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Femtosecond laser LASIK flap preparation with conical incision and positional spikes
Jost B Jonas1, Urs Vossmerbaeumer
1Department of Ophthalmology, Faculty of Clinical Medicine Mannheim, University of Heidelberg, Mannheim, Germany. Jost.Jonas@augen.ma.uni-heidelberg.de
Purpose:
To describe the creation of corneal flaps for laser in situ keratomileusis (LASIK) with conical incisions and positional spikes that may increase postoperative rotational flap stability.
Setting:
University Eye Department.
Methods:
A corneal flap was prepared in 5 freshly enucleated porcine eyes using a femtosecond laser. In the first step, the flap bed with a diameter of 8.0 mm was created by an intrastromal incision running parallel to the corneal surface. In the second step, a posterior-anterior incision was created with a diameter of 8.0 mm at the level of the first incision and 7.0 mm at the corneal surface. In addition, a hinge and 3 spikes were prepared in the flap with corresponding notches in the surrounding tissue.
Results:
In all eyes, the corneal flaps were prepared easily within 5 minutes.
Conclusion:
Femtosecond laser technology allowed a new type of LASIK flap formation with conical incisions and positional spikes.
