Influence of Corvis ® ST on intraocular pressure

Abstract Purpose To investigate the effect of Corvis ST tonometry (CST) on intraocular pressure (IOP). Design Cohort study Subjects Patients with and without primary open angle glaucoma (POAG) were included. Methods. Intervention IOP was measured using the iCare Rebound Tonometer (ICRT) and the biomechanically corrected IOP (bIOP) using the CST. Outcome measure IOP was measured at baseline with ICRT, followed by a CST measurement in one eye with the fellow eye acting as a control. ICRT measurements were repeated at 10 seconds, 1, 2, 4, 8, 15, 30- and 60-minutes in both eyes. The ratio of the IOP of the test to fellow eye was used to control for intra-subject variation. Results Forty subjects (54.09±20.08 years) were included comprising 20 patients with POAG and 20 patients with no ocular abnormalities other than cataract. Mean central corneal thickness was similar in those without (547.4±55.05 μm) and with POAG (520.22±37.59 μm) (p=0.14). There was no significant change in the IOP measured with the ICRT in the fellow eye over the 1 hour period in either the healthy (p=0.87) or POAG group (p=0.92). There were significant changes in the IOP following CST for both healthy (p Conclusion CST causes in a significant reduction in IOP in both glaucomatous and healthy eyes which lasts for at least one hour post.