Good vision such as 20/20 does not mean satisfying contrast sensitivity. Common vision tests using black letters or numbers displayed against white backgrounds can not reflect your exact contrast sensitivity, since the real world is filled with grey shades. So that special contrast sensitivity testing is necessary.
May eye diseases or conditions may cause poor contrast sensitivity, such as cataracts, glaucoma, and diabetic retinopathy, as well as the side effects from LASIK and PRK. People with low contrast sensitivity may have difficulty in some conditions, such as seeing traffic lights, spot other cars and pedestrians during night driving. Since these people have poor perception of objects that do not stand out from their backgrounds, they may even stumble when they fail to see similarly colored pavements.
The term “contrast sensitivity function” (CSF) is used to describe people’s low contrast seeing ability. A contrast sensitivity test may be included in a routine screening after the visual acuity test, which measures the ability of seeing detailed letters or numbers. With your plastic eyeglasses or contacts lenses wearing on, your eyes will be tested in together by a low-contrast test chart, which consists of bars and dots in different colored contrasts that are used to evaluate the patient’s exact CSF. Your CSF will certainly be affected by the sizes of objects: the larger the objects are, the higher CSF you can achieve.
By testing your eyes using bar and dot patterns displayed against varying contacts or intensities, your highest and lowest contrast sensitivity can be determined and plotted into a curve, which shows your contrast sensitivity readings. Tests under both bright and dark conditions can provide more detailed information about your images process capability.
As a volunteer, you can get a contrast sensitivity test as a necessary part of the evaluation of new ophthalmic devices such as LASIK excimer lasers and new intraocular lenses required by FDA. Once you are diagnosed with low contrast sensitivity, some remedies are available, depending on the source of the problem. Usually, artificial lenses with a yellow filter can improve contrast. If the low contrast sensitivity is caused by higher-order aberrations, wavefront lenses or LASIK are the right choices. Another option is intraocular lenses with yellow tints, which can also offset low contrast sensitivity.
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Your eyes are one of your most important senses. Communicating a wealth of information to your brain, you rely on them to perform a number of essential tasks, like detecting danger and finding sustenance. However, according to research, nearly two thirds of the UK adult population wears glasses or contact lenses. Not only that, but by the time people reach their 60s, 90 percent will require some form of corrective vision.
Making the most of your eyes by looking after them properly, therefore, is of utmost importance. Regular eye tests from a young age are vital and will significantly help to track any changes in your vision, as well as identify problems like short- or long-sightedness early on. Additionally, eye examinations can detect a wide range of other issues, such as diabetes and high blood pressure.
Thanks to advancements in technology, many people who experience vision problems now have the option to permanently correct their eyesight, thus removing the need to wear glasses or contact lenses. In fact, utilising the latest laser technologies, a number of treatments have sprung up in the last few years, which are serving to help millions of people correct their sight.
Having been carried out on more than 22 million individuals worldwide, LASIK (Laser-Assisted-In-Situ-Keratomileusis) is the most common form of eye surgery available. Helping to improve many cases of short- and long-sightedness, as well as astigmatism, it is a relatively non-invasive treatment lasting for approximately 10 minutes.
Using an excimer laser, the optician can reshape the surface of the eye, or if required, both eyes at the same time. More often than not, people notice a significant improvement in their vision just a few hours after the procedure and can usually return to work or drive again after 48 hours.
In comparison to other forms of eye surgery, many patients report experiencing less discomfort after the LASIK procedure has been carried out. Additionally, because it does not remove the epithelium, like LASEK (Laser-Assisted-Epithelia-Keratomileusis) surgery, for example, the eye heals a lot more naturally.
Before the treatment is carried out, you will need to find a reputable optician and schedule a consultation. The internet provides a wealth of information on the subject and a quick search will see you find a range of facts on the procedure, as well as a number of different opticians. After that, you can then discuss with your eye care specialist whether or not the surgery is right for you.
The health of your eyes is crucial. Consequently, it is important to make sure that you care for them properly. However, if you do experience difficulties with your sight, there are many things that can be done to help it, such as LASIK eye surgery. As a result, you can then focus on the more fun things in life.
Adam Singleton writes for a digital marketing agency. This article has been commissioned by a client of said agency. This article is not designed to promote, but should be considered professional content.
Article Source:http://www.articlesbase.com/vision-articles/proper-eye-care-essential-for-healthy-sight-1402175.html