Wavefront-guided LASIK outperforms SMILE for low to moderate myopia

This prospective, comparative study looked at visual, refractive, aberrometric and contrast sensitivity outcomes after small incision lenticule extraction (SMILE) and wavefront-guided LASIK (WFG LASIK).

Study design

A total of 110 eyes with low or moderate myopia (spherical equivalent ≤6.0 D) were enrolled, 51 of which underwent WFG LASIK and 59 of which underwent SMILE. Patients were followed for 6 months postoperatively.

Clinical outcomes

Compared with SMILE eyes, a higher proportion of WFG LASIK eyes achieved postoperative UDVA of 0.00 logMAR (90.2% vs 78.0%), spherical equivalent within 0.5 D (98% vs 81.5%) and cylinder of 0.5 D or less (100% vs 84.7%).

SMILE appeared to increase both higher order aberrations and root mean square (RMS) values, and decrease contrast sensitivity significantly more than WFG LASIK. Both patient groups had a significant correlation between attempted and achieved spherical equivalent correction; however, this correlation was stronger in WFG LASIK patients.

Loss of 1 line of DCVA occurred in 6.8% of WFG LASIK patients vs. 0% of SMILE patients.

Limitations

Preoperative visual acuity was better in the WFG LASIK group, which could have influenced the fnding of better visual acuity outcomes in this group. Also of note, one of the authors has a financial relationship with the company that owns one of the studied technologies.

Clinical significance

Despite the perceived conflict of interest, the study design is appropriate and the outcomes call into question the superiority of SMILE. Further evidence comparing its visual and biomechanical advantages against other refractive procedures is needed to support its adoption as the gold standard refractive treatment.