Ophthalmologic laser device and method for preventing and treating aftercataract
An ophthalmologic laser device includes a pulsed laser configured to produce radiation focused along at treatment beam path. A variably adjustable beam deflector unit and a focusing lens system are disposed in the treatment beam path. The deflector unit is configured to focus the radiation in different target volumes. Measuring equipment is configured to determine a shape and position of optical interfaces along a detection beam path. A control unit is configured to control the laser and the deflector unit and to implement steps including determining a shape and position of an interface of a membrane of a capsular bag of an eye located in a treatment area using the measuring equipment, determining coordinates of a target volume such that, on irradiation of the target volume, a pressure wave runs from the target volume to the anterior or posterior membrane, and adjusting the deflector unit to the target determined volume.
1. An ophthalmologic laser device comprising:
a pulsed laser configured to produce treatment laser pulses of a predetermined pulse energy that propagate along a treatment beam path;
a focusing lens system disposed in the treatment beam path;
a variably adjustable beam deflector unit disposed in the treatment beam path and configured to deflect the treatment laser pulses to different volumes;
a measuring equipment configured to determine a shape and position of optical interfaces along a detection beam path; and
a controller configured to control the pulsed laser and the variably adjustable beam deflector unit, the controller being configured to:
determine, using the measuring equipment, a shape and position of at least one interface of a membrane of a capsular bag of an eye located in a treatment area,
determine, based on the predetermined pulse energy, an effect distance over which a hypothetical pressure wave, which would be induced by irradiation of tissue in an interior space of the capsular bag of the eye with a laser pulse of the predetermined pulse energy, must propagate before an intensity of the hypothetical pressure wave has decreased to a level insufficient to tear the membrane of the capsular bag of the eye but sufficient to cause a photodisruption-free, non-linear interaction with the membrane that detaches cells or molecules from the membrane or deactivates the cells or molecules,
determine, as a function of the effect distance, coordinates of a center of a target volume, the center of the target volume being located at the effect distance from the at least one interface of the membrane of the capsular bag of the eye, and
adjust the deflector unit so as to deflect the treatment laser pulses produced by the pulsed lasr to the target volume.
2. The laser device according to claim 1 , wherein the control unit determines the coordinates of the center of the target volume such that the target volume lies completely in an interior space of the capsular bag.
3. The laser device according to claim 1 , wherein the effect distance is determined using at least one of a sample calculation or a look-up table.
4. The laser device according to claim 1 , further comprising a fixing device for releasable fixing of a position of the eye relative to the focusing lens system,
wherein the control unit is further configured to fix, using the fixing device, the eye before determining the shape and position of the at least one interface of the membrane of the capsular bag of the eye, and
wherein the control unit is further configured to release the eye after deflecting the treatment laser pulses produced by the pulsed laser to the target volume.
5. The laser device according to claim 4 , wherein the control unit is further configured to, after the fixing the eye and before releasing the eye, at least one of the following additional incisions using the pulsed laser or an additional laser:
capsulorhexis incisions in an anterior capsular bag membrane,
fragmentation incisions in a lens of the eye,
corneal access incisions, and
limbal relaxing incisions.
6. The laser device according to claim 1 , wherein the treatment beam path runs as a free beam through a cornea of the eye and a pupil of the eye.
7. The laser device according to claim 1 , comprising an ultra-short pulse laser and a short pulse laser, wherein the beams of these two lasers run partially coaxially in the treatment beam path.
8. The laser device according to claim 1 , wherein the device is switchable between an emission with image-recording radiation output and an emission with treatment radiation output, and wherein the control unit is configured to implement:
adjustment of the emission with image-recording radiation output for determination of the shape and position of the at least one interface, and
adjustment of the emission with treatment radiation output for irradiation of the target volume or several target volumes.