Many people are not blessed with perfect vision throughout their lives. For the past 700 years, this meant wearing eyeglasses to correct errors in refractive vision. In the 1950s, contact lenses were invented, providing a less visible way to achieve vision correction. Modern research has made possible several methods of corrective eye surgery. These include procedures like PRK and LASIK that reshape the surface of the eye using a laser and correcting eyesight through surgically inserted artificial lenses.
Eye surgery that improves the refractive condition of the eye and decreases or eliminates the need to wear contacts or glasses is called refractive eye surgery. Myopia, astigmatism, hyperopia, and other common vision disorders are corrected through this surgery. It has increased in popularity, with over 900,000 patients on an annual basis. Though the surgery seems relatively new to many of us, the first studies were published in 1896.
Myopia, also called nearsightedness, occurs when incoming light does not directly focus on the retina, causing a faraway image to appear out of focus. Commonly called farsightedness, hyperopia is due to an imperfection within the eye that makes it difficult to focus on nearby objects. In extreme cases, a sufferer may also not be able to focus on objects in the distance. The optical defect astigmatism results in blurred vision because the optics of the eye are unable to convert an object into a sharp, focused image.
Laser surgery has made great strides in the past 25 years. During the 1980s, radial keratotomy was the primary method used in the U.S. This involved flattening the surface of the eye by cutting incisions designed to correct nearsightedness. Long-term side effects like issues with night vision, regression, and glare led this procedure to become nearly obsolete. What replaced it was photorefractive keratectomy (PRK), the first laser vision correction surgery that successfully removed tissue from the eye surface, changing the curvature of the cornea.
PRK was approved by the FDA in 1995 and was popular until LASIK arrived on the scene. However, it has recently made a resurgence because it has similar results to LASIK and features faster nerve generation on the surface of the eye. LASIK involves cutting a thin, hinged flap on the surface of the eye but PRK is entirely a surface procedure, reducing flap complications and used on patients with thin corneas.
Benefits of LASIK include little to no discomfort immediately following the procedure and clear vision within hours, not days. There are different forms of LASIK and many of them are characterized by how the flap is created. LASEK involves floating the thin flap away from the surface using alcohol in order to reshape the eye using a laser. Epi-LASIK makes use of a special cutting tool to lift the flap. Bladeless LASIK uses a laser rather than a cutting tool to make the flap.
Wavefront LASIK measures how light travels through the eye, using ultra-modern analysis. Lasers featuring wavefront analysis automatically adjust for even subtle errors in vision. According to studies, this process reduces risk of night glare and maintains sensitivity to contrast. Conductive Keratoplasty applies spots around the periphery of the clear front surface of the eye using a tiny probe and radio waves. This provides farsighted individuals with improved vision because it steepens the cornea.
Individuals who feel they are candidates for laser eye surgery should first consult with a vision professional. The correct form of laser surgery depends on the vision error and age of the patient. Children younger than 18 are usually not candidates for these procedures and people with certain diseases or conditions may only be eligible for certain types. Lifestyle is also an important determinant of the proper type of laser surgery because the result must be compatible with the occupation and activities of the individual.