Effect of topical prostaglandins on the biomechanics and shape of the cornea.

PURPOSE: To investigate the effect of topical prostaglandin (PG) eyedrops on the biomechanics and shape of the cornea.

METHODS

Consecutive patients with primary open-angle glaucoma who had been treated with the same anti-glaucoma PG (114 eyes, 57 patients) or β-blocker (36 eyes, 18 patients) eyedrops in 1 eye alone for more than 3 months at Inouye Eye Hospital or Miyata Eye Hospital. The biomechanical properties of the cornea were measured using a Corvis ST device (Oculus, Wetzlar, Germany). Corneal tomography was measured with a Casia 1 or 2 (Tomey Corp., Nagoya, Japan). The biomechanical parameters and tomographic features of the cornea were compared between PG-treated eyes, β-blocker-treated eyes, and contralateral eyes using a mixed-effect model adjusted for intraocular pressure and corneal thickness and a linear model adjusted for age, sex, intraocular pressure, and corneal thickness.

RESULTS

The PG-treated eyes had a significantly smaller applanation 1 time, the highest concavity radius, and a larger deformation amplitude than the contralateral eyes. Also, the PG-treated eyes had a significantly smaller applanation 1 time and applanation 2 velocity but a larger peak distance than the β-blocker-treated eyes. There were no significant differences in any of the Casia parameters between the PG-treated eyes and the contralateral eyes.

CONCLUSION

The results of this study suggest that topical PG makes biochemical changes to the cornea but does not alter its shape.