DE102020104687B4 - Method for controlling an eye surgical laser and treatment device - Google Patents

Abstract

Method for controlling an eye surgical laser (18) of a treatment device (10) for the separation of a volume body (12) with a predefined posterior interface (14) and a predefined anterior interface (16) from a human or animal cornea, comprising: - Controlling the Laser (18) by means of a control device (20) of the treatment device (10) in such a way that it emits pulsed laser pulses into the cornea in a shot sequence in a predefined pattern (42), the boundary surfaces (14, 16) of the solid body (12) to be separated are defined by the predefined pattern (42) and the interfaces (14, 16) are generated by means of an interaction of the individual laser pulses with the cornea by generating a large number of cavitation bubbles (40) generated by photodisruption, the cavitation bubbles (40) being generated by specifying a minimal absorbed dose (46) are generated in the cornea, the absorbed dose (46) indicating an average energy delivered by the laser beams to the cornea based on the mass of the irradiated cornea volume.

Description

The invention relates to a method for controlling an eye surgical laser of a treatment device for the separation of a solid body with a predefined posterior interface and a predefined anterior interface. The invention further relates to a treatment device, a computer program and a computer-readable medium.

Clouding and scarring within the cornea, which can result from inflammation, injury or congenital diseases, impair vision. Particularly in the event that these pathological and/or unnaturally changed areas of the cornea lie in the visual axis of the eye, clear vision is significantly impaired. Eye surgical lasers are also used to correct vision defects based on optical errors in the eye. Eye surgical lasers are used in particular in photorefractive keratectomy (PRK), laser epithelial keratomileusis (LASIK), epithelial laser in situ keratomileusis (Epi-LASIK) or transepithelial photorefractive keratectomy (Trans-PRK). For this purpose, different laser methods are available from the prior art using appropriate treatment devices, which can separate a solid body from the cornea and thus improve the vision for a patient. These laser procedures are an invasive procedure, so it is particularly advantageous for the patient if the procedure is carried out in the shortest possible time and to a particularly efficient extent.

The EP 2 958 531 A1 describes a method for adjusting the energy of pulsed, focused laser radiation. The method establishes a relationship between a threshold pulse energy required to cause irreversible damage in a material and a pulse duration. The relationship enables a threshold pulse energy to be obtained for each of a variety of pulse durations, including one or more pulse durations in a range between 200 fs and smaller. The relationship defines a decreasing threshold pulse energy for a decreasing pulse duration in the range between 200 fs and smaller. For a given pulse duration ranging between 200 fs and less, an associated threshold pulse energy is determined based on the established relationship. The pulse energy of the laser radiation is adjusted based on the determined associated threshold pulse energy. In certain embodiments, the relationship represents a decrease in threshold pulse energy substantially as a function of the cube root of the pulse duration.

The object of the present invention is to create a method for controlling an eye surgical laser, a treatment device, a computer program and a computer-readable medium by means of which efficient, safe and rapid treatment of an eye is ensured.

This object is achieved by a method for controlling an eye surgical laser, a treatment device, a computer program and a computer-readable medium according to the independent patent claims. Advantageous embodiments with useful developments of the invention are specified in the respective subclaims, with advantageous embodiments of the method being viewed as advantageous embodiments of the treatment device, the computer program and the computer-readable medium and vice versa.

A first aspect of the invention relates to a method for controlling an eye surgical laser of a treatment device for the separation of a solid body with a predefined posterior interface and a predefined anterior interface from a human or animal cornea. The laser is controlled by means of a control device of the treatment device in such a way that it emits pulsed laser pulses into the cornea in a shot sequence in a predefined pattern, the boundary surfaces of the solid body to be separated being defined by the predefined pattern and the boundary surfaces by means of an interaction of the individual laser pulses by means of the cornea by generating a large number of cavitation bubbles generated by photodisruption. The plurality of cavitation bubbles are generated, for example, along at least one cavitation bubble path of the predefined pattern, the cavitation bubbles being generated by specifying a minimum energy dose in the cornea.

This makes it possible for an eye to be treated efficiently, safely and quickly. In particular, the invention takes into account that with a minimum energy dose, a shortened recovery time for the patient after the treatment can be achieved. In other words, a patient who has been treated requires less recovery time in order to experience an increase in vision, for example.

The absorbed dose is the average energy delivered to the cornea by the laser beams gy based on the mass of the irradiated coronal volume. In particular, the invention takes into account that no cavitation bubble is formed below a predetermined energy. From a certain energy threshold, corresponding cavitation bubbles arise, with an increase in the respective energy also increasing the size of such a cavitation bubble. In order to use this effect, it can be provided that, for example, the pulse energy of the laser is selected such that at a predetermined distance between respective centers of adjacent cavitation bubbles, the so-called interbubble distance (interspot distance), that the two cavitation bubbles at least touch each other, in particular However, at least partially overlap so that no “bridges” are created between the individual cavitation bubbles with tissue that has not been removed. Alternatively, it can be provided, for example, that the intermediate bubble distance is selected or adjusted with constant energy in such a way that the cavitation bubbles overlap and form an overlap area. In other words, the pulse energy remains the same but the interbubble distance is adjusted.

The anterior interface is in particular the interface closer to the grain surface. The posterior interface is in particular the deeper interface and is therefore further away from the corneal surface.

According to an advantageous embodiment, the laser is controlled in such a way that a pulse energy of the laser is specified and, taking into account the minimum energy dose, a distance between adjacent cavitation bubbles is determined and adjusted by means of the control device. In this case, in particular, the distance between bubbles is to be regarded as the distance. In other words, at a given pulse energy of the laser, a maximum interbubble distance between the adjacent cavitation bubbles is determined, so that a minimum energy dose is generated on the cornea. This allows the solid body to be created efficiently and safely.

Furthermore, it can be provided that the laser is controlled in such a way that a distance between adjacent cavitation bubbles is specified and a pulse energy of the laser is determined and adjusted by means of the control device, taking into account the minimum energy dose. In other words, the interbubble distance between adjacent cavitation bubbles is specified. The pulse energy is then adjusted in such a way that a safe separation of the solid body can be carried out with a minimum energy dose, without bridges being created between the respective cavitation bubbles.

die Größe einer Kavitationsblase bestimmt werden. Wobei E_th der Mindestenergie zur Erzeugung der Kavitationsblase entspricht und E der eingesetzten Pulsenergie. Der Faktor K ist dabei abhängig von der Wellenlänge, der Pulsdauer sowie beispielsweise einer Größe einer Blendenöffnung der Behandlungsvorrichtung. In Abhängigkeit davon kann wiederum der Abstandsschwellwert bestimmt werden. Beispielsweise kann mittels der Formel: $$InterspotDistance=\frac{A}{2^{\mathrm{0,5}}}$$

der Zwischenblasenabstand derart bestimmt werden, dass keine Brücken zwischen den benachbarten Kavitationsblasen entstehen, wobei A im Wesentlichen einem Durchmesser der Kavitationsblase entspricht.It is also advantageous if, depending on the minimum energy dose, a distance threshold for a distance between adjacent cavitation bubbles and/or an energy threshold for a pulse energy of the laser is determined by means of the control device. In particular, the invention takes advantage of the fact that the size of the cavitation bubble increases with the cube root of the pulse energy. However, the pulse energy must at least exceed an energy threshold so that a cavitation bubble can be formed. Furthermore, it can be provided in particular that a distance threshold value between the intermediate bubble distance is specified. In particular, using the formula: $$bubbleSi\mathrm{e.g}e=K\ast \sqrt[3]{\left(E-E_{tH}\right)}$$

the size of a cavitation bubble can be determined. Where E _th corresponds to the minimum energy to generate the cavitation bubble and E to the pulse energy used. The factor K depends on the wavelength, the pulse duration and, for example, the size of an aperture opening of the treatment device. Depending on this, the distance threshold can again be determined. For example, using the formula: $$InterspOtDistance=\frac{A}{2^{0.5}}$$

the distance between bubbles can be determined in such a way that no bridges arise between the adjacent cavitation bubbles, where A essentially corresponds to a diameter of the cavitation bubble.

Furthermore, it can be provided that the laser is controlled in such a way that a geometry of the predetermined pattern is taken into account when generating the cavitation bubble using the control device. In particular, for example, a meandering generation of the pattern or a spiral formation of the predetermined pattern can be taken into account. In particular, interbubble distances between adjacent cavitation bubbles or interbubble distances between adjacent cavitation bubble paths can be taken into account in the specified pattern. This makes it possible for a minimum energy dose to be maintained even depending on the predefined pattern. Elliptical patterns or a helicoid pattern can also be used to create the Kavi tation bubbles are generated taking into account the minimum energy dose.

Furthermore, line jumps, for example, first a first cavitation bubble path and then a third cavitation bubble path are generated, can also be taken into account. For example, a meandering structure can be generated as a predetermined pattern, but the cavitation bubble path cannot be generated in sequence one after the other. In particular, the predefined pattern only emerges at the end of the treatment. For example, an internal cavitation bubble path can be generated first and then an external cavitation bubble path can be generated and subsequently cavitation bubble paths can be generated between the internal and the external cavitation bubble paths. After the individual cavitation bubble paths have been generated, the predetermined pattern, for example the meander shape, is then created. In particular, the minimum energy dose will also be taken into account here.

It is also advantageous if the laser is controlled in such a way that the geometry of the cavitation bubbles generated is specified as spherical and the laser is controlled in such a way that the spherical geometry of the cavitation bubbles is used when determining the overlap area and/or when determining a tolerance range for the overlap area is taken into account. In particular, this is because a corresponding cavitation bubble can only be generated at a predetermined energy density value. If this energy density value is exceeded, the cavitation bubble is generated, which in particular is essentially spherical and acts like a flat ellipse due to the closed cornea. The radius of the cavitation bubble is in particular approximately proportional to the cube root of the pulse energy. In particular, by specifying the cavitation bubble as spherical, the overlap area can be determined easily and yet reliably.

In particular, it can be provided that the cavitation bubble is described as, for example, elliptical, which does not deviate from a spherical shape. For example, the vertical length can vary from 50 percent to twice the lateral size. According to the invention, it is now possible to use the potential for generating different cavitation bubble sizes. For example, the energy can be adjusted such that the cavitation bubble exactly exceeds a distance between the cavitation bubbles or that the distance between the cavitation bubbles is adjusted so that they lie within the cavitation bubble boundaries.

It is also advantageous if the laser is controlled in such a way that a radius of the spherical geometry is specified as essentially proportional to the cube root of a pulse energy of a respective laser pulse and the overlap area and/or a tolerance range for the overlap area is determined depending on the predetermined radius. This enables an improved determination of the overlap area.

It is also advantageous if the laser is controlled in such a way that a distance range between a respective distance between the cavitation bubbles and an energy range for a respective pulse energy of the laser is specified. In other words, it can be provided that it is only possible to emit the laser pulses in the predetermined distance range and/or in the predetermined energy range. This makes it possible to ensure that the cavitation bubbles are generated reliably and at the same time, for example, that a predetermined energy range is not exceeded, so that no unwanted injuries to the eye can occur. The maximum distance in the distance area can also prevent the cavitation bubbles, for example, from being generated too “roughly”, which can lead to unwanted refractions within the treated cornea after the treatment. Thus, taking into account the minimum absorbed dose, the solid body can be reliably produced in such a way that the solid body can be produced with minimal injury.

For example, the energy range with the minimum pulse energy for generating a cavitation bubble can be specified. For example, the minimum pulse energy can be specified as E _th = 47 nJ.

It is also advantageous if the laser is controlled in such a way that topographical and/or pachymetric and/or morphological data of the cornea are taken into account. In particular, topographical and/or pachymetric measurements of the cornea to be treated as well as the type, location and extent of the, for example, pathological and/or unnatural altered area within the stroma of the cornea as well as corresponding ametropia of the eye can be taken into account. In particular, control data sets are created at least by providing topographical and/or pachymetric and/or morphological data of the untreated cornea and providing topographical and/or pachymetric and/or morphological data of the cornea to be removed pathological and/or unnaturally changed area within the cornea or taking into account appropriate optical corrections to correct the ametropia.

According to a further advantageous embodiment, the laser is controlled in such a way that the laser emits laser pulses in a wavelength range between 300 nanometers and 1400 nanometers, in particular between 700 nanometers and 1200 nanometers, with a respective pulse duration between 1 fs and 1 ns, in particular between 10 fs and 10 ps, and a repetition frequency greater than 10 kHz, in particular between 100 kHz and 100 MHz. Such lasers are already used for photodisruptive procedures in eye surgery. The produced lenticule, which corresponds to the solid body, is then removed through an incision in the cornea. The use of photodisruptive lasers in the method according to the invention also has the advantage that the cornea should not be irradiated in a wavelength range below 300 nm. In laser technology, this area is subsumed under the term “deep ultraviolet”. This advantageously prevents unintentional damage to the cornea from these very short-wave and high-energy rays. Photodisruptive lasers of the type used here usually introduce pulsed laser radiation with a pulse duration between 1 fs and 1 ns into the corneal tissue. As a result, the power density of the respective laser pulse required for the optical breakthrough can be spatially limited, so that a high cutting precision is guaranteed when producing the interfaces.

A second aspect of the invention relates to a treatment device with at least one eye surgical laser for the separation of a volume body with predefined interfaces of a human or animal eye by means of photodisruption and with at least one control device for the laser or lasers, which is designed to carry out the steps of the method according to the preceding one aspect to be carried out. The treatment device according to the invention makes it possible to reliably avoid disadvantages that occur when using conventional ablative treatment devices, namely relatively long treatment times and relatively high energy input by the laser into the cornea. These advantages are achieved in particular by designing the eye surgical laser as a photodisruptive laser.

The laser is suitable for producing laser pulses in a wavelength range between 300 nm and 1,400 nm, preferably between 700 nm and 1,200 nm, with a respective pulse duration between 1 fs and 1 ns, preferably between 10 fs and 10 ps, and a repetition frequency greater than 10 kHz, preferably between 100 kHz and 100 MHz.

In an advantageous embodiment of the treatment device, the treatment device has a storage device for at least temporarily storing at least one control data set, the control data set or sets comprising control data for positioning and / or focusing individual laser pulses in the cornea and at least one beam device for beam guidance and / or beam shaping and / or beam deflection and / or beam focusing of a laser beam of the laser. The control data sets mentioned are usually generated based on a measured topography and/or pachymetry and/or morphology of the cornea to be treated and the type of pathologically and/or unnaturally changed area within the cornea to be removed.

The beam device is designed in particular as a rotary scanner. The treatment device according to the invention makes it possible to reliably avoid disadvantages that occur when using conventional ablative treatment devices, namely relatively long treatment times and relatively high energy input by the laser into the cornea. These advantages are achieved in particular by designing the eye surgical laser as a photodisruptive laser.

Further features and their advantages can be found in the descriptions of the first aspect of the invention, with advantageous embodiments of each aspect of the invention being viewed as advantageous embodiments of the other aspect of the invention.

A third aspect of the invention relates to a computer program comprising instructions that cause the treatment device according to the second aspect of the invention to carry out the method steps according to the first aspect of the invention. A fourth aspect of the invention relates to a computer-readable medium on which the computer program according to the third aspect of the invention is stored. Further features and their advantages can be found in the descriptions of the first and second aspects of the invention, with advantageous embodiments of each aspect of the invention being viewed as advantageous embodiments of the other aspect of the invention.

Further features result 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 mentioned below in the description of the figures The features and feature combinations shown alone and/or in the figures alone can be used not only in the combination specified in each case, but also in other combinations without departing from the scope of the invention. Embodiments that are not explicitly shown and explained in the figures, but which emerge from the explained embodiments and can be generated by separate combinations of features are therefore also to be regarded as included and disclosed by the invention. Versions and combinations of features are also to be regarded as disclosed, which therefore do not have all the features of an originally formulated independent claim. In addition, versions and combinations of features, in particular through the statements set out above, are to be regarded as disclosed, which go beyond or deviate from the combinations of features set out in the references to the claims.

• 1 eine schematische Darstellung einer erfindungsgemäßen Behandlungsvorrichtung;
• 2 eine Prinzipdarstellung der Erzeugung eines abzutrennenden Volumenkörpers; und
• 3 eine schematische Draufsicht auf eine Grenzfläche eines Volumenkörpers.

Show:

• 1 a schematic representation of a treatment device according to the invention;
• 2 a schematic representation of the creation of a solid body to be separated; and
• 3 a schematic top view of an interface of a solid body.

In the figures, identical or functionally identical elements are provided with the same reference numerals.

1 shows a schematic representation of a treatment device 10 with an eye surgical laser 18 for the separation of a predefined corneal volume/corneal volume or volume body 12 with predefined interfaces 14, 16 of a cornea of a human or animal eye by means of photodisruption. It can be seen that, in addition to the laser 18, a control device 20 is designed for the laser 18, so that it emits pulsed laser pulses into the cornea, for example in a predefined pattern, the boundary surfaces 14, 16 of the solid body 12 to be separated being generated by the predefined pattern by means of photodisruption . In the exemplary embodiment shown, the boundary surfaces 14, 16 form a lenticle-like solid body 12, the position of the solid body 12 in this exemplary embodiment being chosen such that a pathological and/or unnaturally changed area 32 (see 2 ) is enclosed within a stroma 36 of the cornea. Furthermore is over 1 It can be seen that the so-called Bowman membrane 38 is formed between the stroma 36 and an epithelium 28.

Furthermore, it can be seen that the laser beam 24 generated by the laser 18 is deflected towards a surface 26 of the cornea by means of a beam device 22, namely a beam deflection device, such as a rotary scanner. The beam deflector is also controlled by the controller 20 to produce said predefined pattern in the cornea.

The laser 18 shown is a photodisruptive laser which is designed to emit laser pulses in a wavelength range between 300 nm and 1400 nm, preferably between 700 nm and 1200 nm, with a respective pulse duration between 1 fs and 1 ns, preferably between 10 fs and 10 ps, and a repetition frequency greater than 10 KHz, preferably between 100 KHz and 100 MHz.

The control device 20 also has a storage device (not shown) for at least temporarily storing at least one control data record 50 ( 3 ), wherein the control data set(s) 50 includes control data for positioning and/or focusing individual laser pulses in the cornea. The position data and/or focusing data of the individual laser pulses are based on a previously measured topography and/or pachymetry and/or the morphology of the cornea and the pathological and/or unnaturally changed area 32 to be removed, for example, or the optical vision correction to be created within the stroma 36 of the eye.

2 shows a schematic representation of the production of the solid body 12 to be separated according to an embodiment of the present method. It can be seen that the boundary surfaces 14, 16 are generated by means of the pulsed laser beam 24, which is directed via the beam deflection device 22 in the direction of the cornea or in the direction of the surface 26 of the cornea. The interfaces 14, 16 form a lenticular-like volume body 12, which, for example, encloses the pathological and/or unnaturally changed area 32 within the stroma 36. Furthermore, in the illustrated embodiment, the laser 18 produces a further cut 34, which cuts the solid body 12 at a predefined angle and with a predefined geometry and is formed up to the surface 26 of the cornea. The solid body 12 defined by the interfaces 14, 16 can then be removed from the cornea via the cut 34. In the illustrated embodiment, the pathological and/or unnaturally altered area 32 is within the stroma 36 and outside an optical axis 30 of an eye 40 ( 3 ) educated.

In the exemplary embodiment shown, the interface 14, that is to say the interface lying deeper in the eye 40 or the stroma 36, is first formed by means of the laser beam 24, this then corresponding to the posterior interface 14. This can be done by at least partially circular and/or spiral guidance of the laser beam 24 according to the predefined pattern. The interface 16 is then created in a comparable manner, which then corresponds to the anterior interface 16, so that the interfaces 14, 16 form the lenticle-shaped solid body 12 (see also 1 ) train. The cut 34 is then also generated with the laser 18. However, the order of creating the interfaces 14, 16 and the cut 34 can also be changed.

3 shows a schematic plan view of one of the interfaces 14, 16 of the solid body 12 with a large number of cavitation bubbles 40. In the present case, the solid body 12 is shown purely schematically and serves only to illustrate the method. In particular, the solid body 12 has more than the cavitation bubbles 40 shown. That in the 3 The example shown is therefore only to be understood schematically and should in no way be considered conclusively. It merely serves to illustrate the idea according to the invention. In particular, a predefined pattern 42 has not yet been created. The solid body 12 shown is therefore in an intermediate stage during the treatment.

In particular, it shows 3 that in the method for controlling the eye surgical laser 18 of the treatment device 10 for the separation of the solid body 12 with the predefined posterior interface 14 and the predefined anterior interface 16 from a human or animal cornea, the laser 18 is controlled by means of the control device 20 of the treatment device 10 in such a way This is done by emitting pulsed laser pulses into the cornea in a shot sequence in the predefined pattern 42, which in the present case is shown in particular in a meandering shape, the boundary surfaces 14, 16 of the solid body 12 to be separated being defined by the predefined pattern 42 and the boundary surfaces 14, 16 by means of the interaction of the individual laser pulses with the cornea by generating the plurality of cavitation bubbles 40 generated by photodisruption, the plurality of cavitation bubbles 40 being generated along at least one cavitation bubble path 44 of the predefined pattern 42, the cavitation bubbles 40 being generated by specifying a minimum energy dose 46 are generated on the cornea.

For this purpose, it can be provided, for example, that the laser 18 is controlled in such a way that a pulse energy 48 of the laser 18 is specified and, taking into account the minimum energy dose 46, a distance 50 between adjacent cavitation bubbles 40 is determined and adjusted by means of the control device 20. A so-called intermediate bubble distance can be viewed as the distance 50 in particular. The distance between bubbles is determined in particular by the distance between the respective centers of the cavitation bubbles 40.

Furthermore, it shows 3 that the laser 18 can be controlled in such a way that the distance 50 between the adjacent cavitation bubbles 40 is specified and, taking into account the minimum energy dose 46, the pulse energy 48 of the laser 18 can be determined and adjusted by means of the control device 20.

Furthermore, it can be provided in particular that, depending on the minimum energy dose 46, a distance threshold value for the distance 50 between the adjacent cavitation bubbles 40 and/or an energy threshold value for the pulse energy 48 of the laser 18 is determined by means of the control device 20.

In particular, it is shown that the laser 18 is controlled in such a way that a geometry of the predetermined pattern 42, in this case in particular the meandering geometry, is taken into account when generating the cavitation bubbles 40 by means of the control device 20. In addition to the meandering geometry, an ellipsoidal geometry or a helicoidal geometry can also be taken into account. In particular, the invention further uses the fact that the control of the laser 18 can take place in such a way that the geometry of the cavitation bubbles 40 generated is specified as spherical and the control of the laser 18 takes place in such a way that the spherical geometry of the cavitation bubbles 40 is taken into account.

Furthermore, the invention makes use of the fact that the laser 18 is controlled in such a way that the geometry of the cavitation bubbles 40 generated is specified as spherical and the laser 18 is controlled in such a way that the spherical geometry of the cavitation bubbles 40 is taken into account. For this purpose, for example, a radius of spherical geometry can be specified as essentially proportional to the cube root of the pulse energy 48 of a respective laser pulse and, depending on the specified radius A, an overlap area 52 of the cavitation bubbles 40 can be determined, the specific overlap area 52 being used in the generation of the cavitation blows 40 taking into account the minimum absorbed dose 46.

Furthermore, it can be provided in particular that the control of the laser 18 takes place in such a way that a distance range for a respective distance 50 between the cavitation bubbles 40 and an energy range for a respective pulse energy 48 of the laser 18 are specified. In other words, it can be provided that it is only possible to emit the laser pulses in the predetermined distance range and/or in the predetermined energy range. This can ensure that the cavitation bubbles 40 are generated reliably and at the same time, for example, that a predetermined energy range is not exceeded, so that no unwanted injuries to the eye can occur. The maximum distance in the distance range can also prevent the cavitation bubbles 40, for example, from being generated too “roughly”, which can lead to unwanted refractions within the treated cornea after the treatment. Thus, taking into account the minimum energy dose 46, the solid body 12 can be reliably generated in such a way that the solid body 12 can be generated with minimal injury. For example, the energy range with the minimum pulse energy 48 for generating a cavitation bubble 40 can be specified. For example, the minimum pulse energy can be specified as E _th = 47 nJ.

Overall, the show 1 to 3 how the solid body 12 can be reliably generated while maintaining a minimum energy dose for the generation of the cavitation bubbles 40.

Claims (14)

Method for controlling an eye surgical laser (18) of a treatment device (10) for the separation of a volume body (12) with a predefined posterior interface (14) and a predefined anterior interface (16) from a human or animal cornea, comprising: - Controlling the laser (18) by means of a control device (20) of the treatment device (10) in such a way that it emits pulsed laser pulses in a shot sequence in a predefined pattern (42) into the cornea, the interfaces (14, 16) of the solid body to be separated (12) are defined by the predefined pattern (42) and the interfaces (14, 16) are generated by means of an interaction of the individual laser pulses with the cornea by generating a large number of cavitation bubbles (40) generated by photodisruption, the cavitation bubbles (40) can be generated in the cornea by specifying a minimum absorbed dose (46), the absorbed dose (46) indicating an average energy delivered to the cornea by the laser beams based on the mass of the irradiated cornea volume. Procedure according to Claim 1 , characterized in that the laser (18) is controlled in such a way that a pulse energy (48) of the laser (18) is specified and, taking into account the minimum energy dose (46), a distance (50) between adjacent cavitation bubbles (40) is determined by means of the Control device (20) is determined. Procedure according to Claim 1 , characterized in that the laser (18) is controlled in such a way that a distance (50) between adjacent cavitation bubbles (40) is specified and, taking into account the minimum energy dose (46), a pulse energy (48) of the laser (18) is determined by means of the Control device (20) is determined. Method according to one of the preceding claims, characterized in that, depending on the minimum energy dose (46), a distance threshold value for a distance (50) between adjacent cavitation bubbles (40) and / or an energy threshold value for a pulse energy (48) of the laser (18) can be determined by means of the control device (20). Method according to one of the preceding claims, characterized in that the laser (18) is controlled in such a way that a geometry of the predetermined pattern (42) is taken into account when generating the cavitation bubbles (40) by means of the control device (20). Method according to one of the preceding claims, characterized in that the laser (18) is controlled in such a way that the geometry of the cavitation bubbles (40) generated is specified as spherical and the laser (18) is controlled in such a way that the spherical geometry of the Cavitation bubbles (40) are taken into account. Procedure according to Claim 6 , characterized in that the laser (18) is controlled in such a way that a radius of the spherical geometry is specified as essentially proportional to the cube root of a pulse energy (48) of a respective laser pulse and, depending on the specified radius, an overlap area (52) of the cavitation bubbles (40) is determined, the specific overlap area (52) being taken into account when generating the cavitation bubbles (40), taking into account the minimum absorbed dose (46). Method according to one of the preceding claims, characterized in that the laser (18) is controlled in such a way that a distance range for a respective distance (50) between the cavitation bubbles (40) and an energy range for a respective pulse energy (48) of the laser ( 18) can be specified. Method according to one of the preceding claims, characterized in that the laser (18) is controlled in such a way that topographical and/or pachymetric and/or morphological data of the cornea are taken into account. Method according to one of the preceding claims, characterized in that the laser (18) is controlled in such a way that the laser (18) emits laser pulses in a wavelength range between 300 nm and 1400 nm, in particular between 700 nm and 1200 nm, at a respective pulse duration between 1 fs and 1 ns, in particular between 10 fs and 10 ps, and a repetition frequency greater than 10 kHz, in particular between 100 kHz and 10MHz. Treatment device (10) with at least one surgical laser (18) for the separation of a solid body (12) with predefined interfaces (14, 16) of a human or animal eye by means of photodisruption and with at least one control device (20) for the laser or lasers (18 ), which is designed to carry out the steps of the method according to one of the Claims 1 until 10 to carry out. Treatment device (10). Claim 11 , characterized in that the control device - has at least one storage device for at least temporary storage of at least one control data set, the control data set or sets comprising control data for positioning and / or focusing individual laser pulses in the cornea; and - at least one beam device (22) for beam guidance and/or beam shaping and/or beam deflection and/or beam focusing of a laser beam (24) of the laser (18). Computer program, comprising commands that cause the treatment device (10) according to Claim 11 or 12 the procedural steps according to one of the Claims 1 until 10 executes. Computer-readable medium on which the computer program is written Claim 13 is stored.

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