The new laser surgery that’s a real eye-opener
Laser surgery has helped more than a million people in Britain to throw away their glasses since its introduction two decades ago.
New developments mean many more could be tempted to try it, including thousands who suffer with presbyopia, age-related sight loss.
Laser treatment generally involves reshaping the cornea — the clear, spherical tissue on the front of the eyeball. Light passes through this and on to the retina at the back of the eye, where the image is interpreted. With short-sightedness, the cornea is too steeply curved, or the eyeball itself too long, meaning light falls short of the retina. Lasers can treat the problem by flattening the cornea.
I can see clearly now: New developments in laser surgery mean many more could be tempted to try it
They can also help people with long-sightedness, where the cornea is too flat, by steepening it. And used to treat astigmatism, where the cornea is oval, by making it into a rounder shape.
The most popular technique in the UK is Laser In Situ Keratomileusis (LASIK). Costing around 1,000 per eye, this involves cutting a flap from the top of the cornea, then lasering off thin layers of it to alter its shape. The process takes less than a minute, correcting moderate sight imperfections almost instantly.
But around 5 per cent of people suffer side-effects such as dry eyes, often because the nerves that stimulate production of tears are damaged.
Another side-effect is halos — rings of light that can appear at night if the treatment is not customised correctly for the cornea.
However, newer techniques may avoid these setbacks. It’s also now possible to use lasers to treat presbyopia, where the lens of the eye slowly stiffens, affecting near vision.
Here, we outline some of the latest laser techniques that could help you, and Professor David Gartry, consultant ophthalmic surgeon at Moorfields Eye Hospital, London, explains their pros and cons?.?.?.
NEED READING GLASSES
Laser treatment generally involves reshaping the cornea – the clear, spherical tissue on the front of the eyeball
Until now, laser therapy could not be used for presbyopia, the age-related sight loss which leaves you needing reading glasses. However there are now two options.
INTRACOR: In this treatment, a laser makes five concentric rings in the cornea. This makes it bulge a little in the middle, creating a slight bifocal effect. The central cornea sees better for close work, but distance vision is unaffected. The treatment takes seconds and the effects are virtually instant, says the developer.
Most suitable for People with mild presbyopia with a prescription of +1.5 or less.
Pros: Treats presbyopia.
Cons: ‘This is relatively new and unproven and only for those with a small prescription for presbyopia,’ says Professor Gartry. There is the risk of some glare and haloes at night, but the developers say this normally settles within three to six months. It cannot be given to those who are short-sighted.
Cost: 2,200 per eye.
SUPRACOR: As with Lasik, a thin flap is created on the top of the eye to allow access to the cornea, explains Sheraz Daya, a consultant ophthalmologist at Centre For Sight. ‘I laser to leave a small raised area in the middle of the cornea to give better focusing on near objects, and flatten or steepen the outer section,’ he adds.
Most suitable for People with mild to severe presbyopia. Long-sightedness can also be corrected at the same time.
Pros: A more accurate option for presbyopia than Intracor.
Cons: Slight blurriness for distance in the first week. Some people have temporary short-sightedness, and there maybe some discomfort for the first day.
Cost: 2,600 per eye
SHORT-SIGHTED, LONG-SIGHTED AND ASTIGMATISM
ADVANCE ZYOPTIX WAVEFRONT TECHNOLOGY: Like most current techniques, this uses wavefront, where computer software scans the eye to map the defect before treatment.
But with this procedure, the eye is scanned many more times, meaning greater detail, explains Chidambara Pillai, a consultant refractive surgeon at Advanced Vision Care in Harley Street. A flap is opened on the cornea and the laser corrects the problem.
Most suitable for It removes less corneal tissue than Lasik, so it can treat patients with thin corneas.
Pros: ‘As well as improving what you see, it can lead to better-quality vision in poor lighting or for night driving,’ says Professor Gartry. ‘I have used this extensively and found it to give very good results, especially for astigmatism.’
Cons: It can lead to dry eyes and, in rare cases, temporary inflammation.
Cost: From 1,300 per eye.
Unknown side-effects: Some of the laser treatments are so new we do not know what their long-term effects will be
RELEX (Refractive Lenticule Extraction): Less invasive for short-sightedness. Instead of cutting a flap into the cornea, a laser reshapes it with micro pulses. These outline the tissue that’s to be removed. Then a small appliance a bit like tiny tweezers is inserted through a 3mm incision made in the centre of the cornea using a laser. This removes the tissue.
This takes four to five minutes. Vision is 80 per cent better instantly and reaches 100 per cent within a few days, according to trials in the UK, Germany and Denmark.
Most suitable for Those not able to have traditional surgery because of thin corneas and patients with very high prescriptions up to -13.
Pros: Less invasive, less post-operative discomfort and reduced risk of complications such as dry eye.
Cons: Less accurate than mainstream Lasik because there’s no wavefront mapping before surgery. ‘So unless you have thin corneas or a high prescription, it’s not one for you,’ says Professor Gartry.
Cost: 4,600 for both eyes.
CORNEA DAMAGE DUE TO ILLNESS OR SURGERY
TOPOGRAPHY-GUIDED LASIK/LASEK: Designed for problems caused by an irregular, misshapen cornea as a result of illness such as keratoconus, trauma or surgery.
‘This causes sight issues that glasses may not fully rectify and it can also make it impossible to wear contact lenses,’ says David Anderson, a consultant ophthalmic surgeon at Optegra.
The cornea is scanned to give a 3D image (that looks like the line on a map, hence the name ‘topography’).
The outer layer of cells of the cornea are gently pushed aside before a short burst of laser reshapes it. The patient may then see perfectly or be able to wear normal glasses. Vision should be clear within a week.
Most suitable for Patients with injuries to their corneas or people who have had corneal transplants.
Pros: ‘This may help smooth out corneal irregularities,’ says Professor Gartry.
Cons: A very new technique, so long-term effects are not known. ‘I am very uncomfortable with the suggestion this can be used for keratoconus, since removal of tissue potentially weakens the cornea further and a weak cornea is the fundamental problem in this condition,’ says Professor Gartry.
Cost: 2,000 per eye.