Q: I’ve worn glasses since I was a child, but I can never remember what it means to be near or farsighted, let alone having astigmatism. Can you explain the basic terms and what they mean?
A: I must be asked this a million times a day! I think the confusion exists for a good reason: most medical problems are named for the problem. Vision problems are the opposite: they are named for the good aspect of your vision.
Here’s the big four in the world of vision:
- Nearsightedness: This means that you have better near vision than far vision. You likely can see up close just fine for reading, but things in the distance are blurry or out of focus.
- Farsightedness: This is the opposite of nearsightedness…..you can see better far away, but have problems focusing clearly for near objects or reading. These are often the people who brag about being able to see distance things sooner than anyone else….road signs, wildlife and virtually anything far away.
- Astigmatism: Likely this is the most misunderstood vision disorder. First, it is not a disease. It is simply a type of blurry vision like the first two examples….but it can can your vision to be out of focus at any distance! It can make reading uncomfortable or tiring, it can make road signs tough to read, it really affects vision everywhere. And to complicate matters, almost everyone has some degree of astigmatism. So for those individuals, their vision has two causes of blur!
- Presbyopia: This is likely the least explained vision problem, because few people want to hear about it! This is also the one vision disorder that no one, absolutely no one, escapes. Our eyes gradually lose the ability to focus up close as we age. Generally somewhere between age 35 and 50 everyone notices they must hold print further away from their face to read it. Patients often joke is that “my arms are getting shorter”. This is easily corrected, as are the others, with accurate glasses or contact lenses.
I should add that refractive surgery, like LASIK, is able to correct nearsightedness very well. It is not as precise in solving astigmatism, and generally not helpful in farsightedness or presbyopia. Likewise, we are often asked about “eye exercises” to improve vision……but this is completely without medical or scientific basis. Your vision is largely a result of genetics, and to varying extent how you use your eyes when growing up.
Lastly, nearsightedness is now able to be slowed down in progression for kids. Eye drops at bedtime, specialized contact lenses, or both, have been proven to improve the vision disorder that children would have by age 21 had they not had intervention treatments.
