In SMILE (Small Incision Lenticule Extraction), a femtosecond laser creates intrastromal lenticules. Compared to LASIK, which biomechanical advantage does SMILE offer?

• A SMILE creates a larger flap hinge, distributing tension better
• B SMILE preserves more anterior stromal collagen fibres, maintaining greater corneal tensile strength ✓
• C SMILE uses excimer laser ablation, causing less corneal inflammation
• D SMILE corrects higher degrees of astigmatism than LASIK

Explanation

SMILE is flapless — the lenticule is removed through a small peripheral incision (~2-4 mm) without creating a flap, preserving anterior stromal collagen lamellae which are the strongest biomechanical component of the cornea. LASIK creates a full flap (120-150 μm) that severs Bowman's layer and anterior stroma circumferentially, reducing corneal rigidity. This biomechanical advantage makes SMILE particularly useful in patients with thin corneas or higher myopia.

Reference: Khurana Comprehensive Ophthalmology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.