1. I have high myopia and would like to undergo surgery to correct my shortsightedness. What types of surgery should I consider? What are the risks and complications?

High myopia is usually defined as myopia of -6.0D / -600 degrees and above. Recent medical advances have made it possible to permanently correct high myopia through laser surgery. Depending on the severity of your high myopia, LASIK surgery may be the procedure of choice. The main limiting factor to LASIK surgery is your corneal thickness. A thorough assessment of your eye is necessary before LASIK surgery can be attempted.

If your cornea is thick enough and your myopia is -6.0D / -600 degrees to -10.0D / -1000 degrees, WaveFront LASIK surgery may give quite accurate results. However, if you have very high myopia of -15.0D / -1500 degrees and above, other possible alternatives include clear lens extraction with intraocular lens implantation and phakic intraocular lens implantation. It is best to discuss each option in detail with your eye surgeon.

For LASIK surgery, the risks and complications are discussed in detail here. The complications of LASIK surgery are summarized as follows:
• Dry eyes
• Glares, haloes and starbursts
• Under or over correction
• Corneal flap complications
• Loss of best corrected visual acuity
• Contact lens wear intolerance
• Equipment malfunction
• Eye infection
• Glaucoma
• Retinal detachment


2. What is the success rate of myopia LASIK surgery?
The goal of LASIK surgery is to reduce or eliminate dependence on spectacles or contact lenses by the surgical reduction of myopia. In some cases, especially in patients above 40 years old, the eye surgeon may deliberately aim for slight under-correction. Over-correction with resultant farsightedness in patients above 40 years old is often not well tolerated due to difficulty in reading.

Current results show that for patients less than -5.0D / -500 degrees of myopia, the surgical results are extremely good with 98% achieving 6/12 vision after surgery without any optical correction. This usually translates into -1.0D / -100 degrees of myopia or less.

For patients between -5.0D / -500 degrees to -10.0D / -1000 degrees, the surgical results is about 92% achieving 6/12 vision after surgery without any optical correction.

3. How do I know if I am suitable for LASIK surgery?
It is generally agreed that the minimum age for patients going for LASIK should be at least 18 years old. There should be no significant change in the spectacles or contact lens prescription for the last two years. There should be no medical history of active eye diseases such as cataract, glaucoma, retinal detachment or keratoconus. Certain systemic eye diseases such as rheumatoid arthritis, polyarteritis nodosa, Wegener’s granulomatosis and other collagen vascular diseases which may cause corneal problems are also another contraindication to LASIK surgery.
Is LASIK surgery safe?

LASIK surgery is an established surgical procedure with millions of cases done worldwide. The first LASIK surgery was performed in 1989 and research so far has proven that the surgical results are stable and the surgery is safe.
LASIK surgery is considered by eye surgeons around the world as the overall procedure of choice for permanent surgical correction of myopia less than -10.0D / -1000 degrees. Safety, efficacy and stability of results are the main reasons why eye surgeons chose this procedure over the rest.

4. How long does the LASIK surgery take?
LASIK surgery takes only about 10 minutes or less per eye. The actual amount of time the laser is actively used on the eye is usually a minute or so.

5. What is the risk of blindness with LASIK surgery?
The risk of going blind after LASIK surgery is very rare. The reported risk of developing infection after LASIK surgery is about one in 5,000 surgeries. Even though an infection is potentially blinding, with early detection and treatment with the latest antibiotic eyedrops, most of these cases will not go totally blind but may lose some degree of visual acuity due to corneal scarring.

6. Is LASIK surgery painful? Do I need someone to escort me and bring me home?
The LASIK surgery is painless. The entire procedure is performed under anesthetic eyedrops which numb the eye. No injections are necessary. There will be some discomfort of the eyelids when a special instrument for keeping the eyelids open is inserted (called the lid speculum). Sometimes, the eye surgeon may prescribe a mild sedative to calm the patients down before the surgery.

It is best if someone can escort you home after the surgery. If this is not possible, it is important to reach home as soon as possible because the eyedrop anesthesia starts to wear off about 30-45 minutes after the surgery. There will be some irritation, tearing and light sensitivity in the operated eye once the anesthesia wears off.
These effects will usually last for about 8-10 hours after the surgery. It is best to sleep as soon as possible after the surgery – it will relieve most of the discomfort when the eyes are totally closed. Another option is to instill the lubricating eyedrops provided after the surgery and to wear sunglasses immediately after the surgery.

7. How is the LASIK surgery performed?
The patient lies down on a surgical bed or reclining chair underneath the laser machine. The eye surgeon will then clean the area around the operated eye and cover that area with a sterile surgical drape. Anesthetic eyedrops are applied and a lid speculum is inserted to keep the eyelids open. This part of the procedure where the eyelids are forced open by the speculum is the most uncomfortable part of the surgery.

An instrument is used to mark the cornea surface and the actual LASIK surgery can now start. A suction ring is applied to the eye to hold the eye firmly while the microkeratome moves across the eye to create the corneal flap. Suction is applied to hold the eye steady and to maintain the eye pressure while the flap is being cut by the microkeratome.

During this stage, the vision will dim or become dark due to the high eye pressure created by the suction ring – please do not be alarmed. There will be a high pitched mechanical whirring sound for about 10 seconds as the microkeratome moves across the eye. Suction will be released after this and the vision will return to normal.
The corneal flap is lifted up by the eye surgeon to expose the underlying corneal bed for the laser treatment phase. During the laser treatment phase, it is important that you keep looking at the blinking red light – the blinking red light may appear as a hazy red cloud but try to look at the center of the red cloud. The Excimer laser is started by the eye surgeon d a high pitch crackling sound of the laser is guided by information from the computer program which is keyed in by the surgeon. For myopia correction, the laser will reshape the cornea into a flatter curvature. For hyperopia correction (correction of farsightedness), the laser will reshape the cornea into a steeper curvature. This part of the surgery takes about 45-80 seconds.

Once the laser stage is completed, the corneal flap is unfolded back to its natural position and smoothed over the cornea. After a short period of about 1-2 minutes, the eye surgeon will recheck the position of the flap and the flap will adhere firmly to the cornea without the need for stitches.

8. What happens if I try to blink or move my eyes during the LASIK surgery? Will I go blind if that happens?
It is not possible for you to blink during the surgery as there is the lid speculum which keeps the eyelids open. It is also not possible for you to move your eye when the suction ring is applied to your eyeball – the suction force holds your eye firmly while the microkeratome cuts the corneal flap.

However, it is possible for you to move your eye during the laser phase. It is important for you to keep your gaze fixed on the blinking red light throughout the actual laser treatment. Do not worry too much that your eye may inadvertently drift away – the eye surgeon is monitoring your eye closely during the entire procedure and can stop treatment at any time if the eye starts to drift.

In addition, all modern lasers come equipped with a very sophisticated eye tracking system that actively follows every small eye movement. This will ensure that the laser treatment will be applied at the right location during the procedure even if there is a slight movement of your eyeball.

9. What is there is a power failure during the surgery?
All modern LASIK systems come equipped with a Uninterrupted Power Supply (UPS) for at least two hours. This is more than enough for a procedure that takes only 10 minutes.

10. Is there a need for stitches during LASIK surgery?
No stitching is required during LASIK surgery. The corneal flap adheres by surface tension within a few minutes and the surface epithelial layer will migrate inwards to seal the edges of the flap within 24 hours.

11. Can I rub my eyes after LASIK surgery?
Eye surgeons normally recommend that you avoid rubbing the eyes after LASIK surgery for the first three weeks. This is to prevent abnormal folds from developing in a corneal flap which may occur after vigorous rubbing.

12. What precautions must I take after the LASIK surgery?
There are several precautions that are important after LASIK surgery:
Please adhere to the antibiotic and steroid eyedrops regime as prescribed after the LASIK surgery – this is to prevent bacteria infection and to control the healing response.
• Avoid crowded and dusty places for the first three days after surgery
• A protective eye shield should be worn when sleeping for the first week after the surgery to prevent accidental rubbing and trauma to the corneal flap
• Do not squeeze your eyes too hard for the first day after the surgery
• Do not rub your eyes for the first three weeks after the LASIK surgery
• Do not drive for the first 24hours after the LASIK surgery

13. Can I see immediately after the surgery? How soon can I see well?
You can see immediately after the surgery, although vision will be a little blur for the first 12 hours. The most dramatic improvement in vision is noticed after resting the eye overnight. Most patients can see well enough to drive without glasses the day after LASIK surgery. A gradual improvement in vision is expected as further healing occurs over the next few weeks. Vision is usually stable in a month’s time. Some patients may complain of glare and haloes during the first few weeks after LASIK surgery. Those with large pupils at night or high myopia are more likely to be affected. Most of the time, these complaints will lessen or go away after six months.

14. How much medical leave must I take? When can I resume normal activities such as exercise?
Most patients can return to work the day after LASIK surgery. However, for the first one month after surgery, there may be some difficulty with reading small print. If this happens, please inform your ophthalmologist who may temporarily prescribe a pair of reading glasses for you. You should avoid crowded and dusty places for the first week after LASIK surgery to reduce the risk of bacterial infection. Swimming should be stopped for at least two weeks.

15. How much myopia is safe to be treated with LASIK surgery?
LASIK gives good results for myopia from -2.0D to -10.0D. A power of -15.0D / -1500 degrees is usually taken as the upper limit of safe LASIK treatment but this constantly changes as new software and technology develop. It is important to realize that the higher the amount of myopia treated, the greater the amount of corneal tissue that must be removed by the laser, and this will thin the cornea to the minimum safety limits.

Current treatment guidelines require the cornea to be at least 250?m thick underneath the corneal flap after LASIK treatment. This is one of the main limiting factors that determine the safe limits of myopia correction and the eye surgeon will measure the corneal thickness before LASIK surgery to determine how much myopia can be safely treated without compromising the minimum corneal thickness.

16. Can LASIK surgery treat astigmatism? What about long-sightedness?
LASIK surgery can treat astigmatism. With WaveFront laser technology, customized laser ablation with iris scanning technology improves the results of astigmatism correction and up to 4.0D of astigmatism can be treated relatively accurately. However, it is important to exclude keratoconus, a corneal disease characterized by high astigmatism and localized thinning of the cornea.

LASIK surgery can effectively treat up to +4.0D / +400 degrees of long sightedness. Long sightedness or hyperopia is the exact opposite of myopia, where the image falls behind the retina – it is caused by shorter than normal eyeball length or flatter than normal corneal curvature.

However, a lot of confusion exists about middle aged long sightedness (called presbyopia) – this is very different from normal long sightedness as presbyopia afflicts those usually around 40 years old d above. It is due to the reduced ability of the eye to focus near objects as a person ages. LASIK will not treat presbyopia directly – there are options such as monovision where one eye is deliberately left about -1.0D / -100 degrees myopic so that the patient can still read without glasses.
Another exciting development for the treatment of presbyopia is the use of multiconcentric zone laser ablations where special laser programs are used to shape the cornea so that the patient can see both far and near objects well – this is still being assessed and may come into widespread acceptance.

17. Can my vision be worse after LASIK surgery?
This is possible after LASIK surgery. It is known as loss of best corrected visual acuity and it means that the patient is not able to see as well after surgery as compared to before surgery, even with the best spectacles or contact lens correction. The most common causes for loss of best corrected vision are cornea related problems such as corneal haze or scarring, decentered or uneven laser ablation and corneal flap complications. Fortunately, with the latest advances in technology and improvements in techniques, the likelihood of this is reduced to less than 1%.

There is also a possible decrease in contrast sensitivity, which means that even though the patient has 6/6 vision, there is a reduced ability to discriminate between shades of grey, especially under dim lighting. This may cause objects to appear fuzzy or grayish. There may also be complaints of excessive light sensitivity, glare, haloes or ghosting. Haloes are ‘rings’ around lights. Ghosting is the phenomenon of seeing a second false image next to the real one. Most of these visual complaints will decrease with time but in some cases, they may persist indefinitely and affect the overall quality of vision.

18. Can I get better than 6/6 vision (eagle vision)?
Occasionally, some patients may get better than 6/6 vision. This may occur especially in WaveFront LASIK surgery and for the correction of low-moderate myopia. Recent studies have reported that for low-moderate myopia (-5.0D / -500 degrees or less), about 70% achieve 6/6 or better vision. However, for high myopia, the results are not as good, with only about 40% achieving 6/6 or better vision.

19. Are the results permanent or will my vision continue to deteriorate?
Yes, the results are permanent. Millions of cases have been done worldwide and research studies on the success rates have shown the results are stable as long as established treatment protocols are followed.

Another important factor is the stability of the refraction before LASIK surgery – if the patient had a stable refraction for at least two years before LASIK surgery, it is also highly likely that the refractive results would be stable. If the patient has a continuously increasing myopia before LASIK surgery, then it is highly likely that the myopia will continue to increase despite a good initial LASIK surgery result.

Unstable results have also occurred when the amount of corneal tissue exceeded treatment guidelines. Occasionally, unstable results have occurred because of treatment of eyes with undiagnosed keratoconus. Keratoconus is a disease characterized by progressive cone shaped thinning of the cornea. Its presentation may be subtle in the early stages and can only be diagnosed with specialized instruments.

20. I am now 40 years old and need reading glasses for near. After LASIK surgery, will I still need to wear reading glasses? What is ‘monovision’ correction?
The human eye starts to lose its power of focusing for near objects at about 40 years old. This aging phenomenon is called presbyopia or middle aged long sightedness. It is caused by the progressive hardening of the crystalline lens in the eye and weakening of the focusing ciliary muscles.

After successful LASIK surgery, if the eye surgeon corrected both eyes perfectly for distance vision, it is highly likely that you will need to wear reading glasses for near.
However, if the eye surgeon chose ‘monovision’ correction for you, then one eye would be left shortsighted and this eye would be suitable for near vision. The other eye would then be used only for distance vision. This is the advantage of ‘monovision’ correction and you do not need to wear reading glasses.

21. My daughter is keen for LASIK surgery but she is only 15 years old. What is the most suitable age for LASIK surgery?
Your daughter is considered too young for LASIK surgery. Most eye surgeons recommend that LASIK surgery be performed only for patients that are 18 years old and above. It is also important that the patients have stable myopia for at least two years. Below 18 years old, myopia is frequently unstable and the eye may heal with excessive scarring. However, in selected cases of severe anisometropia (large difference in refractive power between both eyes), if contact lens do not work, the eye surgeon may choose to offer LASIK surgery to these teenagers who are below 18 years of age.

22. I am keen for LASIK surgery but the technology keeps on improving. Should I wait for a few years more?
Presently, the technology is excellent and the surgical results are very good for low-moderate myopia. Most of the present research is focused on improving the LASIK results for patients with very high myopia (-10.0D / -1000 degrees and above) and those with high astigmatism (3.0D / 300 degrees and above). There is also research that is focused on LASIK surgery for patients with thin corneas as such patients are usually not suitable for LASIK surgery presently. It is best to go for a thorough eye assessment by an eye surgeon and discuss the pros / cons of LASIK surgery if you are keen.

23. How much does the LASIK surgery cost?
In the government restructured hospitals, LASIK surgery costs about $2,100-$2,300 per eye. In private practice, LASIK surgery costs about $1,900-$2,600 per eye. These are only surgical fees. The assessment fees (including consultation) are charged separately and are usually about $200-$280 for both government hospitals and private eye surgeons. It is best to discuss the charges separately with your eye surgeon. For a detailed listing of our LASIK pricing, click here.

Medisave unfortunately cannot be used presently except in cases where the patient suffers from very severe myopia (over -10.0D / -1000 degrees) or imbalanced vision of more than 300 degrees between the two eyes. In such selected cases, you can use your Medisave to pay up to $1,200 of the surgery cost.

24. If I want to have LASIK surgery, what happens when I see the eye surgeon?
If you are wearing hard contact lenses (RGP lenses), you will need to stop wearing them for at least 10 days before the consultation. If you are wearing soft contact lenses, you will need to stop them at least 3-4 days before the consultation. Please bring along a pair of sunglasses for the consultation as the eyes will be light sensitive and the vision slightly blurred after the dilated pupil examination during the pre-LASIK eye examination.

The pre-LASIK eye examination will include the following:
·• vision testing to check the visual acuity
·• testing of the eye power (objective refraction)
·• subjective refraction to fine-tune the objective refraction
·• eye pressure checks for glaucoma (tonometry)
·• detailed examination of the front part of the eye using a special instrument called a slit lamp biomicroscope, with special attention to the cornea dilated pupil examination of the eye, with special attention to the clarity of the crystalline lens and excluding any retinal problems (such as retinal tears/retinal detachments)
·• computerized testing of the eye power following the dilated pupil examination as this will detect any false myopia component (pseudomyopia)
measurement of the corneal thickness (pachymetry) to determine suitability for LASIK surgery
·• computerized mapping of the corneal surface to screen for irregular astigmatism and keratoconus

After performing all the above procedures, the eye surgeon will examine all the results and counsel you on your suitability for LASIK surgery, with an explanation of the risks and benefits of surgery. You should take this time to discuss with your eye surgeon any concerns that you may have regarding the LASIK surgery.

25. Why do most eye surgeons who are myopic not undergo LASIK surgery?
There are several myopic eye surgeons who have undergone LASIK surgery. Most eye surgeons who perform LASIK surgery consider it to be a form of cosmetic surgery – LASIK surgery is not performed to heal sigh threatening eye diseases and myopic patients who choose not to have LASIK surgery do not suffer from any loss of vision or deterioration in the quality of life. Hence, any patient who considers LASIK surgery must be properly counseled as to the risks and benefits of such surgery before proceeding.

26. What are the future advances for LASIK surgery?
The future advances of LASIK surgery focus on two aspects:
·• the accuracy of LASIK surgery
·• the safety of LASIK surgery

Presently, LASIK surgery is still the preferred technique for the treatment of low-moderate myopia and high myopia of not more than -10.0D / -1000 degrees. However, LASIK surgery does have its drawbacks:
·• the risk of infection due to the need to cut a flap in the cornea, resulting in a possible site for infection
·• the rate of healing among different individuals results in variable refractive results
the thickness of the cornea is a limiting factor
·• slight eye movements during the laser result in imperfect laser ablation

To reduce the risk of infection and to minimize mechanical failure during the cutting of the flap, research is now directed to new methods to ablate corneal tissue precisely without cutting a flap. New lasers such as the pico-YAG laser have been developed to vaporize corneal tissue precisely to achieve the desired refraction.

Another new technology developed is the use of high pressure extremely fine water jets to cut a corneal flap. This will result in a very smooth corneal flap. However, technology is still in the developmental stage.

The different rates of healing among individuals also result in slightly variable refractive results. Eye surgeons tend to overcorrect young individuals due to myopic regression – myopic regression is the phenomenon where the operated eye tends to become more shortsighted due to the vigorous healing response. Young individuals tend to heal more aggressively, with a faster myopic regression than older individuals. Traditionally, eye surgeons have always used steroid eyedrops to control the healing response. However, steroid eyedrops may cause glaucoma with prolonged usage. Other eyedrops such as cyclosporine eyedrops can be used to control the healing response – however, they too possess toxic side effects and are rather expensive. Research is ongoing to discover new types of eyedrops which can modulate the healing response with minimal side effects.

The thickness of the cornea has always been a limiting factor for LASIK surgery. If the cornea is too thin, even if the refractive error is low, LASIK surgery may not be safe. There should be a minimum thickness of the corneal bed (250?m or 0.25mm) after the corneal flap is cut – this is to ensure long term stability of the shape of the cornea. If the cornea is very thick, even if the refractive error is high, LASIK surgery can still be performed safely. Recently, many of the latest machines possess new software which allows minimal laser ablation of the cornea for a desired refractive result. For the same corneal thickness, this will allow higher refractive errors to be safely treated.

Slight eye movements during the laser ablation of the cornea have always been a problem. There are eye tracking devices using infrared technology that monitor the movement of the pupils and iris details – whenever the eye moves, the information is fed back to the computer that controls the laser. The laser will also move in several dimensions – vertically, horizontally and rotatory. With the latest iris scanning technology, rotatory movements are also detected – this improves the refractive results of LASIK surgery especially for patients with high astigmatism.