Myopia is a vision problem that has an effect on about one-third of the population. This condition often sets in at childhood and is one that many of your family and friends suffer from everyday. Even I experience it everyday. However, myopia is normally not life-threatening or even hazardous to your health. Myopia is nothing more than nearsightedness.
Myopia occurs because of the shape of the eyeball. Instead of a `normal' shaped eyeball, the myopic eyeball is slightly longer. This results in light rays focusing in front of the retina, instead of directly on it. Because the image is focused directly in front of the retina, objects that are close up appear clear while objects in the distance are blurry.
Myopia is thought by most professionals to be mainly caused by genetics. Donald Mutti, lead author of the study and Ohio State University's associate professor of optometry, conducted a study based on 366 eighth-graders' current prescriptions, their parents' prescriptions and test scores in basic reading language skills. He says myopia follows a dose-dependent pattern. This means that the probability that a child will develop myopia increases significantly based on the number of myopic parents the child has. However, he also says that a child with two myopic parents will not necessarily develop myopia. This shows that this dose-dependent pattern is not a straightforward inheritance pattern.
Others think that the amount of time a child studies and reads has a lesser role in the development of nearsightedness. Interestingly enough, the amount of time that a child watches television and plays video games had little, if any, effect on the development of myopia (H&M WEEK). In fact, the study showed that myopic children studied ...
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...ical condition that can easily be corrected. Whether one chooses a simple solution such as glasses or contact lenses or opts for a more complicated answer such as surgery or implantable contact lenses is entirely up to the individual. Based on what I've researched, I feel that corneal refractory therapy is an easy and reasonably safe way to not only cure the symptoms, but also permanently correct your vision.
Bibliography
Bailey, Gretchyn, and Judith Lee. Myopia or Nearsightedness. 6 May 2003 http://www.allaboutvision.com/conditions/myopia.htm
"Myopia; Genes are main culprit in development of myopia." Health & Medicine Week. 31 Mar. 2003: 3.
"Myopia; Investigator reports 99.4% patient satisfaction for implantable contact lens." Medical Devices & Surgical Technology Week. 18 May 2003: 53.
Seltzer, Jo. "Ophthalmologists Express Skepticism About Vision Therapy." Stlbeacon.org. N.p., 30 Nov. 2010. Web. 1 Mar. 2014.
There are several factors that can increase the risk for developing glaucoma. People over age of 60 and for African-American the risk begins to increase after age of 40. Race is also a factor in developing glaucoma. African Americans are more likely to get glaucoma than Caucasians, and they are also more likely to s...
-Reilly Philip. Is It In Your Genes. Cold Spring Harbor Laboratory Press. 2004: 223-228. Print
According to Baily and Hall, while visual impairment early in life is associated with inherited congenital disorders, abnormal fetal devepment, and problems associated with premature birth, most eye conditions are associated with aging. They claim that over 70% of the visually impaired population in the United States is over 65. Age related maculopathy, also called macular degeneration, or AMD, impairs the center of vision in older individuals. The macula is the region in the back of the retina that surrounds and includes the fovea (Goldstein 1999). It is important to understand that when this degeneration progresses enough, the condition constitutes blindness because the foveal area is what is used to focus on something. Most cases do not progress this far, but between five and 20% do. Allikments and Shroyer claim that 11 million people in the United States alone suffer some degree of this impairment, with 75% of those individuals being 75 or older. Seven percent of this older age group reportedly suffer advanced forms. Freidman reports the disease as most common in developed countries.
When I was 2 years old I was diagnosed with Strabismus or as many know it as ‘Crossed Eyes’. I got my first lovely pair of glasses when I was 3 years old after trying the ordinary patches or special glasses to try and fix the turn of my eyes. Of course being that young, how I looked or the fact that I wore glasses never once effected me or made me feel less of myself. I was a happy kid playing, making friends and enjoying life. When you are so young you shouldn't care that you wear glasses and you shouldnt even when
Lewis, Ricki, (2014), Human Genetics, 11th Edition, Chapter 12. Gene Mutation. [VitalSource Bookshelf Online]. Retrieved from
Myopia is a condition in which visual images come into focus in front of the retina of the eye. This condition causes objects at a distance to appear blurry, while objects nearby are seen clearly. If not severe, myopia can be treated with contacts or glasses. Other treatments for myopia include photoreactive keratectomy (PRK), LASIK, and orthokeratology. Degenerative myopia is a quick progression of myopia and leads to complete loss of vision. The treatment for degenerative myopia is a combination of medication and laser surgery.
The human eye is an organ that allows a person to see, the sense of sight. The eye is composed of several parts including the cornea, lens, pupil, retina, optic nerve etc. There are two portions the eye is broken into, the front third is the anterior segment and the other two thirds is the posterior segment. The anterior segment includes the lens, cornea, iris, and ciliary body. The posterior segment of the eye essentially is the back portion of the eye. In detail, the posterior segment is the portion of the eye behind the lens that includes the retina, macula, optic nerve, choroid, and vitreous humor. There are many diseases that affect the eye and those in particular affecting the posterior segment will be discussed in detail.
Myopia is more commonly referred to as nearsightedness and leaves the person with the ability to see objects that are close up clearly, but those that are far away are out of focus. Hyperopia, in contrast, involves the inability to see objects that are near clearly and is often referred to as farsightedness. Objects that are far away, however, can easily be seen. As humans age, they frequently develop a condition known as presbyopia. This condition decreases the person's ability to focus sharply on those objects which are nearby and is the result of the lens of the eye hardening.
There's a disease that lurks among young children even to this day. It's a direct result of a mutation in the genes that could result in the removal of the eye. Both boys and girls are affected, and one in every fifteen to thirty thousand babies is infected every year (Ambramson, Ch1). This eye corrupting, chromosomal abnormality shows up in about 300-350 new cases each year. It is called retinoblastoma.
The four main components of the eye that are responsible for producing an image are the cornea, lens, ciliary muscles and retina. Incoming light rays first encounter the cornea. The bulging shape of the cornea causes it to refract light similar to a convex lens. Because of the great difference in optical density between the air and the corneal material and because of the shape of the cornea, most of the refraction to incoming light rays takes place here. Light rays then pass through the pupil, and then onto the lens. A small amount of additional refraction takes place here as the light rays are "fine tuned" so that they focus on the retina.
Amblyopia is a condition in which visual acuity in one eye is greatly reduced. It is caused by lack of stimulation or disuse during visual development (Rose, 1998). Because the eye is not fully developed at birth (Jarvis, 1992, as cited in Rose, 1998), infants need stimulation to complete the visual neural pathway. When one or both eyes are inhibited, for example due to misalignment of one eye (strabismus) or a large difference in refractive power between two eyes (anisometropia), the neural pathway for the inhibited eye develops abnormally, or does not develop at all. At approximately six years of age eye development is complete (Stager, 1990, as cited in Rose, 1998). Before visual development is complete amblyopia can be treated. If it is caught and treated at an early age, normal vision can be preserved (Rose, 1998).
Glaucoma is a group of eye disorders that cause blindness by hurting the optic nerve, which is the large nerve that is responsible for vision. In glaucoma, the optic nerve damage is related to a change in the fluid pressure that circulates around the eyeball. In many cases, Glaucoma occurs when the eye's fluid pressure is high, but it can also occur when the pressure is measured as normal.
Macular degeneration also known as late, aged-related maculopathy is an eye disorder which causes a decrease in the visual field known as the retinal macula (Medical Encyclopedia, 2000). The majority of people who are affected are people over the age of 65, but occasionally it develops earlier in people 40-50 years old (Philippi, 2000). The majority of the visual loss is located in the central part of the visual field, while the peripheral vision is unharmed. There are also two types of macular degeneration, the "wet" and "dry" forms. The "dry" form of this disease is the most popular, affecting 90% of the cases (American Academy of Ophthalmology, 1997).
The images formed on the two retinas are so unlike that they cannot be blended in the brain. Thus, a double image is perceived. The condition is known as diplopia, or double vision. Prismatic lenses are prescribed to correct this defect.Imperfections in the cones of the retina, resulting from heredity or disease, cause defective color vision. This is known as color blindness, or Daltonism. In total color blindness, everything appears in shades of gray.