Patent Description:
For the purposes of working on eye tissue by means of a laser beam, a work region is scanned by laser pulses by virtue of the pulsed laser beam being deflected in one or more scan directions by means of suitable scanner systems. In general, movable mirrors are used to deflect the light beams and/or the laser pulses, for example femtosecond laser pulses, said movable mirrors being pivotable about one or two scan axes, for example by way of galvano scanners, piezo scanners, polygon scanners, or resonance scanners.

<CIT> describes an apparatus for working on eye tissue, said apparatus having a base station with a laser source for producing laser pulses and a scanner, arranged in the base station, with movable deflection mirrors for deflecting the laser pulses in a scan direction. The deflected laser pulses are transferred via an optical relay system from the base station to an application head, the latter passing over a work region according to a scan pattern by means of a mechanically moved projection optical unit. According to <CIT>, in the application head, the deflection in the scan direction, which is much faster in comparison with the mechanical movement, is overlaid onto the mechanical movement of the projection optical unit and consequently onto the scan pattern thereof.

A fast scanner system in the base station facilitates a fine movement of the laser pulses (micro-scan), which is overlaid on the scan pattern of the movable projection optical unit that covers a large work region, for example the entire eye.

For refractive correction, pulsed laser radiation is used in corneal surgery to create a lenticule in the cornea. To achieve the refractive correction, the created lenticule is subsequently removed from the cornea through an extraction channel cut in the cornea.

<CIT> describes a system and a method for cutting lenticules in the eye tissue. According to <CIT>, straight-lined fast scan lines are overlaid to this end on slower work lines that are traced out along meridians of the lenticule.

Using femtosecond laser pulses to generate cuts inside the cornea produces gas inside the cornea. As this gas produces cloudy areas in the cornea, it may impair the quality of subsequent neighbouring or overlapping cuts and thereby compromise significantly the quality of the cut surface and the intended refractive correction. To alleviate the negative impact of gas produced during the cutting process, <CIT> and <CIT> teach the cutting of venting pockets inside the cornea which receive and collect the unwanted gas. Nevertheless, when lenticules are cut inside the cornea for refractive correction, these venting pockets may still have a negative impact as the build-up of pressure by the gas inside the venting pockets may be detrimental to the precision of corneal cuts which is absolutely required for refractive correction.

<CIT> describes a device for surgical laser treatment of a cornea whereby a partial volume of a cornea is cut inside the cornea and removed from the cornea through an opening which is cut up to the surface of the cornea.

<CIT> describes a device for cornea reshaping by intrastromal tissue removal whereby first a micro-channel of a very small diameter, e.g. <NUM>-<NUM> or <NUM>-<NUM>, is cut in the cornea by means of a laser beam, and subsequently the laser beam is passed through the channel and focused at the desired location to ablate a disc of corneal tissue inside the cornea. <CIT> teaches that the micro-channel provides a means of self-removal of the ablated tissue in the form of gas and liquid under the over-pressure created within the ablated volume. According to <CIT>, such small channels will usually close without further intervention in a matter of minutes after the process of photoablation is completed.

<CIT> describes a device for use in a laser-assisted eye-surgery whereby a flap is cut into the cornea or a corneal lenticule is cut to be extracted from the cornea. For the case of the flap, <CIT> further teaches to cut into the cornea a substantially flat auxiliary incision which is cut prior to the corneal flap and serves as a degassing channel, through which surgical gases that arise in the course of cutting the corneal flap can be vented. According to <CIT>, this auxiliary incision is connected to the incision for the flap and terminates on the surface of the eye. <CIT> further teaches an applicator with a contact element <NUM> for fixing the eye in a coordinate system of the treatment system.

<CIT> describes corneal surgical devices and is related to stabilizing lenticules cut in the cornea for refractive correction. <CIT> teaches cutting channels in the cornea to facilitate the removal of a lenticule from the cornea. According to <CIT> the channels further facilitate application of a stabilization solution to the lenticule to stabilize the lenticule.

It is an object of the present disclosure to propose an ophthalmological device for surgical treatment of a cornea of an eye using a pulsed laser beam, which device does not have at least some of the disadvantages of the prior art. Particularly, it is an object of the present disclosure to propose an ophthalmological device for surgical treatment of a cornea of an eye using a pulsed laser beam, which device at least reduces the detrimental impact of gas produced when a lenticule is cut inside the cornea using the pulsed laser beam.

According to the present disclosure, these objects are achieved by the features of the independent claims. Moreover, further advantageous embodiments emerge from the dependent claims and the description.

An ophthalmological device for surgical treatment of a cornea of an eye comprises: a laser source configured to generate a pulsed laser beam; a focusing optical module configured to make the pulsed laser beam converge onto a focus in the cornea; a scanner system configured to move the focus to target locations in the cornea; and an electronic circuit configured to control the scanner system to move the focus to cut inside the cornea a lenticule, the lenticule having a posterior lenticule surface and an anterior lenticule surface.

According to the present disclosure, the above-mentioned objects are particularly achieved in that the electronic circuit is further configured to control the scanner system to move the focus to cut in the cornea a venting channel, the venting channel comprising an opening incision in a peripheral area of an exterior surface of the cornea, outside a perimeter of the lenticule from a top view perspective onto the cornea, and the venting channel connecting fluidically at least one of the posterior lenticule surface or the anterior lenticule surface to the opening incision, to enable venting of a gas, produced by cutting the lenticule inside the cornea, through the opening incision to the exterior of the cornea.

In an embodiment, the ophthalmological device comprises a measurement system configured to determine positional reference data of the cornea, and the electronic circuit is configured to control the scanner system to move the focus to cut the venting channel, using the positional reference data. The positional reference data of the cornea is particularly useful for positioning the opening incision of the venting channel in the peripheral area of the exterior surface of the cornea, outside the perimeter of the lenticule from the top view perspective onto the cornea.

In an embodiment, the ophthalmological device further comprises a patient interface, the patient interface comprising an applanation body and one or more suction elements configured to fix the applanation body to the cornea for applanating the cornea in an applanation zone where the applanation body is in contact with the exterior surface of the cornea; and the electronic circuit is configured to control the scanner system to move the focus to cut in the cornea the venting channel with the opening incision located in a peripheral area of the exterior surface of the cornea outside the applanation zone.

In an embodiment, the patient interface comprises a fastening ring encompassing the applanation body, the one or more suction elements are arranged in the fastening ring and connected fluidically to a suction pump, and in the state where the patient interface is fixed to the cornea, the fastening ring and the applanation body form an external venting chamber with the peripheral area of the exterior surface of the cornea, outside the applanation zone; and the electronic circuit is configured to control the scanner system to move the focus to cut in the cornea the venting channel with the opening incision leading to the inside of the external venting chamber.

In an embodiment, the ophthalmological device further comprises a measurement system configured to determine positional reference data of the cornea in an applanated state of the cornea, and the electronic circuit is configured to control the scanner system to move the focus to cut the venting channel, using the positional reference data to position the opening incision of the venting channel in the peripheral area of the exterior surface of the cornea outside the applanation zone.

In an embodiment, the measurement system comprises a video capturing system and/or an optical coherence tomography system.

In an embodiment, the electronic circuit is configured to control the scanner system to move the focus to cut in the cornea an extraction channel, the extraction channel comprising an extraction incision in the exterior surface of the cornea, and the extraction channel connecting the lenticule to the extraction incision to enable extraction of the lenticule through the extraction incision to the exterior of the cornea; and to control the scanner system to move the focus to cut the venting channel partially coinciding with the extraction channel.

In an embodiment, the electronic circuit is configured to control the scanner system to move the focus along a work trajectory to cut the venting channel and at least one of the posterior lenticule surface or the anterior lenticule surface in a continuous movement of the focus along the work trajectory.

In an embodiment, the electronic circuit is configured to control the scanner system to move the focus to cut the venting channel from the opening incision to a perimeter of the lenticule, the perimeter being defined by an intersection of the posterior lenticule surface and the anterior lenticule surface.

In an embodiment, the electronic circuit is configured to control the scanner system to move the focus along a tangential trajectory for cutting the venting channel, whereby the tangential trajectory runs tangentially onto a perimeter of the lenticule.

In an embodiment, the electronic circuit is configured to control the scanner system to move the focus along a spiral shaped trajectory to cut at least one of the posterior lenticule surface or the anterior lenticule surface, and to move the focus along a straight trajectory that leads onto the spiral shaped trajectory to cut the venting channel along the straight trajectory.

In an embodiment, the electronic circuit is configured to control the scanner system to move the focus along a radial trajectory directed towards a central axis of the lenticule to cut the venting channel along the radial trajectory.

In an embodiment, the electronic circuit is configured to control the scanner system to move the focus to cut the venting channel with a channel width which increases from the lenticule to the opening incision.

In an embodiment, the electronic circuit is configured to control the scanner system to move the focus to cut in the cornea a first venting channel, the first venting channel comprising a first opening incision in the exterior surface of the cornea, and the first venting channel connecting the posterior lenticule surface to the first opening incision, to enable venting of a gas produced by cutting the posterior lenticule surface through the first opening incision to the exterior of the cornea, and to cut in the cornea a second venting channel, the second venting channel comprising a second opening incision in the exterior surface of the cornea, and the second venting channel connecting the anterior lenticule surface to the second opening incision, to enable venting of a gas produced by cutting the anterior lenticule surface through the second opening incision to the exterior of the cornea.

In addition to the ophthalmological device for surgical treatment of a cornea of an eye, the present disclosure further relates to a computer program product, particularly, a computer program product comprising a non-transitory computer-readable medium having stored thereon computer program code for controlling a processor of an ophthalmological device which comprises a laser source configured to generate a pulsed laser beam, a focusing optical module configured to make the pulsed laser beam converge onto a focus in the cornea, and a scanner system configured to move the focus to target locations in the cornea. The computer program code is configured to control the processor such that the processor directs the scanner system to move the focus to cut inside the cornea a lenticule, the lenticule having a posterior lenticule surface and an anterior lenticule surface, and to move the focus to cut in the cornea a venting channel, the venting channel comprising an opening incision in a peripheral area of an exterior surface of the cornea, outside a perimeter of the lenticule from a top view perspective onto the cornea, and the venting channel connecting fluidically at least one of the posterior lenticule surface or the anterior lenticule surface to the opening incision, to enable venting of a gas produced by cutting the lenticule inside the cornea through the opening incision to the exterior of the cornea.

The present disclosure will be explained in more detail, by way of example, with reference to the drawings in which:.

In <FIG>, reference numeral <NUM> relates to an ophthalmological device for surgical treatment of a cornea <NUM> of an eye <NUM> with a pulsed laser beam B.

As illustrated schematically in <FIG>, the ophthalmological device <NUM> comprises a laser source <NUM> for generating the pulsed laser beam B, a focusing optical module <NUM> for focusing the pulsed laser beam B in the cornea <NUM> onto a focus F, and a scanner system <NUM> for moving the focus F to target locations in the cornea <NUM>.

In particular, the laser source <NUM> comprises a femtosecond laser for producing femtosecond laser pulses, which have pulse widths of typically <NUM> fs to <NUM> fs (<NUM> fs = <NUM>-<NUM> s). The laser source <NUM> is arranged in a separate housing or in a housing shared with the focusing optical module <NUM>.

The focusing optical module <NUM> is configured to focus the pulsed laser beam B or the laser pulses, respectively, in the cornea <NUM> onto a focus F, i.e. for making the pulsed laser beam B converge to a focal point or spot in the cornea <NUM>. The focusing optical module <NUM> comprises one or more optical lenses. In an embodiment, the focusing optical module <NUM> comprises a focus adjustment device for setting the focal depth of the focus F, for example one or more movable lenses, in the focusing optical module <NUM> or upstream of the focusing optical module <NUM>, or a drive for moving the entire focusing optical module <NUM> along the projection axis p (z-axis). By way of example, the focusing optical module <NUM> is installed in an application head <NUM>, which can be placed onto the eye <NUM>.

As illustrated schematically in <FIG>, the ophthalmological device <NUM> comprises a patient interface <NUM> for attaching the application head <NUM> or the focusing optical module <NUM>, respectively, onto the eye <NUM>. Depending on the embodiment, the patient interface <NUM> is connected to the application head <NUM> in a fixed or removable manner.

The patient interface <NUM> comprises an applanation body <NUM> and one or more suction elements configured to fix the applanation body <NUM> and thus the patient interface <NUM> to the cornea <NUM>. For example, the one or more suction elements are arranged in a fastening ring <NUM>, e.g. a vacuum-controlled suction ring, whereby the one or more suction elements are connected fluidically to a suction pump. The applanation body <NUM>, also referred to as contact body, is at least partly light-transparent.

As illustrated in <FIG>, in the state where the patient interface <NUM> or the applanation body <NUM>, respectively, is fixed to the cornea <NUM>, specifically to the exterior (anterior) surface A of the cornea <NUM>, applanated is an applanation zone Az of the cornea <NUM>, where the applanation body <NUM> is in contact with the exterior (anterior) surface A of the cornea <NUM>.

As is further illustrated in <FIG> and also indicated in <FIG>, in the state where the patient interface <NUM> or the applanation body <NUM>, respectively, is fixed to the cornea <NUM>, the fastening ring <NUM> and the applanation body <NUM> form an external venting chamber <NUM> with the peripheral area Ap of the exterior (anterior) surface A of the cornea <NUM> outside the applanation zone Az. The venting chamber <NUM> is defined by an interior wall 16i of the fastening ring <NUM>, the surface of the applanation body <NUM> contacting the cornea <NUM>, and the peripheral area Ap of the exterior (anterior) surface A of the cornea <NUM> outside the applanation zone Az.

The scanner system <NUM> is configured to move the focus F to target locations in the cornea <NUM> by guiding and directing the pulsed laser beam B and thus the focus F to target locations in the cornea <NUM>. The scanner system <NUM> comprises one or more scanner modules configured to guide and direct the pulsed laser beam B and thus the focus F in a x/y-work-plane which is normal to a z-axis, whereby the z-axis is aligned with or essentially parallel to the projection axis p of the focusing optical module <NUM>, as illustrated schematically in <FIG>. Depending on the embodiment, the one or more scanner modules comprise one or more actuators configured to move the focusing optical module <NUM> such that the focus F is moved along a work line in the x/y-work-plane, and/or one or more deflection mirrors, each movable about one or two axes, configured to deflect the pulsed laser beam B and/or the laser pulses such that the focus F is moved along the work line in the x/y-work-plane. The scanner system <NUM> further comprises a z-modulator configured to move the focus F along the z-axis which is aligned with or essentially parallel to the projection axis p of the focusing optical module <NUM>. For example, the z-modulator comprises a divergence modulator configured to dynamically change the divergence of the pulsed laser beam B. Various further and more specific embodiments of the scanner system <NUM> are described by the applicant in patent applications <CIT>, <CIT>, and <CIT>.

The ophthalmological device <NUM> further comprises an electronic circuit <NUM> for controlling the laser source <NUM> and the scanner system <NUM>. The electronic circuit <NUM> implements a programmable control device and comprises e.g. one or more processors <NUM> with program and data memory and programmed software modules for controlling the processors <NUM>, and/or other programmable circuits or logic units such as ASICs (application specific integrated circuits).

In an embodiment, the ophthalmological device <NUM> further comprises a measurement system <NUM> configured to determine positional reference data of the cornea <NUM>. Depending on the embodiment, the measurement system <NUM> comprises a video capturing system, an optical coherence tomography (OCT) system, and/or a structured light illumination system. Accordingly, the measurement data or positional reference data determined by the measurement system <NUM> includes video data, including top view data (comprising two-dimensional images), and/or OCT data of the cornea <NUM> (comprising three-dimensional tomography data). The measurement system <NUM> is configured to determine the positional reference data of the cornea <NUM> also in an applanated state of the cornea <NUM>. The measurement system <NUM> is connected to and/or integrated with the electronic circuit <NUM> which is further configured to control the scanner system <NUM>, using the positional reference data from the measurement system <NUM>. For example, the measurement system <NUM> and/or the electronic circuit <NUM> are configured to determine as further positional reference data the peripheral area Ap of the exterior (anterior) surface A of the cornea <NUM> outside the applanation zone Az, using the measurement data or the positional reference data captured by the measurement system <NUM>.

The electronic circuit <NUM> is configured to control the scanner system <NUM> to move the focus F to cut inside the cornea <NUM> a lenticule L which has a posterior lenticule surface Lp and an anterior lenticule surface La, as illustrated in <FIG>. For example, the electronic circuit <NUM> is configured to control the scanner system <NUM> to move the focus F to cut the lenticule L inside the cornea <NUM> as described by the applicant in patent applications <CIT>, <CIT>, and <CIT>.

The electronic circuit <NUM> is further configured to control the scanner system <NUM> to move the focus F to cut in the cornea <NUM> one or more venting channels Ch, Ch1, Ch2, as illustrated in <FIG>. These venting channels Ch, Ch1, Ch2, in <FIG> provide a fluidic connection from the posterior lenticule surface Lp and/or the anterior lenticule surface La to respective opening incisions Co, Co1, Co2 in the exterior (anterior) surface A of the cornea <NUM>. As illustrated in <FIG>, the venting channels Ch, Ch1, Ch2 comprise an opening incision Co, Co1 , Co2 in a peripheral area of the exterior (anterior) surface A of the cornea <NUM>, outside a perimeter of the lenticule L when viewed from a top view perspective (along the z-axis or the projection axis p, respectively) onto the cornea <NUM>. The venting channels Ch, Ch1, Ch2 connect fluidically the lenticule L, specifically the posterior lenticule surface Lp and/or the anterior lenticule surface La, through the respective opening incisions Co, Co1 , Co2 in the exterior (anterior) surface A of the cornea <NUM> to the exterior of the cornea <NUM>.

The fluidic venting channels Ch, Ch1, Ch2 enable venting of gas, produced by (laser) cutting the lenticule L inside the cornea <NUM>, through the respective opening incisions Co, Co1, Co2 to the exterior of the cornea <NUM>. The venting channels Ch, Ch1, Ch2 have a channel width d, d1, d2 defined by the width of the cut surface forming the venting channels Ch, Ch1, Ch2. As can be seen in <FIG>, the channel width d, d1, d2 is defined by the extension of the cut surfaces forming the venting channels Ch, Ch1, Ch2 in a horizontal x/y-working plane. The channel width d, d1, d2 of the venting channels Ch, Ch1, Ch2 is far smaller than the length of the venting channels Ch, Ch1, Ch2, extending from the respective opening incisions Co, Co1, Co2 to the lenticule L. The relatively smaller channel widths d, d1, d2 or diameter of the cross-sectional profile of the venting channels Ch, Ch1, Ch2 is in the range of <NUM> to <NUM>, preferably in the range of <NUM> to <NUM>, whereas the length of the venting channels Ch, Ch1, Ch2 is in the range of <NUM> to <NUM>. In an embodiment, the venting channels Ch, Ch1, Ch2 are cut with a cross-shaped cross sectional profile of the venting channels Ch, Ch1, Ch2.

The electronic circuit <NUM> is further configured to control the scanner system <NUM> to move the focus F to cut in the cornea <NUM> the one or more venting channels Ch, Ch1, Ch2 from the outside to the inside of the cornea <NUM>, i.e. commencing from the respective opening incision Co, Co1, Co2 in the exterior (anterior) surface A of the cornea <NUM> through the cornea tissue to the lenticule L inside the cornea <NUM>.

In an embodiment, the electronic circuit <NUM> is further configured to control the laser source <NUM> to set and use a comparatively higher energy level for cutting the opening incisions Co, Co1, Co2 in the exterior (anterior) surface A of the cornea <NUM>, and to reduce the energy level for cutting the venting channels Ch, Ch1, Ch2 beyond the opening incision Co, Co1, Co2.

It should be pointed out that cutting the one or more venting channels Ch, Ch1, Ch2 from the outside to the inside of the cornea produces gas which at least partially remains in the venting channels Ch, Ch1, Ch2 and keeps the venting channels Ch, Ch1, Ch2 open.

As is shown in <FIG>, the opening incisions Co, Co1, Co2 of the venting channels Ch, Ch1, Ch2 are arranged in a peripheral area Ap of the exterior (anterior) surface A of the cornea <NUM>, outside the applanation zone Az. Thus, the fluidic venting channels Ch, Ch1, Ch2 enable the venting of the gas, produced by (laser) cutting the lenticule L inside the cornea <NUM>, through the respective opening incisions Co, Co1, Co2 to the exterior of the cornea <NUM> outside the applanation zone Az. More specifically, the opening incisions Co, Co1, Co2 of the venting channels Ch, Ch1, Ch2 are arranged in a peripheral area Ap of the exterior (anterior) surface A of the cornea <NUM> bordering onto the venting chamber <NUM>. Thus, the fluidic venting channels Ch, Ch1, Ch2 enable the venting of the gas, produced by (laser) cutting the lenticule L inside the cornea <NUM>, through the respective opening incisions Co, Co1, Co2 into the venting chamber <NUM>.

In an embodiment, the one or more suction elements of the fastening ring <NUM> apply - interruptedly or non-interruptedly - a partial vacuum to the venting chamber <NUM> and thereby further facilitate the venting of the gas, build-up by cutting the lenticule L in the cornea <NUM>, through the fluidic venting channels Ch, Ch1, Ch2 and their respective opening incisions Co, Co1, Co2 to the exterior of the cornea <NUM>, outside the applanation zone Az, into the venting chamber <NUM>.

In an embodiment, the electronic circuit <NUM> is configured to use the positional reference data from the measurement system <NUM> to control the scanner system <NUM> to move the focus F to cut in the cornea <NUM> the one or more venting channels Ch, Ch1, Ch2. For example, the electronic circuit <NUM> is configured to determine from the measurement data or the positional reference data, respectively, the peripheral area Ap of the exterior (anterior) surface A of the cornea <NUM>, outside the applanation zone Az. More specifically, the electronic circuit <NUM> is configured to determine from the measurement data or the positional reference data, respectively, the peripheral area Ap of the exterior (anterior) surface A of the cornea <NUM>, outside the applanation zone Az and bordering onto the venting chamber <NUM>. Moreover, the electronic circuit <NUM> is configured to determine the location of the opening incisions Co, Co1 , Co2 inside the peripheral area Ap of the exterior (anterior) surface A of the cornea <NUM>. In an embodiment, the electronic circuit <NUM> is configured to receive operator input, e.g. via a data entry element and/or a touchscreen, for selecting, moving, and/or positioning the location of the opening incisions Co, Co1, Co2 within the peripheral area Ap of the exterior (anterior) surface A of the cornea <NUM>,.

Furthermore, the electronic circuit <NUM> is configured to control the scanner system <NUM> to move the focus F to cut in the cornea <NUM> one or more "mechanical" extraction channels I, as illustrated in <FIG>. As illustrated, an extraction channel I comprises an extraction incision Co3 in the exterior (anterior) surface A of the cornea <NUM>. The extraction channel I connects the lenticule L to the extraction incision Co3 and enables mechanical extraction of the lenticule L from the cornea <NUM> through the extraction incision Co3 to the exterior of the cornea <NUM>. Thus, compared to the channel widths d, d1, d2 of the fluidic venting channels Ch, Ch1, Ch2, the mechanical extraction channel I has much greater channel width d3, e.g. in the range of <NUM> to <NUM>. On the other hand, compared to the channel lengths of the fluidic venting channels Ch, Ch1, Ch2, the mechanical extraction channel I has much shorter channel length, e.g. in the range of <NUM> to <NUM>.

In an embodiment, the electronic circuit <NUM> is configured to control the scanner system <NUM> to move the focus F to cut in the cornea <NUM> the one or more venting channels Ch, Ch1, Ch2 partially coinciding with the extraction channel I.

In the following paragraphs, different embodiments and/or configurations of the venting channels Ch, Ch1, Ch2 are described with reference to <FIG>, whereby <FIG> shows a cross-sectional view of the venting channels Ch1, Ch2, and <FIG> show top views of the venting channels Ch, Ch1, Ch2. For the sake of clarity, it is pointed out here that the electronic circuit <NUM> is configured to control the scanner system <NUM> to move the focus F to cut the venting channels Ch, Ch1, Ch2 in the cornea <NUM> to produce one or more of these embodiments and/or configurations and combinations thereof, for example, as selected or selectable by an operator. Furthermore, it is pointed out that <FIG> and <FIG> show two venting channels Ch1, Ch2 with their respective opening incisions Co1, Co2, but that in different scenarios both or only one of these two venting channels Ch1, Ch2 may actually be cut, e.g. as selected by the operator.

Although it is only clearly visible in <FIG>, it should be pointed out that all venting channels Ch, Ch1, Ch2 comprise an opening incision Co, Co1, Co2 within the peripheral area Ap of the exterior (anterior) surface A of the cornea <NUM>, outside the applanation zone Az and bordering onto the venting chamber <NUM>, such as to enable venting of gas through the venting channels Ch, Ch1, Ch2 and the respective opening incision Co, Co1, Co2 into the venting chamber <NUM>.

<FIG> show scenarios where the electronic circuit <NUM> is configured to control the scanner system <NUM> to move the focus F to cut the venting channel Ch, Ch1, Ch2 in the cornea <NUM> from the respective opening incision Co, Co1, Co2 to a perimeter q of the lenticule L. As illustrated in <FIG>, the perimeter q of the lenticule L is defined by the intersection of the posterior lenticule surface Lp and the anterior lenticule surface La.

<FIG> shows a scenario where the electronic circuit <NUM> is configured to control the scanner system <NUM> to move the focus F along a radial trajectory r1, r2 directed towards a central axis z of the lenticule L to cut one or more of the venting channels Ch1, Ch2 along the respective radial trajectory r1, r2. As illustrated in <FIG>, the radial trajectories r1, r2 are orientated at different angles α, β, e.g. with respect to a reference axis in the x/y-work plane, e.g. with respect to the x-axis, e.g. selected or set by the operator. As further illustrated in <FIG>, the venting channels Ch1, Ch2 have different channel widths d1, d2, e.g. selected or set by the operator.

Contrary to <FIG>, where the venting channel Ch has a constant channel width d from the opening incision Co to the perimeter q of the lenticule L, <FIG> shows a scenario where the electronic circuit <NUM> is configured to control the scanner system <NUM> to move the focus F to cut the venting channel Ch with a channel width which increases from the lenticule L to the opening incision Co, starting with a comparatively smaller channel width e onto the perimeter q of the Lenticule L and increasing to a comparatively wider channel width d at the opening incision Co.

<FIG> shows a scenario where the electronic circuit <NUM> is configured to control the scanner system <NUM> to move the focus F along a tangential trajectory t to cut the venting channel Ch, whereby the tangential trajectory t runs tangentially onto a perimeter q of the lenticule L.

<FIG> shows a scenario where the electronic circuit <NUM> is configured to control the scanner system <NUM> to move the focus F along a work trajectory w, e.g. a spiral shaped work trajectory w, to cut the venting channel Ch and the posterior lenticule surface Lp and/or the anterior lenticule surface La of the lenticule L in a continuous movement of the focus F along the work trajectory w.

<FIG> shows a scenario where the electronic circuit <NUM> is configured to control the scanner system <NUM> to move the focus F along a spiral shaped work trajectory w, to cut the posterior lenticule surface Lp and/or the anterior lenticule surface La of the lenticule L, and to move the focus F along a straight trajectory t that leads onto the spiral shaped work trajectory w to cut the venting channel Ch along the straight trajectory t.

Claim 1:
An ophthalmological device (<NUM>) for surgical treatment of a cornea (<NUM>) of an eye, the ophthalmological device (<NUM>) comprising:
a patient interface (<NUM>), the patient interface (<NUM>) comprising an applanation body (<NUM>) and one or more suction elements configured to fix the applanation body to the cornea (<NUM>) for applanating the cornea (<NUM>) in an applanation zone where the applanation body is in contact with the exterior surface of the cornea (<NUM>);
a laser source (<NUM>) configured to generate a pulsed laser beam (B);
a focusing optical module (<NUM>) configured to make the pulsed laser beam (B) converge onto a focus (F) in the cornea (<NUM>);
a scanner system (<NUM>) configured to move the focus (F) to target locations in the cornea (<NUM>); and
an electronic circuit (<NUM>) configured to control the scanner system (<NUM>) to move the focus (F) to cut inside the cornea (<NUM>) a lenticule (L), the lenticule (L) having a posterior lenticule surface (Lp) and an anterior lenticule surface (La),
characterized in that the electronic circuit (<NUM>) is further configured to control the scanner system (<NUM>) to move the focus (F) to cut in the cornea (<NUM>) a venting channel (Ch, Ch1, Ch2), the venting channel (Ch, Ch1, Ch2) comprising an opening incision (Co, Co1, Co2) in a peripheral area of an exterior surface of the cornea (<NUM>), outside a perimeter (q) of the lenticule (L) from a top view perspective onto the cornea (<NUM>) and outside the applanation zone, and the venting channel (Ch, Ch1, Ch2) connecting fluidically at least one of the posterior lenticule surface (Lp) or the anterior lenticule surface (La) to the opening incision (Co, Co1, Co2), to enable venting of gas produced by cutting the lenticule (L) inside the cornea (<NUM>) through the opening incision (Co, Co1, Co2) to the exterior (<NUM>) of the cornea (<NUM>) outside the applanation zone.