Frequently asked questions – LASIK

What is LASIK?

LASIK is an established surgical procedure available here in Singapore to correct common vision problems including short-sightedness (myopia), long-sightedness (hyperopia) and astigmatism.

LASIK’s popularity since its introduction in the 1990s has resulted in it being synonymous with Laser Vision Correction (LVC) when in fact, LASIK is simply one of several type of LVC. Unless otherwise stated, LASIK is used interchangeably with Laser Vision Correction in this F.A.Q.

To read more about LASIK surgery, click here.

What is Laser Vision Correction?

Laser Vision Correction (LVC) or Laser Eye Surgery, is a type of Refractive Eye Surgery that is used to correct common vision problems such as myopia, hyperopia and astigmatism. There are 3 main types of LVC available in Singapore today:

ReLEx^® SMILE
LASIK
Advanced Surface Ablation (PRK, TransPRK, LASEK, Epi-LASIK)

What is Refractive Eye Surgery?

Refractive Eye Surgery is a kind of surgery that changes the refractive state of the eye in order to decrease or eliminate the need for prescription glasses and/or contact lenses.

In addition to Laser Vision Correction, Refractive Eye Surgery also includes Implantable Contact Lens and Refractive Lens Exchange (also known as Clear Lens Exchange).

What eye conditions does LASIK correct?

LASIK is recommended for correcting:

Myopia (short-sightedness) between 100 and 1,000 degrees
Hyperopia (long-sightedness) up to 350 degrees
Astigmatism up to 350 degrees

What is the minimum age for LASIK?

18 years of age. This is when your eye prescription is stable.

Can anyone get LASIK done?

LASIK is suitable for most people, however there are exceptions as listed below:

Below 18 years of age (if you are below 21 years old, you need parental consent)
Eye prescription that is well out of the degree ranges stated here
Eye prescription that has been unstable in the past 12 months
Eye conditions such as glaucoma and cataracts
In poor health
Pregnant or breastfeeding
Dry eye syndrome that is severe
On certain medications, example for acne treatment which may cause dry eye
Very thin, irregular shaped, or steep (keratoconus) cornea

How will I be evaluated for LASIK?

You need to have a pre-LASIK evaluation done to assess if you are suitable for LASIK. The process which consists of a number of eye tests, takes approximately 3 hours.

Among the tests included are:

Corneal shape and thickness
Intraocular pressure
Manifest refraction
Pupil dilation
Dry eye test

Note that after pupil dilation, your far vision will be unaffected, however, you may need to remove your glasses to see near. In addition, your sensitivity to bright lights will increase but this wears off after 4 to 6 hours. So, have your sunglasses with you.

The eye doctor (ophthalmologist) will share the results and discuss your options based on the condition of your eye, your occupation and lifestyle.

How do I prepare for the pre-LASIK evaluation?

To prepare for the evaluation, if you are a contact lens user, you need to:

Stop using soft contact lenses at least 3 days before the evaluation
Stop using hard contact lenses at least 14 days before the evaluation

What should I do on the day of the pre-LASIK evaluation?

There is no need to fast for the evaluation.
If you need to drive, bring along a pair of sunglasses as your eyes will be more sensitive to light after pupil dilation.
Some people may experience headache and nausea, which are uncommon

Can I get LASIK done if I have dry eye?

This will depend on the severity as well as the reversibility of the condition. The good news is that for most people, their condition is mild enough for LASIK to be done.

Do note that LASIK may aggravate the dryness but only temporarily; within 3 months, most people’s condition will revert to what it was before.

For a small number of patients, there may be increased dryness up to 6 months, while less than 1% of patients have increased dryness up to 12 months or more.

You are advised to have your dry eye syndrome diagnosed and treated before getting LASIK done. To ensure there is no relapse, stick to your treatment faithfully. Continue using your eyedrops as prescribed, even if you feel that you do not need them.

What is LASIK surgery?

LASIK (Laser-Assisted In Situ Keratomileusis) surgery is one of 3 types of Laser Vision Correction procedures (the other 2 being ReLEx SMILE and Advanced Surface Ablation). It is ideal for higher degrees of myopia, takes 30 minutes to perform for both eyes, has minimal discomfort and a quick recovery period. It has 3 main steps:

A corneal flap measuring 22mm in circumference is created on the corneal surface by a femtosecond laser and then folded back.
A second (excimer) laser then sculpts the corneal tissue to correct the refractive errors.
The flap is then repositioned where it will remain in place to allow the cornea to be fully healed.

Note:

Rare occurrence of flap dislodgement due to trauma.
Potential occurrence of Corneal Ectasia (see Collagen Cross-Linking).

What is Customised LASIK / Wavefront LASIK surgery?

This is a kind of LASIK where the excimer laser is guided by Wavefront technology to measure aberrations in the cornea’s shape and texture in 3 dimensions. After mapping the contours of the cornea, the laser will be customised to correct the refractive errors. Compared to standard LASIK, Custom LASIK or Wavefront LASIK surgery improves the ability of the eye to pick out fine details, increases the sensitivity to contrast, and results in fewer complications related to night vision, glares, and haloes.

What is ReLEx SMILE surgery?

ReLEx SMILE (Refractive Lenticule Extraction – SMall Incision Lenticule Extraction) is a Laser Vision Correction procedure that does not require a flap to be created; it is minimally invasive and has a rapid recovery period. It is suitable for individuals engaging in sports or working in occupations with some risk of head or eye trauma. It has 2 main steps:

A disc-shaped piece of corneal tissue called a lenticule is created just beneath the corneal surface by a laser.
A corneal incision measuring 4mm is then created by the same laser through which the lenticule is removed. The reshaped cornea now allows for corrected vision.

Note:

ReLEx SMILE is unable to correct long-sightedness (hyperopia) or pure astigmatism (absence of myopia).
Not suitable for very low levels of myopia
If an enhancement is required, it usually requires conversion to LASIK or PRK.

What Is Advanced Surface Ablation surgery?

Advanced Surface Ablation (ASA) is a group of Laser Vision Correction procedures that includes PRK, TransPRK, LASEK, and Epi-LASIK. They do not involve making a flap, nor an incision; they are surface–based, where the cornea is reshaped with a laser. ASA is suitable for thinner corneas, for those with active lifestyles as it minimises issues such as dry eye, corneal ectasia, and flap dislodgement. It has 3 main steps:

Removal of a thin layer of cells (epithelial cells) on the corneal surface.
Using an excimer laser to sculpt the corneal tissue to correct the refractive errors.
Protecting the eye with a ‘bandage contact lens’ to allow the surface cells to regrow over a few days.

Note:

Option of using Wavefront technology to guide the excimer laser
A longer recovery time of 5 to 7 days before your vision stabilises for normal activities.
On eye medication for several weeks up to a few months.

What Is PRK?

PRK (Photorefractive Keratectomy) is an Advanced Surface Ablation procedure where the epithelium (the thin layer of epithelial cells on the surface of the cornea) is removed via the application of alcohol. The epithelium is discarded after removal. What follows after this is the same for all ASA procedures; an excimer laser shapes the corneal tissue to correct the vision, and a bandage contact lens is used for cell recovery.

What Is TransPRK?

TransPRK (Transepithelial Photorefractive Keratectomy) is an Advanced Surface Ablation procedure that is akin to PRK. The only difference is that a laser is used to remove the epithelium instead of alcohol for TransPRK. All other features are the same as that of PRK; the epithelium is discarded, an excimer laser is used to sculpt the corneal tissue, and a bandage contact lens protects the eye while the cells regrow. There is no supporting clinical data to show that TransPRK improves the surgical outcome as compared to PRK.

What Is LASEK?

LASEK (Laser-Assisted Sub-Epithelial Keratectomy) is an Advanced Surface Ablation procedure that is similar to PRK where alcohol is used to ‘detach’ the epithelium. However, LASEK differs from both PRK and TransPRK in that instead of being discarded, the epithelium is left ‘hinged’ as a sheet that is pushed to one side. After the cornea has been sculpted with an excimer laser to correct the vision, the epithelium is replaced for it to naturally heal (under the protection of a bandage contact lens).

What Is Epi-LASIK?

Epi-LASIK (Epi-Laser-Assisted In Situ Keratomileusis) is an Advanced Surface Ablation procedure that involves the forming of an epithelial sheet by using an epikeratome (blunt blade), hinging the sheet to the side while corneal shaping with an excimer laser takes place, which is then followed by the sheet being replaced and covered by a bandage contact lens for the cornea to heal.

How does LASIK compare to ReLEx SMILE and ASA?

LASIK

Quick visual recovery
Less discomfort
Able for enhancements to be done earlier
Able to treat most eye prescriptions

ReLEx SMILE

Quick visual recovery
No risk of flap complications
Less incidence of dry eye
Suitable for active lifestyles
Lower risk of corneal ectasia
Risk of infection is lower due to the smaller 4mm incision

ASA

No risk of flap complications
Lower occurrence of dry eye
Suitable for active lifestyles
Recommended for thinner corneas

If you are deemed suitable for Laser Vision Correction based on your pre-LASIK evaluation results, your eye surgeon will discuss with you the most suitable procedure for your eye condition and lifestyle needs.

What are the risks of undergoing LASIK?

LASIK

Potential flap-related complications and dry eye
Rare complications such as corneal ectasia

ReLEx SMILE

Potential incomplete lenticule removal
Rare complications such as corneal ectasia

ASA

Longer recovery
Higher discomfort

What are the side effects of LASIK?

These are temporary; lasting several days/weeks:

Dry eye
Haloes
Glares
Mild vision fluctuation
Rare occurrence of flap complications and infections

Can LASIK be performed on 2 eyes at the same time?

Yes, today, most patients will opt to have the procedure done on 2 eyes at one go as the technology has matured. You may, however, stagger the procedure if you wish. In fact, patients had to do 1 eye at a time when LASIK was initially introduced to:

Minimise the risk of infection in both eyes.
Make adjustments in the procedure for the second eye based on outcomes for the first eye.

Do I need collagen cross-linking with LASIK?

Collagen Cross-Linking (CXL) is an add-on procedure that is done during the surgery to strengthen the cornea in order to:

Minimise the occurrence of Corneal Ectasia where the cornea is unable to retain its shape, leading to degraded vision.
Prolong the effects of the laser correction.
Minimise the need for an enhancement after the procedure.

The process:

Applying Vitamin B2 drops to the eye.
Shining UV light on the eye for about 1 minute to activate the collagen fibres in the eye to cross-link.

It is difficult to predict with certainty if CXL will prevent poor vision from returning. However, studies have shown that including CXL exhibits improved stability.

What do I need to do before the day of the LASIK surgery?

Likewise, when preparing for the pre-LASIK evaluation, stop wearing soft contact lenses at least 3 days before the surgery, and stop wearing hard contact lenses at least 14 days for hard lenses.

If you are having Collagen Cross-Linking done, do not take large amounts of Vitamin C 1 week before the surgery. However, eating small portions of fruits and vegetables is fine.

How long does LASIK surgery take?

Expect to be in the eye centre for about 2 hours. The procedure itself takes about 30 minutes for 2 eyes. The steps for each of the different Laser Vision Correction procedures is outlined in the earlier section in this F.A.Q.

What should I do on the day of the LASIK surgery?

Take a shower and do not apply any make-up, facial products or perfume as they may interfere with the performance of the laser.
Have a light meal; there is no need to fast.
Ask someone to accompany you if it makes you feel more comfortable.
Take a cab or be driven home – you should not be driving immediately after the surgery.
Bring a pair of sunglasses as your eyes will be more sensitive to light immediately after the surgery.
Arrive at the eye centre early so that you can settle in and relax yourself for the surgery.

Is LASIK surgery painful?

Most people do not feel much pain. There may be minor discomfort however, with some people feeling a slight pain or burning sensation when the effects of the anaesthetic eyedrops wear off. The doctor may prescribe painkillers as part of your medication.

What happens after LASIK surgery?

Expect blurry vision during the first 6 hours after the surgery.
You will be given eye shields to prevent accidental rubbing of your eyes while you sleep during the first week.
There will be medication instructions for you to follow strictly.

What is the recovery time for LASIK surgery?

Of the 3 procedures, LASIK and ReLEx SMILE have faster recovery times.

It will take about 3 days to achieve functional vision for LASIK and ReLEx SMILE; to be able to perform daily tasks and return to work. For ASA, it takes between 5 and 7 days.

For your vision to be stabilised (for LASIK, ReLEx SMILE and ASA), it takes about 3 months.

Do I need to return for follow-ups?

You will need to return for follow-up reviews after the surgery:

LASIK/ReLEx SMILE: 1 day, 1 week, 1 month and 6 months after the surgery.

ASA: 1 day, 3 days, 1 week and 1 month, 2 months, 3 months and 6 months after the surgery.

How many days of medical leave for LASIK surgery?

On average, 3 days for LASIK and ReLEx SMILE, and 5 to 7 days for ASA.

What do I need to avoid after LASIK surgery?

For optimal outcomes, follow these precautions after surgery:

24 hours: No driving or operating heavy machinery
3 days for LASIK/ReLEx SMILE and 1 week for ASA: Abstain from prolonged reading, working on the computer and watching television
1 week: Do not apply eye makeup
1 week: Do not go to smoky and dusty places
1 week: Prevent water from entering your eyes while washing your face and bathing
1 month: Avoid swimming, the jacuzzi, sauna, hot tubs and hot yoga
1 month: Do not engage in contact sports, and use a headband to prevent sweat from entering your eyes

What if there is under-correction or over-correction?

Over or under-correction of vision may occur in less than 2 to 5% of cases. If the prescription is +/-0.75 or more post-surgery, you may undergo an enhancement 3 months later or after your refractive error has stabilised provided it is safe and beneficial to do so.

Will LASIK last forever?

According to studies conducted, more than 95% of patients will continue to have good vision years after surgery. Some patients however (up to 6%) may require an enhancement within 10 years after the surgery.

Can I undergo cataract surgery after LASIK?

If there is an onset of cataract, you are still able to go for surgery to have it removed. However, you must note that the choice of intraocular lenses may be limited for a person who has had LASIK surgery previously. This could result in the patient needing to wear glasses after cataract surgery.

Am I able to wear contact lenses after LASIK?

You may wear cosmetic and coloured contact lenses 1 month after surgery. Due to the change in shape of your cornea or if there is dry eye, your old lenses may not fit as well. If so, you may get your optometrist to prescribe new lenses.

How much does LASIK surgery cost (in Singapore)?

As there are many variables involved, it is challenging to make comparisons between the costs at different eye centres and hospitals. That said, between a hospital and a private eye centre in Singapore, there is actually not much of a difference in cost.

Estimated rates for the different LVC procedures (for 2 eyes) are:

LASIK: $3,500 to $4,500
ReLEx SMILE: $5,300 to $6,000
Advanced Surface Ablation: $3,600 to $4,000

Differences in the packages can be due to the pre- and post-operative services provided, such as:

Eye evaluations
Reviews and enhancement

Study the packages carefully to avoid being saddled with hidden costs and unnecessary add-ons.

Can I use Medisave and insurance for LASIK surgery?

You are unable to use your Medisave for LASIK unless there is a difference of at least 300 degrees in power between your eyes AND if you are intolerant to prescription glasses and contact lenses.

For insurance policies, they generally do not cover LASIK procedures. However, there are some policies with higher premiums that will allow for it, while some companies may include it as part of their corporate benefits. Do check with your insurance providers if you are covered.

How do I know which doctor or eye centre is good?

Your choice of surgeon and eye centre should be based on:

Their ability to listen to what you need and give you unbiased advice
Pricing that is transparent and without hidden costs
Experience and credentials of the surgeon and clinic
How often patients require an enhancement after surgery
The laser technology and equipment used
How wide the spectrum of their treatment choices is to enable customisation for you
Their service quality

Make the choice that makes you feel the most comfortable. Your health and well-being are of utmost importance.