by: Gray Rollins
Refractive eye surgery is a type of eye surgery that is used to rectify refractive errors of the eye and decrease dependency on 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 different procedures exist for refractive eye surgery depending upon the type and severity of the refractive error.
There are four main types of refractive eye surgery procedures: flap and photoablation procedures; corneal incision procedures; thermal procedures; and implants. Currently, the most common refractive eye surgeries involve the use of lasers to reshape the cornea.
Flap procedures involve cutting a small flap in the cornea so that the tissue underneath can be reshaped to correct the refractive error. LASIK, short for Laser Assisted In-Situ Keratomileusis, is the most popular refractive surgery and is used to correct myopia, hyperopia, and astigmatism. The LASIK procedure involves using 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 best suited for individuals with thin or flat corneas. The LASEK procedure uses a small trephine blade to cut into the shallow epithelium, after which the eye is bathed in a mild alcohol solution to soften the edges of the epithelium. The flap is gently 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 create a thin epithelium sheet for removal instead of the harsher blade and alcohol.
Photoablation, the second stage in flap procedures, makes use of ultraviolet radiation to remove excess corneal tissue. PRK, or photorefractive keratectomy, was the original laser eye surgery procedure. PRK involves numbing the eye with local anesthetic eye drops, and reshaping the cornea by destroying miniscule amounts of tissue from the surface of the eye. The laser used, an excimer laser, is a computer-controlled ultraviolet beam of light. It burns cool so as not to heat up and damage the surrounding eye tissue.
Corneal incision procedures such as radial keratotomy and arcuate keratotomy use miniscule incisions 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 incisions in the cornea. The result of the incisions is that the cornea flattens out, minimizing the effects of myopia. Arcuate keratotomy, or AK, is very similar to RK. The diamond knife is used to cut incisions that are parallel to the edge of the cornea, as opposed to the spoke-shaped incisions of the RK procedure. These procedures have been much less common with the emergence of laser-assisted refractive eye surgeries.
Thermal procedures use heat to correct temporarily hyperopic refractive errors, or farsightedness. The thermal keratoplasty procedure involves putting a ring of 8 or 16 small burns on the eye immediately surrounding the pupil. The application of the heat increases the slope of the cornea, making it steeper, through thermal contractions. There are two main types of thermal keratoplasty. Laser Thermal Keratoplasty, or LTK, is a no-touch procedure that uses a holmium laser. Conductive Keratoplasty, or CK, uses a high-frequency electric probe.
The final type of refractive eye surgery involves the use of implants. Implantable contact lenses, or ICL, can be used to correct severe levels of myopia, hyperopia, and astigmatism. The implants are actually tiny contact lenses that are inserted through a small incision in the side of the cornea. Implants are seated so they sit immediately in front of the eye's natural lens just behind the cornea. ICL works in conjunction 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 disadvantages, and not all individuals are suitable candidates for refractive eye surgery. Individuals who are interested in learning more about surgical options should contact their ophthalmologist for more information about these procedures, as well as inquire about other new cutting-edge procedures. Since ophthalmologic surgery is constantly growing and changing with emergence of new technologies and methods, there are always new techniques in development. As new equipment is developed and methods refined that can improve the success and minimize the side effects of refractive eye surgery, new procedures will emerge to replace outdated techniques.
About The Author
Gray Rollins is a featured writer for MyEyeSurgery. To learn more eye sugery visit: http://www.myeyesurgery.com/refractiveeyesurgery/ and http://www.myeyesurgery.com/lasikeyesurgeon/.
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Facts About Colored Contact Lenses
Facts About Colored Contact Lenses
by: Martin Smith
Colored Contact Lenses are the fashion statement of the day. They are available in shades of green, blue, and sometimes lavender. Colored contacts need to be matched to your skin tone for best results.
There are four main types of colored contacts, although there is little difference them.
Visibility tint lenses have a slight tint that will help you locate the lens when it is in your eye easily. This is particularly helpful if the lens should slip out of place.
Enhancement lenses have an obvious tint to change the eye color of the wearer. Change is generally more effective for people with light colored eyes such as blue, hazel, or green.
These lenses are a great way to initiate subtle changes to your eye color.
Opaque color tint lenses are generally used for those who have dark
colored eyes such as such as brown eyes. Opaque color tint contacts have very...
Contact lenses > Facts About Colored Contact Lenses
Unsure About LASIK? Alternatives to LASIK Surgery
Unsure About LASIK? Alternatives to LASIK Surgery
by: Nicola Kennedy
It?s true that LASIK is one of the most prevalent types of eye surgery. However, a few people are either not comfortable with, or not suitable for LASIK surgery due to inadequate thickness of the corneal tissue. There are several alternatives to LASIK surgery, each possessing certain characteristics that make it more appropriate in a particular situation. The procedures may be different, but the key intent is to correct the vision. The following are a few of the major alternatives to LASIK surgery.
LASEK (Laser-Assisted Sub-Epithelial Keratomiluesis) is a recent addition to the refractive surgery catalog. As noted above, the density of the corneal tissue is inadequate in some patients, and hence, LASIK is not a possible option for them. In such a scenario, procedures like LASEK or PRK (Photo-Refractive Keratectomy) can be viable alternatives. These procedures produce the same...
Unsure About LASIK? Alternatives to LASIK Surgery
Contact lenses > Unsure About LASIK? Alternatives to LASIK Surgery
Top of the Line Digital Cameras
Top of the Line Digital Cameras
by: Warren Lynch
If you think that digital cameras are for snapshots only, then you obviously haven't heard about SLR (Single Lens Reflex) digital cameras. SLR is a type of camera which has one lens for composing the frame and capturing the image. SLR cameras are also known as TTL (through-the-lens) cameras.
An SLR camera displays an image through the viewfinder that is exactly the same image as the camera sees and is exactly the same image that the camera is going to record when you release the shutter.
An SLR camera provides a much more accurate image through the viewfinder than a digital camera produces on its LCD because the LCD does not faithfully reproduce the colors and light intensity that is actually entering the camera.
The top of the line SLR digital cameras rival the best film-based SLR cameras and are designed for serious hobbyists and professional photographers. Digital SLR cameras are...
Top of the Line Digital Cameras
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Can A Contact Lens Really Get Lost In Your Brain?
Can A Contact Lens Really Get Lost In Your Brain?
by: Steve Cogger
Did you lose your contact lens under your upper eyelid? HELP!
If you ever get a contact lens misplaced under your upper lid the first step is to stay relaxed. There is never really a reason to panic. Know that it is not at all dangerous to have a lens under your upper lid, usually it does not even hurt. At best it is a nuisance, nothing more.
Also know that your lids are attached to your eye, so the lens can not get lost behind your eye, in your brain, or up in your forehead. Let me repeat that, a contact lens can never get lost behind your eye and go in to your brain. It is impossible and will never happen.
So how do you get a contact lens out from under your upper lid? There are two basic techniques depending on what style of lens you are wearing.
Removing a Soft Contact Lens From Under Your Upper Lid:
1) Look all the way down towards your nose.
...
Can A Contact Lens Really Get Lost In Your Brain?
Contact lenses > Can A Contact Lens Really Get Lost In Your Brain?
seeds What Is Refractive Eye Surgery? Contact lenses
trucks What Is Refractive Eye Surgery? Contact lenses
What Is Refractive Eye Surgery?
What Is Refractive Eye Surgery? skirts Contact lenses
We?re Trying To...........
We?re Trying To...........
by: Graham and Julie
How many times have you heard this in your life. Perhaps you have said it yourself. We are trying to accomplish something here. We are trying to complete this programme. We are trying to change the attitudes of our employees. We are trying to finish so we can go on holiday. We are trying to get fit. We are trying to diet. We are trying to give up smoking/drinking/eating donuts or whatever.
These are all statements...
coffee What Is Refractive Eye Surgery?
Contact lenses > We?re Trying To...........