Laser in situ keratomileusis, or LASIK, was first described in 19901; since then, it has surpassed cataract surgery as the most common eye operation performed in the world.2 As many as 1.5 million corneal refractive laser surgeries are done annually in the United States.3,4

LASIK involves lifting a corneal flap with a microkeratome and ablating the corneal stromal tissue with an excimer laser to achieve refractive change.5 This procedure can correct myopia, astigmatism, and hyperopia with minimal discomfort. After surgery, visual recovery is rapid and refractive stability is good.3 Residual refractive error may be treated with repeated LASIK surgery.

According to recent guidelines from the American Society of Cataract and Refractive Surgery, LASIK is appropriate for patients with the following characteristics6:
  • Age older than 18 years.
  • Stable prescription for at least 2 years.
  • Cornea sufficiently thick to allow for corneal flap of appropriate depth.
  • Myopia, up to --12 diopters; astigmatism, up to 6 diopters; or hyperopia, up to +6 diopters.
  • No other eye diseases.
  • No disorders or medications that could impair healing.
  • Awareness of risks and benefits of surgery and realistic expectations.

The Table lists contraindications to LASIK surgery.6

  Table — Contraindications to LASIK
Relative contraindications  
 
  • Age younger than 18 y
  • Unstable vision (prescription has changed within past 2 y)
  • Ocular herpes within the last 12 mo
  • Dry eyes, which may worsen after surgery
  • Scarring of the cornea
  • Pregnancy
  • Breast-feeding
  • Autoimmune disease
  • Corticosteroid or immunosuppressant therapy
  
Contraindications
  • Severe refractive errors that fall outside the FDA-approved dioptric range for correction*
  • Corneal disease or corneal thinning disorder, such as keratoconus or pellucid marginal degeneration
  • Cataracts, advanced glaucoma, or certain other eye diseases that threaten vision
  
LASIK, laser in situ keratomileusis.
*FDA-approved dioptric range for correction with current LASIK technology: myopia, up to − 12 diopters; astigmatism, up to 6 diopters; hyperopia, up to + 6 diopters.3
Adapted from The Eye Surgery Education Council. LASIK Surgery Screening Guidelines for Patients. 2002.6

Fewer than 1% of patients who undergo the procedure have serious, vision-threatening complications.6 Less serious complications occur more frequently and delay full recovery. 2,7 These complications can result in glare and halos that occur in dim lighting and may be severe enough to interfere with normal activities, such as night driving. Most of these problems resolve several months after surgery.6