LASIK is the most popular corneal refractive procedure worldwide, with so many procedures performed each year. LASIK produces excellent results when performed by a skilled eye doctor, and although it’s not an ophthalmologic cure-all, the technology is adaptable to a wide variety of vision problems.
How LASIK Works
The concept behind LASIK — or laser assisted in situ keratomileusis — is fairly straightforward. Your cornea accounts for much of your eye’s focusing ability, and irregular or abnormally shaped corneas cause blurry vision. Reshaping the corneas with LASIK can often compensate for blurred vision due to these abnormalities, which doctors call refractive errors. During a LASIK procedure, your doctor uses a blade or laser to create a flap on the front of your cornea. The flap is carefully folded back, and the underlying cornea is reshaped with a laser. The flap is then returned to its original position. No stitches are required, and postoperative discomfort is usually minimal.
People with myopia, or nearsightedness, have trouble focusing on far-away objects. If you are nearsighted, or myopic, without corrective lenses you have problems seeing well at a distance, but may be able to see clearly up-close. Nearsightedness is a refractive error caused by the cornea being too curved, resulting in light being focused in front of the retina rather than on the retina. Laser vision surgery for the correction of nearsightedness is accomplished by flattening the central cornea, thus allowing light to focus correctly on the retina.
During the procedure, pulses of cool, ultra-violet light are emitted from a computer-guided Excimer laser to remove corneal cells according to your unique prescription. More LASIK procedures are performed to correct myopia than any other vision problem.
While most LASIK patients are primarily interested in correcting nearsightedness, the procedure is also commonly used to deal with other refractive problems.
People with hyperopia, or farsightedness, have trouble focusing on nearby objects. If you are farsighted, or hyperopic, without corrective lenses you have problems seeing well up close, but are able to see objects in the distance more clearly. Farsightedness is a refractive error caused by the cornea being too flat, or the eye being too short, preventing light from focusing on the retina. The laser vision correction of farsightedness is accomplished by steepening the central cornea, thus allowing light to focus correctly on the retina. During the procedure, pulses of cool, ultra-violet light are emitted from a computer-guided Excimer laser to remove corneal cells according to your unique prescription.
If you have astigmatism, without corrective lenses you experience overall blurry vision, shadowing, or distortion of your vision. Astigmatism is a refractive error caused by the cornea having an oval, or football shape resulting in light focusing on multiple points around the retina rather than a single point on the retina. If the surface of your cornea is shaped more like a football than a baseball, the light entering your eye bends unequally. This produces sharp images in some areas of your field of vision and fuzzy images in others. The type of astigmatism you have is determined by the direction and extent corneal warping. Many people with astigmatism also have myopia or hyperopia.
The LASIK correction of astigmatism is accomplished by smoothing out the irregularities of the cornea at the precise points of astigmatism, thus allowing light to focus correctly on the retina.
More than 95 percent of patients undergoing LASIK are satisfied with the results of their surgery, regardless of their original vision problem. Before you proceed with laser vision correction, schedule a consultation with a LASIK doctor who will perform a thorough evaluation to determine if LASIK is a good option for you.
This post originally appeared at Lasik Plus.