Risks and Complications

There is a risk in performing any kind of surgery and this also applies to laser eye corrections like PRK, LASEK, Epi-LASIK & LASIK. However serious or sight threatening complications are rare. The risk (or chance) of suffering a vision damaging complication following laser eye correction is small, perhaps of the order of less than 1%; but the possibility of an unsatisfactory result can never be zero. If a complication occurs treatment may be available but it is possible that even after this treatment there may be some permanent loss of vision. For example an infection may be treated with antibiotics but even after the bacteria have been eliminated a corneal scar may remain.

Very occasionally the best achievable vision will be worse after treatment than before, even with the use of spectacles or contact lenses.

Sometimes less serious but unexpected problems arise following laser eye correction. These may require extra treatment or additional surgery but in the end the result is satisfactory.

The following are some examples of problems that can occur following laser eye correction. This list is not exhaustive:

Infection

The risk of acquiring a bacterial infection of the cornea following laser treatment is small. It is perhaps about the same as the risk of acquiring a similar infection from wearing a soft contact lens. In order to reduce the risk of corneal infection to a minimum the eye and lashes are flushed with an Iodine containing antiseptic immediately prior to the laser treatment and antibiotic eye drops are used following the treatment. For patients having laser treatment to both eyes on the same occasion, and to avoid transfer of micro-organisms from one eye to the other, separate instruments are used for the two eyes. We never use instruments on the second eye that have just been used on the first eye.

LASIK Flap complications

As part of the LASIK procedure the cornea is cut to create a thin hinged flap. This is reflected to allow the laser to be placed deeper within the corneal tissue (i.e. away from the surface of the cornea). It is possible for problems to occur when creating this flap. It may be cut free rather than being attached with a hinge or it may be cut unevenly or imperfectly. If this occurs the surgeon may decide to discontinue the treatment. In the hours and days following treatment the flap may become moved or wrinkled. The epithelium, which belongs on the surface of the cornea, may grow beneath the flap and disturb vision; this is called "epithelial in-growth". If any of these events occur further surgery may be required.

Night glare, halos and starburst

Some people who have never had laser eye correction experience these phenomena. They occur in part because of inappropriate scatter of light as it enters the eye. For example it can occur due to reflection of light from the edge of spectacles or contact lenses, or from rain drops on spectacles or the car windscreen. These phenomena are more likely to be experienced at night when the pupil of the eye dilates (becomes larger). The focus of any optical device, including the eye, is less perfect with a larger "pupil" as the optical aberrations become worse in this state. It is possible for these visual phenomena to become worse and more troublesome after laser eye correction. To reduce this possibility to a minimum the size of the pupil in dim lighting is assessed before surgery. The area of cornea treated with the laser is then arranged to be appropriate for the pupil size of the individual patient.

Laser correction of myopia (short sight) involves slightly flattening the centre of the cornea. If this is all that is done the optical aberrations of the eye (e.g. "the spherical aberration") may be made worse. The laser treatment can be "customised" so as to counter this effect, i.e. the laser treatment can include an element which compensates for potential changes to the aberrations of the eye. This technology also reduces the possibility of unwanted halos and starburst etc.

Fluctuating vision

In the early days after treatment vision may be clearer some days than others; or may even vary from blink to blink. In part this is due to the wetting of the eye and the quality of the tear film on the surface of the cornea. There is inevitably a period of recovery following the treatment. It may take a little while for the focus (short/long sightedness) of the eye to settle (bed down) and for the quality of vision to return to normal.

Post-operative discomfort

There is inevitably some discomfort after the treatment. The extent of this will depend somewhat on the type of treatment that has been performed. For LASIK there is usually some grittiness, light sensitivity and watering of the eyes for a few hours following treatment but this usually settles by that evening. For PRK and LASEK the eye can be bothersome and uncomfortable (disturbing sleep) for about 2 days & nights. For Epi-LASIK the experience is perhaps midway bewteen LASIK and PRK/LASEK. However discomfort/pain is a subjective thing and it varies a lot from one patient to another. Various drops and medications are provided to help patient through this period of discomfort.

Dry Eyes

Laser eye correction disturbs the wetting of the surface of the eye. LASIK tends to do this more than the various types of surface laser treatment. The surface of the cornea is kept healthy by a tear film that is recreated with each blink. This tear film should remain a thin even and intact film between blinks. Corneal laser treatment may compromise the ability of the eye to form a normal quality tear film. This may cause the eye to become uncomfortable and may cause disturbance and fluctuation in vision. Any person with severely dry eyes should not therefore have laser eye correction. Usually the wetting of the eye returns to its normal pre-treatment state within 3 months of the laser treatment. Lubricant eye drops are provided during this period.

Consent form

Before proceeding with laser eye correction it is important that you become fully informed of the risks and issues involved in having such surgery. To this end we have a comprehensive consent form for each type of procedure which goes through the individual risks, and some other issues which you need to be aware of. The appropriate form(s) will be given to you at the time of your consultation with our surgeon; although if you wish to have sight of it before then please contact and we will be happy to arrange this. Our usual practice is that you take the consent document home following your consultation to read through in your own un-pressured time. Within the consent document the issues are broken down into manageable statements. When you understand and are comfortable with each individual statement you are asked to initial against it. If there are any points that you are not comfortable with or do not fully understand then leave that statement and raise it for further discussion and explanation with us.

If you have any questions relating to the risks of having laser eye correction please do not hesitate to contact us either by FREEPHONE 0800 781 7177 or by clicking here.