Confocal Microscopic Variations In Aqueous Tear Deficient And Evaporative Dry Eyes

To determine confocal microscopic variations in aqueous tear deficient and evaporative dry eyes and compare them with healthy eyes.

This observational, case-control study was carried out at Mugla Sıtkı Kocman Training and Research Hospital Department of Ophthalmology in Muğla.

We evaluated patients who had irritated, gritty, scratchy or burning eyes.Tear break-up time ( TBUT ), Schirmer's test without anesthetic, corneal staining were applied.Patients with dry eyes were divided into two groups as aqueous  tear deficient (Group 1) (Schirmer's test score < 5 mm, TBUT < 10 sec, with a history of Sjogren's syndrome and without meibomian gland dysfunction) and evaporative (Group 2) ( Schirmer's test score > 10 mm, TBUT < 10 sec, without a history of Sjogren's syndrome and with meibomian gland dysfunction) subtypes. Patients with healthy eyes ( Schirmer's test score > 15 mm, TBUT > 10 sec, without any dry eye symptoms) were enrolled as the control group. Forty-four,42,40 eyes were included in Group 1, 2, control group.

The epithelium cellular density was significantly different among the groups(p<0.001,p<0.001). Group 1 had the highest superficial and lowest basal epithelium cellular density.The mean anterior and posterior keratocytes density showed significantly different results (p=0.032, p=0.035). Group 1 had the highest of them.The mean size, density, and number of corneal dendritic cells were significantly higher in Group 1(p<0.001 for all parameters). Subbasal nerve fiber number density was significantly decreased in Group 1 compared to Group 2 and the control group (p=0.09, p<0.001; respectively). Endothelial cell density was significantly decreased in Grop 1 and Group 2 compared compared to the control group (p=0.020,p=0.015)

This study showed that corneal confocal microscopic parameters were primarily affected in aqueous tear deficient dry eyes. IVCM can be used to understand better which part of the cornea is mostly affected in various types of dry eyes.

The authors have no conflicts of interest to disclose