DE102011100371A1 - Instrument for subretinal insertion of an implant - Google Patents

Abstract

The invention relates to an instrument for subretinal insertion of an implant 12 into a human or animal eye. The instrument comprises a holding part (14) for holding the instrument (10) by a surgeon, a nozzle (16) with a cavity for receiving the implant (12) and with a dispensing opening (18) for dispensing the implant (12) Piston (20) for pushing out the implant (12) from the discharge opening (18) of the nozzle (16) and an actuating device (22) for actuating the piston (20) by an operator.
According to the invention, the nozzle (16) is arranged stationarily in relation to the holding part (14). The piston (20) is displaceable by the actuating device 22 relative to the holding part (14) within the nozzle (16), so that thereby pushing out of the implant (12) from the discharge opening (18) of the nozzle (16).

Description

The invention relates to an instrument for subretinal insertion of an implant into a human or animal eye.

For example, subretinal implant placement may be used to treat age-related macular degeneration (AMD).

The majority of AMD patients do not yet have effective treatment options. While in the early stages neovascular forms of AMD can now be effectively palliatively treated by means of repetitive injections of VEGF inhibitors, no therapy is available for atrophic ('dry') forms of manifestation. Complications of the wet late form of AMD such. As a subretinal bleeding require surgical therapy, with the pigment epithelium is completely destroyed in most cases today.

Replacement of function-impaired submacular RPE cells (retinal pigment epithelium) is a useful therapeutic target for advanced forms of AMD to restore the homeostasis of the RPE / photoreceptor complex, ie to provide the photoreceptors with a functional RPE. An overview of this can be found in the following publication: Binder S, Stanzel BV, Cancer I, Glittenberg C. Transplantation of the RPE in AMD. Prog Retin Eye Res 2007; 26: 516-554 , The transplantation of homologous RPE cells showed no improvement in vision in patients with AMD in clinical trials, which was explained among other things by a delayed immune reaction. In order to avoid immune reactions, two treatment concepts with autologous RPE have been clinically established in recent years. On the one hand, this is the transplantation of a cell suspension or a translocation of an explant consisting of RPE and choroid.

The onset of solid therapeutic constructs between photoreceptors and RPE (= subretinal implantation) may serve to regenerate the RPE, the photoreceptors, or both.

Bhatt et al. used a straight glass pipette to inject the cultured collagen RPE membranes and additionally stabilized the implant with a sucrose solution ( Bhatt NS, Newsome DA, Fenech T, et al. Experimental transplantation of human retinal pigment epithelial cells on collagen substrates. On J Ophthalmol 1994; 117: 214-221 ).

Another instrument for inserting a subretinal implant is in DE 29819018 U1 described.

Furthermore, instruments for this purpose are off EP 0 967 919 B1 and WO 00/76403 A1 known.

A disadvantage of the instruments known from the prior art is that they do not allow a precise positioning of the implant under the retina, without running the risk of injuring the surrounding structures during the procedure. This is due to the fact that the known instruments must be inserted through an opening in the retina, which is why the surgeon must act with extreme caution during the procedure. Furthermore, the insertion of the instruments into the retina does not allow an unhindered view of the implant to be inserted so that it can no longer be exactly positioned when it is actually inserted under the retina.

The object of the invention is to provide an instrument for subretinal insertion of an implant, which reduces the risk of possible traumatization of the surrounding tissue during surgery and allows a more precise insertion of the implant.

The object is achieved according to the invention by the features of claim 1.

The instrument according to the invention has a holding part for holding the instrument by an operator. This may be, for example, a section of the instrument where it can be grasped by the hand of the surgeon. With this holding part a nozzle is connected. This is preferably arranged distally of the holding part. The term "distal" in the present application means "toward the surgical site" while "proximal" means "towards the hand of the surgeon grasping the instrument". The nozzle has a cavity for receiving the implant. This cavity does not have to be completely closed by the nozzle and may, for example, also have partially open sections. The nozzle further has a dispensing opening for dispensing the implant. This dispensing opening is preferably located at the distal end of the nozzle.

Furthermore, the instrument has a piston for pushing out the implant from the discharge opening of the nozzle. This piston may have any shape suitable for pushing out the implant. Preferably, the shape of the piston is adapted to the shape of the inside of the nozzle, wherein the outer dimensions of the piston may be smaller by several micrometers than the inner dimensions of the nozzle. For example, the piston may look like a spike or punch Plastic, in particular be formed of Teflon. Preferably, the piston is displaceable within the cavity of the nozzle.

The instrument further includes an actuator for actuating the piston by an operator. This may be a mechanical actuator that allows manual actuation of the piston. The actuator thus causes displacement of the piston relative to the nozzle. Such actuators are known in the art

According to the invention, the nozzle is arranged stationarily in relation to the holding part. This means that the nozzle is not displaceable relative to the holding part. During actuation of the instrument thus no displacement of the nozzle relative to the holding part takes place. For this purpose, the nozzle may for example be formed integrally with the holding part. Further, the nozzle via appropriate fastening devices, such as screws or the like may be firmly connected to the holding part.

According to the invention, the piston is displaceable by the actuating device relative to the holding part within the nozzle. Instead of a displacement of the nozzle relative to the holding part thus takes place on actuation of the actuator displacement of the piston relative to the holding part, whereby a pushing out of the implant from the discharge opening of the nozzle takes place.

According to the invention, the implant is thus pushed out of the nozzle by the piston, while the nozzle does not move when the actuating device is actuated relative to the holding part and thus also towards the eye and the retina. In other words, during the actual insertion of the implant under the retina, the nozzle remains in a fixed position to the retina. During surgery, the surgeon places the nozzle in the retina prior to opening, but does not insert it into the retina. By actuating the actuator, the implant is pushed by the plunger out of the delivery opening of the nozzle through the opening in the retina under the retina. In this case, the instrument is preferably not in contact with the retina.

During insertion of the implant, this is clearly visible to the surgeon as long as it is outside the retina. In this phase it is thus still possible for the surgeon to align the implant in order to place it more accurately. Only when the implant is completely under the retina, this is no longer clearly visible to the surgeon. However, a substantially prolonged visibility of the implant can be achieved by not inserting the nozzle of the instrument according to the invention into the retina. This feature also makes it possible to reduce the risk of trauma to the surrounding tissue.

The suitability of the instrument according to the invention for the subretinal insertion of implants was demonstrated using the example of vitality detection of RPE cultured on polyester membranes (optionally encapsulated in gelatin) as well as subretinal implantation studies in rabbits.

It is preferred that the cross-section of the nozzle is oval, in particular in the region of the distal end piece of the nozzle. An oval shape of the outer cross section of the nozzle reduces the risk of trauma during the procedure, since the nozzle has no sharp edges, especially at its distal end.

It is preferred that only the distal end portion of the nozzle has an oval cross section while a proximal portion of the nozzle, for example, may have a round cross section. Thus, it is possible to manufacture the nozzle from a circular metal tube, the end of which has been flattened and has an oval cross-section. The flattened distal end of the nozzle may for example have a length of 6-7 millimeters and be angled relative to the proximal portion.

In a preferred embodiment, the nozzle has at least one pressure equalization opening, which is arranged proximally of the dispensing opening. This pressure compensation opening may be, for example, a circular or otherwise shaped bore which is arranged in the side of the nozzle. In the case of an oval nozzle, one side of one of the flat sides of the nozzle is designated. Preferably, at least one pressure compensation opening is arranged on each side of the oval cross section of the nozzle.

It is also possible for the nozzle to have at least two pressure compensation openings of different sizes, which in particular are both arranged on the same side of the oval cross section of the nozzle. Thus, the nozzle on each of its flattened sides, for example, have two pressure equalization openings, on one side of the pressure compensation openings may have a different diameter. For example, the larger of the two pressure compensation openings may be arranged proximal to the smaller one.

By means of said pressure compensation openings, it is possible to prevent the implant from being driven back into the nozzle of the implant during the implantation. Such a repulsion of the implant could, for example, by the infusion pressure caused during the surgical procedure. This infusion pressure is caused by the need to intraocularly introduce a fluid under pressure during surgery to avoid collapse of the eye. By means of said pressure compensation openings, this pressure can escape from the nozzle without causing the implant to drive back into the nozzle.

Furthermore, the loading and unloading of the instrument with the implant can be simplified by the pressure compensation openings. When loading and unloading forms around the implant a liquid bubble, which affects the feed of the piston in the nozzle. By the pressure equalization openings, a pressure relief can be created by the liquid is discharged from this bubble. Furthermore, a centrifugal or wall-directed liquid movement during the sliding process can be produced by the pressure equalization openings within the nozzle, whereby the implant is held stable in its position, preferably in the vicinity of the nozzle inner wall.

Furthermore, it is preferable that the discharge opening of the nozzle is formed obliquely. This is possible because the lower side of the nozzle extends distally further than the upper side of the nozzle. In other words, the distal end of the nozzle is not at a right angle, but preferably at an acute angle to the longitudinal direction of the nozzle. This allows an improved view of the surgeon on the implant. The shorter upper side of the nozzle allows a view of the implant while still being guided by the lower side of the nozzle and the side walls. The surgeon can thus already during this phase of the procedure check the orientation of the implant and adjust if necessary, before it is actually introduced into the retina.

In a preferred embodiment, the nozzle of the instrument has a loading opening in addition to the dispensing opening and to the at least one pressure equalization opening. The loading opening is arranged laterally at the distal end of the nozzle. Through this loading opening, the implant can be loaded into the nozzle and then discharged through the piston from the discharge opening. Without the loading opening, the implant is loaded through the discharge opening in the nozzle and then returned through this.

Distal to such a loading opening, the nozzle may have a portion in which its cavity is covered by a cover and thus completely enclosed. It is thus formed by a loading tray for receiving the implant, whereby the implant can be mechanically protected. This is especially important when passing the instrument through the sclera, as this would damage the implant. Preferably, the instrument has a locking device, with which the piston can be determined in a position such that the implant is held in said loading compartment, so that it can be protected from mechanical damage. When this locking device is released, the implant can be dispensed through the delivery port. In this fixing device may be a locking device, in particular a Rastarretierung.

During an intervention where an implant is inserted subretinally into an eye, it is necessary to maintain the intraocular pressure as it escapes through one or more openings in the ocular body that are necessary for the procedure. For this purpose, an infusion liquid is administered intraocularly with a definable pressure. This is done via appropriate infusion cannulas, which are introduced into the eye of the patient.

A disadvantage of known infusion cannulas is that they radiate the fluid in the direction of the retina, as a result of which it can be damaged.

It is an object of an independent invention to provide an infusion device for intraocular infusion of a fluid, by which the risk of trauma can be reduced.

The solution of this object is achieved by the features of claim 8.

The infusion device according to the invention has an infusion cannula and a stop plate, wherein the infusion cannula extends in the distal direction, starting from the stop plate. According to the invention, the infusion cannula has two outlet openings on two opposite sides for dispensing the liquid. In this case, the outlet openings are arranged and formed such that the liquid leaves the cannula at an angle of> 30 °, in particular 40 ° -50 °, measured from the longitudinal direction of the cannula, out of each outlet opening. The outlet openings are preferably arranged at a right angle to the longitudinal direction of the infusion cannula, wherein the angle at which the liquid exits the outlet opening depends on the pressure of the liquid.

In this way it can be avoided that the liquid impinges directly on the retina, for example at a right angle, and thus can injure it. Furthermore, by the said formation of the infusion cannula a collapse of the artificial retinal detachment, which is a prerequisite for a successful implantation can be prevented.

In a preferred embodiment of the infusion device, the distal end of the infusion cannula is conically rounded or dome-shaped. In this way, in addition a possible injury of the retina can be avoided by the distal end of the infusion cannula. Previously known infusion cannulas could not have a conical rounding at their distal end, as this would reduce the diameter of the outlet opening. This would lead to an increase in the flow rate, which would damage the retina.

The invention further relates to a system for subretinal insertion of an implant into a human or animal eye, the system comprising an instrument according to the present patent application and an infusion device according to the present patent application.

In the following, preferred embodiments of the invention will be explained with reference to figures. Show it:

1 A first embodiment of the instrument according to the invention

2 A second embodiment of the instrument according to the invention

3 , a-d: Different views of the nozzle of an embodiment of the instrument according to the invention.

4 , a-d: Different views of the nozzle of the second embodiment of the instrument according to the invention

5 , a-b: An embodiment of the infusion cannula according to the invention.

According to 1 shows the instrument 10 a holding part 14 to hold the instrument 10 by an operator. Distal to the holding part closes a nozzle 16 on, which has a cavity for receiving the implant, not shown 12 having. At the distal end of the nozzle 16 there is a discharge opening 18 to dispense the implant 12 , The instrument 10 also has a piston 20 on, through which the implant 12 from the discharge opening 18 the nozzle 16 is herausdrückbar. This piston is for example in 3b visible, noticeable.

According to 1 is the nozzle 16 in relation to the holding part 14 not displaceable and thus arranged stationary. The piston 20 is on the other hand by the actuator 22 opposite the holding part 14 inside the nozzle 16 displaceable, thereby pressing out the implant 12 from the discharge opening 18 the nozzle 16 he follows.

A second embodiment of the instrument according to the invention 10 is in 2 shown. As in the 4a D is recognizable, this second embodiment has a side loading opening 26 in addition to the discharge opening 18 and in addition to the pressure equalization opening 24a on. Through the side loading opening 26 The implant can be placed laterally in the nozzle 16 getting charged. For this purpose, the locking screw 28 be solved, so that it is possible, the locking mechanism together with the nozzle 16 in the distal direction relative to the holding part 14 to move. In this position, the loading opening 26 so opposite the piston 20 moved in the distal direction that the piston 20 the loading opening 26 completely releases, while previously partially in the loading opening 26 protruded. Thus, the implant can be freely inserted laterally into the loading opening. After that, the nozzle can 16 together with the screw 28 be moved back in the proximal direction, after which the screw 28 can be determined again. Now it is possible the actuator 22 to operate, so that the piston 20 another piece distally within the nozzle 16 is moved. The actuator 22 can be operated until the locking tongue 30 in a recess 32 locks. By this locking device, it is possible to define exactly how far the actuator is actuated in this position. Hereby can be defined how far the piston 20 inside the nozzle 16 is displaced in the distal direction. This happens so far that the piston 20 holds the implant in a loading compartment that extends below the in 4b illustrated cover 34 located. This allows the implant, for example, during the passage of the instrument 10 protected by the sclera from mechanical damage. Will the locking or locking device 30 . 32 Solved, the implant can pass through the delivery port 18 be issued.

Also in the second embodiment of the inventive instrument is preferably carried out during the dispensing of the implant from the nozzle 16 no displacement of the nozzle in relation to the holding part 14 , The nozzle 16 is thus during dispensing of the implant 12 from the nozzle 16 in relation to the holding part 14 Fixedly arranged and it shifts only the piston 20 inside the nozzle 16 ,

The first embodiment of the instrument 10 according to 1 does not have such a locking device.

According to 3a is the issue opening 18 the nozzle 16 oval shaped. It can have an outer width of 1.32 mm and an inner width of 1.1 mm. The distal bore 24a , in the 3b can be shown to have a diameter of 0.25 mm, while the proximal bore 24b may have a diameter of 0.5 mm. The piston 20 who in 3b a little bit from the nozzle 16 protrudes, may have a width of 0.8 mm.

According to 3c is the distal end of the nozzle 16 opposite the longitudinal direction of the nozzle 16 bent by 25 °. It may also have a thickness of 0.5 mm. The height of the discharge opening 18 can be 0.3 mm. The pressure compensation openings 24c . 24d at the bottom of the nozzle 16 (please refer 3d ) can have a diameter of 0.25 mm each.

The loading opening 26 , in the 4a shown may have a length of 2.45 mm. Its proximal end can be 5.7 mm from the distal end of the nozzle 16 are located away.

It is preferred that the distal end of the nozzle 16 is bevelled. In the position where the piston 20 furthest out of the nozzle 16 it protrudes 0.15 mm out of the nozzle.

According to 5a has the infusion device according to the invention 110 an infusion cannula 112 and a stop plate 114 on. In this case, the infusion cannula extends 112 starting from the stop plate 114 in the distal direction. The infusion cannula 114 has two outlet openings on two opposite sides 116a . 116b for dispensing the liquid. The outlet openings are arranged opposite one another and designed such that the liquid leaves each outlet opening of the infusion cannula at an angle of more than 30 °, in particular at an angle between 40 ° and 50 °, to the longitudinal direction of the infusion cannula. The distal end 112a the infusion cannula 112 is conically rounded or cup-shaped.

When using the instrument according to the invention 10 and the infusion device according to the invention 110 The following steps are performed. The infusion cannula 112 is introduced into the patient's eye to maintain intraocular pressure. For this purpose, the inside of the eye over the two outlet openings 116a . 116b Liquid supplied. The actual implantation is done by having the surgeon use the instrument 10 through the sclera leads to the retina, in the previously an opening was cut. By pushing out the piston 20 from the nozzle 16 the implant is out of the delivery port 18 pushed through the opening in the retina under the retina. Subsequently, the instrument 10 removed from the eye. It is preferred that the implantation takes place transvitreally.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 29819018 U1 [0007]
• EP 0967919 B1 [0008]
• WO 00/76403 A1 [0008]

Cited non-patent literature

• Binder S, Stanzel BV, Cancer I, Glittenberg C. Transplantation of the RPE in AMD. Prog Retin Eye Res 2007; 26: 516-554 [0004]
• Bhatt NS, Newsome DA, Fenech T, et al. Experimental transplantation of human retinal pigment epithelial cells on collagen substrates. On J Ophthalmol 1994; 117: 214-221 [0006]

Claims (9)

Instrument for subretinal insertion of an implant ( 12 ) into a human or animal eye, comprising: a holding part ( 14 ) for holding the instrument ( 10 ) by an operator, a nozzle ( 16 ) with a cavity for receiving the implant ( 12 ) and with a discharge opening ( 18 ) for the output of the implant ( 12 ), a piston ( 20 ) for pushing out the implant ( 12 ) from the discharge opening ( 18 ) of the nozzle ( 16 ), an actuator ( 22 ) for actuating the piston ( 20 ) by an operator, characterized in that the nozzle ( 16 ) in relation to the holding part ( 14 ) is stationary and the piston ( 20 ) by the actuator ( 22 ) opposite the holding part ( 14 ) within the nozzle ( 16 ) is displaceable, so that thereby pushing out of the implant ( 12 ) from the discharge opening ( 18 ) of the nozzle ( 16 ) he follows. Instrument according to claim 1, characterized in that the cross section of the nozzle ( 16 ) is oval. Instrument according to one of claims 1 or 2, characterized in that the nozzle ( 16 ) at least one pressure equalization opening ( 24a - 24d ) proximal to the dispensing opening (FIG. 18 ) is arranged. Instrument according to claims 2 and 3, characterized in that on each side of the oval cross-section of the nozzle ( 16 ) at least one pressure equalization opening ( 24a - 24d ) is arranged. Instrument according to claim 3, characterized in that the nozzle ( 16 ) at least two pressure compensation openings ( 24a . 24b ) of different sizes, in particular both on the same side of the oval cross section of the nozzle ( 16 ) are arranged, wherein the larger of the two pressure compensation openings is arranged in particular proximally of the smaller. Instrument according to one of claims 1 to 5, characterized in that the dispensing opening ( 18 ) of the nozzle ( 16 ) is formed obliquely, characterized in that the underside of the nozzle ( 16 ) in the distal direction than the upper side of the nozzle ( 16 ). Instrument according to claim 6, characterized by a loading opening ( 26 ) in addition to the dispensing opening ( 18 ) and to the at least one pressure equalization opening ( 24a - 24d ), the loading opening ( 26 ) laterally at the distal end ( 16a ) of the nozzle ( 16 ) is arranged. Infusion device for the intraocular infusion of a fluid during an eye surgery, comprising - an infusion cannula ( 112 ), - a stop plate ( 114 ), whereby the infusion cannula ( 112 ) starting from the stop plate ( 114 ) extends in the distal direction, the infusion cannula ( 114 ) on two opposite sides two outlet openings ( 116a . 116b ) for dispensing the liquid, wherein the outlet openings ( 116a . 116b ) are arranged and formed such that the liquid from each outlet opening the infusion cannula ( 112 ) at an angle of 30 °, in particular at an angle between 40 ° and 50 °, measured to the longitudinal direction of the infusion cannula ( 112 ) leaves. Instrument according to claim 8, characterized in that the distal end ( 112a ) of the infusion cannula ( 112 ) is conically rounded or dome-shaped.

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