Corneal Parameters at Confocal Microscopy in Glaucoma Patients and Normal Subjects

Purpose:To evaluate the corneal parameters with confocal microscopy in glaucoma patients and normal subjects. Methods:23 consecutive patients with primary open-angle glaucoma and 22 age and sex-matched untreated controls underwent confocal microscopy of the cornea using HRT II (Heidelberg Retinal Tomograph) cornea module. Glaucoma patients had an IOP less than 21 mmHg with medical treatment for at least two years before inclusion; two subgroups of treatments were considered: beta-blockers and prostaglandin analogues. The following corneal parameters were evaluated: endothelial cell density; number, reflectivity and tortuosity of subbasal nerves. For reflectivity and tortuosity, dedicated grading scales ranging from 0 to 4 were used (Oliveira-Soto, Cornea. 2001). Mean values in the two groups were compared by means of two-tailed t-test for unpaired data; in the glaucoma group, differences between treatments were also evaluated. Results:The results are summarized in the Table Conclusions:Glaucoma patients show lower endothelial density, lower nerve density and reflectivity and higher tortuosity when compared to controls; no significant difference was found between treatments. Further investigations are required to address the causes of the differences found in our dataset; if confirmed, these corneal features in glaucoma patients should be taken in due consideration, particularly in patients with long-standing IOP-lowering treatments and in candidates to surgery.