Correcting Vision With Refractive Eye Surgery
Vision problems are common, including difficulty seeing objects close up or far away—or both. It used to be that glasses or contact lenses were the only option. Today, eye surgery has the potential to permanently correct vision without the use of these visual aids.
How the Eye Works
When you look at an object, the light the object reflects is bent or refracted through the cornea—the clear layer that forms the front window of the eye—and then through the lens, to land on the retina. The nerve endings in the retina send signals through the optic nerve to the brain, where the image is recognized.
The most common eye problems result from refractive errors caused by imprecisely focused light waves. This can be due to a misshaped eyeball, cornea, or lens. The four basic types or errors are:
Making light rays focus on the retina properly will reduce refractive error. Traditionally, glasses and contact lenses correct the error and enhance vision. Today, more and more people are opting for refractive surgery. By changing the shape of the cornea, which is responsible for most of the eye's focusing power, refractive surgery can decrease or eliminate dependency on glasses or contact lenses. It cannot, however, improve vision beyond what glasses or contacts were able to accomplish. Below are the most common types of refractive surgery.
Photorefractive Keratectomy (PRK)
PRK reduces refractive error by sculpting the surface of the cornea using a laser. It is recommended for people with:
It will take a couple of days for the epithelium to regrow over the cornea. For the first few weeks, your vision may fluctuate between clear and blurry. Functional vision returns in six weeks, and vision stabilizes over the next six months.
Laser-Assisted in situ Keratomileusis (LASIK)
LASIK uses the same laser as PRK, but adds an additional step that allows the treatment of more significant refractive errors with less postoperative pain and faster visual recovery. For this reason, it has become the most widely performed of the refractive surgeries. It is recommended for people with:
Removing the tissue on the inside of the cornea changes its shape, which reduces the refractive error.
It can take up to three to six months to for your vision to stabilize. The related procedure termed “LASEK” is also used by many ophthalmologists and is probably similar in terms of postoperative recovery and outcome.
Other procedures that are being used more commonly include:
If you are considering refractive surgery, be sure that your surgeon explains all possibilities to you and gives you a convincing reason why the proposed procedure is best for you.
Making the Decision
As with any medical procedure, there are risks involved with refractive surgery. Some risks and possible complications include:
Not all people with refractive errors are good candidates for refractive surgery. Talk with your doctor to determine what line of treatment is right for you.
American Academy of Ophthalmology
American College of Eye Surgeons
Alternative refractive surgery procedures. EyeSmart website. Available at: http://www.geteyes.... Accessed August 15, 2012.
Candidacy for procedures. International Society of Refractive Surgery website. Available at: http://www.aao.org/isrs/patients/ref_candidacy.cfm. Accessed August 15, 2012.
LASIK—laser eye surgery. EyeSmart website. Available at: http://www.geteyes.... Accessed August 15, 2012.
Photorefractive keratectomy (PRK) eye surgery. ClevelandClinic.org website. Available at: http://www.clevela.... Accessed August 15, 2012.
What is refractive surgery? EyeSmart website. Available at: http://www.geteyes.... Accessed August 15, 2012.
Last reviewed August 2012 by Brian Randall, MD