Thinking of having laser eye surgery? Here’s all you need to know

If you wear glasses, you are not alone.

About half of Australians wear eyeglasses or contact lenses.

Most Australians who wear glasses or contact lenses – around 30% – need them to see into the distance, a condition known as nearsightedness or nearsightedness. The remaining 20 percent need it to see up close.

You might think vision problems are a sign of aging, but nearsightedness disproportionately affects young people in their prime.

And the rate of people diagnosed with myopia is increasing. It is estimated that by 2050, half of the people in the world will need glasses to correct myopia.

Eyeglasses and contact lenses give your eyes the extra power they need, as long as you have regular check-ups to make sure the prescription is correct.

But some people find glasses bulky and restrictive, or just plain boring, so they opt for laser eye surgery.

Before you choose to walk – or trip – on this path, there are a few things you should know about your eyes and the procedure.

How your eye works

Your eye is like a camera. Just like you need to focus the light to take a good photo, you need to focus the light on the back of your eye, the retina, to see clearly.

Your ability to focus comes down to two structures: the cornea and the lens.

The cornea, at the very front of the eye, does most of the work. The lens, which sits behind the colored part of your eye, makes the final 20 to 30 percent.

Sometimes the alignment between your cornea, lens, and retina is not perfectly in sync.

Myopia occurs when the focusing power is too strong and light concentrates in front of the retina, making it difficult to see in the distance.

If the light is focused behind the retina – known as “hyperopia “or hyperopia – it will be more difficult to concentrate on things up close.

There is a third vision problem also called astigmatism, where your cornea is not perfectly round. It looks more like a rugby ball and the light is focused on different points of the retina.

Laser surgery simply shifts the prescription from your glasses to your cornea so that the light is sharply focused on the retina. But it’s most effective at times in your life when your eyesight is stable.

The shape and size of your eye changes rapidly until you are around 18 months old. Then it continues to change – albeit much more slowly – until you are around 20 years old.

From there, there is very little change until your mid-forties, when the lens in your eye becomes stiff and stops focusing precisely that it was used to – a condition known as presbyopia.

Things get a lot more complex the moment your goal stops working. There are a few alternatives to fix this problem, but there is no perfect solution.

What are the types of laser eye surgery?

There are three types of laser eye surgery.

• Surface treatment (photorefractive keratectomy or PRK) place your prescription directly on the front surface of your eye. The skin of the eye – the epithelium – is disturbed and takes a few days to heal. Your eye may be sore right away, but your vision is pretty good right away and will become perfect after a few weeks.
• LASIK (laser assisted in situ keratomileusis) uses two lasers. The first creates a shutter in the cornea, while the second places your prescription on the cornea below the shutter. Then the shutter is carefully repositioned. Although your eye may look a little grainy, you will have excellent vision in a day or two.
• The third option is SMILE (extraction of lenses by small incision). It uses the laser to cut a disc in the cornea that your surgeon removes through a small incision on the surface. Your eye will be a little rough, like with LASIK, but your vision will be good right away, although it may take a while to get good.

Laser surgery is not covered by Medicare and costs vary depending on the type of procedure.

What is the best procedure for me?

Evidence of high quality reviews shows that the three techniques give equally good vision at one year.

But each type has its own limitations, risks, and side effects – it’s surgery after all – so you need to talk to your doctor to determine which technique is best for you.

PRK causes more discomfort and generally takes longer to recover, but has lower rates of dry eye and is structurally stronger than the other two techniques.

LASIK makes dry eyes worse and if you haven’t had a chance to have an eye accident, it can dislodge the flap and potentially damage the eye. This is why it is not recommended if you play contact sports or if you are in the police or the military.

SMILE cannot treat hyperopia.

Regardless of the technique, you may need to have another surgery within 10 years if your eyes change or your eye unexpectedly heals.

Although you can repeat PRK or LASIK surgery, you can no longer use SMILE.

What does it do?

It is normal to feel anxious before having eye surgery.

But the procedure is fairly straightforward and usually only takes about 15 minutes in total for both eyes.

You are awake, but your eye is numb so you don’t feel anything.

Sometimes a special device is used to keep the eye open and still during surgery.

During the procedure, the laser makes loud noises and a peculiar smell – it’s not your eye that’s burning you – it’s just the way the laser works.

Since both eyes are treated on the same day, you will need someone to pick you up after the operation and you will not be able to drive for a few days.

Most people end up taking a week off, but if your eyes heal quickly, you can go back to work sooner.

Is Laser Surgery Right For Everyone?

No.

There are limits to what the laser can treat, and in some cases, for example if your cornea is too weak, you may not be suitable for a laser procedure.

But remember, if you are under 40, whether or not surgery is an option for you, eyeglasses and contact lenses, if used correctly, are just as good for improving your vision.

If you are over 40, your eyesight is complicated by other conditions and the treatment options are much more complex. Sometimes glasses are the best option, while in other cases laser surgery or lens surgery will be better, so you should talk to your doctor.

Dr Chameen Samarawickrama is a corneal surgeon and clinical associate professor at the Westmead Institute for Medical Research, University of Sydney; and Joint Lecturer at the University of New South Wales. He is one of the top 5 RN scientists for 2019.