In vivo distribution of corneal epithelial dendritic cells in patients with glaucoma

PURPOSE: The purpose of this study was to evaluate dendritic cell (DC) distribution, morphology, and DC density in the entire cornea of medically controlled glaucoma patients (MCGP), using in vivo confocal microscopy (IVCM). METHODS: Fifty MCGP were enrolled, 15 patients with dry eye, and 15 healthy subjects served as controls. Patients were asked to complete the Ocular Surface Disease Index (OSDI) questionnaire and then underwent tear film break-up time (BUT), corneal staining, and Schirmer test (ST) I and then IVCM. In vivo confocal microscopy evaluated the limbal and central DC density, the DCs morphology and distribution. Relationships among DC density, OSDI score, and corneal staining were analyzed. RESULTS: Medically controlled glaucoma patients were divided into 2 groups; group 1 (29 eyes) was tested with one drug; group 2 (21 eyes) was tested with ≥2 drugs. Dendritic cells were significantly higher at limbus than at central cornea in both groups. Limbal DCs were found in the 86.7%, 89.7%, 90.4%, and 93.3% of eyes in controls, groups 1 and 2, and DED; central corneal DCs were found in the 26.6%, 75.9%, 80.9%, and 86.6% of eyes in controls, groups 1 and 2, and DED. Dendritic cell density was higher in glaucoma groups and DED than in controls (P < 0.001). Group 2 and DED presented DC density significantly higher compared with group 1 (P < 0.05). In group 1 DC density was higher in patients taking preserved drugs than in those taking preservative-free drugs (P < 0.05). Dendritic cell density was higher in DED than in group 2 (P < 0.05). Dendritic cell density significantly correlated with corneal staining and OSDI (P < 0.001). CONCLUSIONS: Dendritic cells increase in the entire cornea of MCGP, with a higher density at limbus. These modifications may take part in the induction of the glaucoma-related ocular surface disease.