In a previous post, I defined farsighted vs. nearsighted, talked about vision screenings vs. comprehensive eye examinations and touched upon why children are more susceptible to developing nearsightedness (myopia). Let us now delve deeper into “why” myopia can be harmful.
Your Child’s Eyes
You take your child to the eye doctor for a comprehensive eye examination. The optometrist says, “Your child’s eyes have steadily gotten worse over the past three years.” As a parent, your first thought may be, “Oh no! My child has to wear thicker eyeglasses!” You might start worrying about how other children might pick on your son because of these thicker glasses. In either case, I’m here to tell you that your child’s wearing thicker glasses should be the least of your worries. … a greater danger is lurking.
Myopia Changes the Eyes
Inside the eye lies one of the most unique designs in the human anatomy. A matrix of blood vessels and nerves and a focusing mechanism all work together to transform light energy into electrical impulses that travel to the brain. The end result is what we call vision.
In most cases of myopia, the eye elongates horizontally, resulting in a shape similar to that of an egg. The outer coating of the eye (sclera) is where most of these changes occur. The remaining structures under the sclera — retina and choroid — do not stretch or elongate quite as much as the sclera.
When the sclera elongates in one direction but the retina and choroid do not, a separation of these eye structures often occurs. When this happens, the separation often results in a retinal detachment, most often seen in eyes with high levels of nearsightedness (myopia).
Now, let us look at another way increasing myopia affects the eye.
You may have learned in school that the eye is filled with fluid. This fluid, called the aqueous humor, is created inside the eye and keeps the eye healthy. This fluid also must drain from the eye to maintain proper eye pressure.
With high levels of nearsightedness, the outward flow is impeded due to structural changes in the front part of the eye. When this occurs, the pressure inside the eye increases because the fluid cannot drain out of the eye or drains out at a lower rate than normal. Many structures inside the eye are susceptible to damage caused by high levels of eye pressure, most notably, the optic nerve (see picture above). Very high eye pressure correlates strongly with optic nerve damage, which is often called glaucoma.
Unfortunately, it takes more than a few blogs to cover all the intricacies of progressive myopia and its detrimental effects on the eye. In this post, I wanted to cover two of the biggest concerns just to give you a better understanding of why there is a concern in the first place.
The most important thing I would like readers to take away from this blog post is that myopia progression, especially at an early age, can significantly increase the chances of life-long debilitated vision, not to mention the reduced quality of life, increased medical costs and more expensive eyewear purchases.
In the next blog, I will turn the tides of this discussion to give you a few good waves to surf as I introduce to you a few exciting methods that show significant promise in slowing down nearsighted progression and, therefore, in protecting your child’s eyes.
Talk to you soon.