Eye health resource
Eye Exam vs. Contact Lens Exam: What's the Difference?
A comprehensive eye exam checks vision and eye health; a contact lens exam evaluates the specific lens on your eyes. Learn why the fitting is separate, what each visit includes, and when you need both.
Reviewed for accuracy by Justin Bazan, OD on .
A comprehensive eye exam and a contact lens exam are related, but they are not the same service. The comprehensive exam determines how well you see and evaluates the health of your eyes. A contact lens evaluation determines which specific contact lens can safely and effectively correct your vision while sitting directly on your eyes.
That is why an eyeglass prescription alone is not enough to order contact lenses, and why a contact-lens fitting may have a separate fee and follow-up period.
What Does a Comprehensive Eye Exam Include?
A comprehensive eye exam looks at your overall vision and eye health. Depending on your age, symptoms, history, and findings, it can include:
- visual acuity;
- refraction to determine or refine an eyeglass prescription;
- eye alignment, focusing, and pupil responses;
- eye-pressure measurement;
- examination of the front of the eyes;
- evaluation of the retina and optic nerve; and
- retinal imaging, OCT, dilation, or other testing when appropriate.
The goal is broader than simply deciding what power of glasses you need. A person can see 20/20 and still have an eye-health issue that deserves attention.
What Does a Contact Lens Exam or Fitting Add?
Contact lenses are medical devices that sit on the eye. Two lenses with the same written power can differ in material, shape, diameter, thickness, optical design, and how they move on the eye.
A contact-lens evaluation can therefore include:
- reviewing how you plan to use contact lenses;
- evaluating the cornea, eyelids, tear film, and ocular surface;
- selecting an appropriate lens type, material, and design;
- placing a trial lens on the eye when appropriate;
- checking how the lens centers, moves, and rotates;
- measuring vision through the actual lens;
- adjusting power or design when needed;
- reviewing safe insertion, removal, wear, replacement, and hygiene; and
- following up when necessary before the fitting is considered complete.
Why Isn't My Glasses Prescription My Contact Lens Prescription?
Glasses sit in front of the eyes. Contact lenses sit directly on the cornea. That change in position can affect the required lens power, especially with stronger prescriptions.
A contact lens prescription also identifies the actual lens being prescribed. Depending on the lens, that can include the manufacturer or brand, power, base curve, diameter, astigmatism parameters, multifocal design, or other specifications.
The prescription is therefore not just a converted eyeglass number. The lens has to fit and perform appropriately on your eyes.
Do I Need Both Visits?
If you want a comprehensive assessment of your vision and eye health and you want contact lenses, then yes—the two parts of care need to be covered.
They may occur on the same day or as part of the same overall episode of care, but the contact-lens fitting remains a separate professional service because it involves additional evaluation and lens-specific decision-making.
What If I Already Had a Recent Eye Exam Somewhere Else?
You do not necessarily have to repeat a recent comprehensive exam just to have contact lenses fit at Park Slope Eye.
If you had a comprehensive eye examination elsewhere within about three months, we can generally use that exam as long as we receive a copy of the complete comprehensive-exam record. An eyeglass prescription by itself is not enough.
If we do not have documentation of the recent comprehensive exam, or if there is a new eye-health concern, we will need to perform a comprehensive eye exam before proceeding with the contact-lens fitting.
What If I Already Wear Contacts and Just Need a Renewal?
An established wearer may not need the same process as someone being fit for contact lenses for the first time, but the doctor still needs enough information to determine that the prescription remains appropriate.
We look at how your current lenses are performing, whether your vision or prescription has changed, and whether the lenses continue to fit and interact safely with the eyes.
Why Can a Contact-Lens Fitting Need Follow-Up?
A trial lens may look promising during the first few minutes and behave differently after real-world wear. Follow-up allows us to assess comfort, vision, wearing time, lens movement, ocular-surface response, and any problems that appeared after you left the office.
Park Slope Eye's self-pay contact-lens fitting and follow-up period is generally about 90 days. Current fees are kept on our Insurance, Fees & Patient FAQs page so this article does not become outdated when pricing changes.
What Types of Contact Lenses Does Park Slope Eye Fit?
Our current lens categories include:
- standard soft contact lenses;
- toric lenses for astigmatism;
- multifocal and monovision options for distance and near vision;
- scleral lenses;
- corneal GP/RGP lenses;
- Ortho-K lenses worn overnight; and
- appropriate soft myopia-control contact lenses for children.
If conventional lenses have not worked well for you, see When Regular Contact Lenses Don't Work.
When Do I Get My Contact Lens Prescription?
Your contact lens prescription is provided when the fitting is complete. You are not required to purchase your contact lenses from Park Slope Eye in order to receive the prescription.
We do appreciate the opportunity to quote your lenses because our pricing is often very competitive and contact-lens sales support the independent practice—but the choice of where to purchase is yours.
Which Appointment Should I Book?
If you need a full eye-health and vision examination, start with a comprehensive eye exam. If you have a recent qualifying comprehensive exam and need contact lenses, or you are having a problem with your current contacts, see contact-lens exams and fittings. Those service pages contain the current online-booking options.