Syringe for an eye operation, having a viscoelastic chamber and a decomposition reagent chamber

Abstract

The invention relates to a syringe (1) for an eye operation, having a syringe body (3), a plunger (4) which is arranged in the syringe body so as to be displaceable in the syringe longitudinal direction (5), a viscoelastic chamber (6) in which a viscoelastic is arranged, and a decomposition reagent chamber (7) which is arranged separately from the viscoelastic chamber (6) and in which a decomposition reagent is arranged, which is designed to decompose the viscoelastic, wherein the syringe (1) has a storage state, in which the viscoelastic and the decomposition reagent are arranged separately from one another, and a use state, into which the syringe (1) is able to be put by longitudinally displacing the plunger (4) and in which the viscoelastic and the decomposition reagent are mixed with one another.

Description

[0001] Syringe for eye surgery, with a

[0002] Viscoelastic chamber and a decomposition reagent chamber

[0003] The invention relates to a syringe for eye surgery, the syringe having a viscoelastic chamber and a decomposition reagent chamber.

[0004] During eye surgery, particularly cataract treatment, a viscoelastic is traditionally inserted into the eye. The viscoelastic may comprise, for example, sodium hyaluronate. The viscoelastic may be a high-viscosity cohesive viscoelastic, which is used to maintain space within the eye and to build up pressure, for example, to dilate the iris of the eye before capsulorhexis is performed. The viscoelastic can also be a low-viscosity dispersive viscoelastic, which wets surfaces within the eye to protect these surfaces from injury during eye surgery. The viscoelastic must be removed from the eye at the end of eye surgery because the viscoelastic can block the trabecular meshwork of the eye, causing an increase in pressure inside the eye.The low-viscosity dispersive viscoelastic particularly wets the cornea and the chamber angle of the eye. Because these areas are difficult to reach with an aspiration probe, the low-viscosity dispersive viscoelastic is difficult to remove from the eye. It is known to inject hyaluronidase into the eye. Hyaluronidase is a reagent that decomposes sodium hyaluronate. This makes it necessary, however, to provide a syringe containing the hyaluronidase during eye surgery and to insert the syringe into the eye to inject the hyaluronidase. This represents an additional step that has to be carried out by a doctor performing the eye surgery, which makes the operation complex. The object of the invention is therefore to provide a syringe with which eye surgery is less complex.

[0005] The syringe according to the invention for an eye operation has a syringe body, a piston, a viscoelastic chamber and a decomposition reagent chamber. The piston is arranged in the syringe body so as to be displaceable in a longitudinal direction of the syringe. A viscoelastic is arranged in the viscoelastic chamber. The decomposition reagent chamber is arranged separately from the viscoelastic chamber and in the decomposition reagent chamber there is arranged a decomposition reagent which is designed to decompose the viscoelastic. The syringe has a storage state in which the viscoelastic and the decomposition reagent are arranged separately from one another and a use state in which the syringe can be brought by longitudinally displacing the piston and in which the viscoelastic and the decomposition reagent are mixed with one another.

[0006] The syringe according to the invention eliminates the need to provide a separate syringe for the decomposition reagent; instead, the syringe according to the invention provides both the viscoelastic and the decomposition reagent. This makes eye surgery using the syringe less complex. In the stored state, the viscoelastic and the decomposition reagent are prevented from mixing, thereby preventing decomposition of the viscoelastic in the stored state. A mixture of the viscoelastic and the decomposition reagent is only created when the piston is displaced longitudinally from the stored state, and thus only shortly before the mixture is injected into the eye. This allows the viscoelastic to still fulfill its function in the eye before the viscoelastic is decomposed by the decomposition reagent.

[0007] It is preferred that the viscoelastic comprises hyaluronic acid and / or a salt of hyaluronic acid and the decomposition reagent comprises hyaluronidase and / or that the viscoelastic comprises hydroxypropylmethylcellulose and the decomposition reagent comprises a cellulase, in particular an exoglucanase and / or an endoglucanase.

[0008] The syringe preferably has a cannula, via which the viscoelastic and the decomposition reagent can be displaced out of the syringe by longitudinally displacing the plunger in the longitudinal direction of the syringe. In particular, the mixture of the viscoelastic and the decomposition reagent can be displaced out of the cannula.

[0009] It is preferred that the syringe body has a partition wall, wherein the viscoelastic chamber and the decomposition reagent chamber are arranged next to one another in a direction perpendicular to the longitudinal direction of the syringe and are separated from one another by the partition wall. It is particularly preferred that the syringe has a mixing chamber which is arranged such that the viscoelastic and the decomposition reagent enter the mixing chamber when the piston is displaced in the longitudinal direction of the syringe. The viscoelastic and the decomposition reagent can mix in the mixing chamber and thus form the mixture. It is conceivable that in the storage state the mixing chamber is free of the viscoelastic and / or the decomposition reagent.This can be achieved, for example, if the syringe has a viscoelastic closure by means of which flow of the viscoelastic into the mixing chamber is prevented when the syringe is in the storage state, and which can be opened by displacing the piston in the longitudinal direction of the syringe starting from the storage state, and / or if the syringe has a decomposition reagent closure by means of which flow of the decomposition reagent into the mixing chamber is prevented when the syringe is in the storage state, and which can be opened by displacing the piston in the longitudinal direction of the syringe starting from the storage state. Alternatively or additionally, it is conceivable that air or another gas is arranged in the mixing chamber in the storage state, which prevents the viscoelastic and / or the decomposition reagent from entering the mixing chamber.

[0010] It is preferred that the mixing chamber be arranged such that the viscoelastic and the decomposition reagent exit the mixing chamber together and then enter the cannula when the piston is displaced in the longitudinal direction of the syringe. Thus, with respect to a flow direction produced by displacing the piston in the longitudinal direction of the syringe, the mixing chamber is located downstream of the viscoelastic chamber, downstream of the decomposition reagent chamber, and upstream of the cannula.

[0011] As an alternative to providing the mixing chamber, it is conceivable for the viscoelastic and the decomposition reagent to enter the cannula together, where the mixture is formed. In another example, in which the mixing chamber is also not provided, it is conceivable for the cannula to have a first line into which the viscoelastic enters when the piston is moved in the longitudinal direction of the syringe, and a second line into which the decomposition reagent enters when the piston is moved in the longitudinal direction of the syringe, the cannula being designed such that the mixture is only formed after the viscoelastic and the decomposition reagent have exited the cannula.

[0012] The syringe preferably has a tip region and a body region, wherein the tip region can be detachably coupled to the body region, in particular by means of a thread or in that the tip region is mounted on the body region in a longitudinally displaceable manner, wherein the mixing chamber is arranged in the tip region and the viscoelastic chamber and the decomposition reagent chamber are arranged in the body region.

[0013] The piston preferably has a first partial piston which is designed to displace the viscoelastic out of the viscoelastic chamber, and a second partial piston which is arranged separately from the first partial piston and is designed to displace the decomposition reagent out of the decomposition reagent chamber. It is particularly preferred that the second partial piston has a predetermined breaking point. By breaking the second partial piston at the predetermined breaking point, it is possible to remove the broken-off part of the second partial piston from the injector body. If the piston is then displaced in the longitudinal direction of the syringe, only the viscoelastic is displaced out of the cannula.

[0014] The syringe preferably has a plug which is arranged in the injector body so as to be displaceable in the longitudinal direction of the syringe and which can be driven thereto from outside the injector body, the decomposition reagent chamber and the viscoelastic chamber being arranged one after the other in the longitudinal direction of the syringe. In other words, with respect to a flow direction which is brought about by displacing the piston in the longitudinal direction of the syringe, the viscoelastic chamber is arranged downstream of the decomposition reagent chamber. Furthermore, the viscoelastic chamber and the decomposition reagent chamber are separated from one another by means of the plug which delimits a line by means of which the viscoelastic can flow from the viscoelastic chamber into the decomposition reagent chamber and the decomposition reagent can flow from the decomposition reagent chamber into the viscoelastic chamber.By moving the stopper in the longitudinal direction of the syringe, the viscoelastic or the decomposition reagent flows in the line against the longitudinal direction of the syringe and mixes with the decomposition reagent or the viscoelastic after exiting the line. By moving the stopper in the longitudinal direction of the syringe, the viscoelastic or the decomposition reagent flows in the longitudinal direction of the syringe and mixes with the decomposition reagent or the viscoelastic after exiting the line. By moving the stopper several times in the longitudinal direction of the syringe and against the longitudinal direction of the syringe, the viscoelastic and the decomposition reagent can be mixed particularly well.

[0015] The plug preferably has a valve configured to block the line in the storage state and to open the line when a pressure difference between the viscoelastic chamber and the decomposition reagent chamber is exceeded. This prevents the viscoelastic and the decomposition reagent from mixing even in the storage state.

[0016] It is preferred that the piston be formed by an outer piston and an inner piston, which is mounted longitudinally displaceably within the outer piston, with the plug being attached either to the outer piston or to the inner piston. This makes it particularly easy to drive the plug from outside the injector body in the syringe's longitudinal direction and counter to the syringe's longitudinal direction.

[0017] The viscoelastic chamber is preferably arranged in the syringe longitudinal direction between the cannula and the decomposition reagent chamber.

[0018] The invention is explained in more detail below with reference to the attached schematic drawings.

[0019] Figure 1 shows a longitudinal section through a first embodiment of the syringe, with a first embodiment of a viscoelastic chamber and a decomposition reagent chamber of the syringe,

[0020] Figure 2 is a perspective view of a second embodiment of the viscoelastic chamber and the decomposition reagent chamber,

[0021] Figure 3 is a perspective view of a third embodiment of the viscoelastic chamber and the decomposition reagent chamber, Figure 4 is a perspective view of the first embodiment of the viscoelastic chamber and the decomposition reagent chamber and

[0022] Figure 5 shows a longitudinal section through a second embodiment of the syringe.

[0023] As can be seen from Figures 1 and 5, a syringe 1 for an eye operation has a syringe body 3, a piston 4, a viscoelastic chamber 6 and a decomposition reagent chamber 7. The piston 4 is arranged in the syringe body 3 so as to be displaceable in a syringe longitudinal direction 5. A viscoelastic is arranged in the viscoelastic chamber 6. The decomposition reagent chamber 7 is arranged separately from the viscoelastic chamber 6, and a decomposition reagent which is designed to decompose the viscoelastic is arranged in the decomposition reagent chamber 7. The syringe 1 has a storage state in which the viscoelastic and the decomposition reagent are arranged separately from one another and in particular in their respective chambers 6, 7, and a use state in which the syringe 1 can be brought by a longitudinal displacement of the piston 4 and in which the viscoelastic and the decomposition reagent are mixed with one another.By displacing the piston 4 in the syringe's longitudinal direction 5, starting from the storage state, a mixture can be produced within the syringe 1, which mixture comprises the viscoelastic and the decomposition reagent and in particular consists of the viscoelastic and the decomposition reagent. In particular, the syringe 1 can be designed such that no mixing of the viscoelastic and the decomposition reagent occurs in the storage state. The syringe 1 can be configured to subsequently inject the mixture into the eye. The term "use state" refers to the syringe in any state of the syringe in which the piston 4 has been displaced in the syringe's longitudinal direction 5, starting from the storage state.The viscoelastic may comprise hyaluronic acid and / or a salt of hyaluronic acid, and the decomposition reagent may comprise hyaluronidase, and / or the viscoelastic may comprise hydroxypropylmethylcellulose, and the decomposition reagent may comprise a cellulase, in particular an exoglucanase and / or an endoglucanase. The hyaluronidase is configured to decompose the hyaluronic acid and / or the salt of hyaluronic acid. The cellulase is configured to decompose the hydroxypropylmethylcellulose. The viscoelastic may be free of the decomposition reagent, and the decomposition reagent may be free of the viscoelastic.

[0024] It is conceivable for the viscoelastic to be in liquid form. In a first exemplary solution which forms the viscoelastic, the hyaluronic acid and / or the salt of hyaluronic acid can be dissolved in a solvent, such as water, for example. The salt of hyaluronic acid can be sodium hyaluronate, for example. The sodium hyaluronate can, for example, have an average molar mass in a range from 0.5 to 4 MDa, in particular in a range from 0.5 to 1.5 MDa. The concentration of the sodium hyaluronate in the first solution can, for example, be in a range from 0.5% by mass to 4.0% by mass, in particular in a range from 2.0% by mass to 4.0% by mass. The viscoelastic may additionally contain auxiliary substances, such as a pH buffer, in particular a phosphate buffer, NaCl, lidocaine, NaOH, sodium bicarbonate and / or antioxidants.In a second exemplary solution which forms the decomposition reagent, the hydroxypropylmethylcellulose can be dissolved in a solvent, such as water. The hydroxypropylmethylcellulose can, for example, have an average molar mass in a range from 10 kDa to 2000 kDa, in particular in a range from 50 kDa to 500 kDa. The concentration of the hydroxypropylmethylcellulose in the viscoelastic can, for example, be in a range from 0.5 mass% to 4.0 mass%, in particular in a range from 1.0 mass% to 3.0 mass%. The viscoelastic can additionally comprise excipients, such as a pH buffer, in particular a phosphate buffer, NaCl, lidocaine, NaOH, sodium bicarbonate and / or antioxidants.

[0025] It is conceivable that the decomposition reagent is in liquid form. For example, in a third exemplary solution forming the decomposition reagent, the hyaluronidase can be dissolved in a solvent, such as water. The concentration of the hyaluronidase in the third solution can be in a range from 0.1 to 10 U / ml, in particular in a range from 0.5 to 2 U / ml. The decomposition reagent can additionally contain excipients, such as a pH buffer, in particular a phosphate buffer. In a fourth exemplary solution forming the decomposition reagent, the cellulase can be dissolved in a solvent, such as water. The concentration of the cellulase in the decomposition reagent can be in a range from 0.1 to 20 U / ml, in particular in a range from 0.5 to 5 U / ml.The decomposition reagent may additionally contain auxiliary substances, such as a pH buffer, in particular a phosphate buffer.

[0026] It is also conceivable for the decomposition reagent to be a mixture of the first solution and the second solution. The volume ratio of the first solution to the second solution can, for example, be in a range from 1:100 to 100:1, in particular in a range from 1:10 to 10:1. In the case where the decomposition reagent is the mixture of the first solution and the second solution, it is conceivable for the decomposition reagent to be a mixture of the third solution and the fourth solution. The volume ratio of the third solution to the fourth solution can, for example, be in a range from 1:100 to 100:1, in particular in a range from 1:10 to 10:1.The volume ratio of viscoelastic and decomposition reagent in the syringe 1 can be adjusted so that an increase in viscosity in the eye caused by injecting the viscoelastic is reduced by 15% to 60%, in particular by 25% to 50%, within 5 to 15 minutes.

[0027] Figures 1 and 5 show that the syringe 1 can have a cannula 2, via which the viscoelastic and the decomposition reagent can be displaced out of the syringe 1 by longitudinally displacing the piston 4 in the syringe's longitudinal direction 5. When the flow direction of the viscoelastic and / or the decomposition reagent is changed by displacing the piston 4 in the syringe's longitudinal direction 5, the cannula 2 is arranged downstream of the viscoelastic chamber 6 and downstream of the decomposition reagent chamber 7.

[0028] According to a first embodiment of the syringe 1 shown in Figures 1 and 4, the syringe body 3 can have a partition wall 16, wherein the viscoelastic chamber 6 and the decomposition reagent chamber 7 are arranged next to one another in a direction perpendicular to the syringe longitudinal direction 5 and are separated from one another by means of the partition wall 16.

[0029] Figure 1 shows that the syringe 1 can have a mixing chamber 8 which is arranged such that the viscoelastic and the decomposition reagent enter the mixing chamber 8 when the piston 4 is moved in the longitudinal direction 5 of the syringe. The mixture can therefore be formed in the mixing chamber 8. In addition, the mixing chamber 8 can be arranged such that the viscoelastic and the decomposition reagent exit the mixing chamber 8 together and then enter the cannula 2 when the piston 4 is moved in the longitudinal direction 5 of the syringe, i.e. the mixing chamber 8 is arranged downstream of the viscoelastic chamber 6, downstream of the decomposition reagent chamber 7 and upstream of the cannula 2 with respect to the flow direction. The mixing chamber 8 can have a first mixing chamber opening 17, by means of which the mixing chamber 8 is fluidly connected to the viscoelastic chamber 6 in the use state.The mixing chamber 8 can have a second mixing chamber opening 18, by means of which the mixing chamber 8 is fluidically connected to the decomposition reagent chamber 7 in the use state. It is conceivable that the first mixing chamber opening 17 is arranged at a distance from the second mixing chamber opening 18. The mixing chamber 8 can have a third mixing chamber opening 19, by means of which the mixing chamber 8 is fluidically connected to the cannula 2. The third mixing chamber opening 19 can be arranged at a distance from the first mixing chamber opening 17 and the second mixing chamber opening 18.

[0030] It is conceivable for the syringe 1 to have a viscoelastic seal, by means of which the flow of the viscoelastic from the viscoelastic chamber 6 into the mixing chamber 8 is prevented when the syringe 1 is in the storage state. The viscoelastic seal can be opened by displacing the piston 4 in the longitudinal direction 5 of the syringe, starting from the storage state. This can ensure that no mixing of the viscoelastic and the decomposition reagent takes place in the storage state. Alternatively or additionally, it is conceivable that the syringe 1 has a decomposition reagent closure by means of which a flow of the decomposition reagent from the decomposition reagent chamber 7 into the mixing chamber 8 is prevented when the syringe 1 is in the storage state, wherein the decomposition reagent closure can be opened by displacing the piston 4 in the syringe longitudinal direction 5 starting from the storage state.

[0031] The syringe 1 can have a tip region 9 and a body region 10, wherein the tip region 9 can be detachably coupled to the body region 10, the mixing chamber 8 being arranged in the tip region 9 and the viscoelastic chamber 6 and the decomposition reagent chamber 7 being arranged in the body region 10. In Figure 1, the boundary between the tip region 9 and the body region 10 is indicated by the dashed line. In order to detachably couple the tip region 9 to the body region 10, the syringe 1 can, for example, have a thread or the tip region 9 can be arranged on the body region 10 so that it can be displaced longitudinally.

[0032] It is conceivable that the cross-section of the decomposition reagent chamber 7 in a plane whose normal is arranged parallel to the syringe longitudinal direction 5 is smaller than the cross-section of the viscoelastic chamber 6 in the plane . This allows the decomposition reagent to be provided with a smaller volume than the viscoelastic. In particular, the cross-section of the decomposition reagent chamber 7 is less than or equal to 50% of the cross-section of the viscoelastic chamber 6.

[0033] As can be seen from Figures 1 and 2, the piston 4 can have a first partial piston 11, which is designed to displace the viscoelastic out of the viscoelastic chamber 6, and a second partial piston 12, which is arranged separately from the first partial piston 11 and is designed to displace the decomposition reagent out of the decomposition reagent chamber 7. The first partial piston 11 can delimit the viscoelastic chamber 6 and the second partial piston 12 can delimit the decomposition reagent chamber 7. It is conceivable for the piston 4 to have a thumb rest 15, which forms the end of the piston 4 facing away from the viscoelastic chamber 6. The first partial piston 11 and the second partial piston 12 can be fastened to the thumb rest 15. As a result, by pressing the thumb rest 15, the first partial piston 11 and the second partial piston 12 can be moved simultaneously.It is conceivable for the first partial piston 11 to have a first piston thickening 13 which forms the end of the first partial piston 11 facing away from the thumb rest 15. It is also conceivable for the second partial piston 12 to have a second piston thickening 14 which forms the end of the second partial piston 12 facing away from the thumb rest 15. It is conceivable for the second partial piston 12 to have a predetermined breaking point. The second partial piston 12 can be broken at the predetermined breaking point and a section of the second partial piston 12 which has the longitudinal end of the second partial piston 12 facing away from the thumb rest 15 can be removed from the injector body 2. As an alternative to providing the predetermined breaking point, it is also conceivable that the second partial piston 12 is not directly or indirectly attached to the thumb rest 15, but only the first partial piston 12 is attached to the thumb rest 15, whereby the second partial piston 12 can be removed from the in ector body 2.It is also conceivable for the thumb rest 15 to have a through-hole through which the second partial piston 12 extends. In this case, the second partial piston 12 can have a locking mechanism which has an unlocking state in which the second partial piston 12 can slide through the through-hole, and a locking state in which the second partial piston 12 is fastened to the thumb rest 15. In the locking state, only the viscoelastic is pressed out of the syringe 1 by longitudinal displacement of the piston 4, whereas in the unlocking state, the viscoelastic and the decomposition reagent are pressed out of the syringe 1 by longitudinal displacement of the piston 4. This means that, for example, the viscoelastic can be injected first on its own and later the viscoelastic can be injected together with the decomposition reagent.For example, the locking mechanism can be formed by teeth on the second partial piston 12, which do not engage the thumb rest 15 in the unlocked state and engage the thumb rest 15 in the locked state. For example, the teeth can be brought into engagement by rotating the second partial piston 12.

[0034] Figures 1 and 4 show a first embodiment of the viscoelastic chamber 6 and the decomposition reagent chamber 7, in which the decomposition reagent chamber 7 is not enclosed by the viscoelastic chamber 6, but is arranged completely laterally of the viscoelastic chamber 6 in a direction transverse to the syringe longitudinal direction 5. Figure 2 shows a second embodiment of the viscoelastic chamber 6 and the decomposition reagent chamber 7, in which the viscoelastic chamber 6 encloses the decomposition reagent chamber 7. Figure 3 shows a third embodiment of the viscoelastic chamber 6 and the decomposition reagent chamber 7, in which a plurality of decomposition reagent chambers 7 is provided. It is conceivable that a respective one of the second partial pistons 12 is provided for each of the decomposition reagent chambers 7.

[0035] According to a second embodiment of the syringe 1 shown in Figure 5, the syringe 1 can have a plug 23 which is arranged in the injector body 3 so as to be displaceable in the syringe longitudinal direction 5 and can be driven therefrom from outside the injector body 3, wherein the decomposition reagent chamber 7 and the viscoelastic chamber 6 are arranged one after the other in the syringe longitudinal direction 5. In other words, with respect to a flow direction which is brought about by displacing the piston 4 in the syringe longitudinal direction 5, the viscoelastic chamber 6 is arranged downstream of the decomposition reagent chamber 7.In addition, the viscoelastic chamber 6 and the decomposition reagent chamber 7 are separated from one another by means of the plug 23, which delimits a line 24, by means of which the viscoelastic can flow from the viscoelastic chamber 6 into the decomposition reagent chamber 7 and the decomposition reagent can flow from the decomposition reagent chamber 7 into the viscoelastic chamber 6. The plug 23 can have a valve 28, which is designed to block the line 24 in the storage state and to open the line 24 when a pressure difference between the viscoelastic chamber 6 and the decomposition reagent chamber 7 is exceeded. The syringe 1 is thus designed such that no mixing of the viscoelastic and the decomposition reagent takes place in the storage state. If the pressure in the viscoelastic chamber 6 is higher than the pressure in the decomposition reagent chamber 7 by a first pressure difference, the valve 28 opens the line 24.If the pressure in the decomposition reagent chamber 7 is higher than the pressure in the viscoelastic chamber 6 by a second pressure difference, the valve 28 opens the line 24. It is conceivable that the first pressure difference is equal to the second pressure difference. Alternatively, it is also conceivable that the valve 28 is a film that tears when a pressure difference between the viscoelastic chamber 6 and the decomposition reagent chamber 7 is exceeded.

[0036] Figure 5 shows that the piston 4 can be formed by an outer piston 21 and an inner piston 22, which is mounted so as to be longitudinally displaceable within the outer piston 21, the plug 23 being fastened to the inner piston 22. Alternatively, it is conceivable that the plug 23 is fastened to the outer piston 21. By fastening the plug 23 to the inner piston 22 or to the outer piston 23, the plug 23 can be driven from outside the injector body 2 in the longitudinal direction 5 of the syringe or against the longitudinal direction 5 of the syringe. It is conceivable that the outer piston 21 has an outer piston thumb rest 29, which is a thickening of the outer piston 21 at the longitudinal end of the outer piston 21 facing away from the cannula 2.In addition, the inner piston 22 can have an inner piston thumb rest 30, which is a thickening of the inner piston 22 at the longitudinal end of the inner piston 22 facing away from the cannula 2 and which is arranged outside the outer piston 21 in the storage state and in the use state.

[0037] The line 24 can have a first sub-line 25 and a second sub-line 26, which communicate with that of the viscoelastic chamber 6 and the decomposition reagent chamber 7, which is arranged on the side of the plug 23 facing away from the cannula 2. The first sub-line 25 and the second sub-line 26 can open in a direction arranged perpendicular to the longitudinal direction 5 of the syringe, on different sides of the inner piston 22, into that of the viscoelastic chamber 6 and the decomposition reagent chamber 7, which is arranged on the side of the plug 23 facing away from the cannula 2, see Figure 5. In addition, the line 24 can have a third partial line 27 which opens into that of the viscoelastic chamber 6 and the decomposition reagent chamber 7, which opens on the side of the plug 23 facing the cannula 2, wherein the first partial line 25 and the second partial line 26 open into the third partial line 27.The valve 28 can be arranged in the third partial line 27.

[0038] The viscoelastic chamber 6 can be arranged in the syringe longitudinal direction 5 between the cannula 2 and the decomposition reagent chamber 7, see Figure 5 .

[0039] By now displacing the stopper 23 in the syringe longitudinal direction 5 by means of the inner piston 22, the viscoelastic flows against the syringe longitudinal direction 5 through the line 24 into the decomposition reagent chamber 7 and mixes there with the decomposition reagent. It is conceivable that the outer piston 21 is displaced against the syringe longitudinal direction 5 in order to compensate for the volume of the inner piston 21 in the viscoelastic chamber 7. If the stopper 23 is then displaced against the syringe longitudinal direction 5 by means of the inner piston 22, the mixture of the viscoelastic and the decomposition reagent flows in the syringe longitudinal direction 5 through the line 24 into the viscoelastic chamber 6. At the same time, the outer piston 21 can be displaced in the syringe longitudinal direction 5 to compensate for the volume of the inner piston 22 in the decomposition reagent chamber 7. List of reference symbols

[0040] 1 syringe

[0041] 2 cannulas

[0042] 3 syringe bodies

[0043] 4 pistons

[0044] 5 Syringe longitudinal direction

[0045] 6 Viscoelastic chamber

[0046] 7 Decomposition reagent chamber

[0047] 8 Mixing chamber

[0048] 9 top range

[0049] 10 Body area

[0050] 11 first partial piston

[0051] 12 second piston section

[0052] 13 first piston thickening

[0053] 14 second piston thickening

[0054] 15 Thumb rest

[0055] 16 Partition wall

[0056] 17 first mixing chamber opening

[0057] 18 second mixing chamber opening

[0058] 19 third mixing chamber opening

[0059] 21 outer bulbs

[0060] 22 inner pistons

[0061] 23 plugs

[0062] 24 line

[0063] 25 first sub-line

[0064] 26 second sub-line

[0065] 27 third sub-line

[0066] 28 Valve

[0067] 29 Outer piston thumb rest

[0068] 30 inner piston thumb rest

Claims

Patent claims 1. A syringe for an eye operation, comprising a syringe body (3), a piston (4) which is arranged in the syringe body (3) so as to be displaceable in a syringe longitudinal direction (5), a viscoelastic chamber (6) in which a viscoelastic is arranged, and a decomposition reagent chamber (7) which is arranged separately from the viscoelastic chamber (6) and in which a decomposition reagent is arranged which is designed to decompose the viscoelastic, wherein the syringe (1) has a storage state in which the viscoelastic and the decomposition reagent are arranged separately from one another, and a use state in which the syringe (1) can be brought by longitudinally displacing the piston (4) and in which the viscoelastic and the decomposition reagent are mixed with one another.

2. Syringe according to claim 1, wherein the viscoelastic comprises hyaluronic acid and / or a salt of hyaluronic acid and the decomposition reagent comprises hyaluronidase and / or wherein the viscoelastic comprises hydroxypropylmethylcellulose and the decomposition reagent comprises a cellulase, in particular an exoglucanase and / or an endoglucanase.

3. Syringe according to claim 1 or 2, wherein the syringe (1) has a cannula (2) via which the viscoelastic and the decomposition reagent can be displaced out of the syringe (1) by longitudinally displacing the piston (4) in the syringe longitudinal direction (5).

4. Syringe according to claim 3, wherein the syringe body (3) has a partition wall (16), wherein the viscoelastic chamber (6) and the decomposition reagent chamber (7) are arranged next to one another in a direction perpendicular to the syringe longitudinal direction (5) and are separated from one another by means of the partition wall (16).

5. Syringe according to claim 4, wherein the syringe (1) has a mixing chamber (8) arranged so that the viscoelastic and the decomposition reagent are introduced into the mixing chamber (8) occur when the piston (4) is displaced in the syringe longitudinal direction (5), in particular wherein the mixing chamber (8) is arranged such that the viscoelastic and the decomposition reagent emerge together from the mixing chamber (8) and then enter the cannula (2) when the piston (4) is displaced in the syringe longitudinal direction (5).

6. Syringe according to claim 5, wherein the syringe (1) has a tip portion (9) and a body portion (10), wherein the tip portion (9) is detachably connectable to the body portion (10), wherein the mixing chamber (8) is arranged in the tip region (9) and the viscolelastic chamber (6) and the decomposition reagent chamber (7) are arranged in the body region (10).

7. Syringe according to one of claims 4 to 6, wherein the piston (4) has a first partial piston (11) which is designed to displace the viscoelastic out of the viscoelastic chamber (6), and a second partial piston (12) which is arranged separately from the first partial piston (11) and is designed to displace the decomposition reagent out of the decomposition reagent chamber (7), in particular wherein the second partial piston (12) has a predetermined breaking point.

8. Syringe according to claim 3, wherein the syringe (1) has a plug (23) which is arranged displaceably in the syringe longitudinal direction (5) in the injector body (3) and is drivable thereto from outside the in ector body (3), wherein the decomposition reagent chamber (7) and the viscoelastic chamber (6) are arranged one after the other in the syringe longitudinal direction (5) and are separated from each other by means of the plug (23) which delimits a line (24) by means of which the viscoelastic is Viscoelastic chamber (6) can flow into the decomposition reagent chamber (7) and the decomposition reagent can flow from the decomposition reagent chamber (7) into the viscoelastic chamber (6).

9. Syringe according to claim 8, wherein the plug (23) has a valve (28) which is configured to block the line (24) in the storage state and to open the line (24) when a pressure difference between the viscoelastic chamber (6) and the decomposition reagent chamber (7) is exceeded.

10. Syringe according to claim 8 or 9, wherein the piston (4) is formed by an outer piston (21) and an inner piston (22) which is mounted longitudinally displaceably within the outer piston (21), wherein the plug (23) is attached either to the outer piston (21) or to the inner piston (22).

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