WO2018091362A1

WO2018091362A1 - An inserter for an eye implant

Info

Publication number: WO2018091362A1
Application number: PCT/EP2017/078864
Authority: WO
Inventors: Joonas Mikkonen; Taina TJÄDER; Mikael Stolt; Manja Ahola
Original assignee: Bayer Oy
Priority date: 2016-11-18
Filing date: 2017-11-10
Publication date: 2018-05-24

Abstract

The present invention relates to an inserter for an eye implant, comprising a hollow cover (31) having a first end and a second end and at least one cover slot (35) along its longitudinal direction; a slider (37) movably arranged inside the cover, having a first end and a second end; sliding means (36) movably arranged in the cover slot and attached to the slider, for moving the slider; a needle (32) having a first end and a second end, attached to the slider; and a plunger (34) arranged inside the cover and partially inside the slider at the second end of the slider, and partially inside the needle; wherein the plunger is arranged to move together with the slider when the slider is moved in a first direction, and the plunger is arranged to remain stationary when the slider is moved in a second direction opposite the first direction.

Description

AN INSERTER FOR AN EYE IMPLANT

FIELD OF THE INVENTION

The invention relates to an inserter for an eye implant. The inserter comprises a cover, a plunger arranged inside the cover and a needle. The eye implant is arranged inside the needle.

BACKGROUND OF THE INVENTION

Inserters for eye implants are known in the art. The known inserters are based on a structure where a plunger is arranged inside a needle, the needle is attached to a handle, and the implant is pushed out of the fixed needle by the moving plunger. Such structures apply a considerable amount of force on the implant, which due to its size and constitution, is rather fragile. Another problem that may be encountered with this kind of inserter is that when the implant is inserted, the implant is pushed into the eye tissue on its own.

Another known inserter has a needle and a plunger therein, wherein the needle is retracted to release the implant from the needle. In this inserter however, the plunger passes through the whole inserter (i.e. including the handle), and for a small needle, the small plunger can easily bend and thus jam.

A further problem with the known inserters for eye implants is their ergonomic. Indeed, an inserter that is used in a manner similar to a syringe may not be ergonomically optimal for eye insertion. OBJECTS AND SUMMARY OF THE INVENTION

There exists thus a need to provide an inserter for eye implants that is safe and ergonomic to use, easy to manufacture and that does not damage the eye implant during its insertion. The present description relates to an inserter for an eye implant, comprising

- a hollow cover having a first end and a second end and at least one cover slot along its longitudinal direction,

- a slider movably arranged inside the cover, having a first end and a second end,

- sliding means movably arranged in the cover slot and attached to the slider, for moving the slider,

- a needle having a first end and a second end, attached to the slider, and

- a plunger arranged inside the cover and partially inside the slider at the second end of the slider, and partially inside the needle, wherein the plunger is arranged to move together with the slider when the slider is moved in a first direction, and the plunger is arranged to remain stationary when the slider is moved in a second direction opposite the first direction. The present description also relates to a kit comprising an inserter as described above and at least one eye implant.

BRIEF DESCRIPTION OF THE DRAWINGS

Figures 1A-1D schematically illustrate an inserter according to an embodiment and the basic principle of insertion. Fig. 2A-2C schematically illustrate different cross-sections of implants within a needle.

Fig. 3A-3C illustrate an inserter according to an embodiment.

Fig. 4A-4E illustrate yet another inserter according to the present description.

DETAILED DESCRIPTION OF THE INVENTION

The present description relates to an inserter for an eye implant, comprising

- a needle having a first end and a second end, attached to the slider, and

- a plunger arranged inside the cover and partially inside the slider at the second end of the slider, and partially inside the needle, wherein the plunger is arranged to move together with the slider when the slider is moved in a first direction, and the plunger is arranged to remain stationary when the slider is moved in a second direction opposite the first direction.

It is believed that the present inserter overcomes the problems in prior art inserters. Indeed, as the plunger is attached to the cover (either directly or via a supporting part), only a minimal length of the plunger is left unsupported, and thus there is a lesser risk for the plunger to bend or to get jammed inside the needle. A further advantage is that as the implant is inserted into the correct position together with the needle, and thereafter the needle is retracted leaving the implant in place, the implant does not need to be pushed into the eye tissue on its own. This increases the probability that the implant is correctly positioned and does for example not bend during insertion.

In the present description, by first ends are meant the proximal ends, i.e. the ends that are closer to the eye when the inserter is used for inserting an eye implant. The second ends are the opposite ends to the first ends, i.e. the distal ends that are closer to the user of the inserter when an eye implant is being inserted.

The cover of the inserter functions also as a handle of the inserter. It preferably has a form suitable for handling, such as a cylinder or with a proximal part that is cylindrical and a distal part having a larger, rounded shape, making it suitable for handling. The cover may also have an adjustable length, to best suit the size of the hand of the person handling the inserter. The cover thus preferably has a longitudinal shape, i.e. its length (the distance between its first end and its second end) is significantly larger than its other dimensions. The cover also has at least one cover slot along its longitudinal direction. The length of the cover slot is defined by the dimensions of the other parts as will be discussed below. The width of the cover slot is rather small, for example up to 40 %, preferably up to 30 %, more preferably up to 20 % of the circumference of the handle, or in case the cover has a rectangular cross-section, of the width of the side of the rectangle it is located on. In one example, the cross-section of the handle is 12 mm, and the width of the cover slot is 5 mm. The cover slot extends through the thickness of the hollow cover's wall, i.e. from the outside of the cover to its inside. The slider is arranged inside the cover, in a manner that it can move therein. It also has a longitudinal shape as the cover. It is moved with the help of the sliding means, which is arranged on the cover slot in a movable manner. The sliding means can be for example in the form of a button or a rounded piece arranged around the cover of the inserter.

The plunger is arranged inside the cover and partially inside the slider. The plunger is also arranged partially inside the needle. The plunger is arranged to move together with the slider when the slider is moved in a first direction, and the plunger is arranged to remain stationary when the slider is moved in a second direction opposite the first direction. According to a preferred embodiment, the first direction is the direction from the second end of the cover towards the first end of the cover, along a longitudinal axis of the cover.

The plunger is thus partially movably connected to the slider. For example, the second end of the slider may comprise a shape such that a first end of the plunger fits inside the slider. The second end of the slider may for example have a hollow cylindrical part and an opening at its second end surface, wherein the opening has a smaller diameter than the hollow parts inside diameter. The first end of the plunger may then have a protruding shape that is larger than the major part of the plunger. The narrower part may be arranged to pass through the opening at the second end of the slider, and the larger part may fit loosely in the hollow part of the slider, but not be able to pass through the opening.

The needle is dimensioned such that the eye implant is arrangeable inside the needle for insertion. The needle is typically manufactured from a metallic material, such as stainless steel. According to an embodiment, the plunger is arranged to remain stationary, when the slider is moved in the second direction for a pre-determined distance and to move together with the slider, when the slider is moved in the second direction further than the pre-determined distance. In this embodiment, the plunger remains stationary while the implant is being expulsed from the needle, and thereafter start moving backwards. The total distance the slider is moved in the second direction can be arranged to be sufficient to retract the needle within the cover.

Indeed, the plunger may be shaped in such way that it does not move until the slider reaches the proximal part of the plunger and starts pushing also the plunger backwards. This allows the implant inside the needle to drop at the certain depth adjusted by the plunger length. The needle and the plunger then retract inside the inserter after the implant is in position. When designing the inserter the thickness of the proximal part of the plunger can be used to adjust whether the plunger is left out of the inserter or retracted fully in with the needle.

According to another embodiment, the inserter also comprises an elastic element arranged inside the cover, between the first end of the cover and the first end of the slider. This elastic element restricts the forward movement of the slider and ensures also during transportation that the needle stays inside the cover. The elastic element may be for example a spring or a strip of an elastic material such as silicone rubber.

The spring(s) used in the present invention are preferably made of metallic wire in a coil form. Majority of the other parts, with exception to the needle, are made in plastic materials such as polyolefins or polyamides. They may also be made of fiber reinforced plastic materials or metal, such as stainless steel, titanium or titanium alloys. According to yet another embodiment, the inserter also comprises frictional means limiting the movement of the slider with respect to the cover and/or the movement of the plunger with respect to the cover. The inserter may also or instead comprise mechanical means limiting the movement of the slider and/or plunger with respect to the cover. These mechanical means can be for example a slope element or a combination of a threaded rod and a bolt. These means are thus means for adjusting the movement of the needle. Indeed, before insertion, it may be beneficial to fix the needle in such a manner that it does not retract while the needle is injected into the eye. The means adjusting the movement of the needle can be achieved for example by friction between the components or a mechanical shape between the cover and/or plunger and the sliding parts (slider and/or sliding means). It is also possible to place a spring between the second end of the inserter cover and the slider and/or plunger to prevent a retracting movement of the needle happening too easily. Another option could be to use a slope element that restricts the movement of the slider and/or plunger. A yet further possibility is to retract the movement with a threaded rod and a bolt that the moving slider needs to wind along the threaded rod, increasing the friction of the slider movement.

The inserter should be designed to be such that the eye implant is always inserted to a correct depth. This insertion depth can for example be adjusted by the length of the plunger. It could also be adjusted by the size of the other components of the inserter. A person skilled in the art would be readily able to design the size of the inserter to achieve the correct insertion depth.

The inserter according to the present description functions as follows. In the beginning of the insertion process, the needle is at least partially, preferably entirely, retracted inside the inserter (by the manufacturer), and the tip of the inserter is pressed against the surface of the eye. It is also possible that the needle is outside the inserter when the inserter package is opened, and the person performing the insertion retracts it inside the inserter. Thereafter, the user moves the plunger forward, towards the eye, moving the needle and the implant along. In a next step, the needle retracts while the implant and the plunger remain at their positions, thus allowing the needle to release the implant into the eye at a certain depth. In a final, optional step, the plunger also retracts.

It might also be necessary to press the injection site a few minutes after the insertion has been done, in order to ensure that the small incision is correctly closed. This could be done by using the tip of the inserter, i.e. by maintaining the inserter in place a few minutes after the needle has been retracted. The tip of the inserter may be designed to optimise this step, too.

A possibility for insertion of two implants could also be required if a higher drug dose is required. One solution for this would be two parallel needles that both insert a single implant using the embodiments described earlier. It would also be possible to position two implants inside one needle, one after another. When releasing the distal implant, the needle would preferably have a flange or a mark to show the correct insertion depth for the first implant. There could be a mechanical stopper of the movement of the slider that tells the user that the first implant is released. For the second implant, the needle would then be inserter fully into the eye and the needle could then be retracted fully, releasing the second implant.

According to an embodiment, the inserter thus further comprises means for indicating that a first implant has been released from the inserter. The inserter may also further comprise means for stopping the movement of the sliding means when a first implant has been released from the inserter. In a yet another embodiment, the inserter comprises a second needle arranged to move within the slider and in contact with the plunger.

After the eye implant has been inserted and the needle has retracted, it would be preferable, for hygienic reasons, to prevent re-use of the inserter. To this end, the movement of the needle after retraction could be blocked with a mechanical shape or similar, as described above. For example a mechanical shape or a slope could lock the slider inside the inserter.

In some embodiments, it might also be necessary or preferable to attach the eye implant inside the needle, in order to prevent it from falling out before insertion. This could be achieved for example in a mechanical manner, by using eye implants with cross-sections that fit snugly inside an essentially cylindrical needle. For example, the cross-section of the eye implant could oval, triangular or square. Thereby friction would hold the implant inside the needle, while the implant would still be easily released using the plunger, due to a small contact area between the implant and the needle, i.e. only a small force is needed to overcome the friction.

Another option could be to arrange a small protrusion at the tip of the needle, to prevent the eye implant from falling out of its own. A yet further option could be to use a small amount of glue to attach the implant or part of the implant to the inner surface of the needle. Similarly, a small amount of a solvent capable of dissolving the surface of the implant in order to attach it to the inner surface of the needle could be used. Furthermore, it may be suitable to use a small cap at the tip of the inserter or at the tip of the needle, to ensure that the implant is maintained in correct position during transportation of the inserter in its package. The cap may comprise for example a small metallic spike inserted inside the tip of the needle.

The present description relates also to a kit comprising an eye inserter as has been described above, and at least one eye implant arranged inside the needle of the inserter. The eye implant can be any suitable eye implant, such as made of an elastomeric material comprising a therapeutically active agent. The eye implant could also be made of a degradable material that releases the therapeutically active agent when it degrades. Furthermore, the eye implant can be made of a material which degrades so slowly that it can first release the therapeutically active agent (for example by diffusion) and only after essentially all of the therapeutically agent is released, the implant material degrades.

DETAILED DESCRIPTION OF THE DRAWINGS

Figures 1A to ID schematically illustrate an inserter according to an embodiment and the basic principle of insertion using an inserter according to an embodiment of the present disclosure. Figure 1A shows an outer surface of the eye 10, against which the tip of the inserter cover 11 has been pressed. The needle 12 is inside the cover and the implant 13 is inside the needle 12. The implant 13 is arranged at the tip of the plunger 14. In Figure IB, the needle 12 has already been inserted inside the eye, but the implant 13 is still inside the needle. In Figure 1C the implant is being released. Indeed, as can be seen, the needle 12 has been retracted and the implant 13 is outside of the needle, but still in contact with the plunger. In Figure ID, the implant 13 is released and both the plunger 14 and the needle 12 are retracted within the cover 11.

Figures 2A to 2C schematically illustrate different cross-sections of implants 23a, 23b and 23c within a needle 22. These cross-sections, which are triangular for the implant 23a, rectangular for the implant 23b and oval for the implant 23c create a certain amount of friction between the implant and the inner wall of the needle, thus keeping the implant in place within the needle.

Figures 3A to 3C illustrate an inserter according to an embodiment. In this embodiment, the inserter comprises a cover 31 with a cover slot 35, in which a sliding means 36 is movably arranged. The sliding means 36 is attached to a slider 37. The slider 37 has a first end 37a and a second end 37b. A needle 32 is arranged to move within the slider 37 and spring 30 is arranged between the first end (the tip) of the cover and the first end of the slider 37a.

The inserter also comprises a plunger 34 arranged inside the cover and partially inside the slider 37 at the second end of the slider 37, and partially inside the needle 32. The plunger 34 has a first end 34a and a second end 34b. The first end 34a has a shape that first inside the slider 37, which has a hollow, cylindrical part towards its second end 37b. The second end 37b also has an opening through which the plunger 34 can pass. However, the only part of the plunger 34 that can pass through this opening is a middle portion of the plunger that has a smaller cross-section than the end parts. Indeed, the second end 34b of the plunger 34 is again larger than the opening at the second end 37b of the plunger.

Figure 3A illustrates the situation at the beginning of insertion, where the needle 32 is retracted inside the cover 31. In Figure 3B, the inserter tip has been pressed against the surface of the eye and the user has pushed the sliding means 36 towards the proximal end of the inserter. The movement of the sliding means 36 moves the slider 37 and also the plunger 34. The spring 30 is in a compressed state. In Figure 3C, the spring 30 has been released and it has moved the sliding means 36 and the slider 37 backwards. At the same time, the needle 32 has retracted inside the cover and the plunger 34 has remained in place. Thus the implant 33 is expulsed from the needle.

Figures 4A to 4E illustrate yet another inserter according to the present description. In this embodiment, the inserter is designed for insertion of two implants and comprises the same parts as discussed above, i.a. a needle 42, a slider 47, a plunger 44 and sliding means 47. There are two implants 43a, 43b arranged inside the needle, one after the other, in the configuration shown in Figure 4A, which is the situation before insertion. The plunger 44 has a part that extends inside the needle, up to the second end of the second implant 43b.

Figure 4B illustrates the situation where the first implant 43a has been released from the needle and the movement of the slider 47 and the sliding means 46 has been stopped to indicate that the first implant is released. The means for stopping the movement of the sliding means 46 is in this embodiment a first part 50 shaped such as to stop the movement mechanically. As the first part 50 stops the movement of the slider 47 and the sliding means 46, the user will notice that the first implant has been released. Furthermore, a second part 51 has been arranged at the second end of the slider, to prevent backwards movement of the plunger 44. The second part 51 can be for example an indentation on the side of the slider slot, thus stopping movement of the plunger 44 mechanically.

Figure 4C illustrates a further step in the insertion process. The sliding means 46 and the slider 47 have been pushed forward and the needle 42 (with the second implant 43b inside it at its tip) and the plunger 44 have moved to the same depth as in the beginning of the insertion process. In Figure 4D, the second implant 43b has been released from the needle 42, after slightly changing the insertion position. The sliding means 46 has been released again to retract the needle 42, for the second implant 43b to be released. During this step, the plunger does not move due to friction or a mechanical shape.

Figure 4E shows the final situation, where the needle 42 is fully retracted within the cover of the inserter. The sliding means 46 has been moved backwards with a force that is sufficiently high to overcome the force that stopped the plunger in the previous step.

The inserter thus comprises means for stopping the movement of the slider and/or the plunger at various insertion steps. These means are such that the movement is stopped but movement is allowed when a higher force is exerted on the sliding means.

Claims

1. An inserter for an eye implant, comprising

- a needle having a first end and a second end, attached to the slider, and

2. An inserter according to claim 1, further comprising a spring arranged inside the cover, between the first end of the cover and the first end of the slider.

3. An inserter according to claim 1 or 2, wherein the first direction is the direction from the second end of the cover towards the first end of the cover, along a longitudinal axis of the cover.

4. An inserter according to any of the preceding claims, wherein the plunger is arranged to remain stationary, when the slider is moved in the second direction for a pre-determined distance and to move together with the slider, when the slider is moved in the second direction further than the pre-determined distance.

5. An inserter according to claim 4, wherein the total distance the slider is moved in the second direction is sufficient to retract the needle within the cover.

6. An inserter according to any of the preceding claims, further comprising frictional means limiting the movement of the slider and/or the plunger with respect to the cover.

7. An inserter according to any of the preceding claims, further comprising mechanical means limiting the movement of the slider and/or the plunger with respect to the cover.

8. An inserter according to claim 7, wherein the mechanical means is a slope element or a threaded rod and a bolt.

9. An inserter according to any of the preceding claims, further comprising means for indicating that a first implant has been released from the inserter.

10. An inserter according to any of the preceding claims, further comprising means for stopping the movement of the sliding means when a first implant has been released from the inserter.

11. An inserter according to any of the preceding claims, further comprising a second needle arranged to move within the slider and in contact with the plunger.

12. A kit comprising an eye inserter according to any of the claims 1-11 and at least one eye implant arranged inside the needle of the inserter.