MXPA99011692A - Preloaded implantation device - Google Patents

Abstract

Disclosed is an implantation device (1) comprising a hollow needle (2), preferably of the type having a chamfered tip profile, and a body (3) adjoining the needle part comprising a plunger (5), preferably having a chamfered tip profile capable of blending with the needle tip profile. The device is made preloadable by being provided with a chamber (7) capable of holding an implant (8), which chamber is positioned radially outside the periphery of the plunger (5) and has a directly or indirectly open connection to a channel (6) surrounding the plunger. The plunger is capable of closing off and opening up the chamber by being displaced.

Description

PRELIMINARY IMPLANT DEVICE The invention relates to a pre-loaded implant device comprising a hollow needle and a body attached to the needle, the body comprising an elongated part extending along the same axis as the needle, a plunger that can be moved within the elongated part and the needle, the periphery of the plunger defining a channel in the elongated part, and a chamber capable of containing an implant. The invention also relates to an implant device that has actually been pre-loaded with an implant. Implant devices are known and serve to introduce subcutaneously a medicinal implant (small bars, pills, tablets, granules and the like, which incorporate a pharmaceutically active substance) in humans or animals, or in subcutaneous tissues of humans or animals in an easy, effective and aseptic way. The implantation of a pharmaceutical preparation subcutaneously or in subcutaneous tissues is normally used in human and veterinary medicine to carry out, for example, prolonged action of the drug. The implant introduced (small bars, pills, tablets, granules, etc.) dissolves slowly around the tissue or slowly releases the drug to the same, and the drug enters the circulation via the blood or lymph in order to be transported later to the site or places where it can carry out its action. Therefore, for example, in gynecology a tablet containing an estrogen, for example estradiol, is implanted in women after double oophorectomy or in women during menopause in order to counteract or prevent certain symptoms that suffer or may suffer women. Said estradiol, or other gynecological implants, are generally inserted subcutaneously in an area where there is relatively little movement, such as the upper outer quadrant of the buttocks or in the lower abdominal wall. In animals, implants containing hormones, for example, are introduced subcutaneously in order to regulate estrus. The invention, as noted above, is in the field of implant devices that can be preloaded. The term "pre-loaded" indicates that the device allows the implant to be present within the device before such a device is used, i.e. comprising a chamber capable of containing a vapor. Said chamber, which can have any suitable shape for any desired implant in order to be coupled thereto, when provided in advance with the implant (ie, in the previously loaded state) makes it easier to control the implant. desired sterility. Particularly, the invention therefore provides easy operation by a specialist or a general practitioner, as well as easy administration per se of the implant: This can be done by simply pushing forward the plunger in such a way that it moves it inside the needle and therefore insert the implant through the needle into the body.

Implantable devices that can be preloaded, of the type mentioned above are known. In this way, e.g., the E.U.A. 5,520,660 discloses a device for administering implants, which comprises a container of active substance with cannula and injection plunger. The plunger is disposed in a channel of the plunger which fuses within the lumen of the cannula. A containment device for the implant is disposed on the side of the lumen-end of the plunger channel. Another prior art of the art which refers to pre-loaded implant devices is EP 402955, which describes a syringe containing a capsule chamber, a hollow needle (removable) mounted on the front end of the capsule chamber, and a plunger, all mounted on a common axis in such a way that the plunger can be passed through the capsule chamber and into the hollow needle to eject a capsule from a solid preparation of the chamber through the needle into the patient's body. Other descriptions of pre-loaded implant devices, placed in line, a hollow needle, a chamber containing the implant and a plunger by means of which the implant can be pushed through the needle, include, E.U.A. 4,661,103, E.U.A. 4,601,699, GB 2-138-298, EP 551 699, and FR 2,231,355. The present invention provides an implant device with which not only the above problems are solved, but also avoids the inconveniences of more outdated methods for subcutaneously introducing tablets containing an active substance. A known implant device serving for this purpose has been described in EP 564 038. A major drawback of previously pre-loaded implant devices is that they do not have the benefits associated with the implant device according to the invention. EP 564 038. Having these benefits, it should be possible for the needle to be beveled at the distal (tip) end, specifically in such a way that it has a sharp tip with which the skin can be pierced, and that it is firmly attached at the end proximal to the body. The plunger (also referred to as a mandrel) also has a distal end (tip) which is bevelled, specifically, precisely at the same angle as the hollow needle. Therefore, the plunger can be pushed into the hollow needle in such a way that the bevelled end coincides precisely with the bevelled end of the hollow needle, as a result of which, a solid needle is produced. With the solid needle formed in this way, the skin and subcutaneous tissue are transferred to the site where the implant is to be inserted, usually at an oblique angle. The advantage of using a bevelled solid needle is that the tissue is separated and not pierced. As a result, the tissue is damaged to a lesser degree and healing of the picket proceeds more quickly, virtually without leaving any scars. With a hollow beveled needle, there is a greater possibility that some tissue in the needle as a result of the action of the perforation, therefore, the damage to the tissue becomes somewhat greater and the healing of the picket some way it takes more time, with a greater probability that there is some visible scar. The implant devices that can be charged previously described above, can not be made to have such a provision. For the plunger it must essentially be in the pushed forward position (in such a way as to allow the tip of the beveled plunger to mix with the tip of the beveled needle) when a patient is stung with the needle. In the devices of the prior art, this can not be done without the out-of-time displacement of the implant of the chamber to the outside of the tip of the needle.

In EP 564 038, a form of operation has been described which involves placing the implant in a chamber during the use of the device, for example, in a precise operation using pliers. Further descriptions of the implant devices that require loading of the implant during operation include E.U.A. 1,789,766, E.U.A. 3,921,632 and DE 806 702. None of these known devices has a chamber capable of containing the implant. This also involves other known injection devices having specifically designed needle tips, for which reference is made, as a background, to E.U.A. 2,751,907 and GB 2,199,247. As will be clear from the foregoing, it is intended with the present invention to provide an implant device which can be preloaded, thereby making it possible to avoid loading the device with the implant during use, but at the same time, it has the possibility of having the provisions that require free movement of the plunger, such as a plunger which is combined with the tip of the needle, in such a way as to avoid undue damage to the patient's tissue. This objective is fulfilled completely by the invention. For this purpose, the invention consists in that in an implant device identified above, of the type that can be preloaded, the chamber is positioned radially outside the channel and has a connection open directly or indirectly with the channel, the plunger, when moving, being able to close and open the camera. Although the benefits of the present invention may be enjoyed in the event that the implant devices have neither a bevelled needle point nor a bevelled plunger tip, it will be clear that it is preferred to have such provisions in accordance with the invention. In this regard, the invention provides a particular improvement in implant devices such as described in EP 564 038, E.U.A. 3,921,632. Essentially this is the type of devices comprising a hollow needle with a bevelled tip profile and a body that attaches to part of the needle, the body comprising (a) an elongated part extending along the same axis as the needle, (b) a piston that can move within the elongated part and the needle, the plunger having a bevelled tip profile capable of combining with the profile of the needle tip, wherein the periphery of the plunger defines a channel in the elongated part; and (c) a chamber capable of containing an implant. The camera of these known devices that can not be pre-loaded, the present invention solves the problem of how to provide a device that can be preloaded without losing the great benefit of the chamfered plunger profile. As described above, the means to solve this problem is that the device is provided with a camera that is positioned radially outside the channel and has an open connection directly or indirectly to the channel, by which, as the plunger is displaced, it is capable of to close and open the camera. The closing and opening of the chamber can be done by simple movement of the plunger. That is, the chamber has an opening of such dimensions on the side of the plunger that, when the plunger retracts backwards from the chamber (i.e., it is pulled to the rear end of the device, whereby it is understood that the end is far away. of the needle), an implant contained within the chamber will automatically enter the plunger channel. It is also possible to make use of forces other than gravity, for example by providing the chamber, on the side that is away from the channel, with an elastic means such as a spring, which pushes the implant against the plunger when closes, and which causes the implant to be pushed from the chamber into the channel when the plunger has been retracted. Apart from the plunger, other means for closing the chamber can be provided. Therefore, other possibilities include a camera closed by an additional latch means, such as a gate which opens automatically when completely withdrawn from the plunger, or any mechanical, electronic or optical means directing the opening of the chamber in such a way that an implant contained therein can move within the channel, at the moment or after the space required in it has become available when removing the plunger. The requirement that, when displaced, the plunger be able to close and open the chamber, not only refers to the way in which the open connection between the chamber and the channel is made, it also refers to the longitudinal poon of the chamber. chamber and the length of the plunger. It will be clear to the person of ordinary skill in the art that the plunger should be long enough to be retracted backwards from the chamber, and that it is preferred that the chamber be at a sufficiently long distance from the rear end of the device in such a way of allowing the plunger to retract enough and still be contained within the body of the device. The device may contain suitable means to ensure that when the plunger is pushed completely into the needle, the point of the beveled needle and the beveled end of the mandrel coincide precisely. The possible means for providing this includes a plunger end (i.e., on the side that is away from the needle) of the conventional type itself, which has a diameter longer than the plunger channel, and therefore it will prevent the plunger from being pushed forward beyond the point at which said plunger end strikes the plunger channel. Other means include a projection on the plunger and the corresponding insertion in the wall of the plunger channel, or vice versa, designed in such a poon that when the plunger has been pushed forward to the desired distance, the projection will be fixed on the insert (comparable to a known principle of an unrelated technique, viz. to that of the well-known ball tips of the BIC® type). As mentioned above, the camera has a radially outward poon of the channel. In general, this means that the camera has a poon which, when the device is being used to administer an implant, can be described as being "on" the channel. By virtue of the direct or indirect open connection of the camera to the channel, an implant contained within the camera will actually enter the channel (as a result of gravity action) when the plunger has been removed (retracted) in such a way that it is released the part of the channel directly below the camera. It is thought that other embodiments should not be excluded, e.g., a camera having a poon which, when using the device, can be described as being "under" the channel and which comprises a spring or the like, which can push forward an implant into the canal. In the case of a needle having more preferably the beveled tip and an associated bevelled plunger, the device is asymmetric with respect to a virtual central axis. Therefore, a "lower" and a "higher" side of the device can be defined. With respect to the same, a preferred embodiment is the following. Considering that the point of the beveled needle, and consequently also the point of the bevelled plunger, are preferably located on the lower side, it is preferred that the chamber capable of containing the implant be placed on the upper side. The parts of the component of the device according to the invention and the feeding of a pre-filled implant are further explained below with reference to the schematic drawings. Each of the figures represents, in longitudinal cross-section, a device according to the invention. The reference signs in each of the figures having the same meaning, all the figures exhibit an implant device (1) having a hollow needle (2) and a body (3) joining the needle (2), the body comprising an elongated part (4) extending along the same axis as the needle (2), a plunger (5) that can be moved within the elongated part (4) and the needle (2), the periphery of the plunger defining a channel (6) in the elongate part (4), and a chamber (7) capable of containing an implant (8). In FIG. 1, a device (1) is shown in which the camera (7) containing the implant (8) is in the closed position. The FIG: 2, shows a device (1) in which the chamber (7) has been opened by retracting the plunger (5) and the implant (8) has been fed into the channel (6). FIG.3 is incorporated to show the additional operation of the device (1), viz. the forward thrust of the implant (8) by means of the plunger (5). The components of the device are generally made of hard material, for example stainless steel. Certain parts of the device can also be made of a suitable plastic, for example, of a type of hard PVC, certain nylon, PTFE, acrylates such as PPMA, polypropene, polystyrene, polycarbonate or polyoxymethylene. Preferred synthetic materials are those that can be sterilized, more particularly those that can withstand sterilization? Such materials are known to those of ordinary skill in the art. Preferred synthetic materials are ABS (acrylonitrile, butadiene, and styrene terpolymer) and SAN (styrene-acrylonitrile copolymer). Without excluding the possibilities of using other conventional materials for the part of the needle and said elongated part, or at least the distal portions thereof, they are generally formed of metal, preferably stainless steel. The implant devices of the invention can be manufactured using conventional techniques known to those skilled in the art. The body, which may serve as a holding part or which may comprise an additional holding part, is thinner than the part of the needle and may be tubular, but may also have a different cross-section. The fastening part, of course, must have a shape such that the device can be easily attached for the purpose for which the device is intended. Therefore, depressions can be provided in which the fingers, for example the thumb and index finger, are adapted, in order to allow the device to be firmly held during use. The implants are contained within the chamber, and, consequently, the chamber itself can have any shape. A frequently occurring shape is a bar in cylindrical or rectangular cross section, such as in the case of an implant tablet which contains estradiol and which is made under the trade name Dimenformon by N.V. Organon Oss, The Netherlands. Other examples of implants that can be used to make pre-loaded implant devices according to the invention are estradiol implants such as Riselle®, Meno-Implant®, contraceptive implants such as Implanon®, or other hormonal implants such as testosterone implants. The device of the present invention, which is also suitable for introducing hormonal implants, can also be used for implants containing other active substances than hormones, and can be used for the implant in other types of tissue in addition to the lipid tissue.

Claims (3)

1. CLAIMS 1. An implant device (1) comprising a hollow needle (2) and a body (3) attached to the needle, the body (3) comprising an elongated part (4) extending along the same axis as the needle ( 2), a plunger (5) that can move inside the elongated part (4) and the needle (2), the periphery of the plunger (5) defining a channel (6) in the elongated part (4), and a chamber (7) capable of containing the implant (8), characterized in that the chamber (7) is positioned radially outside the channel (6) and has direct or indirect open connection to the channel (6), the plunger (5) that is capable to close and open the camera (7) when being moved. An implant device (1) comprising a hollow needle (2) having a bevelled tip profile and a body (3) that is attached to the needle (2), the body (3) comprising an elongated part (4) ) that extends along the same axis of the needle (2), a plunger (5) that can move inside the elongated part (4) and the needle (2), the plunger (5) having a tip profile bevel of the combination with the profile of the tip of the needle, wherein the periphery of the plunger (5) defines a channel (6) in the elongate part (4), and a chamber (7) capable of containing an implant (8). ), characterized in that the chamber (7) is positioned radially outside the channel (6) and having a direct or indirect open connection to the channel (6), the plunger (5) being able to close and open the chamber (7) to be displaced. 3. An implant device according to claim 1 or 2, characterized in that it is loaded with an implant (8) contained in the chamber (7).