Overview
Laser eye surgery is a medical procedure designed to correct refractive vision errors such as nearsightedness, farsightedness, and astigmatism. The goal is to reduce or eliminate the need for glasses or contact lenses by reshaping the cornea so that light focuses correctly on the retina.
Modern laser eye treatments have been performed worldwide for more than 30 years and are considered safe and effective when patients are properly selected.
Which vision problems can be treated?
- Nearsightedness (myopia): objects far away appear blurry
- Farsightedness (hyperopia): nearby objects appear blurry
- Astigmatism: distorted or blurred vision due to irregular cornea shape
- Presbyopia: age-related difficulty focusing on close objects (reading vision)
The exact correction range depends on corneal thickness, curvature, and overall eye health.
How laser eye surgery works
The cornea consists of several layers. Laser eye surgery reshapes the stromal layer, which is the thickest and strongest part of the cornea. Once reshaped, the cornea permanently changes how light enters the eye, improving vision.
The treated cornea maintains its new shape for life.
Main laser eye surgery techniques
PRK / LASEK
PRK (Photorefractive Keratectomy) and LASEK are surface-based treatments where the outer layer of the cornea is removed or lifted before reshaping the underlying tissue with an excimer laser.
- Oldest laser technique with long-term clinical history
- No corneal flap is created
- Laser correction takes less than 1 minute
- Full procedure takes about 5 minutes
- Temporary discomfort and light sensitivity possible during first days
- Vision stabilizes over several weeks to months
Femto-LASIK
Femto-LASIK uses two lasers: a femtosecond laser to create a thin corneal flap, and an excimer laser to reshape the cornea underneath.
- Very fast visual recovery (often within 24 hours)
- Minimal discomfort after surgery
- Stable vision usually achieved within 6 weeks
- Flap is repositioned after correction
ReLEx SMILE
ReLEx SMILE is a minimally invasive technique using only a femtosecond laser. A small internal disc of tissue (lenticule) is created and removed through a tiny incision.
- No corneal flap required
- Small incision (about 2 mm)
- Lower risk of dry eyes
- Fast recovery
- High precision for moderate to high myopia
- Very low retreatment rate (around 1%)
General comparison of techniques
- All procedures are fast (5–10 minutes)
- All are painless due to anesthetic eye drops
- PRK/LASEK recovery: about 7 days functional vision, full stabilization in 3 months
- Femto-LASIK recovery: about 24 hours functional vision, stabilization in 6 weeks
- ReLEx SMILE recovery: about 24 hours functional vision, stabilization in 6 weeks
- Dry eye risk: highest with LASIK, lowest with SMILE
Who qualifies for laser eye surgery?
- Age 18 or older
- Stable prescription for at least 1 year (preferably 3 years)
- Sufficient corneal thickness
- Regular corneal shape
- No serious eye diseases (glaucoma, retinal disease, herpes)
- No uncontrolled autoimmune diseases or uncontrolled diabetes
Preliminary eye examination
A full eye examination is required before deciding on treatment. This includes measuring corneal thickness, curvature, eye pressure, and retinal health.
- Stop wearing soft contact lenses 2 weeks before the exam
- Stop wearing hard contact lenses 4 weeks before the exam
- Vision may be blurry after the exam due to dilation drops
- Results are usually valid for 3 months
Important medical disclaimer
This information is provided for educational purposes only. Laser eye surgery suitability, technique choice, and outcomes depend on individual medical evaluation by a licensed ophthalmologist.