Many people confuse presbyopia with hyperopia. The two symptoms may be thought to be the same, but the causes that occur are different and the way they are corrected is different. Today, I will explain myopia, hyperopia and presbyopia easily and briefly.
What is myopia?
Myopia, astigmatism, and hyperopia are refractive error. A person with myopia is near-sighted who sees a nearby object clearly and does not see a distant object. When light enters the eye and forms an image, the image is formed in the front of the retina, so it looks cloudy. So myopia wears glasses using concave lenses that spread light. If your eye size is larger than average, you are more likely to have myopia
What is hyperopia?
The eyes with hyperopia can see distant objects well. Hyperopia has a small eyeball or flat cornea, so the image forms behind the retina. These eyes are not diagnosed as hyperopia if you take an eye test from an early age.
Children have smaller eyes than adults. Then, because the eyeball grows bigger in the growth period, all children are in hyperopia at first, but when the eyeball grows and the image is formed on the retina, it becomes regular, and if the eyeball size grows a lot, it changes to myopia. You have been hyperopia since you were young, and if your eyes don’t grow much even in your growth period, you will still be hyperopia when you get older. In addition, if the cornea is not convex and flat, it cannot refract light appropriately, so it becomes hyperopia regardless of age.
Eyes with hyperopia are not a big problem because they can see from afar and closely by applying force to the len zonule. However, if the zonule is weakened with age and is not well controlled, you will not be able to see close range, so you will wear glasses that we commonly call reading-glasses. When you wear convex lenses, the surroundings look enlarged, but there is an inconvenience of narrowing your vision.
Even if you get older, people with hyperopia usually have less eye growth, so there are many people with shorter eye lengths. In this case, not only the eyeball length is short, but the space inside the eyeball is narrow, making it difficult to perform cataract surgery. Therefore, it is advantageous for these people to diagnose and treat cataracts early.
What is presbyopia?
As we get older, the lens of our eyes naturally loses elasticity and loses strength. The presbyopia is a type of aging, so both eyes with hyperopia and myopia occur. When presbyopia comes to a person with nearsighted eyes, you can see far away when wearing glasses, but you can’t see close to them, so you have to take off your glasses. Eyes with hyperopia are still visible far away, but they can’t see close, so you have to write and see reading-glasses.
When presbyopia comes, the damage is greater in hyperopia than in myopia. If you are shortsighted, it may not be very uncomfortable to change the prescription of your glasses and wear multifocal glasses because you have been wearing glasses. However, people who are hyperopia often don’t wear glasses until they get presbyopia, but they have to wear glasses because they can’t see the writing on their smartphone because of presbyopia, but it can be very uncomfortable to wear glasses for the first time in their 40s.
Today, we learned about myopia, hyperopia, and presbyopia. Then I’ll come back with an easy-to-understand eyeball common sense next time.
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