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 releasably attached to the slider,

- a needle having a first end and a second end, arranged to move within the slider,

- a plunger arranged inside the slider, partially inside the needle and attached to the cover, and

- a first elastic element arranged inside the cover to move the slider when the sliding means is released from the slider, wherein the slider is arranged to move in relation to the plunger. 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

Fig. 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. 3 shows an inserter according to another embodiment, as an exploded view. Fig. 4A-4B show the inserter of Figure 3, as a cross-sectional view.

Fig. 5 illustrates a locking means according to an embodiment of the invention.

Fig. 6 illustrates an inserter according to another embodiment.

Fig. 7 illustrates the inner mechanism of an inserter according to yet another embodiment.

Fig. 8 illustrates the cross-section of the inner mechanism of Figure 7 as seen inside the cover.

DETAILED DESCRIPTION OF THE INVENTION

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 releasably attached to the slider,

- a needle having a first end and a second end, arranged to move within the slider, - a plunger arranged inside the slider, partially inside the needle and attached to the cover, and

- a first elastic element arranged inside the cover to move the slider when the sliding means is released from the slider, wherein the slider is arranged to move in relation to the plunger.

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. 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 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 cover slot has a shape such as it fixes the sliding means when the sliding means is attached to the slider. 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 sliding means is attached to the slider in a releasable manner, i.e. detaching the sliding means from the slider requires an active action from the user. According to an embodiment, the slider comprises at least one slider slot along its longitudinal direction, for allowing movement of the slider in relation to the plunger. The slider may also comprise two slider slots along its longitudinal direction, preferably the two slider slots are diametrically opposed to each other and have essentially the same size and shape. The slider may also be moved by the elastic element, as is explained in more detail below.

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.

In the present inserter, the plunger is attached to 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. Further, the slider is arranged to move with respect to the plunger. According to an embodiment, the plunger is attached to the cover by a pin. When such a pin is used, it can be arranged to pass through the at least one slider slot. In case of two diametrically opposed slider slots, the pin may pass through both slider slots. Most preferably, the attachment is done via the part of the plunger that is not inside the needle.

The inserter further comprises a first elastic element arranged inside the cover. The position of the first elastic element is such that it moves the slider when the sliding means is released from the slider. According to an embodiment, the first elastic element is a spring arranged between the first end of the cover and the first end of the slider. When the sliding means is released, the spring can move the slider backwards (i.e. towards the second end of the cover), at the same time retracting the needle and releasing the implant from inside the needle.

According to another embodiment, the first elastic element is arranged between the second end of the slider and the second end of the cover and attached to the second end of the slider and the second end of the cover. At his position, the first elastic element can withdraw the slider towards the second end of the cover, when the slider is released from the sliding means. The first elastic element can be for example a silicone band or a spring.

The inserter may also comprise locking means for releasably locking the sliding means to the cover. Using such locking means would enhance security of the inserter, as it would securely prevent needle retraction before the sliding means is actioned and released from the slider.

The slider may also comprise a second elastic element exerting a force on the sliding means, the force being directed outward from the slider. The second elastic element thus pushes the sliding means outwards from the slider. When this is combined with the locking means mentioned above, security is yet still enhanced and releasing the slider from the sliding means requires a more significant force from the user. The second elastic element may be for example a spring or a block made of an elastic material, such as silicone.

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. The inserter may also or instead comprise mechanical means limiting the movement of the slider 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 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 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. 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. According to yet another embodiment, the inserter comprises an inner mechanism comprising a longitudinal locking means, a plunger means, a handling means and a slider, which are slightly different from what has been described above. Indeed, the locking means is longitudinal and extends on almost the entire length of the inserter. It comprises means, such as a toothed surface working as a cockwheel, that function with the slider to control its movement, equipped with fitting means, for example a toothed surface corresponding to the toothed surface of the locking means. The locking means also has means for controlling the movement of the plunger means, for example a pair of protrusions when the plunger means is equipped with a similar protrusion, arranged to fit within a slot created by the two protrusions of the locking means. The plunger means and the slider have surfaces arranged to abut against one another, during the insertion process, to indicate that the implant has been expulsed from the needle. The dimensions of the various parts are designed to ensure this. Likewise, the handling means (attached to the slider) and the locking means have surfaces adapted to abut against one another, in order to indicate that the needle has been fully retracted within the inserter. In this embodiment, the form of the plunger means is such that it can slightly deform under pressure, thus making the means for controlling its movement to give away and enable its 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 can be 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. It is furthermore possible that the insertion is done while the needle is outside the inserter, at the option of the person performing the insertion. 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. The retraction of the needle is caused by releasing the sliding means from the slider. 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.

Figure 3 shows an inserter according to another embodiment, as an exploded view and Figures 4A and 4B show the inserter of Figure 3, as a cross-sectional view. In this embodiment, the inserter comprises a cover 31 having a first end 31a and a second end 31b. The cover 31 is equipped with a cover slot 35. Sliding means 36 is arranged in the cover slot 35, in a moveable manner and as can be seen in Figures 4A and 4B, it is releasably attached to a slider 37. The slider 37 is movably arranged inside the cover 31, and it has a first end 37a and a second end 37b. It is also arranged to move in relation to a plunger 34. The plunger 34 is arranged inside the slider 37, partially inside a needle 32 and attached to the cover 31. The needle 32 is arranged to move within the slider 37 and it also has a first end 31a and a second end (not shown).

The slider 37 comprises a slider slot 38, through which the plunger 34 is attached to the cover 31, by the use of a pin 39. The inserter further comprises a first elastic element, which in this embodiment is a spring 40. The spring 40 is arranged inside the cover 31, in this embodiment between the first end 31a of the cover and the first end 37a of the slider, in order to move the slider 37 when the sliding means 36 is released from the slider 37. The inserter also comprises a second elastic element, which in this embodiment is an elastic block 41. The elastic block 41 is arranged on the slider 37, between the slider 37 and the sliding means 36, in order to exert a force on the sliding means, the force being directed outward from the slider 37. In Figure 4A, the sliding means 36 is blocking the movement of the slider 37 and in Figure 4B, it has been released and the slider 37 has moved backwards, by the force of the spring 40. At the same time, the needle 32 has partially retracted within the cover 31.

Figure 5 illustrates a locking means 54 according to an embodiment of the invention. The locking means 54 is arranged at the side of the cover slot on which the sliding means 36 is arranged. When the elastic block 41 is pushing the sliding means 36 outwards from the cover, the locking means 54 ensures that the slider remains in place. The user will need to actively push down the sliding means 36, in order to release the slider.

Figure 6 illustrates an inserter according to another embodiment. In this embodiment, the first elastic element is a spring 60 arranged in the proximal part of the cover 61. It is attached to the slider 67 by one of its ends and to the end of the cover 61 at its other end. The spring thus pulls the slider 67 backwards, when the sliding means 66 is released in the cover slot 65, thereby retracting the needle 62 inside the cover. Figure 7 illustrates the inner mechanism of an inserter according to yet another embodiment. The inner mechanism comprises a longitudinal locking means 71, a plunger means 72, a handling means 73 and a slider 74.

The longitudinal locking means 71 has a first end 71a and a second end 71b. The locking means 71 comprises, towards its first end 71a, a portion equipped with a toothed surface 75, working as a cockwheel together with the slider 74 as explained below. Furthermore, the locking means 71 comprises two protrusions 712 arranged to work together with the plunger means 71, as explained below. The locking means 71 also has a surface 713 arranged to work together with the handling means 73 as explained below. The second end 71b of the longitudinal locking means is arranged to form the second end of the handle of the inserter, while the rest of the locking means 71 is arranged inside the cover.

The inner mechanism further comprises plunger means 72 which functions as plunger for expulsing the eye implant from the inserter. The plunger means 72 has a first end having a surface 721 and a protruding shape 722 arranged to fit between the two protrusions 712 of the locking means 71. The form of the plunger means 72 is such that it can slightly deform under pressure, thus making the protrusion 722 to slip out of the indentation formed by the protrusions 712, and therefore enable its movement.

The handling means 73 is in the form of a knob comprising a surface 733, arranged to abut against the surface 13 of the locking means 71. The knob further comprises a toothed surface fitting the toothed surface 75 of the locking means. The slider 74 is attached to the handling means 73 and has a surface 741 arranged to abut against the surface 721 of the plunger means 72. In this embodiment, when the inserter is in its initial position (i.e. unused), the distance between the surfaces 741 and 721 is smaller than the distance between the surfaces 733 and 713.

When the inserter is used, and the needle is in its place inside the eye, the handling means 73 is pushed in a direction perpendicular to the longitudinal axis of the inserter, i.e. downwards, and then towards the second end of the slider (towards the user). The slider 74 is thus allowed to move towards the second end of the handle and the needle retracts while the plunger means 72 remains immobile, resulting in the implant being expulsed out from the needle. When the movement is continued, the surfaces 741 and 72-2- 721 come into contact and the plunger means 72 is in consequence moved also towards the second end of the handle. When the surfaces 733 and 713 come into contact, the needle and the plunger are is fully retracted inside the handle, and insertion is complete.

The surface 713 can also be replaced by an indentation within the locking means 71, of such size and shape that the knob of the handling means 73 can be arranged therein. Figure 8 illustrates the cross-section of the inner mechanism of Figure 7 as seen inside the cover. The cover 76 is of such shape that the plunger means 72 and the locking means 71 fit snugly therein. It is even possible that the locking means partly replaces the cover.