LASIK Eye Surgery: Overview

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Laser-assisted in situ keratomileusis (LASIK) surgery involves using a precisely targeted laser to reshape the cornea, the front part of the eye. In doing so, refractive errors like nearsightedness and farsightedness—issues with the way light rays bend in the eye—can be corrected and vision often permanently improved. While generally considered safe and effective, there are risks and recovery considerations to weigh. In addition, not everyone who might want LASIK is a suitable candidate.

Preparing patient for laser eye surgery
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What Is LASIK Eye Surgery?

LASIK is an elective surgery performed by an ophthalmologist (an eye surgeon) on adults, either in the healthcare provider's office or in an outpatient eye surgical center.

There are three main parts to LASIK eye surgery:

  • Corneal flap creating: A flap of corneal tissue is cut with a laser or mechanical blade and gently lifted. This "hinge" tissue keeps the flap attached to the eye so that it may be gently reapplied later.
  • Corneal reshaping: An excimer laser—a type of laser that emits ultraviolet light at a specific wavelength—is then used to reshape your cornea, so that light rays focus perfectly on your retina without the need for corrective lenses.
  • Corneal repositioning: Finally, the corneal flap is placed carefully back onto your cornea and smoothed out.

Various Surgical Techniques

There are two main surgical techniques that eye surgeons use to perform LASIK:

  • Traditional LASIK: This technique uses your refractive error measurement (what is used to determine the prescription of your glasses or contact lenses) to program the laser as it reshapes your cornea during surgery.
  • Custom LASIK: This technique utilizes a 3D-mapping system of a person's eye to guide the laser during surgery. The system, called wavefront-guided technology, provides information about the precise shape of the patient's cornea, as well as their unique eye distortions and irregularities.

While custom LASIK is generally a bit more expensive, it may potentially improve a patient's chances of achieving 20/20 vision or better after surgery. It may also reduce the chances of undesirable side effects from LASIK, such as seeing glares or halos or experiencing night vision disturbances.

Purpose of LASIK Eye Surgery

LASIK reshapes the cornea so that light can bend (refract) properly and be focused on the retina, where it's converted into nerve signals that are sent to your brain and interpreted as visual images.

LASIK eye surgery is performed to treat the following refractive error eye conditions:

The goal of LASIK is to permanently improve your vision. In most cases, LASIK eliminates the need to wear eyeglasses or contact lenses. That said, post-surgery vision may not be sharp forever.

Who Qualifies?

In order to undergo this surgery, a patient must meet the following criteria:

  • Be at least 18 years old
  • Have farsightedness, nearsightedness, or astigmatism that is not too severe and is stable (i.e., has not changed within the last year)

Optical abnormalities and conditions—for example, cone-shaped cornea (keratoconus), dry eye, and advanced or uncontrolled glaucoma)—and certain health conditions, like uncontrolled diabetes, rule you out as a candidate for this procedure.

Other conditions may be possible contraindications. Examples include certain autoimmune diseases (e.g., Sjögren's syndrome) or a history of abnormal wound healing.

Several unique and sophisticated eye tests will be performed to ensure you are a good candidate for LASIK surgery.

How to Prepare

Once your ophthalmologist has determined that you are a good candidate for LASIK, be sure to have an in-depth conversation with them about potential side effects and complications as well as what you should expect after the surgery.

Then, if you're ready to proceed, you can schedule your appointment and begin to prepare.

Preparing for your LASIK eye surgery entails logistics like knowing when you need to arrive and what to bring with you, as well as arranging to have someone drive you home (and help you) after the surgery.

It also involves steps to ensure that your surgery is as safe as possible, including preparing your eyes by avoiding wearing contacts and makeup and knowing what medications need to be stopped (and when) prior to your procedure.

Follow your healthcare provider's instructions specifically. If you're unsure about anything, ask.

What to Expect on the Day of Surgery

On the day of your surgery, you will arrive and wait to be called into the surgical room. You will likely fill out some forms, including one that consents to the surgery.

Upon entering the surgical room and sitting in a reclining chair, you may be given an anti-anxiety medication, such as Valium (diazepam), to help you relax and calm your nerves.

Next, the following steps will be performed by your surgeon or their assistant:

  • A sterile drape will be applied over the eye area to ensure a bacteria-free work area.
  • Several numbing eye drops will be placed into your eye.
  • After your eye is numb, you will be moved to the excimer laser, which performs the surgery.
  • When you are comfortable, a special tool will be used to hold your eye open and prevent it from blinking. Sometimes, a suction ring is also applied over the front of your eye to prevent eye movement.
  • Your cornea will then be marked with special surgical ink to start the process of creating a corneal flap.

Several safety measures will be taken during the procedure. Your surgeon has complete control and can turn the laser off at any time. If you move too much, the laser will automatically shut off.

The whole procedure usually takes less than 10 minutes per eye; your surgeon will only be operating on one eye at a time. You will, however, be in the office or surgical center for approximately 90 minutes.


During the first 24 hours after LASIK eye surgery, your surgeon will ask you to rest and relax your eyes.

At this time, you may experience symptoms such as eye discomfort, eye dryness, blurry vision, and light sensitivity. Some of these may ease within a day, while others may take up to a week or several weeks or months.

Within one to three days after surgery, most patients can return to their daily routine, including returning to work.

For the next two to four weeks, however, you will be advised to wear sunglasses during the day, wear a patch or eye shield at night, and avoid touching or applying anything around your eyes.

Your surgeon will also advise you to avoid certain activities for specific periods of time (one to multiple weeks), such as exercising and driving.

Long-Term Care

Most people are very satisfied with the outcome of their LASIK surgery, and the results can be dramatic.

Research shows that 99% of patients achieve at least 20/40 vision after LASIK, and more than 90% achieve 20/20 vision or better.

That said, while LASIK eye surgery provides a permanent improvement in your vision, your eyes will naturally change as you age (called presbyopia).

Therefore, your ophthalmologist will want to continue evaluating your eye health with regularly scheduled appointments long after the six-month recovery period.

Potential Risks

In addition to the symptoms that may be experienced during the recovery period, potential, though rare, risks and complications associated with LASIK eye surgery include:

  • Eye dryness, which can occur after surgery and sometimes persist for weeks to months
  • Eye infection (infectious keratitis)
  • An inflammatory eye condition called diffuse lamellar keratitis
  • Corneal flap problems (e.g., irregular or poor healing)
  • Refractive complications such as irregular astigmatism, worsening vision, or, more rarely, loss of vision (blindness)

Seek Immediate Medical Attention

While you may experience some mild eye discomfort after LASIK surgery, it's important to contact your healthcare provider right away if you experience any severe eye pain. Also contact your healthcare provider if you experience any unusual or worsening visual symptoms or get hit in the eye.

A Word From Verywell

While the actual LASIK surgery takes minutes to complete, the preparation and recovery process require time and patience. You will need to be diligent in following your surgeon's instructions and attending all of your follow-up appointments.

10 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  3. NVision Centers. Custom LASIK: Advantages and Disadvantages.

  4. Standford Health Care. Wave-front LASIK (Custom LASIK).

  5. American Refractive Surgery Council. (July 2017). Your LASIK Consultation: A Deeper Look Into What To Expect

  6. Flaum Eye Institute. LASIK and Advanced Vision Correction: Frequently Asked Questions.

  7. American Refractory Surgery Council. (May 2016). Beyond Seeing Clearly: What to Expect with LASIK recovery.

  8. Sandoval HP et al. Modern Laser in Situ Keratomileusis Outcomes. J Cataract Refract Surg. 2016 Aug;42(8):1224-34. doi:10.1016/j.jcrs.2016.07.012

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Additional Reading

By Troy Bedinghaus, OD
Troy L. Bedinghaus, OD, board-certified optometric physician, owns Lakewood Family Eye Care in Florida. He is an active member of the American Optometric Association.