Is your eye glasses prescription the same as contacts?!

Is your eye glasses prescription the same as contacts?

i got my eye exam and its _4.50 now eye doctor tells me i have to get another one to fit my diamitor but two years ago i got contacts and and have my boxes and the info on them can i order new contacts at my eye glasses perscription or are they diffrent cuz their actually on your eye instaid of your glasses cuz ther a lil farther away?

Your contact prescription is totally different than your eyeglass prescription in at least one and many times two ways. Your eye glass prescription only provides information as to the POWER of the prescription. The contact lens prescription will give the dispenser of your contacts FITTING information. This information consists of 1) the base curve of the contact lens (the cuvature of the lens is critical as to how well the contact lens will fit the curvature of your eye) 2) diameter of the lens (this is probably less critical to the fit though) 3) brand of contact lens (just like different brands of shoes tend to fit differently -- likewise different brands of contact lenses may fit differently even though they have the same base curve and diameter)

One other thing that may be different (and in your case it will be) is the actual power of the contact lens. When the doctor examines your eyes for eyeglasses his testing is done approximately 12mm IN FRONT of your eyes. Since the contact lens will actually be in contact (hence the name contact lenses) it will be necessary to make an adjustment in the power due to what is called vertex distance. When the power goes above -4.00 it is necessary to make a change in the CL power to account for the vertex distance. As the power of your glasses prescription increases the amount of adjustment the doctor will make to your contact prescription will increase. Since you are a -4.50 the doctor will need to calculate an adjustment for your vertex distance.

The reasoning behind the need for a different examination for your contacts goes deeper than this, though. Because contacts come in contact with your eyes there is risk that they can cause disease and damage to your eyes. The doctor therefore will need to perform different tests to assess the appropriateness of the fit of the contact and also verify that your eyes have remained healthy from your previous lens wear and you are therefore still a good candidate to continue to safely wear contact lenses. Hope this helped.