Your eyes are irritated, red, scratchy, and even watery. You made an appointment with an eye doctor. How do you know what tests should be performed to diagnose chronic dry eyes?
What is chronic dry eye syndrome?
Dry eye is a condition in which a person doesn’t have enough quality tears to lubricate and nourish the eye. Tears are necessary for maintaining the health of the eye’s front surface and for providing clear vision.
Dry eye is a common and often chronic problem, particularly in older adults. With each blink of the eyelids, tears spread across the front surface of the eye, known as the cornea. Tears provide lubrication, reduce the risk of eye infection, wash away foreign matter in the eye and keep the eyes’ surface smooth and clear. Excess tears in the eyes flow into small drainage ducts in the eyelids’ inner corners, which drain into the back of the nose. Dry eyes can occur when tear production and drainage are not in balance.
- Decreased amount of tears. Tears are produced by several glands in and around the eyelids. Tear production tends to decrease with age, with various medical conditions, or as a side effect of certain medicines. Environmental conditions, such as wind and dry climates, can also decrease tear volume due to increased tear evaporation. When the usual amount of tear production decreases or tears evaporate too quickly from the eyes, dry eye symptoms occur.
- Low quality of tears. Tears are made up of three layers: oil, water, and mucus. Each component protects and nourishes the front surface of the eye. A smooth oil layer helps prevent evaporation. The mucin layer spreads the tears evenly over the surface of the eye. If the tears evaporate too quickly or do not spread evenly over the surface of the eye, dry eye symptoms develop.
Risk factors for chronic dry eyes
- Age. Dry eyes are a part of the natural aging process. The majority of people over age 65 experience some symptoms of dry eyes.
- Gender. Women are more likely to develop dry eyes due to hormonal changes caused by pregnancy, the use of oral contraceptives, and menopause.
- Medications. Certain medicines, including antihistamines, decongestants, blood pressure medications, and antidepressants, can reduce tear production.
- Medical conditions. People with rheumatoid arthritis, diabetes, and thyroid problems are more likely to have dry eye symptoms. Also, problems with inflammation of the eyelids (blepharitis), inflammation of the eye surfaces, or the inward or outward turning of eyelids can cause dry eyes to develop.
- Environmental conditions. Exposure to smoke, wind, and dry climates can increase tear evaporation resulting in dry eye symptoms. Failure to blink regularly, such as when staring at a computer screen for long periods, can also contribute to the eyes’ drying.
- Contact Lenses and LASIK. Long-term use of contact lenses can be a factor in the development of dry eyes. Refractive eye surgeries, such as LASIK, can decrease tear production and contribute to dry eyes.
Advanced dry eyes may damage the cornea at the front surface of the eye and impair vision.
Diagnostic Tests for chronic dry eyes
- A comprehensive eye exam. …
- A test to measure the volume of your tears.- Schirmer’s test …
- A test to determine the quality of your tears called Tear Breakup Test…
- A tear osmolarity test. …
- Tear samples to look for markers of dry eye disease, including elevated matrix metalloproteinase-9 or decreased lactoferrin.
An eye exam that includes a complete history of your overall health and your eye health can help your doctor diagnose the cause of your dry eyes.
- Schirmer’s test – A test to measure the volume of your tears. Your doctor may measure your tear production using the Schirmer test.
- The tear breakup test measures the thickness of your tear, also called tear viscosity.
New Advances in dry eye diagnostics. – Tear Osmolarity Test & Rapid Pathogen Screening Test (MMP-9)
Two devices commonly used to conduct objective dry eye testing in many eye doctor’s offices include the Tear Lab Osmolarity System (TearLab, San Diego, CA) and the InflammaDry, Rapid Pathogen Screening test (Rapid Pathogen Screening, Inc, Sarasota, FL). The first is an objective point of care test and can measure a 50-nL tear sample’s osmolarity. The second study analyzes the matrix metalloproteinase 9 (MMP-9) qualitatively in tears. MMP-9 is considered to be a marker for inflammation, usually associated with dry eye.
This research study conducted by Schargus and co-workers that evaluated the MMP-9 in tears and tear film osmolarity in a group of elderly patients (n=20; age = 72.0±6.1yrs) with previously undiagnosed dry eye. The authors also examined the correlation between clinical dry eye tests and MMP-9 in this group of patients. Dry eye symptoms (Ocular Surface Disease Index questionnaire) and signs (tear break-up time, Schirmer test, ocular surface staining) were evaluated in these patients. Enzyme-linked immunosorbent assay [ELISA] test was also used to determine and confirm the concentrations of MMP-9 in tears collected via Schirmer strips.
Patients were classified into four (4) groups: Group A- mild dry eye; Group B, osmolarity difference > 8 mOsm/L between both eyes; Group C- osmolarity cutoff at 308 mOsm/L; Group D >308 mOsm/L).
Conclusion: Eleven percent (11%) of the symptomatic group and 14% of the suspected mild dry eye were positive for MMP-9. ELISA tests confirmed that the InflammaDry MMP-9 tests were accurate. Sixty-seven percent of the symptomatic and 64% of the suspected mild dry eye were positive for tear osmolarity. Tear film osmolarity showed a trend toward correlation with symptoms. In contrast, the quantitative MMP-9 values showed a trend toward correlation with corneal staining. The study concluded that MMP-9 is possibly a late-stage sign that is hardly overexpressed in mild dry eyes. In contrast, tear osmolarity tends to be a more frequent early indicator of ocular surface instability within mild dry eye patients.
How Can TheraLife Help?
TheraLife Eye capsules stimulate the production of normal tears from within. The oral treatment approach results in long-lasting dry eye relief using your own tears.
TheraLife Dry Eye recovery protocol consists of treatment for dry eyes, blepharitis, MGD all at the same time. This comprehensive approach gives us an edge in the field of dry eye treatments.
People who fail eye drops and prescription eye drops come to TheraLife.
To learn more: click here.
The above research information is an abstract from this article.
Schargus M, Ivanova S, Kakkassery V, Dick HB, Joachim S. Correlation of Tear Film Osmolarity and 2 Different MMP-9 Tests with Common Dry Eye Tests in a Cohort of Non-Dry Eye Patients. Cornea. Apr 23, 2015.
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