RGP lens wearers show eye blink variations with 3 o'clock, 9 o'clock staining

While experiencing 3 o'clock and 9 o'clock staining, rigid gas permeable contact lens wearers exert more eye blinking attempts and demonstrate fewer complete eye blinks and more incomplete eye blinks compared with lens wearers with minimal staining and non-lens wearers, according to a study. Contact lens fit and corneal coverage may influence these incomplete eye blinks.

Eef van der Worp, BSc, FAAO, and colleagues evaluated variations in frequency and completeness of eye blinks during a 5-minute period among 30 rigid gas permeable contact lens wearers experiencing 3 o'clock and 9 o'clock corneal fluorescein staining. They compared results with variations observed in 25 RGP lens wearers with less than grade 1 corneal staining and 26 controls who were not lens wearers.

All eye blinks were categorized as either complete, incomplete or an attempt. The investigators also assessed type of lens fit, lens-to-cornea fit, spherical equivalent of refraction and corneal coverage. The study results are published in the September issue of Optometry and Vision Science.

The investigators found no differences in eye blink frequencies between the three groups.

However, they observed fewer complete eye blinks, more incomplete eye blinks and more eye blink attempts in eyes experiencing 3 o'clock and 9 o'clock staining (P < .01) than in eyes without substantial staining (P = .03) and in non-lens wearers (P < .01).

Eyes with interpalpebral lens fits demonstrated fewer complete eye blinks while exerting more eye blink attempts than eyes with lid attachment lens fits (P < .01 for both).

In addition, eyes wearing large or optimally sized lenses demonstrated fewer complete eye blinks (P = .02) and more incomplete eye blinks (P = .03) than eyes wearing small lenses, according to the study.