Changes in Corneal Biomechanics and Intraocular Pressure Following Cataract Surgery

PURPOSE: To investigate the effects of cataract surgery on corneal biomechanics and intraocular pressure (IOP) measured with the updated Corvis ST tonometer (CST). DESIGN: Prospective, interventional case series study. METHODS: This study included 39 eyes of 39 cataract patients. CST measurements were performed at presurgery (Pre) as well as 1 week (1W), 1 month (1M), and 3 months (3M) postsurgery. The following CST parameters were recorded: deformation amplitude max (DA max), DA ratio max 1 mm and 2 mm, integrated radius, stiffness parameter at applanation 1 (SP A1), Ambrosio relational thickness to the horizontal profile (ARTh), Corvis biomechanical index (CBI), central corneal thickness (CCT), noncorrected intraocular pressure (IOPnct), and biomechanically corrected IOP (bIOP). IOP was also measured with Goldmann applanation tonometry and the noncontact tonometer CT-90A. All measurements were compared at each period using the linear mixed model, with and without adjustment for bIOP and CCT. RESULTS: All IOP measurements decreased over time (P < .01). CCT was increased at 1W and 3M (P < .01), whereas ARTh was decreased at 1W and 1M (P < .01), but returned to its Pre level at 3M. DA max and Integrated radius were increased at 3M (P < .01), whereas SP A1 was decreased at 3M (P < .01). CBI was increased at 1W (P < .01), but returned to its Pre level at 1M. CONCLUSIONS: IOP and Corneal biomechanical properties are changed after cataract surgery. In particular, SP A1 decreases while DA max and integrated radius increase, even at 3M, suggesting a less stiff cornea. (C) 2018 Elsevier Inc. All rights reserved.