Ten-Year Enhancement And Regression Rate After Small Incision Lenticule Extraction: Retrospective Review Of Over 110,000 Cases

To assess long-term enhancement rate after SMILE operation and to analyze the possible risk factors for post-op regression and re-operation.

Nunemiso Eye Clinic, Seoul, Republic of Korea.

Retrospective review of 110,971 cases of SMILE operation was done. UDVA, CDVA, SEQ, CCT was measured pre and post-operatively and surgical data was recorded. Overall and annual enhancement rates of total SMILE cases and the possible risk factors were analyzed. Also, regression and enhancement rates of SMILE, PRK and LASIK were compared in different myopic subgroups.

The overall enhancement rate of SMILE for more than 10 years was 0.33% (ranging 0.17%~2.02% annually). Preoperative SEQ, lenticule thickness, lenticule diameter, RSB and PTA were shown to have statistical correlation in enhancement after SMILE. In comparison with other refractive surgeries, SMILE showed the lowest regression rate(SMILE 1.7%, PRK 2.2% and LASIK 3.9%) and enhancement rate(SMILE 0.3%, PRK 0.7% and LASIK 1.0%) not just in overall but in all myopic range.

Long-term enhancement rate of SMILE is very low and post-op myopic regression occurred the least in SMILE regardless of the amount of the myopic error for correction. SMILE would be a safe refractive surgery with lower chance of retreatment.