In vivo confocal microscopic evaluation of corneal langerhans cells in dry eye patients.

PURPOSE: To assess inflammatory involvement of cornea in dry eye by means of confocal microscopy, evaluating the presence and distribution of Langherans cells (LCs). METHODS: 98 eyes of 49 subjects were enrolled: 18 subjects affected by Sjögren Syndrome Dry Eye (SSDE), 17 with Non-Sjögren Syndrome Dry Eye (NSSDE), 14 healthy volunteeers. Dry eye symptoms, tear film, ocular surface damage and corneal confocal microscopy were analized. RESULTS: A significant increase of LCs density was observed at sub-basal nerve plexus (SSDE = 79 cells/mm(2) andNDE = 22 cells/mm(2); p = 0,0031) and sub-epithelial nerve plexus (SSDE = 38 cells/mm(2) and NDE = 3 cells/mm(2); p = 0,0169) in central cornea of SSDE group. An increased number of LCs from the center to the periphery of the cornea was observed, significant only in healthy volunteers group. In dry eye patients there was an increase in LCs density in both peripheral and central cornea with a significant difference between NDE (14,66 cells/mm(2)) and SSDE (56,66 cells/mm(2)) only in central cornea (p = 0,0028). In SSDE group, mean density of LCs in central cornea results also superior to NSSDE group (29,33 cells/mm(2)). There was no correlation between LCs density and dry eye symptoms, tear film deficiency and ocular surface damage. CONCLUSION: This study demonstrates the activation of an inflammatory and immunological reaction in cornea of NSSDE and SSDE patients. Confocal microscopy can be an important diagnostic tool in evaluation and follow-up of dry eye disease.

Ocular surface alterations and topical antiglaucomatous therapy: a review.

Ocular Surface Disease (OSD) is prevalent among medically treated patients with glaucoma. This is basically related to three key-points: OSD and glaucoma are both prevalent in elderly and are common comorbidities in the same patient; the role of the active ingredient of the medical antiglaucomatous therapy; the role of the preservative agent of this medical therapy. Considering the actual state of literature we can state that the active glaucoma agent have a role in OSD, but the main cause seems to be the preservative agent, in particular referring to benzalkonium chloride, BAK. In the clinical evaluation of dry eye patients there is no actually established gold standard. Since the ocular surface injury not only causes dry eye, red eye, eye itching, photophobia and other discomforts, but also increases the risk of failure of glaucoma surgery in patients, it becomes fundamental a complete and good clinical evaluation of OSD (considering Schirmer's test, tear breakup time, corneal and conjunctival staining) together with a good evaluation of patients' quality of life (with validated questionnaires). Development of complex preparations, preservative-free and/or novel preservative preparations for glaucoma therapy could provide a promising approach in the prevention of ocular surface injuries.