LASIK: Risks, Complications and Side Effects

LASIK Eye Surgery: Understanding Risks, Complications, and Safety

No surgery is without risks and possible complications and LASIK Eye Surgery is no different in that respect. At Trusted LASIK Surgeons®, we believe patients can minimize these risks by selecting a highly qualified LASIK Surgeon: one who can offer you the proper diagnosis, recommend the treatment best suited to your eyes and your vision, and who has the proven experience and expertise to perform the laser eye surgery or another vision correction procedures you choose.

To view a video on potential LASIK complications, please click the "play" button below:

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General Information About LASIK Surgery Risks

While the vast majority of LASIK and other laser vision correction procedures like PRK, ASA and SMILE EYE Surgery are successful and complications are rare, it is important to be aware of potential outcomes.

• Serious complications, such as a significant loss of vision that cannot be corrected with glasses or contacts, are extremely uncommon.
• Minor side effects, such as feeling of dryness, temporary visual disturbances like glare, halos, or starbursts, are more common in the initial post-operative period.
• These common side effects are typically temporary and tend to subside or resolve on their own within the first few weeks or months as the eye heals.
• In some cases, side effects or complications may persist for a longer period, or new issues may arise. Many of these can be managed with additional treatment, such as eye drops, glasses, or in some cases, an enhancement procedure.

A comprehensive understanding of potential risks, combined with a thorough pre-operative evaluation and the selection of an experienced surgeon, significantly contributes to a safe and successful LASIK experience. For comprehensive information about the LASIK procedure itself, please visit our LASIK Eye Surgery Discussion page.

Minimizing Risks by Choosing a Trusted LASIK Surgeons®

Considering LASIK eye surgery is a significant step towards achieving clear vision and reducing reliance on glasses or contact lenses. Like any surgical procedure, LASIK carries potential risks and complications. At Trusted LASIK Surgeons®, we believe that the best way to minimize these risks is by choosing a highly qualified and experienced LASIK surgeon.

An expert surgeon can provide a proper diagnosis, determine if LASIK or another vision correction procedure is best suited for your specific eyes and visual needs, and has the proven experience and expertise to perform the surgery with the highest level of precision and safety. Understanding potential risks and discussing them openly with a trusted professional is key to making an informed decision about LASIK.

Potential Risks and Complications of LASIK Eye Surgery

While LASIK is a highly refined procedure, potential risks and complications exist. These can range from temporary side effects to, in very rare instances, more serious issues. Based on information commonly included in informed consent processes and clinical studies, potential risks and complications can include:

Vision-Threatening or Potentially Serious Complications (Rare)

• Equipment Malfunction: The laser or microkeratome/femtosecond laser could malfunction during the procedure, potentially affecting the outcome.
• Flap Complications: Issues during the creation of the corneal flap, such as an incomplete flap, a free cap (entire portion cut off), or a flap that is too thin. While rare with modern techniques, these can occur and may require postponing the laser treatment or further procedures. Irregular healing of the flap can also lead to a distorted cornea.
• Infection: Although uncommon, a serious infection inside or outside the eye is possible after any surgery. Severe infection could potentially lead to scarring and vision loss, even requiring a corneal transplant in very rare cases. Mild infections are usually treatable with antibiotics.
• Ectasia (Corneal Thinning/Bulging): A rare but serious complication where the cornea weakens and bulges forward after LASIK, causing distorted vision. This risk is significantly increased in patients who are not properly screened for conditions like keratoconus or who have thin corneas.
• Keratoconus Progression: While not a direct complication of LASIK, if a patient has underlying, undiagnosed keratoconus (a progressive corneal disease), LASIK can potentially worsen the condition due to the removal of corneal tissue and weakening of the cornea. Proper pre-operative screening is crucial to identify patients at risk.
• Perforation: In extremely rare instances, a perforation of the cornea or other severe injury to the eye can occur during the procedure, with potentially devastating consequences including vision loss or loss of the eye.
• Retinal Issues: Very rarely, conditions like retinal detachment can occur after LASIK, particularly in highly nearsighted individuals who are already at a slightly increased risk for this condition.
• Cataract Formation or Other Internal Eye Issues: While LASIK is performed on the cornea, very rare complications involving the internal structures of the eye, such as hemorrhage or issues affecting the natural lens or retina, could theoretically occur in rare circumstances.

Non-Vision Threatening or Potentially Temporary Side Effects

• Dry Eye: A common side effect where the eyes feel drier than usual after surgery. This can range from mild irritation to significant discomfort and may affect vision quality. Dry eye symptoms can last for several months and, in rare cases, may be chronic. Treatment often involves artificial tears, punctal plugs, or other dry eye therapies.
• Visual Disturbances (Glare, Halos, Starbursts, Double Vision): These are common side effects, particularly noticeable at night or in dim light. Glare is excessive brightness, halos are rings around lights, and starbursts are streaks radiating from lights. Double vision (diplopia) can also occur. These symptoms often diminish as the eye heals, typically resolving within weeks or months. In some patients, especially those with large pupils or high corrections, these symptoms may persist permanently, potentially affecting night driving.
• Undercorrection or Overcorrection: The laser treatment may not achieve the exact desired correction, leaving the patient still slightly nearsighted, farsighted, or with residual astigmatism.
• Induced Astigmatism: Uneven healing or laser treatment can sometimes create or increase astigmatism.
• Fluctuating Vision: Vision may vary throughout the day, particularly in the initial healing period.
• Regression: Over time, a portion of the initial correction may be lost, and the patient's vision may return slightly towards their original prescription, potentially requiring glasses or contacts again.
• Anisometropia: If only one eye is treated at a time, or if the outcomes differ between the two eyes, a significant difference in prescription between the eyes can occur, leading to eyestrain and difficulty with depth perception until the second eye is treated or managed.
• Corneal Sensation Changes: Reduced corneal sensation or nerve healing issues can contribute to dry eye and impact the eye's natural protective reflexes.
• Flap Wrinkles or Displacement: The corneal flap can sometimes shift or develop wrinkles after surgery, potentially requiring a surgeon to lift and reposition the flap.
• Epithelial Ingrowth: Cells from the surface layer of the cornea (epithelium) can grow underneath the flap, sometimes requiring the flap to be lifted and the cells removed.
• Pain or Foreign Body Sensation: Some discomfort is normal in the immediate post-operative period, usually lasting only a day or two.
• Increased Sensitivity to Light (Photophobia): Common temporarily after surgery.
• Need for Glasses/Contacts or Enhancement: Even after a successful procedure, some patients may still need glasses or contact lenses for certain activities, or require a second laser procedure (enhancement) to fine-tune the result. An enhancement depends on sufficient remaining corneal tissue.
• Weakened Cornea: While rare with modern flap techniques, the creation of a corneal flap theoretically creates a plane of weakness, making the eye slightly more vulnerable to traumatic injury compared to an unoperated eye, at least initially. Protective eyewear during sports is advisable.

This list covers many potential risks and side effects, but it may not be exhaustive. Your surgeon will discuss all relevant risks based on your individual evaluation.

Factors That May Increase Your Risk of Complications

Certain factors can increase a patient's risk of complications from LASIK or may make them a better candidate for an alternative procedure like PRK, ASA, SMILE Eye Surgery, or a lens implant (such as RLE/CLE or EVO ICLE). A thorough pre-operative evaluation by a qualified surgeon is essential to identify these factors.

Factors that may increase your risk or affect candidacy include:

• Autoimmune disorders (e.g., Lupus, Rheumatoid Arthritis) or conditions that compromise the immune system.
• Unstable Refraction: Recent changes in your glasses or contact lens prescription (indicating vision is still changing, common in younger adults). Vision should be stable for at least a year before LASIK.
• Hormonal Changes: Vision changes related to pregnancy, nursing, or certain medications.
• Pre-existing Dry Eye Disease: Significant dry eye symptoms can be worsened by LASIK.
• Certain Corneal Conditions: Including Keratoconus, forme fruste keratoconus (subclinical keratoconus), corneal scarring, or certain dystrophies or degenerations.
• Other Eye Diseases: Such as moderate to severe glaucoma or uncontrolled eye infections.
• Thin Corneas: Insufficient corneal thickness may preclude LASIK or increase the risk of ectasia.
• Large Pupils: May increase the risk of night vision symptoms like glare and halos.
• Severe Nearsightedness, Farsightedness, or Astigmatism: Very high prescriptions may be outside the safe or effective range for LASIK and could increase certain risks or lead to less predictable outcomes.

Your surgeon will carefully evaluate these and other factors during your consultation to determine if you are a suitable LASIK candidate and discuss the procedure's safety profile for your unique eyes.

The Importance of a Thorough Pre-Operative Evaluation

The most critical step in minimizing risks and achieving a successful outcome with LASIK is the comprehensive pre-operative eye examination. A highly qualified LASIK surgeon will perform detailed tests and measurements to assess your:

• Refractive error (prescription) and its stability.
• Corneal shape (topography) to check for irregularities or signs of keratoconus.
• Corneal thickness (pachymetry) to ensure adequate tissue for flap creation and laser ablation.
• Pupil size.
• Overall eye health, including checks for dry eye, glaucoma, or retinal issues.
• Medical history to identify any systemic conditions or medications that could affect healing or outcomes.

Based on this thorough evaluation, your surgeon will determine if you are a good candidate for LASIK and discuss your personalized risk profile. If LASIK is not the best option, they can recommend a more suitable vision correction procedure.

Informed Consent for LASIK Surgery

Before undergoing LASIK, you will participate in a detailed informed consent process. This involves your surgeon explaining the procedure, its expected benefits, alternative treatments, and potential risks and complications, allowing you to ask questions and ensure you fully understand what the surgery entails. You will be asked to sign a consent form acknowledging that you have received and understand this information.

Reviewing a sample informed consent form can be helpful for understanding the types of risks that will be discussed. While your surgeon's consent form may differ in wording, it will cover the essential information regarding potential risks and side effects of LASIK surgery. We have included a sample Informed Consent Form for LASIK at the bottom of this page. 

All-Laser (Bladeless) LASIK. If you are considering “all laser” or bladeless LASIK, please visit our All Laser with IntraLase Risks and Complications discussion.

The consent your surgeon uses may be different than this example but we believe this consent covers the main risks. 

Bilateral Simultaneous LASIK. If you are considering have LASIK on both eyes at the same time, please see our Bilateral Simultaneous LASIK Risks and Complications discussion. 

Why Choose a LASIK Surgeon Featured in the Trusted LASIK Surgeons® Directory?

Choosing a highly qualified and experienced eye surgeon is the single most important factor in minimizing the risks associated with LASIK and achieving a safe and successful outcome. Surgeons featured in the Trusted LASIK Surgeons® Directory meet stringent qualification standards based on objective measures of their extensive experience, professional accomplishments, and recognition by their peers in ophthalmology. This rigorous screening process is designed to help you find truly expert surgeons dedicated to patient care and optimal results.

Surgeons in our directories have significant experience performing a high volume of LASIK procedures and managing a wide range of cases. Their extensive experience means they are highly skilled in:

1. Accurately identifying suitable candidates through comprehensive evaluations, recognizing factors that might increase risk.
2. Performing the LASIK procedure with precision and expertise, using advanced technology.
3. Managing potential complications or side effects should they arise.
4. Recommending the most appropriate alternative procedure if LASIK is not the safest or most effective option for your eyes (e.g., PRK, ASA, SMILE, RLE, EVO ICL).

Choosing an expert surgeon from our network provides confidence that you are entrusting your vision to a professional with a proven track record in patient safety and successful outcomes.

Ready to discuss your LASIK risks and candidacy with a highly qualified surgeon?

Understanding risks and suitability for LASIK is best done through a personalized consultation. Use our directories to connect with a trusted expert near you who can perform a thorough evaluation and discuss the potential risks and benefits as they apply to you.

Find a Trusted LASIK Surgeons®

Looking for a Cataract or Lens Implant Surgeon?

Find a Trusted Cataract Surgeons®

Important Note: While surgeons listed in our Trusted LASIK Surgeons® and Trusted Cataract Surgeons® directories are highly qualified in various vision correction procedures, not all surgeons listed perform every specific procedure or use every technology mentioned on our website. Visitors should always confirm directly with the surgeon's office the specific procedures and technologies they offer and to schedule a consultation to discuss their candidacy and risks.

To learn more about the screening process and standards we use to screen and qualify surgeons please visit: 

How Are LASIK Surgeons Screened by Trusted LASIK Surgeons®? 

Frequently Asked Questions (FAQs)

Q: Is LASIK surgery safe? Yes, LASIK is widely considered a safe and effective surgical procedure, with a very high success rate and low incidence of serious complications when performed on suitable candidates by experienced surgeons.

Q: What are the most common side effects after LASIK? Common temporary side effects include dry eye, glare, halos, and starbursts, especially at night. These often improve over weeks or months.

Q: Can LASIK cause blindness? Loss of vision from LASIK is extremely rare, but like any surgery, it carries a minimal risk of serious complications.

Q: What is LASIK ectasia? Ectasia is a rare complication where the cornea weakens and bulges after LASIK, causing distorted vision. It is often related to performing LASIK on unsuitable eyes (e.g., with thin corneas or undiagnosed keratoconus).

Q: Will I have dry eyes after LASIK? Dry eye symptoms are common temporarily after LASIK. They usually improve with time and treatment, but can be chronic in rare cases.

Q: Can I drive at night after LASIK? Temporary glare and halos can affect night vision and driving. While often resolving, these symptoms can be permanent for some. Do not drive until your vision is adequate.

Q: How can I minimize the risks of LASIK? Minimizing risks involves having a thorough pre-operative evaluation to ensure you are a good candidate and choosing a highly qualified and experienced LASIK surgeon.

Conclusion

While it's important to be aware of the potential risks and complications associated with LASIK eye surgery, serious issues are rare, and common side effects are usually temporary. The safety and success of LASIK are highly dependent on proper patient selection and surgical expertise.

Choosing a highly qualified surgeon from the Trusted LASIK Surgeons® or Trusted Cataract Surgeons® directories provides the best assurance that you will receive a thorough evaluation to determine your candidacy and a skillfully performed procedure, thereby minimizing potential risks. Don't let concerns about risks prevent you from exploring your options. Consult with a trusted expert to understand if LASIK is safe and appropriate for your eyes and to discuss how potential risks are managed.

Informed Consent for LASIK Surgery (Sample Form)

Introduction

This information is being provided to you so that you can make an informed decision about the use of a device known as a microkeratome, combined with the use of a device known as an excimer laser, to perform LASIK (or Laser In-Situ Keratomileusis). LASIK is one of a number of alternatives for correcting nearsightedness, farsightedness and astigmatism. In LASIK, the microkeratome is used to shave the cornea to create a flap. The flap then is opened like the page of a book to expose tissue just below the cornea’s surface. Next, the excimer laser is used to remove ultra-thin layers from the cornea to reshape it to reduce nearsightedness. Finally, the flap is returned to its original position, without sutures.

LASIK is an elective procedure: There is no emergency condition or other reason that requires or demands that you have it performed. You could continue wearing contact lenses or glasses and have adequate visual acuity. This procedure, like all surgery, presents some risks, many of which are listed below. You should also understand that there may be other risks not known to your doctor, which may become known later. Despite the best of care, complications and side effects may occur; should this happen in your case, the result might be affected even to the extent of making your vision worse.

Alternatives to LASIK

If you decide not to have LASIK, there are other methods of correcting your nearsightedness (myopia), farsightedness (hyperopia) or astigmatism (blurred vision). These alternatives include, among others, eyeglasses, contact lenses and other refractive surgical procedures.

Patient Consent

In giving my permission for LASIK, I understand the following: The long-term risks and effects of LASIK are unknown. I have received no guarantee as to the success of my particular case. I understand that the following risks are associated with the procedure:

Vision Threatening Complications

1. I understand that the microkeratome or the excimer laser could malfunction, requiring the procedure to be stopped before completion. Depending on the type of malfunction, this may or may not be accompanied by visual loss.

2. I understand that, in using the microkeratome, instead of making a flap, an entire portion of the central cornea could be cut off, and very rarely could be lost. If preserved, I understand that my doctor would put this tissue back on the eye after the laser treatment, using sutures, according to
the ALK procedure method. It is also possible that the flap incision could result in an incomplete flap, or a flap that is too thin. If this happens, it is likely that the laser part of the procedure will have to be postponed until the cornea has a chance to heal sufficiently to try to create the flap
again.

3. I understand that irregular healing of the flap could result in a distorted cornea. This would mean that glasses or contact lenses may not correct my vision to the level possible before undergoing LASIK. If this distortion in vision is severe, a partial or complete corneal transplant might be
necessary to repair the cornea.

4. I understand that it is possible a perforation of the cornea could occur, causing devastating complications, including loss of some or all of my vision. This could also be caused by an internal or external eye infection that could not be controlled with antibiotics or other means.

5. I understand that mild or severe infection is possible. Mild infection can usually be treated with antibiotics and usually does not lead to permanent visual loss. Severe infection, even if successfully treated with antibiotics, could lead to permanent scarring and loss of vision that may
require corrective laser surgery or, if very severe, corneal transplantation or even loss of the eye.

6. I understand that I could develop keratoconus. Keratoconus is a degenerative corneal disease affecting vision that occurs in approximately 1/2000 in the general population. While there are several tests that suggest which patients might be at risk, this condition can develop in patients
who have normal preoperative topography (a map of the cornea obtained before surgery) and pachymetry (corneal thickness measurement) . Since keratoconus may occur on its own, there is no absolute test that will ensure a patient will not develop keratoconus following laser vision correction. Severe keratoconus may need to be treated with a corneal transplant while mild keratoconus can be corrected by glasses or contact lenses.

7. I understand that other very rare complications threatening vision include, but are not limited to, corneal swelling, corneal thinning (ectasia), appearance of “floaters” and retinal detachment, hemorrhage, venous and arterial blockage, cataract formation, total blindness, and even loss of my eye. 

Non-Vision Threatening Side Effects

8. I understand that there may be increased sensitivity to light, glare, and fluctuations in the sharpness of vision. I understand these conditions usually occur during the normal stabilization period of from one to three months, but they may also be permanent.

9. I understand that there is an increased risk of eye irritation related to drying of the corneal surface following the LASIK procedure. These symptoms may be temporary or, on rare occasions, permanent, and may require frequent application of artificial tears and/or closure of the tear duct openings in the eyelid.

10. I understand that an overcorrection or undercorrection could occur, causing me to become farsighted or nearsighted or increase my astigmatism and that this could be either permanent or treatable. I understand an overcorrection or undercorrection is more likely in people over the age of 40 years and may require the use of glasses for reading or for distance vision some or all of the time.

11. After refractive surgery, a certain number of patients experience glare, a “starbursting” or halo effect around lights, or other low-light vision problems that may interfere with the ability to drive at night or see well in dim light. The exact cause of these visual problems is not currently known; some ophthalmologists theorize that the risk may be increased in patients with large pupils or high degrees of correction. For most patients, this is a temporary condition that diminishes with time or is correctable by wearing glasses at night or taking eye drops. For some patients, however, these visual problems are permanent. I understand that my vision may not seem as sharp at night as during the day and that I may need to wear glasses at night or take eye drops. I understand that it is not possible to predict whether I will experience these night vision or low light problems, and that I may permanently lose the ability to drive at night or function in dim light because of them. I understand that I should not drive unless my vision is adequate.

12. I understand that I may not get a full correction from my LASIK procedure and this may require future enhancement procedures, such as more laser treatment or the use of glasses or contact lenses.

13. I understand that there may be a “balance” problem between my two eyes after LASIK has been performed on one eye, but not the other. This phenomenon is called anisometropia. I understand this would cause eyestrain and make judging distance or depth perception more difficult. I understand that my first eye may take longer to heal than is usual, prolonging the time I could experience anisometropia.

14. I understand that, after LASIK, the eye may be more fragile to trauma from impact. Evidence has shown that, as with any scar, the corneal incision will not be as strong as the cornea originally was at that site. I understand that the treated eye, therefore, is somewhat more vulnerable to all varieties of injuries, at least for the first year following LASIK. I understand it would be advisable for me to wear protective eyewear when engaging in sports or other activities in which the possibility of a ball, projectile, elbow, fist, or other traumatizing object contacting the eye may be high.

15. I understand that there is a natural tendency of the eyelids to droop with age and that eye surgery may hasten this process.

16. I understand that there may be pain or a foreign body sensation, particularly during the first 48 hours after surgery.

17. I understand that temporary glasses either for distance or reading may be necessary while healing occurs and that more than one pair of glasses may be needed.

18. I understand that the long-term effects of LASIK are unknown and that unforeseen complications or side effects could possibly occur.

19. I understand that visual acuity I initially gain from LASIK could regress, and that my vision may go partially back to a level that may require glasses or contact lens use to see clearly.

20. I understand that the correction that I can expect to gain from LASIK may not be perfect. I understand that it is not realistic to expect that this procedure will result in perfect vision, at all times, under all circumstances, for the rest of my life. I understand I may need glasses to refine my vision for some purposes requiring fine detailed vision after some point in my life, and that this might occur soon after surgery or years later.

21. I understand that I may be given medication in conjunction with the procedure and that my eye may be patched afterward. I therefore, understand that I must not drive the day of surgery and not until I am certain that my vision is adequate for driving.

22. I understand that if I currently need reading glasses, I will still likely need reading glasses after this treatment. It is possible that dependence on reading glasses may increase or that reading glasses may be required at an earlier age if I have this surgery.

23. Even 90% clarity of vision is still slightly blurry. Enhancement surgeries can be performed when vision is stable UNLESS it is unwise or unsafe. If the enhancement is performed within the first six months following surgery, there generally is no need to make another cut with the microkeratome.  The original flap can usually be lifted with specialized techniques. After 6 months of healing, a new LASIK incision may be required, incurring greater risk. In order to perform an enhancement surgery, there must be adequate tissue remaining. If there is inadequate tissue, it may not be possible to perform an enhancement. An assessment and consultation will be held with the surgeon at which time the benefits and risks of an enhancement surgery will be discussed.

24. I understand that, as with all types of surgery, there is a possibility of complications due to anesthesia, drug reactions, or other factors that may involve other parts of my body. I understand that, since it is impossible to state every complication that may occur as a result of any surgery, the list of complications in this form may not be complete. 

For Presbyopic Patients (those requiring a separate prescription for reading):

The option of monovision has been discussed with my ophthalmologist.

Patient’s Statement of Acceptance and Understanding

The details of the procedure known as LASIK have been presented to me in detail in this document and explained to me by my ophthalmologist. My ophthalmologist has answered all my questions to my satisfaction. I therefore consent to LASIK surgery on: