Q1: What is the difference between SMILE and LASIK?

LASIK laser eye procedure involves cutting a corneal flap, as the incision made on the cornea is larger than SMILE laser eye procedure,  LASIK patients may experience more dry eye than SMILE laser eye procedure because more corneal nerves are affected during the flap creation. In SMILE laser eye procedure, the incision made on the cornea is 80% smaller than the flap cut made during LASIK, minimizing the chances of dry eye and infection, thus a quicker recovery. As SMILE laser eye procedure is flapless, it is free from flap-related complications.

Q2: If laser vision correction is really as good as advertised, why do some ophthalmologists and optometrists still wear eyeglasses?

Ever met some ophthalmologists and optometrists and wondered why they are wearing glasses? In fact, many of them are actually having their eyes corrected through SMILE or LASIK. However, laser vision correction is not right for everyone. For people who have extremely high refractive errors, thin corneas, unstable prescription, dry eye syndrome, or taken prescription drugs… These conditions may disqualify them from undergoing the SMILE or LASIK procedure. So next time when you see some eye doctors or optometrists wearing glasses, it might just be that their specific conditions cannot be overcome with the laser vision procedures, or perhaps they just feel more comfortable in glasses. Remember, eye doctors are people too.

Q3: Who is not suitable for SMILE or LASIK?

The following people may not be suitable for SMILE or LASIK laser eye procedure:
- Eyes are not fully developed, with unstable prescription
- Thin corneas
- High prescription
- Keratoconus
- Cataract, glaucoma or other retinal disease
- Immune system disease, such as rheumatoid arthritis, systemic lupus erythematosus
- Are on medications that may affect wound healing, such as steroids
- Pregnancy or breastfeeding

Q4: Does SMILE or LASIK surgery hurt?

We use anesthetic eye drops, you will feel little heaviness in your eyes with very little or no pain sensation during SMILE or LASIK procedure. Patient may feel a sensation similar to the presence of a foreign object in the eye, with some amount of soreness, excessive tearing, discomfort towards strong lights after the SMILE or LASIK laser eye procedure.

Q5: How much time does SMILE or LASIK procedure take?

The actual SMILE laser eye procedure takes around 5-6 minutes per eye, and 10 minutes for LASIK. For preparation and post-surgery check-up, you should plan on staying at our centre for approximately 2 hours on your day of SMILE or LASIK procedure.

Q6: If I have had surgery for a detached retina before, is it possible to have SMILE or LASIK?

Yes, it is possible to have SMILE or LASIK laser corrective surgery after repair of a retinal detachment in select cases. Our recommendation is to be evaluated by an ophthalmologist first to ensure that the retina is healthy and then proceed with SMILE or LASIK laser eye procedure.

Q7: What defines a successful SMILE or LASIK procedure?

The procedure is successful if the patients have less dependence on, and maybe complete freedom from, glasses and contact lens. However, you may find that you still need the aid of your glasses or contact lens for some occasions, like reading or driving at night. Normally, your refractive errors (short-sightedness, long-sightedness and astigmatism) can be corrected to 1.0 dioptre or below. You can have less dependence on your visual aids within this range in your daily life.

Q8: Can you guarantee 1.0 vision after SMILE or LASIK procedure?

It’s important to have appropriate expectations, and understand that like most others procedure, laser eye procedure is not a miracle cure that guarantees perfect vision. However, both LASIK and SMILE laser eye surgeries boast a high satisfaction rate and the majority of patients can see clearly without glasses after the procedure.

Q9: Do I need to stop wearing contact lenses prior to the SMILE or LASIK procedure?

You should stop wearing contact lens before the comprehensive eye examination, and same before the SMILE or LASIK laser eye procedures. You can switch to glasses instead.

>Soft contact lens: 7 days
>Hard or gas permeable lenses: 3 weeks
>Ortho-K lens: 3 months

Q10: Compared to LASIK, SMILE is relatively new, is SMILE as safe as LASIK with sufficient clinical studies to support?

SMILE, using the VisuMax® femtosecond laser, has been around for more than 7 years. SMILE has received approval in Europe in 2011, it also obtained an approval from the FDA in 2016. SMILE has been shown to be safe and effective, both in FDA trials and in international studies. A clinical study of the safety and effectiveness of VisuMax to correct short-sightedness found the procedure resulted in stable vision correction at 6 months. 88% of patients had an uncorrected visual acuity of 1.0 or better.

Q11: What happens if I move my eyes during SMILE or LASIK? Will it affect the effect of vision correction?

No worries, after putting anesthetic eye drops in your eyes, the surgeon will then clamp your eyelids with a speculum to keep your eye open during the procedure. The patient can relax.

Q12: Can the eye examination and SMILE procedure be arranged on the same day?


Q13: Can both my eyes be operated on at the same time?

Yes. According to our statistics, more than 95% of our patients prefer to get both eyes done at the same time.

Q14: Can I eat or drink before and after my laser eye procedure?

There are generally no restrictions on eating before or after your laser eye procedure. We encourage our patients to eat before arriving for the procedure, so that you feel more comfortable and relaxed during SMILE or LASIK.

Q15: Will it be better to have SMILE or LASIK in the hospital?

Hospitalisation is not a must for SMILE or LASIK laser eye surgery. Many vision correction centers, including Hong Kong Laser Eye Centre & Hong Kong Eye Specialists Centre, are equipped with advanced surgical instruments, operating rooms and other supporting equipment with international standards. Compared with hospital wards, having the laser vision correction at clinics can have a lower chance of getting infectious disease transmission.

Q16: Can I still use contact lens or spectacles if the treatment does not give satisfactory results?

Yes, you can still wear contact lens or spectacles to improve vision if the treatment does not give satisfactory unaided vision. As the shape of the cornea has been changed by the laser surgery, it may not be possible to wear contact lenses in all cases. Please discuss with your ophthalmologist or optometrist on this.

Q17: Can I get other eye surgery after SMILE or LASIK?

Yes. SMILE or LASIK and other types of laser vision correction alter the curvature of the cornea, they do not affect other eye tissues (such as your natural lens inside the eye).

Q18: What are the risks of SMILE or LASIK?

SMILE and LASIK are low-risk procedures, the most common undesired outcomes are over-corrections or under-corrections, sometimes enhancements will be performed to retreat the issue. Other potential risks are flap-related complications, infection, glare, astigmatism, dry eyes, acute sensitivity to bright lights or night vision symptoms. To determine whether you are a candidate for SMILE or LASIK, our ophthalmologist will examine and get your eyes dilated, this comprehensive dilated eye examination will help check your cornea, your existing refraction, the inside of your eye like retina.

Q19: Do SMILE or LASIK cure the vision problems caused by severe myopia?

SMILE or LASIK and other types of laser vision correction only alter the curvature of the cornea, not the shape of the eyeball. The vision correction procedures will not be able to lower the risk of retinal detachment, cataract and glaucoma which caused by high myopia.

Q20: When can I workout after SMILE or LASIK?

Most patients can resume exercise after 1 week. Our ophthalmologists recommend avoiding swimming pools, water sports and hot tubs for 1 month after laser vision correction. Patients should be careful to avoid trauma to the eye after undergoing SMILE or LASIK, so sports eye protection is very important. Patients should avoid strenuous contact sports (basketball, football, boxing) for one month after SMILE and 3 months after LASIK.

Q21: When can I watch TV and use phone after SMILE or LASIK?

You can see right after SMILE or LASIK. However, you will experience some level of burning, tearing, light sensitivity after the laser vision correction. Watching television, reading, working on the computer can be resumed 24 hours after SMILE or LASIK procedure. You may want to sleep 3-4 hours after the laser vision correction.

Q22: When can I return to work after SMILE or LASIK?

Most patients return to work within one or two days following their SMILE or LASIK laser eye procedure. If your profession makes scheduling breaks more challenging, such as firefighters, policemen and flight attendants, please talk with our doctors about when to return to work.

Q23: When can I fly after SMILE or LASIK?

Most patients can fly 1-2 days after the laser eye surgery, depending on how quickly the vision stabilises. Your eyes may be more prone to drying out during flight because of the low humidity in the airplane cabins. Please talk with our doctors to see if you need to use lubricating drops more frequently to combat the dryness caused by air conditioning.

Q24: How long does it take for vision to stabilise after SMILE or LASIK? Do I need to wear glasses?

Most patients see clearly within 24 hours after SMILE or LASIK vision correction procedures. Full recovery varies by patient, it may take 1 to 3 months for your vision to fully stabilise after SMILE, and 3 to 6 months after LASIK procedure. Initially, your vision might fluctuate, this is perfectly normal and should improve gradually day by day. During this time, our ophthalmologists will meet with you regularly to check on your vision.

Since SMILE or LASIK procedure is typically performed to correct refractive errors rather than issues stemming from presbyopia, you should keep your reading glasses on hand after SMILE or LASIK. You may find you still need glasses or contact lenses for a few activities for specific tasks like night driving. Most patients do not need to wear glasses in daytime after SMILE or LASIK vision correction procedures.

Q25: Can I wear colored contact lens after SMILE or LASIK?

In most cases, Yes, contact lenses after SMILE or LASIK are safe. However, as SMILE or LASIK vision correction procedure alters the curvature of the cornea, the lens will fit poorly on your eyes and you may find it rather uncomfortable. Please talk with your eye surgeon for specific recommendation about this.

Q26: Can I wear perfume, makeup and eye makeup the day I get consultation and surgery?

You should not wear any eye makeup during the pre-op consultation; and you should not wear perfume/cologne, makeup and eye makeup on your surgery day. Makeup is a breeding ground for bacteria, while perfume is just like dust particles or water molecules which floats in the air. We do not want extra stuff on your face or in the air in order to minimise any risk of infection and irritation.

Q27: Does SMILE or LASIK cause or accelerate presbyopia?

No, SMILE or LASIK laser eye procedure does not cause or accelerate presbyopia. Presbyopia begins around the age of 40, the lens behind the cornea becomes harder and less flexible, making it more difficult for the eye to change shape to focus on close objects. SMILE or LASIK only reshapes the cornea, not the lens. SMILE or LASIK reduces the need for glasses, and it does not make presbyopia worse, or make it happen sooner.

Q28:Who should have SMILE Xtra, LASIK Xtra or Corneal collagen cross-linking treatment?

SMILE Xtra or LASIK Xtra is a corneal strengthening (cross-linking) procedure. It is suitable for patients with thin corneas following refractive surgery. It potentially reduces the risk of corneal ectasia in all patients.

Smile Xtra, Lasik Xtra or cross-linking procedure involves the use of riboflavin (a type of vitamin). Immediately after SMILE or LASIK, the riboflavin solution and ultraviolet light is applied to the cornea. As a corneal strengthening procedure, cross-linking has been widely performed for eyes with: Thin cornea, high myopia, weak cornea (which may have a high opportunity of regression), conical cornea (keratoconus), corneal degeneration.

Q29: Can I take shower, wash my hair or wash my eyes with tap water after SMILE or LASIK?

You may take showers and wash your hair the day after your SMILE or LASIK laser eye procedure. Patients must be extremely cautious to keep water, shampoo, and facial washing liquid away from your eyes for the first week after SMILE or LASIK. And please do not rub your eyes with a towel when you clean your face.

No matter you take SMILE or LASIK or not, you should not wash your eyes with tap water. Using tap water to wash your eyes can be either viral or bacterial (e.g. acanthamoeba).

These SMILE or LASIK aftercare precautions allow your corneal tissue to heal properly, otherwise you may: Run the risk of infection (with water, soap, shampoo), experience burning and irritation, wrinkle the corneal flap made during LASIK (if you rub your eyes), or accidentally exacerbate any dry eye symptoms.