Why the Procedure Is Performed
LASIK is done most often on people who use glasses or contact lenses because of myopia (nearsightedness). It is occasionally used to correct farsightedness. It may also correct astigmatism.
The FDA has approved the Excimer Laser to correct nearsightedness up to -12.00D with -4.00D of astigmatism, and farsightedness from +1.00 to +6.00 with 1.00D of astigmatism. (Diopter, symbol D, is the measurement of the refractive error. A negative D value indicates nearsightedness and a positive D value indicates farsightedness.)
The FDA, in cooperation with the American Academy of Ophthalmology, has developed the following guidelines and recommendations for good candidates for LASIK:
* You should be at least 18 years old (21 for some lasers), since the vision of people younger than 18 usually continues to change. An exception is the small child with one very nearsighted and one normal eye. The use of LASIK to correct the very nearsighted eye may prevent amblyopia (lazy eye).
* You should not be pregnant or nursing because these conditions might change the measured refraction of the eye.
* You should not be taking certain prescription drugs, such as Accutane or oral prednisone.
* Your eyes must be healthy and your prescription stable. If you're myopic, you should postpone LASIK until your refraction has stabilized, because myopia may continue to increase in some patients until their mid to late 20s.
* You should be in good general health. LASIK may not be recommended for patients with diabetes, rheumatoid arthritis, lupus, glaucoma, herpes infections of the eye, or cataracts. You should discuss this with your surgeon.
* Weigh the risks and rewards. If you're happy wearing contacts or glasses, you may want to forego the surgery.
* Understand your expectations from the surgery. Are they realistic?
* For patients with presbyopia, LASIK cannot correct so that one eye can see at BOTH distance and near. However, LASIK can be used to correct one eye for distance and the other for near. If you can adjust to this correction, it may eliminate or reduce your need for reading glasses. In some instances, surgery on only one eye is required. If your doctor thinks you're a candidate, ask about the pros and cons.