Extracting lenticules for refractive correction
In certain embodiments, refractive correction includes controlling a focus of pulsed laser radiation having ultrashort pulses. A channel is created with the pulsed laser radiation to facilitate separation of the lenticule from the eye. A posterior incision is created with the pulsed laser radiation to form a posterior side of the lenticule. An anterior incision is created with the pulsed laser radiation to form an anterior side of the lenticule.
1. A method for refractive correction, the method comprising:
controlling, by one or more controllable components of a laser device, a focus of pulsed laser radiation to create a lenticule in an eye, the pulsed laser radiation having a plurality of ultrashort pulses;
creating a straight posterior channel having a length between 1 to 5 millimeters with the pulsed laser radiation;
creating a posterior incision with the pulsed laser radiation to form a posterior side of the lenticule, the posterior channel substantially tangential to the posterior incision to facilitate separation of the posterior side of the lenticule from the eye;
creating a straight anterior channel having a length between 1 to 5 millimeters with the pulsed laser radiation;
creating an anterior incision with the pulsed laser radiation to form an anterior side of a lenticule, the anterior channel substantially tangential to the anterior incision to facilitate separation of the anterior side of the lenticule from the eye, the anterior channel disconnected from the posterior side of the lenticule, the posterior channel disconnected from the anterior side of the lenticle;
creating the anterior incision and the posterior incision yielding a refractive profile for refractive correction; and
creating one of the anterior channel or the posterior channel with the same width at each end and create the other of the anterior channel or the posterior channel with different widths at each end.
2. The method of claim 1 , creating the posterior channel further comprising:
creating the posterior channel that has the same width at each end.
3. The method of claim 1 , creating the anterior channel further comprising:
creating the anterior channel that has different widths at each end.
4. The method of claim 1 , further comprising:
creating a removal incision with the pulsed laser radiation to facilitate removal of the lenticule from the eye.
5. The method of claim 1 , the channel having an angle with respect to a surface of the eye that is between zero and 20 degrees.
6. The method of claim 1 , an ultrashort pulse having a pulse that is less than one (1) nanosecond.
7. The method of claim 1 , further comprising:
controlling, by the one or more controllable components, the focus of pulsed laser radiation to have a focus volume with a diameter of 5 micrometers or less.
8. The method of claim 1 , further comprising:
generating, by the laser device, the pulsed laser radiation with a wavelength of 300 to 650 nanometers.
9. The method of claim 1 , further comprising:
executing a zigzag scan pattern to create the posterior incision.
10. The method of claim 1 , further comprising:
executing a spiral scan pattern to create the posterior incision.
11. The method of claim 1 , further comprising:
creating the lenticule with a diameter of 6.5 millimeters.
12. The method of claim 1 , further comprising:
creating the lenticule with a thickness of 50 micrometers.
13. The method of claim 1 , further comprising:
creating the anterior channel with a narrower width towards the entrance of the channel and a wider width towards the center of the lenticule.
14. The method of claim 4 , further comprising:
creating the removal incision with a length in a range of a diameter of the lenticule plus or minus 2 millimeters.