Introduction  

mall incision lenticule extraction or SMILE is a laser-based procedure used in ocular surgery for the treatment of refractive errors. For a clear vision, light must pass through a person’s cornea and eye lens. They refract or bend the light and focus it on the retina. 

Where there is a refractive error, the shape of the cornea or lens prevents light from bending correctly. It causes blurred vision because the light is not well focused on the retina. With this procedure, the eye surgeon uses a laser to reshape the patient’s cornea. It improves the way light focuses on the retina. 

SMILE is ideal for people who are working or have an active lifestyle. This is because the procedure doesn’t involve creating a flap in the cornea such as LASIK or similar treatments. A person who is very active may dislodge the corneal flap by accident leading to problems.
For a patient to be eligible for the SMILE they must:

  • Be at least 22 years old
     
  • Have a healthy cornea 
     
  • Have a good eye health
     
  • Have a stable eyeglass prescription for at least 12 months
     
  • Have myopia between -1 and -8 diopters with minimal astigmatism
     

People with the following conditions are ineligible for SMILE:

  • Advanced glaucoma
     
  • Uncontrolled diabetes
     
  • A cataract affecting vision
     
  • Pregnant or nursing women
     
  • Corneal abrasions or disease
     
  • History of certain eye infections
     
  • A changing (unstable) refractive error
     
  • History of eye surgery or eye disease
     
  • Excessive scarring or keloid formation
     
  • Skin or other diseases that can affect healing
     

Small incision lenticule extraction is approved by the FDA for treatment of mild nearsightedness. More than a million SMILE procedures have been done worldwide with few complications.
 

Also Known As

SMILE
 

Purpose

SMILE is primarily used in the treatment of nearsightedness (myopia), a specific refractive error. The goal of the technique is to correct nearsightedness to improve the patient’s vision. It can reduce the need for contact lenses or eyeglasses. In some cases, the patient doesn’t need contact lenses or eyeglasses after treatment.
 

Preparation & expectation before Surgery

The ophthalmologist examines the patient’s to eyes determine whether they are a candidate for SMILE. He or she will:

  • Check pupil size
     
  • Measure nearsightedness
     
  • Check eye health
     
  • Measure and map the corneal surface
     

Before the procedure:

  • Topical anesthetics are applied
     
  • The surgeon places an eyelid holder on the eye to keep it from blinking
     
  • The laser is programmed with the measurements for the patient’s eye
     
  • A suction ring lifts and flattens the cornea and helps keep the eye from moving
     

It is important for the patient to discuss their expectation for SMILE with the surgeon. SMILE enables people to carry out their daily tasks without corrective lenses. The individuals may need to use lenses for some activities like reading and driving at night. People seeking perfect vision without corrective lenses may be disappointed.
 

Procedure

SMILE takes about 15 minutes. The eye surgeon uses a laser to cut a small lenticule (a disc- shaped tissue) in the cornea. He/she then uses the laser to make a tiny arc-shaped incision in the surface of the cornea, extracts the lenticule through the incision, and disposes of it. The procedure alters the shape of the cornea and improves nearsightedness. There is no need to stitch the incision; it heals within a few days. The patient experiences a sharper vision very fast.
 

After care, recovery, results

  • The surgeon will prescribe eye drop medicine
     
  • One must avoid getting water in the eyes for a few days
     
  • One can undertake most normal activities after a day or two
     
  • The patient should relax or plan to take a nap after the treatment
     
  • The patient will need to have someone drive them home after surgery
     
  • Vision may be blurry immediately after the SMILE surgery. It will improve over the next few days and weeks, as the cornea heals

 

Risks & complications

The risks associated with the procedure include:

  • Infection
     
  • Blindness
     
  • Under correction or overcorrection
     
  • Inflammation within the treated area
     
  • Debris where the lenticule was removed
     
  • Halos and glare around lights, especially at night
     
  • Worse vision than before SMILE, even with glasses or contacts