Assessment of corneal thickness and tear meniscus during contact-lens wear

• Central and mid-peripheral corneal thickness, and tear meniscus volume were assessed during contact lens wear.
• An ocular coherence tomography based device was used for the evaluation.
• Seven daily disposable contact lenses were studied, plus the naked eye scenario.
• No clinically significant differences were encountered in corneal thickness.
• The tear meniscus volume did drop significantly with some of the contact lens.

PurposeTo assess the effect of seven different daily disposable contact lenses upon corneal thickness, as well as upon tear meniscus volume, by using optical coherence tomography (OCT).MethodsThirty-four young healthy subjects wore seven different types of daily disposable soft contact lenses, each for a period of 12 h: Delefilcon A, Nelfilcon A, Omafilcon A, Filcon II3, Narafilcon A, Etafilcon A and Hilafilcon B. Central and mid-peripheral corneal thickness and lower tear meniscus volume (TMV) were measured using an OCT device during contact-lens wear at 4-h intervals throughout a 12-h period. Measurements were also recorded without any contact lenses being worn during a day.ResultsIn the no-lens scenario a small but significant (p < 0.05) thinning in the cornea was observed after the 12-h period. Overall, as for contact-lens wear, it was the Hilafilcon B lens that caused the greatest thickness increase in the central area, whereas the Etafilcon A caused it in the mid-peripheral cornea. Delefilcon A was the lens that showed the most similar behavior to the naked eye. As for TMV, it decreased with all the lenses, but it was the Delefilcon A lens the one that caused the smallest drop in TMV (p = 0.007).ConclusionsOCT makes it possible to evaluate both corneal thickness variations and TMV changes as a result of contact-lens wear. The changes in corneal thickness hereafter presented are not clinically significant. On the other hand, TMV drop could indicate discomfort for contact-lens users.