Differences in Corneal Structure and Function in Patients With Sjogrens vs. Non-Sjogrens Dry Eye

Inclusion Criteria: * Male or female aged 18 or older * Capacity to give informed consent * Self-reported literacy * Best corrected visual acuity at distance 20/40 in each eye * Signed Institutional Review Board (IRB)-approved consent agreeing to the terms of the study For Sjogren's-related dry eye, the below inclusion criteria will be required * a previous diagnosis of dry eye made by an eye care specialist * a previous diagnosis of Sjogren's made according to the 2016 revised Sjogren's classification criteria Exclusion Criteria: * ● Age less than 18 years * Physical or mental issues, illiteracy, or language problems that might possibly interfere with reading ability or other condition that would preclude successful participation in this study * Contact lens wear within 10 days of enrollment * Any intraocular surgery (including cataract surgery) within the last 3 months * Any minor ocular surgery including tear duct cauterization or plugs within the last 30 days * Any history of corneal surgery (including LASIK/PRK) or cosmetic lid surgery in the past 12 months * Any history of glaucoma surgery (e.g., trabeculectomy or a tube shunt) * Best corrected vision worse than 20/40 * Known history of severe ocular surface disease that might cause corneal haze and interfere with corneal staining score including but not limited to graft-versus-host disease, mucous membrane pemphigoid, atopic keratoconjunctivitis * Presence of keratoconus * Concurrent epithelial corneal disease or dystrophy (e.g., anterior basement membrane disease, pterygium, or scarring) that might affect the corneal staining score * Previous use of OXERVATE® for neurotrophic keratitis * Neurotrophic keratoconjunctivitis or corneal/conjunctival scarring (history of herpes simplex virus or varicella zoster virus keratitis) * Any blepharitis eyelid procedures such as Intense Pulsed Light (IPL), low level light treatment therapy, LipiFlow®, or nasolacrimal duct probing in the last 30 days prior to the study visit * Any acupuncture or physical therapy on the face or head within the past 3 months * Current smoker (within the past year) * Pregnant or nursing * Artificial tear use within 2 hours of study visit * Topical ophthalmic non-steroidal anti-inflammatory drug use 24 hours before the study visit * History of taking or current use of topical glaucoma drops or neurostimulation drugs or devices for treating dry eye * History or current intravitreal injections for macular degeneration * History of continuous positive airway pressure usage in the past 3 months * Any concurrent medical condition that in the judgment of the PI might interfere with the conduct of the study, confound the interpretation of the study results.