Laser Eye Surgery (Refractive Surgery): Procedures, Benefits, Risks, and Candidacy

Laser refractive surgery reshapes the cornea to correct refractive errors (myopia, hyperopia, astigmatism, presbyopia). It's among the most studied elective procedures — with high satisfaction but important caveats.

Main Procedures

Procedure	Mechanism	Best For	Recovery	Key Pros/Cons
LASIK	Femtosecond laser flap + excimer ablation of stromal bed	Myopia -1 to -10D, hyperopia +1 to +4D, astig ≤4D	Vision: hours–days; full: 1–3 mo	Fast recovery, minimal pain; flap risks (dislocation, ectasia), dry eye
PRK / LASEK / Epi-LASIK	Surface ablation (no flap); epithelium removed/regenerates	Thin corneas, high risk of trauma, dry eye, military/police	Vision: days–weeks; full: 3–6 mo	No flap risk; more pain, slower visual recovery, haze risk (mitigated by MMC)
SMILE	Femtosecond lenticule extraction (small incision)	Myopia -1 to -10D, astig ≤3D	Vision: 1–2 days; full: 1–3 mo	Minimally invasive, less dry eye; no hyperopia; limited long-term data vs LASIK
Presbyopia-Correcting	Monovision LASIK, Presbyond, corneal inlays, RLE (lens replacement)	Age 40+ with presbyopia	Varies	Trade-offs: depth perception, night vision, may still need readers

Benefits

• Reduced/eliminated dependence on glasses/contacts
• Improved quality of life (sports, travel, convenience)
• Long-term cost savings vs. lifetime of corrective lenses
• Stable results: 95%+ maintain 20/20 or better at 10 years (LASIK/PRK)

Risks & Complications

• Dry Eye: 20–50% transient (3–6 mo); <5% chronic. Nerve disruption → reduced tear feedback.
• Visual Symptoms: Glare, halos, starbursts, ghosting — usually improve by 6 mo.
• Undercorrection/Overcorrection: 1–5%; enhancement possible after 3–6 mo.
• Ectasia: Corneal biomechanical failure (rare: 0.04–0.6%); screening (topography, biomechanics) critical.
• Infection (Infectious Keratitis): ~1/5000–10,000; sight-threatening.
• Flap Complications (LASIK): Dislocation, folds, DLK, epithelial ingrowth.

Candidacy Criteria

• Age ≥18 (ideally ≥21 for stability)
• Stable refraction ≤0.50 D change/year × 2 years
• Adequate corneal thickness (>500 µm for LASIK; >450 µm for PRK)
• Normal topography (no forme fruste keratoconus)
• Healthy ocular surface (controlled dry eye, no active inflammation)
• Realistic expectations
• Not pregnant/nursing
• No uncontrolled autoimmune/connective tissue disease

Pre-Op Evaluation

Comprehensive: Manifest + cycloplegic refraction, corneal topography/tomography (Pentacam), pachymetry, wavefront aberrometry, tear film analysis, dilated fundus exam.

Post-Op Care

• Antibiotic + steroid drops × 1–4 weeks
• Preservative-free artificial tears frequently (3–6 mo)
• Eye shield at night × 1 week (LASIK)
• No rubbing, swimming, eye makeup × 2–4 weeks
• Follow-up: 1 day, 1 week, 1 month, 3 months, 6 months, 1 year

Laser vision correction is life-changing for the right candidate. Choose a surgeon who screens rigorously, explains trade-offs honestly, and provides long-term follow-up.