Inner rod, manufacturing method and resectoscope

Abstract

The invention relates to an inner shaft for a working element of a resectoscope, having a distal end section and at least three spacer elements which are arranged on an outer surface of the inner shaft, the spacer elements being arranged in such a way that they are distributed in different positions in the region of the distal end section, the inner shaft can be guided and / or placed in a predetermined manner at a distance from the outer shaft at least in the distal end section within the outer shaft. The invention also relates to a method for manufacturing the inner rod and a resectoscope.

Description

Technical Field

[0001] The invention relates to an inner rod for an operating element of a resectoscope. In addition, the invention relates to a method for producing the inner rod, and to a resectoscope having an outer rod and an inner rod of this type. Background Art

[0002] Surgical instruments are used for various applications. For example, they can be used in the field of minimally invasive surgery and have surgical tools. Surgical instruments can be configured as resectoscopes and have working elements, which are configured, for example, for guiding surgical tools, such as electrodes.

[0003] Resectoscopes are known to be used in particular in urology or gynecology. Here, an operating element with an electrode can be introduced through the urethra into the surgical area in the patient's body. At the distal end (i.e., away from the user), the electrode has, for example, a cutting collar, with the aid of which tissue can be removed. The removed tissue can be removed again via an exit channel with the aid of a flushing fluid, which is guided to the surgical area via a flushing channel or an entry channel. The entry channel and the exit channel allow for continuous flushing, which simultaneously serves to keep the viewing window clear so that a perfect endoscopic field of view can always be achieved.

[0004] DE 10056 618 A1 describes a double-rod endoscope for continuous flushing, which has an inner rod and an outer rod, wherein the inner rod includes an entry channel in which the optical device is received, and the outer rod surrounds the inner rod and is configured with an exit channel. A carrier for an electric cutting ring adjustable in the axial direction is received in the inner rod. The inner rod and the outer rod are arranged in a manner that they can be displaced relative to each other.

[0005] In order to guide a tool, such as an electrode, a surgical instrument usually has a carriage which is supported in a displaceable manner along the longitudinal axis of the surgical instrument and is connected to the surgical tool. The carriage can be displaced by means of a handle or by an actuator operable via a robot interface.

[0006] When the electrode is placed in the working element, the cutting collar of the electrode can be displaced in the axial direction by the axial movement of the carriage, for example, to remove tissue. The electrode must be movable relative to the outer rod. Therefore, the working element with the electrode must be guided in a manner spaced apart from the outer rod.

[0007] In known embodiments, a spacer element is usually provided in the region of the handle, for example in the region of the electrode holder, which is arranged in a downwardly protruding manner at the working element and contacts the inner contour of the outer rod. The electrode at the distal end can be held spaced apart from the outer rod by this spacer element at the proximal end.

[0008] A disadvantage is that, during the axial displacement of the electrode, friction occurs due to the spacer element arranged at the proximal end, which is considered to be disruptive during the handling of the surgical instrument.

[0009] A further disadvantage is that the working element is supported in a region remote from the distal end at which the electrode is arranged. Therefore, a drop relative to the outer rod may occur over the length of the working element up to the electrode.

[0010] However, in order to ensure the required maneuverability in a safe and reliable manner, it is desirable to always be able to guide the electrode back into the inner rod. Summary of the invention

[0011] Against this background, it is an object of the invention to provide an improved support of the electrode relative to the inner rod or relative to the outer rod.

[0012] According to the invention, this object is achieved by an inner rod having the features of the following technical solution, a method having the features of the following technical solution and an electroresectoscope having the features of the following technical solution.

[0013] Therefore, it is stipulated that:

[0014] An inner rod for a working element of an electroresectoscope, comprising a distal end section and at least three spacer elements arranged on the outer surface of the inner rod, wherein the spacer elements are arranged in different positions distributed in the region of the distal end section so that the inner rod can be guided and / or placed within the outer rod at least in the distal end section in a predetermined manner and spaced apart from the outer rod.

[0015] A method for producing an inner rod for an operating element of a resectoscope, wherein the shape of the inner rod is produced by erosion.

[0016] A resectoscope has an outer shaft and an inner shaft, wherein the inner shaft is guided in the outer shaft in such a way that a lowering of a working tool, in particular an electrode, relative to the outer shaft is prevented by a spacing element in the region of a distal end section.

[0017] The invention is based on the finding that lowering of the electrode can be avoided by guiding the working element at the distal end of the surgical instrument.

[0018] The invention is based on the idea of ​​guiding the inner rod in the region of the distal end by means of at least two spacer elements which are in punctiform or linear contact with the outer rod.

[0019] The lowering of the electrode at the distal end can be avoided by the spacing element, because even if the electrode or the working element is displaced axially, the spacing between the inner rod and the outer rod can be adjusted and maintained directly by the spacing element in the region of the distal end section. Therefore, the working element is advantageously not arranged in a freely suspended manner in the region of the distal end, but is guided at the inner rod. Therefore, it can be ensured that it can be moved into the outer rod again when the electrode is displaced axially. Therefore, there is advantageously no risk that the removed electrode will not fall due to gravity to such an extent that it cannot be moved back. Therefore, the electrode can be moved into the outer rod without any problems at any time.

[0020] Furthermore, by guiding the working element at the inner rod, contact between the working element and the outer rod can be avoided, so that no friction that interferes with the working process occurs when the electrode is moved in and out. During the axial displacement of the working element, there is no friction resistance between the working element and the outer rod, because there is no direct contact between the two elements. More precisely, the working element is guided at the inner rod and is thus also kept spaced apart from the outer rod in the region of the distal end.

[0021] The inner rod can have different designs. For example, the inner rod can have a discontinuous cross section, wherein convex and / or concave arches can adjoin straight sections. In particular, the cross section is configured to be symmetrical in a plane or on an axis, so that the working element can be guided symmetrically at the cross section.

[0022] Preferably, the cross section has a relatively small wall thickness, in particular 0.09 to 0.20 mm, for example about 0.15 mm. The wall thickness can vary in the region of the cross section. Likewise, the inner rod can be configured with a constant cross section all around.

[0023] A spacing element can be understood as an element that protrudes from the outer surface of the inner rod. Thus, the inner rod can be guided in a manner spaced apart from the outer rod by means of the spacing element. In particular, the dimensions of at least two spacing elements are designed so that the inner rod can be spaced apart from the outer rod over the entire circumference. As a result, a circumferential exit channel can be formed between the inner rod and the outer rod. Since the spacing element does not extend over the entire length of the inner rod, the exit channel is only disturbed by the spacing element in a very short axial section, wherein the medium guided back diffuses in an unhindered manner in the axial direction before or after each spacing element.

[0024] The spacing element is preferably designed to be rounded, so that no damage occurs when it comes into contact with the outer rod.

[0025] The distal end section is preferably understood to be a region which is configured to be smaller than the entire length of the inner rod. Preferably, the distal end section adjoins the distal end of the inner rod.

[0026] Erosion processes are particularly suitable for thin wall thicknesses, such as those implemented in inner rods. Wall thicknesses between 0.09 and 0.2 mm can be considered thin wall thicknesses. In particular, wall thicknesses between 0.1 and 0.17 mm. In addition, very high precision can be achieved by spark cutting.

[0027] Advantageous embodiments and improvements will be apparent from the other subordinate technical solutions and from the description with reference to the figures of the drawings.

[0028] According to an advantageous embodiment, the spacer elements can be arranged at different circumferential positions on the outer surface of the inner rod, in particular at circumferential positions offset from each other by at least 90°, preferably by more than 100°. This allows the inner rod to be reliably held spaced apart from the outer rod in the circumference. Preferably, two spacer elements of this type are formed identically, so that the inner rod can be held symmetrically relative to the outer rod at least in a plane.

[0029] According to an advantageous embodiment, the spacer elements can be arranged in different positions along the longitudinal axis of the inner rod. For example, one spacer element can be arranged closer to the distal end than another spacer element. Likewise, the spacer elements can be shaped to have different axial lengths.

[0030] According to an advantageous embodiment, the spacer element can be constructed in one piece with the inner rod. The spacer element can be constructed, for example, as an arch with an internally open or hollow cross section. The spacer element can also be made of solid material.

[0031] According to an advantageous embodiment, at least one spacer element can be designed in a dome-shaped manner and at least one spacer element can be designed in a bead-shaped manner. In this case, the bead-shaped spacing element extends over a larger longitudinal section along the inner rod than the dome-shaped spacing element. Advantageously, the dome-shaped spacing element is formed by an arch. For example, the dome-shaped spacing element can be arranged closer to the distal end than the bead-shaped spacing element. In particular, an elongated shape oriented in the axial direction of the inner rod can be understood as a bead-shaped shape. It can be formed in a wedge-shaped cross section, for example with a cross section that is at least partially triangular, and / or formed in one piece with the inner rod.

[0032] According to an advantageous embodiment, two bead-shaped spacer elements can be provided which are opposite in cross section, wherein in particular the dome-shaped spacer element is arranged centrally relative thereto. Thus, the spacing between the inner rod and the outer rod can be reliably ensured in the circumferential direction.

[0033] According to an advantageous embodiment, the inner rod can be shaped in at least one region for contacting at least one working tool, wherein the working tool can be guided in a manner spaced apart from the outer rod due to the shape of the cross section at a predetermined position. Partial sections of the cross section of the inner rod can be understood as being particularly adapted to the region of the shape of the working element. The contact between the inner rod and the working element is preferably able to keep the working element spaced apart from the outer rod. For example, a receiving bracket for the working element can be formed by the shape of the inner rod in this region. The working element is preferably held in the receiving bracket in a non-displaceable manner. The working element is preferably held on the outside, i.e., on the outer surface, at the inner rod.

[0034] According to an advantageous embodiment, the inner rod can be formed with a working channel for guiding and / or fixing a working tool, which working channel is arranged within the cross section of the inner rod. It can be formed by one or two at least sectionally partially circular or hood-shaped elements. As a result, other working tools can be guided in a spaced manner relative to the outer rod, in particular held in a clamped manner.

[0035] According to an advantageous embodiment, the spacing element and the at least one region for contacting at least one working tool can be arranged adjacent to each other on the inner rod. As a result, the working element can be held outside the inner rod, i.e. at the outer surface, while the spacing element is likewise arranged at the outer surface of the inner rod. As a result, the diameter of the outer rod can be reduced and a surgical instrument with a very small diameter can be provided.

[0036] According to an advantageous embodiment, the outer surface can be configured in different circumferential regions to be sectionally concave and sectionally convex. Thus, a region for clamping or holding the working element can be formed and at the same time a relatively large inner surface for forming the access channel can be maintained.

[0037] According to an advantageous embodiment, the wall thickness of the inner shaft can be at least partially 0.1 mm to 0.2 mm, in particular about 0.15 mm. This makes it possible to provide a very fine surgical instrument.

[0038] In particular, the inner rod has a constant cross section over its length. Spacer elements are excluded, which are in particular arranged only in the region of the distal end section.

[0039] According to an advantageous embodiment of the method, at least one spacing element can be formed by an embossing process. The spacer element can be formed later on the already manufactured inner rod. In addition, weight and material can be saved.

[0040] Advantageously, the shape of the inner rod and the spacer element can be made by an additive manufacturing process, such as laser sintering, to achieve metal 3D printing.

[0041] According to an advantageous embodiment of the resectoscope, the working tool, in particular the electrode, can be positioned and guided in a contactless manner with respect to the outer rod, and in particular can be guided back after being pushed out. This is achieved by means of a spacing element in the region of the distal end section, wherein a lowering of the electrode or the working element at the distal end is avoided. In particular, the guiding of the working element by the geometry of the inner rod (i.e. the working element is supported on the inner rod) can prevent the electrode from lowering relative to the inner rod at the distal end.

[0042] The above-mentioned designs and improvements can be combined with each other arbitrarily when necessary. Other possible designs, improvements and implementations of the present invention also include combinations of features described before or after with reference to the embodiments of the present invention that are not explicitly mentioned. In particular, those skilled in the art will also add various aspects as improvements or supplements to the corresponding basic forms of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The invention is further explained below with reference to the exemplary embodiments given in the schematic representations of the accompanying drawings. It is shown therein:

[0044] Figure 1 A working element with electrodes in the prior art is shown;

[0045] Figure 2 shows a distal end section of an inner rod according to one embodiment;

[0046] Figure 3 shows a cross section of a distal end section of a surgical instrument;

[0047] Figure 4 A cross section of the distal end section of the inner rod is shown.

[0048] Any illustrations in the accompanying drawings should convey a further understanding of the embodiments of the present invention. They illustrate the embodiments and are used to explain the principles and concepts of the present invention in conjunction with the description. Other embodiments and many of the advantages mentioned can be derived by referring to the accompanying drawings. The elements in the drawings are not necessarily shown in proportion to each other.

[0049] In the figures of the drawings, identical, functionally identical and acting identically elements, features and components are provided with the same reference symbols unless otherwise indicated. DETAILED DESCRIPTION

[0050] Figure 1The working element 2' in the prior art is shown. A working tool 9' is arranged in the distal end section 5'. The working tool is constructed as an electrode 14'. The electrode 14' is guided in the electrode tube 15'. At the proximal end section opposite to the distal end section 5', an electrode clamp is arranged at the working element 2'. A spacing element 17' is provided at the bottom of the electrode clamp, which contacts the inner contour of the outer rod (not shown) when it is loaded into the surgical instrument. As a result, the working element 2' can be kept spaced apart from the outer rod, thereby avoiding contact between the electrode and the outer rod. Disadvantageously, when the electrode is axially displaced in the surgical instrument, friction occurs between the outer rod and the spacing element 17'. In addition, the electrode 14' and the working element 2' are arranged in the region of the distal end section 5 in a freely suspended manner. As a result, the electrode 14' may fall in an unintentional manner only due to gravity. As a result, it is not always possible to ensure that the electrode 14' is guided back into the outer rod.

[0051] Figure 2 The distal end section 5 of the inner rod 1 according to one embodiment is shown. Figure 1 In contrast to the embodiment of the present invention, at the distal end section 5, three spacing elements 6a to 6c are arranged at three different circumferential positions 7 on the outer surface of the inner rod 1. Each spacing element 6a to 6c is placed in a manner that is only slightly spaced apart from the distal end. Here, the spacing element 6a is closer to the distal end than the spacing element 6c. The other spacing elements 6b (at Figure 3 and Figure 4 ) is shaped in the same way as the spacing element 6c and is arranged in the same way.

[0052] In this embodiment, the spacer element 6a is arranged centrally in the upper region of the inner rod 1 and is dome-shaped. The spacer element 6a can be produced, for example, by a stamping process. The other visible spacer element 6c is formed in the shape of a weld bead along the longitudinal axis 8 of the inner rod 1. This can be produced, for example, by etching during the production of the inner rod 1.

[0053] The illustrated spacing elements 6a and 6c are arranged at the inner rod 1 in such a way that the inner rod 1 can be arranged spaced apart from the outer rod (not shown) at a distance around it. In this embodiment, the spacing element 6c is formed with a wedge-shaped cross section. All spacing elements 6a to 6c are configured to be rounded in the area of ​​contact with the outer rod, so that damage to the outer rod can be avoided.

[0054] Figure 3The cross section of the distal end section 5 of the surgical instrument is shown. The electrode 14 is guided in the electrode tube 15. The electrode tube 15 is held in the region 18 due to the cross-sectional shape of the inner rod 1, so that the electrode 14 and the electrode tube 15 can be prevented from falling at the distal end section 5, especially over the entire length of the working element 2. It can be ensured that the electrode 14 can be guided back into the outer rod 4 at any time. The working tool 9 is held, especially clamped, in the concave circumferential region 12 of the inner rod 1, while the spacers 6a to 6c are arranged at the convex circumferential region 13 or the straight circumferential region, respectively.

[0055] The spacer elements 6a to 6c are arranged at different circumferential positions 7a to 7c in a manner spaced apart from one another. The spacer elements 6a to 6c are in particular arranged in a manner offset from one another by at least 90°, preferably at least 100°.

[0056] It can be clearly seen in the cross-sectional illustration that the spacer elements 6a to 6c are arranged on the inner rod 1 adjacent to the electrode tube 15. Inner rod 1 can thereby be held spaced apart from outer rod 4 at the periphery, wherein at the same time the smallest possible diameter of outer rod 4 can be ensured.

[0057] exist Figure 3 In the embodiment, the optical element 16 is also held on the inner rod 1 by the shape of the inner rod 1. Here, the region 18 and the upper convex circumferential region 13 serve as clamping sections, see also Figure 2 Furthermore, the working tool 11 is held in the lower region of the inner rod 1 in a clamped manner by means of a cap-shaped element in the inner rod 1. This allows further working channels to be formed.

[0058] Figure 4 A cross section of the distal end section 5 of the inner rod 1 is shown. It can be seen that the spacing elements 6a to 6c are offset from each other by at least 90° around the circumference of the inner rod 1. The spacing between the spacing elements 6b and 6c is greater than the corresponding spacing from the spacing element 6a. In this embodiment, the inner rod 1 is also constructed to be symmetrical with respect to an axis (here a vertical axis). As a result, the working element with the electrode tube can be held or placed in the region 18 at the inner rod in a symmetrical manner.

[0059] An inlet channel 19 is formed in the interior of the inner rod 1. An outlet channel is formed between the inner rod 1 and the outer rod 4, see Figure 3 .

[0060] Although the present invention has been fully described above with reference to preferred embodiments, the present invention is not limited thereto but can be modified in various ways and manners.

[0061] For example, the number of spacer elements 6 may differ from the number shown. Furthermore, the spacer elements 6 may be arranged at different circumferential positions 7. Two or three dome-shaped spacer elements 6 are also conceivable. In another embodiment, all spacer elements 6, for example three or four spacer elements 6, may be configured in the form of a bead.

[0062] Furthermore, the spacer elements 6 can directly adjoin the distal end or all be arranged equidistantly relative to the distal end. It is only important that the at least two spacer elements 6 prevent the electrode from being lowered directly in the region of the distal end.

[0063] Description of Reference Numerals

[0064] 1Inner rod

[0065] 2 Working components

[0066] 3. Resectoscope

[0067] 4 outer rod

[0068] 5 Distal end section

[0069] 6 Spacer elements

[0070] 7 Circumferential Positions

[0071] 8 Longitudinal axis

[0072] 9 Work Tools

[0073] 10 working channels

[0074] 11Working Tools

[0075] 12 Concave circumferential area

[0076] 13 Convex circumferential area

[0077] 14 Electrodes

[0078] 15 Electrode tube

[0079] 16 Optical Components

[0080] 17 Spacer element at electrode clamp

[0081] 18 Regions

[0082] 19 Enter the passage

Claims

1. An inner rod (1) for a working element (2) of an electroresectoscope (3), comprising: a distal end section (5); and At least three spacer elements (6) are arranged on the outer surface of the inner rod (1), wherein the spacer elements (6) are arranged in a manner distributed in different positions in the region of the distal end section (5) so that the inner rod (1) can be guided and / or placed in a predetermined manner within the outer rod (4) at least in the distal end section (5) so as to be spaced apart from the outer rod (4).

2. The inner rod (1) according to claim 1, characterized in that: The spacer elements (6) are arranged at different circumferential positions (7) on the outer surface (7) of the inner rod (1), in particular at circumferential positions offset from each other by at least 90°, preferably by more than 100°.

3. An inner rod (1) according to any one of the preceding claims, characterized in that The spacing elements (6) are arranged in different positions along the longitudinal axis (8) of the inner rod (1).

4. An inner rod (1) according to any one of the preceding claims, characterized in that The spacer element (6) is constructed in one piece with the inner rod (1).

5. An inner rod (1) according to any one of the preceding claims, characterized in that At least one spacer element (6a) is configured in a dome-shaped manner and at least one spacer element (6b) is configured in a bead-shaped manner, wherein the bead-shaped spacer element (6b) extends over a larger longitudinal section along the inner rod (1) than the dome-shaped spacer element (6a).

6. The inner rod (1) according to claim 5, characterized in that: Two bead-shaped spacer elements (6b, 6c) are provided which are opposite each other in cross section, wherein the in particular dome-shaped spacer element (6a) is arranged centrally relative thereto.

7. An inner rod (1) according to any one of the preceding claims, characterized in that The inner rod (1) is shaped in at least one region (18) for contacting at least one working tool (9), wherein the working tool (9) can be guided in a spaced-apart manner from the outer rod (4) due to the cross-sectional shape at a predetermined position.

8. An inner rod (1) according to any one of the preceding claims, characterized in that The inner rod (1) is formed with a working channel (10) for guiding and / or fixing a working tool (11), and the working channel is arranged within the cross section of the inner rod (1).

9. The inner rod (1) according to claim 7 or 8, characterized in that: The spacing element (6) and the at least one region (18) for contacting at least one working tool (9) are arranged adjacent to one another on the inner rod (1).

10. An inner rod (1) according to any one of the preceding claims, characterized in that The outer surface (7) is designed to be concave in sections and convex in sections in different circumferential regions.

11. An inner rod (1) according to any one of the preceding claims, characterized in that The wall thickness of the inner rod (1) is at least partially 0.1 mm to 0.2 mm, in particular approximately 0.15 mm.

12. A method for producing an inner rod (1) for an operating element (2) of a resectoscope (3), the inner rod being in particular an inner rod (1) according to any one of the preceding claims, wherein the shape of the inner rod is produced by erosion.

13. The method according to claim 12, characterized in that At least one spacer element (6) is formed by an embossing process.

14. A resectoscope (3) comprising: an outer rod (4); an inner rod (1) according to any one of claims 1 to 11, wherein the inner rod (1) is guided in the outer rod (4) in such a manner that the lowering of the working tool (9), in particular the electrode (14), relative to the outer rod (4) is avoided by the spacing element (6) in the area of ​​the distal end section (5).

15. The resectoscope according to claim 14, characterized in that: The working tool (9), in particular the electrode (14), is positioned and guided in a contact-free manner with respect to the outer rod (4), in particular can be guided back after being pushed out.

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