The Short-Term Effect of Prostaglandin Analog Monotherapy on Corneal Biomechanical Properties in Normal Tension Glaucoma Patients

Purpose: To evaluate the effects of short-term prostaglandin analogues treatment on the corneal biomechanics of patients with normal tension glaucoma. Methods: This study included 52 eyes of 52 patients who were diagnosed with normal tension glaucoma. All patients were divided into two groups; one group (27 eyes) received tafluprost while the other group (25 eyes) received travoprost. Intraocular pressure, Biomechanical properties were measured by using goldmann applanation tonometer, ocular response analyzer before treatment and at 8-week after treatment. Results: The mean decrease in intraocular pressure, Goldmann-correlated IOP (IOPg), corneal-compensated intraocular pressure by using Goldmann applanation tonometer, and Ocular response analyzer were statistically significant in total patients, tafluprost, and travoprost group after using prostaglandin analogues (p < 0.001, p < 0.001, p < 0.001, respectively). Corneal hysteresis showed no statistical differences after treatment in total, tafluprost and travoprost group but corneal resistance factor (CRF) showed statistically significant decrease after using prostaglandin analogues in total, tafluprost, and travoprost group (p < 0.001, p = 0.025, p < 0.001). Upon multivariate analysis, the higher initial IOPg and the lower initial CRF checked, the variation of CRF (CRF in baseline - CRF at 8 weeks) got higher (beta = 0.134, p = 0.017). Conclusions: It is needed to carefully monitor and evaluate the effects of prostaglandin analogues on intraocular pressure associated with initial intraocular pressure and the changes of CRF after prostaglandin treatment in normal tension glaucoma patients. CRF is sensitive factor to short-term changes of intraocular pressure after prostaglandin analogues treatment, and it is required to consider the properties of CRF when we evaluate between progression of glaucoma and corneal biomechanical properties.