The Lasik surgery procedure doesn’t take much time, just a few minutes in fact, and it can be used to help people who suffer from nearsightedness, farsightedness or astigmatism.
A traditional instrument used in Lasik is called a “microkeratome”, and what is does is create a very thin circular flap in the cornea. Nowadays, this step is performed by using a laser instead (thus the term laser surgery). In the next stage of the procedure, the surgeon will fold the flap back and remove some tissues of the cornea underneath this flap using an excimer laser. The excimer laser removes a very thin layer of the corneal tissue to reshape the cornea, by producing a cool ultraviolet light beam.
A computer will already have determined the amount of layers to be removed from the cornea, and this level is calculated from the required focus of the light through the eye and onto the retina, to achieve the required vision. The operation is concluded by the surgeon flipping the flap backwards in its previous place, covering the area of the layers of corneal tissue now removed. The changes made to the cornea will depend on the problem being addressed. For nearsighted people the target is to flatten the too-steep cornea, while for the farsighted people the target is logically the exact opposite – to steeper the cornea. When correcting astigmatism the surgeon will smoothen the irregular cornea into a normal shape.
As there are some cases where it might be risky or even impossible to undergo the Lasik surgery procedure, the patient will have an examination for the eyes before the surgery – in order to determine their health and the possibility of moving on to the surgery. Part of the examination have the ophthalmologist using a slit lamp (or refractor) to examine the retinal problems. He also uses a tonometer in to determine the intraocular pressure. Too high pressure for example, may be indicative of glaucoma (damage to the optic nerve).
Another part of the pre-surgery examination is the hydration of the eye, to rule out any dry eye disease. Because this type of disease needs to be solved before the Lasik can be performed. A corneal topographer is then used to photograph the eye, creating kind of a map of the cornea. Nobody has a perfectly rounded cornea – the task of the topographer is to reveal the corneal irregularities, such as steepness or flatness, which the surgeon will rectify during the surgery. As the technology has evolved, there are a new technique for this stage as well. These are referred to as “wave front devices”, and they work by sending waves through the eye to in order to give a more precise map of the corneal irregularities that affect your vision.
Before the procedure, the surgeon should also ask questions about your general health, as specific health problems or taking certain medications may affect the surgery, or result in other dangers to your overall health. If you are aware of any special health condition, you should inform your doctor about it openly, and he can then determine whether it is safe to undergo this operation, or if it would be better to wait or call the whole thing off.
By reading basic information on the Lasik surgery procedure, you can get a pretty good picture if you an go through with the surgery. However, the decision will always be approved and finalized by a doctor.