Visual Field Testing

During a routine eye exam, some eye doctors may want to determine through visual field testing the full horizontal and vertical range of what you are able to see peripherally. This range is commonly referred to as "side vision."

Visual field tests assess the potential presence of blind spots (scotomas), which could indicate eye diseases. A blind spot in the field of vision can be linked to a variety of specific eye diseases, depending on the size and shape of the scotoma.

Many eye and brain disorders can cause peripheral vision loss and visual field abnormalities.

For example, optic nerve damage caused by glaucoma creates a very specific visual field defect. Other eye problems associated with blind spots and other visual field defects include optic nerve damage (optic neuropathy) from disease or damage to the light-sensitive inner lining of the eye (retina).

Brain abnormalities such as those caused by strokes or tumors can affect the visual field. In fact, the location of the stroke or tumor in the brain can frequently be determined by the size, shape and site of the visual field defect.

Types of Visual Field Tests

Confrontation visual field testing typically is used as a screening visual field test. One eye is covered, while the other eye fixates on a target object, such as the doctor's open eye, while the doctor stands or sits directly in front of you. You then are asked to describe what you see on the far edges or periphery of your field of view.

If an eye disease is suspected, you may need to undergo more comprehensive, formal types of visual field testing to evaluate the quality of your central and peripheral vision.


The picture to the right shows a patient who doing visual field testing with a Humphrey Field Analyzer (HFA), which uses automated perimetry to measure responses to visual stimuli appearing in central and side vision. (image by Zeiss)     By Marilyn Haddrill; contributions and review by Charles Slonim, MD

Glaucoma 101

Glaucoma is one of the "silent blindness" disease of older folks all over the world. Most glaucoma has no symptoms at all, no warning that there is a problem. The only way to know that you have glaucoma is to have a complete eye examination performed by an eye doctor. Even then addtional testing might be necessary.

Glaucoma is damage to the optic nerve, the nerve that carries "light" from the eye to the brain. It usually comes with high eye pressure, but not always. There are lots of people who have glaucoma who have eye pressure that seems normal, and there are even more people who have high pressure who will never get glaucoma. The "normal" pressure in the eye is 11-21. Most people who get glaucoma are older, usually older than 60.

There are several ways to measure pressure in the eye. The two most common methods are Non-Contact Tonometry--the air puff-- and Contact Tonometry--the blue light. The "blue light" technique is much more accurate and is necessary to treat glaucoma. The "air puff" is a great screening test for glaucoma because it's easy to do, and easy to have done.

There's lots to talk about with Glaucoma so we'll try to teach you as much as we can here on the Skyvision Blog. All of our Doctors, Dr. White, Dr. Kaye, and Dr. Schlegel have lots of experience in treating people with glaucoma here in Cleveland. Stay tuned!