Refractive Eye Surgery
Refractive eye surgery is a sort of eye surgery that is used to rectify refractive blunders of the eye and decrease dependency corrective lenses such as eyeglasses and contact lenses. Successful refractive procedures can reduce myopia or nearsightedness, hyperopia or farsightedness, and astigmatism or elongated corneas. A number of difference procedures exist for refractive eye surgery relying on the type and seriousness of the refractive blunder.
There are four main kinds of refractive eye surgery procedures : flap and photoablation procedures, and corneal incision procedures, thermal procedures, and implants.
The most common refractive eye surgeries involve the utilization of laser to reshape the cornea.
Flap procedures involves cutting a tiny flap in the cornea so that the tissue underneath can be reshaped to correct the refractive error. LASIK, short for Laser helped In-Situ Keratomileusis is the hottest refractive surgery and is used to correct myopia, hyperopia, and astigmatism. The LASIK process involves the use of a microkeratome or IntraLase to cut a flap into the stroma, moving the flap out of the way, removing excess corneal tissue with an excimer laser, then replacing and smoothing out the flap. LASEK is most fitted for individual with thin or flat corneas.
The LASEK process uses a small trephine blade to chop into the shallow epithelium, after which the eye is washed in mild alcohol solution to melt the sides of the epithelium. The flap is delicately moved out of the way so that an excimer laser can remove excess corneal tissue, after which the flap is replaced and smoothed out. Epi-LASIK, like LASEK, involves a shallow cut into the epithelium, but makes use of epikeratome to form a thin epithelium sheet for removal rather than the harsher blade and alcohol.
Photoablation, the second stage in flap procedures, employ ultraviolet radiation to remove excess corneal tissue. PRK, or photorefractive keratectomy ( PRK ), was the original laser eye surgery process. PRK involves numbing the eye with local pain-killer eye drops, and reshaping the cornea by destroying miniscule amounts of tissue from the skin of the eye. The laser used, an excimer laser, is a computer-controlled ultraviolet beam of light. It burns cool so as not to warm up and damage the encircling eye tissue.
Corneal incision procedures such as radial keratotomy and arcuate keratotomy use small cuts in the cornea to alter its surface and correct refractive errors. Radial keratotomy, or RK, uses a diamond tipped knife to make a number of spoke-shaped cuts in the cornea. The results of the cuts is the cornea flattens out, minimizing the consequences of myopia. Arcuate keratotomy, or AK, is very like RK. The diamond knife, though, is used to cut cuts that are parallel to the edge of the cornea, as opposed to the spoke-shaped cuts of the RK process. These procedures have been far less common with the rise of laser-assisted refractive eye surgeries.
Thermal procedures use heat to correct temporarily hyperopic refractive blunders, or farsightedness. The thermal keratoplasty procedure involves puts a small ring of 8 or 16 small burns on the eye straight away surrounding the pupil. The appliance of the heat increases the slope of the cornea, making it steeper, thru thermal contractions. There are two main types of thermal keratoplasty. Laser Thermal Keratoplasty, or LTK, is a no-touch process that uses a holmium laser. Conductive Keratoplasty, or CK, uses a high-frequency electrical probe.
The final type of refractive eye surgery, involves the use of implants. Implantable contact lenses, or ICL, can be used for to correct severe levels of myopia, hyperopia, and astigmatism. The implants are actually tiny contact lenses that are inserted thru a tiny incision in the side of the cornea. Implants are seated so that they sit straight away in front of the eye’s natural lens, just behind the cornea. ICL works in association with the eye’s natural lens to refocus light on the retina and produce a crystal clear image.
Each of these procedures has its advantages and drawbacks, and not all individuals are acceptable applicants for refractive eye surgery. Individuals who have an interest in learning more about surgical options should contact their ophthalmologist for more information about these procedures, as well as ask after other new state of the art procedures. Since ophthalmologic surgery is constantly growing and changing with emergence of new technologies and methods, there are always new methods in development. As new kit is developed and strategies refined that can improve the success and minimize the side effects of refractive eye surgery, new procedures will appear to replace outdated strategies.
