The familiar term, LASIK, is an acronym for laser-assisted in situ keratomileusis, which is a form of surgery ophthalmologists perform on patients suffering from a host of visual complaints, including nearsightedness, farsightedness, and astigmatism. This type surgery, using a laser instead of more traditional surgical tools, is called refractive surgery because it alters the shape of the surface of the eye so light, and therefore vision, is processed differently. Refractive surgery techniques are not limited to the LASIK procedures and lasers are used for other surgical procedures as well.
Most candidates for LASIK surgery have a history of wearing eyeglasses or contact lenses for vision correction and view surgery as a final solution to the daily hassles associated with glasses and contacts. Studies vary but the American Society of Cataract and Refractive Surgery estimates a 95.4% rate of satisfaction following LASIK surgery. This success rate, reported in March 2008, involved evaluation of 19 studies involving 2,200 patients and review of more than 3,000 LASIK-related articles published in medical journals during the previous 10-year period.
Nearsightedness, or myopia, is the most common ailment treated via LASIK but, as technologies improve, more and more patients suffering from farsightedness (hyperopia) and astigmatism are undergoing laser surgeries, too. Best results seem to come from patients who experience only mild to moderate levels of visual distortion.
Individual need determines which variation of LASIK is most appropriate for a given patient but the training and expertise of the surgeon is another consideration, as procedures vary. In any case, the best outcomes are achieved only after a thorough eye examination that involves full dilation of the pupils and the results evaluated by qualified professionals. LASIK is not a cosmetic procedure and must never be taken lightly.
As a general rule, surgery involves using a laser to slice off the corneal layer that covers the eye lens, leaving just a flap of tissue holding the flap to the eye. This flap is then folded back, revealing the surface of the lens underneath. At this point, the surgeon will guide the laser as it resculpts the natural curvature of the eye lens. Visual acuity is determined by the curvature of the lens and distance from the retina at the back of the eye. LASIK optimizes curvature to produce the best vision possible. Once the eye has been resurfaced, the corneal flap is replaced so the healing process can reattach it firmly and permanently in place.
LASIK works best on young adults who have enjoyed stable vision for at least two years prior to surgery. A growing number of middle-aged patients, however, are turning to laser surgery to eliminate the need for reading glasses caused by the aging process. This procedure, called slight monovision, mimics the effect of bifocal glasses.
To achieve monovision, the LASIK surgeon sculpts the patient’s dominant eye to better perceive distance vision while the non-dominant eye is sculpted so visual acuity is similar to the reading glasses the patient has been using. Post-surgical results require a period of adjustment, just as bifocal lenses do, but most patients report satisfactory results. Many surgeons fit a perspective monovision patient with contact lenses that replicate post-surgical effects so the patient can spend a few days becoming familiar with the projected outcome before committing to surgery.
While the vast majority of patients declare the surgery a success, satisfaction cannot be guaranteed nor is it 100%. Some patients become dismayed with blurry vision following surgery but, in many cases, the blurring clears over time. Because each patient is unique, the healing process varies from person to person. Some people report clear vision within a week or two but others experience permanent blurring.