LASIK Frequently Asked Questions What is LASIK? LASIK, short for Laser Assisted In Situ Keratomileusis, is a surgical procedure that uses a cool (non-thermal) beam of light to gently reshape the cornea — the surface of the eye — to improve vision. The laser removes microscopic bits of tissue to flatten the cornea (for nearsightedness), steepen the cornea (for farsightedness), and/or smooth out corneal irregularities (for astigmatism). In most cases, the thickness of the layer of corneal tissue removed by the laser is less than the thickness of a human hair. The goal of any laser vision correction procedure is to reshape the cornea so it does a better job of focusing images onto the retina. What are myopia, hyperopia and astigmatism? People with myopia, or nearsightedness, have more difficulty seeing distant objects as clearly as near objects. People with hyperopia, or farsightedness, have more difficulty seeing near objects as clearly as distant objects. Astigmatism is a distortion of the image on the retina caused by irregularities in the cornea or lens of the eye. Combinations of myopia and astigmatism or hyperopia and astigmatism are common. How is LASIK different from previous refractive eye surgery techniques? Current FDA approved laser vision correction methods such as LASIK, have a higher predictability of the final result with a lower incidence of complications. Additionally, older non-laser techniques typically involved manually performed incisions rather than automated lasers for correction. Is LASIK right for everyone? Only an eye care professional can determine whether or not an individual is eligible for LASIK treatment. In general, a good LASIK candidate is at least 18 years old, has healthy corneas, and has maintained a stable eye prescription for the last 12 months. Because hormonal levels can affect the shape of the eye, women who are pregnant or nursing should not undergo LASIK treatment. The procedure should also not be performed on patients who:
With collagen vascular, autoimmune or immunodeficiency diseases
Show signs of keratoconus (an eye disorder in which there is thinning of thecornea that results in blurred or distorted images)
Take medications with ocular side effects (such as Accutane® or
Is LASIK safe? The FDA recognizes LASIK as proven, safe and effective. According to guidelines recently released by the Eye Surgery Education Council (ESEC), fewer than 1% of patients who have received LASIK to date have experienced serious, vision- threatening problems. Most LASIK complications can be treated and usually resolve within several months of surgery. There are no known cases of blindness resulting from LASIK. What are the risks associated with LASIK? Although no one knows the exact number of complications, studies suggest that the incidence of minor difficulties such as dry eyes and nighttime glare is around 3% to 5% from combined LASIK and PRK procedures. These minor complications include:
Halos - Some patients will notice glare, halos or starburst around objects inlow-light conditions. For the vast majority, these symptoms are temporary. However, others will continue to experience them for several months orlonger. During pre-operative evaluation, the refractive surgeon candetermine whether or not a person is at high risk for seeing long-term halos.
Dry eyes - There is increased dryness of the eyes typically for several monthsfollowing LASIK, though some patients may experience dryness for a longerperiod of time. It is important to use lubricating drops frequently. If the eyesremain dry for prolonged period, there are other drops or techniques that canhelp. Pre-operative evaluation will help determine whether or not a person isa likely candidate for experiencing dry eyes.
Infection - This is an extremely rare occurrence, with a 1 in 2000-3000
chance (similar to any eye surgery). Fortunately, as the LASIK technique hasdeveloped over the years and proven to be of great benefit to millions ofpatients nationwide, firmly established protocols now exist which minimizethe risk of infection. What happens before LASIK surgery? Before a surgeon will perform LASIK, preoperative tests are performed to screen for glaucoma, cataracts and other disqualifying conditions. The surgeon may also use an instrument called a corneal topographer to photograph and electronically map the eye in order to gather more information about the individual’s eyes prior to treatment.
Because contact lenses change the shape of the cornea, LASIK candidates arerequired to switch to eyeglasses before their baseline evaluation is taken andcontinue wearing only eyeglasses between 2-4 weeks before LASIK surgery. Notleaving contact lenses out long enough for the cornea to assume its natural shapebefore surgery can cause inaccurate measurements and poor vision after surgery.
What happens during the LASIK procedure? Once the surgeon has conducted all pre-operative examinations, the eye is anesthetized with numbing eyedrops, the area around the eye is cleaned, and an instrument called a lid speculum is used to hold the eyelids open. The surgeon will then use a specialized instrument, called a microkeratome, to cut a thin, circular flap - the outermost 20 percent of the thickness of the cornea - to expose the portion beneath. This part of the procedure is called keratectomy.
While the inner cornea (the stroma) exposed, the surgeon will ask the patient tofixate on a specific light source above the patient. This is to ensure that the laserbeam is aligned precisely with the center of the patient’s eye. Once the eye is inthe correct position, the laser treatment is performed. The computer-controlledexcimer laser removes the tissue under the flap and reshapes the cornea of theeye. In less than 60 seconds, ultraviolet light and high-energy pulses from theexcimer laser reshape the internal cornea with accuracy up to 0.25 microns, or1/4000 of a millimeter.
After the pulses of laser energy vaporize the corneal tissue, the flap is put back intoits original position. The surgeon will observe the eye for three to five minutes toensure bonding. Because the cornea bonds quickly, healing is rapid, and the eyedoes not require stitches. Is LASIK painful? The procedure is painless, however, most people experience 4-6 hours of mild irritation after their LASIK procedure. How long does the procedure take? The laser treatment on the ALLEGRETTO WAVE usually takes less than thirty seconds, while the entire procedure takes around 10-15 minutes per eye. How long must people wait to resume normal activities after a LASIK treatment? In most cases, people can return to work within 1-3 days following LASIK surgery. Excluding the day of surgery itself, people may begin driving as soon as they see well enough. Women can start wearing makeup within two to three days of treatment, however, they are advised to wear only new cosmetics in order to decrease risk of infection. Will a person’s vision remain stable long after the procedure? The vision correction is permanent. However, a person’s vision may change
naturally with time and LASIK does not affect visual conditions that may developwith age. Also, LASIK does not prevent presbyopia and the eventual need forreading glasses. Depending on the cause, retreatment may be a viable solution tolater vision changes, and other treatment options also exist. Where can I get more information? For more information, visit us at www.carolinaeye.com or contact our patient services counselor by phone at 910.295.1501 or 800.733.9355, or by email at [email protected].
If at any time you need to reach our main center, please call 910.295.2100 or800.733.5357. Information obtained from Allegretto Wavelight
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