SMILE Demonstrates Greater Corneal Tissue Preservation, Biomechanical Stability vs. LASIK

Findings from a recent study presented at ARVO 2026 in Denver suggest that procedure selection (SMILE vs. LASIK) may be more influential on postoperative corneal biomechanics than the addition of prophylactic cross-linking. Photo: Bobby Saenz, OD. Click image to enlarge. Some cornea specialists advise combining a refractive surgery such as LASIK or SMILE with corneal crosslinking (CXL) to help protect a borderline cornea from weakening after surgery. A recent study presented at ARVO 2026 in Denver found little merit to that, however.  A team from Philadelphia reviewed published research to compare how much corneal tissue is removed and how much the cornea’s strength changes after these four procedures: LASIK, LASIK-Xtra (which added CXL), SMILE and SMILE-Xtra (also with CXL). It showed that SMILE procedures remove less corneal tissue and cause less weakening of the cornea compared to LASIK procedures, but adding CXL did not make a significant difference in tissue preservation or corneal strength.Seven studies (one RCT, six non-RCTs) from PubMed, Scopus and Embase reporting preoperative and postoperative central corneal thickness (CCT; 467 eyes) and/or corneal resistance factor (CRF; 290 eyes) measurements in patients undergoing LASIK, LASIK-Xtra, SMILE, or SMILE-Xtra with minimum three-month follow-up were included.SMILE-based procedures demonstrated greater corneal tissue preservation and biomechanical stability compared to LASIK-based procedures, and the addition of prophylactic CXL did not significantly alter CCT or CRF outcomes within either procedure type. These findings suggest that procedure selection (SMILE vs. LASIK) may be more influential on postoperative corneal biomechanics than the addition of prophylactic CXL. Exact findings are below:Mean CCT reduction was greatest for LASIK (103.9 ±23.8μm), followed by LASIK-Xtra (100.2 ±26.8μm), SMILE (87.5 ±33.6μm) and SMILE-Xtra (78.0 ±25.9μm). Mean CRF reduction followed a similar pattern: LASIK (4.95 ±1.42mmHg), LASIK-Xtra (4.25 ±1.71mm Hg), SMILE (2.83 ± 1.57mm Hg) and SMILE-Xtra (2.34 ±1.39mm Hg).Within-procedure comparisons showed no statistically significant differences in CCT between LASIK and LASIK-Xtra (MD: 3.7μm) or between SMILE and SMILE-Xtra (MD: 9.2μm). Across-procedure comparisons demonstrated significantly greater CCT reduction with LASIK compared to SMILE (MD: 16.7μm) and SMILE-Xtra (MD: 25.9μm). CRF comparisons showed LASIK produced significantly greater reduction than SMILE-Xtra (MD: 2.62mm Hg).In conclusion, this study suggests that choosing SMILE over LASIK may be more important for preserving corneal structure than adding crosslinking to either procedure. “These findings may help surgeons and patients make more informed decisions, particularly for individuals with thinner corneas or other risk factors where preserving corneal strength is especially important,” the study authors concluded in their ARVO abstract.Original abstract ©2026 Association for Research in Vision and Ophthalmology.Click here for the source. Fink J, Young A, Nguyen W, Shah C. Corneal biomechanical outcomes following LASIK, SMILE and prophylactic cross-linking: a systematic review and meta-analysis. ARVO annual meeting. This article was developed by the editorial staff in conjunction with experts in the field. In the process, AI may have been among the editorial tools used to meet the goals of human editors, who approved all content.