Thursday, June 30, 2011


The first post I would like to focus on is Myopia because this is extremely common with many individuals. Myopia is another word for nearsightedness and over seventy million Americans are affected by this, including myself and my family. Nearsightnedness is the inability to see distant objects clearly, which affects people of all ages from young to older adults.

A little atnatomy of the eye: Images are formed on the retina by a team effert of the cornea, iris, pupil, and the lens. Through this "team" the eye is able to bend light rays so that they focus directly on the retina. From there there the visual information can then be translated into nerve impulses for it to be sent to the visual cortex of the brain. Which means the light enters the eye and then is refracted towards the back of the eye. The eye is very much like a camera, which means that it is designed to take the best possible picture of the world!

The first part of the eye that the light touches is the cornea. The cornea is what bends the light rays as they pass through it. The cornea accounts for about eighty percent of the eye's focusing power. The pupil and iris work together to control the amount of light that enters the eye. Behind the iris and pupil is the lens. This is an elastic structure that becomes thinner to focus on distant objects and thicker to focus on nearby objects. Our ability to see correctly primarily depends on the lens's ability to focus light directly on the retina in the back of the eye. This process is called accommodation.

Now that we have a brief description on how the structure of the eye works, myopia is a very common imperfection of an individual's vision. Have you ever sat in a classroom and find yourself unable to make out any words on the chalk board until a few feet away?

If so, there is a huge possibility that you're experiencing the same imperfection of your vision, which is myopia.

With myopia, parallel rays of light goes into focus at a point in front of the retina where the image reaching the retina is blurred. The eye might possibly be too long (refractive myopia) or the cornea has too much bend (axial myopia). Myopia does run in families and usually appears in childhood. Due to the eye continuing to grow during childhood, myopia generally develops before the age of twenty.

The solution to this problem is well known to many people suffering from this condition. The eye doctor will prescribe glasses or contacts to the individual. These corrective lenses bend incoming light so that it is focused as if it were at the far point.

Surgical procedures have also been helpful for this problem. More than one million Americans had laser-assisted in situ keratomileusis (LASIK) surgery. This involves sculpting the cornea with a laser called "excimer laser". A small flap is cut into the surface of the cornea, then the flap is folded out of the way so that the cornea can be sculpted. This procedure has been very successful with people able to see distance without glasses or contacts. I have personally looked into this procedure, but it is not recommended to have at a young age because the older you get, the more your eye changes. It is recommended to receive this surgery when you are at least well into your forties and up.

1 comment:

  1. I found this section interesting mainly because, like many people,I have this condition. I didn't know the science behind it, I just knew I needed glasses. Moreover, while I knew the term "nearsighted", I'd never heard of "myopia" before. When visiting the optometrist and undergoing eye exams, the reasons behind the condition are/were not really explained, at least they weren't to me. It's pretty interesting to now have insight into this condition.