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(Laser-Assisted In Situ Keratomileusis)

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LASIK is a surgery that uses a laser to reshape the cornea of the eye. This reshaping changes focusing power and usually corrects vision. Surgery may be done on both eyes, either at the same time or on separate occasions.

Cornea of the Eye
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Reasons for Procedure

LASIK is done to reduce the need for glasses or contact lenses.

Most people who get LASIK will still need reading glasses at middle age and beyond to correct for presbyopia (decreased ability to focus due to age). Be sure to discuss presbyopia with your doctor prior to getting LASIK so that you understand how it will affect your vision.

Possible Complications

LASIK eye surgery has a relatively low complication rate, but they can occur. Possible complications include, but are not limited to:

  • Under- or over-correction of the cornea shape
  • Infection
  • Scarring
  • Fuzzy or blurry vision
  • Poor night vision
  • Seeing halos or sunbursts around light/glare
  • Long-term dryness, scratchiness, or pain in eyes
  • Correction may not last
  • Permanent decrease or loss of vision that cannot be corrected with glasses or contact lenses
  • Need for additional surgery

Some factors that may increase the risk of complications include:

  • Pre-existing eye disease, such as glaucoma, or abnormalities in the shape of the cornea, such as keratoconus
  • Persistent eye infections, such as blepharitis
  • Dry eyes
  • Thin cornea
  • Large pupil size
  • Autoimmune disease, immunodeficiency, and other conditions, or use of medications that alter wound healing
  • Diabetes
  • Any other form of fluctuating vision

What to Expect

Prior to Procedure

Your doctor will likely do the following:

  • Complete eye exam
  • Review of medications

Leading up to your procedure:

  • It is best to stop wearing your contact lenses at least 2-4 weeks before surgery. The length of time depends on the type of contact lenses and your doctor’s preference.
  • Arrange for a ride to and from the procedure.
  • Do not wear lotion, cream, make-up, or perfume the day before or day of surgery.
  • You may be asked to scrub your eyelashes and/or use eye drops before the surgery.

Talk to your doctor about your medications. You may be asked to stop taking some medications up to 1 week before the procedure.


Drops are given to numb the surface of the eye. You may be given a sedative to help you relax during the procedure.

Description of Procedure

You will be positioned on your back in a reclining chair. The eyelid will be held open with a special device. A ring will be placed on the eye and pressure is applied to create suction. A blade will then be attached to the suction ring. The blade will be used to cut a flap in the cornea. The flap will be folded back.

You will look into a light (not the laser). A laser will be directed to remove a specific amount of corneal tissue. The laser will make a ticking sound as it reshapes the cornea. At this point, some patients report a smell similar to burning hair. When the laser is finished, the corneal flap will be gently placed back into position. Antibiotic drops will be put in the eye. A shield will be placed over the eye.

There are other ways to do laser vision correction surgery. One includes using a laser to make the flap in the cornea. The other includes removing the top layer of the cornea with a special device or chemical, then using the laser. Ask your doctor which procedure is best for you.

How Long Will It Take?

Less than 30 minutes.

How Much Will It Hurt?

You will likely feel some discomfort when the suction ring is applied. Just after the procedure, expect a burning or itching sensation or the feeling that there is a foreign object in your eye. Your eye may tear and be red and bloodshot. You will most likely have a loss of vision at times during the procedure. This is normal.

Post-Procedure Care

At the Care Center

Right after the procedure, the staff may:

  • Give you pain medication
  • Instruct you to avoid rubbing your eyes.

During your stay, the hospital staff will take steps to reduce your chance of infection such as:

  • Washing their hands
  • Wearing gloves or masks

There are also steps you can take to reduce your chances of infection such as:

  • Washing your hands often and reminding visitors and healthcare providers to do the same
  • Reminding your healthcare providers to wear gloves or masks

At Home

When you return home, take these steps:

  • Limit physical activity, especially contact sports for up to 1 month.
  • Do not put a contact lens or anything else in the operative eye unless instructed by your doctor.
  • Do not swim in a pool, or use a whirlpool or hot tub for 1-2 months.
  • Do not use cream, lotion, or make-up near the eye for at least 2 weeks.
  • Follow your doctor's instructions.

Call Your Doctor

Contact your doctor if your recovery is not progressing as expected or you develop complications such as:

  • Redness, swelling, increasing pain, bleeding, or discharge from the eye
  • Signs of infection, including fever and chills
  • Vision worsens
  • Any other problems or concerns

If you think you have an emergency, call for emergency medical services right away.


American Optometric Association

Eye Smart—American Academy of Ophthalmology


Canadian Ophthalmological Society

Health Canada


Lasik-Laser eye surgery. Eye Smart—American Academy of Ophthalmology website. Available at: Accessed May 9, 2016.

Medical devices. United States Food and Drug Administration (FDA) website. Available at: Updated October 20, 2015. Accessed May 9, 2016.

Last reviewed May 2018 by Michael Woods, MD