Variance of intraocular pressure readings after laser in-suit keratomileusis

Objective To evaluate the variance of intraocular pressure readings after laser in suit keratomileusis (LASIK). Methods The intraocular pressure readings of 340 eyes were measured with noncontact tonometer(NCT) before and one year after LASIK.Results The IOP readings after LASIK were lower than those before LASIK ( t =56 118, P 0.001). The data were divided into four groups according to the diopter before LASIK: groupⅠ: -3.00~-6.00D; groupⅡ: -6.00~-9.00D; group Ⅲ:-9.00~-12.00D; group Ⅳ: more than -12.00D. The IOP readings after operation were lower than those before operation in each group ( t 15, P 0.001). The spherical equivalent was significantly correlated with the reduction in IOP readings ( r=0.164, P =0.002) and the partial correlative coefficient was 0.152( P =0.005) if the cylindrical equivalent was controled.Conclusion IOP readings after LASIK are lower than those before operations. The differences of IOP readings between before and after LASIK are increased with the increasment of the degree of laser treatment.