LASIK, PRK, and SMILE are the most common types of laser eye surgeries, each with unique principles, benefits, and considerations.
Laser eye surgery—with the most prominent types including LASIK, PRK, and SMILE—has improved vision correction, providing millions of people with freedom from glasses and contact lenses.
Each procedure has its unique principles, benefits, risks, and ideal candidates. Understanding these differences can help patients make informed decisions about their eye care.
Understanding LASIK, PRK, and SMILE
LASIK (Laser-Assisted In Situ Keratomileusis)
LASIK involves creating a thin flap on the cornea using a microkeratome or femtosecond laser. The underlying corneal tissue is then reshaped with an excimer laser to correct refractive errors like myopia, hyperopia, and astigmatism. The flap is repositioned, allowing for quick recovery and minimal discomfort.
PRK (Photorefractive Keratectomy)
PRK removes the corneal epithelium entirely before reshaping the underlying tissue with an excimer laser. Unlike LASIK, PRK does not involve creating a corneal flap. The epithelium regenerates over a few days, which can result in a longer and slightly more uncomfortable recovery period compared to LASIK.
SMILE (Small Incision Lenticule Extraction)
SMILE is a minimally invasive procedure that uses a femtosecond laser to create a small, lens-shaped piece of tissue (lenticule) within the cornea. This lenticule is removed through a small incision, reshaping the cornea and correcting refractive errors. SMILE is particularly effective for myopia and astigmatism.
Pros and Cons

LASIK
Pros:
- Quick recovery, often within 24-48 hours.
- Minimal discomfort post-surgery.
- Suitable for a wide range of refractive errors.
Cons:
- Risk of flap complications.
- Dry eyes and glare are common side effects.
- Not ideal for patients with thin corneas or severe dry eyes.
PRK
Pros:
- No risk of flap complications.
- Suitable for patients with thin corneas.
- Lower risk of dry eye compared to LASIK.
Cons:
- Longer recovery period (up to a week or more).
- More discomfort during the initial healing phase.
- Temporary vision haze during the healing process.
SMILE
Pros:
- Minimally invasive with a small incision.
- Less impact on corneal nerves, reducing dry eye risk.
- Stable and predictable outcomes for myopia and astigmatism.
Cons:
- Limited to correcting myopia and astigmatism (not hyperopia).
- Newer procedure with fewer long-term studies.
- Longer visual recovery compared to LASIK.
Ideal Candidates
LASIK
Ideal for individuals with moderate to high myopia, hyperopia, or astigmatism and who have sufficient corneal thickness.
PRK
Suitable for patients with thin corneas, those engaged in contact sports, or those at risk of eye trauma, as it avoids flap-related complications.
SMILE
Best for patients with myopia and astigmatism seeking a minimally invasive option with a reduced risk of dry eyes.
Success Rates and Long-Term Outcomes

LASIK
- High success rates, with 96% of patients achieving 20/20 vision or better.
- Long-term stability, though some may require enhancements after several years.
PRK
- Comparable success rates to LASIK, with a slightly longer time to reach optimal vision.
- Fewer long-term complications, making it a viable option for certain patients.
SMILE
- Emerging data shows promising results, with success rates similar to LASIK.
- Stable vision correction and reduced incidence of dry eye.
Making the Right Choice
Choosing the right type of laser eye surgery depends on individual needs, eye anatomy, lifestyle, and personal preferences. Consultation with an experienced ophthalmologist is crucial in determining the most suitable procedure.
Each method—LASIK, PRK, and SMILE—offers unique benefits and considerations, ultimately providing paths to clearer vision and enhanced quality of life.
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