LASIK Eye Surgery: Purpose of LASIK


Laser Assisted In Situ Keratomileusis (LASIK) is a type of eye surgery performed to correct certain refractive errors which lead to general blurring or a hampered ability to see objects at different distances. LASIK reshapes the cornea to permanently improve your vision.


Diagnosis related to LASIK eye surgery

Your cornea is a transparent, domed fabric that covers the front of your eye. It is primarily responsible for the bending (“refraction”) of light rays as they enter the eye. This refraction allows light rays to focus precisely on your retina (located at the back of the eye), so you can see clearly and sharply.

A refractive error is caused by an abnormally shaped cornea, an eyeball that is too long or too short, or an aging lens.This results in the light rays not being properly focused on the retina, making your vision blurry.

The three main types of refractive errors corrected by LASIK are:

  • Myopia (myopia): when a person can only see near objects clearly (distant objects are blurred)
  • Presbyopia (hyperopia): when a person can only see distant objects clearly (near objects are blurred)
  • Astigmatism: When images are blurred, whether near or far

LASIK does not correct a type of refractive error called presbyopia. This eye condition causes farsightedness and results from the natural hardening of the lens with age.

LASIK is not considered medically necessary. Rather, it is an optional procedure for those who want an alternative to corrective eyewear.

While most people can give up their glasses and contact lenses after LASIK surgery, this may not be the case for the rest of their lives. This is because as people age, their eyes naturally change, making tasks like reading and seeing nearby objects more difficult.

Criteria and contraindications

Even if you have been diagnosed with nearsightedness, farsightedness, or astigmatism, you may not be a candidate for LASIK.

The basic criteria for undergoing LASIK surgery are:

  • You are at least 18 years old
  • Your refractive error should not be too large
  • Your refractive error must have been stable for more than a year (this means that your glasses or contact lens prescription has not changed significantly in the last year)

Absolute contraindications to LASIK surgery include the following conditions:

Use of certain medications, such as high doses of a steroid (eg, prednisone), or active participation in contact sports where you risk being hit in the eye (eg, boxing) , may also disqualify you as a LASIK candidate.

Other possible contraindications to LASIK surgery include:

  • A controlled autoimmune disease (for example, lupus Where rheumatoid arthritis)
  • History of abnormal wound healing
  • History of herpes keratitis
  • Diabetes (even controlled)
  • Glaucoma (even controlled)
  • History of refractive surgery

Although not an outright contraindication, people with larger pupils are also at greater risk of experiencing night vision problems, such as seeing glare or halos around eyes. lights, after LASIK eye surgery.

Tests and laboratories

During your two to three hour preoperative appointment, your eye doctor or optometrist will review your medical history and medication list. They will also perform several sophisticated tests that will give them the information they need regarding your overall eye health.

In addition to helping them determine if you are a good candidate for LASIK eye surgery, the information from the tests will help guide the surgeon once they have performed your procedure.

Stop wearing soft contact lenses for two to three weeks and rigid lenses for three to four weeks before your consultation. Contact lenses can temporarily change the shape of your cornea, which will affect your assessment.

Preoperative tests for LASIK generally include the following:

  • Refraction test: Measurements are taken to determine your prescription, and your eye doctor will dilate your pupils to make the test more accurate.
  • Dry eye test at assess the composition and volume of the tear film lining of the eye
  • Pachymetry measure corneal thickness
  • Wavefront analysis: This is used to more accurately understand distortions and irregularities of the eye, called higher order aberrations. This information can be useful during surgery, as it provides data about a patient’s unique visual system.
  • Corneal topography: A computer-aided tool creates a map of the shape of the cornea. This test can be used to detect corneal abnormalities that may be a contraindication to undergoing LASIK surgery.
  • Pupil size measurement: Your pupil size will likely be measured with a special device called an infrared pupillometer.

Separate medical tests, such as lab tests or an evaluation by a patient’s regular health care provider may or may not be necessary for LASIK surgery, depending on your eye doctor’s specific protocols.

A word from Verywell

You may decide to go for LASIK soon after hearing it’s an option for you, or you may want to take some time to make up your mind. Depending on the surgeon or medical facility, you may be waiting weeks or months for a scheduled surgery date.

Make sure you have the information you need to feel comfortable with your choice. Your health care provider can help you weigh the risks and benefits of the procedure and tell you what you can reasonably expect coming out of surgery in terms of improvement in your individual vision.

Verywell Health only uses high quality sources, including peer-reviewed studies, to support the facts in our articles. Read our editorial process to learn more about how we fact check and ensure our content is accurate, reliable and trustworthy.

  1. National Eye Institute. (July 2019). Refractive errors.

  2. American Board of Refractive Surgery. (July 2017). Your LASIK consultation: a deeper look at what to expect

  3. Wilkinson JM, Cozine EW, Khan AR. Refractive Eye Surgery: Helping Patients Make Informed Decisions About LASIK. Am Fam Physician. 2017 May 15;95(10):637-644.

  4. United States FDA. (July 2018). When is LASIK not for me?

  5. Wilkinson JM, Cozine EW, Khan AR. Refractive Eye Surgery: Helping Patients Make Informed Decisions About LASIK. Am Fam Physician. 2017 May 15;95(10):637-644.

  6. Wilkinson JM, Cozine EW, Khan AR. Refractive Eye Surgery: Helping Patients Make Informed Decisions About LASIK. Am Fam Physician. 2017 May 15;95(10):637-644.

  7. Boyd K. (December 2019). American Academy of Ophthalmology. LASIK — Laser eye surgery.

By Troy Bedinghaus, OD

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

Source link

Comments are closed.