What Is the Schirmer’s Test?
The eye maintains a stable level of moisture and eliminates foreign particles by producing tears. When your eyes are too dry or too wet, your doctor may perform the Schirmer’s test.
The Schirmer’s test is also known as the:
- dry eye test
- tear test
- tearing test
- Basal secretion test
The Schirmer’s test is primarily used to diagnose dry eye syndrome. This is a condition that occurs when the tear glands are unable to produce enough tears to keep the eyes moist. As a result, the eyes can’t get rid of dust and other irritants. This causes stinging, burning, and redness in the eye. Blurred vision is another common symptom of dry eye syndrome.
The likelihood of developing dry eye increases with age. The condition is most common in people age 50 and older. It’s estimated that there are 5 million Americans in this age group with the condition. The majority of them are women, but dry eye does occur in many men as well.
Your doctor will order a Schirmer’s test if they suspect that your eyes are producing either too many or too few tears. The test may be done on one eye or both eyes, but it’s typically done in both. Abnormal test results will prompt your doctor to look for the underlying cause of your condition.
Potential causes of dry eyes include:
- changes in season or climate
- eyelid or facial surgery
- laser eye surgery
- lupus or rheumatoid arthritis
- Sjogren’s syndrome
- taking certain drugs, such as antihistamines or decongestants
- vitamin A deficiency
Potential causes of excess tears include:
- climate, particularly cold and windy weather
- blocked tear ducts
- complications from dry eyes
- irritation of the eye
- ingrown eyelashes
- the common cold
- pink eye
- reactions to certain medications, including diuretics and sleeping pills
There’s no special preparation required for the Schirmer’s test. However, if you wear contacts, you should bring your glasses with you to your appointment. You’ll need to keep your contact lenses out for at least two hours after the test.
Your doctor will first ask you to remove your contact lenses or glasses. They will probably then place numbing drops into your eyes. These drops will prevent your eyes from watering in reaction to the test strips. The numbing drops may cause irritation or stinging, but the sensation is temporary.
Once the numbing sensation has taken effect, your doctor will gently pull on your bottom eyelid and place a special strip of paper underneath the lid. Both eyes may be tested at the same time. Your doctor will instruct you to close your eyes and to keep them shut for about five minutes with the strip of paper in place. During this period, it’s important to avoid squeezing or touching your eyes. Doing so may alter the results.
After five minutes, your doctor will carefully remove the strips of paper from the bottom of each eyelid. They’ll then measure the amount of moisture on each strip.
As an alternative to the Schirmer’s test, your doctor may also assess tear production with a red thread test. A red thread test is similar to the Schirmer’s test, but it uses thread instead of paper strips. Talk to your doctor about your testing options.
If your eyes are healthy, each strip of paper should contain more than 10 millimeters of moisture. Less than 10 millimeters of moisture indicates you probable have dry eye syndrome. Dry eye could just be a symptom of aging, or it could be a symptom of an underlying health condition, such as rheumatoid arthritis. More tests will likely be required to diagnose the specific cause of your dry eyes.
If your eyes produce more than 10 to 15 millimeters of moisture, further tests may also be required to determine the cause of your watery eyes.