Optometry 101: What is an Optometrist & What Eye Conditions Do They Treat

An optometrist is an eye doctor who has earned a Doctor of Optometry (OD) degree after attending college and graduating from a 4-year professional program. They perform eye tests and vision tests and detect diseases, injuries, and disorders related to the eyes. Optometrists treat eye conditions, such as nearsightedness, farsightedness, and astigmatism, and prescribe eyeglasses and contacts. They may also provide low-vision aids and vision therapy.

Each eye measures about 1” across and weighs about a quarter ounce; eyes remain about the same size throughout life. The eye is composed of about 2 million working parts and is the second most complex organ after the brain. What we see determines about 80 percent of our memories. Our eyes also protect us from danger.

There are various eye injuries and conditions that can interfere with our sight. Eye conditions include:

Refractive errors

Myopia (nearsightedness), hyperopia (farsightedness), and astigmatism (distorted vision). Eyeglasses, contact lenses, or in some cases surgery, can correct refractive errors.

Age-related macular degeneration (AMD)

AMD damages sharp vision used for seeing objects clearly and central vision used for reading, driving, and other daily tasks.


Characterized by the clouding of the eye’s lens, cataracts are the leading cause of vision loss in the United States.

Diabetic retinopathy

This complication of diabetes is the leading cause of blindness in adults in the U.S. It is the result of progressive damage to the retina, which is the light-sensitive tissue lining the back of the eye.


Glaucoma, which occurs when pressure increases inside the eye, is a group of diseases that can damage the optic nerve.

Optometrists provide sight-saving tips for optimal eye health. These tips include wearing sunglasses that block 99 percent of the sun’s UV rays, cleaning contacts thoroughly between uses, protecting eyes from injury, and undergoing a routine eye exam once a year.

Contact Illinois Eye Center at (309) 243-2400 to schedule your routine eye care appointment with one of our 7 Optometrists, and visit our website today for more information on general eye health and safety.

Memorial Day Holiday Hours

Saturday 5/25 – Peoria Office by Appointment Only
All Other Offices Closed

Monday 5/27 – All Offices Closed

Tuesday 5/28 – Resume Normal Hours at All Locations

Illinois Eye Center is open today, 01/23/2024, at all locations.

Check back here for updates before leaving home, as weather conditions may warrant future changes or closure.

If you prefer to reschedule, due to the weather please click the button below.

Holiday Hours

Saturday, 9/2

Peoria office open by appointment only

(Pekin & Washington are always closed on Saturdays)

Monday, 9/4

All offices closed

Tuesday, 9/5

Peoria & Pekin offices resume normal hours

Note: The Washington office will remain closed for renovations until Monday, Sept 18. 2023