Table 2.

Baseline and postoperative 3mm and 6mm higher order aberrations in cases of moderate myopia treated with SMILE, femto-LASIK, and PRK

Index	Pupil diameter	Surgical method	Pre-operative	3 M follow-up	12 M follow-up	One-year change	P-value
Total coma (µm)	6-mm	SMILE	0.22 ± 0.21	0.36 ± 0.16	0.38 ± 0.18	0.16 ± 0.23a	0.012b 0.021c
		Femto-LASIK	0.21 ± 0.09	0.41 ± 0.23	0.46 ± 0.31	0.25 ± 0.23a
		PRK	0.24 ± 0.17	0.45 ± 0.18	0.48 ± 0.20	0.24 ± 0.24a
	3-mm	SMILE	0.11 ± 0.10	0.14 ± 0.08	0.15 ± 0.11	0.04 ± 0.12	0.313b 0.791c
		Femto-LASIK	0.17 ± 0.62	0.14 ± 0.11	0.16 ± 0.15	-0.01 ± 0.64
		PRK	0.11 ± 0.08	0.14 ± 0.09	0.14 ± 0.13	0.03 ± 0.11
Total SA (µm)	6-mm	SMILE	0.21 ± 0.04	0.30 ± 0.10	0.33 ± 0.12	0.11 ± 0.09a	< 0.001a < 0.001c
		Femto-LASIK	0.21 ± 0.05	0.42 ± 0.10	0.45 ± 0.10	0.24 ± 0.10a
		PRK	0.22 ± 0.07	0.43 ± 0.12	0.48 ± 0.11	0.26 ± 0.13a
	3-mm	SMILE	0.07 ± 0.03	0.07 ± 0.04	0.06 ± 0.03	-0.01 ± 0.04	0.125b 0.482c
		Femto-LASIK	0.06 ± 0.02	0.07 ± 0.03	0.07 ± 0.04	0.01 ± 0.03
		PRK	0.07 ± 0.03	0.07 ± 0.04	0.08 ± 0.03	0.01 ± 0.04
Total trefoil (µm)	6-mm	SMILE	0.14 ± 0.19	0.14 ± 0.07	0.13 ± 0.05	-0.01 ± 0.17	0.198b 0.271c
		Femto-LASIK	0.14 ± 0.06	0.18 ± 0.19	0.16 ± 0.15	0.02 ± 0.19
		PRK	0.14 ± 0.08	0.16 ± 0.08	0.15 ± 0.05	0.01 ± 0.11
	3-mm	SMILE	0.12 ± 0.09	0.16 ± 0.08	0.14 ± 0.08	0.02 ± 0.12	0.122b 0.342c
		Femto-LASIK	0.13 ± 0.09	0.14 ± 0.08	0.13 ± 0.12	0.00 ± 0.11
		PRK	0.12 ± 0.07	0.15 ± 0.08	0.14 ± 0.10	0.02 ± 0.11

^a Within subgroup statistically significant change

^b Comparison of one-year change in indices between SMILE and femto-LASIK

^c Comparison of one-year change in indices between SMILE and PRK

M months, SA spherical aberration, PRK photorefractive keratectomy, SMILE small incision lenticule extraction, femto-LASIK femtosecond-assisted laser in-situ keratomileusis