Laser Eye Surgery

laser

Laser Eye Surgery

They fall off, fog up, get sat on, forgotten, lost. Sure, glasses and contacts do the job, but they can be a nuisance. Why can’t your eyes just work right on their own?

Plenty of laser-eye-surgery purveyors would love for you to pay several thousand dollars on an operation to fix your eyes for good. The procedure is quite safe, and most patients are satisfied—more than 95 percent of them, according to an extensive literature review sponsored by the American Society of Cataract and Refractive Surgery. But keep in mind also that what you get is still surgery. Before committing to it, think carefully about the various procedures available, the chances of a successful correction given your vision and other factors, the risks of complications, which surgeon to use, and costs. This article will get you started.

What Are the Options?

While there are several laser-eye-surgery options, LASIK surgery currently is by far the most common and, for most consumers, best option.

All of the surgical methods reshape the cornea, the curved transparent covering at the front of the eyeball. Along with the lens, the cornea focuses incoming light onto the retina at the back of the eye in much the same way a camera lens focuses light on film. If the cornea is improperly shaped relative to the length and shape of the eyeball, light will not focus properly and you will be nearsighted or farsighted, or have astigmatism.

Although all surgical options alter the shape of the cornea to optimally focus light onto the retina, there are slight differences in the way surgeries are performed.

LASIK

During LASIK (laser-assisted in-situ keratomileusis) surgery, the patient’s eye is anesthetized with eye drops while the eye not being treated usually is taped shut. After a device is attached to help the patient keep the treated eye open, the patient is told to look at a colored light to help keep his or her gaze forward.

The surgeon begins by holding the eye in place using a suction ring. The surgeon then cuts a thin flap of corneal tissue, which is lifted away from the surface of the cornea while still hinged at one end. After the flap has been created, the suction ring is removed.

The surgeon then uses a laser to remove tiny amounts of corneal tissue, thus reshaping the cornea into the desired contour. The laser is guided by information that has been programmed into its controlling mechanism—information about your unique prescription and other eye specifications.

When the reshaping is complete, the surgeon repositions the flap back over the 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 quickly experience its benefits and within two or three days enjoy normal uncorrected vision.

Bladeless LASIK Option

Eye surgeons disagree as to whether this newer method of using a laser to cut the flap—often advertised as “bladeless” or “all-laser” LASIK—is preferable to the traditional method that uses a special mechanized surgical blade. Those who prefer a blade argue that it shortens the most uncomfortable part of the procedure for the patient: The suction needed to hold the eye still usually lasts only three seconds with a blade but takes 15 to 20 seconds with an all-laser procedure. But surgeons who prefer the all-laser method argue that the flap it creates is more perfectly shaped, with sharper edges and a consistent thickness that heighten chances that the flap will heal quickly and without complications.

Some studies comparing the two methods suggest that all-laser LASIK results in slightly faster average visual recovery times and even slightly better success rates in terms of restoring 20/20 vision without corrective lenswear. But other studies found no significant differences in results. Even the studies that found evidence of improved outcomes with the all-laser method conclude the benefits are quite small.

Many experts—including many surgeons—insist that the main reason some surgical centers favor the all-laser approach is that it is more marketable.

Because surgeons pay a royalty to the cutting device’s manufacturer each time the all-laser procedure is performed, surgical fees for the all-laser approach are usually higher. Our advice is to compare the costs of the two methods and discuss the options with any surgeons you’re considering. Ask them if they have a preference and, if so, to explain why. Keep in mind that surgeons who heavily favor one method over the other perform many more surgeries using their preferred method. Since practice does indeed help make perfect, and since there doesn’t seem to be a significant difference in outcomes, you may want to choose the method your surgeon prefers.

Custom LASIK Option

There are two ways to program the laser device that shapes the corneal material in LASIK surgery—“conventional LASIK” and “custom LASIK.”

With conventional LASIK, the device is programmed according to lower-order aberrations of vision—your eyeglass prescriptions for nearsightedness, farsightedness, and astigmatism. This approach corrects your vision according to how well you can see a standard 20/20 eye chart.

Custom LASIK (also referred to as “wavefront-guided LASIK” or “wavefront-optimized LASIK”) measures and takes into account both lower-order and higher-order aberrations that may cause lack of contrast sensitivity and inability to discern fine detail. Unlike conventional LASIK, which would offer the same treatment to two patients with the same eyeglass prescription, custom LASIK takes into account the steepness and shape of patients’ eyes, often producing better night vision and sharper vision. Custom LASIK aims to reduce the risk of post-LASIK complications like glare, halos, and difficulty with night vision.

Evidence that custom LASIK surgery produces better results than conventional LASIK is very limited. Nonetheless, almost all surgeons who perform it strongly argue that custom LASIK achieves better results. But keep in mind that you can save a considerable amount of money by opting for the conventional LASIK procedure: Among area surgeons who still offer both types of procedures, we found that several charge less for conventional LASIK—sometimes a difference of $2,000 or more.

Choosing a LASIK Option

If you are having trouble deciding between custom LASIK and conventional LASIK, or whether to seek out a surgeon who uses the bladeless-laser method rather than a traditional blade, keep in mind that all these options have very low rates of serious complications. We suggest you focus your decision-making not on method but on finding a surgeon who is experienced, competent, skilled, and careful (see “How Do I Find a Surgeon?” below).

PRK

PRK (photorefractive keratectomy), one of the first laser-eye-surgery methods developed for vision correction, has largely been replaced by LASIK. PRK is still used for patients whose corneas are too thin to undergo LASIK or who have jobs or play sports that carry a high risk of eye injury.

Unlike LASIK, PRK involves cutting none of the corneal surface tissue to expose the corneal tissue underneath; instead, the surgeon uses a laser to reshape the surface of the cornea. After surgery, a contact lens is placed on the eye to act as a bandage for three or four days; eventually the raw surface of the cornea heals on its own.

The long-term results from PRK are as good as those of LASIK, and PRK costs about the same. But while PRK requires no cutting, it may take two months or more for the cornea to heal sufficiently to restore normal vision—which explains why PRK is performed only on patients who specifically need it.

LASEK and Epi-LASIK

Like PRK, LASEK (laser epithelial keratomileusis) or Epi-LASIK surgery are options for those who are not good candidates for LASIK surgery because they have thin corneas or 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 the thin layer of cells enough to allow the surgeon to lift it and fold it back. After the laser reshapes the cornea, the surgeon replaces this top corneal layer.

LASEK and Epi-LASIK cost about the same as the standard LASIK procedure.

Like PRK, with LASEK and Epi-LASIK, patients usually have fast initial vision recovery. But about two weeks post-surgery, they experience blurred vision for several weeks as their eyes discard wounded cells and replace them with new ones. Full visual recovery usually takes six to eight weeks.

Many surgeons no longer perform LASEK or Epi-LASIK procedures, but instead rely on PRK for patients who aren’t good candidates for LASIK.

Monovision LASIK

Beginning at age 40 or so, the lenses in one’s eyes begin to lose their flexibility. For most people, this means vision is not equally good at all distances, even while wearing eyeglasses or contacts or after LASIK surgery. Most people between ages 40 and 50 eventually need eyeglasses or other help for close-up vision, a condition called “presbyopia” that can be remedied with multifocal eyeglasses or multifocal contact lenses. It can be dealt with by laser eye surgery if the dominant eye is corrected to see objects far away, and the other eye corrected to see close objects. But some patients who undergo LASIK to treat presbyopia are unable to adjust to these changes—particularly when it comes to depth perception—and must continue to use eyeglasses. The best way to test if monovision LASIK is right for you is to simulate the results of the surgery by wearing contact lenses: If your eyes can adjust to monovision treatment with contacts, they should adjust well to monovision LASIK.

ICL

ICL (implantable collamer lens) surgery isn’t laser surgery, but it’s a procedure commonly used for patients who are poor LASIK candidates. During ICL surgery a very small incision is made in the eye and a rolled-up soft flexible lens made of collagen and polymer is inserted underneath the cornea. After insertion, the lens is unrolled and positioned so it reshapes the cornea to its ideal proportions. Because the incisions are so small, no sutures are necessary.

Although implants are primarily used for patients who cannot undergo LASIK, another reason to consider them is that they can be surgically removed if you are unhappy with the results.

Research is ongoing, but it appears that implants are as safe as, if not safer than, LASIK procedures and produce similar results.

Are You a Good Candidate?

Before deciding to undergo laser eye surgery, discuss with a physician whether or not you are a good candidate for any of the available procedures. Surgery won’t help some types of vision problems and, as we have noted, some surgical options are inappropriate for some people.

During the initial consultation, the surgeon and his or her team should check your eyes and measure your eyesight, corneal thickness, corneal shape, pupil size, and other factors. Tell the surgeon if you take any medications, are allergic to any medications, or have any medical conditions. It is especially important to inform the surgeon if you are pregnant because visual acuity may change during pregnancy.

Your Age

Your age, and how long you are likely to be able to enjoy the full benefits of laser eye surgery, are major considerations.

First, you must be old enough for your eyes to have stabilized. People in their early 20s or younger often have significant “refractive instability,” which means corrections made by laser surgery might lose their effectiveness as their eyesight changes.

Second, people in their 20s, 30s, and early 40s need to be aware that the freedom from glasses and contacts that results from the most common laser surgery procedures is not likely to be permanent. As noted above, most people after age 40 or 45 find that their eyes begin to lose their flexibility. If they see well at a distance, possibly as a result of laser surgery, their eyes may not be able to adjust to focus well close up, and they may need reading glasses.

Surgery to make one eye farsighted and the other nearsighted could be a lasting solution for people whose brains can adjust to this setup, but some can’t.

Other Considerations

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—

What Can Go Wrong?

Most patients experience dramatic improvement in how well they can see without eyeglasses or contacts. Estimates vary, but studies indicate that well over 50 percent of patients who undergo laser eye surgery achieve 20/20 or better, and over 90 percent achieve 20/40 or better (good enough to drive without corrective lenses). Surveys indicate that more than 95 percent of LASIK surgery patients are satisfied with the results.

But there is still a chance that laser eye surgery might not completely correct your vision so well that you no longer need to wear lenses. The odds of surgical success in terms of vision correction depend on your specific error—particularly the severity of your error—and other factors.

If you have only minor error, and especially if you are nearsighted, your chances of success are the highest. For persons with farsightedness and farsightedness with astigmatism, chances of success are lower; if you have a high degree of farsightedness along with astigmatism, the results are the least predictable.

When the initial correction from LASIK is insufficient, some patients undergo a second surgery. But re-treatment won’t always solve the problem, and, in some cases, re-treatment is not possible (particularly if the surgeon has removed too much corneal tissue).

What’s more, visual acuity as measured on an eye chart is not all you care about. 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 read only what a person with normal eyesight could read at 40 feet.) But the ability to read an eye chart is not the same as having it look right. You might be able to read small letters even if both they and the large letters look fuzzy or wavy. Unfortunately, that’s what some laser eye surgery patients experience.

Other problems with post-surgical vision include—

Although such problems usually disappear after the first few months, for a very small percentage of patients they persist—and in some cases are uncorrectable.

Other problems, although rare, are infections or growth of surface-type cells under the repositioned flap or on the reshaped corneal tissue. Fortunately, most of these problems can be treated if discovered promptly through proper follow-up care, and usually just cause discomfort and extend the healing process.

How Do I Find a Surgeon?

It is vital to find a good surgeon—to help you decide whether to have laser eye surgery, to make measurements and assessments prior to surgery, to perform the surgery, and for aftercare.

Experience is very important. Some doctors perform more than 1,000 of these surgeries per year. Studies have shown that doctors performing their first few hundred surgeries with a specific technique are at least twice as likely to produce complications or poor results as more experienced doctors. Also, doctors who have performed many laser eye surgeries may be better able than less experienced ones to correctly assess your suitability for the treatment. And an experienced doctor is likely to better handle problems that might come up, including malfunctioning equipment, unintentionally cutting through the hinge of the flap during surgery, post-operative infection, or the need to pry up the flap again for re-treatment several months later.

Getting Referrals

If you already have an ophthalmologist you trust, you have a head start. Ask this doctor whether he or she often performs laser eye surgery. If so, this doctor is a good candidate. If not, he or she can recommend surgeons who perform laser eye procedures. A trusted optometrist can also provide referrals. But you still need to find out about the surgeon’s experience, quality, and price.

Ophthalmologists tend to know a lot about their peers. They see patients whose eyes reveal the results of successful surgeries performed by other doctors—and of unsuccessful ones. They hear from patients, hospital nurses, and other personnel in the community. If you can arrange to talk with an ophthalmologist who does not perform laser surgery—many do not—ask him or her to recommend surgeons.

Another good resource, either for finding experienced laser eye surgeons or for recommendations of surgeons, are the ophthalmologists listed in our “Top Doctors” section. To create our Top Doctors lists, we surveyed virtually all actively practicing physicians in the nation’s 53 largest metropolitan areas and asked them to name the one or two physicians in each of 38 specialty fields they “would consider most desirable for care of a loved one.” Our Top Doctors lists identify the doctors mentioned most often by their peers and how many mentions each received—along with basic information such as office addresses and phone numbers, medical schools attended, and board certification.

Another source of information about prospective surgeons is the nonprofit Council for Refractive Surgery Quality Assurance (CRSQA), an independent organization that accredits surgery centers based on the results of surveys in which patients rate the performance of practices on several elements of care, including overall satisfaction, whether the desired goal was achieved, and whether there were complications. To become fully certified, a practice must score in the 90th percentile of their peers on key quality measures. To maintain certification, practices are reevaluated each year. For a current list of certified practices, visit the CRSQA’s website at www.usaeyes.org.

Shopping Around

In addition to a surgeon who has experience, you want one who gives you plenty of “chair time”—who takes a thorough medical history, learns about your visual needs and goals, listens to your questions and concerns, and fully explains in advance the procedure, risks, and alternatives. 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.

Price is certainly a consideration. Most insurance companies consider laser eye surgery a cosmetic treatment, which means you have to pay for it out of pocket. And the cost varies substantially from surgeon to surgeon: Our survey of a sample of area surgeons found prices for custom LASIK surgery for two eyes, using the all-laser cutting procedure, ranging from less than $4,000 to more than $7,000.

It’s easy to shop for surgeons. Call several doctors’ offices and ask whether the doctor performs laser eye surgery, how many surgeries the doctor has performed in the past two years, the price—per eye or for two eyes—and what the price includes.

When you identify a surgeon who seems promising, make an appointment for an evaluation. With many doctors, this is a free service. Before the evaluation, write down your questions so you don’t forget to ask them. The article “50 Tough Questions for Your LASIK Doctor,” available at CRSQA’s website (www.usaeyes.org), will help you make your list. Size up the doctor, both the “chair time” aspects of the visit and the thoroughness of the measurements. If you wear contact lenses, which can distort the shape of your cornea, stop wearing them a week or so before your baseline examination so that the measurements 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.

Ask any surgeon you’re considering how often his or her patients have suffered serious complications following surgery, mild complications after surgery, and what total percentage of patients have failed to attain uncorrected 20/20 vision after surgery. The benchmark for any practice should be no serious complications, no or very few mild complications, and a very high success rate in terms of achieving visual accuracy.

Since many doctors perform several hundred, or even thousands, of laser eye surgeries per year, but some perform fewer, you should ask about experience. And confirm claims of number of surgeries done. Ask the doctor to put something stating this count in writing, or 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 performed [type of surgery] on [number] of eyes in the past two years.”

If after an evaluation visit you have no confidence in the surgeon, try another one. If you like the surgeon but are not convinced that you are a good candidate for the surgery—keeping in mind that doctors have a financial incentive to encourage patients to get surgery—get a second opinion.

During the consultation process, ask about alternatives to the various laser eye surgeries. We have focused here on the most common types of surgeries, but there are other options.