Tear film analysis assesses the quantity, quality, and stability of the tear film that coats the eye surface. It is central to diagnosing and managing dry eye disease.
Components
Tests may measure tear volume, osmolarity, evaporation rate, lipid layer quality, and inflammatory markers. Imaging of tear meniscus height and interferometry of the lipid layer are commonly used.
- Non-invasive methods include interferometry and meniscus height measurement
- Invasive tests such as Schirmer strips and dyes assess production and distribution
- Questionnaires often accompany objective assessments to capture symptoms
- Results can be combined into severity grading schemes
Clinical Use
Tear film analysis helps differentiate aqueous-deficient from evaporative dry eye and guides targeted treatment. It also monitors response to therapy.
- Osmolarity and inflammatory markers can indicate disease activity
- Changes in tear stability correlate with patient comfort and vision quality
- Regular assessment is useful in chronic management
- Findings should be interpreted alongside ocular surface staining and lid examination
