What is Lasik eye surgery?
LASIK stands for Laser-Assisted In Situ Keratomileusis.
LASIK eye surgery is used to correct the vision as it reduces the need for eyeglasses and contact lenses to correct the most common vision problems (e.g., nearsightedness, farsightedness, astigmatism).
The procedure relies on the expertise of a surgeon who’s trained in the ophthalmic surgery.
During the LASIK eye surgery, an ophthalmic surgeon first creates a corneal flap using microkeratome (A microkeratome is a precision surgical instrument with an oscillating blade designed for creating the corneal flap in LASIK or ALK surgery.)
The surgeon then pulls back the flap to expose the underlying corneal tissue, and then the excimer laser ablates (reshapes) the cornea in a unique pre-specified pattern for each patient, which corrects the refractive error. The flap is then gently repositioned onto the underlying cornea without sutures.
Watch this 3D animation on LASIK surgery by AmerraMedical
LASIK surgery is not for everyone. People with severe dry eyes, certain corneal diseases, and other select eye conditions should not undergo LASIK eye surgery.
What is refractive error?
In the human eye, the front surface (cornea) and lens inside the eye form the eye’s “focusing system”.
They are primarily responsible for focusing incoming light rays onto the surface of the retina.
In a perfect system, the power of the cornea and lens are perfectly matched with the length of the eye and images are in focus; any mismatch in this system is called a refractive error, and the result is a blurred image.
What are the primary types of refractive error?
• Myopia (nearsightedness).
• Hyperopia (farsightedness).
• Astigmatism: In people with astigmatism, either the corneal or lens shape is distorted, causing multiple images on the retina. This causes objects at all distances to appear blurry. Many people have a combination of either myopia or hyperopia with astigmatism.
How do glasses or contacts improve vision in people with refractive errors?
Glasses or contact lenses are used to compensate for the eye’s refractive error by bending light rays in a way that complements the eye’s specific refractive error.
In short, LASIK and other forms of refractive surgery correct the eye’s refractive error to reduce the need for other visual aids.
This article is intended for education purpose. If you want professional consultation please visit an ophthalmologist who will examine your eyes.