LASIK stands for laser-assisted in-situ keratomileusis, and it refers to a type of refractive eye surgery that treats conditions like near sightedness, far sightedness and astigmatism. LASIK doctors use refractive surgery to change the shape of your cornea – that is, the clear dome on the front of your eye – in order to focus the light rays on your retina more accurately. For many people, this can result in a new freedom from using glasses or contact lenses.
There are two major types of higher energy lasers used by LASIK doctors – excimer lasers and femtosecond lasers. Excimer lasers work by producing ultraviolet light on a specific wavelength – usually 193 nanometers – which is absorbed by the tissue, meaning that tissue can be removed, or ablated, from the underlying stromal area of the cornea without damaging surrounding tissue. The amounts that can be removed this way are microscopic – as small as 0.25 microns of tissue, one micron being one-thousandth of a millimeter.
Most modern types of excimer lasers use automated eye-tracking systems to monitor eye movements during surgery and keep the ultraviolet beam on target. Different types of excimer lasers use different patterns for tracking the eye and delivering the beam. Two of the main types are spot scanning and slit scanning lasers.
Slit scanning lasers use small beams that link to a rotating device with slit-shaped holes. As these holes enlarge, the beam provides a gradually expanding ablation zone. Spot scanning, or flying-spot, lasers use tiny beams of less than 2 mm, which can be scanned across the cornea to identify the ablation zone. These are the most common type, and provide the smoothest treatments.
The most advanced excimer lasers used by LASIK doctors are wavefront-guided lasers, which use innovative technology to detect and correct corneal flaws not picked up by other systems. The procedure is guided by a detailed wavefront map of your eye, which enables the treatment to be completely customized and personalized, and unique to each patient. These lasers also usually result in clearer, sharper vision, with greater contrast sensitivity.
Instead of excimer lasers, some LASIK doctors Houston patients may see will choose to use femtosecond lasers, which are ultra-fast, ultra-short pulse lasers. These are generally used in the type of LASIK surgery called iLASIK. This combines wavefront technology with a procedure called IntraLase, to produce an exceptionally precise type of laser surgery.
IntraLase is used in the first stage of LASIK surgery, which is the creation of a thin flap of tissue that is folded back to allow treatment. Instead of using a blade or microkeratome to create this flap, IntraLase uses a femtosecond laser, which produces an infrared beam of light to create the flap from the inside of the cornea. This is considered by most surgeons to be much safer than using a blade, and to provide a much more precise and accurate flap.
Many LASIK doctors achieve excellent outcomes by using femtosecond and excimer lasers in combination. There are a number of laser systems of both types on the market, and which is best for you will depend on your specific requirements, such as your pupil size, and your degree of refractive error. However, while specific laser technology has a key role to play, the major factor affecting the outcome will be your surgeon’s skill and expertise. That’s why you should see Dr. Goosey, the LASIK doctor Houston doctors trust with their friends and family. Find out if LASIK is right for you, and contact us to schedule your free LASIK consultation.