10 questions to consider before going for LASIK

For people with nearsightedness (myopia), farsightedness (hyperopia) or astigmatism, LASIK surgery could be the key to a life free of cumbersome spectacles or contact lenses. But not everybody is a suitable candidate for this type of laser eye surgery. Here are the 10 main questions a LASIK surgeon is likely to ask you during a consultation.

1. How old are you?

If you're under 21, the LASIK surgeon will ask you to wait, just to make sure your vision is stabilised. If you're in your early 40s, you need to be aware that you might still need reading glasses later on. If you're in your 60s, you will need to be assessed for pre-existing cataracts. If you have them, cataract surgery might actually solve your vision problem, in addition to correcting any myopia, hyperopia, astigmatism or presbyopia that you might have, says Dr Mohamad Rosman Bin Othman, consultant for refractive surgery service at the Singapore National Eye Centre (SNEC).

2. How stable is your vision prior to LASIK?

No matter your age, it's important for your eyesight to have stabilised for at least a year before you have laser surgery.

3. What is your current eye prescription?

In terms of refraction (i.e. spectacle degree), the main limitation to LASIK is the patient's cornea thickness. This means that even patients who have high myopia or astigmatism can undergo LASIK as long as their cornea is sufficiently thick.

However, it is generally accepted that the results for LASIK in patients with very high refractive error, i.e. myopia of more than 1000 degrees, hyperopia of more than 400 degrees and astigmatism of more than 400 degrees, are less predictable and less satisfactory, says Rosman.

Related Q&A on Health Xchange: Our specialist answers LASIK questions

4. Do you have any eye disease?

There are quite a few eye conditions that need to be screened before LASIK surgery. Your doctor will check if you suffer, among other things, from ocular herpes, diabetic retinopathy, retinal detachment, dry eye syndrome or keratoconus, a progressive thinning of the cornea.

5. Do you have any medical condition?

Autoimmune diseases, such as rheumatoid arthritis, lupus or multiple sclerosis, are generally considered a contraindication for LASIK, as they might prompt an unexpected response to the laser surgery. Other conditions such as type 2 diabetes do not necessarily mean the surgeon will turn you away. However, they need to be well controlled to ensure a favourable healing situation.

Similarly, some drugs like Accutane or steroids may compromise post-op recovery. Tell your doctor about any and all medications you're taking.

Related article: Will the new ReLEX procedure eventually replace LASIK?

6. Are you pregnant or nursing?

Pregnant and nursing women undergo hormonal changes which can cause fluctuations in the vision. It is advisable that they wait at least 6 months after pregnancy or breastfeeding, whichever is later, before undergoing LASIK, says Dr Rosman.

7. What is the size of your pupils under dim lights?

Having very large pupils can increase your risk of night-time visual disturbances, such as starbursts or halos after LASIK surgery. The decision to operate is made on a case-by-case basis.

8. What is your current or intended line of work?

Most jobs do not prohibit refractive surgeries or LASIK. However, the Singapore Air Force (SAF) does not take in pilots, naval divers, submariners or some commandos who have undergone LASIK. Other types of refractive surgeries like PRK or EPILASIK are allowed. It is best that you check with the SAF about their requirements before undergoing surgery, recommends Dr Rosman.

According to their job ad for cadet pilots, SIA will not reject candidates who have undergone LASIK, but requires that their pre-surgical visual acuity meet the following criteria: myopia of not more than 500 degrees and astigmatism of not more than 125 degrees.

9. What are your favourite sports and hobbies?

If you regularly practise contact sports, martial arts or other activities which can put you at high risk of eye injury, you may not suitable for LASIK surgery.

10. Do you understand the risks of laser surgery and have realistic expectations?

As with any surgery, there are a number of risks involved. For instance, you could develop permanent dry eyes after LASIK. This is especially true if you're of Asian descent. Also, your vision might not be perfect after a first laser surgery, and you might require a second operation to achieve optimal results. Your surgeon will need to ascertain that you understand and accept these risks.

"Overall, about 10 per cent of people who consult for LASIK are turned away because they're unsuitable candidates," says Rosman. Should that be your case, know that the situation might be temporary and that oftentimes, alternatives could be considered, such as PRK (photorefractive keratectomy), implantable contact lenses or EPILASIK (epikeratome laser-assisted keratomileusis).

This article was written by the Health Xchange editor, with expert input from the Refractive Surgery Service at Singapore National Eye Centre.

On Saturday, 12 November 2011, invite your parents to attend this year's SingHealth Silver Years Forum and learn more on seniors' health topics such as dementia and chronic pain.

Health Xchange's articles are meant for informational purposes only and cannot replace professional surgical, medical or health advice, examination, diagnosis, or treatment.