[The effect of topical glaucoma therapy on the corneal subepithelial layer]

Glaucoma is one of the most common causes of vision loss worldwide. In Russia, more than 1 million patients with glaucoma were registered in 2022, including more than 100 000 patients with newly diagnosed glaucoma. Detection of early-stage glaucoma has improved in Russia thanks to the development of high-precision diagnostic methods.

The study aimed to assess the effect of topical therapy on the structure of corneal nerve fibers and on the status of Langerhans cells using two-way analysis of variance.

The study included 102 elderly individuals (204 eyes). The observation group consisted of patients diagnosed with stage I-III primary open-angle glaucoma (POAG) receiving conservative glaucoma treatment (n=73, 146 eyes), and the comparison group consisted of ophthalmologically healthy volunteers (n=29, 58 eyes). Patients with a history of laser or surgical interventions on the eye were excluded from the study. Laser confocal microscopy was performed using an HRT III device with Rostock Cornea Module (Heidelberg, Germany). The obtained confocal images were analyzed using the authors' original software program Liner 1.2 S.

The results of analysis of variance showed a statistically significant effect of glaucoma stage on neuroretinal rim area. The eye drop use had an insignificant effect on the relationship between glaucoma stage and the anisotropy coefficient of corneal nerve fiber orientation. We found no statistically significant relation between the anisotropy coefficient of corneal nerve fiber orientation and the number of Langerhans cells in the subbasal corneal nerve plexus layer between the groups that used eye drops and those that did not.

In patients with glaucoma, corneal confocal microscopy findings may be informative, with particular attention warranted to the anisotropy coefficient of corneal nerve fiber orientation and the status of Langerhans cells.