Contact Lens-Associated Dry Eye Disease: Recent Advances Worldwide and in Japan

Contact lens wearers complain of various types of contact lens discomfort (CLD), which may result in the discontinuation of contact lenses. CLD is often associated with dry eye disease. A contact lens divides the tear film into two layers: the pre- and post-lens tear film. This change leads to instability of the pre-lens tear film, thinning of pre- and post-lens tear film thickness, and increased friction between the contact lens and the ocular surface. The Japanese Dry Eye Society recommends the diagnosis of tear film abnormality first (tear film-oriented diagnosis [TFOD]) and the treatment of dry eye disease based on TFOD (tear film-oriented therapy [TFOT]). These concepts can be applied for contact lens-associated dry eye disease (CLADE). Noninvasive tear film breakup time, tear volume evaluation, vital staining, and assessment of Meibomian glands are performed to evaluate the tear film. On vital staining analysis of CLADE, lid wiper epitheliopathy and conjunctival edge staining are major findings. In TFOT of CLADE, secretagogues of water or mucins, such as diquafosol and rebamipide, have been first used in Japan. Material, design, wettability, and friction coefficient of the contact lens could affect CLADE. Changes of contact lens may be an option in TFOD. However, the effects of contact lens properties on the tear film and ocular surface are still unclear. Further controlled studies are needed in the future.