Small-incision lenticule extraction (SMILE)

Eligibility criteria

• Aged between 18 and 45
• Refractive error:
  • Has not changed for at least 1 year.
  • Spherical power up to −8 D
  • Astigmatism up to 4 D
• You have good vision in both eyes with your glasses or contact lenses.
• No other eye abnormalities
• Cornea of sufficient thickness and with normal curvature

Are you not eligible for laser eye surgery? An implantable contact lens (ICL) may be an alternative. 

Contraindications

You are not eligible for laser treatment in the following cases:

• During pregnancy or breastfeeding
• History of herpes keratitis
• Rheumatic conditions
• Corneal disease, such as keratoconus
• You only wear reading glasses.

Specific eyesight requirements apply to some professions, including the armed forces, police and aviation. Check carefully in advance whether laser treatment is permitted.

Screening/preliminary assessment

Several specialised examinations, including Pentacam, Sirius, MS-39 and Peramis, are needed to determine whether you are suitable for this treatment.

These examinations are usually performed beforehand at the laser centre.

Preparation

• Do not wear contact lenses in the weeks before your treatment:
  • Hard contact lenses: 3 weeks
  • Toric soft contact lenses: 3 weeks
  • Overnight contact lenses: 3 weeks
  • Soft contact lenses: 10 days
• Do not wear eyelash extensions
• You do not need to fast.
• Do not wear make-up on the day of the procedure.
• Bring the prescribed eye drops with you.
• Arrange transport on the day of the treatment.

Procedure

Duration: 20 minutes. The laser treatment itself takes 10 seconds. The treatment is painless.

• You are first given a sedative.
• You then lie down on the treatment table.
• The area around the eye is cleaned and disinfected.
• Anaesthetic eye drops are administered.
• A sterile drape is placed around your eye.
• Your eye is held open with an eyelid speculum. You cannot blink.
• During the treatment, you look at a point of light in the laser system.
  • First, a disc of corneal tissue, also known as a lenticule, is separated around its entire 360° circumference using the laser (A).
  • The laser then creates the small incision (B).
  • The surgeon opens the incision and removes the lenticule through the small incision (C).
• After the laser treatment, you will be given additional eye drops.

Aftercare

• Immediately after the operation, your vision will still be somewhat blurred. This will improve quickly over the following days.
• You will attend a follow-up examination the day after the operation.

Risks and complications

SMILE is a safe treatment. Possible adverse outcomes include:

• Under- or overcorrection: additional treatment can correct this. This additional treatment is included in the price during the first year after treatment, provided it can be performed safely.
• Regular or irregular astigmatism that may cause your vision to deteriorate. This does not always improve with glasses.
• Inflammation: treated with corticosteroid eye drops.
• Infection: treated with antibiotic eye drops.
• Lenticule rupture: this can usually be resolved during the same procedure. In rare cases, a second operation is required.

These complications usually do not cause permanent damage to your vision.

During the stabilisation period

Symptoms that often occur temporarily during the stabilisation period include:

• Increased sensitivity to light
• Glare
• Fluctuations in visual acuity
• Starbursts or halos around light sources in the dark
• Increased vulnerability of the eye: use eye protection during activities such as tennis, squash and martial arts.

These side effects almost always decrease over time.