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

Abstract

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.

Keywords: anterior chamber depth; crystalline lens thickness; refractive power.