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Vision Correction with LASIK
LASIK was first performed in the early 1990s in Greece, but the two main components of the surgery were performed separately long before then. South American surgeons began developing corrective procedures in the 1960s by removing a portion of corneal tissue, reshaping it, and then placing it back on the eye. Excimer laser correction has been done on the surface of eyes since 1987. Combining the advanced forms of both types of technology gives LASIK certain advantages for correcting vision. For the procedure, the patient sits in a surgical chair which reclines into a horizontal position. A surgical assistant instills topical anesthetic drops to numb the eye for a painless correction. Assistants then carefully drape the patient's face around the eye to ensure a perfectly clean surrounding area for the surgery. During LASIK surgery, a flap is created in the outer layers of the cornea, using either the IntraLase FS laser or a microsurgical instrument called a microkeratome. The flap is then lifted and pulled back so the excimer laser can treat only the middle layer of the cornea. Traditionally, the instrument used for creating a flap has been the microkeratome. It cuts and lifts a flap that is approximately 1/4 to 1/3 of the corneal thickness. This circular flap remains attached to the cornea by a small hinge of tissue. The hinge enables the flap to be lifted away from the central cornea. The excimer laser can then be used to reshape the exposed mid-layer of the cornea. In recent years, the IntraLase Wavefront laser has become available to create a flap using multiple short pulses. These pulses are so close together they create an almost complete separation of the flap from the rest of the cornea, but they do not actually lift the flap. If the flap pattern is judged to be complete and satisfactory, a delicate separation of the flap is performed with a few gentle manipulations using a surgical instrument. Wave front - Custom LASIKRecent media coverage of wavefront-guided Custom LASIK has drawn widespread attention to this new development in laser vision correction surgery. Since the excimer laser was approved as safe and effective in 1995, several million Americans have had their vision corrected and have recommended LASIK to friends and family. However, concerns about nighttime glare, and reports of a very small percentage of problems have caused many people who would prefer not to wear glasses or contacts to put off having LASIK surgery. Contrary to the notion that "...the laser does all the work in LASIK," the addition of advanced wavefront technology used in Custom LASIK requires even more surgical expertise and judgment than conventional LASIK. Based on clinical research submitted to the FDA, most eye doctors feel that Custom LASIK will enable more people to have their vision corrected more safely than ever before. In fact, many patients who had wavefront-guided Custom LASIK found their night vision after surgery was better than their night vision with glasses or contacts before surgery. This is not to say that LASIK, as it's been performed since 1996, is not a safe procedure. On the contrary, our practice has performed thousands of LASIK procedures with overwhelmingly good results. Custom LASIK is expected to provide an extra measure of precision that will allow many patients who've been "waiting for better technology" to now feel comfortable having their vision corrected. Conventional LASIK is based upon the patient's eyeglass prescription. Custom LASIK takes into account not just the eyeglass prescription but also subtle irregularities in the way each individual's eye focuses light. Two people can have the same eyeglass prescription, but no two people have the same wavefront map. In other words, with Custom LASIK more sophisticated measurements are used and a more precise correction is obtained. Some Custom LASIK patients even achieve better than 20/20 vision! Not all LASIK patients will benefit from custom cornea ablation. Custom LASIK is most valuable for those people with greater than average irregularities in their prescription. Only a doctor experienced in LASIK can determine the value of Custom LASIK for each individual person. Contrary to the old myth that "the laser does all the work in LASIK", adding the more advanced technology of wavefront analysis requires even more surgical expertise and judgment than conventional LASIK. Now that Custom LASIK is a reality, many patients - who were told they could not have their vision corrected in the past because of large pupils or unusual prescriptions - may now safely reduce or eliminate their need for glasses or contacts. The LASIK ProcedureBefore the LASIK procedure, your eyes will be anesthetized with eye drops and a speculum will be used to restrict eyelid movement. You will be instructed to fixate on a flashing red light with one eye, while the other eye is taped shut. To perform LASIK, the surgeon first creates a flap of tissue on the surface of the eye. During these few seconds, you may feel some slight pressure, but no pain, and your vision will go dim.
For each eye, the laser application time is usually less than one minute and the whole LASIK procedure around 15 minutes. After the LASIK ProcedureImmediately after the LASIK procedure, your vision will still be quite blurry. It is common for one eye to be less comfortable than the other for the first few weeks and for one eye to see faster than the other. This is normal. It takes several weeks and often a few months for your vision to improve and stabilize. In the first week or two, most people feel as though they're looking through Vaseline, fog, or a dirty contact lens. Often they can see objects but the contrast or sharpness and clarity have not yet returned. This is completely normal. It usually takes a few weeks for this to start really coming back well and by three months, most peoples' eyes and eye prescriptions have stabilized. It's also common for your vision to fluctuate from moment to moment or day to day during this period. Even though your eyes don't feel particularly dry, please use the artificial tears we provided in your kit or other similar tears from the pharmacy several times a day or as needed for the next few weeks. Avoid those with preservatives and consult your post-op information sheet for the brands we recommend. It is critically important not to rub your eyes or get hit in the eye, especially during the first few weeks after LASIK. This is similar to any surgical procedure in that one should protect the area as it heals. Most people can start exercising within about a week but swimming is not advised until after two weeks. Check with the eye doctor who examines you after LASIK surgery to see when you can return to your normal activities. At your first and second visit after surgery your eye doctor will also tell you whether you need temporary glasses to improve your vision while your eyes are healing. This is not uncommon and generally does not suggest a problem. Red spots on the white of your eye are perfectly normal and those will usually fade over two weeks or so. Complications after LASIK surgery by expert surgeons are uncommon. There are a few symptoms that may indicate that there may be something that needs your doctor's attention. These include: discomfort that is getting worse, rather than better in the first week or so following surgery, a significant reduction in your vision and not just a mild fluctuation, a lot of discharge or redness or swelling of your lids. The Risks of LASIKLASIK correction is a very safe procedure. When complications do arise, they can generally be effectively treated with further surgery. As with any surgical procedure, there are risks involved with LASIK. Side effects may include overcorrection or undercorrection, excessively dry eyes, corneal scarring, corneal edema, infection, persistent eye pain or discomfort, inability to wear contact lenses, glare and halos in the line of vision, and a decreased ability to see well at night or in fog. However, most of these subside as the healing progresses after LASIK surgery. The chance of having a serious vision-threatening complication from LASIK is less than 1%. To our knowledge, there have been no reported cases of blindness in the United States from LASIK. The low incidence of complications listed here reflects the exclusive Digby Eye Associates experience: * Infection (less than 1/5,000) * Difficulty Creating a Flap (1%) While Digby Eye Associates has had excellent results and an enviable safety record with microkeratome LASIK, we now consider IntraLase LASIK to be our preferred method. * Safety: Because microkeratome LASIK completely cuts and lifts the flap, if an irregularity occurs, the surgeon has no choice but to deal with the irregularity immediately. However, with IntraLase, since the flap is not separated completely and not lifted immediately, the character and quality of the flap can be judged first. If deemed unsatisfactory, the flap pattern can be left untouched and the IntraLase pattern can be repeated later. * Haze and Irregular Astigmatism (less than 2%) * Epithelial Growth Under the Flap (less than 1%) * Shifting or Wrinkling of the Flap (less than 1%) * Interface Inflammation (less than 1%) The Benefit of LASIKAccording to the Eye Surgery Education Council (ESEC), more than 90 percent of patients who undergo LASIK experience vision improved to 20/40--the minimum vision standard for driving an automobile or playing sports without corrective eyewear. Fifty-six percent of patients report post-surgery 20/20 vision. Although LASIK will not prevent age-related eye conditions or diseases, results are permanent. Most patients return to their normal daily activities one day after surgery. The results for Custom LASIK with wavefront technology are even more impressive. Custom LASIK postoperative results are more predictable and unprecedented, with over 20% of patients achieving 20/12.5 vision or better, over 70% of patients achieving 20/16 or better and, 98% of patients achieving 20/20 or better without lenses after surgery. This result has been referred to as "super vision" -- significantly better than 20/20. The incidence of postoperative complications such as glare, halos, and difficulties with night vision that occur for a small minority of LASIK patients can also be significantly reduced with wavefront technology. LASIK FAQ'sIs LASIK right for me? The LASIK procedure allows for correction of low to extreme degrees of myopia, up to -14 diopters or greater, and low to moderate degrees of hyperopia and astigmatism, up to 6 diopters. Because of its many advantages, LASIK is our procedure of choice in most cases, even for lower prescriptions. After a thorough eye examination, your eye doctor can tell you whether or not you are a good candidate for LASIK. Whether laser vision correction is right for you depends on a number of medical considerations. It also depends on you, your lifestyle and your expectations. Speaking with someone who has had LASIK, as well as your eye doctor, can help you make the right decision. If you would like to talk with someone who has been through the process, please call our office in Greensboro at 336-230-1010 for a contact list of previous LASIK patients who have offered to share their experiences with you. Assuming your eye doctor determines that you area good candidate for laser vision correction, the decision to have LASIK surgery is ultimately yours. Only you know what impact wearing glasses and/or contact lenses has had on the quality of your life, and only you know the value to you of reducing your dependency on these visual aids. My eyes are very sensitive and I have difficulty tolerating anything near my eye, how can I have LASIK? Most people choose to take an oral sedative for relaxation. A gentle lid holder is used to prevent blinking. A light inside the laser provides a target to focus on during the entire procedure. Even the most sensitive patients are able to have LASIK. Are both eyes done at once? Yes, unless a patient specifically chooses to have one eye done at a time. Most patients want to have their vision corrected with minimum travel and healing time, and performing both eyes at once normally yields the most rapid visual recovery. How long does the procedure take? The entire procedure takes ten to fifteen minutes to complete for both eyes. The actual laser exposure time is typically less than 30 seconds per eye. When can I go back to work? Depending on your occupation, some patients may return to work within 24-48 hours. When will I be able to see after the procedure? Typically, patients are able to see immediately after the procedure, however vision will be foggy for the first several hours. Vision will normally improve for the first 24 hours and most, but not all, patients are able to drive the first morning after their procedure. How long will it take for my vision to gain maximum improvement? Nearly all patients have recovered vision enough to work and resume all normal activities within 48 to 96 hours. The quality of your vision will usually improve over a period of weeks and months. Am I going to get 20/20 vision? A high percentage of patients achieve 20/20 vision from LASIK, and nearly all patients achieve 20/40 vision, the level of vision needed to drive without correction. Patients who expect to have 20/20 vision from the procedure and who would be unhappy with anything less are best advised not to have LASIK. No one can guarantee a 20/20 result. How much pain will there be after the procedure? After the anesthetic drops wear off, patients usually describe approximately 6 to 12 hours of mild discomfort, scratchiness, watering, light sensitivity, and a sensation of something in their eyes. It is rare for a patient to need anything more than a mild over-the-counter pain reliever, and many patients need nothing at all. The procedure itself heals very quickly with any discomfort leaving in nearly all patients by 48 hours. Is the procedure permanent? If your prescription is stable, it is believed that the results of your procedure will be permanent. The very first patient who had Laser Vision Correction approximately 10 years ago is reported to still have 20/20 vision. Are there possible complications? As with any medical procedure, there are risks and complications that may occur in LASIK. Serious sight threatening complications are rare. Every patient will receive an extensive informed consent before they receive LASIK. Will reading glasses be needed after the procedure? If reading glasses are not required before the procedure, a full correction with LASIK will not cause you to wear them. However, as a result of the normal aging process of the eye, reading glasses are normally needed by age 45. If you currently wear bifocal glasses or reading glasses over your contacts, you may be a candidate for Monovision, which leaves one eye slightly nearsighted so that reading glasses may not be required. What activity restrictions are there after the procedure? Patients should not able to rub their eyes or swim underwater for two weeks after the procedure. Normal activities may be resumed the first day after the procedure including golf, tennis, or other exercise.
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Laser In Situ Keratomileusis (LASIK) is a laser surgical procedure effective for correcting all ranges of nearsightedness, farsightedness and astigmatism, except extremely high degrees. The most commonly performed vision correction procedure, LASIK is performed on nearly 1 million patients per year. LASIK combines corneal flap surgery with excimer laser reshaping for dramatic results and rapid visual recovery.
The surgeon then positions the patient's eye under the excimer laser which is programmed to remove microscopic layers of tissue from the internal part of the cornea, called the stroma, under the flap. The cool laser beam vaporizes tissue away, one microscopic layer at a time, without burning or cutting. This tissue does not replace itself after it is removed. Since the excimer laser light is created at a specified wavelength that does not pass through the cornea, no other part of the eye is affected.
To correct nearsightedness, the laser removes central tissue to decrease the curvature, allowing light rays to focus farther back in the eye to reach the retina. 
To correct farsightedness, the laser removes small portions of peripheral tissue to increase the curvature so light can focus within a shorter distance. 
To correct astigmatism, the laser removes tissue in designated areas to equalize the curvatures of the cornea.
After the tissue has been removed, the surgeon places the flap back in its original position where it heals into place with no stitches. The cornea has amazing natural bonding qualities. Within a few minutes, the flap adheres to the underlying tissue. The edges of the flap heal over in 12 to 48 hours, with the entire flap gaining adhesive strength as it continues to heal in the following weeks and months.