What is LASIK?

Laser in-Situ Keratomileusis, or LASIK for short, is a safe and effective laser vision correction technique for myopia (shortsightedness), astigmatism and hyperopia (long sightedness). LASIK is safe, effective, and accurate, and it is currently the fastest growing ophthalmologic procedure in the world today.

Why LASIK?

Many people have chosen LASIK as a permanent change to correct their refractive errors as it has minimal and temporary side effects. There are no injections and no sutures involved, only numbing eye drops, making it a quick surgery. Recovery is also quite rapid, as most patients who undergo LASIK regain their vision quite quickly.

It must be noted, however, that LASIK cannot correct presbyopia, or age-related problems. This is because presbyopia is the result of muscle slackening, and LASIK does not improve the muscle tone in any way, but instead changes the curvature of the cornea.

Who qualifies for LASIK?

• People who are at least 18 years of age and have stable vision for at least a year
• People who encounter problems in using spectacles and contact lenses due to profession, activities, eye health, or environments which do not facilitate their use
• People who do not have corneal diseases or other eye diseases, such as significant retinal degeneration or severe dryness of the eye. You also should not have other complicating diseases which affect the healing process, such as SLE.
• Women who are not pregnant.

As a patient, you also should have a complete and detailed understanding of the advantages and disadvantages of LASIK surgery, as well as have realistic expectations of the outcomes.

LASIK explained

1. Preliminary eye examination

The initial examination of the eye will take 3 to 4 hours and normally includes:

• measurements of your pupil size
• topographic mappings of your corneas
• detailed wavefront measurements of the optics of your eyes
• measurement of your refractive error.

Some eye drops will be used during the examination, and these will make your vision slightly blurry for the next 4 to 6 hours. If you are a contact lens wearer, you should stop wearing your soft contact lenses at least 3 days before the examination, in order to allow the cornea to resume its natural shape. Hard or semi-hard contact lens wearers should stop wearing their lenses at least 7 days in advance.

2. LASIK Surgery

Before beginning the surgery, you will be given a series of eye drops to numb your corneal surface. LASIK utilizes the microkeratome to create a thin corneal ‘flap' which exposes the corneal bed. The ‘cold' excimer laser, which is highly accurate, is then used to reshape the cornea to correct refractive errors before the flap is replaced. The surgery is painless and will take only 15-20 minutes to complete.

After the surgery, you may experience symptoms of tearing or other forms of slight discomfort, which is normal. Your vision will be hazy initially but should improve after 3 to 4 hours, which is when healing starts to take place. Taking a nap will help to maximize the healing process, and your symptoms will improve dramatically after your nap.

As this is an outpatient procedure, you can return home immediately after the surgery.

3. Post-operative examination

After your surgery your doctor will follow up with you to check and ensure that everything is fine. You should have good usable vision from now on but quality of vision can fluctuate for up to a month.

With a procedure as simple as LASIK, you can now enjoy recreational activities, especially water and contact sports, without being limited by corrective lenses. Besides convenience, LASIK also helps to eliminate risks associated with long term contact lenses usage, as well as provide the boost in appearance and self-confidence that you need in life.

Editor's Qs

Is it suitable for people in their 40s and 50s who are getting presbyopic?

LASIK is suitable for all patients aged above 21, or once they have stable eyesight. For correction of myopia, there is strictly no upper limit with regards to age. However, people after the ages of 40 would have a higher chance of presbypia, an age-related disease causing difficulties with near vision activities like reading.

There is a specific technique called Monovision, which involves using LASIK to correct myopia fully in the dominant eye while leaving a slight myopia in the other. After the procedure, the patient will be able to read without visual aid for short periods of up to one hour as well as to see at a distance with only a slight deterioration. This is very suitable for people who want to lead a totally spectacle-free life.

Not everyone is suitable for Monovision. About 15 percent cannot tolerate the resulting condition and would need correction. To avoid this from happening, we put potential patients through a trial of contact lenses to simulate the condition. Only when they are fully comfortable will we allow them to proceed with Monovision.

What happens to the young who later develop cataracts after they've had LASIK done some years earlier?

LASIK is a superficial procedure which corrects the optical error by altering the thickness of the cornea using an accurately applied laser beam. As it does not go beyond the corneal surface, it does not affect any eventual eye disease that the person would have otherwise developed later in life, such as cataracts. In the event that cataracts do occur, the routine cataract surgery can be employed.

What if a patient is not satisfied after corrective LASIK?

Different people heal differently, the same applies to the LASIK procedure. When the corneal surface does not react in an expected way, the LASIK patient will find that an enhancement procedure is required to attain a satisfactory vision.

Enhancement LASIK surgery is usually performed only after six months, when the patient is deemed to have reached a steady state post-LASIK. The procedure is similar to the original LASIK, with the exception of the necessity of re-cutting the flap in most cases.

Some doctors seem to prefer doing one eye at a time, whereas others (especially abroad) will do both at once. Why?

The main obvious advantage of doing both eyes at the same time is the convenience to the patient. This includes less time needed off work for surgery and no inconvenient and uncomfortable spell of unbalanced vision.

There has been suggestion that performing LASIK one eye at a time gives a more accurate result. To date, scientific studies have shown that theoretical refractive advantages of one-eye surgery does not have a bearing on real life clinical practice.

Is it safer to do the eyes separately? The concern is that a complication, which is not apparent at the time of surgery can occur in both eyes hours or days later. Fortunately, the risk of this happening is remote. Moreover, most LASIK-related infections and inflammations are easily treatable with eyedrops.

Will someone who has LASIK at 20, and whose eyesight deteriorates further by 35, have to be re-LASIK-ed?

After puberty, most people do not experience a deterioration in far vision. If the worsening of eyesight is sudden, checks with an ophthalmologist would be required to rule out organic eye disease. If no apparent cause is found, and the patient remains suitable for LASIK, the procedure can be repeated again with no added risks.