A Randomized Controlled Trial Comparing Clinical Effectiveness of SMILE Versus SMILE Xtra in Myopia

A Randomized Controlled Trial Comparing Clinical Effectiveness of SMILE Versus SMILE Xtra in Myopia

To evaluate and compare the clinical efficacy, biomechanical stability, and optical quality of SMILE and SMILE Xtra procedures in patients with myopia through a randomized controlled trial

Inclusion Criteria:

1. Age 18-50 years
2. MRSE (Manifest Refraction Spherical Equivalent) -6.00D to -10.00D with refractive changes within ±0.50D in past 2 years
3. CDVA (Corrected Distance Visual Acuity) ≥ 20/25
4. Myopia progression ≤ 0.50D/year for ≥2 years
5. RST (Residual Stromal Thickness) ≥ 250μm after lenticule removal
6. Contact lens discontinuation as per protocol

Exclusion Criteria:

1. Other eye diseases (keratoconus, glaucoma, etc.)
2. Corneal scarring, cataracts affecting observation
3. Systemic diseases affecting surgery compliance
4. Prior ocular surgeries
5. Pregnancy, breastfeeding, or menstruation
6. Drug allergies to surgical medication