Analysis of visual quality of myopia and myopia combined with astigmatism after SMILE surgery for 1a

Abstract:

AIM: To present the visual quality and refractive outcomes obtained in small incision lenticule extraction(SMILE)refractive surgeries, and observe the follow-up of patients over 1a period.

METHODS: Retrospective comparative analysis of 85 patients(85 eyes)were treated with SMILE between July and December 2019. Pre- and postoperative uncorrected distance visual acuity(UDVA), corrected distance visual acuity(CDVA), spherical equivalent refraction(SE)were all observed, to evaluate the efficacy, safety and predictability after SMILE refractive surgery. Total corneal higher-order aberrations(HOAs), modulation transfer function cut-off(MTF_cutoff), strehl ratio(SR), and objective scattering index(OSI)were evaluated.

RESULTS: One year after SMILE refractive surgery, the efficacy index was 1.08, 84 eyes(99%)reached an UDVA as or over CDVA preoperatively, 22 eyes(26%)gained one line of CDVA than preoperatively. The safety index was 1.04, 59 eyes(69%)of the treated eyes had an unchanged CDVA postoperatively, 24 eyes(28%)gained one line of CDVA, 2 eyes(2%)gained two lines of CDVA. 85 eyes(100%)were all within ±0.50D. The pre-correction is highly related with the actual correction of SE(Y=0.9949X-0.0033; R²=0.9977). HOA, spherical aberration and coma were increased under pupil diameters of 6mm(all P<0.001). Both MTF_cutoff and SR were higher than that of SMILE preoperatively(P<0.05).

CONCLUSION: SMILE demonstrated to be safe, effective, and predictable in the treatment of myopia and myopic astigmatism, and good accuracy in correcting medium and low astigmatism. The post-quality of retinal image is better than that of SMILE preoperatively.