WO2013004590A1

WO2013004590A1 - Corneal implant

Info

Publication number: WO2013004590A1
Application number: PCT/EP2012/062591
Authority: WO
Inventors: Gregor Stobrawa; Michael Bergt
Original assignee: Carl Zeiss Meditec Ag
Priority date: 2011-07-01
Filing date: 2012-06-28
Publication date: 2013-01-10
Also published as: DE102011106289A1; CN103687573A; CN108992205A

Abstract

The invention relates to a corneal implant, in particular for placing in a corneal pocket, and to a device for fitting such an implant in place. To this end, the corneal implant for correcting defective vision, in particular of higher order, has at least one marking which permits a clear orientation of the implant in the cornea and is designed such that the visual impression is not impaired. The device has an observation arrangement and at least one illumination system for illuminating and exciting at least one marking of the corneal implant arranged in an eye.

Description

Corneal implant

The invention relates to a corneal implant, in particular for placement in a corneal pocket, and to a device for placing such an implant.

It is known to have refractive errors of the eye, i. To treat refractive errors by means of laser, in order to make the use of glasses superfluous.

In this case, on the one hand corneal material can be purposefully vaporized and thus removed by means of an excimer laser, and so the refractive effect of the cornea can be changed so that the defective vision is compensated.

Another method is based on using a femtosecond laser to separate a substantially lense-shaped piece of tissue within the cornea and by a

To remove opening cut. This method is known by the name FLEx (Femtosecond Lenticule Extraction). The dimensions of this tissue piece are chosen so that after removal of the separated piece of tissue, the resulting corneal shape also corrects the refractive error. In this case, asymmetric errors (coma, astigmatism, etc.) can be compensated by suitable control of the laser, which are also referred to as higher-order errors. The removed corneal material is generally destroyed.

Since the cornea has only a small thickness (about 400-650 μιη), not all

Trouble shooting due to removal of material remedy, in particular concerns the

Myopia (myopia). Therefore, it is also known to introduce into the cornea material in the form of intrastromal corneal rings or ring segments (ICR - Intracorneal Ring, ICRS - Intracorneal Ring Segment). These consist of one

biocompatible plastic and are used in z. B. produced by femtosecond laser "pockets" in the cornea (see US 6 875 232) .These, however, can only correct low-vision disorders.

There is therefore a need to be able to use corneal implants for the correction of refractive errors of higher order. For this purpose, US Pat. No. 7,776,086, the entire contents of which are hereby incorporated by reference, proposes using an aspherical lens as an implant. However, this solution remains limited to the correction of radially symmetrical errors of the eye.

In US 6,855,163, the entire contents of which are hereby incorporated, it is disclosed to place a plurality of implants at different locations in the cornea. Even if the inventor does not do so, this could also be a non-symmetrical one Ametropia are treated. However, this solution is very complicated by the need for multiple pockets in the cornea and the exact placement of the various implants.

EP 1 871 298 discloses a method for the treatment of presbyopia by introducing corneal inlays into the cornea which have the effect of a diaphragm, in addition means for detecting the depth of insertion are provided.

The invention is therefore based on the object to overcome the disadvantages of the prior art and to provide a corneal implant can be treated with the non-radially symmetric error higher order.

It is a further object of the present invention to provide a device for placing such a corneal implant, which ensures a reliable and reliable detection of the position and position of the ophthalmological implant.

These objects are achieved by a cornea implant and a device for placement of such an implant according to the independent claims.

Advantageous embodiments of the invention are specified in the respective subclaims.

According to the invention, the cornea implant has at least one marking, by means of which a clear orientation of the implant in the cornea is possible, for the correction of defective vision, in particular of a higher order.

Advantageously, the marking is designed so that the visual impression is not disturbed.

For this purpose, it may be designed such that it can only be recognized outside the visible light spectrum for the human eye, which lies between approximately 380 nm and 780 nm or a partial region of the visual spectral range between approximately 450 nm and 750 nm. This makes it possible to attach permanent markings on the implant, which on the one hand do not affect the light transmission of the implant in the visual spectral range and on the other fluoresce or absorb outside of the human visible light spectrum, so that with a corresponding illumination of the implant reliable and reliable detection of the Position and / or identification of the implant on the basis of the marking without influencing or impairing the visual perception of vision of the implant carrier is made possible. For identification, the

Marking have a corresponding coding, e.g. for right / left,

Patient number or similar In advantageous embodiments of the corneal implant according to the invention, a fluorescent dye from one of the structural classes may contain the cyanines,

Mercury, phthalocyanine, povidone, porphyrin, chlorophyll, triarylmethane, xanthene, oxazine, thiazine, safranine, heterocyclic pyrilium and thiapyrilium salts, perrylenes, terrylenes, quaterrylenes, quaterneles, azo dyes, metal complexes or quinones. But it is also possible that a UV absorber from one of the structural classes benzophenones, benzotriazoles, as a light-absorbing dye,

Salicylic acid esters, resorcinol monobenzonates, oxalic acid anilides, cinnamic acid ester derivatives, p-hydroxybenzoic acid esters and / or an IR absorber from one of these structural classes. Other fluorescent or absorbing dyes are also useful for preparing the labels.

Alternatively, the at least one mark can be temporary and disappear, in particular, solely by the passage of time or external influence. Then it could also be designed so that it is visible in the visible spectral range. For example, such a dye could be water-soluble and removed, for example, by the tear fluid. Alternatively, the mark can also be made, for example, with a "Removable Ink Skin Marker" from Viscot Medical LLC (www.viscot.com/PSRpMarkers.html).

Further alternatively, the mark may also be given by a special one, in general

asymmetric, shaping of the implant can be realized.

According to the invention, the corneal implant consists of a biocompatible artificial or natural material (for example, corneal material of a donor or even its own cornea). This corneal material has been advantageously obtained by means of a femtosecond laser.

The corneal implants according to the invention make it possible to reliably and reliably display their position and position, for example, during or after a surgical procedure by means of a suitable observation system.

The invention also includes a device for placing a corneal implant which has an arrangement for observation and at least one illumination system for illuminating and exciting at least one marking of the one placed in an eye

Has corneal implant.

It is advantageous if this device furthermore has at least one camera for recording the fluorescent light emitting outside of the visible light spectrum for the human being or absorbent marking and at least one evaluation unit or display unit for at least one image taken by the camera of the marking.

The observation system according to the invention enables a reliable and safe

Detection of the position and position and / or identification of the implant.

A preferred embodiment of the invention results when the evaluation unit at least one Kemp lungsy system for coupling the recorded images of the mark in the

Arrangement for observation has.

It is advantageous if the illumination system comprises at least one light source, wherein the light source emits white light or an excitation light for the dye of the marker in a predetermined wavelength range.

An optical detection method according to the invention for detecting the position and position and / or the identification of an implant as described above comprises the following steps: a) Illumination of the implant with at least one light source of an illumination system, wherein the light source is white light or an excitation light for a dye Radiates marking of the implant in a predetermined wavelength range; b) recording by means of a camera the fluorescent or absorbing mark emitting outside the human visible spectrum of light; c) evaluation of at least one image of the mark taken by the camera by means of at least one evaluation unit. The detection method according to the invention ensures reliable and reliable detection of the position and position and / or identification of the implant. In addition, it is ensured that the application of the method does not impair the visual vision of an implant carrier, since the mark irradiated by white light or an excitation light in a predetermined waveband emits or absorbs outside of the human visible light spectrum.

A preferred embodiment of the invention will be explained below with reference to the schematic drawings.

Show it:

Fig. 1 is a section through the cornea

Fig. 2 is a plan view of the cornea with correctly inserted implant according to the invention

Fig. 3 shows a first variant of the introduction of the implant according to the invention

Fig. 4 shows a second variant of the introduction of the implant according to the invention Fig. 5 is a plan view of the cornea with incorrectly inserted implant according to the invention

6 shows a second embodiment of the implant according to the invention

Fig. 7 shows a third embodiment of the implant according to the invention

Fig. 8 shows an embodiment of the device for placing a corneal implant according to the invention.

1 schematically shows a cross-section of a cornea 1. This has a pocket 2 produced with a femtosecond laser, in which an implant 3 has been placed by inserting the implant 3 into the pocket 2 through the access 4. A method of creating the pocket 2 in the cornea 1 by means of a femtosecond laser is

for example, in DE 10 2006 053120, the entire contents of which are hereby incorporated by reference. With the same method, the implant 3 can be obtained from the cornea of a donor eye. In this case, the implant 3 has precisely such a shape that the refractive power of the cornea 1 locally changed by the introduction of the implant 3 into the cornea 1 corrects the imaging properties of the eye in the desired manner, wherein the implant 3 has a thin (smaller 200μιη) in the Generally has flexible structure, must be transparent and is adapted in its refractive index of the refractive index of the cornea 1, so that it is difficult to detect by conventional means. So that non-radially symmetric aberrations of the eye can be corrected, the implant must also have a shape deviating from the radial symmetry. Thus, the orientation of the implant in the pocket 2 becomes an important size, which must be strictly adhered to in order to correct the imaging properties of the eye. In order to be able to determine this orientation during the introduction of the implant into the cornea, the implant 3 has one or more markings 5, which permit an accurate insertion of the implant 3 through the access 4 (see FIG. 2). The implant 3 must be placed in the bag 2 so that the mark 5 at a

is located predetermined spot. To the implant 3 through the access 4, which

Usually smaller than the diameter of the implant 3, to insert into the pocket 2, it can be partially folded (FIG. 3) or folded (FIG. 4) and only after the

Insert unfolded or unfolded. In these cases, the markings 5 additionally make it possible to check whether the implant 3 has been unfolded or unfolded correctly. In this case, Figures 3 and 4 each still show the wrong state of incorporation of the implant, which is clearly visible in the wrong position of the mark 5. 5 shows by way of example the case that the placement of the implant did not take place correctly, the marker 5 is not in the correct position, the implant is twisted. Thus, the imaging properties of the eye are not corrected as desired, it can even lead to the generation of additional errors. The marker 5 is attached at the previous preparation or provision of the implant 3 at a defined location.

Fig. 6 shows a variant of the invention, in which the marking of the correct orientation by the shaping of the circumference of the implant 3 takes place, here as an elliptical shape.

FIG. 7 shows a further variant of the marking by shaping the circumference, here by a bulge 6 of the implant 3.

Fig. 8 shows a schematic representation of a device for placing a

Corneal implant as described in the embodiments of FIG. 2. The device 7 in this case comprises a microscope 8 with a microscope optics, a

Illumination system 9 for illuminating the marking 5 consisting of one or more dyes of the implant 3 arranged in the eye 10 via a partial beam path 17. Furthermore, the device 7 has a camera 11 for recording the fluorescent or absorbing markings 5 emitting outside the light spectrum visible to the human eye and at least one evaluation unit 12 for at least one image of the marking or markings 5 taken by the camera 11. In the illustrated embodiment, the markings 5 consist of a near-infrared fluorescent dye, for example, the dye indocyanine green. It is clear from FIG. 8 that the illumination system 9 radiates light of a specific wavelength and also white light via a beam splitter 13 to the eye 10 with the implant 3. The radiation emitted by the implant 3 or the markings 5 is in turn sent to the camera 11 via the beam splitter 13 and a second beam splitter 14 via a partial beam path 15. Via a further partial beam path 16, the image recorded by the eye 10 or the implant 3 is made available to the eye 18 of a viewer via the microscope 8 with the microscope optics. For this purpose, the beam splitter 13 as

partially transparent mirror formed. The images taken by the camera 11 are transmitted as image data via a data line 19 to the evaluation unit 12. The

Evaluation unit 12 has a coupling system 19 for coupling the recorded images of the marking 5 into the microscope optics of the microscope 8. The coupling system 19 in this case comprises a beam splitter or deflecting mirror 20 which is designed as a partially transmissive mirror and transmits the image taken by the camera 11 and evaluated by the evaluation unit 12 to the eye 18 of the observer. This makes it possible to get one Superimposed image consisting of the image taken by the camera 11

Mark 5 and the image of the object area, namely the observed implant 3 and its surroundings for a viewer to provide. Furthermore, the

Evaluation unit 12 an automatic tracking system for detecting movements and / or the position and position changes of the marking 5 and the implant 3 have. Furthermore, it is possible that the evaluation unit comprises an autofocus system, the focusing of the microscope optics on the implant 3 taking place by means of the images of the marking 5 taken by the camera 11 and their evaluation.

The illumination system 9 comprises a light source, wherein the light source is white light or an excitation light for the dye of the marker 5 in a predetermined

Wavelength range radiates. As light sources, for example, halogen lamps or laser light sources can be used. Furthermore, it is possible that the

Illumination system 9 is designed as a gap lighting system (not shown).

The device 7 as well as the implants 3 described in the embodiments according to FIGS. 2 to 7 can be used in surgical procedures which are intended to correct aberrations of the eye by inserting a corneal implant 3 into the cornea 1 of the patient. In particular, already during the insertion of the implant 3 into the cornea 1, a position and position control of the

Implant 3 made or make the surgeon appropriate corrections. As a result, a secure and accurate positioning of the implant 3 is ensured.

Claims

claims

1) corneal implant for the correction of ametropia, in particular higher order, characterized in that the implant has at least one mark.

2) corneal implant according to claim 1, characterized in that the at least one mark is designed so that the visual impression is not disturbed.

3) corneal implant according to claim 1 or 2, characterized in that the

at least one mark is recognizable in a light spectrum not visible to the human eye.

4) corneal implant according to claim 1, characterized in that the at least one marker is temporary.

5) corneal implant according to claim 4, characterized in that the at least one mark disappears by passage of time or external influence.

6) Corneal implant according to one of claims 1 to 5, characterized in that it consists of a biocompatible artificial or natural material.

7) Device for the placement of a corneal implant according to one of claims 1 to 6, characterized in that the device has an arrangement for observation and at least one illumination system for illumination and excitation of at least one mark of the corneal implant disposed in an eye.

8) Apparatus according to claim 7, characterized in that the illumination excites the marking for emission in the visible spectrum.

9) Device according to claim 7, characterized in that the device

at least one camera for recording the visible outside of the human visible spectrum of light mark and at least one

Evaluation unit or display unit for at least one of the camera

recorded image of the mark has.

10) Apparatus according to claim 8, characterized in that the evaluation unit or display unit at least one coupling system for coupling the

recorded images of the marker in the arrangement for observation.

11) Device according to one of claims 7 to 10, characterized in that the illumination system comprises at least one light source, wherein the light source emits white light or an excitation light for the dye of the marker in a predetermined wavelength range.