Assessment of Corneal Biomechanical Properties Following SMILE and LASEK in Patients with Moderate to High Myopia and Thin Corneas: A Retrospective Comparative Analysis

By
Ran Zhang
Yunlong Zhong
Hongxi Wu
Yuantu You
Xiaohan Su
Yusheng Li
Xingtao Zhou
Nanye Wang
February 25, 2026
0 min

Bmc Ophthalmology

Overview

This study compares corneal biomechanical properties and refractive outcomes following SMILE and LASEK in patients with moderate to high myopia and thin corneas (CCT ≤ 530 μm). It highlights the importance of evaluating biomechanical stability to mitigate risks of complications such as keratectasia.

Background

Corneal refractive surgery is widely practiced but carries risks, particularly in patients with thin corneas, which are associated with complications like keratectasia. Understanding the biomechanical changes post-surgery is crucial for ensuring long-term stability and safety in these patients. This study addresses a gap in comparative data between SMILE and LASEK in patients with corneal thickness near critical thresholds.

Data Highlights

Group	Number of Eyes	Mean CCT (μm)
SMILE	24	Average CCT
LASEK	23	Average CCT

Key Findings

Both SMILE and LASEK were performed on patients with CCT ≤ 530 μm.
Biomechanical properties were assessed using the Corvis ST II metrics.
LASEK showed smaller long-term biomechanical changes compared to SMILE.
Significant changes in corneal biomechanics were observed within the first year post-surgery.
Long-term stability was evaluated at the 2-year mark, indicating a plateau in biomechanical changes.

Clinical Implications

Surgeons should consider the biomechanical properties of the cornea when selecting surgical techniques for patients with thin corneas. The findings suggest that LASEK may offer a more favorable biomechanical profile compared to SMILE in this patient population, potentially reducing the risk of complications.

Conclusion

This study underscores the importance of evaluating corneal biomechanical stability in patients undergoing refractive surgery, particularly in those with thin corneas. Further research is needed to refine surgical decision-making in this critical patient group.