What is it?
Laser vision correction is a procedure, thanks to which a patient can obtain good visual acuity without the need of wearing glasses or contact lenses. A computer-controlled laser beam allows to reshape the superficial layers of the cornea by ablating a thin layer of it. The feasibility to correct the vision errors depends on the thickness of the cornea and its curvature. Surface methods (PRK, Trans PRK, LASEK) enable correction to be made without cutting the cornea, and the procedure is performed only on the surface layer of the tissue. On the contrary, the intrastromal surgery requires making a hinged flap to be made in the superficial portion of the cornea. This flap can be made using microkeratome or femtosecond laser.
What can be treated with laser vision correction?
In our Center, using an excimer laser, we can correct the following vision errors:
- short-sightedness from -1.0 to -8.0 D sph,
- astigmatism with up to 4.5 D of cylinder,
- long-sightedness up to + 4.0 D sph.
Types of lasers
Two types of lasers are used for vision correction:
- Excimer – the gold standard in the field of laser vision correction,
- Femtosecond – initially used for making corneal flap in LASIK / femtoLASIK surgery, nowadays also used for short-sightedness correction (SMILE procedure).
Methods of laser vision correction
PRK procedure is used to correct short-sightedness from -1.0 to -6.0 D and astigmatism of up to 2.5 D
The treatment begins with anaesthesia using anaesthetic eye drops, followed by removal of the corneal epithelium. Then, using a computer-controlled laser beam, superficial layers of the cornea are reshaped. The procedure takes a few minutes and is completely painless. Restoration of the corneal epithelium takes a few days and during this time some discomfort and pain of the eye may occur. To reduce these symptoms immediately after the surgery, the patient wears a contact lens and applies the appropriate drops. Possible complications include clouding of the cornea, which usually disappears after a few months. The incidence of this complication increases depending on the size of the corrected error.
Trans PRK is the newest method of surface vision correction. It is a laser removal of the corneal epithelium combined with the vision correction. During the treatment practically no surgical tools are used. After the surgery, a contact lens acting as a bandage is applied and appropriate medications are administered until the healing process is completed. The cornea heals faster, and there is also less pain discomfort than after the conventional PRK. The treatment requires appropriate software and the use of Schwind Amaris laser. The procedure is not suitable for the correction of small errors of less than 1 D. Possible complications are similar as in the case of the PRK procedure.
LASEK procedure is a method of correcting short-sightedness of up to -8.0 D. The corneal epithelium is not removed, but using a special technique and with the use of alcohol, an epithelial flap is moved away from the place where the laser surgery is performed and repositioned back to its original place after the completion of the surgery. This shortens the recovery time and reduces pain. Additionally, clouding of the cornea is much less common. The treatment itself is a little longer than PRK.
LASIK procedure, being an intrastromal method, is the most complex procedure. It includes cutting a flap of the superficial cornea, reshaping the deeper layers of the cornea, and repositioning of the corneal flap after the procedure on deeper layers is completed. Quick convalescence is the main advantage of this procedure. Possible severe complications such as perforation of the flap during its detachment, torn off flap, epithelium ingrowth underneath the flap, corneal infections that occur more frequently than in the case of other laser treatments, as well as excessive thinning of the cornea with subsequent impairment of its curvature should be included among the disadvantages.
Thanks to cooperation with French company HTM, we offer PRK, TransPRK, LASEK and Wavefront GUIDED LASEK treatments to be performed using the Schwind Amaris 500Hz laser. The HTM company has an international quality certificate ISO 9001: 2000 for the installation and use of the laser.