In order to get a prescription for contact lenses, you must have a complete contact lens fitting.

A prescription for contact lenses is not the same as a prescription for eyeglasses. To obtain a contact lenses prescription, the doctor will first do a refraction to determine your refractive error, and then take additional measurements, which include the corneal curvature. These anatomical measurements are equivalent to the “shoe size” for your eyes. Since humans come in different shapes and sizes, it stands to reason the eyes come in a varying array of curvatures. Since the contact lens rests at the corneal plane, the prescription must then be converted from the spectacle plane to compensate for the vertex distance (distance between the cornea and the back surface of your spectacles). The health of the cornea and tear layer must also be evaluated to determine the proper moisture content and material best suited to your individual needs. As you see, a prescription and fitting for contact lenses is more involved than an exam for spectacle lenses. The fitting fee for a contact lens exam costs more because it requires more office time and also includes the follow up care that will ensure optimal fit and performance with your new lenses. A final prescription for contact lenses will be determined after the follow up care indicates patient and doctor satisfaction with the comfort level and performance of the chosen mode of wear. A contact lens prescription expires after 12 months. By law, contact lens fitting and eye health evaluation has to be done every time you get an eye exam if you want to get your contact lens prescription renewed. This is a patient safety issue to prevent chronic over wearers from causing themselves permanent damage. These scenarios can usually be prevented with regular evaluation by a qualified eye care professional.