Refractive surgery – See without glasses or contact lenses
Refractive surgery encompasses all eye procedures using lasers or implants that allow patients to live without glasses or contact lenses. These procedures correct vision problems such as myopia , astigmatism , hyperopia , and presbyopia . Refractive surgery employs three main techniques, depending on the patient's age and refractive error: laser surgery ( LASIK , PRK , SMILE ), clear lens implantation ( Prelex ), and phakic intraocular lens (ICL) implantation . These procedures are safe, effective, and have a long track record. While extremely beneficial and satisfying, their cost is primarily borne by the patient or their supplemental health insurance.
What is refractive surgery?
Refractive surgery refers to eye operations that allow people to live without glasses or contact lenses. These operations can correct myopia, astigmatism, hyperopia, presbyopia, and even several of these vision problems simultaneously. Modern surgical techniques have benefited from over 20 years of experience! They are reliable, reproducible, and effective.
Laser surgery is the dominant technique: LASIK, PRK, and Relex SMILE. While less common, implant surgery using phakic or Prelex (clear lens) implants is less frequent but yields excellent results when laser surgery reaches its limits.
Refractive surgery techniques
Refractive surgery techniques can correct or compensate for a large number of refractive errors. The main techniques can be summarized as follows:
Refractive lasers
LASIK – The most well-known method uses 2 lasers to create a lenticule followed by corrective treatment.
PKR (and trans-PKR) – Non-contact technique, simple, fast, effective and physiological, but with a slower recovery.
SMILE – Presented as the evolution of Lasik, it has many advantages but remains little known to the general public.
PRESBY LASIK – This is an evolution of Lasik designed to compensate for presbyopia after 40-45 years of age.
Corrective implants
ICL – Phakic implants – Designed to correct extreme myopia that cannot be treated with laser. A corrective lens is placed in your eye.
PRELEX – Clear Lens – This involves bringing forward cataract surgery to correct vision before it is impaired. A multifocal implant corrects both distance and near vision.
Laser surgeries – Excimer and femtosecond lasers
Laser surgery is the method generally referred to when discussing refractive surgery. Its main advantage lies in the use of a laser (excimer type +/- femtosecond) which reshapes the cornea (the anterior tissue of the eye) without penetrating the eyeball. It therefore differs from intraocular surgery, which is unavoidable when implanting a lens.
The risks associated with laser surgery are significantly reduced compared to those of intraocular surgery, particularly regarding infection. Furthermore, it preserves the accommodative function (focusing) of the natural lens. This is why this technique, up to the age of approximately 55-60, is the preferred procedure for correcting myopia, hyperopia, astigmatism, and presbyopia.
There are two main methods: LASIK and PRK (described below). SMILE is a third, less well-known method, but presented as the future of LASIK. Depending on your situation, the surgeon may recommend one or the other method (LASIK or PRK). Sometimes both. These procedures are performed by the center's refractive surgeons.
Eligibility criteria
Laser refractive surgery is suitable for patients with the following characteristics:
Age over 20 and under 60.
Stable ametropia for at least 3 years (correction unchanged).
Myopia less than -10 diopters.
Hyperopia less than +6 diopters.
Astigmatism less than -6 diopters.
Presbyopia.
What can we expect from surgery?
In cases of myopia, hyperopia, and astigmatism, surgery should correct your vision problem. It will allow you to do without corrective lenses until the age of presbyopia (around 45 years old), after which correction for near vision is often essential.
Myopia – This is the most common refractive surgery. It is offered for values between approximately -1.00 and -10.00 diopters and gives very satisfactory results.
Hyperopia – This procedure is offered for prescriptions ranging from approximately +1.5 to +6.0. It carries a higher risk of regression than myopia surgery.
Astigmatism – In isolation, astigmatism is corrected for values between approximately -1.5 and -6.00 diopters. It can also be corrected during a procedure for myopia, hyperopia, or presbyopia.
Presbyopia – In presbyopia surgery, the goal is to reduce dependence on corrective lenses by increasing depth of field. Daily life will be possible 80% of the time without glasses, but situations involving prolonged reading or demanding distance vision (such as driving) will often require occasional correction. Halos are more pronounced after presbyopia surgery than after other types of surgery.
The pre-operative assessment
An essential pre-operative examination will allow for a precise interview, an examination and the performance of an OCT as well as a corneal topography to determine eligibility for one or the other of the techniques (LASIK or PRK).
It is particularly important to ensure that there are no contraindications to surgery: in particular, mild keratoconus, severe dryness, or participation in combat sports for LASIK.
Following this consultation, one or the other surgical procedure will be recommended, and in some cases, neither…
Examination under cycloplegia: Skiacol
A cycloplegic examination is also recommended to obtain an accurate refraction measurement. This can be performed during a second consultation if necessary.
After instillation of cycloplegic eye drops (Skiacol), the pupil will be dilated and vision will be blurred for several hours (longer than after a fundus examination). During this time, driving and work are not possible.
A history of epilepsy contraindicates the use of Skiacol (Cyclopentolate).
Contraindications
Who is surgery not for?
Presence of any ophthalmological history that threatens visual health.
Strabismus or amblyopia (6/10).
Severe dry eyes.
Keratoconus.
Systemic diseases: Lupus, rheumatoid arthritis, Graves' disease, Crohn's disease, Sjögren's syndrome…
What are the risks of surgery?
For a complete list of risks, please consult the information sheet from the French Society of Ophthalmology available here. In simple terms, here is what you need to understand about the risks of this surgery.
Dry eyes
All laser surgery will cause dry eyes, to a greater or lesser degree depending on the patient. 90% of them will be weaned off lubricating eye drops (artificial tears) 3 months after surgery.
In rare cases, the condition can persist for several months and require the long-term use of lubricating eye drops. Therefore, it is important to tell your doctor if you are experiencing dryness.
PKR is preferable in cases of proven drought.
The halos
The perception of halos (the impression of flashing lights), particularly at night, is possible after any refractive surgery. The risk is higher in cases of significant astigmatism and presbyopia surgery.
The regression
It is possible. Exceptionally as significant as the initial visual impairment, however, it can be estimated that approximately 10% of patients will wear glasses occasionally 10 years after surgery (excluding presbyopia).
Exposure to UV rays from the sun in the first few months following surgery is classically described as a risk factor for regression, which is why it is advisable to wear sunglasses for the first 3 months in case of sun exposure.
Prior stability of the correction is also important to reduce the risk of regression.
Presbyopia
The onset of presbyopia after refractive surgery at the usual age at which it occurs is a normal and expected process.
Like any emmetropic subject (vision not requiring optical correction), operated patients present with presbyopia at the age of about 45 years which will require wearing a correction for near vision.
Intraoperative complications
Correction errors, whether due to machine error or human intervention, are rare but possible. A retouch is sometimes offered.
Intraoperative complications sometimes leading to a change or cancellation of the procedure are rare but possible.
Early surgical complications
Early complications are characterized mainly by infections (treated with eye drops), SOS syndrome "Sand of Sahara" and Haze (treated with anti-inflammatory eye drops), and epithelial invasion (treated by surgical revision).
Late surgical complications
Late complications, in addition to the regression and dryness mentioned above, are mainly marked by corneal ectasia, irregular astigmatism linked to the weakening of the cornea, which is observed years after surgery.
Laser techniques: LASIK, PRK, SMILE
PRK – Classic and transepithelial Photorefractive Keratectomy
This surgical method involves applying the excimer laser beam to the corneal stroma after mechanical removal of the corneal epithelium. Transepithelial PRK, which avoids mechanical removal, is the procedure most commonly offered by surgeons at the center.
Visual recovery speed is less dramatic than with LASIK but better than with traditional PRK. This technique has the advantage of simplicity and a very low complication rate. Its drawback is a longer recovery time than LASIK: 3 to 4 days of downtime are to be expected.
Unlike LASIK, one to two days of pain are inevitable after surgery. A contact lens left in place for the first few days will need to be removed during a follow-up appointment. Complex prescriptions are often better corrected with LASIK.
But in the long term, both techniques give identical results in terms of visual acuity and a slight advantage to PRK in terms of dry eye.
LASIK – Laser-Assisted In-Situ Keratomileusis
This is a surgical method which consists of applying the Excimer laser beam to the corneal stroma after cutting a "corneal flap" with a Femto Second laser.
This method is painless, and visual recovery is almost immediate. Normal life can be resumed the very next day. Its advantages include rapid recovery, the absence of pain, and the ability to treat certain complex corrections.
Its disadvantages are the higher risk than in PRK of corneal ectasia (appearance of irregular astigmatism in the years following surgery) and the presence of a "corneal flap" which contraindicates this laser in practitioners of sports at risk of blows to the eyes, because the risk of displacement of the corneal flap is too great.
In patients with dry eyes, a risk of keratoconus or any other contraindication, surgery should be avoided or PRK should be preferred.
The SMILE – SMall Incision Lenticule Extraction
This is an evolution of LASIK. The surgical method involves creating a corneal lenticule using a femtosecond laser, which is then extracted from the cornea through an incision of less than 3mm. This means fewer corneal nerves are severed and visual recovery is very rapid (24-48 hours).
There is no pain during or after the operation. The risk of ectasia is similar to LASIK, but practicing combat sports is NOT contraindicated because there is no corneal flap.
The correction limits for myopia and astigmatism are slightly lower than with Lasik.
The operation
Whether it is LASIK, SMILE or trans-epithelial PRK, the operation is completely painless.
The surgery is performed under local anesthesia using eye drops and does not require anesthesia consultation or fasting.
The procedure lasts about twenty minutes for PKR, 25 for SMILE, about thirty for LASIK (because two separate lasers are needed).
A therapeutic lens is left in place only after PRK.
Post-operative care
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After the operation, you will be able to return home accompanied by a companion or by taxi.
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Sun protection is recommended during the first few months.
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In the case of LASIK or SMILE, the after-effects are painless. Vision is excellent the very next day.
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In the case of PRK, a few days of discomfort are inevitable, during which rest and patience are recommended. The lens implanted during PRK will be removed approximately 3 to 4 days after surgery.
Implant surgery – Endocular surgery
PRELEX – Clear lens surgery for refractive purposes
Cataract surgery is for patients who have cataracts (usually after the age of 50 to 60). The surgery involves removing the diseased lens (cataract) to restore vision and replacing it with an implant that will correct all or part of the refractive error.
The choice of implants:
To correct both distance and near vision without the need for optical correction, a multifocal implant may be offered.
The risk of perceiving halos is greater than with a monofocal implant, which is why it is contraindicated in cases of macular pathology ( diabetes , AMD , etc.).
Whether it is a monofocal or multifocal implant, astigmatism can be corrected by toricity (toric implant).
If multifocal implants are contraindicated, a monofocal implant can be used. You will need to choose whether to see without glasses for distance vision (in which case you will need corrective lenses for near vision) or for near vision (in which case you will need corrective lenses for distance vision). The best option should be determined with your surgeon before the procedure.
ICL – Phakic implant placement
The placement of phakic ICL implants is, like cataract surgery, an intraocular procedure.
The procedure involves inserting an implant into the anterior cavity of the eye (anterior chamber), in front of the lens which is left in place.
This surgery is most often intended for patients for whom more conventional laser surgery has been ruled out due to the presence of contraindications (see following paragraphs).
High myopia (beyond -10 diopters) is the most frequent indication for ICL.
This surgery gives excellent results, but its intraocular nature gives it the same risks of infection as those of cataracts: they are rare, but serious.
This is a procedure that must be discussed and considered at length by the patient because the risks of secondary glaucoma, cataracts and corneal dystrophy, although also rare, are real.
Frequently Asked Questions
At what age should you have myopia surgery?
It is possible to have myopia surgery once you are an adult, at any age; however, some nuances need to be considered:
For those aged 18 to 21, the procedure is only carried out in cases of professional necessity: law enforcement, sports, etc.
From 21 to 35 years old, the operation can be performed without worrying about presbyopia.
From the age of 35, it will be necessary to take into account the onset of presbyopia around 43-44 years of age, while maintaining a slight myopia in the non-dominant eye.
From the age of 43, myopia surgery is systematically combined with presbyopia treatment.
After 50-55 years of age, laser surgery may be abandoned in favor of an operation by implant placement (prelex).
Can myopia and astigmatism be corrected simultaneously?
Yes! Refractive surgery makes it possible to treat or compensate for all refractive errors at the same time: myopia, hyperopia, astigmatism and presbyopia.
Is it possible to have myopia surgery twice?
Yes! In case of myopia regression, it is possible to perform a laser touch-up if the thickness of the cornea allows it.