The purpose of this study is to assess eyelid margin staining, termed "lid wiper epitheliopathy" (LWE), in three populations. The hypothesis is LWE will be more prevalent in symptomatic contact lens wearers than non-symptomatic contact lens wearers and least prevalent in asymptomatic non-contact lens wearers.

Inclusion Criteria:

• Has full legal capacity to volunteer;
• Has read and signed an information consent letter;
• Is willing and able to follow instructions and maintain the appointment schedule;
• Has had an ocular examination in the last two years;
• Has clear corneas and no active ocular disease;
• Other protocol-defined inclusion criteria may apply.

Exclusion Criteria:

• Has any ocular disease;
• Has a systemic condition that may affect a study outcome variable;
• Is using any systemic or topical medications that may affect ocular health;
• Has known sensitivity to the diagnostic pharmaceuticals to be used in the study;
• Has undergone corneal refractive surgery;
• Currently wears contact lenses on an extended wear basis (overnight);
• Has any clinically significant lid or conjunctival abnormalities, neovascularization, corneal scars or corneal opacities;
• Other protocol-defined exclusion criteria may apply.

Participants will be identified and screened by the University of Waterloo in Ontario, Canada.