Table 1.

Topography-derived corneal wavefront errors after LASIK (4 mm diameter pupil).

	Wavefront Error (Root Mean Square, µm)						Mean MDD between treatments (µm)
	Before LASIK	1 month	3 months	6 months	12 months	36 months
All High Order Aberrations
Bladeless	0.14 ± 0.07	0.19 ± 0.05a	0.18 ± 0.05	0.17 ± 0.04	0.19 ± 0.07	0.18 ± 0.04	0.05
Microkeratome	0.14 ± 0.04	0.16 ± 0.04b	0.17 ± 0.05c	0.16 ± 0.05d	0.19 ± 0.08b	0.18 ± 0.05b
Spherical
Bladeless	0.04 ± 0.02	0.07 ± 0.04	0.07 ± 0.03c	0.06 ± 0.03	0.06 ± 0.03	0.07 ± 0.03b	0.03
Microkeratome	0.04 ± 0.02	0.06 ± 0.03	0.06 ± 0.03	0.06 ± 0.03	0.06 ± 0.04	0.06 ± 0.03
Coma
Bladeless	0.07 ± 0.06	0.11 ± 0.06	0.10 ± 0.06	0.10 ± 0.06	0.12 ± 0.06	0.10 ± 0.06	0.05
Microkeratome	0.07 ± 0.03	0.08 ± 0.04	0.09 ± 0.05d	0.09 ± 0.04c	0.11 ± 0.07b	0.09 ± 0.04d
Trefoil
Bladeless	0.06 ± 0.05	0.07 ± 0.04	0.06 ± 0.03	0.06 ± 0.04	0.06 ± 0.05	0.07 ± 0.04	0.04
Microkeratome	0.06 ± 0.03	0.08 ± 0.04	0.07 ± 0.04	0.06 ± 0.03	0.08 ± 0.04	0.07 ± 0.04

Data are presented as mean ± standard deviation; n=21.

There were no differences between femtosecond laser (bladeless) and microkeratome treatments at any time; the mean minimum detectable difference (mean MDD) between treatments is indicated (α=0.05/6, β=0.20, n=21, paired analysis).

^ap=0.04,

^bp<0.01,

^cp=0.01,

^dp=0.02,

^ep=0.03,

^fp=0.05, versus preoperative; P-values were adjusted for 5 comparisons by using the Bonferroni technique.