What is LASIK?
LASIK surgery is a laser procedure designed to reduce or eliminate the need for glasses or contact lenses. First, your surgeon will place a special instrument in your eye. This instrument holds your eyelid open to prevent you from blinking. Following this, you will be asked to focus on a fixation light which is designed to provide a focal point to help control unnecessary eye movement. Next, a small, thin layer of the front of your cornea is lifted using a micro-surgical instrument. This instrument creates a layer, or corneal flap, that stays hinged to the rest of the cornea by one end, or side. This allows the surgeon to lift the corneal flap and begin reshaping the exposed middle layer of the cornea using the Excimer laser. Prior to surgery, the laser’s computer is pre-programmed with your prescribed correction and calculates the proper amount of tissue to be removed (or ablated). Your surgeon will then put the corneal flap back in place. Stitches are not necessary as the flap seals itself naturally.
LASIK and Astigmatism, Farsightedness, and Nearsightedness:
With farsightedness (Hyperopia), the cornea does not “bend” incoming light to the average degree, which causes light to focus behind the normal focal point. This is why farsighted people have blurry vision up close and at a distance. When LASIK is performed to treat farsightedness, the laser gently steepens the surface of the cornea which results in increased bending of incoming light. The focal point will then move closer to the eye’s normal focus point on the front of the retina.
LASIK may also be used as a method of lessening nearsightedness (Myopia); the condition which allows us to have clear vision up close, but not at a distance. LASIK reduces the effects of nearsightedness by gently flattening the cornea with the Excimer laser. In this process, the laser lessens the bending of incoming light and allows it to focus at the normal focal point in the back of the eye.
When astigmatism is present, the cornea is toroidal in shape (like the bowl of a spoon), instead of spherical (like a marble). This causes the image to be “stretched” so that it cannot be focused at one plane. Both near and far vision can be blurred. In this case, LASIK may be used to reshape the cornea to allow for proper focusing. In essence, astigmatism is treated the same way as far- or near-sightedness, but with different amounts of treatment.
Frequently Asked Questions
Am I a Candidate for LASIK?
Is everyone who wears glasses a candidate?
What is the difference between RK and LASIK?
What is the difference between PRK and LASIK?
How long will the procedure actually take?
Is the laser painful?
Can both eyes be done at the same time?
Does insurance cover refractive surgery?
What kind of vision can I expect the day after surgery?
Do the results last?
How much work will I miss?
What are the risks of refractive surgery?