Posts Tagged ‘correction’
Eyeglasses of all types can be divided into two groups according to the function of their lenses. One main group is prescription eyeglasses, which are equipped with lenses with a power or certain powers. The other basic group is non-prescription eyeglasses. It is absolutely true that there are many ways to categorize the numerous spectacles produced by different manufacturers in the world. But lens power is one of the simplest approaches to such a classification. Eyeglasses in old days were all prescription ones because those wearers resorted to these devices solely for vision correction. Non-prescription eyeglasses are now available and popular in modern days. The emergence of non-prescription spectacles suggests that there are urgent needs from certain individuals to decorate their eyes. This is best testified by the prevalence of fashionable sunglasses. While non-prescription glasses are being enjoyed by more and more people who never need vision correction, prescription eyeglasses are still indispensible for those with defected eyesight.
In general, eyeglass users can buy a pair of prescription eyeglasses only when he or she has gained a valid prescription of the eyes. Such kind of eyeglass prescriptions can be determined by an eye doctor, either an optometrist or an ophthalmologist. An eye optician only has the right to provide eyeglasses according to a prescription given by an eye doctor. This is a strict requirement which is aimed to ensure eye safety for those wearers. In a serious case, an improper or out-of-date prescription may impair the wearer’s eyes. Prescription eyeglasses will help the eyes refocus the entering eyes appropriately, which is called “correction” in brief. But a basis point is that such kind of correction can be precise only when the eyeglass lenses have the right power according to the wearer’s eye condition. In a traditional way, most people trust eye doctors or practitioners when they want to buy prescription eyeglasses due to security concerns. In fact, other sources especially online eyewear stores can also provide safe prescription glasses. They can offer spectacles with vision correction exactly according to the prescriptions submitted by customers.
Dissimilar to prescription eyeglasses, non-prescription spectacles are designed to meet the needs for fashion. Many ordinary individuals and celebrities choose to wear designer sunglasses in summer days. Modern types of non-prescription eyeglasses usually incorporate the cut-edge fashionable tastes. Semi-frame and frameless eyeglasses are both stylish. In addition to special frame styles, non-prescription eyeglasses can also take use of unusual colored lenses. In some cases, those slightly tinted lenses can create an attractive effect. In a word, stylish elements are the key contributor to non-prescription glasses.
Firmoo.com is the emerging online optical store selling high quality eyewear, such as prescription eyeglasses (single vision myopic glasses, reading glasses, bifocal and progressive eyeglasses etc.,), prescription sunglasses (with RX tinted lenses), prescription sports goggles. Firmoo guarantees lowest possible price in the market. Firmoo’s return and refund policy makes any purchase risk-free ones.
Article Source:http://www.articlesbase.com/vision-articles/nonprescription-and-prescription-eyeglasses-1648497.html
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Thanks to continued advances in laser eye surgery, refractive surgery tools and techniques, glasses and contact lenses are fast becoming obsolete for many patients with astigmatism. Patients with undetected astigmatism often experience headaches, fatigue, eyestrain and blurred vision at all distances. Because astigmatism may not be recognized as the cause of these symptoms, this condition may go undiagnosed and continue to affect sufferers. Astigmatism can also be present in children, affecting their ability to see well in school and while playing sports.
Characterized by an irregular curvature of the cornea, astigmatism can be detected by regular eye examinations and successfully treated using procedures such as laser in-situ keratomileusis (LASIK), photorefractive keratectomy (PRK), laser epithelial keratomileusis (LASEK), laser thermokeratoplasy (LTK) and astigmatic keratotomy (AK; Table 1). An ophthalmologist can determine which type of procedure will work best for each patient.
Worldwide, >17 million people have undergone laser refractive surgery, and refractive surgery is one of the most commonly performed operations in the United States and by Beverly Hills LASIK surgeons. The newest laser-assisted procedures are approved by the U.S. Food and Drug Administration to treat up to 6 diopters (D) of astigmatism correction, which includes roughly 98% of all astigmatism patients. Advances in laser technology continue to improve treatment outcomes.
Guttman reported on a recent study by Barraquer, a private practitioner in Colombia, of 364 astigmatic myopic patients treated with a new generation “flying spot” excimer laser. Barraquer reported postoperative best-corrected visual acuity of 20/20 or better in 99% of treated eyes at 3 months. Astigmatic correction was achieved to within ±0.50 D in 92% of eyes.
Remember that for patients in or around Beverly Hills LASIK was used after the detection of astigmatism to treat it in its early and advanced stages. Because children may also have astigmatism, it is important that eye examinations be scheduled at regular intervals to detect any astigmatism early on.
Guttman C. Laser yields safe, predictable correction for astigmatism. Ophthalmology Times, Advanstar Communications, January 1, 2008;36.
Andrew I. Caster, M.D. has performed over fourteen thousand procedures to correct nearsightedness, farsightedness, and astigmatism. Dr. Caster is widely considered one of the most knowledgeable Lasik surgeons in the United States. Los Angeles Magazine selected Dr. caster as “The Best Lasik Surgeon in Los Angeles” and W Magazine listed him as one of two top Lasik surgeons in the United States. For more information please visit: http://www.castervision.com/
Article Source:http://www.articlesbase.com/vision-articles/refractive-surgery-eliminates-glasses-for-many-astigmatic-patients-1597619.html
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If you dream of freedom from glasses or contact lenses laser vision correction may be the solution for you. LASIK is the most well-known vision correction procedure, but there are several other types of laser vision correction. By reshaping your cornea, your ophthalmologist can correct nearsightedness, farsightedness, and astigmatism, giving you clear vision without the hassle of corrective lenses.
Refractive Error
Nearsightedness (myopia), farsightedness (hyperopia), and astigmatism are all forms of refractive error. Your cornea bends, or refracts, light to focus on the retina. When your cornea is misshapen the light does not focus properly. Refractive surgery reshapes your cornea, correcting how the light is bent and therefore correcting the focus of the light on the retina.
Types of Laser Vision Correction
You have probably heard of LASIK, but might not be aware that there are two types of LASIK, traditional and custom, and that there are several other forms of laser vision correction including:
- Epi-LASIK
- iLASIK
- LASEK
- InterLase
- PRK
All are performed using an excimer laser. The technique is different for each type of laser surgery, making laser vision correction possible for people who are not good candidates for LASIK.
The Precision of Today’s Laser Vision Correction
Refractive surgery is not new, but it is being constantly improved. Traditional LASIK has been used to safely and effectively correct vision for over twenty years. Custom LASIK is far more precise, and can give you even clearer vision.
In custom LASIK, Wavefront technology is used to map your eyes and guide the laser. Wavefront is also used to guide other types of laser vision correction. Wavefront diagnosis helps your ophthalmologist determine which type of laser surgery is right for you, and can detect high order aberrations that can be made worse by LASIK surgery.
Improving Your Vision and Your Life
Laser vision correction can mean freedom from corrective lenses for many patients. Those with very poor vision can achieve better corrected vision. Improving your eyesight can open up opportunities that you never had before. It may simply make things like swimming and other hobbies easier and more fun. For some, it can make essential activities, such as driving, possible. Getting rid of your glasses or contacts means waking up each morning with clear vision and never again having to worry about losing or damaging your lenses. To learn more about laser vision correction and what you can do to improve your vision please visit eyes.com today.
To learn more about laser vision correction and what you can do to improve your vision please visit Eyes.com today.
Article Source:http://www.articlesbase.com/vision-articles/laser-vision-correction-1600068.html
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Myopia is commonly known as nearsightedness. It means you have difficulty seeing things that are far away. With myopia you can see clearly up close unless you have another condition that affects your close vision, such as presbiopia or astigmatism. Most myopia begins in childhood, but some factors can cause myopia to develop later in life. In adults, myopia can be corrected with laser eye surgery including LASIK.
Myopia and Your Cornea
Your cornea bends light as it enters your eye. A properly shaped cornea focuses that light on the retina. If you are nearsighted your cornea is either too curved or your eye is too long, causing the light to focus in front of the retina. When the light reaches your retina it has started to spread out again and the image is blurry.
Eyeglasses for nearsightedness have concave lenses. This spreads out the light before it reaches the cornea, so it travels farther back in the eye before it is focused.
Laser vision correction reshapes the cornea so it can focus the light properly on the retina.
What Causes Myopia?
Nearsightedness is the most common of all vision problems and affects about 30% of Americans. In the last few decades it has become more common throughout the world. The causes of myopia are uncertain, and the subject has become quite controversial.
Heredity seems to play a large role. Children of myopic parents are more likely to be nearsighted.
Lifestyle may contribute to myopia, as well. Long periods of close work, such as reading, looking at the computer screen, and possibly even watching television, may affect how a child’s eyeball develops as they grow.
It is also believed that a diet high in simple carbohydrates increases your chance of developing myopia, due to too much insulin circulating in the bloodstream (hyperinsulinemia). Hyperinsulinemia is also common in people with type II diabetes and insulin resistance. Late developing myopia is sometimes an early warning sign of diabetes risk and can eventually develop into cataracts.
Complications of Myopia
For most people myopia is an inconvenience, but relatively harmless and easily corrected with glasses or contact lenses. If corrective lenses are too much of a hassle, laser eye surgery is an option as well.
However, myopia can lead to more serious eye conditions, vision loss, and even blindness. People with myopia have an increased likelihood of developing glaucoma and retinal detachment.
Correcting Myopia
Typically, your eye doctor will prescribe glasses and/or contact lenses to correct your vision. Eye exercises can help improve your vision, especially when eye strain from close tasks such as long hours of computer use is a factor.
Laser vision correction can allow you to see clearly 24/7, without the hassle of wearing glasses or contacts.
If you are nearsighted and would like to learn more about improving your vision, please visit Eyes.com today and find out if you are a candidate for LASIK.
Article Source:http://www.articlesbase.com/vision-articles/myopia-1600072.html