LASEK, which stands for Laser Assisted Sub-Epithelial Keratomileusis, is the latest technique for performing laser eye surgery.
LASEK eye surgery is suitable for people who can’t have the traditional LASIK surgery because the clear outer lens of their eye, the cornea, is too thin or too flat. It is also recommended for people who shouldn’t have a flap cut into their cornea because of their occupation – such as pilots or athletes.
This article on LASEK eye surgery 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.
Candidates for LASEK
Choosing LASEK over LASIK is likely to be determined by practical reasons, for instance, if your cornea is already very thin from having previous LASIK surgery. Your consultant will let you know if LASEK is the best option for you.
To have LASEK, you must be over 18 and have stable vision, which means your prescription hasn’t changed for at least a year. It can be used to treat 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
The LASEK procedure
The technique for performing LASEK eye laser surgery differs slightly from that of LASIK.
To begin, anaesthetic drops are put in the eye and a lid speculum is attached to the eyelids to gently hold them open throughout the procedure. This is standard for all types of laser eye surgery.
During the LASEK procedure, a pre-incision is made in the outer layer of the cornea (the epithelium). A tiny cone is placed on the surface of the cornea and a mild alcohol solution is dropped into the cone and left for half a minute. The area is then rinsed thoroughly and the newly-softened epithelium is lifted and rolled to the side to expose the middle cornea layers (known as the stroma). With this method there is no need to cut the cornea with a blade, so the cornea flap never becomes completely detached. This enables it to be folded back into place with utmost precision.
As with all other laser eye surgeries, the next stage involves a computer-guided laser, known as an Excimer laser, sending pulses of UV light into the eye. This breaks down a microscopic amount of the cornea in a precisely controlled way. The process takes about 30 seconds, during which time you will hear the loud ticking noise of the laser, and possibly smell burning as the stroma is reshaped. Your vision may be temporarily blurry or dimmed.
Afterwards, the cornea flap will be replaced and a soft contact lens will be put in to protect the eye during the initial healing period. The majority of patients have both eyes treated at the same time, so there will only be one recovery period during which you won’t be able to drive, or go to work.
Pros and cons of LASEK
While all laser eye surgeries carry similar risks associated with lasers, healing, and success rates, the technical variations between LASEK, LASIK, and PRK all involve the preparation of the cornea. The way in which the epithelium is folded, cut, or scraped away affects the level of post-operative discomfort and healing rates.
LASEK vs LASIK: The main benefit of LASEK eye laser surgery is that no cut is made in the cornea. This eliminates certain risks associated with LASIK, such as the use of a microkeratome blade and the accurate repositioning of the cornea flap. However, since LASIK boasts a more comfortable and shorter recovery period, the majority (over 85%) of laser eye surgeries are carried out using the LASIK technique.
LASEK vs PRK: In comparison to PRK, which involves scraping away the outer cornea and allowing it to grow back naturally, LASEK has a much more comfortable recovery period which lasts 1-2 days. After PRK, it can take the epithelium around 3-5 days to grow back, accompanied by slightly greater discomfort and blurred vision. LASEK also carries less risk of infection because the stroma is not left exposed for longer than a few minutes.