The lasers that are used in Lasik eye surgery are truly unique and use exceptional technology. Excimer lasers were created specifically for Lasik. The FDA has approved each type of laser, but some lasers are better than others. The biggest difference is the way that the beam is delivered to the eye and their ability to track eye movement.
There are two broad categories of laser including broad beam and scanning. There are two categories within scanning lasers including slit scanning and spot scanning.
Broad Beam Lasers
Broad beam lasers utilize a large beam diameter, ranging from 6 to 8 millimeters, that cut the cornea. The use of these lasers shortens the amount of time that is necessary to complete the surgery. These lasers also reduce the risk of over correction due to pupil movement. The larger diameter makes the likelihood of complications more likely, but improved technique has eliminated most of this risk.
Slit Scanning Lasers
Slit scanning lasers use smaller beams. The beam is linked to a rotational device that has slit holes to enlarge the area that is being cut. Slit scanning lasers provide a more uniform beam and creates a smoother cut. There is a slightly greater chance of over correction with these lasers.
Spot Scanning Lasers
Spot scanning lasers are referred to as “flying spot” lasers. These use a small beam of 0.8 to 2 millimeters. The beam is scanned across the cornea in order to create the area to be cut. Spot scanning lasers have potential to create the smoothes cut. They are also able to produce customized cuts and are able to treat irregular astigmatism.