cirugia_refractivaIs an outpatient procedure used to treat nearsightedness, farsightedness and astigmatism. The surgery uses a laser to shape the cornea (the clear, round dome on the front of the eye) to improve the way the eye focuses light rays onto the retina at the back of the eye.

During the LASIK procedure, the ophthalmologist creates a thin layer on the cornea with a microkeratome or a laser beam. The surgeon bends the back layer and accurately removes a specific amount of corneal tissue beneath it, using an excimer laser. The layer is put back in place and heals by itself. In people with myopia, LASIK is used to flatten an abnormally steep cornea. In people with hyperopia, LASIK is used to achieve a steeper cornea. LASIK can correct astigmatism by molding an irregularly shaped cornea, making it smoother and normal.

 

1.LASIK:

lasikLASIK is performed with a surgical instrument called excimer laser in an ambulatory surgery room while the patient is in a recumbent position. First, the eye is numbed with anesthetic drops. A holder is placed between the eyelids to keep them open and prevent the patient from blinking. A suction ring placed on the eye lifts and flattens the cornea and helps keep the eye from moving. The patient may feel the pressure of the holder and the suction ring, similar to the firm pressure of a finger on the eyelid. From the moment the ring is placed until it is removed, vision dims or turns completely black for a few seconds. Once the cornea is flattened, an automatic microsurgery (laser or microkeratome), creates a layer of corneal tissue. The layer is raised and folded back. Subsequently, the excimer laser programmed with measures of the patient’s eye focuses on the eye.

The surgeon makes sure that the laser is in the correct position. The patient faces towards a fixed light or target, while the excimer laser reshapes the cornea tissue. The surgeon then places the layer of corneal tissue to its original position and softens the edges. The corneal tissue layer sticks to the underlying corneal tissue in two to five minutes, and no stitches are required.