You may notice a difference in your contact lens prescription if you wear contacts lenses or if you are considering switching from eyeglasses to contacts. Contact lens prescriptions include extra abbreviations and numerical information that are not included on glasses prescriptions. They also contain specific information about the lenses’ fit.
The main difference between a contact lenses prescription and a glasses one is that the contact lens script will include abbreviations as well as numbers for each eye. You’ll usually see the abbreviations OD (oculus dexter) and OS (oculus sinister) next to each eye, with a number in front of them that indicates the strength of the vision correction for that eye. The number is either a plus (plus) or minus (-), based on whether you are nearsighted or farsighted.
Your contact lens prescription will also often include the abbreviation “CYL”. This is short for cylinder, and it refers to the amount of astigmatism you have. If you suffer from astigmatism, the prescription for your contact lenses will include a cylinder-correction in addition to any spherical correction needed for normal vision.
You might also see the abbreviation OU on your contact lens prescription, which stands for “unilateral.” This means that you have a condition called monocular astigmatism, which is where you have astigmatism in both eyes but not as strongly in one eye as in the other. Your doctor may recommend that if you suffer from monocular astigmatism you wear contact lenses corrected with a CYL. This makes it easier to read your prescription and manage.
The base curve may also be included in the contact lens prescription, which is something that glasses prescriptions do not include. This value is important for contact lenses, because it refers to how the curve of your cornea matches the shape of the contact lens you’re wearing. This is important for ensuring the lens fits your eye properly and will determine how comfortable and clear it will be.
These tools are not always accurate. While some websites claim that they can convert your glasses prescription into contact lens prescriptions, this is not always the case. In many cases, the results will be inaccurate because of the extra specifications that are included in a contact lens prescription. To get an accurate and complete translation, you must visit your eyecare provider for a contact lenses exam and fitting.
Please don’t hesitate if you have any questions regarding the reading of your contact lens prescription. Our friendly team of experts will be happy to help. You can reach our team at 888-576 3937. We look forward hearing from you.