SMILE stands for Small Incision Lenticule Extraction. It is a form of laser vision correction which is minimally invasive and does not require the creation of a corneal flap. With SMILE surgery, a laser is used to shape a thin piece of corneal tissue (lenticule) within the layers of the cornea. This lenticule is then removed via a small incision.
Benefits of SMILE surgery include:
- Freedom from glasses and contact lenses
- No risk of flap related complications e.g. Flap dislocation, flap striae
- Quick recovery with minimal downtime (1-2 days)
- Minimal pain and discomfort during the recovery period
- Minimal disruption to work schedule
- Short period of post-SMILE surgery eye drops needed (typically 1 week)
- Fewer dry eye symptoms
A thorough assessment should be done before proceeding with any laser vision correction. In general, a suitable candidate for SMILE surgery includes patients who:
- More than 18 years old
- Healthy corneas
- Stable vision and refractive errors
- Keen to be free of glasses or contact lenses
- Keen to avoid the discomfort related to post PRK surgery recovery
- Keen for a laser vision correction procedure with minimal downtime
SMILE surgery is quick, taking about 10-15 minutes for both eyes. Recovery is generally comfortable with minimal discomfort. Antibiotic and steroid eye drops are given after SMILE surgery for about a week to prevent infection and minimise inflammation. Many patients are able to return back to normal activities in 1-2 days.
Risks of SMILE surgery include:
- Suction loss during surgery (may need to convert to LASIK)
- Glare and halos
- Dry eyes
- Vision fluctuation
- Under or over-correction
- Corneal ectasia
Recovery from SMILE surgery is quick with minimal downtime with many returning to work in 1-2 days. It is important not to rub your eyes during this early recovery period. A medical certificate is issued cover any absence from work after SMILE surgery.
During each follow up consultation after SMILE surgery, the recovery process is assessed and advise given on when returning to exercising is suitable. Most patients are able to return to running, jogging and gyming within a week. Swimming should be avoided during the early recovery period.
SMILE surgery itself is painless due to the numbing eye drops given before surgery begins. After SMILE surgery, there may be some discomfort immediately after the procedure, this largely resolves by the following day.
Significant improvement of vision is expected after SMILE surgery compared to the previous unaided vision without glasses or contact lenses. About 99% will no longer need glasses or contact lenses to meet legal requirements for driving.
During SMILE surgery, you will be given a target blinking green light to focus on. Focusing on this target light keeps your eyes perfectly aligned for the femto-second laser to accurately shape out the lenticule to be extracted. During the lenticule creation, this target green light will disappear about halfway through. You should continue to keep calm and keep your eyes straight as the laser completes the lenticule creation.
During SMILE surgery, the eye is held in position by a vacuum before the laser is applied. Gentle blinking during SMILE surgery is acceptable as long as there is no effort to tightly squeeze the eyelids closed.
After SMILE surgery, it is important to avoid eye rubbing and to keep the prescribed eye drops going as planned. Goggles are given and should be used at night to prevent eye rubbing during sleeping hours.
SMILE surgery is able to treat myopia (short-sightedness) and astigmatism.
SMILE surgery is not used to treat hyperopia (long-sightedness)
There is a role for SMILE surgery in treating presbyopia and achieving glasses freedom. This is in the form of monovision where one eye is corrected for distance vision and the other eye corrected for near vision. Patients may simulate this with a trial of contact lenses before undergoing SMILE surgery
During an assessment, a detailed history will be taken from you and specialised test to gather data on suitability will be done. This includes checking your visual acuity, refraction, cycloplegic refraction, corneal thickness, corneal topography, pupillometry, eye anterior segment examination, dilated fundus examination. Based on the assessment results, Dr Val Phua will then have a detailed discussion on the various options for laser vision correction and recommend a suitable treatment to meet your vision goals.
In some cases, mild residual refractive errors may be present after SMILE surgery or may come back with time. These residual errors can be corrected with the PRK or LASIK procedures.
In SMILE surgery, a laser is used to create a lenticule to be removed, reshaping the cornea and correcting any refractive error present. This correction is permanent. However as a person ages, there may be some changes to the eyeball that comes along with it. Some patients may find that the myopia or astigmatism “comes back” and may require an enhancement to re-correct this residual degree.