Refractive surgery
In a world where we use a “Kleenex®” regardless of the type of “facial tissue” we have, and make a “Xerox®” no matter what brand of “photocopier” we use, it is no surprise that many people think you get “LASIK surgery” regardless of what kind of “refractive surgery” you actually undergo. To help you understand the various types of refractive surgery, we define some of the more common techniques here.
Astigmatic keratotomy
One type of keratotomy procedure. Astigmatic keratotomy (AK) treats astigmatism. The surgeon cuts the cornea in areas that are too bulgy, flattening them to a more regular curve.
Conductive Kerotoplasty (CK)
Used to treat farsightedness and presbyopia, CK shrinks tissue to reshape the cornea. With this procedure, the surgeon uses a radio frequency probe instead of a laser. No cutting or tissue removal is necessary. The procedure takes about three minutes.
Corneal implants
A surgical option for correcting nearsightedness that doesn’t involve lasers. Corneal implants use two clear pieces of a plastic polymer that are inserted into the cornea. These implants are designed for long-term vision correction.
Hexagonal keratotomy
A type of keratotomy procedure no longer used by eye surgeons. At one time, hexagonal keratotomy (HK) was performed to treat farsightedness. Surgeons no longer perform this type of procedure due to the high incidence of complications.
Keratotomy
A procedure in which the eye surgeon cuts the cornea to change its shape, reducing a refractive error. Depending on the refractive error, patients may undergo radial or astigmatic keratotomy. A third type of keratotomy, hexagonal keratotomy, is no longer practiced.
LASIK
Laser-assisted in situ keratomileusis (LASIK) treats nearsightedness, farsightedness and astigmatism. The surgeon cuts a flap in the stroma, then uses an excimer laser to remove material under the flap. LASIK usually takes less than one minute per eye.
LASEK
Laser epithelial keratomileusis (LASEK) is similar to LASIK, except that the eye surgeon cuts a flap in the epithelium only, instead of through the epithelium and part of the stroma. LASEK is used most often for patients with thin or flat corneas who are poor candidates for LASIK, which requires more corneal tissue.
PRK
Photorefractive keratectomy (PRK) is surgery to treat nearsightedness, mild to moderate farsightedness and astigmatism. The surgeon uses an excimer laser to remove tissue from the cornea surface. This removal (or ablation) results in a new shape, thus reducing the vision problem.
Radial keratotomy
One type of keratotomy procedure. Radial keratotomy (RK) treats mild to moderate nearsightedness. A surgeon makes incisions in a radial (spoke-like) pattern in the cornea, causing it to flatten and reduce nearsightedness.
Refractive surgery
The broad term for surgery that corrects vision, with the objective of reducing or eliminating the need for glasses and contacts. Types of refractive surgery include radial keratotomy, PRK, LASIK and corneal implants.
Verisys Phakic IOL
An intraocular lens implant for patients with a high degree of nearsightedness who are not LASIK candidates. Available for prescriptions from -5.00 to -20.00.
For more information, visit Park Nicollet's Refractive Surgery Web site.
