LASIK, which stands for Laser Assisted In Situ Keratomileusis, is a surgical technique for performing laser eye surgery. LASIK surgery is recommended for people who are short-sighted or have astigmatism, as well as some types of long-sightedness.
If you have poor vision the idea of life without spectacles or contact lenses is very appealing. Contact lens wearers have to clean and replace their lenses regularly, and face the risk of a lens becoming dislodged, or worse, infecting the eye by introducing or trapping bacteria underneath them. Meanwhile, people who wear glasses must constantly care for and clean them, and can sometimes feel self-conscious about having to wear them. They can also be very expensive to repair or replace if lost or broken.
In both cases, finding a permanent solution for clear vision is a quality of life issue; one that millions of people are discovering every year.
The history of LASIK
The LASIK technique was made possible by a Spanish ophthalmologist in the 1950s, who created the first microkeratome. This tiny precision blade is used to cut thin flaps in the cornea and change its shape in order to affect the way light is refracted through the eye.
Then, during the 1970s, a second milestone was crossed with the development of the Excimer laser. This argon-fluoride gas laser works by emitting computer-controlled pulses of ultraviolet light to break molecular bonds. This means it can remove as little as 1/40th of a cell without damaging any of the surrounding cells, forming the cornerstone of all laser eye surgery techniques.
The first LASIK procedure in the UK was carried out in 1995, and since then there have been dramatic improvements in laser speeds, incision techniques, and computer-guided technology. While other techniques have evolved, such as Epithelial LASIK, PRK, and LASEK, the original form of laser eye surgery is LASIK, and it remains the most popular and comfortable choice for patients today.
Candidates for LASIK
Candidates for LASIK surgery must be over 18 and have stable vision, meaning your prescription hasn’t changed for at least a year. LASIK is suitable for most cases of:
Myopia (short-sightedness) – by flattening the cornea
Hyperopia (long-sightedness) – by steepening the cornea
Astigmatism – by smoothing the cornea into a regular shape
However, LASIK can’t improve prebyopia (long-sightedness due to ageing) as this affects the inner lens of the eye and not the cornea. LASIK is not recommended if you have a condition that makes healing difficult, such as rheumatoid arthritis.
The LASIK procedure
After an initial consultation you will be given a date for your LASIK laser eye surgery. It is possible to have both eyes treated on the same day, or you can allow a short recovery period after the first eye. At less than 30 minutes, LASIK is performed on an out-patient basis so you can return home from surgery on the same day.
Lying back in a reclining chair, the surgeon will clean your eye and administer anaesthetic drops. A lid speculum will be fitted over your eyelids to gently hold them open during the operation. Next, a special ring will be attached to the surface of your eyeball and suction will form around the cornea, causing the vision to blur and dim.
Using a precision blade, the surgeon will cut a small flap in the outer layer of the cornea, known as the epithelium. This flap will be folded out of the way, and you will be asked to focus on a light. Meanwhile, a second light – the computer-guided laser – will begin pulsing and reshaping the middle part of the cornea (known as the stroma).
During this brief process you will hear a loud ticking noise (the sound of the laser pulsing) and you may smell burning (as the corneal tissue is removed). This is perfectly normal. Once the cornea is reshaped, light entering the eye will be refracted differently, resulting in a clear image landing on the back of the eye (known as the retina). The cornea flap will be precisely replaced and covered with a protective shield to reduce irritation.
Afterwards, you shouldn’t feel any pain although your eye may feel uncomfortable for a few hours. Your vision may be blurred for the next day or two but will fully stabilise over the next four weeks. Eye drops will help prevent infection, and sunglasses should be worn outdoors to protect the vulnerable eye from UV rays.
This article is written by Jackie Griffiths, a freelance journalist who writes health, medical, biological, and pharmaceutical articles for national and international journals, newsletters and web sites
Last Editorial Review: 3/6/2010