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What is Wave-Front Technology and is it an Improvement?
When the Hubble telescope was sent into space, NASA wanted the best pictures ever. The optical engineers "re-invented optics"; they learned that there was more than just correcting simple focusing errors such as myopia (nearsightness), hyperopia (farsightness) and astigmatism. They corrected "higher order optical aberrations". In English this means that they corrected small errors which nobody thought made a difference. Specifically, these small errors caused ghosting and glare which was often associated with LASIK procedures. These small errors become more important when the optical error is large (-6.00 and more) and when the pupils are big.
Correction of these fine errors requires specialized instruments that measure wave fronts of light. Wave front measurements are more accurate but they have a downside. Wave front technology with custom corneal ablation (shaping) removes more corneal tissue. Sometimes, this results in a cornea that is too thin. Most patients will not perceive the difference between wave front and non-wave front guided LASIK. Ask anyone who has already had LASIK, they will tell you how thrilled they are.
I Have Heard That "All Laser LASIK" is Better than When the Flap is Made With A Blade; Is It True?
First of all there is no evidence that the results are better with Intralase laser making the flap. On the contrary, patients who have the flap made by by a laser experience more pain, have poorer vision on the first and second day post-op, and have a higher incidence of an inflammatory reaction called DLK. In addition, Intralase adds another $300 to the cost of LASIK without any real benefit, except marketing.
How About Conductive Keratoplasty to Eliminate the Meed for Glasses?
Conductive keratoplasty (CK) uses a tiny probe to apply radio waves in a ring-like pattern on the cornea; which heats up the collagen in the periphery of the cornea. The collagen shrinks, which acts like a tightened belt around the cornea, this steepens the corneal cureve making it optically more powerful. This corrects hyperopia or if done in one eye reading (monovision). Approximately, 85% can be successfully treated. What about the other 15%. The results in our experience are not as good as reported in the New York Times. Before having CK, one must make sure that the procedure will probably work - i.e. a trial fitting with mono-vision contact lenses.
Make an appointment to see if you are a candidate.
What Can Be Done If My Cornea is Too Thin or If I Have a High Refractive Error?
Photorefractive Keratectomy (PRK) was invented in the early '80s and approved by the FDA in 1995. The procedure was practiced in other countries for years with many Americans going to Canada before it was approved in the U.S. PRK is performed with an excimer laser just like LASIK except there is no flap. The laser removes tissue from the surface of the cornea altering the shape of the cornea to correct the refractive error. PRK usually takes less than a minute per eye. Both myopia and hyperopia can be corrected with PRK. With myopia the procedure flattens the; with hyperopia the laser is used to steepen the cornea. PRK, can correct also correct astigmatism. PRK fell out of favor with advent of the almost painless LASIK procedure. It has been replaced with the newer more comfortable and predictiable LASEK and/or Epi-LASIK procedures.
LASEK (laser epithelial keratomileusis), epithelial LASIK and E-LASIK, which all the same procedure, is a relatively new procedure that is a variation of PRK. LASEK is used most commonly for people with corneas that are too thin or too flat for LASIK. It was developed to reduce the chance of complications that are associated with a flap created by LASIK, e.g. a cornea which is too thin. In LASEK, the epithelium, or outer layer of the cornea, is cut with a fine blade similar to a cookie cutter called a trephine. Afterwards, the surgeon covers the trephined section with an alcohol solution for approximately 30 seconds. The solution loosens the epithelium so that the surgeon can lift the edge of the epithelial flap and fold it back out of the way. Then the an excimer laser is used to sculpt the corneal tissue underneath. Lastly, the epithelial flap is placed back on the eye and smoothed down.
The flap edge heals in about a day, though patients usually wear a bandage contact lens for around four days. Most likely you will feel eye irritation during the first day or two. Vision may not recover for four to seven days. Of course, it varies from one person to the next.
Epi-LASIK is similiar to LASIK - an epikeratome is used to separate the outer layer of the cornea known as the epithelium. Since alcohol is not used, patients usually report less pain than with LASEK and tend to heal faster.
Keratotomy is a procedure in which a scapel is used to cut the cornea which alters its curvature, thus reducing a refractive error.
Radial Keratotomy (RK) is an older technique, not used very often today, to treat nearsightedness. Corneal incisions in a radial (spoke-like) pattern are made to flatten the cornea which reduces nearsightedness. Scars occur which weaken the cornea often resulting in fluctuations in vision and ghosting.
Astigmatic Keratotomy (AK) is similar to RK except only a couple of cuts are made in the periphery of the cornea to reduce astigmatism. AK is usually used as a adjunct to other surgery, i.e. in patients with excessive astigmatism that can not be fully corrected with LASIK, or cataract patients to reduce astigmatism after cataract surgery. It does not present with the problems associated with RK.
Besides Laser Are There Other Methods to Correct My Refractive Error?
Good News - for patients with thin corneas or myopia over -12.00 - there are new ways to correct your refractive error. Lens implants can be used to eliminate near-sightness. A lens implant similar to what is used in cataract surgery is inserted between the cornea and iris. Currently, there are three major designs (Staar Surgical Implantable Contact Lens, Nuvita, and the Ophtec Artisan Lens). We have had the greatest success with the Artisan Lens. The advantage is that they can be removed, do not effect the focusing system of the eye, they do not cause thinning of the cornea, and they are not contra-indicated in patients who have or might have glaucoma.
For patients under -6.00 sphere and -1.75 astigmatism there is a new procedure to reshape the corneal surface without surgery. This procedure uses a contact lens to reshape the cornea while you sleep. Learn more about Corneal Refractive Therapy.
Our doctors and staff have received extensive training in laser refractive correction, reducing the risk of complications. Our expertise lets us help patients should they ever experience any difficulty with their procedure or recovery. Our laser center is staffed with well-trained technicians using the lasers that are calibrated before each procedure. Temperature and humidity are maintained at exact specifications. Our commitment to patient care means that we will always do our best for you before, during and after your procedure.
We stand behind your distance vision results for life because we have confidence in our staff and in the stability of our patients' outcomes over the long-term. While we cannot guarantee that patients will have perfect distance vision for a lifetime, our office will do everything we can to help you maintain your best possible distance vision for life. You will receive free re-treatments when advisable. Hyperopic patients are not covered by this lifetime re-treatment program, but they are eligible for enhancements at no charge within 24 months of their initial procedure. Most myopic and astigmatic patients qualify for lifetime re-treatment program. To retain eligibility, you must simply return to our office each year for an annual exam. (This examination is not included in your surgical fee.) You are eligible for the lifetime re-treatment program if you are in good general health, have myopia and/or astigmatism, and a pre-operative prescription equal or less than the spherical equivalent of -10.00 diopters, and/or astigmatism of no greater than -3.00 diopters. Ninety-nine percent of the myopic and/or astigmatic population falls into this and the patients who are not within these criteria remain eligible for enhancements at no charge within 24 months of their initial procedure.
For a more conservative view read the FDA's evaluation of LASIK.