Agreement of Two OCT Biometers: A Pilot Study

Inclusion Criteria: * Have healthy, clear corneas for the normal cohort; * Have documented keratoconus for the keratoconus cohort; * Have reported use of daily contact lens use for the contact lens cohort; * Have documented dry eye, consisting of signs and symptoms for the dry eye cohort; * Has had previous keratorefractive surgery for the post-refractive surgery cohort; * Able to comprehend and sign the informed consent form. Exclusion Criteria: * Active ocular infection or inflammation; * Unable to fixate due to nystagmus or other eye movement abnormality (e.g., significant strabismus); * Any ocular disease and/or condition that, in the investigator's clinical judgment, may put the subject at significant risk, may compromise study result or may interfere significantly with the subject's participation in the study.