There are several modern approaches to corrective eye surgery available ranging from laser reshaping of the eye's surface in procedures such as LASIK and PRK to surgical insertion of artifical lenses to correct eyesight.
In LASIK and PRK, laser energy reshapes the curvature of the eye's clear front surface (cornea) to alter the way light rays enter the eye. Artificial lenses surgically inserted into the eye also can refocus light rays to sharpen vision.
Photorefractive Keratectomy (PRK) was the first successful laser vision correction procedure used to remove (ablate) directly from the eye's surface to change the curvature of the cornea. PRK, also known as surface ablation, was performed outside the United States during the 1980's and received FDA approval in 1995. Because PRK is a surface procedure, there also is no risk of surgical flap complications. PRK does not involve creating a thin, hinged flap on the eye's surface, as occurs with LASIK. PRK also appears to be a safer procedure in cases when a person's cornea may be too thin for LASIK surgery.
LASIK (Laser-Assisted in Situ Keratomileusis) is like PRK, except that a thin, hinged flap is made in the eye's surface. This flap is lifted, and then laser energy is applied underneath to reshape the eye with an Excimer laser. The flap is replaced and functions as a natural bandage. LASIK's main advantage over PRK is that there is little or no discomfort immediately after the procedure, and vision is usually clear within hours rather than days.
Some patients may experience eye discomfort, watery eyes, as well as sensitivity to light immediately following the procedure. During the recovery process, it is important for patients to avoid rubbing their eyes, since this can make the discomfort worse.
Problems with dry eyes are very common following LASIK surgery and patients will be sent home with eye drops designed to add moisture to the eyes.
Patients may experience problems with fluctuation of vision and night vision during the first few weeks following surgery, including halos, night glare and starbursts. This is generally caused by the normal post operative healing of the eyes, and it should gradually diminish as time goes by.
Because your eyes change as we age, the type of laser eye surgery or other vision correction you need also may change. Certain approaches to LASIK or other procedures that work well for younger adults, may be inappropriate for older individuals. In some cases, vision correction surgery may be ruled out entirely. Children under age 18 rarely would be considered candidates for laser vision correction because their eyes change too rapidly as their bodies grow and mature. Also, some people have certain condition or diseases that would make them poor candidates for certain vision correction procedures.
Generally speaking, however, people in their 20's or 30's with mild to moderate farsightedness, nearsightedness, and/or astigmatism are usually excellent candidates for laser vision correction.