Wavefront aberration and its association with central corneal thickness and ablation depth in myopic eyes after LASIK surgery

Abstract

Objective To investigate the association between postoperative center corneal thickness (CCT), ablation depth and wavefront aberrations in the anterior corneal surface and the whole eye in myopic eyes after laser in situ keratomileusis (LASIK) surgery. Methods Retrospective study. One hundred and eight-four subjects (349 eyes) were enrolled in this study. The wavefront aberrations in the anterior corneal surface and the whole eye were measured using the Humphrey corneal topography and the WASCA wavefront analyzer at more than 3 months after LASIK surgery.The center corneal thickness was measured with a pachymeter. All statistical correlation analyses were performed using SPSS 15.0 software. Results The results about the association between CCT, ablation depth and wavefront aberrations after surgery would be: ①In the anterior corneal surface,Z4, Z5, Z7, Z8, Z12, Z24 in right eye and Z4, Z12 in left eye had statistically significant correlation with CCT. Z3, Z4, Z5, Z7, Z8, Z11, Z12, Z16, Z18, Z19, Z24 in right eye and Z4,Z7, Z9, Z10, Z11, Z12, Z14, Z23, Z24 in left eye had statistically significant correlations with ablation depth. ②In the whole eye, Z7, Z8, Z16 in right eye and Z3, Z5, Z8, Z10, Z12 in left eye had statistically significant correlations with CCT. Z5, Z6, Z7, Z8, Z24 in right eye and Z5,Z10, Z11, Z12, Z13, Z20, Z24 in left eye had statistically significant correlation with ablation depth. ③Corneal HOA RMS, whole eye HOA RMS, corneal total RMS, whole total RMS had statistically significant negative correlations with CCT, and had statistically positive correlations with ablation depth. Conclusion ①After LASIK surgery, the correlation of whole eye and anterior corneal surface aberrations are strongly manifested on defocus aberration, spherical aberration etc., they are all on-axis aberrations and significantly affected by CCT and ablation depth. ②Postoperative CCT and ablation depth are important factors for whole eye and anterior corneal surface aberrations after LASIK surgery, especially for corneal HOA RMS. Key words: Wavefront aberrations, whole eye; Wavefront aberrations, anterior corneal; Ablation depth; Corneal thickness,central; Keratomileusis,laser in situ