Laser Vision Correction

Richard W. Lucius,MD,FACS

LASIK (laser assisted intrastromal keratomeilusis) is the most recent advance in laser vision correction. LASIK uses the precision of the excimer laser to reshape the inside (stroma) of the cornea. This allows for rapid visual improvement and return to normal activities.

The excimer laser is a very precise tool for treating refractive errors. It is so precise that it removes only 0.25 microns (1/4000 mm) of tissue with each pulse. This level of accuracy makes it possible to safely separate individual molecular bonds within the cornea.

The excimer laser has had a good track record since 1987. Approval was obtained in 1996 for the treatment of myopia (nearsightedness). FDA approval has also been granted for the treatment of astigmatism and hyperopia (farsightedness). Since gaining FDA approval, over 8 million people have been made less dependent on glasses or contact lenses by laser vision correction.

Until recently, laser vision correction treated patients based strictly on their optical prescription. In other words, if you were a minus-four nearsighted person, glasses with minus-four lenses would get you back to seeing the best that you could. If you had laser vision correction, that same prescription would be programmed into the excimer laser and the exact amount of tissue would be removed to make a minus-four into a zero. Anyone who was a minus-four would get the exact same treatment. We call this conventional laser vision correction.

Today, with the advent of wavefront diagnostic technology, wavefront guided excimer lasers can now treat patients according to the uniqueness of their entire optical system, not just their prescription.

Most people who choose to have lasik will have both eyes corrected for distance vision. If both eyes are corrected for distance vision and you are at the stage of life where you require reading glasses, you will need to use reading glasses after lasik. Another option is monovision. Monovision is a technique where one eye (usually the dominant eye) is corrected for clear distance vision, and the other eye is corrected for comfortable near vision. Monovision allows a person to see close objects clearly with one eye and distant objects clearly with the other eye. The vision part of the brain tends to filter out the image from the eye that is not in clear focus, so those who have monovision eventually do not pay attention to the eye that is not as clearly focused. Those who have monovision are often able to see well enough both at distance and near to do things at any age without corrective lenses.
Individuals may consider the option of refractive surgery for a variety of personal reasons. While LASIK does not guarantee perfect vision, it holds the promise of reducing one’s dependence on contact lenses or glasses. This may allow many people to more freely pursue their hobbies, sports activities, or career options.

Although millions of people have had their lifestyle enhanced with LASIK, it is not for everyone. You may decide that the potential for glare, halos or other side effects is unacceptable. Even with financing available, you may decide that the cost of wavefront guided LASIK (approximately $2000/eye) is prohibitive.

There are several excellent websites that are good sources of fairly unbiased information. They include; http://www.aao.org/public/ , http://www.fda.gov/cdrh/LASIK/risks.htm, http://www.lasikinstitute.com/ , http://www.medem.com/ , http://www.webmd.com/ , and http://www.nei.nih.gov/ . If you are interested in lasik, a complete eye exam and a thorough discussion with your ophthalmologist will help you determine if LASIK is right for you.