Myopia, farsightedness, astigmatism, presbyopia, and amblyopia are all common vision problems, but their causes and methods vary.
Myopia is when you can see near objects clearly when reading a book or looking at a computer at close range, but you can't see clearly at a distance. This is usually caused by the eyeball being too long or the curvature of the cornea. People with myopia need to wear concave lenses to correct their vision, and adults can also correct their vision through myopia surgery to achieve the purpose of not wearing glasses, but they need to be measured in combination with their own glasses.
Farsightedness refers to not being able to see clearly at both distance and near distance, but seeing clearly at intermediate distances. This is usually caused by a short eyeball or a corneal curvature that is too flat. People who are farsighted need to wear convex lenses to correct their vision.
Astigmatism is the inability to see objects clearly even at close or long distances. This is usually due to the difference in the curvature of the cornea in the horizontal and vertical directions. People with astigmatism need to wear cylindrical lenses to correct their vision.
Presbyopia is a visual problem that develops after middle age, manifested by difficulty in seeing at close range, requiring increased lighting or progressive multifocal glasses to help adjust the focal length. This is due to the gradual hardening of the lens inside the eye.
Amblyopia refers to the poor development of vision due to various reasons in childhood, such as congenital cataracts, corneal degeneration, etc. People with amblyopia need to receive special ** to stimulate vision development, including masking**, visual training, etc.
In short, although myopia, farsightedness, astigmatism, presbyopia and amblyopia are all visual problems, their pathogenesis and methods are different. Therefore, if you have vision problems, it is best to go to the hospital in time to receive a professional examination and**.