Updated on  October 31, 2024
4 min read

How Bad Can Your Vision Be for LASIK?

6 sources cited
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LASIK (laser-assisted in situ keratomileusis) is a type of refractive surgery that corrects vision. It is a common procedure for people who wear glasses or contact lenses. 

Let’s discuss the requirements for LASIK surgery and who shouldn’t get it. We’ll also give other vision correction options if you don’t qualify for LASIK.

Is My Vision Too Bad For LASIK?

Not all people who have vision problems should undergo LASIK surgery. There are specific qualifications you must meet. These include: 

  • Having up to -12.0 diopters of nearsightedness
  • Having up to 6.0 diopters of astigmatism
  • Having up to +6.0 diopters of farsightedness
  • Diopters are not lessened by more than 0.5 within one year of the procedure

What are Refractive Errors and Diopters?

A diopter is a unit used to indicate the strength of your lens. Meanwhile, refractive errors are vision problems that occur when the cornea and lens don’t bend light correctly.

This means the cornea and/or lens are irregularly shaped, resulting in vision problems such as:

  • Nearsightedness. Clear and distinct vision of nearby objects but not of objects far away from you.
  • Farsightedness. Clear and distinct vision of far objects but not of objects close to you.
  • Astigmatism. Causes objects to appear blurry, regardless of their distance.
  • Presbyopia. An age-related refractive error that causes gradual loss of close-up vision.

LASIK Eye Surgery Requirements

Aside from the qualifications mentioned above, you should also consider other factors before undergoing laser eye treatment. These include:

1. Eye Health

Your eyes must be healthy before undergoing LASIK surgery. For example, eye infections and chronic dry eyes need to be corrected before the procedure. LASIK is not an option if you have a degenerative eye disease.

2. Physical Health

During LASIK surgery, the doctor will make an incision into one or both eyes. Your body needs to be in good health to endure this process and heal properly. Certain conditions like diabetes can affect the healing process and increase the risk of complications.

3. Age

You have to be 18 years or older to undergo LASIK. However, optometrists and ophthalmologists usually recommend waiting until your mid-20s (or older). 

Vision prescriptions typically change and evolve in your younger years. Waiting until you are at least 25 will make LASIK surgery more effective. 

4. Vision Stability

You must have a vision prescription that has not changed over the last 12 months. LASIK will only correct your current eye prescription. If your vision prescription is not stable and continues to change, the procedure will be less effective. 

5. Corneal Thickness

Because LASIK reshapes the cornea, your cornea must be thick enough to sculpt. LASIK is only safe for corneas that are thick enough to be functional again after the surgery. 

The average corneal thickness is between 540 µm to 560 µm. Corneas thinner than 540µm may not be suitable for LASIK surgery.

Who Shouldn’t Get LASIK?

Typically, people under 18 years old shouldn’t get LASIK because their vision often changes during adolescence and will likely change again after surgery.

People who are nursing or pregnant should also avoid getting LASIK because hormone fluctuations can cause vision changes. Additionally, medications administered during LASIK might be harmful to the fetus, so the procedure isn’t safe if you’re pregnant. 

Lastly, taking certain prescription drugs, such as steroids, can interfere with the outcome of the procedure. Talk to your eye doctor about any prescription medications that you’re taking beforehand.

Conditions that Can Affect LASIK

You shouldn’t get LASIK when you have dry eye syndrome because it can increase the risk of post-LASIK discomfort and worsen the condition. Additionally, people with the following conditions shouldn’t undergo LASIK:

  • Diabetes
  • Rheumatoid arthritis
  • Lupus
  • Glaucoma
  • Cataracts
  • Eye injuries or infections, which can leave corneal scarring
  • Have Large Pupils

Pupil dilation should only reach 6 mm. But, if your pupil dilates 7 to 8 mm in the dark, this might have a negative effect on your vision if you pursue LASIK.

What to Expect During a LASIK Consultation

You can expect a comprehensive eye exam when you schedule a LASIK consultation. Your doctor will assess whether or not you are a good candidate for the surgery.

During the eye exam, your doctor will: 

  • Determine your prescription
  • Evaluate your eye health
  • Examine the interior of your eyes 
  • Get the exact measurement of the refractive error
  • Other measurements as needed

Other Vision Correction Options 

There are other treatment options available, such as: 

Consult your eye doctor or surgeon to determine the best vision correction option for you.

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How Bad Can Your Vision Be for LASIK?
Vision Center Podcast
Updated on  October 31, 2024
6 sources cited
Updated on  October 31, 2024
  1. What is LASIK?” US Food & Drug Administration, 2021.
  2. Bamashmus et al. “Functional outcome and patient satisfaction after laser in situ keratomileusis for correction of myopia and myopic astigmatism.” Middle East African journal of ophthalmology, 2015.
  3. What are the risks and how can I find the right doctor for me?” US Food & Drug Administration, 2018.
  4. Boyd, K. “LASIK — Laser Eye Surgery.” American Academy of Ophthalmology, 2024. 
  5. Wilkinson et al. “Refractive Eye Surgery: Helping Patients Make Informed Decisions About LASIK.” American Family Physician, 2017.
  6. LASIK & Advanced Vision Correction Frequently Asked Questions.” Flaum Eye Institute.
The information provided on VisionCenter.org should not be used in place of actual information provided by a doctor or a specialist.