Non-invasive Ocular Surface Measurements Before and After Interventions

Inclusion Criteria: * Individuals with dry eye diagnoses (aqueous deficient dry eye \[ADDE\], and/or evaporative dry eye), dry eye symptoms (as associated with Sjogren's Syndrome diagnosis), refractive surgery, contact lens use, and exposure to dry work environments are appropriate to correlate clinical tests, subjective responses and objective measurements of current ocular surface status and to study clinically-recommended or patient-directed dry eye treatments such as taking dietary supplements, wearing moisture-retaining goggles, performing lid massage, or using over the counter eye drops or artificial tears. * Individuals who do not currently have dry eye symptoms but who may be at risk for dry eye diagnosis, and those who have dry eye symptoms but no clinical dry eye diagnosis, are of interest to correlate clinical tests, subjective responses and objective measurements of current ocular surface status and, if symptoms appear or worsen, to correlate the data with the effect of environmental condition changes, such as increasing the humidity or reducing air flow, on the ocular surface. * Individuals who have undergone ocular surgery are at increased risk for dry eye. While some subjects who have had ocular surgery may never develop dry eye symptoms because they have an adequate reserve of tear production, others may develop symptoms as a result of the disruption of the ocular surface, including the anatomy and nerves. Subjects who have had surgery or procedures and are no longer being provided with direct post-operative care may participate in the study. Routine follow-up post- operative care does not disqualify subjects from participation. Subjects who are receiving post-operative care must obtain approval of their clinician to participate in the study. * Individuals who have eye conditions that affect the shape or condition of the cornea, such as individuals with keratoconus. * Experienced contact lens wearers are appropriate for studies that use their own lenses (soft, rigid gas permeable \[RGP\], hard \[PMMA\]) or the same type of lens within the FDA approved modality (daily, continuous or extended wear) and replacement cycle (for example, daily, one week, one month, etc.) as described in the lens package insert and/or prescribed by their eye care provider to investigate ocular surface data before, during and after lens use. * Normal individuals, those without a dry eye diagnosis, without dry eye symptoms or those who do not wear contacts to act as controls for the focus areas in the studies. Exclusion Criteria: Individuals with eye or medical condition(s) that contraindicate performing screening or measurements will not be eligible for this study. Specific examples include: * Individuals will not be dilated if an exam and/or medical history indicted they have a narrow anterior chamber angle, glaucoma, or other contraindications to dilation (like arterio-sclerotic cerebrovascular disease). * Individuals with the following will not participate in contact lens studies: presence of ocular or systemic allergies or disease (infection), clinically significant (grade 3 or 4) corneal edema, corneal vascularization, or any other abnormalities of the cornea, tarsal abnormalities or bulbar injection or use of medication that might interfere with contact lens wear. * Individuals will not participate in any aspect of the study if: they are pregnant or become pregnant or are lactating, have an infectious disease (e.g. hepatitis, tuberculosis) or have an immuno-suppressive disease (e.g. HIV). * Individuals with known sensitivity to dyes or to numbing drops will not be screened using these agents. * Individuals who wear dental braces cannot be involved in the measurements in which a dental impression/bite bar is required. The impression material will stick to the braces. Individuals with very sensitive teeth or loose dentures may have difficulty making the dental impression.