LASIK (Laser In-Situ Keratomilieusis)

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The excimer laser emits short wavelength ultraviolet light which has the property of breaking the bonds between the molecules of the cornea, the clear ‘front window’ of the eye. The process is remarkably gentle and occurs without any burning of the tissue. The excimer laser reshapes the cornea, altering its focusing power to correct the eye’s vision defect. For example in short sight the cornea is flattened to reduce its power. The procedure is precisely controlled by a computer enabling one microscopic layer at a time to be removed. Excimer lasers have been in use for more than a decade and are generally safe and accurate. The vision correction they produce is permanent.

The excimer laser is incredibly precise as shown
in this enlarged view of an etched human hair

Worldwide, LASIK is the most widely used method of vision correction. A specially designed instrument is used to create a thin, hinged flap of corneal tissue. The flap is briefly lifted and the excimer tissue used to vaporise some of the tissue under the flap. Then the flap is replaced and heals without stitches. The procedure takes 15 minutes and requires only eye drops for anaesthesia – no injections are needed.

The advantages of LASIK are that there is no pain, good vision if often obtained within a day and the correction is stable almost immediately. LASIK is suitable for people who suffer from short or long sight or astigmatism. The range of LASIK is up to about -9 dioptres of combined short sight and astigmatism and +4 dioptres of combined long sight and astigmatism, so it may be used to treat most people (‘dioptre’ is the unit used to measure focusing error). If your prescription is outside these limits, read ‘Strong Glasses’. If you have mild-to-moderate short sight of up to about -2.5 dioptres you may wish to consider a non-laser method called ‘Intacs’. LASIK may also benefit you if you have presbyopia (dependence on reading glasses) or if you have undergone a medical procedure such as cataract surgery and are dissatisfied with the result.

As with all surgery a complication may occur but this is rare. I carry out the before-and after-care myself, not just the surgery, so these important aspects of your care are not delegated to someone else.

In LASIK a flap is made
Laser reshapes the cornea under the flap The flap is repositioned and adopts the new shape

Click here to view the video.