Please select the eligibility criteria that correspond to the clinical trial below.
Title: A Prospective Study to Establish Normative Values, Demographic Variations, Referent Diagnostic Values and Disease Severity Correlations for Dry Eye Disease and TearLab Osmometry.
Brief Summary: This is a prospective, observational case series to determine the clinical utility of tear osmolarity and other commonly used objective tests to diagnose dry eye disease, as well as to establish referent values for objective tests of the disease.


Options:
A: Inclusion Criteria:

* Be between the ages of 18 and 79 years of age.
* Must understand and be able, willing and likely to fully comply with study procedures and restrictions.

Exclusion Criteria:

* Clinically significant eyelid deformity or eyelid movement disorder that is caused by conditions such as notch deformity, incomplete lid closure, entropion, ectropion, hordeola or chalazia..
* Previous ocular disease leaving sequelae or requiring current topical eye therapy other than for Dry Eye Disease, including, but not limited to: active corneal or conjunctival infection of the eye and ocular surface scarring.
* Active ocular allergy.
* LASIK or PRK surgery that was performed within one year of Visit 1.
* Started or changed the dose of chronic ocular medication within 30 days of visit 1.
* Contact lens worn within the past eight (8) hours.
* Any ophthalmologic drops within 2 hours of screening and visit 1 procedures.
* Pregnancy or lactation.
* Abnormality of nasolacrimal drainage (by history).
* Punctual plugs placement or cauterization within 30 days of Visit 1
* Started or changed the dose of chronic systemic medication known to affect tear production including, but not limited to antihistamines, antidepressants, diuretics, corticosteroids or immunomodulators within 30 days of Visit 1.
* Systemic disease known to affect tear production or loss including, but not limited to thyroid eye disease, that has been diagnosed or has not been stable within 30 days of Visit 1.
* Known hypersensitivity to any of the agents used in testing i.e. sodium fluorescein, lissamine green, oxybuprocaine or proparacaine.
B: Inclusion Criteria:

1. Eyelids must present with blocked meibomian gland openings (plugs), at least 1 visible MG plug in the 4 eyelids, or discernable change in consistency of meibum (increased in viscosity or opacity) when MG expressed in upper or lower eyelids.
2. At least one out of 8 questions on dry eye symptoms is answered with often or all the time.
3. Eyes should not show any other ocular surface pathology which required more treatment than eye lubricant and conventional eyelid hygiene.

Exclusion Criteria:

1. Known history of thyroid disorders (diagnosed by physician).
2. No ocular surgery within the previous 6 months and LASIK within the previous 1 year.
3. Any intake of central nervous system and hormonal drugs within last 30 days and inability to withhold such drugs for at least 6 weeks.
4. Active ocular infection or pterygium.
5. Anticipated necessity to wear contact lens in the duration of the study.
6. Living in the same household as another participant of the study.
7. Any other specified reason as determined by clinical investigator, for example, the need to use any treatment or eyedrops not permitted by the study.
C: Inclusion Criteria:

* Eyelids must present with blocked meibomian gland openings (plugs), at least 1 visible MG plug in the 4 eyelids, or discernable change in consistency of meibum when MG expressed in upper or lower eyelids.
* At least one out of 8 questions on dry eye symptoms is answered with often or all the time (Appendix C, Questionnaire modified after Schein et al.,1997).
* Eyes should not show any other ocular surface pathology which required more treatment than eye lubricant and conventional eyelid hygiene.

Exclusion Criteria:

* Known history of thyroid disorders (diagnosed by physician).
* No ocular surgery within the previous 6 months and LASIK within the previous 1 year.
* Any intake of central nervous system and hormonal drugs within last 30 days and inability to withhold such drugs for at least 6 weeks.
* Active ocular infection or pterygium.
* Anticipated necessity to wear contact lens in the duration of the study.
* Living in the same household as another participant of the study.
* Any other specified reason as determined by clinical investigator, for example, the need to use any treatment or eyedrops (eg. Restasis) not permitted by the study.
D: Inclusion Criteria:

* All patients with meibomian gland dysfunction requiring treatment (defined below),
* who have given their written consent to the study.
* Meibomian gland dysfunction requiring treatment is classified by us as:
* Speed score\> 7, Lipiview \<61 nm, MGE \<5 of 15 open glands

Exclusion Criteria:

* Excluded are patients who, due to other diseases would not be able to fulfill the follow-up appointments or give an informed consent to the study
* Systemic medication with tetracyclin derivatives, antihistamines, isotretinoin, or nutritional supplements for MGD that started \<3 months before baseline examination
* Topical cyclosporine-A or steroids that started \<1 month before baseline examination
* Ocular surgery or trauma \<3 months before baseline examination
* Any eyelid abnormalities
* Systemic diseases resulting in dry eye.

Answer: A