A US study is looking at tears to discover the impact of contact lenses on the general health of the eye.
Volunteers are wearing silicone hydrogel contact lenses while researchers at the University of Alabama at Birmingham"s School of Optometry study cytokines in their tears.
Cytokines are a type of protein and can shed light on eye health.
There are 80 volunteers involved, who were trained to collect their tears in small tubes.
Lead researcher Lucy Kehinde said that early results have shown that patients can find out about what type of contact lenses suit them from even small changes.
Another study of contact lenses, by Anja Kissner, has found that wearing soft contact lenses does not change corneal measurements, even long-term.
Her findings, which she presented to the Association for Research in Vision and Opthalmology meeting, were reported by OSN Super Site.
She had looked at measurements such as central corneal thickness.
by Alexa Kaczka