Laser eye surgery is undertaken to permanently change the shape of the cornea and the lens of the eyes. This is necessary to correct vision problems like short-sightedness, long-sightedness and astigmatism to eliminate the need of wearing glasses or contact lenses. Generally, it is an out-patient procedure which takes about an hour. As simple as it may sound, people are often wary about the safety of laser eye surgery as it involves a very important body organ. Before undergoing this procedure, it’s best that you know some basic facts.
Here are some common types of laser eye surgery:
• Photorefractive Keratectomy (PRK). The outer layer of the cornea (epithelium) is removed with a blunt instrument like a surgical blade. A computer-guided laser beam vaporizes tiny amounts of tissue under the surface of the cornea. Sufficient amount of tissue is removed to reshape the cornea to correct vision. Because the eye can be very painful after PRK, painkillers and a bandage contact lens is fitted with antibiotics and anti-inflammatories. Healing time: one week.
• Laser Assisted in situ Keratomileusis (LASIK). A flap in the cornea will be cut with a sharp blade or laser. The flap will be lifted and a computer-guided laser will remove calculated amounts of tissue from the inside layers of the cornea. Flap will be put back afterwards. While more complicated than a PRK, eyes heal faster with the LASIK. A more advanced option, Wavefront technology, may be explored as it corrects vision more precisely. It is common to have 20/20 vision the day after a LASIK procedure.
• Laser Epithelial Keratomileusis (LASEK). The epithelium is cut with a fine blade and alcohol is used to loosen and lift it in a single layer. Laser beam is directed at the tissue under the epithelium. Afterwards, the epithelium is put back in place. This is advisable for vision problems that require minor correction. Healing time: two weeks.
• Epi-LASIK. In this modification of the LASEK, the epithelium is removed with a mechanical device using a blunt instead of a sharp blade.
It is important to bear in mind the following precautions when undergoing laser eye surgery:
• Eye patch will be worn over the treated eye for 24 hours.
• For the first three months, tinted glasses with ultraviolet protection should be worn when out in the sun.
• It should be performed by a qualified ophthalmic surgeon with training in laser eye surgery.
Laser eye surgery is a relatively safe procedure with complications occurring in less than five percent of cases. Moderate to severe pain may be felt in the first few days after the surgery. This is usually not the case with LASIK but with the other procedures. Here are some of the rare complications that may occur:
• Regression of the vision problem in which case a second surgery may be needed.
• Dry eyes in the months after the surgery. This may be addressed by using artificial tear supplements. In some cases it can linger and be quite a nuisance. It is best to treat any dry eye aggressively before the procedure if possible.
• Glare or halo effects during night driving, especially right after treatment and when higher correction is done. Thus, driving is not advisable within one to two weeks after the surgery.
• Unstable eye shape due to excessive thinning of the eye wall.
• Very rarely, severe vision loss occurs which require corneal surgery or use of hard contact lenses to restore vision.
Before undergoing this procedure, it is best to consult your optometrist that understands the idiosyncrasies of your eyes to know whether or not you would be suitable for a laser eye surgery. To be assessed properly you will need a corneal topography (geographical map of the cornea) and a global pachymetry reading (corneal thickness measurements at many points) to be sure your cornea is not too thin for the procedure.