Influence of Topical Medication on Corneal Biomechanics in Primary Open-Angle Glaucoma

The aim of this study was to investigate whether long-term topical application of intraocular pressure (IOP) lowering medication has an effect on corneal biomechanical properties in primary open-angle glaucoma (POAG).

This study included 225 White European patients with POAG. Biomechanical measurements were performed using the Scheimpflug analyzer Corvis ST. Each patient underwent a detailed medical history, an ophthalmic examination, and a 24-hour IOP profile. Further examinations were performed using Heidelberg retinal tomography, endothelial cell microscopy, and Pentacam. The results were compared with a group of 78 healthy subjects matched for age, pachymetry, and IOP.

Most dynamic corneal response parameters showed significant differences between patients with POAG and healthy subjects. When comparing patients with POAG with and without the use of prostaglandin analogs (PGAs), differences were observed in second applanation deflection length (P = 0.002), second applanation deflection area (P = 0.001), and deformation amplitude ratio max 1 mm (P = 0.001). In contrast, the use of beta-blockers, carbonic anhydrase inhibitors, alpha agonists, and miotics led to hardly any changes in corneal biomechanics.

Long-term use of PGAs is not only associated with a reduction in corneal thickness but also may affect the biomechanical properties of the cornea.