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Laser Eye Surgery Risks

With an expert surgeon and well selected patients, laser eye surgery risks are minimal

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

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.

Laser eye surgery risks and safety is primarily dependant on only operating on good candidates. With an expert surgeon and well selected patients, outcomes and safety are excellent.
David Allamby, surgeon
Laser eye surgery risks

Risk of results not lasting or vision deteriorating over time – How long does laser eye surgery last?

As we grow up, our bodies change; the same applies for our sight. Quite often, a child with far-sighted vision issues will ‘grow out of it’ and their vision will improve by the time they become teenagers. We’re also most likely to develop myopia (short-sight or nearsightedness) in our teens or even earlier, or in some cases a little bit older in the early 20s, with our prescription stabilising usually by some point between 21 and 30.

In general, the younger you are when you start to become short-sighted, the earlier your eyes will stabilise to their final prescription. Once stable, patients become eligible for laser eye treatment. If you were to have laser eye surgery too early, or whilst your eyes are still changing, you will be at risk of your vision deteriorating naturally as your myopia continues to progress, and you could again require glasses or further vision correction.

In general, providing your eyesight has remained stable for 1-2 years and your surgery for short-sight or astigmatism is carried out by a reputable and experienced surgeon, your distance vision should remain excellent.

There is no upper age limit to receiving laser eye surgery. While distance vision is fully correctable when treating short-sight and astigmatism, an additional focusing issue will arrive as your eyes start changing in your 40s, called presbyopia. Presbyopia (age-related long-sight or farsightedness) is an unavoidable condition where the eye’s ability to focus on near objects diminishes as we get older. It affects everyone by the age of 51. Even if you have been previously treated with laser eye surgery, your eyes can still be affected by presbyopia. You are able to have treatment to correct presbyopia, even if you have been previously treated for different sight problems. The two treatments we offer for presbyopia are LASIK Blended Vision and Lens Replacement Surgery, the latter also known as Refractive Lens Exchange, or RLE for short.

The type of treatment recommended to you will be totally dependant on your individual circumstances. Focus Clinic only ever carry out surgery on candidates that are deemed suitable. This helps minimise the risks and chances of complications. Laser eye surgery for presbyopia uses a technique called ‘LASIK Blended Vision’, where one eye allows for excellent distance vision and the other boosts clear reading. Those patients who have already had laser correction for myopia and/or astigmatism may still be able to have Blended Vision to restore blurry near focus once they reach middle age, following a thorough consultation.

At Focus Clinic, we offer a lifetime guarantee with all of our LASIK surgeries for short-sight when correcting blurry distance vision. Your Lifetime Care Guarantee means you can return at any time if you have additional questions on the quality of your vision. If you have distance vision correction for short-sight then any repeat laser eye treatments to correct a return of myopia in the first 10 years are included free of charge. (Terms and conditions apply, excludes any age-related changes and conditions unrelated to the primary treatment)

Laser eye surgery and your general health

As mentioned earlier, laser eye surgery is still surgery and should be treated with the same consideration you would apply for an operation anywhere else on your body. Although severe complications are very rare, it’s important that you take your time researching the type of surgery that is right for you, and discuss in detail any concerns you have as well as your current state of health or any conditions you have that may impact your recovery with your surgeon at the consultation stage.

Healthy individuals who are deemed suitable candidates are at minimal risk of complications to their vision, when operated on by an expert surgeon in a specialist clinic or hospital. The centre must not be a ‘conveyor belt’ approach or where patients feel pressure to go ahead, as risks may be elevated.

People who have uncontrolled medical conditions or uncontrolled autoimmune diseases like Sjogren’s syndrome, type 1 diabetes, AIDS and rheumatoid arthritis are at a greater risk of infection and other complications due to the body’s impaired ability to heal, or may be prone to abnormal healing.

We carefully screen and select patients for surgery to ensure the lowest possible risk of complications, so if you have a history of medical problems, or an existing condition that may affect your treatment, please make sure you discuss it with the surgeon at your consultation. He or she can advise if you are a good candidate or if risks are increased and to what degree, depending on the specific ailment.

The risk of being harmed if you move during laser eye surgery

Contrary to common belief, nothing untoward will happen if you move during your laser eye treatment! This is the most common worry patients have before their treatment, and the most common question about risks during the laser eye surgery procedure. The other most common question is Will it hurt? (Answer = No).

Before the surgery takes place, you are given anaesthetic eye drops to make sure that you won’t feel any pain or any discomfort while your eye is open. This makes keeping your eyes open feel a lot more comfortable. It will feel as if you are blinking normally throughout the procedure, even though your eye isn’t closing. Just blink normally all the way through your treatment.

It’s important to remember that the lasers are only active for approximately 30 seconds of the total duration of the surgery, which is around 5 minutes per eye. The remaining 90% of the operation time is carried by your surgeon manually – both expertly and precisely using special instruments. If you are moving your head, your doctor will just advise you to keep still and concentrate on the flashing LED light visible directly ahead.

During the very short time of actual operation of the lasers, sophisticated and advanced tracking technology is used to confirm the position of your eye before every pulse, 400 times a second. The tracking system can respond faster than you can move your eyes, so the treatment is always exactly in the correct position. All you have to do is look at the flashing green light directly in front of you and your surgeon will do the rest.

The key role of your surgeon in performing the more than 150 steps needed per eye, as well as the essential pre-operative checks before going ahead, is another reason why you should take time to research your doctor and their success rates. All these stages and steps must be carried out in a relaxed and calm environment to ensure the best results, and not a ‘conveyor belt’ approach which could increase risk and result in less than 20/20 vision.

Focus Clinic is proud to have a 100% success rate for 20/20 vision (or better) all common short-sighted prescriptions.

The risk of laser eye surgery making your sight worse – Can laser eye surgery make your vision worse?

As mentioned above, the lasers are only active for a minimal part of your surgery. The great majority of your surgery at Focus is made up of your surgeon performing more than 150 steps to ensure complete precision. Before you even get to the surgery stage, your sight is thoroughly tested by a series of machines and then by your consultant surgeon to give a 100% accurate reading of your vision and prescription. This is far more detailed than your usual optician’s checks. The results from these checks are inputted into the lasers used during surgery. These data tell the excimer laser exactly where to place the several thousand pulses in order to change the curvature of your cornea, thus improving your vision.

If a clinic is performing a high volume of cases per day, the chance of making an error when assessing the eyes, taking pre-operative measurements or inputting your details into the laser is elevated. We will never carry out more than 8 surgeries in any one day. This allows our surgeons to spend enough time (approximately an hour per patient) to go through the dozens of checks without errors. Some clinics routinely pay a surgeon to treat 20-30 patients a day, and you should avoid such centres.

If you are thinking of going to a laser eye surgeon or clinic who treats many more than 8 patients per day, you must question how these checks are carried out with due care and attention to detail. Our record is 100% for common prescriptions and we know of no other surgeon or clinic that has matched this success rate. Part of that success is carrying out fewer procedures per day and ensuring that each one is done perfectly. Some clinics show a success rate for 20/20 vision of 95% or even 98%. However, there is a big difference between 98% and 100% success, especially if you are in that 2%.

The chances of your sight being made significantly worse by laser eye surgery is actually rare, with an incidence of 1 in 10,000 cases, providing the surgery is carried out by a reputable and experienced surgeon in a quality setting. Less serious issues requiring some remedial treatment occur approximately 1 in 1,000 cases.

At Focus Clinic, we offer a Lifetime Care Guarantee. Whenever we perform LASIK for short-sight to improve distance vision, we expect the result to be permanent. (It is still normal to develop the age-related need for reading glasses in middle age and beyond, which is a different condition from short-sight.) If your distance vision deteriorates over the years due to a return of short-sightedness, we will offer re-treatment to those suitable for surgery without any charge, even years later.

Taking part in activities after laser eye surgery

For a few hours after your surgery, your eyes can feel a little gritty and home rest is recommended for this period. After four hours your eyes will be comfortable, clear, and your vision is usually excellent – at 20/20 or better. With LASIK, you will be able to return to work the following day after your review appointment, which is held at Focus Clinic. We advise that you avoid getting water in your eyes during the first 48 hours after surgery. It’s also advisable to refrain from saunas and steam rooms for the following two weeks.

As for sporting activities, we advise that you do not take part in any sporting activities during the first week after surgery. This gives your eyes enough time to fully heal and recover. After this time, you can resume all normal activities.

Short-haul flights are fine once you have had your next-day check at the clinic. Long-haul flights can be taken after you have had your second check-up, which is scheduled for one week after treatment.

So, Is Laser Eye Surgery Safe?

The overall risks from laser eye surgery are minimal providing you are:

  • a suitable candidate
  • your surgery is performed by an expert specialist surgeon
  • treatment takes place in a low-volume setting without a ‘conveyor belt’ approach, with no more than 8 patients per day
  • you experienced no pressure to go ahead with surgery

If you have the above four factors in place, your risks of complications from laser eye surgery are very low. Safety for each person is, of course, based on a thorough individual assessment and examination, and may require pre-treatment, e.g. for dry eyes, prior to laser correction.

We will always advise patients to do their research to ensure their chosen surgeon has the highest success rates, lowest complication rates and a clean, well equipped clinical environment. In general, suitable patients having laser eye surgery is safe with very satisfying and long-lasting results.

If you are interested in vision correction at Focus Clinic please call us on 0207 307 8250 and book a free consultation.

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16th Jun


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 Samar Hamada