endoscopic instrument can further comprise a working channel for communicating fluids or medical tools from the operating interface to the distal end of the shaft.

In other words, the present invention can provide a flexible endoscope vertebrae design with one piece polymer design. Furthermore, the X-ray fluorescence addi- tive can be used on the plastic respectively polymer material, most likely the per- centage of the additive is below 40% to not affect mechanical properties drastical- ly. In some embodiments the multilumen tube can be used, where a cavity is open to load internal components during an assembly, like cable or flex PCB. In some embodiments the flexible endoscope vertebrae design can have only one support- ing guidance respectively holding unit for the wire rope respectively push-pull wire, wherein an elasticity of the vertebrae or flexible shaft, respectively, can avoid a snaking problem. In some embodiments the flexible endoscope vertebrae design can have pushed in elements for wire ropes. In some embodiments the flexible endoscope vertebrae design can be manufactured from two pieces, what makes manufacturing of injection molds simpler and/or long lasting.

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LU103448

The above embodiments and further developments can be combined with one an- other arbitrarily, as far as appropriate. Further possible configurations, develop- ments and implementations of the invention are also combinations of features of the invention described above or below for the exemplary embodiments that are not explicitly cited. In particular, a person skilled in the art will also add individual aspects as improvements or additions to the respective basic form of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is explained more specifically below on the basis of the exemplary embodiments indicated in the schematic figures, in which:

Fig. 1 shows an embodiment of a handheld steerable flexible endoscopic instru- ment according to an embodiment of the invention in an overall view;

Fig. 2 shows a perspective view of a flexible shaft for a flexible endoscopic in- strument according to a further embodiment of the invention;

Fig. 3 shows a side view of the flexible shaft of Fig. 2, wherein a cut view A-A of the flexible shaft is illustrated:

Fig. 4 shows a detail view of the holding unit of the flexible shaft of Fig. 2 accord- ing to a further embodiment of the invention:

Fig. 5 shows a perspective view of a flexible shaft for a flexible endoscopic in- strument according to a further embodiment of the invention, wherein the holding unit is attached to a bendable protrusion;

Fig. 6 shows a detail view of the holding unit of the flexible shaft of Fig. 5;

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LU103448

Fig. 7 shows a perspective view of a flexible shaft for a flexible endoscopic in- strument according to a further embodiment of the invention comprising a folda- ble hinge device;

Fig. 8 shows a detail view of the holding unit of the flexible shaft of Fig. 7;

Fig. 9 shows a perspective view of a flexible shaft for a flexible endoscopic in- strument according to a further embodiment of the invention comprising a multi- lumen tube;

Fig. 10 shows a side view of the flexible shaft of Fig. 9, wherein a cut view

B-B of the flexible shaft is illustrated; and

Fig. 11 shows a detail view of the holding unit of the flexible shaft of Fig. 9.

The accompanying figures are intended to convey a further understanding of the embodiments of the invention. They illustrate embodiments and are used in con- junction with the description to explain principles and concepts of the invention.

Other embodiments and many of the cited advantages emerge in light of the drawings. The elements of the drawings are not necessarily shown to scale in relation to one another. Direction-indicating terminology such as for example "at the top", "at the bottom", "on the left", "on the right", "above", "below", "horizontal- ly", "vertically", "at the front", "at the rear" and similar statements are merely used for explanatory purposes and do not serve to restrict the generality to specific configurations as shown in the figures.

In the figures of the drawing, elements, features and components that are the same, have the same function and have the same effect are each provided with the same reference signs - unless explained otherwise.

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LU103448

DETAILED DESCRIPTION OF DRAWINGS

Fig. 1 shows an embodiment of a handheld steerable flexible endoscopic instru- ment 100 in an overall view.

As shown schematically in Fig. 1, the flexible endoscopic instrument 100 typically comprises a handpiece 101 and a flexible shaft 1, the handpiece 101 being at- tached to a proximal end of the flexible shaft 1. The handpiece 101 can have an outer housing 102 made of a plastic and/or metallic material. On a lower side of the housing 102 a first hand wheel 103 and a second hand wheel 104 are ar- ranged for controlling a deflection of a steerable section 1a of the flexible shaft 1, as is described below. Typically the first and the second hand wheel 103, 104 are arranged coaxially, and at an exterior side of the second hand wheel 104 a knob 105 for controlling a deflection brake relating to the second hand wheel 104 is provided. Further, the handpiece 101 may exhibit a multiplicity of control buttons 106 for controlling various functions of the flexible endoscopic instrument 100, such as for controlling the imaging and/or illumination system and/or irrigation and suction pumps, for example. The handpiece 101 may be connectable to an exter- nal video unit or a video monitor via connector 107 and to an external light source via light cable 108. Moreover, an instrument port 109 may be provided for insert- ing endoscopic instruments to be advanced through one or more respective chan- nels to a distal end of the flexible shaft 1 for manipulating tissue or other objects within a cavity into which the flexible shaft 1 can be inserted.

At its distal end the flexible shaft 1 comprises a steerable section 1a. The steera- ble section 1a may form a distal end section of the flexible shaft 1 or, as shown in

Fig. 1, may carry a distal end cap 11, which may accommodate an imaging optics and an electronic image sensor for providing an endoscopic image of a cavity into which the flexible shaft 1 is inserted. The image signal generated by the image sensor may be transmitted via electric cables extending through the shaft 1 and the handpiece 101 to the connector 107 for being processed and displayed by an external video unit. The flexible shaft 1 in total is flexible to an extent to be ad- vanced through an endoscopic access or a hollow organ towards a cavity to be

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LU103448 observed, being capable of adapting to a curved shape of the access or the organ.

The steerable section 1a, on the other hand, is capable of being flexed actively by turning the hand wheels 103, 104. To this end the steerable section 1a comprises an inner structure of a plurality of shaft sections, thus being deflectable or articu- latable in one or more planes. The plurality of shaft sections can be covered by a flexible tube to form a smooth outer surface, the flexible shaft 1 in total having a uniform cross-sectional shape and diameter.

For controlling the deflection of the plurality of shaft sections two counteracting control wires (not shown in Fig. 1) are provided extending on opposite sides within the plurality of shaft sections, by a longitudinal movement of which the steerable section 1a can be bent to one or the other side, as indicated symbolically in Fig. 1.

The control wires extend along the shaft 1 and are connected at their proximal ends to a deflection control mechanism arranged within the handpiece 101, which can be operated by a user by turning the hand wheels 103, 104 for deflecting the steerable section 1a. In the exemplary embodiment shown, the steerable section can be bent or articulated within a first plane that corresponds to the plane of the drawing, a deflection angle being controllable by rotating the first hand wheel 103.

Further, the steerable section 1a can be bent in a second plane perpendicular to the first plane and perpendicular to the plane of the drawing, a corresponding de- flection angle being controllable by rotating the second hand wheel 104.

The flexible shaft 1 exemplarily comprises a shaft structure having a distal end 3 and a proximal end 4. The shaft structure comprises a holding unit for receiving and positionally securing at least two steering wires. The holding unit is arranged between the proximal end 4 and the distal end 3.

The at least two steering wires are received and positionally secured in the hold- ing unit.

Fig. 2 shows a perspective view of a flexible shaft 1 for a flexible endoscopic in- strument according to a further embodiment of the invention. Fig. 3 shows a side view of the flexible shaft 1 of Fig. 2, wherein a cut view A-A of the flexible shaft 1 is illustrated.

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LU103448

The flexible shaft 1 comprises a shaft structure 2 having a distal end 3 and a prox- imal end 4, wherein the shaft structure 2 comprises a holding unit 5 for receiving and positionally securing at least two steering wires. The holding unit 5 is ar- ranged between the proximal end 4 and the distal end 3.

Furthermore, the holding unit 5 can be arranged sectionwise at two opposing lat- eral inner sides of the shaft structure 2 or integrated sectionwise in a wall of the shaft structure 2.

The shaft structure 2 can be configured at least sectionwise to be articulatable at least in one plain. For example, the shaft structure 2 may comprise a plurality of cutouts 6, which are arranged in series along a longitudinal axis X between the proximal end 4 and the distal end 3, wherein the holding unit 5 is arranged be- tween two of the plurality of cutouts 6. In particular, the holding unit 5 is arranged between two adjacent cutouts 6 of the plurality of cutouts 6 as it is exemplarily il- lustrated in Fig. 4. Each of the plurality of cutouts 6 can extend in a circumferential direction of the shaft structure 2. The circumferential direction can be provided around the longitudinal axis X.

Moreover, the shaft structure 2 can be configured as one piece, which is manufac- tured by an injection molding process. Hence, a manufacturing of the flexible shaft 1 can be quick and easy.

The shaft structure 2 can be made of a polymer material including a X-ray fluores- cence additive for X-ray visibility. For example, the X-ray fluorescence additive comprises Bismuth subcarbonate, Bismuth oxychloride, Barium sulfate and/or tungsten. The X-ray fluorescence additive can be added to the polymer material in a powder form. The polymer material can comprise or be made of polyurethane, polyimide, polyether ether ketone or the like. Preferably, the X-ray fluorescence additive can have a mass percentage in the polymer material of about 60 % or less, in particular of about 40 % or about 20 %.

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LU103448

Here, the holding unit 5 can comprise a plurality of retaining members 5-i, which are arranged between the proximal end 4 and the distal end 3 in an alignment. For example, the plurality of retaining members 5-i can be arranged at a lateral inner side of the shaft structure 2 or be integrated in a wall of the shaft structure 2. More specifically, each of the plurality of retaining members 5-i can be configured as a cylindrically shaped opening, wherein the cylindrically shaped opening can be configured for receiving a steering wire.

Further, the holding unit 5 here exemplarily consists of a first retaining member that is arranged at one of the two opposing lateral inner sides and of a second re- taining member that is arranged at the other of the two opposing lateral inner sides. For example, the first and/or the second retaining member can be arranged at the lateral inner side of the shaft structure 2 or be integrated in a wall of the shaft structure 2. Furthermore, the first and/or the second retaining member can be configured as a cylindrically shaped opening, wherein the cylindrically shaped opening is configured for receiving a steering wire.

Optionally, the shaft structure 2 can comprise a through-opening 10, which is con- figured for receiving a working channel and/or an optical image device, wherein the through-opening 10 can extend through the shaft structure from the proximal end 4 to the distal end 3.

Fig. 4 shows a detail view of the holding unit 5 of the flexible shaft 1 of Fig. 2 ac- cording to a further embodiment of the invention.

In Fig. 4, it is shown that the holding unit 5 can be arranged sectionwise at two opposing lateral inner sides of the shaft structure 2. The holding unit 5 can be con- figured as a bridge at the lateral inner side of the shaft structure. Furthermore, the shaft structure 2 may comprise a recess on a lateral outer side in a region of the holding unit 5.

Optionally, the shaft structure 2 can comprise a groove, which is arranged at the inner lateral side. The groove can support the positionally securing of the steering

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LU103448 wire. Moreover, the groove can extend along the longitudinal axis X. For example, the holding unit 5 configured as a bridge can bridge the groove.

Fig. 5 shows a perspective view of a flexible shaft 1 for a flexible endoscopic in- strument according to a further embodiment of the invention, wherein the holding unit 5 is attached to a bendable protrusion.

The shaft structure 2 can be made of a polymer material including a X-ray fluores- cence additive for X-ray visibility. For example, the X-ray fluorescence additive comprises Bismuth subcarbonate, Bismuth oxychloride, Barium sulfate and/or

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LU103448 tungsten. The X-ray fluorescence additive can be added to the polymer material in a powder form. The polymer material can comprise or be made of polyurethane, polyimide, polyether ether ketone or the like. Preferably, the X-ray fluorescence additive can have a mass percentage in the polymer material of about 60 % or less, in particular of about 40 % or about 20 %.

Further, the holding unit 5 is here exemplarily attached to a bendable protrusion 8, which is shaped and configured to be insertable into the shaft structure 2 by bend- ing the protrusion 8 such that the holding unit 5 is pushed into the shaft structure 2. For example, the holding unit 5 can be attached to a free end portion of the bendable protrusion 8.

In an open state the bendable protrusion 8 protrudes from the shaft structure 2, wherein in a closed state the holding unit 5 can be pushed into a corresponding slot and the bendable protrusion 8 forms a part of a shell of the shaft structure 2.

Fig. 6 shows a detail view of the holding unit 5 of the flexible shaft 1 of Fig. 5.

More specifically, the shaft structure 2 is illustrated in the closed state. That means, the holding unit 5 is pushed into the corresponding slot. Thereby, the bendable protrusion 8 forms a part of the shell of the shaft structure 2.

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Fig. 7 shows a perspective view of a flexible shaft 1 for a flexible endoscopic in- strument according to a further embodiment of the invention comprising a foldable hinge device. In Fig. 8, a detail view of the holding unit 5 of the flexible shaft 1 of

Fig. 7 is shown.

The shaft structure 2 can be made of a polymer material including a X-ray fluores- cence additive for X-ray visibility. For example, the X-ray fluorescence additive comprises Bismuth subcarbonate, Bismuth oxychloride, Barium sulfate and/or tungsten. The X-ray fluorescence additive can be added to the polymer material in

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LU103448 a powder form. The polymer material can comprise or be made of polyurethane, polyimide, polyether ether ketone or the like. Preferably, the X-ray fluorescence additive can have a mass percentage in the polymer material of about 60 % or less, in particular of about 40 % or about 20 %.

Further, the shaft structure 2 here exemplarily comprises a foldable hinge device 9, which extends at least sectionwise from the distal end 3 to the proximal end 4, wherein the shaft structure 2 is formed by at least two parts 2a, 2b that are cou- pled together by the foldable hinge 9 such that the at least two parts 2a, 2b are pivotable relative to each other. As a result, a manufacturing of the flexible shaft 1, in particular a manufacturing of an injection mold, can be simpler and/or longer lasting.

For closing the shaft structure 2 the at least two parts 2a, 2b can be materially bonded together, in particular materially bonded by ultrasonic welding. For exam- ple, a contact area of the at least two parts 2a, 2b can be materially bonded to- gether. Furthermore, the holding unit 5 can be arranged at the contact area. Thus, the steering wire can be placed in the holding unit 5 before the shaft structure 2 is closed. After closing the shaft structure 2 the steering wire is positionally secured.

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Fig. 9 shows a perspective view of a flexible shaft 1 for a flexible endoscopic in- strument according to a further embodiment of the invention comprising a multilu- men tube. Furthermore, Fig. 10 shows a side view of the flexible shaft of Fig. 9, wherein a cut view B-B of the flexible shaft 1 is illustrated. Fig. 11 shows a detail view of the holding unit 5 of the flexible shaft 1 of Fig. 9.

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Further, the flexible shaft 1 may comprise a multilumen tube 7 as it is illustrated in

Fig. 9. The multilumen tube 7 is arranged inside the shaft structure 2, wherein the multilumen tube 7 interacts with the holding unit 5 and is configured for positionally securing the at least two steering wires in the holding unit 5. The multilumen tube 7 can be manufactured by an extrusion process.

Moreover, the multilumen tube 7 and the shaft structure 2 can have a press fit with each other. For example, the multilumen tube 7 has a first lumen 7a respectively cavity for receiving a working channel and a second lumen 7b for receiving an op- tical image device. In particular, the second lumen 7b respectively cavity can in- clude a recess extending between the proximal end 4 and the distal end 3. Hence, the second lumen 7b can be loaded with internal components like the optical im- age device during an assembly of the flexible shaft 1. In other words, the multilu- men tube 7 can provide an opened contour for flexprints.

In the detailed description above, various features have been combined in one or more examples in order to improve the rigorousness of the illustration. However, it should be clear in this case that the above description is of merely illustrative but in no way restrictive nature. It serves to cover all alternatives, modifications and equivalents of the various features and exemplary embodiments. Many other examples will be immediately and directly clear to a person skilled in the art on the basis of his knowledge in the art in consideration of the above description.

The exemplary embodiments have been chosen and described in order to be able to present the principles underlying the invention and their application possi- bilities in practice in the best possible way. As a result, those skilled in the art can optimally modify and utilize the invention and its various exemplary embodiments with regard to the intended purpose of use. In the claims and the description, the

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LU103448 terms "including" and "having" are used as neutral linguistic concepts for the cor- responding terms "comprising". Furthermore, use of the terms "a", "an" and "one" shall not in principle exclude the plurality of features and components described in this way.

While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without de- parting from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s). In addition, in this disclosure, the terms “comprise” or “comprising” do not exclude other elements or steps, the terms “a” or “one” do not exclude a plural number, and the term “or” means either or both. Furthermore, characteristics or steps which have been de- scribed may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or appli- cation from which it claims benefit or priority.

2024P00096 LU _23-

LU103448

REFERENCE LIST

1 flexible shaft 2 shaft structure 2a, 2b at least one part of the shaft structure 3 distal end 4 proximal end 5 holding unit 5-i plurality of retaining members 6 plurality of cutouts 7 multilumen tube 7a first lumen 7b second lumen 8 bendable protrusion 9 foldable hinge device 10 recess 100 flexible endoscopic instrument 102 operating interface 104 tool or accessory 105 handle 106 movable handle limb 107 accessory interface

Claims

2024P00096 LU —24— LU103448 CLAIMS

1. Flexible shaft (1) for a flexible endoscopic instrument (100), comprising: a shaft structure (2) having a distal end (3) and a proximal end (4), wherein the shaft structure (2) comprises a holding unit (5) for receiving and positionally securing at least two steering wires, wherein the holding unit (5) is arranged be- tween the proximal end (4) and the distal end (3).

2. Flexible shaft (1) according to claim 1, characterized in that the holding unit (5) is arranged sectionwise at two opposing lateral inner sides of the shaft structure (2) or integrated sectionwise in a wall of the shaft structure (2).

3. Flexible shaft (1) according to claim 1 or 2, characterized in that the shaft structure (2) is configured at least sectionwise to be articulatable at least in one plain.

4. Flexible shaft (1) according to one of the preceding claims, characterized in that the shaft structure (2) is configured as one piece, which is manufactured by an injection molding process.

5. Flexible shaft (1) according to one of the preceding claims, characterized in that the shaft structure (2) is made of a polymer material includ- ing a X-ray fluorescence additive for X-ray visibility.

6. Flexible shaft (1) according to claim 5, characterized in that the X-ray fluorescence additive has a mass percentage in the polymer material of about 60 % or less, in particular of about 40 % or about 20

%.

7. Flexible shaft (1) according to one of the preceding claims, characterized in that the shaft structure (2) comprises a plurality of cutouts (6), which are arranged in series along a longitudinal axis (X) between the proximal

2024P00096 LU _25- LU103448 end (4) and the distal end (3), wherein the holding unit (5) is arranged between two of the plurality of cutouts (6).

8. Flexible shaft (1) according to one of the preceding claims, further comprising a multilumen tube (7), which is arranged inside the shaft struc- ture (2), wherein the multilumen tube (7) interacts with the holding unit (5) and is configured for positionally securing the at least two steering wires in the holding unit (5).

9. Flexible shaft (1) according to one of the claims 1 to 7, characterized in that the holding unit (5) comprises a plurality of retaining mem- bers (5-1), which are arranged between the proximal end (4) and the distal end (3) in an alignment.

10. Flexible shaft (1) according to claim 9, characterized in that each of the plurality of retaining members (5-1) is configured as a cylindrically shaped opening, wherein the cylindrically shaped opening is con- figured for receiving a steering wire.

11. Flexible shaft (1) according to claim 2, characterized in that the holding unit (5) consists of a first retaining member that is arranged at one of the two opposing lateral inner sides and of a second retain- ing member that is arranged at the other of the two opposing lateral inner sides.

12. Flexible shaft (1) according to one of the claims 1 to 7, 9 or 10, characterized in that the holding unit (5) is attached to a bendable protrusion (8), which is shaped and configured to be insertable into the shaft structure (2) by bending the protrusion (8) such that the holding unit (5) is pushed into the shaft structure (2).

13. Flexible shaft (1) according to one of the claims 1 to 7, 9 or 10, characterized in that the shaft structure (2) comprises a foldable hinge device (9), which extends at least sectionwise from the distal end (3) to the proximal end (4),

2024P00096 LU —2 6— LU103448 wherein the shaft structure (2) is formed by at least two parts (2a, 2b) that are coupled together by the foldable hinge device (9) such that the at least two parts (2a, 2b) are pivotable relative to each other.

14. Flexible endoscopic instrument (100), comprising: a flexible shaft (1) according to one of the preceding claims; and at least two steering wires, which are received and positionally secured in the holding unit (5).

15. Flexible endoscopic instrument (100) according to claim 14, further comprising a distal tip, which is materially bonded to the distal end (3) of the shaft structure (2) and coupled to the at least two steering wires.