The TearLab Osmolarity System is the first objective and quantitative test for diagnosing and managing Dry Eye patients. It measures the salt content (osmolarity) of your tears to aid in the diagnosis of dry eye, in conjunction with other clinical assessments.
Tear osmolarity has been shown to have the best predictive value* for diagnosing Dry Eye Disease of any single test. Its chip technology tests a tiny sample of your tears to measure its salt content and the osmolaity number gives us a meaningful measure of the health and stability of your tear film.
*Information is extracted from TearLab official website at http://www.tearlab.com/.
Tear film Analysis
According to the International Dry Eye Workshop, dry eye disease is a “multifactorial disease of the tears and ocular surface that results in symptoms of discomfort, visual disturbance, and tear film instability. It is accompanied by increase osmolarity of the tear film and inflammation of the ocular surface.”
With increased osmolarity of the tear film, the tear film less stable. We use the Placido disc videokeratology to measure the tear film stability. This is an automated and non-invasive way of measuring the tear film surface quality breakup time as a clinical marker for diagnosing dry eye disease.
As shown in the video, the non-dry eye result has an even colour throughout the video while the dry eye result had various colours showing up. The instability of the tear film is shown using the warmer colours. The breaking up of the cooler colours signify the breaking up of the tear film.
Studies have shown that automated measurement of the tear film surface quality breakup time is repeatable and non-invasive. It also has a high sensitivity and specificity to tear hyperosmolarity, which is a key feature of dry eye disease.