Surgical ophthalmic device for inserting intraocular lenses into eyes

Abstract

ophthalmic surgical device (1) with - a control device (3); - a user interface (5) which is at least temporarily in data communication with the control device (3); - a first measuring device (9) which is suitable and intended to determine intraoperatively at least one value (W1) that is characteristic of an eye to be treated surgically, - a second measuring device (7) which is suitable and intended to determine preoperatively and / or intraoperatively at least one value (W2) that is characteristic of the eye to be surgically treated, and with - a first computing unit (11) which is suitable and intended to determine at least one first output value (A1) that is characteristic of at least one intraocular lens (IOL) to be selected, using the intraoperatively determined value (W1) as well as the preoperatively and / or intraoperatively determined value (W2), wherein the user interface preferably has at least one output device (16) which is suitable for outputting the output value (A1) or a value derived therefrom; characterized by the fact that. the device (1) has a second computing unit (13) which is suitable and intended to determine, using the intraoperatively determined value (W1) and the preoperatively determined value (W2) on the basis of a model of the eye, at least one second output value (A2) which is characteristic of a postoperative refractive error of the eye.

Description

[0001] The present invention relates to an ophthalmic surgical device and a selection method for selecting a lens, in particular an intraocular lens. Many methods and devices are known in the art that serve to improve eye surgery, and in particular the insertion of intraocular lenses (IOLs) into eyes. For example, methods are known in which a patient's cloudy natural lens is surgically removed and replaced with an artificial lens (in particular an intraocular lens, IOL).

[0002] There are also known procedures in which an additional lens is inserted in addition to the existing natural lens to improve the eye's vision. A large number of highly diverse intraocular lenses are available on the market. Therefore, such operations always pose the challenge of selecting a suitable type of intraocular lens from a variety of options. These available intraocular lenses differ, for example, in their refractive index, the lens material used, the radii of curvature of the lens surfaces, the axial distance between the lens surfaces, the type of haptic, the diameter, and other properties.

[0003] Furthermore, there are different types of intraocular lenses, such as intraocular lenses with aspheric lens surfaces or lens surfaces that are freeform surfaces without rotational symmetry. Intraocular lenses with different zones or intraocular lenses with diffractive optical elements are also known.

[0004] To ensure a suitable IOL is implanted in a patient's phakic eye, it is possible to preselect an IOL with the appropriate refractive power to achieve the patient's desired postoperative target refraction. This approach predicts the postoperative position of the IOL, particularly in relation to a measured capsular bag position. These predictions can be used to better position and center the implanted IOL. Alternatively, a surgeon can be assisted in deciding whether to replace the implanted lens with an IOL that better fits the patient's eye.

[0005] It should be noted that the IOL is implanted first, and then – during the surgery – the eye's visual acuity is assessed. In these cases, it may be necessary to replace the IOL if the refractive power of the implanted IOL is not sufficient to achieve the desired postoperative target refraction of the patient's eye. Such an IOL replacement involves increased effort during cataract surgery. Furthermore, it can also lead to medical complications. Therefore, this procedure represents a quality control measure to determine whether an already selected IOL actually achieves the desired target refraction.

[0006] A previous patent application by the applicant with publication number EP 2 764 854 A2 discloses a method in which an intraocular lens is inserted into the eye. During the operation, intraoperative parameters of the eye are determined, which, if a postoperative visual defect is detected, are used to determine whether a different IOL should be selected and inserted in a subsequent step. This allows this different IOL to be selected more accurately according to the patient's requirements, improving the chances of success of the subsequent surgical procedure. However, the replacement of the previously inserted IOL and the associated risk of medical complications remain.

[0007] The present invention is therefore based on the object of providing a device and, if appropriate, also a method which avoid such an exchange of the IOL and which already enable a selection of an IOL to be inserted during an operation or which enable an intraoperative selection of the refractive power of an IOL so that the desired postoperative target refraction of the eye is achieved after its implantation.

[0008] This object is achieved according to the invention by a device according to claim 1. Advantageous embodiments and further developments are the subject of the subclaims.

[0009] An eye surgery device according to the invention has at least one control device and a user interface which is at least temporarily in data communication with the control device (i.e., can be at least partially brought into such data communication). Preferably, inputs can be entered into the control device via this user interface and / or information originating from or forwarded by the control device can be output. Furthermore, the eye surgery device has a first measuring device which is suitable and intended (or is configured and provided for this purpose) to determine (or ascertain) at least one value intraoperatively (i.e., during the operation on the eye in question) which is characteristic of an eye to be surgically treated.

[0010] In addition, the eye surgery device has a second measuring device which is suitable and intended to determine preoperatively and / or intraoperatively at least one value which is characteristic of the eye to be surgically treated.

[0011] Preferably, the second measuring device is intended for determining preoperative values; however, it would also be conceivable for only intraoperatively determined values ​​to be measured. Preferably, however, several different values ​​are determined.

[0012] Furthermore, the eye surgery device comprises a first computing unit, which is suitable and intended to determine at least one first output value, which is characteristic of at least one intraocular lens to be selected, using the intraoperatively determined value as well as the preoperatively and / or intraoperatively determined value. Furthermore, the user interface preferably comprises at least one output device, which is suitable for outputting the output value or a value derived therefrom. This output device can be, for example, a display unit. However, it can also be designed separately or integrated into another device.

[0013] In this case, the at least one IOL to be selected, determined by at least one first output value, preferably represents the IOL determined (in particular during the operation) which is then inserted into the eye.

[0014] According to the invention, an eye surgery device is thus proposed by means of which the values ​​obtained intraoperatively are used to select a lens. In other words, it is conceivable that only one lens is preselected or a preselection is made before an operation, or that no lens is selected at all before the operation.

[0015] In this case, measurements of the eye are specifically determined, preferably before surgery (i.e., preoperatively). Furthermore, measurements are also taken intraoperatively, and then the measurements determined before surgery and the additional measurements, particularly those obtained intraoperatively on the aphakic eye, are used for calculations, for example, to incorporate them into an aphakic eye model, as described in more detail below. This eye model can be used, in particular, to model the refractive power of an IOL to be implanted or, in general, a lens to be implanted.

[0016] However, said measured values ​​can also be applied to a pseudophakic eye model, where this eye model already contains an IOL or still contains the natural lens. The results of this eye model allow the selection of a suitable IOL so that the desired postoperative target refraction is reliably achieved. This makes it possible, for example, for a user, such as a physician, to select a suitable IOL not before the operation, but during the operation, for example, immediately after phacoemulsification and the measurement value determination. Thus, within the scope of the invention, the IOL is selected intraoperatively and not preoperatively. In this way, the quality control described above can be dispensed with.

[0017] The control device described above can preferably perform different functions or be configured to do so. For example, this control device can be configured to read in preoperative (or preoperatively determined or measured) values ​​determined by the (second) measuring device. It can also be configured to read in intraoperative values ​​determined by the first measuring device. It should be noted that the first and second measuring devices can be the same measuring device, but (preferably) different measuring devices can also be used.

[0018] In addition, the control device can also be configured to cause the user interface to display a value that is characteristic of the intraocular lens. In addition, the control device can also be configured to cause at least one or both measuring devices to determine or ascertain intraoperative and / or preoperative values.

[0019] Furthermore, the control device is preferably configured to cause the first computing unit to determine a value that represents a visual impairment of the eye. In this case, the preoperative measured values ​​can preferably be assigned to a first subset of the aforementioned parameters of the model, and the intraoperative values ​​of the eye can preferably be assigned to a second subset of the plurality of parameters of the model.

[0020] Furthermore, the control device can be configured to cause the user interface to display the value that represents a visual impairment.

[0021] In a further advantageous embodiment, the user interface has input means for entering data. It is also conceivable that the control device is designed or configured such that it waits for a specific user input into the user interface before initiating the first and / or second measuring device to determine the preoperative values ​​and / or the intraoperative values.

[0022] In a further advantageous embodiment, the eye surgery device can also comprise a removal device for removing a natural lens of the eye. In a further advantageous embodiment, the preoperative values ​​are selected from a group of values ​​that includes a value representing a surface geometry or a thickness of the cornea of ​​the eye, a value representing a distance between a corneal vertex of the eye and a retina of the eye, and a value representing a distance between the corneal vertex of the eye and a lens of the eye. Advantageously, several of these values, and particularly preferably all of these values, are determined and / or taken into account.

[0023] It is also possible that these values ​​are measured and / or output by the first measuring device.

[0024] In addition, it would also be possible for the first measuring device to also determine a value that represents a distance between a corneal vertex and an intraocular lens or is characteristic thereof and / or a value that is determined based on at least one incision made in the cornea of ​​the eye and / or a value that represents a centration of an intraocular lens in the eye.

[0025] Several of these values ​​can also be output. The IOL to be used can be not only monofocal, but also bifocal or multifocal, or have a variable refractive power. Such accommodative IOLs are known in the state of the art. See, for example, M. Bergemann's dissertation: "New Mechatronic System for Restoring the Accomodation Capability of the Human Eye" (2007, ISBN: 978-3-86644-136-1), pp. 20 to 21. However, it is advantageous if a desired postoperative target refraction is achieved at the lower and upper limits of the variable IOL refractive power, so that the IOL's variability can be optimally utilized.

[0026] In a further advantageous embodiment, the proposed device also comprises an optimization algorithm and / or a module for manufacturing an IOL. Using such an optimization algorithm, the geometry of an IOL can then be optimized, as is known from the optimization of optical systems using software packages, so that the eye model provides the desired postoperative target refraction as a parameter. This geometric data can then be forwarded to a module for manufacturing an IOL. This module can be, for example, a 3D printer or a device for turning (plastic) lenses.

[0027] Furthermore, it would also be possible to pre-select an IOL before an operation and only intraoperatively determine further values, such as the refractive power of the lens, and, if necessary, correct the selection on the basis of these values.

[0028] In a further advantageous embodiment, a first measuring device is suitable and intended to determine the first measured value in an aphakic eye. The method described here generally has the advantage that errors in a patient-specific eye model can be corrected. For example, it is generally not easy to determine the topography of the posterior surface of the cornea, which borders the aqueous humor.

[0029] Since the device and method described above preferably compare the actually measured refraction of an aphakic eye model with the aphakic patient-specific eye model, the influence of inaccurate measurements, such as the topography of the posterior cornea, can be eliminated. In other words, it is proposed to compare measurement results from aphakic eyes and eye models with each other. In this way, a suitable IOL can be reliably selected for a patient's eye, even in difficult cases. Such cases may, for example, involve eyes that have already been surgically treated, such as eyes treated with LASIK. In this case, the patient's cornea has been modified, making preoperative IOL selection very difficult. With the procedures and methods described here and below,However, these corneal modifications can be taken into account with devices.

[0030] According to the invention, the device has a second computing unit that is suitable and intended to determine at least one second output value that is characteristic of a postoperative visual impairment (or refraction) of the eye using at least the value determined or specified intraoperatively and the value determined or specified preoperatively (or likewise intraoperatively). In this embodiment, it is proposed that the computing unit predicts a visual impairment of the eye, in particular on the basis of a computer model using the values ​​determined by measurement or measured values ​​provided otherwise. This second computing unit can, for example, contain a computer module for predicting a postoperative refraction of the eye. In particular, the values ​​mentioned are measured values ​​or measured values.

[0031] This computer module, in turn, can have a transfer means or an interface for transferring model data for describing a patient-specific eye model, as well as a computing unit suitable for radiation analysis, e.g., optics software such as Code-V or Zemax. The data provided to the computing unit or the model data can include preoperative and / or intraoperative measurements. In addition, values ​​based on these values ​​can also be used, for example, values ​​calculated from preoperative and / or intraoperative data.

[0032] In addition, synthetic model data can also be used, which are or were obtained computationally from preoperative and intraoperative data.

[0033] These values ​​can, for example, be a tuple of numbers that describes a postoperative geometry of the cornea of ​​the patient's eye, which was preferably also obtained by means of computational simulation based on a preoperatively determined cornea geometry and intraoperatively performed incisions.

[0034] This model data from a patient-specific eye model advantageously describes the corresponding condition of the patient's eye, and the calculated parameters describe the refraction of the eye. Depending on the model data used, the refraction of a phakic, aphakic, or pseudophakic eye can be determined using the corresponding parameters. Furthermore, boundary conditions such as intraocular pressure (IOP) or corneal deformation due to the eyelid speculum can preferably also be taken into account.

[0035] The parameters can be used to select a suitable IOL so that the refraction of the patient's eye in the postoperative state preferably comes close to the postoperative target refraction.

[0036] Preferably, the computing unit calculates the above-mentioned values ​​based on an eye model. Both preoperatively determined (i.e., determined) values ​​and intraoperatively determined (i.e., determined) values ​​of the eye can be used as parameters of this eye model. Based on these values, a postoperative refractive error of the eye can be predicted. This prediction can be performed during the procedure, i.e., intraoperatively, so that appropriate adjustments can be made, preferably depending on the determined postoperative refractive error.

[0037] The values ​​used by the computing unit or in a corresponding method, which represent properties of the eye or are characteristic thereof, and parameters of the eye model, which represent properties of the eye model, can be scalar values ​​or tuples, which themselves have multiple scalar values. For example, the value representing the curvature of the cornea of ​​the eye can be a radius of a sphere that approximates the shape of the cornea of ​​the eye. This value can also be an inverse radius of this sphere. Furthermore, this value can be a tuple of two individual values, which represent curvatures along different planes of the cornea, particularly in connection with astigmatic refractive errors of the eye.Furthermore, the value representing the curvature of the cornea can be a tuple with, for example, several Zernike coefficients, which represent an aspheric shape of the cornea up to a given order in a manner known per se.

[0038] The value representing the distance between the corneal vertex and the crystalline lens can, for example, be measured directly preoperatively. However, other methods are also possible. For example, it would be possible to measure the distance between the corneal vertex and the retina, and then subtract the measured value of the distance between the crystalline lens and the retina from this measured value.

[0039] In this way, the tuple of the distance between the corneal vertex of the eye and the retina (and possibly also the tuple of the distance between the crystalline lens and the retina) is a value that represents the distance between the corneal vertex of the eye and the crystalline lens. Furthermore, the value representing the distance between the corneal vertex of the eye and the crystalline lens can be related to the principal plane of the crystalline lens, the vertex of the anterior lens surface, the vertex of the posterior lens surface, or another physically present or mathematically conceived element of the lens. Thus, one of these values ​​can be determined that is characteristic of the relevant distance.

[0040] In a further advantageous embodiment, the second computing unit determines the output value based on a model of the eye. This means that a computing model as described above is used, which preferably has or contains a plurality of parameters. These can be both preoperative and intraoperative measured values; in any case, they are preferably patient-specific measured values. In a further advantageous embodiment, this second computing unit is configured such that it determines the second output value taking into account the physical properties of a preselected IOL.

[0041] This model preferably includes multiple parameters. Furthermore, the model is based primarily on preoperative and intraoperative measurements. Furthermore, it is preferably a patient-specific model.

[0042] For example, it would be possible for a specific IOL to be selected in advance, but not yet inserted during the operation. Based on the physical (and / or optical) properties of this IOL as well as the measured values, a corresponding resulting refractive error (or a characteristic value for it) is then calculated. If this refractive error is very close to the desired or target refractive error, the preselected lens can actually be inserted. However, if the refractive error determined in this way deviates more than desired from the target visual acuity or refractive error to be achieved, a new calculation can be made, and the result can be used to determine how the IOL should be modified.

[0043] In a further embodiment, it is possible to measure the posterior aspect of the capsular bag while the eye is aphakic, and from this, the effective lens position (ELP) is determined, which describes the position of the implanted IOL in the patient's eye (or a future position of an IOL to be implanted). The ELP determined in this way thus belongs to the group of intraoperative model data. In addition, the eye length AL and corneal topography can also be used as preoperative model data.

[0044] Furthermore, data from a previously selected IOL, such as its refractive index, topography, thickness, and haptics, are preferably used as preoperative model data. If only the refractive power of a preoperatively selected IOL is known, it is possible to select the refractive index, topography, and thickness to approximately describe the effect of this IOL. For the sake of simplicity, the following presentation assumes that the patient's eye is rotationally symmetric and that a perfectly fitting rotationally symmetric IOL is to be selected.

[0045] First, the computer unit provides an intraoperatively created eye model that describes the postoperative patient eye. Table 1 below shows model data for such a model. This eye model is preferably created at a time when the patient's eye is aphakic and an IOL has not yet been implanted. The model data includes the curvature of the retina, the thickness of the vitreous body following the retina, and a corresponding refractive index.

[0046] Furthermore, data for the capsular bag are provided, as are its curvature and thickness. Furthermore, data for the IOL are provided, i.e., the IOL first inserted into the intraoperatively created eye model for approximation purposes.

[0047] Finally, the corresponding corneal data are provided. The aforementioned ELP is incorporated into the aqueous humor thickness data, which are included in rows 3 and 5 of Table 1. Based on this data, a result can now be output that describes whether a lens was correctly selected. Furthermore, it would also be possible to represent a lens section of an eye or an eye model with an IOL according to the data used in the intraoperative eye model. This is explained further below with reference to the figures.

[0048] Therefore, the second computing unit preferably determines the second output value based on a model of the eye. The second computing unit preferably determines the second output value taking into account the physical properties of a preselected IOL. This means that these physical data or parameters of a preselected IOL, which are used, for example, for a first approximation, are incorporated into the model or are taken into account by the second computing unit.

[0049] In a further advantageous embodiment, the device comprises a comparison device that compares the second output value with another value or target value. This target value can be, for example, a desired target refraction or a desired target refractive error of the eye. The comparison device compares the computationally determined output value (which, in particular, also represents a refraction) with this target value, and based on this comparison, it can be determined whether the originally selected lens is suitable for the operation.

[0050] If, for example, the determined output values ​​lie within a certain range or limit compared to the target value (for example, a difference between these values ​​or a ratio can be calculated here), the originally selected lens can be considered suitable and used accordingly. If there are deviations beyond this, these deviations can be used to determine which direction modifications need to be made, for example whether a lens with a higher or lower refractive power should be used. It would be possible to retain different values ​​for this additional lens and, for example, only adjust one refractive power. These steps can be performed several times, in particular until a suitable IOL has been selected.

[0051] In a further advantageous embodiment, the first or second computing unit determines the characteristic value using a beam path prediction device. For example, the computing unit that determines the postoperative refraction, as mentioned above, can use a beam path prediction device, such as a ray tracing method. Suitable software such as Code V or Zemax can be used for this purpose. Using ray tracing, it is possible to calculate the aberrations of the eye model intraoperatively and in particular before the implantation of an IOL and, for example, to predict parameters such as a sphere, an axis, and a cylinder. In addition, other parameters such as Zernike coefficients of the eye model could also be determined.

[0052] In general, the model of the eye can be realized in a variety of ways. For example, the model of the eye can be simulated on a computer using optics software. Examples of such optics software are, as mentioned above, Code V or Zemax. Typically, such software is supplied with parameter sets in a suitable format that define the optical properties of the simulated object, i.e., the eye.

[0053] These parameters include, in particular, parameters representing the distances between interfaces, the refractive indices of the media between the interfaces, and the curvatures of the interfaces. Numerous such models have already been developed for the human eye, such as the Gullstrand eye model.

[0054] In such an eye model, the shape of the cornea can also be calculated, using a finite element model. This calculation can be performed before it is incorporated into the eye model, or the calculation of the shape of the cornea can be an intrinsic component of the eye model. The preferred use of such finite element models allows for the inclusion of incisions in the cornea, which are used to insert surgical instruments into the eye, insert the intraocular lens, or correct refractive errors.

[0055] Thus, both preoperatively determined (i.e., ascertained) values ​​and intraoperatively determined (i.e., ascertained) values ​​are preferably assigned to the parameters of the eye model in order to determine the postoperative refractive error of the eye by performing calculations on the eye model. In a preferred embodiment, the intraoperatively determined (i.e., ascertained) values ​​of the eye also include a value that can be obtained by a wavefront measurement on the eye. On the basis of such a value, it is possible to directly draw conclusions about the refractive error of the eye during the operation, or this value can be used to check the consistency of an eye model that has already been used. If necessary, it would also be conceivable to change certain parameters of the model depending on values, such as the values ​​determined by the wavefront measurement. The wavefront measurement is preferably carried out before the intraocular lens is inserted.

[0056] However, it would also be possible to perform additional calculations after the IOL has been inserted.

[0057] When inserting an intraocular lens with astigmatic power, it is particularly advantageous if intraoperatively determined (ie determined) values ​​of the eye also include values ​​obtained by a wavefront measurement on the eye, since from such a value it can be concluded whether the orientation of the inserted intraocular lens should be changed or not.

[0058] The actual insertion of the intraocular lens involves further procedural steps, such as attaching a lid clamp to the eye, particularly before inserting the intraocular lens into the eye, and removing this lid clamp, particularly after correcting the position or orientation of the inserted intraocular lens. The lid clamp is attached to the eye to keep it open during the procedure. However, this lid clamp exerts a certain amount of pressure on the cornea, which can cause it to become deformed by the pressure of the lid clamp. A cornea deformed in this way can lead to wavefront measurements on the eye revealing a suspected refractive error, which can lead to unnecessary changes in the planning of the procedure.

[0059] In a preferred approach, such problems resulting from corneal deformation by the eyelid clamp can be avoided by using a preoperatively determined or measured value of the corneal curvature as a parameter to determine the postoperative refractive error of the eye model used.

[0060] In a further advantageous embodiment, the first measuring device is a measuring device selected from a group of measuring devices, including devices for refraction measurement, keratometers for topography measurement, devices for measuring the position of incisions, devices for (particularly contactless) measurement of intraocular pressure (IOP), devices for measuring layer boundaries (e.g., an OCT), an analog or digital ophthalmic surgical microscope, a device for measuring distances between eye structures, combinations thereof, and the like. Advantageously, the first measuring device can also comprise several of these measuring devices.

[0061] In a further advantageous embodiment, a measuring device which determines a value characterising the curvature of the cornea of ​​the eye is a keratoscope or an OCT measuring device.

[0062] In a further advantageous embodiment, the measuring device for determining the value representing the distance between the corneal vertex of the eye and the retina of the eye is an OCT measuring device, an ultrasound measuring device or a layer boundary measuring device.

[0063] In a further advantageous embodiment, a measuring device which determines a value representing the distance between the corneal vertex of the eye and the eye lens and / or a device which determines a value representing the distance between the corneal vertex of the eye and an intraocular lens is an OCT measuring device or a layer boundary measuring device.

[0064] In a further advantageous embodiment, the measuring device which measures a value representing a centration of the intraocular lens in the eye is a wavefront measuring device or an ametropia measuring device.

[0065] In a further advantageous embodiment, the model of the eye takes into account at least one parameter representing a position and, in particular, an orientation and / or length of at least one incision in the cornea of ​​the eye. Such an incision can be made, in particular, before the insertion of the IOL.

[0066] Preferably, the model also considers a parameter representing the position and in particular the orientation and / or length of the at least one incision in the cornea of ​​the eye. This parameter can be assigned a value that is determined based on the at least one incision made in the cornea of ​​the eye.

[0067] In a further advantageous embodiment, the above-mentioned output value is characteristic of a refractive power of the intraocular lens to be selected. As mentioned above, it is possible to retain other data or parameters of the intraocular lens to be selected and adjust only a refractive power. For example, the computing device can be configured to determine the value representing the intraocular lens using the Haigis formula, the Hoffer formula, the Holladay formula, the SRK / T formula, or another calculation method.

[0068] The value that characterizes the intraocular lens can be, for example, the refractive index or a material designation of the material used for the lens. It can also be a radius of curvature of one or both surfaces of the intraocular lens, or it can be a designation for a type of intraocular lens to be used, under which the intraocular lens in question is marketed.

[0069] The present invention is further directed to a selection method for selecting lenses, and in particular intraocular lenses. At least one first value is provided that is characteristic of an eye to be surgically treated. Furthermore, at least one second value is provided that is characteristic of an aphakic eye to be fitted with an intraocular lens to be selected. Furthermore, at least the first value and the second value and / or values ​​derived therefrom are input into a computing unit, and at least one output value is determined that is characteristic of an intraocular lens to be selected. The values ​​can be measured values, but it would also be conceivable to use calculated values.

[0070] Preferably, the first value and the second value are values ​​that are characteristic of the same patient, and in particular, of the same eye of the same patient. It should be noted that for the present method, it is irrelevant how the respective (measured) values ​​are obtained, for example, by measurement, simulation, or the like. Nor is it necessarily required that these values ​​be obtained by a treating physician. It is also crucial for the method according to the invention that the IOL is selected based on these values.

[0071] In a preferred embodiment, at least one output value is determined based on the first value and the second value, which is characteristic of a visual impairment of an eye equipped with a given lens. Preferably, at least one value, and in particular the first value, is a value that describes an aphakic eye.

[0072] In a further advantageous embodiment, the output value is compared with a value characteristic of a preselected IOL. Preferably, based on this comparison, a decision is made as to whether the preselected IOL can be definitively used, particularly for an ongoing or future operation.

[0073] In a further preferred embodiment, the currently available types of IOLs of the eye surgery device can be known and stored, for example, in a database to which the control device and / or the first computing device has access.

[0074] It is possible that measurements may be taken on the eye before the procedure using the second measuring device to determine preoperative values. These preoperative values ​​represent the properties of the eye before the procedure.

[0075] Furthermore, measurements can preferably generate a plurality of values. These values ​​can, in particular, be a value representing the curvature of the cornea, a value representing the distance between the corneal vertex and the lens of the eye, and a value representing the distance between the corneal vertex and the retina of the eye.

[0076] Further advantages and embodiments can be seen from the attached figures:

[0077] Showing: Fig. 1 is a schematic representation of an eye surgery device according to the present invention; Fig. 2 a representation of a calculated eye model; Fig. 3 a representation of a modified calculated eye model; Fig. 4 shows a sequence or procedure for determining an IOL according to a first embodiment; Fig. 5 shows a representation of a corresponding process or procedure for determining an IOL according to a further embodiment.

[0078] Fig.1 shows a schematic representation of an eye surgery device 1 according to the invention. With the aid of this eye surgery device 1, a further method explained in the figures for inserting an intraocular lens into an eye can be carried out. For this purpose, the eye surgery device 1 has a control device 3 and a user interface 5. This user interface 5 can communicate with the control device 3 and / or exchange signals or data with it. Furthermore, the device has a first measuring device 9 for determining intraoperative values ​​W1 (or values ​​to be determined intraoperatively) of an eye, and a second measuring device 7 for determining preoperative and / or intraoperative values ​​W2 (i.e. values ​​to be determined preoperatively and / or intraoperatively) of an eye.In addition, a first computing unit 11 is provided for selecting an intraocular lens, and a second computing unit 13 is provided for determining a postoperative refractive error. Reference numeral 16 denotes a display device for displaying values, such as an output value characteristic of an IOL to be selected.

[0079] It would be possible that the Fig.The device shown in Figure 1 is constructed as a distributed system, in which, for example, the first measuring device and the second measuring device are separate devices that are provided at different locations and / or used at different times and possibly by different operators, in particular to perform measurements on a patient's eye. The measured values ​​W1 acquired by the first measuring device 9 and the measured values ​​W2 acquired by the second measuring device 7 are transmitted as measured data to the control device 3. The control device 3 forwards the measured values ​​or data or values ​​derived therefrom to the two computing units 11, 13.

[0080] Advantageously, the control device 3 has a memory device 32 that is suitable and intended for storing these measured values ​​or data derived from these measured values. However, this memory device 32 can also be present in the respective measuring devices, or an additional memory device can also be present. The control device 3 can also, as in Fig. 1 schematically shown, be designed as a distributed system and be at least partially integrated into the individual measuring devices 7 and 9.

[0081] The user interface 5 can, for example, have a display device such as a screen 16 suitable for displaying and outputting data. In addition, the user interface 5 can have an input device, such as a keyboard or a mouse, via which the user can enter data. Furthermore, it is also possible for the user interface 5 to be constructed as a distributed system. Thus, part of the functionality can be integrated into the respective measuring devices 7 and 9 and / or further parts can also be integrated into other system components not shown. In particular, the screen 16 can also be a microdisplay whose image information can be projected into the eyepieces of an optical observation system.

[0082] Reference numeral 11 denotes a first computing unit, which is intended for determining an intraocular lens to be selected. This first computing unit is preferably realized as a software module implemented in one or more computers. However, additional software can also be provided in these computers, which provides functions of the control device 3, the user interface 5, and the two measuring devices 7, 9. This first computing unit 11 can determine a first output value A1 and / or output it to the control device 3, which is characteristic of an IOL to be selected. This is preferably a value that uniquely characterizes this IOL, such as an identification number or certain physical properties that are characteristic of this IOL.This first output value A1 can also be output by the control device 3 to the user interface 5 and also displayed by the display device 16.

[0083] The second computing unit 13 can also be implemented as a software module. This second computing unit 13 takes into account at least the measured values ​​of the first measuring device 9 and the second measuring device 7. However, it would also be possible, under certain circumstances, for measurements to be taken only on an aphakic eye, and for all relevant data to be obtained from these measured values. The second computing unit 13 can output a second output value A2, which is characteristic of the refractive error of the eye.

[0084] This second output value A2 can also be transmitted to the control device 3 and also output (in particular by the control device 3) to the user interface 5 and / or displayed by the display device 16.

[0085] Reference numeral 34 denotes a comparison device that compares the output value A2 output by the second computing unit 13, which is characteristic of a refractive error of the eye using the preselected IOL, with a target value S or a target refraction. This target value S can preferably be entered via the user interface 5.

[0086] Reference numeral 36 denotes a calculation unit that outputs a value V that is characteristic of this comparison, such as a difference or a ratio of the compared values. Reference numeral 42 denotes a beam path prediction device, such as a ray tracing module.

[0087] The Fig. 2 and Fig.3 serve to explain a device and a method according to the invention. As already mentioned above, one object of the invention is to provide a device and a method with which a correct lens can be selected intraoperatively. According to a Fig. 3 and Fig. In the example illustrated in Figure 4, a patient's eye is chosen for which a postoperative target refraction of -1 diopter of myopia was agreed upon, so that the patient has optimal visual comfort at a distance of 1 meter without glasses. For this patient, a biconvex symmetric IOL with a curvature of ρ = 1 / 12.1 mm = 0.082645 / mm, a thickness of 1.3 mm, and a refractive index of 1.464 was selected preoperatively in a preliminary examination.

[0088] In the aphakic state, a measurement of the back of the capsular bag is taken and, together with other data, the effective lens position (ELP) is determined. Fig. Figure 3 shows a lens section generated using the data set contained in Table 1. Reference numeral 12 refers to the cornea, reference numeral 10 to the IOL, and reference numeral 14 to the capsular bag. Aqueous humor is located between the lens 10 and the cornea, and also between the IOL and the capsular bag 14. Reference numeral 6 denotes the vitreous body of the eye, and reference numeral 18 denotes the retina. This data set of the above-mentioned data can be transferred to a computer module for predicting postoperative refraction, so that parameters for evaluating the refractive error of the eye model can be determined, which simultaneously represents a prognosis of the refractive error of the postoperative eye if the corresponding IOL were implanted.

[0089] The following Table 1 shows the data set describing the eye model in this embodiment. Table 1: Dataset describing the eye model shown in Fig. 3 with preselected IOL Curvature ρ [1 / mm]] Thickness [mm] Refractive index n (λ = 550nm) 1 (Retina) +0,086207 17,72 1,336 2 (capsule bag - back) +0,170648 0,1 1,386 3 (Capsule bag - front) +0,173611 1,115 1,336 4 (IOL - back) +0,082645 1,3 1,464 5 (IOL front) -0,082645 3,65 1,336 6 (cornea back) -0,147059 0,5 1,376 7 (Cornea - front) -0,129870

[0090] If the predicted refractive error is generally close enough to the postoperative target refraction or the target value (for example, if the difference between the predicted refractive error and the postoperative target refraction is less than 1 diopter, preferably less than 0.4 diopter, and particularly preferably less than 0.2 diopter), then the intraoperatively selected IOL is identical to the preoperatively selected IOL, and the intraoperative IOL selection process is complete. In this case, the preoperatively selected IOL, which does not differ or differs only slightly from the determined IOL, can be used.

[0091] If the magnitude of this difference is too large compared to the desired postoperative target refraction, a more suitable IOL type with different parameters is selected. The sign of this difference can be used to determine whether an IOL with a higher or lower refractive index is selected for the next iteration. Subsequently, the model data from Table 1 are modified according to the newly selected IOL to describe the newly selected IOL and its position in the patient's eye.

[0092] The corresponding refractive error parameters are then determined from the model data, as well as the difference between the predicted refractive error and the postoperative target refraction. In the next step, a decision is made as to whether the magnitude of this difference is sufficiently small or whether another iteration is necessary.

[0093] In the presentation of Fig.2 and the data set shown in Table 1 would result in the depicted rays converging approximately 40 cm (to the right) from the cornea, thus resulting in optimal vision in this range. As mentioned above, however, optimal vision should be within 1 meter. In other words, in the case of the model data from Table 1, the preoperatively selected IOL would result in a myopic refractive error of -2.46 diopters. The predicted refractive error of 2.46 diopters for the postoperative eye thus deviates by 1.46 from the postoperative target refraction of -1 diopter, meaning that the postoperative target refraction is better achieved when an IOL with a lower refractive power is implanted.

[0094] Through the interaction of the computing units 11 and 13 of the device according to the invention, the IOL is now selected from the available IOLs for which the corresponding patient-specific eye model provides a value as a parameter for the refractive error that is sufficiently close to the desired postoperative target refraction. In this exemplary embodiment, this intraoperatively selected IOL is described by the following specifications: biconvex, curvature ρ = 1 / 13.3 mm = 0.075188 mm, thickness 1.1 mm, and refractive power n = 1.464.

[0095] The following Table 2 shows the corresponding model data. Table 2: Dataset describing the eye model with second IOL shown in Fig. 3 Curvature ρ [1 / mm]] Thickness [mm] Refractive index n (λ = 550nm) 1 (Retina) +0,086207 17,72 1,336 2 (capsule bag - back) +0,170648 0,1 1,386 3 (Capsule bag - front) +0,173611 1,215 1,336 4 (IOL - back) +0,075188 1,1 1,464 5(IOL front) -0,075199 3,75 1,336 6 (cornea back) -0,147059 0,5 1,376 7 (Cornea - front) -0,129870

[0096] Fig.Figure 3 shows a corresponding cross-sectional image. The parameter for the refractive error is calculated to be -1.11 diopters, resulting in only a small deviation from the postoperative target refraction of -1 diopter. The user or surgeon is then informed via user interface 5 that using this IOL will achieve the desired postoperative target refraction for the patient. In the figure from Fig. 4, the rays would converge to the right at a distance of approximately one meter from the cornea, which would correspond to the desired specifications. It can be seen that the selected Fig. 3 and Fig. 4 IOLs shown differ from each other.

[0097] Fig.Figure 4 shows a method that can be carried out using a device according to the invention according to a first variant. Accordingly, preoperative and intraoperative measured values ​​are initially provided. These can be determined through measurements, but other methods for obtaining this data are also conceivable. This data can also be predetermined by a physician, but it would also be possible for it to be determined solely through the use of devices or machines, thus eliminating the need for a physician's involvement.

[0098] In the first variant of the procedure, preoperative measurement values ​​W2 and intraoperative measurement values ​​W1, as well as data L from a lens that has not yet been inserted, are provided in a process step I. This data represents the initial data used for a calculation. However, data could also be imported, for example, from a transparent film.

[0099] In process step II, the expected refractive error of the eye is determined using the measured values ​​W1 and W2 and the data L. The measured values ​​are, for example, the preoperative values, such as the curvature of the cornea or the distance from the corneal vertex to the retina. The now determined refractive error is compared with a desired target refractive error (process step III). In a further process step IV, a deviation between the determined refractive error and the target refractive error is determined, and it is checked whether this deviation is acceptable.

[0100] For example, if only a deviation of 0.2 diopters or less occurs, it could be determined that this deviation is acceptable. In this case, the preselected IOL can be used. If the deviation between the determined refractive error and the target refractive error (step IV) is unacceptable, a new IOL with modified L data can be determined based on the deviation.

[0101] The modified data L of this IOL are again used, as indicated by the arrow P1, in process step II to determine the refractive error (instead of the initial data for the preselected IOL) in a further sequence of process steps II and III. According to process step IV, the query is again made as to whether the deviation between the determined refractive error and the target refractive error is acceptable. These process steps I to IV are repeated until the deviation is finally acceptable and the lens now determined can be used for the operation. The process shown here is therefore based on an iteration of a computational test to determine whether a preselected IOL is suitable for use. It should be noted that no measurements need to be taken on the patient's eye for these steps.While the above-mentioned values ​​W1 and W2 are determined in particular by measurements, no further measurements are preferably carried out within the scope of the steps or iterations described here, but approximations to a desired result, such as a desired refraction, are made in a predetermined number of steps.

[0102] At Fig.4, it was assumed that the lenses used were rotationally symmetrical. If the preoperative corneal geometry deviates from rotational symmetry, a toric IOL can also be fabricated preoperatively. In this case, as an additional step, the coordinate system used is oriented so that the Z-axis corresponds to the optical axis of the eye and that the principal curvatures of the cornea in the XZ plane and the YZ plane are recorded. In this case, the model data can also be described similarly to the tables mentioned above. However, the curvatures in the X and Y directions also differ from each other. In this case, it is also advantageous to consider the correct orientation of the IOL in the patient's eye in the model data, which in turn forms the basis for the calculation using the parameter. In these cases, it would be possible to supplement the above-mentioned table with model data.

[0103] It would also be possible to use synthetic, i.e., non-directly measured, model data. For example, the corneal topography of the eye model could be the topography obtained by taking into account the deformation of the corneal topography caused by the incisions. It is also possible for these incisions to be deliberately placed to reduce deviations of the corneal topography from rotational symmetry. This procedure is referred to as a limbal relaxing incision (LRI).

[0104] In addition, it would also be possible to use synthetic model data that predict the corneal topography of the eye model after healing, especially in the postoperative state.

[0105] Fig.Finally, Figure 5 shows a further sequence of a method using the device according to the invention. In this method, preoperative values ​​W2 are provided (method step I). The example now shown describes a method by which the patient's postoperative refraction is closer to the postoperative target refraction.

[0106] The preoperative data can be a corneal topography, an eye length, a corneal thickness, etc. This allows for a preoperative IOL selection, for which a patient-specific eye model can be used, as described above with reference to Fig. 1 (method step II). However, the expected aphakic refraction of the eye is now determined using these (measured) values. In other words, the aphakic refraction is predicted using an aphakic, patient-specific eye model.

[0107] In a further procedural step, intraoperative (measured) values ​​W1 are provided, which describe an aphakic eye (procedural step III). An intraoperative aphakic refraction measurement can be performed. In this case, disruptive effects, such as pressure from the eyelid clamp on the cornea or the influence of intraocular pressure, can be preferentially corrected.

[0108] Similar to the previously described variant, a deviation between the determined aphakic refractive error in the aforementioned steps II and III is determined, and it is determined whether these deviations are acceptable. If the deviations are acceptable, the selected IOL can be used. If the results are unacceptable, a new IOL can be determined based on the deviation, with its refractive power differing from the preselected IOL according to the theoretical deviations from process step IV. Preferably, a new IOL is selected, with particularly preferably only one refractive index being varied.

[0109] It should be noted again that no lens is used in this process yet. Only after a certain number of iterations has been completed can the lens be used or inserted.

[0110] The applicant reserves the right to claim all features disclosed in the application documents as essential to the invention, provided that they are new, individually or in combination, compared to the prior art. List of reference symbols 1 eye surgery device 3 Control device 5 User interface 6 vitreous body 7 second measuring device 9 first measuring device 10 Intraocular lens 11 first computing unit 12 Cornea 13 second computing unit 14 Capsular bag 16 Display device 18 Retina 32 storage device 34 Comparison device 36 Calculation unit W1, W2 (measured) values A1, A2 output values S Target value, target refraction V value for comparison L Data of a preselected but not yet implanted IOL

Claims

[1] Eye surgery device (1) with - a control device (3); - a user interface (5) which is at least temporarily in data communication with the control device (3); - a first measuring device (9) which is suitable and intended to determine intraoperatively at least one value (W1) which is characteristic of an eye to be surgically treated, - a second measuring device (7) which is suitable and intended to determine preoperatively and / or intraoperatively at least one value (W2) which is characteristic of the eye to be surgically treated, and with - a first computing unit (11) which is suitable and intended to determine at least one first output value (A1) which is characteristic of at least one intraocular lens (IOL) to be selected, using the intraoperatively determined value (W1) and the preoperatively and / or intraoperatively determined value (W2), wherein the user interface preferably has at least one output device (16) which is suitable for outputting the output value (A1) or a value derived therefrom; characterized by , that. the device (1) has a second computing unit (13) which is suitable and intended to determine at least one second output value (A2) which is characteristic of a postoperative visual impairment of the eye using the intraoperatively determined value (W1) and the preoperatively determined value (W2) on the basis of a model of the eye. [2] Eye surgery device (1) with - a control device (3); - a user interface (5) which is at least temporarily in data communication with the control device (3); - a first measuring device (9) which is suitable and intended to determine intraoperatively at least one value (W1) which is characteristic of an eye to be surgically treated, - a second measuring device (7) which is suitable and intended to determine preoperatively and / or intraoperatively at least one value (W2) which is characteristic of the eye to be surgically treated, and with - a first computing unit (11) which is suitable and intended to determine at least one first output value (A1) which is characteristic of at least one intraocular lens (IOL) to be selected, using the intraoperatively determined value (W1) and the preoperatively and / or intraoperatively determined value (W2), wherein the user interface preferably has at least one output device (16) which is suitable for outputting the output value (A1) or a value derived therefrom; characterized by , that. the device (1) has a second computing unit (13) which is suitable and intended to determine at least one second output value (A2) which is characteristic of a postoperative visual impairment of the eye using the intraoperatively determined value (W1) and the preoperatively determined value (W2), wherein the second computing unit (13) determines the second output value (A2) taking into account physical properties of a preselected IOL. [3] Eye surgery device (1) according to claim 1 or 2, characterized by that the first measuring device (9) is suitable and intended to determine the first value (W1) in an aphakic eye. [4] Eye surgery device (1) according to claim 2, characterized bythat the second computing unit (13) determines the second output value (A2) based on a model of the eye. [5] Eye surgery device (1) according to claim 1, characterized by that the second computing unit (13) determines the second output value (A2) taking into account physical properties of a preselected IOL. [6] Eye surgery device (1) according to at least one of the preceding claims 1-5, characterized by that the eye surgery device (1) has a comparison device (34) which compares the second output value (A2) with a target value. [7] Eye surgery device (1) according to at least one of the preceding claims, characterized by that the first computing unit (11) determines the value using a beam path prediction device (42). [8] Eye surgery device (1) according to at least one of the preceding claims, characterized bythat the first measuring device (9) and / or the second measuring device (7) has at least one measuring device which is selected from a group of measuring devices which includes devices for refraction measurement, keratometers for topography measurement, devices for measuring the position of incisions, devices for contactless measurement of an eye pressure, devices for measuring layer boundaries, an ophthalmological surgical microscope, combinations thereof or the like. [9] Eye surgery device (1) according to claim 1 characterized by that the model of the eye takes into account at least one parameter which represents a position and in particular an orientation and / or a length of at least one incision in the cornea of ​​the eye. [10] Eye surgery device (1) according to claim 1 characterized by that the model of the eye takes into account at least one parameter that represents a centration of the intraocular lens in the eye. [11] Eye surgery device (1) according to at least one of the preceding claims, characterized by that the output value (A1) is characteristic of a refractive power of the intraocular lens (IOL) to be selected. [12] Eye surgery device (1) according to at least one of the preceding claims, characterized by that the control device (3) is designed such that it waits for a predetermined input from the user into the user interface before at least one measuring device is caused to determine intraoperative and / or preoperative measured values. [13] Selection method for selecting lenses and in particular intraocular lenses comprising the steps: - providing at least one first value (W1) which is characteristic of an eye to be surgically treated; - providing at least one second value (W2) which is characteristic of an aphakic eye to be fitted with an intraocular lens to be selected, - Input of at least the first value (W1) and the second value (W2) into a computing unit and determination of at least one output value (A1) which is characteristic of an intraocular lens to be selected characterized by that on the basis of the first value (W1) and the second value (W2) and taking into account physical properties of a preselected IOL, at least one value is determined which is characteristic of a visual defect of an eye to be fitted with this preselected IOL. [14] Method according to claim 13, characterized by that on the basis of the first value (W1) and the second value (W2) at least one value is determined which is characteristic of a visual impairment of an eye equipped with a given lens.

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