LASEK (Laser-Assisted Sub-Epithelial Keratectomy) Laser Eye Surgery

LASEK eye surgery (short for Laser-Assisted Sub-Epithelial Keratectomy) is a type of corrective laser eye surgery, used to improve vision and reduce the need for glasses or contact lenses in people with astigmatism, long-sightedness and short-sightedness.

Laser eye surgery is one of the most common elective surgeries in the world, with the number of people electing to have the more commonly practiced methods of LASIK, LASEK or PRK laser eye surgery increasing year on year. Those who have it done can expect their vision to drastically improve following surgery, with over 90% of patients experiencing their “ideal vision” within around two weeks following surgery.

The very first LASEK procedure was performed in America in 1996 by ophthalmologist and refractive surgeon Dimitri Azar. 

LASEK eye surgery can permanently improve eyesight, provided that you are the right candidate. If you are considering LASEK eye surgery, the following information should give you a basic understanding of the procedure. It can’t answer all of your questions, as the outcome of the procedure depends on the individual person and practitioner. Please ask an ophthalmic surgeon about anything you don’t understand.

LASEK is a type of corrective laser eye surgery that is designed to treat and improve various eyesight conditions and vision problems. 

Local anaesthetic eye drops will be dropped into the eye before treatment, meaning that the treatment itself is virtually painless. The procedure involves the outer layer of the cornea (the epithelium) being detached from the cornea following weakening or loosening of the epithelial cells with a 20% alcohol solution. (This differs from LASIK where a knife blade or femtosecond laser is used to cut a flap much deeper into the layers of the cornea). The epithelium is then lifted or rolled back to allow access to the corneal tissue below. An excimer laser is then used to permanently alter the shape of an area called the anterior central cornea by removing a small amount of tissue from the corneal stroma through ablation or vaporisation. Once complete the epithelium can be lowered back down or pushed back over and will completely heal within a few days. 

With LASEK eye surgery the laser application is performed at a more superficial level than with LASIK procedures, making it more suitable for those people with higher degrees of vision errors.

The process of the laser altering the shape of the anterior central cornea allows light to travel through it to the retina at the back of the eye, improving and focussing the vision. The actual laser part of the procedure takes less than 60 seconds per eye, although the pre-surgical evaluations of the eye and the correction needed will actually take longer. 

LASEK aims to correct the vision in people with various eyesight conditions, including short-sightedness, long-sightedness and astigmatism. 

Short-sightedness is a condition also known as myopia which means that a person may have difficulty seeing objects that are in the far distance; in other words they can clearly see objects that are right in front of them whilst objects in the distance could become increasingly blurry the further away they are. 

Long-sightedness is a condition known as hyperopia, which means that a person may have difficulty in seeing objects that are close in front of their eyes such as the words on a page in a book or magazine or the images on a television screen. 

People with astigmatism, which is an optical defect caused by the shape of the eye, tend to also experience blurry vision. 

You can expect a great improvement in your eyesight within the first few weeks following the surgery, although it might take around one to three months to achieve a final result. Some patients experience vision of 20/25 or even greater, once their eyes are healed.

It cannot however treat or prevent presbyopia which is the situation whereby with age there is a progressively diminishing ability of the ability of the eye to focus on near objects, meaning that as may people age they start to require ‘reading glasses’.

There are a number of different names for variations of LASEK surgery, including ASA LASEK (Advanced Surface Ablation) which uses an amoilis brush to sweep back the epithelial cells, and M-LASEK, which uses mitomycin, an anti-metabolite to try to reduce hazy vision after the operation for those cases where extensive correction is required.  All aim to remove the epithelium out of the way before applying the excimer laser, rather than creating a corneal flap as with LASIK procedures.

LASEK can sometimes be marketed as ‘No-flap LASIK’ or ‘Blade Free LASIK’ as the term LASIK is more commonly known when referring to laser eye surgery procedures. 

Another procedure, PRK (PhotoRefractive Keratectomy) laser eye surgery, is very similar to LASEK surgery and pre-dates it as a technique. In PRK surgery, the epithelium (the outer layer of the cornea) is removed completely and then the excimer laser is used to treat the cornea. This does however mean more recovery time and pain is likely with PRK than with LASEK.

With LASEK surgery, if the epithelial flap is too weak to be laid back in place after the laser treatment, it will be removed and the LASEK surgery will be converted to a PRK surgery. The epithelium can re-grow very quickly and will be replaced within a matter of days.

A Cochrane systemic review published in January 2013 comparing the safety and efficacy of LASIK and PRK eye surgery for short-sightedness by reviewing all available study and trial data concluded that; “LASIK gives a faster visual recovery and is a less painful technique than PRK. The two techniques appear to give similar outcomes one year after surgery. Further trials using contemporary techniques are required to determine whether LASIK and PRK as currently practised are equally safe.” 

Another variation is epi-LASEK or epithelial LASEK. This uses an epikeratome, a similar surgical tool to the microkeratome oscillating blade used for LASIK. The epikeratome uses a blunt separator rather than a sharp blade to separate the surface sheet of epithelial cells from the permanent corneal tissue following the application of the 20% alcohol solution; (this is not included in the epi-LASIK version). Both procedures epi-LASIK and epi-LASEK are suited to those people whose corneas are too flat for traditional LASIK.

Wavefront guided technologies are used with LASEK as well as LASIK to aim to achieve an ‘optically perfect’ vision correction.

Before surgery, you will undergo an evaluation with a specialist ophthalmic practitioner who will map out your cornea, test refraction and measure pupil dilation, pupil pressure and corneal thickness. They will explain everything to you to make sure that you understand what to expect before, during and after the surgery.

Rigid glass permeable lenses need to be removed for at least three weeks prior to surgery, while all other contact lenses need to be removed for at least three days prior to surgery. 

You should eat only a light meal and take only any prescribed medication before the procedure. You will be asked to arrive for surgery with a clean face, no makeup and hair tied back if necessary. You should not wear hair clips or hair bands at the back of the head if you have long hair as this could prevent your head from lying flat during the surgery. 

Before LASEK surgery, the eyes are numbed with local anaesthetic eye drops. 

The outer layer of the cornea will be treated with an 20% alcohol solution and then detached from the cornea. The outer layer will then either be rolled back or lifted to allow access to the underlying corneal tissue. 

Following the corneal mapping and the measurements taken during your evaluation, an excimer laser will then ablate (vaporise) some of the corneal tissue in order to allow light to pass evenly through the cornea to the retina at the back of the eye.  A computer system tracks the position of the eye between 60 and 4,000 times per second, depending on the particular laser used by the practitioner, which then redirects the pulses of the laser which are delivered so that precise placement can be achieved. 

The outer corneal tissue will then be put back into place and a bandage contact lens put into the eye for up to four days in order to facilitate healing. 

You will be given steroid eye drops to use for several weeks following the surgery in order to aid healing.  

You are usually advised to wear sunglasses or dark eyeglasses following surgery for a few days, or even up to a few weeks, in order to protect the eyes from bright lights and sunshine. Some people will also be given eye goggles to wear at night to prevent rubbing of the eyes and to reduce the likelihood that they will develop dry eyes. Others will be given moisturising tear drops to moisturise the eyes. 

It's recommended that LASEK patients do not drive or operate heavy machinery for several days following the surgery, although depending on the outcome of your surgery, your doctor might recommend that you wait for a few weeks. 

You'll need to see a doctor one week after surgery with follow-up appointments at three months and six months.

It may also be recommended that you avoid applying lotions, creams or makeup around the eye area for at least two weeks and you should also avoid swimming pools, Jacuzzis or hot tubs for at least two months, as these have been linked with an increased risk of infection. Contact sports, particularly strenuous contact sports, should be avoided for around one month.

If you experience severe pain or discomfort following the procedure, or any other debilitating side effects, you should contact the clinic or surgeon who treated you for advice immediately. Most doctors will recommend that you take painkillers, if necessary, to control the pain, but any unusual effects will need to be checked.

LASEK eye surgery is better suited to patients with very thin or steep corneas, as thin flaps make it difficult for the surgeon to create a suitable flap for a LASIK surgical procedure. During LASIK surgery, trauma to the eye is more severe than with LASEK surgery (due to the flap creation with LASIK) and so LASEK surgery might also be better suited to patients who engage in leisure or sports activities where their eyes are at a greater risk of being injured. 

Because LASEK eye surgery does not create a deep flap, the corneal nerves that are responsible for the tear reflex are not affected, meaning that the surgery is also more suitable for people with dry-eye syndrome.

LASEK eye surgery will only be suitable for people who are over 18, who have had stable vision and an optical prescription for at least two years. 

People with mild myopia, hyperopia and astigmatism might not be suitable candidates. 

Those who are pregnant, breastfeeding, diabetic or arthritic may also not be suitable for surgery as well as those with occular diseases such as glaucoma or those with a history of experiencing side-effects from steroids.

Adults who are in general good health and with realistic expectations of the outcome of the procedure are ideal candidates.

Only fully trained and qualified ophthalmic physicians or laser eye surgeons should perform LASEK eye surgery.

For more information about practitioner training, qualifications and relevant medical organisations please view the information contained within the Legislation section of the Consulting Room.

LASEK eye surgery is a corrective eye surgery that can improve the vision of patients with hyperopia (long-sightedness), myopia (short-sightedness) and astigmatism. 

It's considered to be a safe, non-invasive procedure that can permanently improve the vision of patients within a few weeks, removing the need for glasses and contact lenses. 

However, some side effects are common with LASEK surgery in the first few weeks and months following surgery, which once resolved will leave a person with drastically improved vision, although it some cases this may not be as good as the vision obtained whilst wearing glasses or contact lenses.

The cost of LASEK surgery differs depending on your prescription and the exact nature of procedure required to correct your vision. LASEK can cost from £500 to £1,300 per eye, while PRK can cost from £600 to £900 per eye.