Effects of corneal thickness and axial length on intraocular pressure and ocular pulse amplitude before and after cataract surgery

Abstract

Objective To investigate the relationship between the biophysical properties of the cornea and eye on the intraocular pressure (IOP) and ocular pulse amplitude (OPA) before and after cataract surgery. Design Intervention study. Participants The left eyes of 311 patients. Methods The left eyes of 338 patients undergoing cataract surgery without other eye pathology were studied. IOP and OPA were recorded by dynamic contour tonometry (DCT) 1 week before and 14 weeks after cataract surgery. The axial length, corneal curvature, central corneal thickness, anterior chamber depth, and anterior chamber angle were measured 1 week before cataract surgery. Multiple regression analyses of these factors to the preoperative OPA were performed. The difference between the pre- and postoperative IOP and OPA were investigated by paired t tests. Results Three hundred and eleven of 338 eyes were analyzed. The preoperative OPA was negatively correlated with axial length (β = −0.24, p < 0.0001) and positively correlated with the preoperative IOP (β = 0.13, p < 0.0001). The average OPA was significantly decreased after cataract surgery ( p < 0.0001). The mean change in postoperative OPA was −0.45 ± 0.63 mm Hg (95% CI −0.52 to −0.38 mm Hg). Conclusions The preoperative OPA was negatively correlated with axial length as reported. A significant decrease in OPA was observed after the cataract surgery.