What is the Difference between your Glasses Prescription and your Contact Lens Prescription?

This is a very common question and can sometimes be confusing so we would like to clarify the differences and our clinic policies.

A “routine eye examination” provides an overall eye health evaluation for diagnosis of eye diseases such as glaucoma, cataracts, macular degeneration, etc. It will also determine a patient’s “refractive error” or combination of lenses to maximize your vision. Those numbers are your glasses rx. In many cases your medical insurance will cover this examination under your preventative care benefit.  Vision plans such as VSP and EyeMed will usually cover this service also. Please check with your insurance carrier to determine your coverage. A glasses rx is valid for 2 years. If a patient feels their glasses rx has changed and would like the prescription recalculated, we offer that service at no charge for the first six months of the two year rx. After that, fees may apply.

To determine the contact lens prescription, the doctor uses the glasses rx as a starting point but also has to take into account the curvature, diameter and health of the cornea, the distance from the cornea to the spectacle plane, the availability of various powers and the best lens material for the patient. Other considerations also include the type of lens which can include soft, rigid gas permeable, toric for astigmatism, multifocal, monovision, scleral lenses, disposable, etc.  These and other variables can often make determining the contact lens prescription a difficult and time consuming process sometimes requiring several visits.

Contact lenses are defined by the FDA as medical devices and rules for providers apply. First time contact lens wearers must successfully complete the “insertion and removal” class in which our staff will take as much time as needed to teach the patient how to insert and remove the contact lenses. Contact lens safety, care of the contacts and solutions will also be discussed. Doctors must then assess the contact lenses positioning on the eye, corneal health, patient compliance, and vision on a regular basis which can vary greatly from one patient to the next.

Once the patient is satisfied with the vision and comfort of the contact lenses and the doctor is satisfied that the patient is being compliant and eye health will not be compromised, the contact lens prescription can be finalized.  This prescription can be legally filled at the discretion of the patient for a maximum of two years. At that time the doctor will need to reassess corneal health and contact lens parameters. Our policy is to change the contact lens prescription at no charge for the first six months of the two year prescription period if the patient feels their vision has changed. After that, fees may apply for changes made to the prescription.

Most insurance companies consider contact lenses to be cosmetic and will not pay for contact lens services (fitting) fees charged by the doctor.  These service fees can vary greatly in the type of contact lenses needed are usually the patient’s responsibility. Please let us know if you have any questions.

Thanks! Dr. Steve