Corneal biomechanical properties and intraocular pressure changes after phacoemulsification and intraocular lens implantation

PURPOSE: To evaluate corneal viscoelastic and intraocular pressure (IOP) changes measured by an ocular response analyzer (ORA) after phacoemulsification and intraocular lens (IOL) implantation. SETTING: Yeditepe University Department of Ophthalmology, Istanbul, Turkey. METHODS: Fifty-one eyes scheduled for cataract surgery were included in the study. Corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated intraocular pressure (IOPcc), and Goldmann-correlated IOP (IOPg) were measured by ORA preoperatively and 1 week and 1 and 3 months postoperatively. Central corneal thickness (CCT) was measured using the ORA's integrated handheld ultrasonic pachymeter. RESULTS:The mean preoperative CCT (537 mu m +/- 46 [SD]) did not change significantly by the end of 1 month postoperatively. The mean preoperative IOPcc (17.2 +/- 3.0 mm Hg) decreased significantly by 3 months postoperatively (15.2 +/- 3.7 mm Hg) (P = .018). The mean CH decreased from 10.36 +/- 1.48 mm Hg preoperatively to 9.64 +/- 1.26 mm Hg at 1 week (P = .028); it increased to preoperative values at the end of 1 month (10.20 +/- 1.70) and 3 months (10.74 +/- 1.54) (P > .05). The mean CRF decreased from 10.94 +/- 2.54 mm Hg preoperatively to 9.99 +/- 1.77 at 1 week (P = .026); it increased to preoperative values at 1 month (10.26 +/- 1.59) and 3 months (10.35 +/- 1.46) (P > .05). CONCLUSIONS: Although CH and the CRF decreased in the early postoperative period, the parameters increased and reached preoperative values by 3 months postoperatively, showing that corneal biomechanical properties are influenced by phacoemulsification and IOL implantation.