The LASIK surgeries which are directed toward correcting astigmatisms and nearsightedness fall into three classifications. They are corneal incisions, flap procedures, and photablation.

Corneal Procedures

The corneal incision procedure, sometimes referred to as a keratotomy, is appropriate in cases of misshapen corneas interfering with optical refraction. Poor refraction mean poor eyesight, and LASIK eye surgery which reshapes the cornea will improve refraction. Within the corneal incision family are three slightly different approaches to LASIK eye surgery.

For those suffering from astigmatism, astigmatic keratotomy, or AK, entails the surgeon cutting and then smoothing bulges in the cornea to produce a curve which allows better refraction.

In mild cases of myopia, or nearsightedness, the LASIK eye surgery procedure radial keratotomy, or RK, is the treatment of choice. This technique surrounds the cornea with a spoke-like arrangement of incisions, causing it to flatten. RA is slowly being supplanted by more advanced techniques.

At one time, heaxagonal keratotomy, or HA, was the LASIK eye surgery used to correct farsightedness, but its adverse side effects were so pronounced that it has been nearly eliminated as an option.

Flap Procedures

LASIK actually gets its name from one of the flap procedures, the Laser-assisted In-situ Keratomileusis. In this procedure, the surgeon cuts a flap through the epithelium and into the stroma of the eye, and uses an excimer laser to remove any material which might be responsible for the patient's vision problems.

Epi-LASIK surgery is similar to LASIK eye surgery, except that the flap the surgeon cuts does not go deeper than the epithelium. Because this procedure requires the use of neither a blade not alcohol, the recovery period is both less painful and shorter.

LASEK surgery, while it to only cuts a flap in the epithelium, loosens the flap with alcohol and therefore is slightly more painful, and requires a longer healing period, than epi-LASIK surgery. But it is an ideal option for those not qualified for LASIK eye surgery. For more info see http://www.2020lasikeyesurgery.com/Articles/Lasik.php on Lasik.

Automated lamellar keratoplasty, while it has traditionally been the LASIK eye surgery performed on those with either hyperopia or myopia, is rapidly becoming obsolete. This procedure, which usually lasts an hour, also creates a flap in the stroma.

Photoablation

Photoreactive keratectomy is the most common of the photoablation LASIK eye surgery procedures. PRK is the step in LASIK and LASEK surgeries during which the surgeon uses UV radiation to remove damaged or useless tissue from the eye and reshapes the cornea with an excimer laser. PKA, which takes very little time, can be used to treat astigmatism, and near and farsightedness.