Vision-correcting laser surgery has become so commonplace these days that virtually all of us either know someone who has had the procedure or have had it ourselves.
Laser-assisted in situ keratomileusis (LASIK) is, in fact, the most commonly performed elective surgery worldwide.
Problem: Despite the popularity of LASIK, most people don’t fully understand what it entails — or what it can and cannot do.
Common myths…
Myth 1: It’s not “real” surgery. LASIK requires only eyedrops for anesthesia, and most patients experience little or no pain. But LASIK, which involves reshaping the cornea to improve vision, is still surgery — and it’s not a trivial procedure.
What happens: A laser cuts a hinged flap away from the front of the eye, which is folded back to access and reshape the cornea. This changes how light focuses on the retina, thus improving vision.
Like any surgical procedure, LASIK has risks. Example: In rare cases, patients suffer postsurgical side effects, such as eye dryness, oversensitivity to light and/or seeing glare or halos at night. These problems usually clear up within a few weeks, but some patients continue to have discomfort for up to a year.
More serious risk: Long-term vision impairment — that is, being able to read fewer lines on the eye chart. This affects fewer than one in 10,000 patients nationwide, and can be caused by a poorly made flap, infection or problems with healing. In rare cases, patients continue to have dryness or visual disturbances (such as glare) for the rest of their lives. This can potentially be treated with medicated eyedrops or further surgery.
Important: Only medical doctors are allowed to perform LASIK surgery. The doctor you choose should be board certified by the American Board of Ophthalmology.* This ensures that the surgeon has completed the rigorous examination process required by this board.
Before agreeing to do the procedure, the doctor should perform a comprehensive exam. The exam should take at least 60 to 90 minutes and include reviewing your detailed medical history and measuring your cornea with special equipment to ensure that you’re a good candidate for LASIK and that your risk for complications is low. When you see the doctor for a consultation, also be sure to ask about the age of his equipment. Lasers older than about five years won’t have the latest improvements.
Myth 2: Everyone with vision impairment can have LASIK. Virtually everyone who wears contact lenses or eyeglasses will have better vision after undergoing LASIK. This doesn’t mean that it’s always the right procedure.
Patients with eye problems that go beyond simply needing glasses, such as keratoconus (when a normally round cornea becomes irregular), an unusually thin cornea, large pupil size or dry eye syndrome, should not undergo LASIK. The risk for complications — or bad results — is too high.
In addition, LASIK is not recommended for patients with macular degeneration, cataracts or other eye diseases, or for those with diabetic retinopathy or disorders of the optic nerves. These patients may be candidates for other surgical procedures to address their conditions.
Myth 3: LASIK is only for nearsightedness. That’s not true. In fact, LASIK is as effective for farsightedness (hyperopia) as it is for near-sightedness (myopia).
The process of reshaping the cornea will depend on your type of vision problem. If you’re nearsighted, your cornea is too steep and the surface of the cornea will be slightly flattened to correct your vision. If you’re farsighted, more tissue might be removed from the sides to make the cornea steeper.
Myth 4: LASIK doesn’t work for astigmatism. LASIK is better than glasses or contact lenses for treating astigmatism, in which one’s vision is out of focus due to a cornea that is not perfectly round. That’s because the surgeon can change the shape of the cornea at a precise location with LASIK.
Myth 5: LASIK doesn’t eliminate the need for reading glasses. Age-related vision loss, or presbyopia, happens to virtually everyone after about age 40. It has nothing to do with the shape of the cornea. Instead, the eye’s lens loses its ability to focus on nearby objects. This is why people sometimes read by holding a book or a menu farther away from their eyes.
LASIK won’t eliminate presbyopia, but it can be used to improve both distance and close-up vision, a technique known as blended vision.
Unlike monovision, in which one eye is fully corrected for distance vision while the other is fully corrected for close up, blended vision is a compromise. The dominant eye is corrected for distance vision, and the nondominant eye is adjusted slightly toward near vision.
This approach allows patients to see better at all distances. Many can read or do close work (such as using the computer) without using reading glasses. At the same time, they can see faces or signs at a distance. With blended vision, only some patients need reading glasses in low light or to read fine print.
The problem with traditional monovision is that the brain can’t always adjust to the large disparity between the two eyes. But most patients adjust to blended vision within a few days after LASIK.
Myth 6: LASIK doesn’t ever need to be repeated. LASIK permanently changes the shape of the cornea. However, the eyes can change with age whether or not you’ve had LASIK. This means that many patients eventually will need a subsequent procedure just as they need to change their prescription for glasses now and then. This typically happens many years after LASIK surgery as the eye ages.
In rare cases (fewer than 5% of all patients), LASIK can result in under- or overcorrection due to the laser removing too much or too little tissue from the eye. When this happens, you will need a follow-up surgery to see clearly.
Important: Ask your doctor about this risk before undergoing LASIK. Most specialists will charge a minimal amount, or nothing, for surgery to fix under- or overcorrection.
*To find out if a doctor is board certified, contact The American Board of Medical Specialties, 866-275-2267, www.abms.org.
