Ophthalmological implant and method for producing an ophthalmological implant

Abstract

The invention relates to an ophthalmological implant (10), comprising a layer system (16) having at least one layer (12) made of a first material and having at least one functional layer (14) made of a second material. The functional layer (14) can be switched from a first state into a second state by means of a magnetic and / or electromagnetic and / or chemical stimulus (S), wherein at least one optical parameter of the implant (10) from the group consisting of dioptre and focality is different in the first and in the second state. The invention also relates to a method for producing such an ophthalmological implant (10).

Description

[0001] Ophthalmic implant and procedure for manufacturing an ophthalmic implant

[0002] The invention relates to an ophthalmic implant with a switchable functional layer and a method for manufacturing such an ophthalmic implant.

[0003] Multifocal intraocular lenses have been developed by many medical technology companies in recent years to offer selected patient groups a better visual experience. Despite careful patient selection for these types of products, some patients are dissatisfied with the implanted intraocular lens. In the worst-case scenario, the ophthalmic implant even needs to be replaced in a second procedure. Two of the main reasons for this are adverse effects associated with the design of multifocal implants, such as aberrations and glare.

[0004] It would be desirable not only to have a non-invasive treatment option for patients who need to have their multifocal lens removed, but also to give more patients the opportunity to try multifocal concepts or premium lenses without having to fear that a second operation will be necessary afterward. Likewise, it would be desirable to be able to adjust the diopter value of an implant later without a further invasive procedure, if necessary.

[0005] Several methods for correcting the optical outcome of multifocal lenses have been theoretically described in the literature, and some have even been demonstrated in practice. For example, WO 2014 / 077983 A2 discloses a method for modifying the optical power of an intraocular lens (IOL) in a patient's eye after implantation using a laser system. This method locally alters the hydrophilicity of the polymer material from which the IOL is made, i.e., at the point of laser application, thus modifying the optical properties of the lens after surgery. The method is compatible with a wide range of different polymeric biomaterials used for IOLs. When an acrylic-based material is exposed to guided irradiation, existing ester groups are cleaved into a carboxyl and a hydroxyl compound.The former remains covalently bound to the polymer backbone, while the latter is cleaved off as a separate alcohol. This leads to the release of the alcohol and a reduction in (electronic) density, as well as increased local water uptake due to the formation of polar carboxyl groups. Both effects result in a local decrease in the refractive index. If the laser dose is correctly directed into the lens in all three dimensions, a phase correction pattern can be created within the existing lens to modify its optical properties. In this way, a change in diopter or toricity can be achieved, and the multifocality of a lens can also be eliminated by a corresponding pattern generated inside a multifocal IOL.

[0006] This procedure, however, requires complex and expensive equipment that must be provided and used by the surgeon. Furthermore, the conversion must be performed with high energy doses over a period of several minutes to generate the phase correction pattern required to eliminate the multifocality of the implanted lens. During this time, the laser must be precisely aligned, and the patient must be immobilized accordingly. To calculate the correct phase correction pattern and align the laser accurately, the patient's eye must be examined, the lens position determined, and the implanted lens model known. After evaluating this fundamental data, the calculations can then be performed to obtain a promising correction pattern. If the target is not correctly achieved, the entire procedure must be repeated, or the implant may ultimately need to be surgically replaced.

[0007] From EP 3273 294 A1 and US 2007 / 052920 A1, ophthalmic implants with liquid crystal areas are known that can be switched by electric current to change the optical properties of the implant. However, these implants are problematic because they require electrical components and contacts as well as a power source connected to the implant.

[0008] The object of the present invention is therefore to provide an ophthalmic implant that allows for simpler, faster, and more reliable subsequent modification of its optical properties. A further object of the invention is to provide a means of manufacturing such an ophthalmic implant.

[0009] The problems are solved according to the invention by an ophthalmological implant having the features of claim 1 and by a method according to claim 8 for manufacturing such an ophthalmological implant. Advantageous embodiments with expedient further developments of the invention are specified in the respective dependent claims, wherein advantageous embodiments of one aspect of the invention are to be regarded as advantageous embodiments of the other aspect of the invention.

[0010] A first aspect of the invention relates to an ophthalmic implant which enables a simpler, faster and more reliable subsequent modification of its optical properties by comprising a layer system with at least one layer of a first material and with at least one functional layer of a second material, wherein the functional layer can be switched from a first state to a second state by means of a magnetic and / or electromagnetic and / or chemical stimulus and wherein at least one optical parameter of the implant from the group diopter and focality is different in the first and second states.In other words, the invention provides that the ophthalmic implant has a layered system with two or more layers, wherein at least one of the layers consists of an active second material that is not distributed within the first material but exists as a separate functional layer and can be switched postoperatively from a first to a second state by initialization using a preferably external stimulus, thereby changing the focality and / or the diopter value of the implant. The other layer of the first material is not a functional layer, meaning that it does not change its properties in response to the stimulus. This allows the aforementioned optical parameters of the implant to be changed particularly quickly, easily, and reliably.The implant can be "switched" because no complex local modifications within the entire volume of the implant are required; instead, only the properties of the entire functional layer need to be switched by initialization using the stimulus. In some embodiments, the implant's layer system can include one or more additional non-switchable layers, which may also consist of the first material or of other materials. Furthermore, it is possible to provide two or more functional layers, with different functional layers being switchable by the same stimulus or by different stimuli. A single functional layer and one or two layers are preferred. The first and second materials can consist independently of each other of a single compound or a single compound type, or of a mixture of two or more compounds.Preferably, the implant according to the invention is configured as an intraocular lens. The implant comprises at least one optical part, which includes the layer system or preferably consists of the layer system. In embodiments, one or more haptic parts may be provided, which may also be formed from the layer system or consist of separate materials. Generally, "one" or "a" within the scope of this disclosure is to be read as an indefinite article, i.e., unless expressly stated otherwise, always also as "at least one" or "at least one". Conversely, "one" or "a" may also be understood as "only one" or "only one".

[0011] In an advantageous embodiment of the invention, the ophthalmic implant is multifocal in one state and monofocal in the other. Preferably, the implant is multifocal in the first state, which is present at the beginning or after implantation, and can then be switched to the second, monofocal state if problems arise with the multifocality. This allows for a significant reduction in photopsia such as halos and glare, as well as a marked increase in contrast, in problematic cases. If the patient experiences no problems with the implant, which is the norm, switching to the second state can advantageously be omitted entirely. However, the reverse is also possible, meaning that the implant is initially monofocal in the first state and can be switched to the second, multifocal state at the patient's request.This provides a quick, simple, and reliable way to allow the patient to try a multifocal lens if desired. Alternatively or additionally, the ophthalmic implant is designed to have a diopter difference of at least 0.2 D, particularly at least 0.5 D, and preferably at least 1.0 D, between the first and second states. This offers a correspondingly quick, simple, and reliable way to adjust the implant's diopter value by a specific amount, which can be positive or negative, after implantation to better tailor the implant's optical properties to the patient's needs.

[0012] In an advantageous embodiment of the invention, the first material is a hydrophilic or hydrophobic lens material. This allows the basic properties of the implant to be optimally adapted to the respective application. Alternatively or additionally, the second material is a polymer material that can be chemically modified by means of a stimulus, thereby changing its refractive index in the wavelength range visible to humans (approximately 400 nm to approximately 780 nm) and / or its water absorption capacity. This allows the optical properties of the implant to be modified particularly easily and reliably. All parameters mentioned in this disclosure are generally determined under standard conditions, i.e., at an ambient temperature of 20 °C and an ambient pressure of 1 bar, unless otherwise specified.Alternatively or additionally, a further embodiment provides that the second material possesses at least substantially the same refractive index (n) as the first material only in one of the states. In other words, it is provided that the first and second materials possess the same or at least substantially the same refractive index (preferably An ± 0.3) only in the first state or only in the second state, while exhibiting a correspondingly different refractive index (preferably |An|>0.3) in the other state. This represents a particularly simple technical possibility of selectively producing either substantially the same optical properties in one of the states or different optical properties in the other state.

[0013] In a further advantageous embodiment of the invention, the layer has a refractive monofocal profile and the functional layer has a multifocal profile that is either diffractive or refractive. In this case, the layer preferably forms an outer shell of the implant, while the functional layer forms an inner layer that can then generate multifocality in one state or be optically "switched off" in the other state to bring it to the same refractive index as the layer and thereby generate monofocality. In a preferred embodiment, the functional layer has a diffractive multifocal profile, whereas in a less preferred embodiment, the functional layer may also have a refractive multifocal profile. In an alternative embodiment, the layer has a diffractive multifocal profile and the functional layer has a diffractive profile.The preferably inner functional layer also provides a diffractive profile, which is "switched off" (same refractive index) in one state and can be activated in the other state to cancel or compensate for the diffractive profile of the shell. This provides various design concepts for the implant according to the invention, from which a choice can be made as needed.

[0014] In a further advantageous embodiment of the invention, the layer forms an optical zone of the implant and the functional layer does not extend over the entire optical zone. This allows for the creation of a partially diffractive lens. Alternatively or additionally, the functional layer is reversibly switchable between the first and second states. In other words, the change in the state of the functional layer is not permanent but can be reversed. This is a particularly advantageous way to reverse a change in the optical properties of the implant if it has not yielded the desired results. It is also possible to change the optical properties of the implant after a considerable period of time since implantation, for example, if the visual acuity of the patient's eye has changed significantly.

[0015] Further advantages arise from the functional layer incorporating embedded magnetic particles, particularly nanoparticles. This allows a magnetic stimulus to be advantageously used to switch the functional layer. Preferably, the particles are super-paramagnetic nanoparticles, for example made of Fe3Ü4, in order to avoid impairing the optical properties of the functional layer while still being able to respond to a magnetic stimulus to a sufficient degree for switching.

[0016] In a further advantageous embodiment of the invention, the stimulus is non-electrical and / or is selected from the group consisting of UV light irradiation, visible light irradiation, IR light irradiation, electromagnetic pulses, injection of a chemical stimulus, and eye drops containing an enzymatic stimulus. In other words, the switching of the state of the functional layer of the ophthalmic implant is effected by non-electrical means, with possible stimuli being light of various wavelength ranges, electromagnetic pulses, or chemical substances that can be applied, for example, by injection or as eye drops.

[0017] The use of a non-electrical stimulus means that no electrical components or contacts are required, either inside or outside the implant, to switch the functional layer. This simplifies implant design, reduces the risk of defects from electrical components, and eliminates the need for a power supply for switching. A choice of different types of light irradiation, electromagnetic pulses, or chemical stimuli offers flexibility in how switching can be initiated, allowing for adaptation to various clinical requirements and patient preferences. The application of chemical stimuli in the form of eye drops represents a particularly patient-friendly and minimally invasive method for inducing switching.Overall, the use of a non-electrical stimulus enables simplified, reliable, and patient-friendly control of the optical properties of the ophthalmic implant. For the purposes of this disclosure, UV radiation is understood to mean wavelengths in the range of approximately 10 nm to approximately 380 nm, in particular from approximately 280 nm to approximately 380 nm (UV-B to UV-A). Visible light is understood to mean wavelengths visible to humans in the range of approximately 380 nm to approximately 750 nm. IR radiation accordingly includes wavelengths from approximately 750 nm to 1 mm or longer, in particular near-infrared in the range of 750 nm to 1400 nm.

[0018] A second aspect of the invention relates to a method for manufacturing an ophthalmic implant in which a layered system is produced comprising at least one layer of a first material and at least one functional layer of a second material, wherein the functional layer can be switched from a first state to a second state by means of a magnetic and / or electromagnetic and / or chemical stimulus, and wherein at least one optical parameter of the implant from the group consisting of diopters and focality differs between the first and second states. This allows the aforementioned optical parameters of the implant to be changed or "switched" particularly quickly, easily, and reliably, since no complex local modifications within the entire volume of the implant are necessary; rather, only the properties of the entire functional layer are switched by initialization using the stimulus.They can be modified. Further features and their advantages can be found in the descriptions of the first aspect of the invention.

[0019] In an advantageous embodiment of the invention, the first layer of the layer system is produced from the first material, after which the second material, in a flowable form, is applied to the first layer, cured to form the functional layer, and optionally post-processed. This layer-by-layer approach allows for particularly precise adjustment of the properties of the layer(s) or functional layer(s) of the layer system. Furthermore, established turning and milling processes for multifocal IOLs can be advantageously reused. The application of the second material can be achieved, for example, by casting, embossing, or coating with a pre-polymer.

[0020] Depending on the geometric complexity and desired materials, it is alternatively possible to produce the layer and the functional layer independently and then bond them together, for example, by adhesive bonding. This approach is particularly suitable in the case of rigid hydrophilic (meth)acrylates as the first and / or second material. After bonding the individual layer(s) and functional layer(s), a final machining step, preferably involving subtraction, can be performed on the entire layer system or the entire implant to create the correct dimensions or a specific surface profile.

[0021] In another alternative manufacturing process, two layers of the first material are produced, after which the second material, in a flowable form, is introduced between the two layers and cured to form the functional layer. For this purpose, an injection molding process can be used, for example, whereby the two layers can advantageously act as a kind of mold for the injected functional layer.

[0022] Further features of the invention are evident from the claims, the figures, and the description of the figures. The features and combinations of features mentioned above in the description, as well as those subsequently mentioned in the description of the figures and / or shown in the figures alone, are not only usable in the combinations specified, but also in other combinations without departing from the scope of the invention. Thus, embodiments that are not explicitly shown and explained in the figures, but which can be derived and generated from the explained embodiments by separate combinations of features, are also to be considered as encompassed and disclosed by the invention. Embodiments and combinations of features that do not exhibit all the features of an originally formulated independent claim are also to be considered disclosed.Furthermore, embodiments and combinations of features, in particular those set out above, are to be considered disclosed which go beyond or deviate from the combinations of features set out in the cross-references of the claims. This shows:

[0023] Fig. 1 shows a schematic sectional view of an ophthalmic implant according to the invention, which is switched from a multifocal state to a monofocal state by means of a stimulus;

[0024] Fig. 2 shows a schematic representation of a method for switching the ophthalmic implant according to the invention;

[0025] Fig. 3 shows a schematic representation of an alternative method for manufacturing the ophthalmic implant according to the invention with a three-layer system;

[0026] Fig. 4 shows a schematic representation of a further alternative method for manufacturing the ophthalmic implant according to the invention with a three-layer system; Fig. 5 shows a schematic sectional view of an alternative embodiment of the ophthalmic implant according to the invention with a two-layer system;

[0027] Fig. 6 shows a schematic representation of a further alternative method for manufacturing the ophthalmic implant according to the invention with a three-layer system;

[0028] Fig. 7 shows a schematic representation of another alternative method for manufacturing the ophthalmic implant according to the invention with a three-layer system;

[0029] Fig. 8 shows a reaction equation for the photochemical cleavage of 1-(4-methoxy-5-alkoxy-2-nitrophenyl)alkyl acetate

[0030] Fig. 9 shows a reaction equation for the photochemical cleavage of (6-bromo-7-hydroxy-2-oxo-2H-chromen-4-yl)alkyl acetate

[0031] Fig. 10 shows a reaction equation for the reversible dimerization of alkyl cinnamic acid esters;

[0032] Fig. 11 shows a reaction equation for the reversible dimerization of coumarin; and

[0033] Fig. 12 shows a reaction equation for the reversible dimerization of anthracene.

[0034] Fig. 1 shows a schematic sectional view of an ophthalmic implant 10 according to the invention, which is configured here as an intraocular lens (IOL). The IOL 10 comprises two passive layers 12 made of a first hydrophobic or hydrophilic material and an active functional layer 14 made of a second material, wherein the functional layer 14 can be switched from a first state to a second state by means of a stimulus S (see Fig. 2) as indicated by arrow 1a. The stimulus S can be a magnetic and / or electromagnetic and / or chemical stimulus S. The layers 12 and the functional layer 14 together form a layer system 16. In the first state (left), the IOL 10 is multifocal, since the functional layer 14 has a different refractive index (n) than the layers 12 and the layers 12 and the functional layer 14 each have diffractive interfaces with each other.The stimulus S changes the refractive index of the functional layer 14, so that it now corresponds, at least substantially, to the refractive index of the surrounding layers 12. This effectively eliminates the diffractive interfaces between the layers 12 and the functional layer 14, and the focality of the IOL 12 changes, making it monofocal (see Fig. 1, right). In certain embodiments, the diopter value of the IOL 10 may also change, for example, due to a change in the volume of the functional layer 14 resulting from altered water absorption. Preferably, the switching is irreversible. However, in some embodiments, it may be desirable for the IOL to be able to switch back from the second state to the first state. This reversible switching back to the first state is symbolized by arrow Ib in Fig. 1.

[0035] Fig. 2 shows a schematic representation of a method for switching the ophthalmic implant 10 according to the invention. From top to bottom, an IOL 10 with two layers 12, which have multifocal refractive profiles, is first provided. The upper layer 12 forms the lens front. The functional layer 14 is located between the layers 12. In a first state, the functional layer 14 has the same refractive index as the layers 12. Subsequently (arrow Ha), the functional layer 14 is switched to the second state by the stimulus S. According to arrow Hb, this can lead to a change in the refractive index with at least substantially an unchanged layer thickness of the functional layer 14, whereby, in this case, a phase correction pattern is created within the IOL 10 that compensates for the multifocal pattern of the upper layer 12.Alternatively, in the second state, the water absorption capacity of the functional layer 14, and thus the water content and the dimension of the functional layer 14, can change, which in the present case also creates a phase correction pattern within the IOL 10 and also changes the diopter value of the IOL 10.

[0036] To manufacture the IOL 10, the lower layer 12 can first be produced and optionally provided with a desired profile. The lower layer 12 is then coated with the functional layer 14, after which the upper layer 12 is applied to the functional layer 14 and optionally finished on the outside. Fig. 3 shows a schematic representation of an alternative method for manufacturing the ophthalmic implant 10 according to the invention with a three-layer system 16. From top to bottom, a layer 12 made of a first hydrophilic or hydrophobic material is first provided. The layer 12 is then processed, for example by turning, to create a first optical surface (Illa). The functional layer 14 is then produced by applying a second material to the layer 12 (Illb).Initially, in the example shown, functional layer 14 has the same refractive index n as layer 12. Functional layer 14 is then also processed to create a second optical surface (Ille). Finally, an optional additional layer 12 is applied (II Id). The resulting IOL 10 is thus "activated" in the sense that switching functional layer 14 from the first to the second state shown activates the two internal optical surfaces, which are initially ineffective due to the identical refractive index of functional layer 14 and layer 12. Since both the initial and subsequent optical profiles are already "programmed" into the implant 10, switching functional layer 14 requires less precision and time than if the desired optical profile had to be completely "written" into the volume of the IOL 10 using a laser, as was previously the case.The surgeon also does not need to use an expensive and complex activation system. This concept can, in principle, be integrated into all multifocal lenses, thus lowering the threshold for their use and providing the surgeon with an easy-to-use "fallback system" to make quick and precise changes to the optical properties afterward.

[0037] Fig. 4 shows a schematic representation of a further alternative method for manufacturing the ophthalmic implant 10 according to the invention with a three-layer system 16. The principle corresponds to that of the preceding embodiment. In contrast to the embodiment shown in Fig. 3, the functional layer 14 has a different refractive index n than the layers 12 from the outset, i.e., in the first state. The resulting IOL 10 is thus "deactivatable" in the sense that by switching the functional layer 14 from the first to the second state shown, the two inner optical surfaces, which are initially effective due to the different refractive index n of functional layer 14 and layers 12, are deactivated and no longer cause light refraction.

[0038] Fig. 5 shows an alternative embodiment of the ophthalmic implant 10 according to the invention with a two-layer system 16. This embodiment may be sufficient in some applications and depending on the desired optical profile, so that a third or further layers 12 / 14 can be omitted. On the left is an IOL 10 in which the functional layer 14 has the same refractive index as layer 12 in the first state, while in the right example of the IOL 10, the functional layer 14 has a different refractive index than layer 12 in the first state. The left IOL 10 is thus designed to be "activated" in the sense described above, while the right IOL is designed to be "deactivated". The active functional layer 14 is therefore not located in the middle of the system 16, but on one of the outer surfaces of the IOL 10.The number of integrated active functional layers 14 and passive layers 12 per IOL 10 can also be changed and does not necessarily have to be one or two.

[0039] Fig. 6 shows a schematic representation of another alternative method for manufacturing the ophthalmic implant 10 according to the invention with a three-layer system 16. In contrast to the previous embodiment, the two layers 12 are first produced with the respective desired profiles. The second material for the functional layer 14 is introduced in a flowable state between the layers 12, and the functional layer 14 is created by embossing. For this purpose, the upper layer 12 is pressed towards the lower layer 12, as indicated by arrow VI, whereby both layers 12 "imprint" their profiles into the second material and form the functional layer 14. Finally, the second material is optionally cured.

[0040] Fig. 7 shows a schematic representation of another alternative method for manufacturing the ophthalmic implant 10 according to the invention with a three-layer system 16. Here, the two layers 12 are again provided with a desired profile and arranged with a gap relative to each other. The second material is then introduced into the gap by casting or die casting, as indicated by arrow VII, and hardens to form the functional layer 14. The two layers 12 thus form a kind of mold for the functional layer 14.

[0041] The active functional layer 14 can, in some configurations, contain photosensitive monomers or polymers. Reversible and irreversible systems are available for this purpose. As already mentioned, the chemical system for the implant 10 described here does not necessarily have to be reversible, but it can be. A reversible switch between the first and second states allows the multifocal profile to be switched on and off, so to speak. In the following, some possible chemical groups suitable for realizing the switchable functional layer 14 are discussed as examples. These chemical groups can be modifications of a base polymer or, as monomers or prepolymers, possibly together with other ingredients as a second material.

[0042] Figure 8 shows a reaction equation for the photochemical cleavage of 1-(4-methoxy-5-alkoxy-2-nitrophenyl)alkyl acetate, where Ri and R2 can be chosen independently and can be monomers or part of a polymer matrix. The original ester group is cleaved into an acid and a ketone, thereby changing the water absorption capacity and the refractive index. Both reaction products may optionally remain covalently bound to a polymer matrix. This applies generally and regardless of the specific functional group.

[0043] Fig. 9 shows a reaction equation for the photochemical cleavage of (6-bromo-7-hydroxy-2-oxo-2H-chromen-4-yl)alkyl acetate. This functional group can also be used for the realization of the functional layer 14, since the water absorption capacity and the refractive index can also be modified with this group.

[0044] Fig. 10 shows a reaction equation for the reversible dimerization of alkyl cinnamic acid esters. This functional group can therefore be used to produce a functional layer 14 that can be reversibly switched between the first and second states. The same applies to coumarin, which is reversibly dimerizable according to the reaction equation shown in Fig. 11, and to anthracene, which is also reversibly dimerizable according to the reaction equation shown in Fig. 12. As an alternative to a photochemical process, chemical cleavage of polymeric crosslinkers or side groups can also be used to produce the second material. The application of the desired chemical compound can be triggered either inside the polymer material (similar to a drug-eluting IOL) or administered externally, the latter being non-invasive (e.g., via eye drops) or minimally invasive (e.g., via injection).The previously discussed magnetic activation can also be provided for.

[0045] All described implants 10 and layer systems 16 are characterized by a complete optical transformation of the functional layer 14. The intention is not to locally change the refractive index within the active functional layer 14, but rather to establish two discrete states with different optical properties into which the entire functional layer 14 can be placed. The advantages of this approach are that no expensive laser system is required for activation. A simple illumination or magnetization system is sufficient. Consequently, no particularly precise guidance of the activation system (e.g., laser) is needed to generate the stimulus S for switching, resulting in a faster processing time and, due to the significantly simpler switching process, a lower probability of errors.Furthermore, the previously required high energy doses can be avoided for the patient, and the treatment time itself can be significantly shorter (depending on the selected stimulus type). The implant 10 according to the invention already possesses pre-fabricated optical profiles, which are at least inherently provided by the manufacturer and merely need to be activated or deactivated, but do not need to be generated de novo. This guarantees a particularly reliable result and reduces the complexity on the part of the surgeon. The stimulus S, or trigger, for the active functional layer 14 can be selected for both the surgeon and the patient in accordance with the chemical properties of the conversion system and within a suitable range of different workflow options.

[0046] The system described here is not limited to switching between monofocal and multifocal lenses. It can also be used to incorporate an optical pattern that can be activated to shift the diopters of the IOL 10 up or down by a predefined value (e.g., ±1.0 D). While refractive errors can also be corrected in this way, a significant advantage is that a multifocal IOL 10 can be tried with less risk, as it can be converted back to a standard monofocal lens 10 if problems arise, without requiring a second surgical explantation procedure. All the described stimuli share the common features of not requiring additional ocular biometry, not needing to be aligned as precisely as previously required, and therefore delivering a significantly faster, simpler, and more reliable result.

[0047] Differently designed systems can be provided for switching such an ophthalmic implant 10, which are configured to generate the stimulus S and switch at least one functional layer 14 from the first state to the second state, such that at least one optical parameter of the implant 10 from the group of diopters and focality changes. This allows the aforementioned optical parameters of the implant 10 to be changed or "switched" particularly quickly, easily, and reliably, since no complex local changes within the entire volume of the implant 10 are necessary; instead, only the properties of the entire functional layer 14 are switched by initialization using the stimulus S.

[0048] Depending on the design of the implant 10, a suitable system for switching between the first and second states can comprise means for generating a magnetic and / or electromagnetic and / or chemical stimulus S. In other words, the system can generate a stimulus S or trigger, where the stimulus S can be magnetic, electromagnetic (e.g., UV, Vis, IR light irradiation, electromagnetic pulses (analogous to liquid crystals)), or chemical (e.g., an injection or eye drops with an enzymatic stimulus). For a magnetic stimulus S, for example, superparamagnetic nanoparticles (e.g., FeaCL) can be embedded in the implant 10 or in the functional layer 14. In this case, the second material is preferably a thermally sensitive polymer or comprises a thermally sensitive polymer whose refractive index changes irreversibly depending on the temperature.Alternatively, the activation or switching of the functional layer 14 can be effected by irradiation with wavelengths preferably outside the visible spectrum (< 400 nm / > 700 nm, especially > 780 nm), with UV radiation being preferred, particularly UV-A (380-315 nm) and preferably UV-B (315-280 nm) to prevent accidental switching of the functional layer 14 by sunlight. In this case, the second material should be correspondingly photosensitive, i.e., preferably containing photosensitive monomers, polymers, and / or polymer formation blocks. As already mentioned, the switching between the two states can be permanent or reversible, depending on the chemical configuration of the second material. Permanent, irreversible switching generally ensures a higher degree of safety, since the implant 10 is inert to further stimuli S after the initial switching process.A change in the refractive index n can be caused, for example, by a structural change in an organic aromatic system, by a change in the water absorption capacity of the polymer, or by a combination of both. A local increase in water absorption can be achieved, for example, by releasing more hydrophilic groups such as carboxyl groups or by deprotecting hydrophilic groups protected by a protecting group, for example, by cleaving ester groups. A system tailored to the implant 10 possesses independent inventive quality and represents a separate inventive aspect.

[0049] The parameter values ​​specified in the documentation for defining process and measurement conditions for characterizing specific properties of the invention are also to be considered as included in the scope of the invention, even in the event of deviations – for example, due to measurement errors, system errors, weighing errors, DIN tolerances, and the like. Reference numeral list

[0050] 10 ophthalmic implants

[0051] 12 layers, 14 functional layers

[0052] 16-shift system

[0053] S Stimulus

Claims

Patent claims 1. Ophthalmic implant (10) comprising a layer system (16) with at least one layer (12) made of a first material and with at least one functional layer (14) made of a second material, characterized in that the functional layer (14) can be switched from a first state to a second state by means of a magnetic and / or electromagnetic and / or chemical stimulus (S) and wherein at least one optical parameter of the implant (10) from the group diopter and focality is different in the first and second state.

2. Ophthalmic implant (10) according to claim 1, characterized in that it is multifocal in one of the states and monofocal in the other of the states and / or that it has a diopter difference in magnitude of at least 0.2 D, in particular at least 0.5 D and preferably at least 1.0 D between the first and the second state.

3. Ophthalmic implant (10) according to claim 1 or 2, characterized in that the first material is a hydrophilic or hydrophobic lens material and / or that the second material is a polymer material which is chemically modifiable by means of the stimulus (S) and changes its refractive index in the wavelength range visible to humans and / or its water absorption capacity and / or that the second material has at least substantially the same refractive index as the first material in only one of the states.

4. Ophthalmic implant (10) according to one of claims 1 to 3, characterized in that the layer (12) has a refractive monofocal profile and the functional layer has a multifocal profile which is diffractive or refractive, or that the layer (12) has a diffractive multifocal profile and the functional layer (14) has a diffractive profile.

5. Ophthalmic implant (10) according to one of claims 1 to 4, characterized in that the layer (12) forms an optical zone of the implant (10) and the functional layer (14) does not extend over the entire optical zone and / or that the functional layer (14) is reversibly switchable between the first state and the second state.

6. Ophthalmic implant (10) according to one of claims 1 to 5, characterized in that the functional layer (14) has embedded magnetic particles, in particular nanoparticles.

7. Ophthalmic implant (10) according to one of claims 1 to 6, characterized in that the stimulus (S) is non-electrical and / or that the stimulus (S) is selected from the group consisting of UV light irradiation, Vis light irradiation, IR light irradiation, electromagnetic pulses, injection of a chemical stimulus (S) and eye drops containing an enzymatic stimulus (S).

8. Method for producing an ophthalmic implant (10) in which a layer system (16) is produced which has at least one layer (12) of a first material and at least one functional layer (14) of a second material, characterized in that the functional layer (14) can be switched from a first state to a second state by means of a magnetic and / or electromagnetic and / or chemical stimulus (S) and wherein at least one optical parameter of the implant (10) from the group diopter and focality is different in the first and second state.

9. The method of claim 8, wherein to produce the layer system (16) the layer (12) is produced from the first material, after which the second material is applied to the layer (12) in flowable form, cured and optionally post-processed; or the layer (12) and the functional layer (14) are produced independently of each other and then joined together; or two layers (12) are produced from the first material, after which the second material is introduced in flowable form between the two layers (12) and cured to form the functional layer (14).

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