LASIK – Laser eye surgery
LASIK (Laser-Assisted In Situ Keratomileusis) is the most well-known laser refractive surgery technique in the world. Its reputation stems from its precision and very rapid visual recovery. The laser procedure can correct myopia, hyperopia, astigmatism, and even presbyopia. The technique uses two lasers. The first creates the superficial corneal lenticule, which is then lifted and repositioned at the end of the procedure to act like a bandage. The second laser reshapes the cornea and corrects the refractive error. It is a reliable and precise surgical technique with 25 years of proven success. Visual recovery is very rapid, and dry eye is temporary.
What is Lasik?
LASIK allows the ophthalmologist to reshape the cornea so that light rays focus sharply onto the retina. The technique is used to treat myopia, hyperopia, and astigmatism. Through a monovision mechanism, presbyopia can be corrected after age 40.
The operation uses 2 lasers, which is why the procedure is slightly more expensive than PRK.
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The femtosecond laser – It allows for the creation of a corneal lenticule. The laser tip must make contact with your eye to be extremely precise.
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The Excimer laser – It allows for corneal reshaping similar to PRK. This laser procedure does not require contact with your eye.
The goal of LASIK is to correct your refractive error, that is, the vision problem for which you wear corrective lenses. LASIK eye surgery can eliminate or reduce your need for glasses or contact lenses.
Why choose LASIK?
If you have high myopia, significant astigmatism, or hyperopia, then LASIK is most likely the surgical technique of choice. The corneal lenticule acts like a bandage, smoothing the reshaped cornea. The healing process is therefore more reliable and faster than with PRK in these cases.
Therefore, LASIK is very useful in cases of:
Myopia greater than -6 diopters (debatable).
Astigmatism greater than -3 (debatable).
Hyperopia.
Presbyopia.
An operation with two decades of hindsight
LASIK was approved in 1998 by the FDA, the US health and drug regulatory agency. The technique had to demonstrate its safety and positive results to obtain approval. We now have nearly 25 years of experience with LASIK in Europe, making it a reliable and safe procedure.
Eligibility
To be eligible for LASIK surgery, you must meet certain conditions. Here are the main ones:
Be 20 years old (ideally 23 years old minimum).
Your glasses must not have changed by more than 0.50 over 3 years before age 25 and 2 years after age 25.
Your cornea must be more than 500µm thick.
The correction must leave more than 300µm of residual thickness after remodeling.
Your prescription must be amenable to LASIK treatment. The correction limits are generally: -10 for myopia, -6 for astigmatism, +6 for hyperopia.
Your visual expectations must be in line with the results that the operation will bring.
Contraindications and ineligibility
Some patients are not eligible for LASIK. These include patients with:
Unstable correction – particularly progressive myopia or astigmatism.
Extreme refractive error – Correction beyond the capabilities of laser surgery. In this case, a phakic intraocular lens (ICL) technique may be recommended.
Severe or uncontrolled dry eye.
A cornea that is too thin (< 500 µm)
Corneal dystrophy – Degeneration of the cornea.
Keratoconus – Abnormal and progressive astigmatism due to corneal fragility, resulting in a “hernia” of the cornea.
Unstable or advanced glaucoma.
A cataract affecting vision.
A significant corneal scar or sequela of a major abscess.
Uncontrolled diabetes.
Pregnancy or breastfeeding can cause vision problems because vision is not stable and the cornea thickens due to hormonal mechanisms.
Your ophthalmologist will look for any possible contraindications during the pre-operative assessment.
Lasik and sport
LASIK allows participation in all sports activities except contact sports (rugby, boxing, etc.). Indeed, although extremely strong once healed, the lenticule can shift in the event of severe eye trauma.
After Lasik surgery, you will be able to resume:
Gentle exercise after 1 week (elliptical trainer, treadmill, etc.).
Running and swimming after 15 days.
Intense physical activities with a risk of projectile injury (tennis, football, etc.) should be avoided after 1 month.
If you practice a contact or combat sport, PKR or SMILE will be the techniques of choice because no lens is at risk of moving.
Pre-operative assessment and examinations
The pre-operative assessment in refractive surgery is a crucial moment in order to demystify the operation, verify eligibility criteria and ensure the final satisfaction of the patient.
It will be checked during this pre-operative consultation:
Refraction – A precise vision test is performed with glasses worn and the correction is adjusted if necessary.
Clinical examination – We look for abnormal dry eye, cataracts or fundus abnormalities.
Topography – 3D analysis of your cornea to detect abnormal thinning or keratoconus.
Pachymetry – The thickness of your cornea is checked and the surgeon verifies, using scientific calculations, that it is sufficient for the necessary correction.
Pupillometry – The size of your pupil is checked in order to limit the risk of halos.
Cycloplegia – The correction is controlled with drops that relax accommodation (Skiacol) in order to be certain of the perfect correction.
Procedure for the Lasik procedure
Before the laser surgery
The pre-operative assessment is carried out at the office. Your follow-up care is also performed there. The laser surgery takes place at the refractive surgery center, where several ophthalmologists pool their resources to benefit from the latest machines and advancements.
If you decide to proceed, the surgeon's secretary will give you a quote, a consent form from the French Society of Ophthalmology (SFO), and a surgery date. Here are some tips to consider before the operation:
Contact your health insurance provider to assess potential reimbursement and your out-of-pocket expenses. Note: Social Security does not cover any costs.
Schedule a follow-up appointment with the surgeon the day after the procedure. However, you don't need to take time off work if you have a sedentary, computer-based job. If your job is manual or involves a risk of splashing or flying debris, plan to take at least five days off.
Do not wear your contact lenses the week before the procedure.
It is preferable to have someone accompany you on the day of the procedure.
On the day of the operation, carefully remove your makeup and wash your face with clean water and soap.
Do not tie your hair up or make a low ponytail so that you are comfortably positioned, lying down under the laser.
During LASIK – Procedure
The surgeon uses two lasers to correct your vision. Here's what will happen:
Your eye will be anesthetized with eye drops.
You will be positioned lying down under the first laser.
A blepharostat (eyelid support) will be placed to prevent any blinking.
The operation takes place on 2 lasers with different functions:
1st laser – The Femtosecond – This is the “cutting” laser.
The surgeon presses a lens onto your cornea.
You will feel a sensation of pressure or suction. At this point, your vision will become blurry.
The laser treatment lasts approximately 10 seconds, is painless and makes almost no noise.
The step is then repeated on the other eye.
2nd laser – Excimer – This is the corrective laser, it “remodels” the cornea.
The surgeon will establish strict sterile conditions. He will disinfect your face and eyes with Betadine.
A blepharostat keeps your eye open.
The lenticule created by the femtosecond laser is lifted and then the excimer treatment is performed.
The laser treatment lasts 10 to 20 seconds. It emits a buzzing sound and a smell of burnt hair may be present.
Once the laser treatment is complete, the lens (lenticle) is put back in place. It adheres immediately to your eye.
The treatment is then performed on the other eye.
Immediately after the operation, vision will already be clearer than before without correction.
Post-operative – Recovery and convalescence after LASIK
You will leave the operation with a pair of protective goggles or non-prescription sunglasses. These should be worn outdoors for 2 to 3 days.
Your eye may be slightly red due to the suction (eye contact during the first laser treatment). This is a benign subconjunctival hemorrhage.
Immediately after the operation, vision is already better than it was without glasses a few minutes before.
Your eyes will be sensitive and may itch for 2 to 3 days. However, there will be no intense pain or sleeplessness.
You will be able to return home 30 minutes after the procedure, preferably accompanied or otherwise by taxi.
Start treatment a few hours after the operation.
A check-up will be carried out by your surgeon or one of his assistants the day after the procedure.
Vision after LASIK
Over 90% of LASIK patients have vision better than 8/10 the day after surgery and 10/10 a few days later. Final vision frequently exceeds 12/10 without correction in myopic and astigmatic patients.
In the case of LASIK to correct hyperopia, visual recovery is slower. Near vision will be very satisfactory the day after the operation. However, distance vision will be disappointing. In most patients, this distance vision will improve within one to three months.
LASIK can also be used to treat presbyopia (PresbyLASIK). The technique used is monovision: the dominant eye is favored for distance vision (emmetropia) and the non-dominant eye for near vision (residual myopia). This imbalance, also called "switching," is tested beforehand with contact lenses. However, a short adaptation period may be necessary.
What are the risks of Lasik?
Like any surgical procedure, LASIK carries risks of dissatisfaction or complications which will be investigated and discussed by your surgeon.
Side effects are usually treatable and inconsequential. In rare cases, however, they can impair quality of life and become debilitating.
The main side effects, whether temporary or permanent, are:
Dry eye – routinely treated with moisturizing eye drops. This is the most common complication of LASIK.
Eye pain or discomfort.
A blurred, hazy or cloudy vision.
A sensation of chronic itching.
Glare and photophobia (sensitivity to light).
Halos (rings) or stars around the lights.
Myopic regression – Myopia continues to evolve.
Furthermore, with LASIK, your vision may be under-corrected or over-corrected. These issues can often be improved with glasses, contact lenses, or a further laser touch-up.
Rare but serious complications:
Corneal abscess – A serious infection of the cornea.
Ectasia – The thinned cornea becomes too fragile and deforms abnormally, leading to astigmatism and myopia.
Venous or arterial occlusion – Suction weakens an artery or vein in the retina by increasing intraocular pressure. The vessel becomes thrombosed and damages the retina.
Flap displacement or detachment – This is an extremely rare complication. However, in cases of significant trauma, the LASIK flap can shift or detach several years later. In this case, it must be repositioned urgently. If it is lost or too damaged, rigid contact lenses will be necessary to correct vision.
Dry eyes after LASIK
Dry eye is a common side effect of LASIK. This is due to the cutting of the corneal nerves during the creation of the flap with the femtosecond laser. In some patients, the nerves can take up to 3 years to regenerate.
Many patients feel the need to use moisturizing drops in the month following the procedure. Patients who use moisturizing drops for their entire lives are relatively rare.
Some patients experience severe dry eye, aggravated or triggered by the procedure. This can be treated with artificial tears, punctal plugs, cyclosporine, and scleral lenses.
Frequently Asked Questions
Who is a good candidate for LASIK surgery?
There are several eligibility criteria for Lasik. The main ones are:
From a patient's perspective:
The ideal age is between 23 and 40. After 40, the question of presbyLasik arises.
Vision must be stable, meaning it should not have changed by more than 0.50 diopters in 2 years.
The ophthalmologist also considers the following criteria:
The cornea must be regular and of sufficient thickness on ultrasound.
The eye should not show any signs of uncontrolled dry eye.
How long does a LASIK operation take?
The lasik operation lasts on average 15 to 20 minutes depending on your participation, the surgeon and the organization of the operating room.
Are there any risks or side effects associated with LASIK?
Yes… Like any surgery, LASIK carries risks, although they remain exceptional. The main risks are:
Dry eyes.
The luminous halos.
Refractive error requiring touch-up or the need to wear glasses again.
The infection, also called a corneal abscess.
Ectasia, or herniation of the cornea, due to excessive weakening.
What are the typical results of LASIK?
LASIK surgery generally results in a quick recovery. The typical recovery follows this pattern:
No intense pain.
Tearing and discomfort for 3 to 5 days.
Vision at 8/10 after 24 hours and 10/10 after 3 to 7 days.
Dry eyes lasting 0 to 3 months.
Bright halos when driving at night for corrections greater than -6 diopters.
This evolution is essentially valid for myopia and may be different in the case of correction of strong astigmatism or hyperopia.
How long does dry eye last after LASIK?
Dry eye typically lasts 1 to 3 months after Lasik surgery.
How quickly does vision return?
- In the case of correction of myopia or astigmatism, vision will be clear from the day after the operation.
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If hyperopia is corrected, near vision will be clear the next day, but distance vision will be disappointing for 1 to 3 months.
Can LASIK correct all types of vision problems?
Yes, LASIK can correct all refractive errors, meaning all vision problems correctable with glasses or contact lenses: myopia, hyperopia, astigmatism, and presbyopia. These conditions can also be corrected in combination, for example: myopia + astigmatism + presbyopia.
However, be aware that Lasik does not correct other eye conditions such as cataracts, glaucoma or retinal diseases.