The surgery usually involves reshaping the cornea – the transparent layer covering the front of the eye. This is done using a type of laser known as an excimer laser. Different techniques are used to correct short sight (myopia), long sight (hypermetropia) and astigmatism.
You usually have to be aged 21 or over and your prescription should not have changed for at least two years.
The Royal College of Ophthalmologists (RCO) recommends that doctors doing the surgery should be registered ophthalmologists and have additional specialist training in laser refractive surgery.
Types of laser eye surgery
Your optometrist can discuss with you the various methods of correcting your vision, and the advantages and disadvantages of spectacles, contact lenses and laser refractive surgery.
Here's a rundown of some of the most common types of laser surgery:
LASIK (laser in situ keratomileusis)
LASIK has been performed since the mid-1990s, and is the most common procedure. Long-sightedness and short-sightedness can both be corrected with LASIK, but it may not be suitable for correcting high prescriptions. Surgeons cut across the cornea and raise a flap of tissue. The exposed surface is then reshaped using the excimer laser, and the flap is replaced.
PRK (photorefractive keratectomy)
PRK has been performed since the late 1980s, but since the development of LASIK and LASEK (see below), it's now mainly used for correcting low prescriptions. The cornea is reshaped by the excimer laser without a flap of tissue being cut.
LASEK (laser epithelial keratomileusis)
LASEK is similar to PRK but the surface layer (epithelium) of the cornea is retained as a flap. Retaining the epithelium is thought to prevent complications and speed up healing.
Wavefront-guided LASIK is a tailor-made form of LASIK that reduces the natural irregularities of the eye as well as correcting your eyesight.
What are the risks of laser eye surgery?
Complications occur in less than 5% of cases, but check with your consultant that they have outlined all the risks. Most people are back at work within a few days to a week.
Some people have a problem with dry eyes in the months after surgery. Artificial tears can help with this. Other patients experience glare or halo effects when driving at night in the weeks or months after treatment. This is more likely if a high degree of long- or short-sightedness is corrected.
In rare cases, too much thinning of the eye wall can make the shape of the eye unstable after treatment. Severe loss of vision is very rare.
It's important to find out how frequently your surgeon has had complications, and why.
You can find more information about the risks associated with laser eye surgery in the Patient Guide to Excimer Laser Refractive Surgery, published by the RCO. You can also read more about laser eye surgery in the NICE guidance, Photorefractive (laser) surgery for the correction of refractive errors.