by Ariel Seafish
Q: Hi everyone,
Two years ago I had my eyes checked and these was the prescription with cylindrical lenses:
OD: (SPH /) (CYL+0.25) (Ax 70)
OS: (SPH +0.5) (CYL+0.5) (Ax 100)
I was not sure if the glasses were only for reading, for distance or for both. Moreover, for some reason the right eye gave me such a pain that I quit wearing them in less than 2 weeks.
Yesterday I visited an eye doctor again and got this prescription:
OD: (SPH +0.75) (CYL 0.5) (Ax 150)
OS: (SPH +1.00) (CYL /) (Ax /)
The doctor said that I should wear them all the time. He said that I have problems reading because I actually have problems with distance vision. Fair enough, I do have some problems reading the street signs especially during the night.
What is unclear to me are the following:
1. Can a person have eyeglasses with "+" for distance?
2. Can someone goes from cylinder (OS: +0.5) to no cylinder (OS) and from Ax 70 (OD) to Ax 150 (OD)?
3. Can the spheres grow in 2 years from none to 0.75?
4. Wearing eyeglasses if you actually do not need them can impair your vision for good?
A: Hello Ariel
What I can tell you from the beginning is that the two prescriptions you have with cylindrical lenses are written in two different ways.
The first is with (+) cylinder and the second with (-) cylinder this is why they look different. If we put them both with (+) cylinder, then the second will look like this:
OD: (sph +0.25) ( cyl +0.50) (ax 60)
So the difference between the first and the second prescription is small.
Now to answer your questions:
1. Yes, you can have (+) for distance view and is called Hyperopia, commonly known as being farsighted.
2. No, presence of cylinder means you have astigmatism, an eye condition that does not disappear, but normally, if the cylinder is not more than 1 diopter (0.25; 0.50), the correction is not mandatory, you will get a correction for it only if improves your vision. I see that first time you had it, but as you said you had a pain in the right eye wearing this glasses, the doctor was thinking that maybe this cylinder is to blame so next time he didn't put it there.
3. Yes, it can grow that much. It depends on how tired you'r eyes are, how much you are reading or working on computers on daily bases and if you wear a hyperopia correction or not. All this factors together can damage your vision over time.
4. If the diopters in these eyeglasses are big and you don't need them, they can do damage. Usually, you feel dizzy, have blurred vision or headaches, so you are not able to wear them anyways. If the diopters are rather small, like in your case, wearing them only get you more tired eyes, no permanent damage.