A refractive error is the most common reason for reduced visual acuity. Myopia, hyperopia, astigmatism and presbyopia belong to the four basic refractive errors and, unfortunately, cannot be prevented. There are different tools to correct them, like spectacles, contact lenses, and refractive surgery. Many different contact lenses are available, the two large groups create rigid contact lenses and soft contact lenses. It is a common knowledge that the presence of a contact lens in the eye divides the tear film into the prelens and postlens tear film layers. In the present study we want to investigate the variability and reproducibility of prelens and postlens tear film thickness measurements.

Inclusion criteria

• Men and women aged over 18 years
• Soft or rigid contact lenses wearers
• Schirmer Test ≥ 10 mm/5 min
• Tear Breakup Time (TBUT) ≥10 seconds

Exclusion Criteria:

• Participation in a clinical trial in the previous 3 weeks
• Presence of any abnormalities preventing reliable measurements as judged by the investigator
• Pregnancy, planned pregnancy or lactating

15 soft contact lens wearers 15 rigid contact lens wearers