What do you need to know about the Schrimer Test?
The eye maintains a stable level of moisture and eliminates foreign particles by producing tears. When the eyes are too dry or too moist, the Schirmer test can be performed. The Schirmer test is also known as:
- dry eye test
- test for tears
- basal tear secretion test
The Schirmer test is mainly used to diagnose dry eye syndrome. This is a condition that occurs when the lacrimal glands are unable to produce enough tears to keep the eyes moist. As a result, the eyes cannot get rid of dust and other irritants. This causes stinging, burning and redness in the eyes. Blurred vision is another common symptom of dry eye syndrome. The likelihood of developing dry eye increases with ageing. The disorder is most common in people over the age of 50.
What does the Schrimer Test involve?
First you need to remove your contact lenses or glasses. Then you will be given anesthetic drops for eye numbing. These drops will stop you from tearing as a reaction to the test strips. The drops may cause irritation or stinging, but the sensation is temporary. Once the numbing sensation has set in, the doctor will gently pull your eyelid down and place a special paper strip under your eyelid. You will then keep your eyes closed for about five minutes with the strip of paper in place. During this time, it is important to avoid squinting or touching your eyes. This may alter the results. After the five minutes, the doctor will carefully remove the strips of paper from the bottom of each eyelid. Then the amount of moisture on each strip will be measured.
As an alternative to the Schirmer test, your doctor can also assess tear production with a red thread test. A red thread test is similar to the Schirmer test, but uses a thread instead of paper strips.
If the eyes are healthy, each paper strip should contain more than 10 millimeters of moisture. Less than 10 millimeters of moisture indicates that you probably 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 probably be needed to diagnose the specific cause of dry eyes. If the eyes produce more than 10 to 15 millimeters of moisture, further tests may be needed to determine the cause of the watery eyes.
What can be diagnosed with the Schrimer Test?
Abnormal Schrimer test results will prompt your doctor to look for the underlying cause of your condition.
Potential causes of dry eyes include:
- changes of season or climate
- eyelid or facial surgery
- laser eye surgery
- lupus or rheumatoid arthritis
- Sjögren’s syndrome
- taking certain medicines, such as antihistamines or decongestants
- vitamin A deficiency
Potential causes of excess tears include:
- climate, especially cold weather and wind
- blocked tear ducts
- complications due to dry eyes
- eye irritation
- ingrown eyelashes
- the common cold
- reactions to certain medicines, including diuretics and sleeping pills