Megan Freedman

What is LASIK?

LASIK stands for laser-assisted in situ keratomileusis. It is a minor but technical surgical procedure used to correct certain types of blurry vision (called refractive errors), including farsightedness, nearsightedness, and astigmatism. To perform LASIK, doctors use a laser to remove very thin layers of the cornea to change its shape and produce clearer vision.

Light passes through the cornea (the clear layer that covers the iris) and the pupil before it is projected onto the retina in the back of the eye. Refractive errors are caused by light focusing in front of (hyperopia, or farsightedness) or behind (myopia, or nearsightedness) the retina. In astigmatism, the cornea has a slight “football” shape instead of a spherical shape. In addition, certain other types of blurry vision are caused by a misshapen cornea. LASIK changes the shape of the cornea, allowing it to more effectively focus light rays onto the retina.

LASIK is a common surgery with potential risks and complications, such as reduced vision, blurry vision, and halos. Less invasive treatment options, such as contact lenses and glasses, are available to you. Consider getting a second opinion about your treatment options before having LASIK.

Types of LASIK

The types of LASIK include:

  • Conventional LASIK is the most typical type of LASIK. A mechanical blade called a microkeratome is used to make the initial cut in the cornea, creating a flap. Then a laser precisely reshapes the corneal tissue under the flap.

  • All-laser (or bladeless) LASIK is performed with a laser keratome, which is a special type of laser to create the corneal flap, instead of a microkeratome.

  • Wavefront LASIK employs a newer type of laser to correct farsightedness and nearsightedness as well as more subtle corneal distortion.

Why is LASIK performed?

LASIK is a surgery that may be recommended to treat a variety of refractive vision errors. LASIK may be recommended for certain types of blurry vision (called refractive errors) including:

  • Astigmatism is the distortion of details in both close and distant vision because light rays do not focus clearly at one point on the retina due to the unequal curvature of the surface of the eye.

  • Hyperopia, or farsightedness

  • Myopia, or nearsightedness

Ask your doctor whether to have one or both eyes corrected at the same time.

LASIK is not an option for everyone with a refractive error. For example, LASIK may not be performed if your vision has changed within the past year or if you have certain medical conditions, such as poor wound healing, diabetes, lupus, glaucoma, herpes infections of the eye, or cataracts.

Ask your doctor about all of your treatment options. Consider getting a second opinion, especially if you are uncomfortable with having elective surgery that is not medically necessary. In addition to glasses and contacts, there are other surgical options available that may be more suited for your particular case.

Who performs LASIK?

An ophthalmologist will perform your LASIK procedure in an outpatient surgery clinic. An ophthalmologist is a doctor with specialized training in diseases, conditions and surgery of the eye.

How is LASIK performed?

LASIK is performed in an outpatient surgery clinic and takes about 30 minutes. It generally includes these steps:

  1. You lie on a table positioned under a large laser machine.

  2. Your team numbs your eye with a liquid topical anesthetic. Your doctor may also give you a mild oral sedative prior to the procedure to make you feel relaxed. You can also request a sedative.

  3. Your doctor inserts a speculum between your eyelids to keep your eye open. Your doctor places a suction ring on your eye to hold the cornea in place for the procedure. The suction ring usually feels like a finger pressing on your eyelid and it will cause your vision to appear dim or completely black.

  4. Once preparations are complete, the doctor cuts a small, thin flap in your cornea using either a laser or a mechanical blade called a microkeratome.

  5. The doctor folds back the corneal flap and uses a laser to remove very thin layers of corneal tissue, which reshapes the cornea. You will probably hear clicking sounds from the laser machine.

  6. The doctor replaces the corneal flap to its original position and smoothes its edges down, where it will heal without stitches.

  7. If you are having both eyes operated on in the same visit, the procedure will be repeated on the other eye.

Will I feel pain?

Your comfort and relaxation are important to both you and your care team. Your surgeon will numb your eyes with anesthetic drops. You might get a mild sedative, such as diazepam (Valium), to help you relax. It is common to be startled when the suction ring is placed on your eye. You may feel pressure on your eye during the procedure but it is not painful. Your care team will take care of any pain or discomfort. Tell a member of your care team if you are uncomfortable in any way.

What are the risks and potential complications of LASIK?

Complications during and after LASIK are not common, but surgery involves risks and the possibility of complications, which may become serious in some cases. A potentially serious complication is a problem with the device that cuts the cornea to produce a flap. Although very rare, it is possible to accidentally cut through the cornea instead of making a hinged flap. This may lead to permanent damage to the eye.

Other potential complications include:

  • Bulge in the cornea
  • Corneal scarring
  • Dry eye syndrome
  • Infection of the cornea
  • Over-correction or under-correction of your vision 
  • Permanent vision loss or reduced vision
  • Visual distortions such as halos, glare, or double vision

Reducing your risk of complications

You can reduce the risk of certain complications by following your treatment plan and:

  • Following activity, dietary and lifestyle restrictions and recommendations before surgery and during recovery. This may include not swimming and doing certain other water or sports-related activities for up to several weeks.

  • Keeping all scheduled postoperative appointments

  • Notifying your doctor immediately of any concerns, such as severe eye pain or worsening vision 

  • Refraining from rubbing or itching your eyes after surgery as directed, as this may disturb the healing corneal flap

  • Taking your oral and topical medications exactly as directed

  • Telling all members of your care team if you have any allergies

How do I prepare for LASIK?

You are an important member of your own healthcare team. The steps you take before surgery can significantly improve your outcome after the procedure. You can prepare for LASIK by:

  • Answering all questions about your medical history and medications you take. This includes prescriptions, over-the-counter drugs, herbal treatments, and vitamins. It is a good idea to carry a current list of your medical conditions, medications, and allergies at all times.

  • Arranging for someone to drive you home after the surgery

  • Getting preoperative testing as directed. Preoperative testing will include a thorough eye exam and other tests as needed. Discontinue contact lens wear before the preoperative exam.

  • Not wearing contact lenses, eye makeup, and face lotions on the day of surgery

  • Taking or stopping medications exactly as directed

Questions to ask your doctor

Facing surgery can be stressful. It is common for patients to forget some of their questions during a doctor’s office visit. You may also think of other questions after your appointment. Contact your doctor with concerns or questions before surgery and between appointments.

It is also a good idea to bring a list of questions to your preoperative appointment. Questions can include:

  • Why am I a good candidate for LASIK?

  • Why d