What is the Schirmer’s Test?
The human eye maintains a stable level of moisture and eliminates foreign particles by producing tears. When your eyes are too dry or too wet, you may be given Schirmer’s test. This test will show whether your eyes produce too few or too many tears to maintain optimal eye health. Schirmer’s test is primarily used to diagnose dry eye conditions.
Schirmer’s test is also known as a dry eye test, tear test, tearing test, or Basal secretion test.
Prevalence of Dry Eye Syndrome
According to a 2003 study published in the American Journal of Ophthalmology, women are more likely than men to suffer from dry eye syndrome and the likelihood of dry eyes increases with age. The study found that an estimated 3.2 million American women middle-aged and older suffer from some form of dry eye syndrome. (Schaumberg, et al., 2009)
A 2009 study published in the Archives of Ophthalmology found that the likelihood of dry eye syndrome in men also increases with age. Roughly 1.68 million American men over the age of 50 suffer from a dry eye disorder. In addition, the study found that high blood pressure and the use of antidepressants and anti-hypertensives are associated with a greater risk of dry eye conditions. (Schaumerg, et al., 2000)
Causes of Too Few/Too Many Tears
Potential causes of dry eyes include:
- a bacterial infection
- climate change (or seasonal changes)
- eyelid or facial surgery
- laser eye surgery
- rheumatoid arthritis
- Sjogren syndrome (an autoimmune disorder)
- vitamin A deficiency
Potential causes of excess tears include:
- a strong emotional response (crying)
- climate (including cold and/or windy weather)
- blocked tear ducts
- complications from dry eyes
- irritation of the eye (from stray eyelashes or other debris)
- ingrown eyelashes
- relaxation of eye muscles (limits the eye’s ability to drain)
- the common cold
- pink eye (conjunctivitis)
- reactions to certain medications (antihistamines, eye drops, diuretics, sleeping pills, etc.)
Schirmer’s Test Procedure
Your optometrist will recommend Schirmer’s test if you are exhibiting signs of dry eyes, or in some cases, watery eyes.
If you wear corrective contact lenses, you will need to remove them before the test. It is best to bring your glasses because you should keep your contact lenses out for at least two hours after the test.
Before the test is administered, your optometrist will put numbing drops into your eyes. These 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.
Next, the optometrist will ask you to look upward. He or she will pull out your bottom eyelid and gently place a special strip of paper underneath the lid. Both eyes may be tested at the same time. You will gently close your eyes and keep them shut for about five minutes with the paper strip in place. Closing your eyes too tightly or touching your eyes during the five-minute test process could alter the results.
After five-minutes, the ophthalmologist will take out the paper strips. The doctor will ask you to look upward as he or she pulls out your bottom eyelid and carefully removes the strips. The doctor will then measure the amount of moisture on each paper strip.
There are no known risks associated with Schirmer’s test.
As an alternative to Schirmer’s test, your doctor can also test tear production with Fluorescein eye drops or a red thread test. A red thread test is similar to Schirmer’s test, but uses thread instead of paper. Another option is a tear osmolarity test which measures how concentrated your tears are. A higher concentration signals dry eyes. Talk to your about your testing options.
What Do the Test Results Mean?
If your eyes are healthy, each test paper should contain more than 10 millimeters of moisture. Less than 10 millimeters of moisture indicates that your eyes are dry. The diagnosis of dry eyes could mean that you have other health issues, such as rheumatoid arthritis or a bacterial infection. More tests will likely be required to diagnose the specific cause of your dry eyes. If your eyes produce far more than 10 to 15mm of moisture, further tests may also be required to determine the cause of your watery eyes.