Posts Tagged ‘Myopia’

Brief introduction of presbyopia

December 7th, 2009

The origin of the word “presbyopia” is two Greek words “presbys” and “opia”, which mean “old man” and “eye”, respectively. So presbyopia is also called elder eye, and it is an eye problem where the eyes are not able to focus on near objects. For examples, people have difficulty in reading newspapers or other fine print, especially in low light condition. Presbyopia is a symptom caused by the natural course of aging, and it is very common among elders. Presbyopia usually first occurred between the ages of 40 to 50. The mechanisms of presbyopia have not been known exactly. It may be caused by a loss of elasticity of the crystalline lens or the changes in the lens’s curvature from continual growth and loss of power of the ciliary muscles.

Similar to another kind of eye problem called myopia (nearsightedness), presbyopia can be corrected by eye glasses or contact lenses. Because it is considered as a part of the human aging process, just like grey hair or death, presbyopia is not routinely curable. However, people with presbyopia can choose surgical procedures, including IOLs.

Presbyopia is the opposite condition of myopia. So people with myopia are usually able to read without eyeglasses or contact lenses even after age 40, although their nearsightedness may not disappear. This is the payoff of nearsightedness. Due to the disadvantage of being presbyopic after age of 40, refractive surgery for correcting myopia are not suggested. Because people with refractive surgery may become presbyopia, and they need to use glasses for reading.

About Myopia

November 18th, 2009

You may be unfortunately one suffering from myopia, however, do you know how myopia occurs. Generally speaking, there are two main reasons for the formation of myopia. The first one is the hereditary factor. Researches reveal that if parents are both nearsighted, their children have a 33% chance to develop into myopia, which normally tends to show up when children get their 8 to 12. The second one should be the environmental factor. If you spend most of your time on close work, such as watching TV, and working before a computer, etc., you will probably develop into nearsightedness. Close work will also aggravate condition if you’ve already have a myopia. However, what makes things strange is that some people will not get shortsighted even if they often do close works. This is what researchers are exploring.

In theory, myopia occurs when eyes are larger than normal eyes in size. Thus, bigger and elongated, eyes project the light rays from faraway objects to a mid point of the eye but not onto the retina. Such images often come to be blurry. This is the so called refractive error in the eye. The roles eyeglasses and contact lenses perform in nearsightedness is to help make image project to the place, that is the retina, where they suppose to be, in which way image come back to be clear.

Apart from blurry vision, nearsighted person would often suffer from other symptoms, such as burning or tired eyes, headaches and restricted tolerance to reading. Similarly, when someone sits closely to the television to enjoy programs, he is not surely myopic but maybe his or her specific interest or habit. Moreover, a middle aged person who suddenly finds things become fuzzy in vision is also not sure to be myopic. He is more probably recognized as an early symptom of cataracts which is a common eye problem for the middle aged. What is more, it also can be an indication of keratoconus, which would make the cornea of the eye change shape and may be a inducement of diabetes. Therefore the best way to know whether you are nearsighted or not is to have an eye check in doctor’s office.

Myopia is not a must procedure one will suffer from in his or her life. If you are not a nearsighted person, spend more of your time out in the fresh air. A study shows that those who do so often are less likely to get myopic than those who spend most of their time on close work; if you are a nearsighted person, there are also effective treatments. Besides wearing eyeglasses and contact lenses, eye surgical corrections are another options which are more preferable, among which LASIK is doable. Lasik, or say PRK (Photo Refractive Keratectomy) is a kind of eye surgery which is accomplished by removing a small piece of tissue prior to the flap being reattached. In this way the eyes can focus objects on the retina again. However, in view that each surgery is a big step for everyone, therefore to consult related information in details and take side effect into consideration is necessary.

Anyhow, no matter whether you are shortsighted or not, and if you are, no matter what kind of treatment you are going to take, it is important to have frequent eyes examinations. It is suggested to test eyes for any changes on an annual basis as for children and to test every two or three years as for adults.