Abstract:AIM: To compare the characteristics of corneal wavefront aberrations following small incision lenticule extraction(SMILE)and Q-value-guided femtosecond laser-assisted in situ keratomileusis(Q-value-FS-LASIK), and to evaluate the impact of these two procedures on visual quality.
METHODS:A total of 60 myopic patients(120 eyes)who underwent refractive surgery between January 2024 and June 2024 were enrolled and divided into two groups: the SMILE group(60 eyes)and the Q-value-FS-LASIK group(60 eyes). Preoperatively and at 1, 3, and 6 mo postoperatively, the following parameters were measured using the Pentacam HR and iTrace systems within a 6 mm corneal zone: root mean square of higher-order aberrations(RMS HOA), spherical aberration, vertical coma, horizontal coma, trefoil, Strehl ratio(SR), and modulation transfer function(MTF). Patient-reported outcomes(PROs)were used to assess subjective visual quality, and group differences were compared.
RESULTS:The general data of the two groups were comparable. At 6 mo postoperatively, uncorrected visual acuity(UCVA)was ≥1.0 in both groups, and the spherical equivalent(SE)remained within ±0.50 D. The total RMS HOA was significantly lower in the SMILE group(0.38±0.12 μm)than in the Q-value-FS-LASIK group(0.45±0.15 μm; P=0.012). Spherical aberration was higher in the Q-value-FS-LASIK group(0.52±0.18 μm)compared to the SMILE group(0.35±0.14 μm; P<0.001), while vertical coma was significantly greater in the SMILE group(0.21±0.09 vs 0.12±0.07 μm; P=0.003). No significant intergroup differences were observed in horizontal coma or trefoil(all P>0.05). The SR was superior in the SMILE group(0.26±0.05)compared to the Q-value-FS-LASIK group(0.22±0.04; P=0.008). PROs indicated a lower incidence of nighttime driving difficulties in the SMILE group(12% vs 21%; P=0.023).
CONCLUSION:Q-value-FS-LASIK effectively controls spherical aberration by optimizing corneal asphericity but results in higher total higher-order aberrations. SMILE reduces total aberrations due to its flap-free design but induces greater vertical coma. The choice of procedure should be tailored to the patient's refractive status and visual demands.
