Optometrists: What Eye Exams Do They Use and Why

An optometrist is a certified healthcare professional who specializes in the examination of the eyes for overall health and screening for defects in vision or eye abnormalities that can affect the health of the eye.

A routine eye check-up completed by an optometrist is the recommended way to make sure your eyes are healthy, you do not have any underlying eye disease that is going unrecognized, and your glasses or contact lens prescription is up to date.

If you have ever wondered what eye exams your optometrist uses at your appointments and what they are measuring, these are a few of the most common tests that are used to check your vision and overall eye health during a schedule eye check up.

Visual Acuity Measurement

Visual acuity measurement is one of the most important components of a routine eye check up. The tests involved in measuring visual acuity give your optometrist a better idea of how sharp your vision is and if you are nearsighted or farsighted and by how much.

This helps them to get a better understanding of how your glasses or contacts prescription is changing. Some eye diseases, such as cataracts, may also impact visual acuity, and visual acuity testing is a component of screening for these diseases as well.

Visual acuity testing commonly involves reading increasingly smaller letters or numbers from a screen known as a Snellen chart. It may also involve looking through a set of glasses or lenses at a small image and telling your optometrist if these images are getting sharper or blurrier.

Intraocular Pressure Measurement

For many people, the “puff of air test” is among the more memorable parts of an eye exam. During this component of the exam, your forehead is placed against a machine that blows a small puff of air into each eye.

The purpose of this test is to measure the pressure inside the eye. For some eye conditions, such as glaucoma, the pressure inside the eye may be increased, and medications may be required to reduce it.

Color Vision Assessment

A routine eye check up also commonly includes an assessment of color vision. This is especially important for adults who are of age to drive since they need to be able to differentiate between the colors of traffic lights while behind the wheel.

In a color vision assessment, you will be asked to look at several circles that contain dots of different colors. In all of the circles, you should be able to see a number, e.g. 12. If you are unable to see a number that is a different color from the rest of the circle, it is a sign that you may have problems with your color vision.