Analysis of changes in crystalline lens thickness and its refractive power after laser in situ keratomileusis

AIM:To evaluate changes in the anterior chamber depth (ACD),crystalline lens thickness (LT) and its refractive power after laser in situ keratomileusis (LASIK).· METHODS:In all cases,the preoperative and postoperative central ACD which were measured with Pentacam,Orbscan,IOL-Master and A-scan ultrasonography,central corneal true net power which was measured with the Pentacam,Orbscan and IOL-Master,axial length (AL) which was measured with IOL-Master and LT which was measured with the A-scan ultrasonography were compared using the paired sample t test.Ocular refractive errors and lens refractive power at corneal plane were calculated and their correlations were also evaluated before and after LASIK. RESULTS:At 1 week after LASIK,LT and crystalline lens refractive power at corneal plane (Dlens) which were associated with the IOL-Master and Pentacam increased significantly (P ≤0.005),ACD decreased significantly(P ≤0.001),but no significant increase was observed in the Dlens which was associated with the Orbscan(P =0.261).Significant correlations between the changes in the ocular refractive errors and Dlens which were associated with the Pentacam were observed at 1 week and 6 months after LASIK (P=0.028;P =0.001).CONCLUSION:LT increased significantly after LASIK,and this might partially lead to ACD decrease,Dlens increase and a small quantity of myopic regression.