Farsightedness Is To See Far Clear See Near Not Clear Be Presbyopia
Hear the farsightedness, the vast majority think is to see far clear see near not clear, but in fact is not.Normal emmetropia is the eye that sees far and near clearly. Parallel light rays enter the eye and focus on the retina to form a clear image.In farsightedness, parallel light enters the eye and is not focused on the retina, but after it is focused on the retina, the light needs to be focused on the retina with the help of a convex lens, so as to see a clear image.In popular terms, farsightedness actually means that you can't see far or near clearly.
Why are people farsighted?
The vast majority of myopia is because the eyeball is small, the diameter before and after the eye is short, the eye axis that is said on medicine is short.This eyeball is small and we usually say small eyes are not the same, we usually say small eyes big eyes actually refers to the fissure between the upper and lower eyelid (medically called palpebral fissure) size, part of the small eyeball people palpebral fissure is small, but there is no corresponding relationship between the two.Just like the height of the human head, the axis of the eye also has the length of the points, especially short eyeballs, known as small eyeballs in medicine.Small eyeballs show hyperopia or even high hyperopia.
People grow up, stature gradually grow tall, eyes also have a process of growing up, early life, everyone is farsighted.Eyeball was born hard long, about 8 years old to complete the process of emmetropization.So the child vision development also has a process.
So, does everyone become optical-eyed by the age of eight?Not, still have many people eyeball slant small, be in farsightedness state, need to wear convex lens ability to see clearly, some people still cause strabismus because of farsightedness possibly.
Some people have farsightedness, but they can use the ciliary muscle to focus and get clear vision.Such a situation, belong to recessive hyperopia.To see far eyes in a relaxed state, not tired, just see nearly ciliary muscle when you need to focus, and far-sighted, watching far ciliary muscle requires focus, watching nearly ciliary muscle to pay more efforts, make a simple example, face to see things, b and ciliary muscle, often have a rest, and farsighted see things, ciliary muscle has been run, so it's easy to visual fatigue.In patients with farsightedness, not only visual fatigue, but also eye pain, swelling of the eyebrow arch, headache, insomnia, memory loss and other regulatory fatigue symptoms may occur.
Can farsightedness be treated?
For adolescent patients with farsightedness, to use the ciliary paralysis muscle to eliminate the adjustment of optometry with glasses.Adult farsightedness, can be fitted with eyes, can also be treated by laser surgery, like myopia laser surgery.
