Other Refractive Procedures

LASIK is the best-known refractive procedure, but not the only one. Refractive eye surgery is done to improve the eye’s ability to correctly refract (bend) light. Clear vision depends on the eye being able to focus incoming light clearly on the retina. This refraction is done first by the cornea (about 60 percent) and then by the lens (40 percent).

The lens is able to change its shape and thus bend light at different angles. This is called accommodation – the lens becomes flatter for distance vision and steeper for near vision.

Refractive Procedures Using a Laser

The cornea has a fixed shape (curvature) and cannot adapt to different distances. LASIK and its variant procedures use an excimer laser to remove (ablate) part of the cornea to change its curvature. They do this on the cornea’s middle layer, the stroma. Access to the stroma it is gained by creating a surface flap and folding it back out of the way.

By modifying how this flap is created, or by not creating a flap at all, these procedures may give good results for many who are not good LASIK candidates.

PRK (Photorefractive Keratotomy) – removes surface corneal tissue, allowing it to regrow during recovery
Epi-LASIK – removes surface tissue using alcohol and a spatula-like implement and replaces it after the procedure
LASEK (Laser Assisted Sub-Epithelium Keratomileusis) – creates an extra-thin corneal flap using a finer blade than LASIK
IntraLase (also called iLASIK) – uses a second laser to create the flap, thus avoiding blades completely. Learn more by reading LASIK vs. Intralase.

The three vision problems LASIK and its variants correct are:

Myopia (nearsightedness)
Hyperopia (farsightedness)
Astigmatism (blurriness at all distances)

Non-Laser Refractive Procedures

Conductive Keratoplasty (CK)

Conductive Keratoplasty also reshapes the cornea but does not use a laser. It uses radio waves to treat hyperopia and presbyopia (age-related blurriness of near vision). The radio energy shrinks tissue around the corneal periphery, giving it a steeper curvature.

Radial Keratotomy (RK)

Radial Keratotomy uses a diamond knife to made slanting incisions around the outside of the cornea. This has the effect of flattening the corneal curvature, thus improving myopia.

Laser Thermal Keratoplasty (LTK)

Laser Thermal Keratoplasty is similar to CK, in that it shrinks corneal tissue to treat hyperopia. Instead of using radio waves, it uses a Holmium laser, which is a warm, infrared laser. Like CK, it is also used to treat presbyopia.

Refractive Procedures Using Implanted Lenses

These procedures do not work on the cornea, but on the lens, the other structure in the eye which bends light.

Clear Lens Exchange (CLE)

CLE removes the eye’s natural lens and replaces it with an artificial lens called an intraocular lens (IOL). This is a treatment for cataracts and is also used for presbyopia. Learn more by reading LASIK vs. Clear Lens Exchange (CLE).

Implantable Contact Lenses

A thin lens is implanted in front of the eye’s natural lens to treat severe myopia or hyperopia.

Corneal Implants (Intacs)

Intacs are extremely thin slivers which your eye surgeon implants beneath the cornea’s outer edge. They have the effect of flattening the corneal curvature and are an excellent treatment for mild myopia. They can be removed if you later decide on another course of action.

If you are tired of wearing glasses or contact lenses and would like to have clear vision without them, please visit our Eye Surgeon Directory to find a qualified refractive surgeon in your area.