Everything you need to know about laser eye surgery
What is laser eye surgery?
Laser eye surgery is a corrective vision surgery that is used to treat short-sightedness (myopia) and long-sightedness (hyperopia), as well as astigmatism. As the name reveals, during the procedure lasers are used to reshape the cornea and allow the eyes to focus better.
Laser eye surgery was approved by the FDA and became commercially available in 1995 and is currently the one of the very few options for treatment that can offer a chance of permanent vision correction.
Since its first introduction to the general public, laser eye surgery has come a long way. Nowadays, there are several options available in the UK, to ensure that different levels of prescriptions can be catered for and corrected, offering an option for all types of eyes.
Types of laser eye surgery
After a comprehensive eye examination and discussions about expectations and consequences regarding the surgery and outcome thereof, your eye doctor will determine which type of vision correction surgery works for your eyes. This ensures the best result as well as maintaining healthy eyes.
The main options for laser eye surgery in the UK are LASIK, LASEK, PRK and SMILE.
Epithelial laser-assisted in-situ keratomileusis (LASIK)
LASIK is the most applied form of laser eye surgery. Two types of lasers work together: one is used to open a thin flap of the cornea while the second laser reshapes it to counteract the refractive error.
After the surgery, the flap is replaced over the cornea and re-attaches itself within 24-48 hours.
LASIK is a quick procedure that doesn’t take longer than 15 minutes and offers results shortly after the surgery. It is suitable for the correction of myopia and hyperopia, as well as astigmatism.
Laser-assisted subepithelial keratectomy (LASEK)
During LASEK surgery, the epithelial layer of the cornea is removed to access the layers underneath and change its shape with a laser. The epithelial layer removed for this procedure is thinner than the flap created for LASIK and is suitable for candidates that may experience difficulties during the recovery process of LASIK. The epithelium is placed back over the cornea after the surgery and reattaches itself. A bandage contact lens is often used to protect the eyes during the healing process.
The procedure takes approximately 5 minutes per eye and is available for correction of short-sightedness, long-sightedness and astigmatism. The full effect of the vision correction may not be restored until two weeks after the surgery and the procedure is said to be slightly more painful than LASIK.
Photorefractive keratectomy (PRK)
PRK is the oldest form of laser eye surgery and is a similar process to LASEK. The top layer of the cornea, the epithelium, is removed to access and reshape the underlying cornea with a laser. However, as opposed to replacing the epithelium after the surgery, it is left to regenerate naturally. PRK is suitable for the correction of myopia and hyperopia, as well as astigmatism. The procedure takes approximately 10-15 minutes, and the desired restoration of 20/20 vision is usually achieved 4-8 weeks after the surgery.
Small incision lenticule extraction (SMILE)
SMILE is the laser eye surgery option that became commercially available most recently in 2011. It can only be used to correct short-sightedness and astigmatism, not long-sightedness.
After numbing the eyes, the first step of SMILE is a pulsating laser on the centre of the cornea, creating small bubbles outlining the area that needs to be removed. The laser then continues to create a small incision through which the surgeon can draw out the tissue, which will change the shape of the cornea, resulting in improved vision.
This procedure takes approximately 15 minutes per eye and the full results settle within a few weeks. The benefit of SMILE treatment is the minimal disruption of the cornea, which decreases the risk of dry eye developing after the procedure.
The process of laser eye surgery
No matter which type of laser eye surgery is recommended to you, a certain amount of preparation is required, as well as points to consider for the correct aftercare. This ensures that the eyes can heal properly and reach the desired level of vision correction without complications.
Before the surgery
Your eye doctor will not only examine your eyes thoroughly prior to the surgery, they will also discuss your expectations of the results and the pros and cons to ensure your decision about the procedure is well informed.
Contact lens wearers need to discontinue wear of their lenses for at least 2 weeks leading up to the surgery. No matter the lens type, regular contact lens wear will alter the shape of your cornea. By not wearing lenses for several weeks, the cornea regains its original shape, which is required for the surgery.
On the day leading up to the surgery, any types of lotions, creams or make-up should be avoided around the eyes.
Patients should arrange for transport to and from the clinic, as your vision will still be blurry immediately after the surgery and you won’t be fit to drive yourself.
During the surgery
The exact procedure differs with each type of surgery, but they are all performed while you are awake. Only numbing eye drops will be applied to your eyes, for you to avoid feeling any discomfort during the surgery.
The surgeon will clean your eyes before they are held open with a speculum while they work on your eyes.
During the short time that the surgery takes, you are asked to stare at a fixed spot and not to move your eyes. Should you move, however, rest assured that all lasers are equipped with a sensor that recognises even miniscule movements and stop immediately.
After the surgery
Immediately after the surgery you will be provided with a protective shield that is placed around your eyes like goggles. Your eyes may itch or feel as though a foreign object is stuck in them, but it is very import not to rub them, as this can lead to complications in the healing process. The goggles must also be worn whilst sleeping, to protect you from subconsciously rubbing your healing eyes at night.
There will be a scheduled check-up for the day after the surgery, in which the ophthalmologist checks that your eyes are healing properly.
During the next four weeks following the surgery, avoid any sports or heavy physical activities. Swimming or bathing should be avoided for eight weeks after the surgery.
Your vision may fluctuate after the surgery and might only stabilise after up to six months later, depending on the condition of your eyes before the surgery and what type of surgery was performed.
Is laser eye surgery safe?
When you follow your ophthalmologist's advice and do your own research, laser eye surgery is a safe option for vision correction. Listen carefully to your eye doctor when discussing your options and consider any possible risks to make sure you are happy with the option your doctor decides works best for your eyes.
A study from the Journal of Cataract and Refractive Surgery shows that laser eye surgery for the correction of myopia and hyperopia (between -5.00 and +3.00 dioptre) has a success rate of approximately 96%, meaning these patients won’t require glasses again. Even patients with more severe refractive errors have a 90% chance of regaining 20/20 vision after surgery.
The chances that you lose your vision after a failed surgery are less than 1%, this is extremely rare.
However, there are some reactions caused by the surgery that occur more commonly, including dry eyes, glare and halos at night. These conditions are often a side effect while your eyes are healing and may resolve within six months following the surgery.
Is the surgery painful?
Laser eye surgery is not a painful procedure, you may only feel a slight pressure on your eyes during the surgery.
Who is it suitable for?
Although laser eye surgery is a suitable form of vision correction for most people, there are some exceptions depending on the age, eye health and general health of the candidate.
For laser eye surgery in the UK, you need to be at least 18 years old, ideally with a prescription that has been stable for the past two years.
Later in life, over the age of 40, you may no longer be suitable for laser eye surgery because presbyopia that comes with age is not treatable through laser surgery. Presbyopia is a condition caused when the lens of your eye becomes inflexible with age.
Those with autoimmune diseases may not be suitable for laser eye treatments, as well as those with chronic health conditions that affect the healing process of their bodies. If you take medication that causes dry eyes, you may also not be a suitable candidate for laser eye surgery.
Women who are pregnant or are trying to become pregnant are not recommended to undergo laser eye surgery either, as hormonal changes during pregnancy can affect their eyesight and eye health.
If you have a high or severe form of any refractive error, laser eye surgery may only reduce this error, which means you will still require glasses or contact lenses to correct your vision after surgery. Should you expect complete vision correction as a result, your ophthalmologist may advise against laser eye surgery of any form to avoid disappointment.
Eye conditions such as keratoconus cause a thinning of the cornea, if you are at genetic risk of developing corneal dystrophies, you may not be suitable for laser eye surgery.
Chronic dry eye may be worsened through laser eye surgery, so most eye care professionals advise against laser vision correction treatment here.
The costs of laser eye surgery depend on which type of surgery you decide on and how intense the refractive error you wish to correct is.
Additionally, each private eye clinic offering surgery differs slightly in price.
Average cost of laser eye surgery in the UK
In the UK, laser eye surgery is not covered by the NHS, unless it is performed for medical reasons.
At most private eye clinics LASEK is the most affordable option, with average costs around £1,500 per eye. LASIK surgery is slightly more expensive but usually does not exceed £2,700 per eye.