Influence of cyclopentolate hydrochloride on corneal biomechanical properties in healthy individuals.

Objective: This observational study aims to investigate the effects of cyclopentolate hydrochloride (1%) on corneal biomechanical properties, with the ocular response analyzer (ORA), in healthy individuals. Methods: Corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg), and cornealcompensated intraocular pressure (IOPcc) measurements of 36 (15 female and 21 male) healthy individuals, before and after 45 min of 1% cyclopentolate hydrochloride instillation, were performed by the ORA. Results: The mean CH and IOPcc measurements of the eyes were 10.6361.17 mm Hg and 15.1562.69 mm Hg, precycloplegia, and 11.0961.32 mm Hg and 14.1662.77 mm Hg, postcycloplegia, respectively. The differences between the precycloplegia and postcycloplegia in both measurements were statistically significant (P=0.031, P=0.016, respectively; paired t test). The mean CRF and mean IOPg measurements of the eyes were 10.4061.16 mm Hg and 14.8362.56 mm Hg, precycloplegia, and 10.6161.33 mm Hg and 14.2562.65 mm Hg, postcycloplegia, respectively. The differences between the precycloplegia and postcycloplegia measurements of the eyes were insignificant (P=0.264 and P=0.100, respectively; paired t test). Conclusions: A 1% cyclopentolate hydrochloride instillation leads to significant changes in the CH values and IOPcc measurements. This should be taken into account during the evaluation of refractive surgery candidates and in clinical conditions where ORA measurements are considered in the diagnosis and follow-up.