By David Ivanov, Biochemistry and Molecular Biology, 2015
LASIK, or laser-assisted in situ keratomileusis, is a surgical procedure commonly used to correct for visual defects or lack of visual clarity. Commonly referred to as laser eye surgery, LASIK is a type of surgery that is used to alleviate visual loss associated with common defects of the eye, such as myopia (nearsightedness), hypermetropia (farsightedness), and astigmatism. Astigmatism, like near and far-sightedness, can be caused by the irregularity in shape of the cornea that leads to blurred vision. For all three cases, corneal remodeling via LASIK can be performed (Thomson, 2015).
The cornea is the outermost layer of the eye, the transparent part that one can touch, and upon which contact lenses are placed. It is responsible for most of the focusing power, and thus is a common culprit in visual defects of the eye. The cornea focuses the light reflected into the eye, through the lens and onto the the retina at the back of the eye, which senses light and converts it to nerve impulses, and transmits the resulting image to the brain for processing. This then produces the image that we ‘see’. While the retina is the part of the eye that is light-sensitive and is responsible for transmitting the image to the brain, the cornea, along with the lens, must focus light reflecting off of three dimensional surfaces so that they strike onto the anterior, or front part of the retina. Without this precise focusing of light rays directly onto the retina, the brain generates a blurred image (NKCF 2014).