A comprehensive eye exam is one of the first steps toward good eye care. In addition to evaluating whether you need contacts or glasses, an eye exam can be a lifesaver in helping to detect eye diseases such as glaucoma, macular degeneration, or cataracts in the early stages. At your appointment, you can expect to undergo several types of eye tests. Each test evaluates a different aspect of your eye health and vision. Here’s a brief guide to the tests your optometrist may perform during an eye exam.
Visual Acuity Test
The image of an eye chart mounted on the wall of an optometrist’s office is probably the first thing that comes to mind when you think of an eye exam. The “eye chart” test is known as a visual acuity test. Using one eye at a time, your optometrist asks you to read a series of letters printed on a Snellen chart. As you move down the chart, the letters will get smaller. Your optometrist uses your responses to get a general idea of how well you see over near and far distances.
Visual Field Test
We normally get a wide view of the area in front of us. Without moving our eyes, we can see what is above, below, and off to either side. The entire area is known as the visual field. A visual field test measures how far your eyes can see while focused on a single point. Your eye doctor will check for the presence of blind spots in your peripheral vision. The blind spots can originate from various conditions, including glaucoma and stroke.
There are several types of visual field tests:
- Automated perimetry: As you look into a large bowl-like machine with blinking lights, you press a button any time you see a light flash in your peripheral vision.
- Confrontation exam: Your optometrist sits directly in front of you and moves their hand in and out of your peripheral vision. You look straight ahead and say when you see the hand move into and out of view.
These tests allow your eye doctor to determine the size of your visual field and identify gaps in your peripheral vision.
Silt Lamp Exam
During a silt lamp exam, your eye doctor will use a binocular microscope to examine the structures of your eye under high magnification. They will begin by examining the eyelids, lashes, iris, cornea, lens, conjunctiva, and the fluid chamber between your cornea and iris. Your optometrist may also examine internal structures of the eye, such as the optic nerve and retina. The silt lamp exam can detect a wide range of eye conditions and diseases, including cataracts, corneal ulcers, macular degeneration, detached retina, diabetic retinopathy, and dry eye disease.
The Glaucoma Test
This test measures the pressure inside your eyes to help diagnose glaucoma. A common glaucoma test is called non-contact tonometry (NCT), also known as the “puff-of-air” test. The doctor will use a device called a tonometer that blows a small puff of air at your open eyes, measuring eye pressure based on the eye’s resistance to the puff. If you have high eye pressure, you may have or may be at risk for glaucoma.
Eye pressure can also be measured using an applanation tonometer. This is the most accurate method, but you’ll need numbing eye drops combined with yellow eye drops that glow under blue light. The doctor will gently touch the surface of your eye with the tonometer to measure your intraocular pressure (IOP).
The optometrist uses special drops to temporarily dilate your pupils (make them larger). That gives your doctor a better view of the eye’s internal structures and allows them to check for signs of disease.
Color Blindness Test
Often performed early in a comprehensive eye exam, the color blindness test checks your color vision to rule out color blindness. It can also alert your optometrist to possible eye health problems that cause color blindness in the future.
This is the eye test used to determine your eyeglasses prescription. The exam requires you to look at a chart, usually 20 feet away, through a device called a phoropter. This test is performed in a dark room for a better view of images. Your optometrist displays lenses of different strengths for you. You can tell them if images look clear or blurry. They’ll use your responses to determine which corrective lens prescription will give you the sharpest, clearest vision.
This is an alternative to the visual refraction test. Instead of using your responses to approximate your optimal lens prescription, your optometrist uses a phoropter to shine a light into your eyes and have you look at a large target. They will flip lenses in front of your eyes and watch how the light affects your eyes with different lenses. This exam is especially useful for children and patients who cannot communicate or provide accurate responses.
Schedule An Eye Exam with Atlantic Eye Consultants, P.C. Today
Dr. Delianides and his team at Atlantic Eye Consultants are committed to providing high-quality eye care in a comfortable environment. We use state-of-the-art technology to correct and enhance your eyesight, resulting in improved vision and better quality of life. Whether you’re experiencing vision issues or haven’t had an eye exam for a while, reach out to our practice to schedule an appointment.