What your eye doctor looks for at a contact lens fitting

Determining your prescription

During this part of the exam, your eye doctor will use a device called a phoropter to find out how much correction each of your eyes need. You’ll be asked: “Which is better? Number one or number two,” because they’re cycling through different lens powers and seeing which ones provide you with the sharpest vision. For some, this test can be frustrating since it’s subjective and sometimes can be hard to tell which option is, in fact, better. But it tends to be the best way to get your prescription as accurate as possible. Rest assured, the person asking you “Which is better?” is trained to revisit any of your answers that seem unsure or ambiguous. Your eye doctor may also opt to use other tools like a retinoscope. A retinoscope shines a light into your eye, and depending how the light reflects off the retina, the doctor can determine your prescription.

Ensuring your eyes working as a team

Another part of the exam will test for abnormalities in the way your eyes function and/or move together. Your eye doctor may test this by moving an object around in different directions and asking you to follow with your eyes.

Inspecting the outside of your eyes

In this part of the exam, your eye doctor will take a look at the external parts of your eyes like your eyelashes, your cornea (the front surface of your eyes) and your iris (the colored part of your eye) with a special microscope called a slit lamp.

Checking inside your eye

Your doctor may want to dilate your pupils, especially if this is your first visit with them. This procedure allows them to better see through to the back of the eye and evaluate the health of your retina and optic nerve inside the eye. This is especially important if you are nearsighted as nearsighted people have a higher risk of developing retinal problems.

Once your eye doctor confirms that your eyes are healthy enough for contact lenses and the measurements are taken, they will then select a trial lens and put it on your eye. Once the lens is on the eye, they will determine if it’s a good fit by:

• Checking how well the lens centers over your cornea
• Observing how much the lens moves when you blink
• Making sure the lens feels comfortable and provides clear vision
• Adjusting the fit by changing parameters like base curve or diameter if needed

Once your eye doctor chooses lenses that fit your eyes well, they’ll give you instructions on how to place, remove, clean, and care for your lenses. You’ll go home with trial lenses to wear for a few days to a week or so to make sure they’re comfortable and correct your vision well. After the trial period, you’ll go back to the doctor’s office to make sure the lenses are working properly, and if so, you’ll go home with your prescription. During the follow-up appointment, it’s important to share any and all issues that you experienced so that they can make adjustments if needed.