Changes in corneal endothelial cell shape after treatment with one drop of ROCK inhibitor

We performed an investigation of the temporal impact on corneal endothelial cell (CEC) shape after ophthalmic instillation of one drop of the ROCK inhibitor, ripasudil.

Subjects comprised 32 healthy adult volunteers, each of whom instilled ripasudil in the right eye. CEC shape [defined as CEC density (CECD), coefficient of variation (CV), and hexagonal cell rate (6A)], central corneal thickness (CCT), intraocular pressure (IOP), and conjunctival hyperemia were evaluated before instillation (baseline) and at 15 min, 1 h, 2 h, and 4-6 h after instillation by non-contact specular microscopy and slit-lamp microscopy. The incidence of pseudo gutta was also assessed.

The CECD (cells/mm²) significantly decreased after instillation as follows: 2661 cells/mm² at baseline, 2578 cells/mm² at 15 min, 2527 cells/mm² at 1 h, 2575 cells/mm² at 2 h, and 2613 cells/mm² at 4-6 h. After instillation, CV significantly increased and 6A significantly decreased. Pseudo gutta appeared in 18 subjects (56.3%) after instillation. There was no difference in CCT before and after instillation. IOP significantly decreased after instillation. The most severe conjunctival hyperemia was observed at 15 min after instillation, but had nearly disappeared within 2 h.

Pseudo gutta appeared in more than half of the subjects, and the CEC shape changed upon instillation of one drop of ripasudil; however, it recovered at 4-6 h after instillation. Therefore, these changes would not greatly impact clinical treatment. Similar to the presence of conjunctival hyperemia, changes in CEC shape occur at early stages after instillation of ripasudil.