Lasik Surgery Explained

Watch Lasik Expert Rajesh Khanna MD talk LIVE about what is Lasik Eye Surgery and if it can correct your vision!


Lasik is a type of eye surgery in which an extremely precise laser is used to modify the corneal surface so as to remove irregularities that have impaired your vision. The cornea is the front part of the eyeball, the white part around the iris. Lasik eye surgery corrects: Near-sightedness (myopia) Far-sightedness (hyperopia) Astigmatism. It does not correct presbyopia, which causes the need for reading glasses that overtakes all of us once we reach the age range of 40-50. Presbyopia treatments must deal with the stiffening lens and weakening eye muscles rather than just modifying the corneal surface.

lasik flap

How Lasik Works

Lasik stands for Laser In-situ Keratomileusis, a procedure designed “to shape the cornea from within.” During Lasik surgery, this is exactly what happens: your cornea is re-shaped using a state-of-the-art Excimer laser. The laser vaporizes tiny amounts of corneal tissue such that the cornea is made less steep. Then the light rays will focus on your retina and you’ll be able to see clearly. This improves your eyes’ ability to focus, providing you with clear vision. Lasik eye surgery is done to enhance the natural vision and gain freedom from glasses and contact lenses. The eye cannot be made longer or shorter. We therefore alter the focusing power of the eye. As with a camera where we can add or remove lenses to get a good picture. Lasers achieve this feature by changing the shape of the clear front part of the eye called the cornea. Before Lasik is performed, every microscopic irregularity that is affecting your vision will be mapped out using an advanced technology called Wavefront Diagnosis. This “map” of your eyes will then be used to guide the Excimer laser in re-shaping your cornea, helping it target and correct each irregularity. The result is clear, unhindered vision that does not require dependence on glasses or contact lenses.

Correcting Myopia with Lasik Eye Surgery

Glasses and/or contact lenses are the most common treatment method for myopia. However, Lasik can permanently correct your myopia, granting you the crystal clear vision you’ve always wanted without the need for eyewear. It is by far one of the most popular refractive surgeries performed. This incredibly effective refractive surgery procedure works by changing the shape of your cornea, allowing light to properly focus on the surface of your retina.

Correcting Hyperopia with Lasik Eye Surgery

In hyperopic vision the cornea is too flat. So the light rays are refracted too little and come to a focus behind the retina. So again we see a blurry image. Most people with hyperopia do not need treatment until later in life. When you are young, your eyes are usually able to adjust to compensate for farsightedness. However, people with more pronounced hyperopia may benefit from glasses and contact lenses to relieve the amount of stress on their eyes. Lasik eye surgery is capable of treating a wide range of hyperopia cases with excellent results. This incredibly effective refractive surgery procedure works by changing the shape of your cornea, allowing light to properly focus on the surface of your retina. However, some people may not be perfect candidates for Lasik. With hyperopia an innovative SUPERLASIK technique may be used instead of Lasik to make vision correction possible for a wider range of myopia patients.

Correcting Astigmatism with Lasik Eye Surgery

Astigmatism consists of small irregularities on the corneal surface such that vision is uneven and has blurry areas. While glasses and contacts are an effective treatment method for astigmatism, they can be limiting, especially if you have an active lifestyle. Many people with severe cases of astigmatism can completely transform their vision through Lasik eye surgery. If you have an astigmatism, Lasik works by treating the source of your astigmatism: the shape of your cornea. With targeted laser energy the surgeon will precisely alter the shape and curvature of your cornea, allowing light to focus properly for the first time. Most astigmatism patients are excellent Lasik candidates. However, your eyes may have certain characteristics that would prevent you from having a successful outcome with Lasik. If this is the case a doctor may recommend PRK (Photorefractive Keratectomy) as an alternatives.

By Dr. Rajesh Khanna, MD