Refractive Surgery: LASIK

LASIK (pronounced "LAY-sik") stands for laser in-situ keratomileusis. It's a technique for reshaping your cornea. It can help you see better without glasses or corrective lenses. This procedure uses an excimer laser, which makes a concentrated beam of cool ultraviolet (UV) light. Each pulse of the laser can remove a tiny portion of corneal tissue. LASIK can be used to correct farsightedness (hyperopia) and nearsightedness (myopia). It can also correct vision problems caused by irregularities in the cornea (astigmatism).

Eye showing cornea and flap

Eye showing laser beam

Eye showing a reshaped cornea and replaced flap

What to expect during the procedure

  • Before treatment, you may be given medicine to help you relax.

  • Eye drops numb your eyes. A device is used to keep your eyes open.

  • You may feel light pressure, but no pain, as your surgeon makes the flap in the top layer of the cornea (epithelium). The flap is folded back, but stays attached to the cornea.

  • Your surgeon uses a computer-guided excimer laser to reshape the cornea. Laser treatment lasts for 10–90  seconds.

  • The flap is put back into place. The corneal tissue sticks to itself while it heals.

  • After treatment, your vision will start to get better right away. It should become stable in 1–3 months.

Pros of LASIK

  • Little, if any, pain after surgery

  • Fast recovery

  • Very accurate, even for severe refractive problems

  • Serious haze after surgery unlikely

  • Structure of cornea stays intact

Cons of LASIK

  • Risk of flap complications, infection, or inflammation

  • Risk of blurred or distorted vision

  • Possible temporary or permanent dry eye

  • Risk of night vision problems, such as halos, glare, or starbursts

  • Possible undercorrection or overcorrection

  • Possible loss of best corrected vision