Refractive surgery

Refractive surgery is a type of eye surgery that is used to improve the refractive state of the eye and decrease or eliminate dependency on glasses or contact lenses. This can include various methods of surgical remodeling of the cornea or cataract surgery. The most common methods today use excimer lasers to reshape the curvature of the cornea.

Types of refractive surgery

Refractive surgery is divided into two main types: corneal-based procedures and lens-based procedures.

Corneal-based procedures

• Photorefractive keratectomy (PRK): This was the first successful laser vision correction procedure used to remove (ablate) tissue directly from the eye's surface to change its curvature.
• Laser-assisted in-situ keratomileusis (LASIK): LASIK is similar to PRK, but a flap is made in the cornea prior to ablating tissue.
• Laser-assisted subepithelial keratectomy (LASEK): LASEK is a modification of PRK, intended to reduce the recovery time and improve comfort.
• Epithelial laser-assisted in-situ keratomileusis (epi-LASIK): In this variant of LASIK, a thin flap of epithelium is created using a microkeratome or a femtosecond laser, then moved aside prior to ablation with an excimer laser.

Lens-based procedures

• Phakic intraocular lens (PIOL): The phakic intraocular lens is a lens implant that is placed inside the eye without removing the eye's natural lens. The PIOL increases the eye's total optical power to correct myopia (nearsightedness).
• Refractive lens exchange (RLE): Also known as clear lens extraction (CLE), this is a procedure where the eye's natural lens is replaced with an artificial one.

Risks and complications

Like any surgery, refractive surgery carries potential risks and complications. These can include undercorrections, overcorrections, developing a haze on the cornea, halos or starbursts around lights, dry eyes, and loss of vision.

See also

• Ophthalmology
• Optometry
• Visual acuity

References

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  Refractive surgery
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  Refractive surgery