Lasik is the type of corrective eye surgery for vision correction performed with the use of laser. There are two types of surgery: Lasik and PRK. Lasik is just one type of laser eye surgery.
The term LASIK stands for Laser-Assisted-in-Situ Keratomileusis, and represents an effective surgical vision correction for individuals with refractive errors such as myopia (nearsightedness), hyperopia (farsightedness), as well as astigmatism.
How Does Lasik Work?
The Lasik procedure is designed to reduce or correct these refractive errors by permanently remodeling the shape of the cornea (the clear covering of the front of the eye) under the flap with the laser.
The procedure combines the use of microkeratome – a surgical instrument used to create a thin flap on the eye and the excimer laser to remove thin layers of cornea. When the cornea is reshaped, the eye’s focusing power is increased and the individual’s visual acuity is enhanced.
The standard lasik eye surgery procedure includes:
- The eye is numbed with anesthetic drops.
- A corneal suction ring is applied to the eye, holding the eye in place to prevent blinking.
- The patient is asked to fixate their eyes on a designated light while the surgeon creates a flap in the cornea with the help of the blade device called microkeratome. A hinge is left at one end of this flap
- A computer-controlled laser light (which was previously programed based on the correction required by the refractive error) is applied to the inner layers of the cornea reshaping it.
- Once the laser has reshaped the cornea, the surgeon gently replaces the flap to the original position allowing the eye to heal itself naturally.
When lasik procedure is performed, the cornea surface will be reshaped based on the eye’s refractive error that requires correction.
- For those with hyperopia (farsightedness) – where the cornea is not round, which causes the light to focus behind the normal focal point, the laser beam will steepen the surface of the cornea causing the eye’s focus point to be moved closer to the normal focus point for creating a clearer image.
- For those with myopia (nearsightedness) – where the cornea is too steep causing the images to focus in front of the normal focus point, the laser beam will flatten the surface of the cornea allowing the light to focus at the normal focus point in the back of the eye.
- For those with astigmatism – where the cornea is curved irregularly impending the light to focus properly on the retina, the cornea is being reshaped in order to allow the eye to focus properly.