SK5914Y1 - Cannula and cannula device for implanting an implant - Google Patents

Abstract

Cannula (1) having a proximal end (12) which is provided for insertion into tissue in which an implant is to be placed, a distal end (14) which is provided for connection to a cannula holder (30), channel (16) for an implant, between the distal end and the proximal end is arranged the lateral opening (22) to the channel (16).Cannula device is equipped by the cannula holder (30) and the cannula (10), wherein the cannula holder (30) is connected with the cannula by force, shape or material jointing.

Description

Technical field

The technical solution concerns a cannula and a cannula device for implant implantation.

BACKGROUND OF THE INVENTION

Implant devices are preferably used in the treatment of cancer patients, and serve to deliver the drug subcutaneously into the cancer patient. To this end, rods are made of biodegradable plastic as implants. The implant imparts an active ingredient in the patient's body which, for example, causes a reduction in testosterone and thus blocks tumor growth. We break down the implant by means of hydrolysis based on the natural water regime in the human body. Typically, the drug delivery period in a patient's body lasts more than about four weeks.

An implant device is used to insert the implant into the human body. This typically consists of three functional parts, a cannula that contains the implant, a cannula holder that can be permanently connected to the cannula, and an applicator that applies the implant from the needle to the patient's tissue. The cannula holder and the cannula together form a cannula device.

The implant is inserted into the proximal opening of a rod-shaped cannula, according to the prior art with tweezers and a piston rod. Subsequently, a plastic solution that fixes the implant rods is applied to the implant through the proximal opening of the cannula. This plastic solution can be introduced into the cannula using a dispensing pipette as a drop in a predetermined amount. The droplet then proximally sits in front of the implant rod and holds both the inner wall of the cannula and the implant rod and cures at room temperature. It thus secures the implant rods against falling out of the cannula.

If such an implant rod is to be applied, it is pressed against the cured plastic drop by the rod plunger engaging the distal end of the implant rod, which is released from the inner wall of the cannula and unlocks the implant rod.

This prior art has the disadvantage that it is difficult to ensure the reproducible position of the plastic drop in the cannula. In addition, the surface of the implant bar through which the active agent is to be released is variously sealed with a plastic solution, so that parts of the surface are occasionally not available to release the active agent from the implant bar, which can disadvantageously result in irregular delivery of the active agent.

The object of the invention is to provide an improved cannula and an improved cannula device with or for an implant.

The essence of the technical solution

This object is achieved by a cannula with a proximal end arranged for insertion into the tissue in which the implant is to be inserted, a distal end arranged for connection with the cannula holder, an implant channel extending from the distal end to the proximal end, wherein, between the distal end and the proximal end, a lateral opening to the channel and a cannula device with a cannula holder and a cannula according to the invention are provided, wherein the cannula holder and the cannula are connected by force, fit or material contact.

Preferred further embodiments of the invention are defined in the dependent claims.

The cannula comprises a proximal end that is configured to be inserted into the tissue in which the implant needs to be positioned and a distal end that is configured to engage the cannula holder. An implant channel extends from the distal end to the proximal end of the cannula. The essence of the invention lies in the idea of arranging a side opening to the channel between the proximal end and the distal end. Due to this side opening, the elastic member can be applied to the implant in the duct by a force perpendicular to the axis of the cannula. The implant is clamped tightly in the cannula due to the force exerted by the elastic component. Alternatively, the elastic member engages through an opening in a groove or other recess in the implant to hold the implant firmly. According to another alternative, the elastic structural member partially obstructs the channel or reduces its cross-section. In this case, the implant disposed distal to the aperture can only move proximally against the elastic force exerted by the elastic member. In each of said variants, the elastic member is preferably formed such that the implant can be proximally displaced to its distal end by a predetermined force.

For example, the elastic member is an O-ring of rubber, silicone, perbunan, or other elastic material that is placed around the cannula in the region of the opening.

The elastic member may also be formed as a tubing of elastic material displaced in the region of the opening of the cannula therethrough. Elastic materials suitable for the tubing are, for example, rubber, silicone, perbunan and the like. Alternatively, in one preferred embodiment, the tubing may be posos2

It can be melted from a polymeric material which, after being placed through the opening of the cannula, can shrink, for example by means of heat, i.e. heat. Such a heat-shrinkable tubing may, for example, consist of a modified polyolefin, such as heat-shrinkable tubing, available under the trade name Altera MT 2000 from Tyco Electronics Corporation, Swindon, U. K., which are also specified for medical applications, and sterilizable by gamma irradiation.

The elastic tubing, displaced in the region of the opening through the cannula, allows a large contact surface between the tubing and the implant, by means of which the implant can be particularly firmly held in the cannula. At the same time, the large contact area between the tubing and the cannula reliably prevents the elastic element from slipping onto the cannula, so that the firm holding of the implant is ensured even during improper handling, such as removal of the needle cap or similar handling. In addition, the use of a shrinkable tubing also allows complete closing of the side opening of the cannula, which is advantageous for sterility.

When using a tubing of elastic material, preferably a tubing having an inner diameter that is smaller than the outer periphery of the cannula is unstretched. When positioned on the cannula, the tubing preferably slides fully through the side opening of the cannula, which protrudes through the opening into the cannula channel, thus reducing its cross-section in the region of the opening. Preferably, the implant is held firmly in the area of the opening in the cannula. The force exerted by the tubing is sufficient to prevent inadvertent slipping of the implant, but so small that the implant can be easily extended when applied.

When using a tubing of heat-shrinkable material, the tubing preferably has, in its initial state, an inner diameter which corresponds to the outer circumference of the cannula or is slightly larger. For placement, the tubing is pushed through the cannula so that the opening is preferably completely covered and then heated. Shrinking of the tubing causes the tubing to lie tightly around the cannula and penetrate through the orifice into the cannula duct, thereby reducing the cross-section in the region of the orifice. Preferably, prior to shrinking of the tubing, the implant is arranged in the cannula channel in the region of the aperture so that the tubing is also applied to the implant during shrinking and thus fixes the implant in the cannula. If a tubing of sterilizable material is used, it is preferred to perform sterilization after the tubing has been placed and the implant has been fixed if necessary.

Particularly preferably, the elastic member is transparent to allow visual inspection through the opening of the implant firmly retained in the cannula.

The technical solution further comprises a cannula device with a cannula as described above and a cannula holder which is connected to the cannula by force, fit or material contact.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following, preferred embodiments of the present invention are explained in more detail on the basis of the attached figures.

Fig. 1 shows a schematic representation of a longitudinal section through a cannula with a cannula holder;

Fig. 2 shows a schematic representation of a longitudinal section through a cannula with a cannula holder;

Fig. 3 shows a schematic representation of a longitudinal section through a cannula with a cannula holder; and FIG. 4 shows a schematic representation of a longitudinal section of the cannula with the cannula holder.

EXAMPLES

Fig. 1 shows a schematic representation of a longitudinal section through the cannula 10 and the cannula holder 30. The cannula 10 has a proximal end 12, for example with a bevelled tip and optionally a facet cut. The distal end 14 of the cannula W is shaped, rigidly connected or materially connected to the cannula holder 30. The cannula 10 is approximately tubular with a circular or elliptical cross-section. The channel 16 extends from the proximal end 12 to the distal end 14 of the cannula W. The cannula 10 preferably consists of stainless steel or other, pharmaceutically inert material. The cannula holder 30 is, for example, of a pharmaceutically inert plastic. The broken representation of the cannula 10 in FIG. 1 indicates that the cannula can be substantially longer in length than shown in FIG. First

The cannula 10 has a side opening 22 to the channel 16. For example, the side opening 22 is drilled, milled or etched. Through the opening 22, the elastic structural member can exert a holding force on the implant in the channel 16. Examples for the elastic member are described in more detail below with reference to FIG. 2 and FIG. Third

Fig. 2, FIG. 3 and FIG. 4 show schematic representations of longitudinal sections through one cannula 10 and the cannula holder 30 each. FIG. 2, FIG. 3 and FIG. 4, as in FIG. 1, to scale. In particular, for example, the ratios between the length and diameter of the cannula 10 as well as between the diameter and the wall thickness of the cannula 10 can be varied from FIG. 2. FIG. 3 and FIG. 4, differentiate. Also, the tip angle at the proximal end 12, the location, shape, and size of the aperture 22 may differ from those shown in the figures. The serrated edges on the cannula holder 30 indicate that it is shown in FIG. 2, FIG. 3 and FIG. 4 only a part is shown. In channel 16

SK 5914-1 cannula 10 is always an implant 40. Its shape and size may vary from that shown in FIG. 2, FIG. 3 and FIG. 4.

Fig. 2 shows an exemplary embodiment in which the aforesaid elastic member is formed by an O-ring 24 that is placed around the cannula 10. The O-ring 24, in its expanded form, has an inner circumference that is smaller than the outer circumference of the cannula 10. If O is the ring 24 laid around the cannula 10 is expanded. When the O-ring 24 is positioned around the cannula 10 at the aperture 22, it engages at least partially into the aperture 22. This exerts a force perpendicular to the axis of the cannula W when the implant 40 is located in the region of the aperture 22 and the O-ring 24. Due to the adhesive friction between the O-ring 24 and the implant 40, and / or between the implant 40 and the inner wall of the cannula 10, the implant 40 is retained.

A predetermined minimum force is required to move the implant 40 in the cannula channel 16. The dimensions, material and surface quality of the O-ring 24, the shape and dimensions of the aperture 22, the surface properties of the implant 40 and the inner wall of the cannula 10 are preferably selected such that the adhesive frictional forces are multiple times the gravity of the implant 40.

Alternatively, the implant 40 may also have a circumferential groove or other recess in which the O-ring 24 engages. This further increases the force exerted by the O-ring 24 on the implant 40.

Fig. 3 shows an alternative embodiment in which the elastic member is formed by an elastic lever 26 with an engagement end 28. For example, the elastic lever and the engagement end are formed in one piece with the cannula holder 30. The engagement end 28 engages through the side opening 22 into the channel 16. By the implant 40 located in the region of the opening 22 in the channel 16, the elastic lever 26 is deflected from its rest position. The engagement end 28 exerts an elastic force on the implant 40 which acts perpendicularly to the axis of the cannula.

10. As described above with reference to FIG. 2, this causes the implant 40 to be retained in the channel 16 based on the adhesive friction between the engagement end 28 and the implant 40, and / or between the implant 40 and the inner wall of the cannula 10.

Similarly as described above with reference to FIG. 2, alternatively, the implant 40 may also have a circumferential groove or other recess in which the engagement end 28 engages. This further increases the force exerted on the implant 40 by the elastic lever 26 and the engagement end 28.

Fig. 4 shows another exemplary embodiment in which the aforementioned elastic member is formed by a tube 25 which is completely displaced through the cannula 10 in the region of the side opening 22. The tube 25 preferably consists of an elastic polymeric material and in its unstretched form has an inner diameter which is smaller than the outer circumference of the cannula W, so that it at least partially engages in the opening 22. Thus, perpendicularly to the axis of the cannula 10, it exerts a force on the implant 40 when it is in the region of the opening 22 and the tubing 25 laid there. and the implant 40, and / or between the implant 40 and the inner wall of the cannula 10, retain the implant 40. In order to facilitate the placement of the tubing 25 on the cannula 10 in the region of the aperture 22, it is advantageous to use a tubing 25 of heat-shrinkable polymeric material which has an initial diameter that corresponds to the outer periphery of the cannula W or is slightly larger. After such a tubing has preferably been fully positioned over the side opening 22 of the cannula 10, the tubing shrinks due to the corresponding heat supply, thereby tightening the tubing 25 tightly to the outside of the cannula 10 and engaging the channel 16 in the region of the opening 22. by shrinking the tubing 25 arranged in the region of the opening 22 in the cannula channel 16. The use of a transparent tubing 25 preferably allows visual inspection of the position of the implant 40 below the opening 22.

Claims (2)

1. Cannula (10) with: a proximal end (12) arranged to be inserted into the tissue in which the implant is to be inserted, a distal end (14) arranged to connect with the cannula holder, an implant channel (16) extending from the distal end (12). 14) to a proximal end (12), characterized in that a side opening (22) to the channel (16) is arranged between the distal end (14) and the proximal end (12). The cannula (10) of the preceding claim, further comprising an elastic structural member that partially engages the opening (22) to retain the implant (40) in the friction force channel (16). Cannula (10) according to the preceding claim, characterized in that the elastic member comprises an O-ring (24) of elastic material that is arranged in the region of the opening (22) around the cannula (10). Cannula (10) according to claim 2, characterized in that the elastic member comprises a hose (25) of elastic material, which is preferably completely displaced through the cannula (10) in the region of the opening (22). SK 5914-1 Cannula (10) according to claim 4, characterized in that the elastic material of the tubing (25) comprises a polymer, which is preferably arranged on the cannula (10) by heat shrinkage. Cannula (10) according to one of claims 2 to 5, characterized in that the elastic component is transparent. Cannula device with a cannula holder (30) and a cannula (10) according to any one of the preceding claims, characterized in that the cannula holder (30) is connected to the cannula (10) by force, form or material contact. 2 drawings