If you’re thinking about switching from glasses to contact lenses, you might assume that your regular eye exam is all you need. But this isn’t the case. Our team at River City Vision Center can help you understand why a separate exam is required to get a prescription for contact lenses.
A contact lens exam includes a comprehensive eye health check plus several other tests and measurements that help ensure your contacts fit properly and give you clear vision. These extra steps are key to comfort and keeping your eyes healthy while you wear your lenses.
Regular Eye Exams vs. Contact Lens Exams
Think of your standard eye exam as the foundation of your ocular health. A contact lens exam builds on that foundation with an additional fitting process.
Because contact lenses sit directly on your eyes, your optometrist will need to perform additional measurements to make sure that they fit correctly. This helps ensure that your lenses match the shape of your eyes, feel comfortable, and provide the vision correction that you need.
What to Expect During Your Contact Lens Exam
The main purpose of a contact lens exam is to find the right lenses for your vision needs and lifestyle.
Special Measurements for Your Lenses
Glasses sit a short distance from your face, but contacts rest right on your eyes. The closer fit of contact lenses means that their sizing has to be just right.
In order to get the fit right, your optometrist will measure different properties of your eyes. These include:
- The curve of your cornea (the clear front surface of your eye)
- The size of your iris and pupil
A Trial Lens Fit & Follow-Up
You’ll likely try on a pair of trial lenses during your appointment. Your optometrist will then check how the lens sits on your eye, how much it moves when you blink, and how well you can see. Your comfort is their top priority.
A follow-up visit is often scheduled a week or two later. This allows your optometrist to see how your eyes are adjusting to your new lenses.
Why Your Glasses Prescription & Contact Lens Prescription Are Different
Prescriptions for glasses and prescriptions for glasses aren’t interchangeable. Because glasses and contacts sit at different distances from your eye, the optical power that their lenses need to correct your vision isn’t actually the same. The stronger your prescription, the bigger this difference is.
Your contact lens prescription also contains specific details that you don’t need to get glasses. These details include:
- Base Curve (BC): This number indicates what the curvature of your contact lens should be, so that it can match your cornea.
- Diameter (DIA): This is the distance across the lens, so that it’s wide enough to cover your eye.
Specific Lens Brand & Material
Your prescription will also name a brand and type of contact lens. Different brands are made from different materials, which affects moisture retention and how much oxygen can pass through to your eye.
Who Is a Good Candidate for Contact Lenses
Most people who need vision correction can wear contact lenses without any problem. In some cases, certain health conditions may require specialty contact lenses. If you experience any of the following, your doctor will discuss your choices and may recommend different types of lenses:
- Frequent dry eyes
- Severe allergies
- A history of recurring eye infections
The Importance of a Professional Fit
A proper contact lens fit from a qualified optometrist helps protect your eye health. Regular yearly eye exams are also important to monitor the health of your eyes and keep your prescription up to date. Our team at River City Vision Center is here to help you with all of your eye care needs. If you’re interested in contact lenses or need to update your prescription, contact our office to schedule your exam with an optometrist today.
