IN THIS ARTICLE: Introduction Figure 1-Anatomy of the Eye What Are Your Options? LASIK Figure 2-The LASIK Surgery Process LASEK and Epi-LASIK PRK LTK Are You a Suitable Candidate? How Well Does It Work? What Can Go Wrong? How Do You Find a Surgeon? What to Expect After LASIK Surgery

Return to My Personal Member Homepage Introduction  They put drops in your eye to numb it, pull back and hold your eyelid so you won’t blink, place suction cups on your eyeball to keep it from moving, take a small scalpel and slice off a thin layer of your eye, and then aim a laser at it and zap away. No, this isn’t a gruesome scene from a horror flick, it’s laser eye surgery...and millions have signed up—and paid thousands of dollars—for the privilege.  If you are nearsighted, farsighted, or have astigmatism—and if you can cope with the potential “yuck” factor of the procedure—then laser eye surgery likely can correct your vision for good. If you’re considering surgery, you should first do a little research to learn about the different types of procedures, the chances of a successful correction, the risks of complications, which physician to use, and costs. This article should help you get started.  Figure 1-Anatomy of the Eye  What Are Your Options?  LASIK surgery has become by far the most common laser vision surgical method, but there are several other options. All of the laser methods seek to accomplish the same goal: to reshape the cornea, which is a curved, transparent covering at the front of the eyeball. The cornea provides up to 70 percent of an eye’s focusing power, focusing incoming light onto the retina at the back of the eye, much like the lens of a film camera focuses light on film. If the cornea is not shaped properly relative to the length of the eyeball, light will not focus properly and you will be nearsighted, farsighted, or have astigmatism. Although all of the laser eye surgery options try to change the shape of the cornea so that light is optimally focused onto the retina, there are slight differences in how the surgeries are performed. Below, we describe the most common types of procedures and the pros and cons of each.  LASIK  During LASIK (laser in-situ keratomileusis) surgery, the patient’s eye is anesthetized with eye drops. The eye that is not being treated is usually temporarily taped shut. Then a device is attached to restrict eyelid movement. The patient is then told to hold his or her gaze on a small light, straight ahead.  The surgeon will begin by using a special surgical blade or cutting laser to create a thin flap of corneal tissue that is then lifted away from the surface of the cornea while still hinged at one end. During this process, the eye will be held in place by a suction ring, which is usually removed after the flap is cut.  Next, the surgeon applies a laser to the corneal tissue that is now exposed beneath the lifted flap. The laser removes tiny amounts of corneal tissue, thus reshaping the surface into the desired contour. During this shaping process, the laser is guided by information that has been programmed into its controlling mechanism by the surgeon—information about your unique prescription and other eye specifications.  When the reshaping is complete, the surgeon repositions the flap back over the exposed, newly contoured surface. Natural suction in your eye holds the flap in place, so no sutures are needed.  The entire surgical procedure should take less than 30 minutes. Most LASIK patients experience almost immediate results from the surgery and within two or three days will have normal, uncorrected vision.  There are actually two types of LASIK surgery: wavefront-optimized surgery (also referred to as “conventional LASIK”) and wavefront-guided surgery (also referred to as “custom LASIK”). The difference between these two types of LASIK procedures lies primarily in how the laser is programmed to reshape the cornea.  For conventional LASIK procedures, the surgeon completes an eye exam, takes measurements, and then enters this information into the computer that controls the laser. The computer is programmed with settings that determine how it will reshape the cornea, based on pre-set guidelines.  The newer, wavefront-guided technology is meant to be a customized, more accurate procedure that lets the surgeon program the laser to reshape the cornea according to each patient’s specific needs. Before the procedure, the surgeon uses computerized equipment that shines into the eye light that is reflected off the retina. The computer then measures how this light is distorted as it exits. The reflected light—or wavefront—is analyzed by the computer for distortions caused by imperfections in the cornea. The computer can then create a three-dimensional “thumbprint” of the cornea and this thumbprint is used to tell the laser exactly where and how much corneal tissue should be removed.  In theory, wavefront-guided LASIK should obtain more accurate results than conventional LASIK. During conventional LASIK, the laser tends to use the same power treatment over the center and sides of the cornea, but during wavefront-guided LASIK, the computer reshapes by different amounts over different areas of the cornea, theoretically allowing for a more perfect reshaping of the cornea.  Since wavefront-guided LASIK is still relatively new, there is little data available to determine whether it is in fact more accurate than conventional LASIK, although there is some evidence that the wavefront-guided LASIK technique does help to reduce the chances of having common problems such as poor night vision, halos, and blurry images after surgery.  Keep in mind that even if wavefront-guided LASIK proves to be more accurate with fewer post-surgery problems, the rates of success with conventional LASIK are very high, so any improvement gained by employing wavefront-guided LASIK is likely to be relatively minor. On the other hand, there doesn’t appear to be much difference in cost between the two procedures. Among surgeons we surveyed who offer both types of LASIK surgeries, we found that most charge the same fees for each.  Figure 2—The LASIK Surgery Process  LASEK and Epi-LASIK  LASEK (laser epithelial kerato- mileusis) or Epi-LASIK surgery may be an option for you if you’re not a good candidate for LASIK surgery. These two types of surgeries, which are very similar to one another, are usually used as alternatives to LASIK for persons who have thin corneas or who have jobs or play sports that carry a high risk of eye injury.  The LASEK and Epi-LASIK procedures are similar to LASIK, except that during LASEK and Epi-LASIK, only a very thin layer of corneal tissue is temporarily removed before exposing the cornea to the laser. The surgeon treats the top layer of cells of the cornea with an alcohol solution for about 30 seconds; this treatment loosens this thin layer of cells and allows it to be lifted and folded back by the surgeon. After the cornea is reshaped by the laser, the surgeon puts back in place this top corneal layer.  LASEK and Epi-LASIK cost about the same as LASIK procedures. Most patients undergo LASIK surgery instead of LASEK or Epi-LASIK because it usually takes more time for the cornea to heal—as long as several months—after LASEK and Epi-LASIK compared to LASIK. Also, LASEK and Epi-LASIK patients typically have longer visual recovery times (one to two weeks), compared to the one or two days with LASIK.  Aside from being an option for those with thin corneas or who have high risk of eye injury, the main benefit of LASEK and Epi-LASIK is that less cutting is required, and therefore fewer patients suffer from complications that result from cutting and reattaching the corneal flap that takes place during LASIK procedures. But these types of complications are rare—occurring in only between 0.1 and 0.3 percent of LASIK patients.  PRK  PRK (photorefractive keratec- tomy) was one of the first laser eye surgery methods developed for vision correction, but has largely been replaced by LASIK and other methods. Like LASEK and Epi-LASIK, PRK is usually performed for patients who have corneas that are too thin to undergo LASIK.  Unlike LASIK, LASEK, and Epi-LASIK, during PRK none of the corneal surface tissue is cut away to expose the corneal tissue underneath; instead, the surgeon uses a laser on the surface of the cornea to reshape it. After the surgery, a contact lens is placed on the eye and acts as a bandage for three or four days; eventually the raw surface of the cornea heals on its own.  Although PRK does not require any cutting and is about as accurate as LASIK, LASEK, and Epi-LASIK, it may still take three to six months for the cornea to heal enough so that the vision in the treated eye becomes normal. Also, since the corneal surface is made raw by the laser, patients who undergo PRK are more likely to have infections than those who have LASIK, LASEK, or Epi-LASIK. (For this reason, PRK patients almost always only have one eye treated at a time.) Since the healing time is so long, and since the procedure costs about the same as LASIK, LASEK, or Epi-LASIK, most patients just opt for one of the other procedures.  LTK  LTK (laser thermokeratoplasty) surgery is a new laser eye surgical technique that can be used to treat farsightedness and astigmatism. Unlike the laser eye surgeries described above, which use a “cool” laser, LTK is done using a “hot” laser that heats, shrinks, and reshapes the surface of the cornea. Unlike the other types of surgeries, LTK achieves its vision correction within a matter of seconds, without any cutting, removal, or abrasion of corneal tissue.  Since LTK causes virtually no trauma to the cornea, there is little risk of infection, vision loss, or other complications, and results are obtained very quickly with little or no healing required.  Although LTK is highly effective in the short-term, the results are not permanent. Usually, some regression of vision occurs during the first three months following surgery, and within two years, many of those who undergo the surgery lose about one-half of the corrective effects the surgery provided. Eventually, their surgeries will have to be repeated to re-correct the patients’ vision. Most surgeons using LTK will try to over-correct patients’ vision so that the regression doesn’t return vision to its pre-surgery state so rapidly.  Are You a Suitable Candidate?  Before deciding to have laser eye surgery, you should first discuss with a physician whether or not you are a good candidate for any of the available procedures. Some types of vision problems won’t be helped by surgery and, as we have noted, some of the surgical options aren’t appropriate for some people.  During an initial consultation, the surgeon and his or her team should check your eyes and measure your prescription, corneal thickness, corneal shape, pupil size, and other factors. It is important to let the surgeon and the surgeon’s team know if you take any medicines, have any allergies to medicines, or have any medical conditions. It is especially important to let the surgeon know if you are pregnant since visual acuity tends to change during pregnancy.  While problems can befall any patient, the risk is considerably higher for some than for others. If you have any of the following characteristics, you may not be a good candidate for laser eye surgery, or at least for some types of laser eye surgery—  If you currently need a large correction. If your vision is quite bad before surgery, there is a relatively high probability that laser eye surgery will not be enough to allow you to go without glasses. Also, you are more likely than other patients to have post-surgery vision problems like seeing glare or a halo at night.  If you required a change in your contact lens or glasses prescription in the past year. Such “refractive instability” is common in patients who are in their early twenties or younger, whose hormones are fluctuating due to a disease such as diabetes, who are pregnant or breastfeeding, or who are taking certain medications.  If you have a disease or are on medications that may affect wound healing. Diabetes, autoimmune diseases like lupus and rheumatoid arthritis, and immunodeficiency conditions like HIV may prevent proper healing after the procedure. The same is true of some medications like retinoic acid and steroids.  If you have presbyopia, a type of refractive error that becomes common as we age. To read a book or see other objects up close, your eye needs to focus light differently than when you are looking at more distant objects. When you are young, that’s fine because your eye has a lens behind the cornea that can adjust its shape to fine-tune the focus of the light. After about age 40, your lens becomes more rigid and your eye may not be able to make needed adjustments. This condition is called presbyopia and requires that you wear reading glasses. Since none of the surgical procedures can correct presbyopia, some patients who wear bifocals opt to have their vision corrected using “monovision,” where one eye is corrected to see objects far away and the other is corrected to see close objects. But some patients who undergo these procedures aren’t able to adjust to the changes and must continue to use eyeglasses.  If you work in an occupation or actively participate in contact sports in which blows to the face and eyes are a normal occurrence. LASIK surgery may not be an option for you, but you may still be a good candidate for other types of laser vision surgery.  If you have a history of certain eye-related conditions or problems, including dry eyes, herpes involving the eye area, suspected or actual glaucoma, ocular hypertension, inflammations of the eye or eyelids or crusting of the eyelashes, eye injuries or previous eye surgeries, or keratoconus.  If you have large pupils. Be sure the size of your pupils is measured in a dark room. Younger patients particularly are likely to have large pupils in dim lighting. One problem with large pupils is that, after laser eye surgery, at night when the pupil is dilated, light is likely to enter the eye through the portions of the cornea at the edge of where the laser did its cutting. The light is likely to be distorted in those areas.  If your cornea is thin. Again, you may not be a good candidate for LASIK surgery, but your doctor may be able to use an alternative procedure.  How Well Does It Work? What Can Go Wrong?  Most laser eye surgery patients experience dramatic improvement in how well they can see without eyeglasses or contacts.  About 85 percent of people who have undergone laser eye surgery no longer need glasses or contact lenses. But your results will depend on your specific error—particularly the severity of your error—and some other factors. Your chances of success are best if you have only minor error, especially if the problem is nearsightedness. Persons with a high degree of farsightedness along with astigmatism have the least predictable results. One academic survey concluded that more than 97 percent of patients who had had LASIK surgery were glad that they did.  But success is not assured. It is estimated that as many as 15 percent of LASIK patients have to undergo a second surgery because the initial correction is not sufficient. While re-treatment is often an option if the first correction isn’t optimal, even a re-treatment won’t always solve the problem, and in some cases, particularly if the surgeon has removed too much corneal tissue, re-treatment is not possible.  What’s more, visual acuity as measured on an eye chart is not all you care about in your eyesight. A 20/20 measurement means that from a distance of 20 feet, the smallest print you can read on a standard eye chart is the same size as the smallest print someone with “normal” eyesight can read. (A 20/40 measurement means that at 20 feet you can just read what a person with normal eyesight could read at 40 feet.) But being able to read an eye chart is not the same as having it look right. You might be able to read small letters although both they and the large letters look fuzzy or wavy to you. Unfortunately, that’s what some laser eye surgery patients experience.  Other problems with post-surgical vision include—  Seeing glare, especially at night;  Seeing halos and starbursts around lights at night;  Seeing too little contrast in dim light;  Loss of lines of vision—some lines simply not visible on the vision chart; and  Dry eyes.  Although such problems usually disappear over the first few months, for a small percentage of patients, they persist—and, in some cases, are uncorrectable.  Even worse problems, although rare, are infections and growth of surface-type cells under the repositioned flap or on the reshaped corneal tissue. It is estimated that infection from PRK occurs in less than 0.1 percent of patients; for LASIK, this number is even smaller. Fortunately, most infections can be treated and usually just mean discomfort and a longer healing process.  More serious complications are very rare; less than one in 5,000 LASIK patients experience permanent, serious complications.  A final point to keep in mind as you consider the possible results of surgery is that after age 40 you are likely to have to wear glasses or contacts for reading even if the correction obtained by laser eye surgery goes perfectly. This is because, as mentioned previously, laser eye surgery cannot correct presbyopia.  How Do You Find a Surgeon?  It is important to have a good doctor—to help you decide whether to have laser eye surgery, to make the measurements and assessments prior to doing the surgery, to perform the surgery, and for aftercare.  If you already have an ophthalmologist you trust, that is a head start. Ask this doctor whether he or she does laser eye surgery. If yes, then this doctor will be a good candidate to do surgery for you. But you still will want to check about experience, quality, and price.  Ophthalmologists tend to know a lot about their peers. They see patients whose eyes reveal the results of good and bad surgeries done by other doctors. They hear from patients and from hospital nurses and other personnel in the community. If you can arrange to talk with an ophthalmologist who doesn’t do laser surgery—many do not—ask him or her to recommend surgeons. The top-rated ophthalmologists listed in the Opticians article are good candidates; you can easily check which currently do laser surgery. You might also get useful feedback from an optometrist if you have a trusted one from whom you get eyeglasses or contacts.  You want a doctor who will give you plenty of “chair time”—who will take a thorough medical history, listen to your questions and concerns, and fully explain the procedure, the risks, and the alternatives in advance. It is essential that the doctor take careful measurements of your eyes to assess whether you are a good candidate for laser eye surgery and to determine exactly how the laser-eye-surgery equipment should be programmed to perform the procedure.  Experience is valuable. A doctor who has done many laser eye surgeries may be better able than a less experienced one to assess your suitability for the treatment. An experienced doctor might also be better able to deal with problems that might come up, like a malfunction of the equipment, an unintentional cutting through of the hinge of the flap during LASIK surgery, a post-operative infection, or the need to pry up the flap again to do a re-treatment if the first correction proves after several months to be unsatisfactory. Experience might also help a doctor reposition the flap properly after the laser has shaped the cornea.  Price is certainly a consideration. Most insurance companies consider laser eye surgery a cosmetic treatment. That means you have to pay out of your own pocket. The cost is substantial. And prices vary from surgeon to surgeon. In a survey of a sample of Chicago area surgeons, we found prices for LASIK surgery for two eyes ranging from less than $2,000 to more than $4,000.  You can easily shop for surgeons. Call several doctors’ offices and ask whether the doctor does laser eye surgery, how many surgeries the doctor has done in the past two years, the price—per eye or for two eyes—and what is included in the price.  When you identify a surgeon who seems to be a good choice, arrange for an appointment for an evaluation. With many doctors, that is a free service. During this evaluation, you will need to size up the doctor, both the “chair time” aspects of the visit and the thoroughness of the measurements—for instance, whether the measurement of pupil size is done in a dimly lit room. If you wear contact lenses, which can distort the shape of your cornea, it is a good idea to stop wearing them several weeks before your baseline examination so that the measurements that will be used to calibrate the surgical equipment will be based on the natural shape of your eye. If your doctor doesn’t advise you not to wear contacts before the exam, ask why not.  Many doctors do several hundreds, or even thousands, of laser eye surgeries per year. If you are making your choice of surgeon in part based on their laser-eye-surgery experience, you will want to confirm claims of number of surgeries done. You might ask the doctor for something in writing stating this count, or you might send the doctor a note confirming that you will be using him or her for the surgery and explaining that one reason for your choice was “your statement that you have done [type of surgery] on [number] of eyes in the past two years.”  If after an evaluation visit you are not confident about a doctor, try another one. If you like the doctor but are not fully confident that you are a good candidate for the surgery—keeping in mind that doctors have a financial incentive to encourage patients to get surgery—go to another doctor for a second opinion.  During the consultation process, you might want to ask about alternatives to the various laser eye surgeries. We have focused on the most common types of surgeries here, but there are other options.  What to Expect After LASIK Surgery  After the surgery, it is important that you not rub your eye or allow it to be inadvertently poked—including while you sleep—to assure that the flap is not dislodged. For protection immediately after the procedure, a shield should be placed over your eye. Your doctor will probably remove it at the first follow-up visit the day after your procedure.  You can expect improvement in your ability to see without glasses—your ability to read an eye chart, for instance—within the first day. And for many patients, this ability continues to improve for several months. During the days and months following the surgery, you can also expect the following:  For three days—mild discomfort and pain, burning or scratchiness, tearing or watery eyes.  For one week—sensitivity to light, hazy or blurred vision.  For one month—dry eyes, seeing glare and halos around lights at night, and difficulty driving at night.  For six months—fluctuations in your vision before your condition finally stabilizes.  Many patients go back to work the day after surgery, but others take a few days off. You should see your doctor within a day after surgery, again within one or two weeks, and then have regular visits for about six months after that. After the surgery, your doctor will probably give you anti-infection, anti-inflammatory, and lubricant eye drops to take with you. You should not wear contact lenses, even if your vision is blurry, without specific approval of your doctor. You will have to restrict some activities. Your doctor will probably advise—  No non-contact sports for at least three days.  No eye makeup for two weeks.  No strenuous or contact sports for at least four weeks.  No swimming, whirlpool, or hot tub for at least eight weeks.  Return to My Personal Member Homepage Back to top