Laser Eye Surgery Risks
When the first Photorefractive Keratectomy (PRK) laser vision correction surgery was performed in 1989, there were a lot of unknowns regarding the risks, effectiveness and longevity of the surgery, with complications such as glare, blurred vision because of a residual prescription, haze and infections occurring much more often. Fast forward 25 years to the present day and the techniques and equipment used are far more advanced, meaning the risks of having laser eye surgery are minimal and the outcome far more precise.
Despite refractive procedures now being safer than they have ever been, with various complications being greatly reduced or even eliminated, laser eye surgery it is still surgery and should always be treated as such – with due care and consideration.
Is Laser Eye Surgery Safe?
Having laser eye surgery is the same as having any surgery – you’re safe as long as your surgeon is qualified, experienced and reputable, as well as the clinical setting not being overly commercial. We compare having laser eye surgery to driving. Is driving safe? Well that depends on the driver, the condition of the car and the environment they’re driving in.
In 2015, most laser eye surgery complications arose when the person treated was not an ideal candidate. This comes down to the surgeon and clinical setting. If it is a high volume / sales-orientated environment where less time is spent on assessment and selection and more time is spent trying to get as many people as possible treated, risks will rise.
Despite this, serious complications with LASIK or PRK surgeries are actually rare providing the patient is suitable and known risks have been reduced e.g. from pre-treatment of any dry eye to improve post-operative healing and recovery. The chance of experiencing complications from LASIK, including various minor ones, has been documented to be less than one percent.
All vision correction options have an element of risk. For example, it is well known that there is a higher risk of infection from wearing contact lenses long-term than from LASIK laser eye surgery. Providing you are deemed a suitable candidate and the surgeon is reputable and experienced, laser eye surgery is considered safe.
What Are the Risks of Laser Eye Surgery?
Although you may not think it, the biggest risk in the laser eye surgery process arises at the consultation stage. Laser eye surgery safety is primarily about only operating on suitable candidates. LASIK and PRK surgery outcomes are almost always favourable for those who don’t have any indications of increased risk and are suitable to proceed; however, not everyone is deemed a suitable candidate.
A good indication of the success of any clinic is the percentage of patients who require a second ‘top-up’ procedure to enhance the result, known as an enhancement or re-treatment. The LASIK protocols created and followed at Focus Clinic have led to a remarkably low re-treatment rate, at less than 1% of typically short-sighted cases (2014 data), compared to between 3% and 9% in published studies. Primary treatments, even for high levels of myopia, remain consistently accurate and relatively risk-free.
As with any medical intervention, there are possible risks and side-effects that can occur. All of these will be discussed at your consultation. It’s important that you are aware of the potential issues before you go ahead with surgery and discuss any concerns you have at your consultation.
Reducing the Risks of Laser Eye Surgery
There are two types of laser eye surgery, which significantly reduces the risks of problems occurring post surgery. Sometimes clinics list these as ‘optional extras’, but they are essential to getting the safety available from modern laser eye surgery.
Wavefront optics (often referred to just as ‘wavefront’) is an advanced laser treatment pattern that leaves a more natural shape to the curvature of the cornea after treatment. Older non-wavefront laser treatments tended to flatten the central cornea without maintaining its so-called ‘aspheric’ shape. (This aspheric shape is found in high quality camera lenses, and gives a sharper, crisper focus.) You may see the terms ‘wavefront optimised’ and ‘wavefront-guided’, but there is no statistical difference in outcomes between the two, confirmed by multiple research studies.
Wavefront surgery has meant that a lot of the side-effects previously associated with laser vision correction (such as halos and glare at night) are now much rarer than before.
The take-home message is always choose the ‘wavefront’ option. At Focus Clinic, we only offer wavefront-based treatments.
Femtosecond laser LASIK
Modern LASIK uses two lasers. The first is a so-called ‘femtosecond’ laser which creates the flap in the top layers of the cornea, rather than using an old-fashioned blade system, called a microkeratome.
This type of surgery is a cheaper alternative to using a more sophisticated laser, where the surgeon will use a scalpel to manually cut the corneal flap to allow the laser to correct site. You are more likely to experience adverse reactions to this type of surgery as a surgeon using a blade device will never be able to cut the corneal flap as precisely and cleanly as a laser. You are at a greater risk of reduced corneal strength and persistent dry eyes, as the healing process is slower with potentially thicker flaps made by the blade, than when the corneal flap is created by a laser. For this reason, Focus Clinic only offer laser-created flaps in their LASIK surgery.
The femtosecond laser is the first stage of the procedure, with the second stage involving a different laser to correct the curve of the cornea, thus correcting vision. We provide you with a course of drops following your surgery to help prevent any infection, inflammation and to minimize symptoms of dry eyes.
Risk of Complications Post-surgery
Overall, the risks of a complication requiring additional treatment, either laser or other technique, is approximately 1 in 1000, and where there is no significant visual loss. The chance of a more serious complication which would affect vision in one eye or the other, or both, is 1 in 10,000.
Most Common Laser Eye Surgery Side-Effects
The most common complication reported post-surgery is persistent dry eyes, with published studies showing rates of up to 20-50% of patients. At Focus Clinic, correct patient selection and pre-treatment of any existing dry eye has dramatically improved these rates, dropping the post-op incidence to less than 1%.
It is important to note that women commonly suffer from dry eyes after menopause. Men can also be affected by this condition in later life. Dry eyes before treatment can increase the risks of persistent, increased dry eyes after laser eye surgery. It is therefore highly recommended that if you suffer from dry eyes, that you get this condition treated before laser eye surgery is performed. If your eyes are very dry beforehand, your risks are increased and it is likely better to avoid laser vision surgery. Another option for selected short-sighted patients is an ICL (implantable collamer lens) with far less risk of induced dryness.
Other, more rare, complications include infections (1 in 10,000 cases), which is much less common than infections leading to vision loss from contact lenses (1 in 2,000 cases). Hence, contact lenses are at least 5 times more likely to cause loss of vision from micro-organisms compared to LASIK.
Impaired night vision such as halos or glare can occur after laser treatment and are mainly linked with the degree of prescription treated; it is most often seen in the high and extreme myopia cases, typically of -8.00 dioptres and higher. Having a normal or small pupil in the dark appears to protect against getting night vision problems. A better option for some patients with very high prescriptions is placing a contact-lens type implant inside the eye, known as an ICL (implantable collamer lens). ICLs have been a major breakthrough for extreme myopia, with much less chance of night vision problems.