The EX 500 fires at 500 times per second. “So what?” you ask. It matters so much as during the laser treatment, the cornea stars to dry out. A dry cornea absorbs more laser energy. If the treatment is completed before the drying really sets in, the results are more predictable. The Wavelight laser treats 1.4 diopters of prescriptive error per second!
Laser vision correction reshapes your cornea by gently vaporizing away the parts of the cornea that make your vision out of focus. The best way to increase LASIK safety is to prevent complications. Prior to surgery, we measure the thickness of your cornea to make sure your cornea is thick enough.
The goal is to leave enough cornea untouched so it will remain stable throughout the rest of your life. Many surgeons feel the magic number is 300 microns. We want to leave at least 300 microns untouched to create an extra margin of safety.
Here’s an example. If your cornea is 540 microns thick and your surgeon is planning a 110 micron thick flap with a laser treatment that will vaporizes away 100 microns, the residual bed of untouched cornea would be 320 microns. (520-110-100=310). This would meet this criterion for surgery.
Sounds great, but what if the flap is thicker than expected? (This is rare) Let’s say the flap was actually 220 microns thick. (520-220-80=240) This is well past the safety goal of 300 microns.
Most surgeons do not measure the thickness of the flap or the residual bed before they treat. I have never been comfortable with this so I have always paused to actually measure the thickness manually with a pachymeter before I treat, just in case the flap is thicker.
The Wavelight EX 500 Excimer Laser has a built in OCT imaging systems that measures the corneal thickness automatically before I treat. The measurement is displayed through the microscope ocular while I am looking at your eye. This is an important LASIK safety advance.
Many patients worry that they will move their eye during the laser treatment. The fact is that you will move your eye during the procedure, but the good news is that the Allegretto laser tracks the movement of your eye and adjusts the treatment accordingly. The EX 500 tracker is checking the eye position 1050 times per second with just a 2 millisecond latency! This is an important improvement for accuracy and safety. In addition, there is a display inside my ocular that shows me the quality of the tracker acquisition. This helps me ensure the tracker is fully engaged before I treat and during the treatment.
The laser displays your vital data in my microscope oculars during your treatment. I can see your name, date of birth, planned treatment, and a count down of the treatment completed during your laser. This gives additional confirmation safety that the correct patterns for your specific visual needs are programed and completed.
The laser beam is created in the main cavity of the laser. It then travels approximately three feet through the laser arm where it is directed towards your eye. The atmosphere causes small changes in the quality of the beam. In some other Laser systems, the beam passes through the atmosphere for the entire length of the laser arm. In the Wavelight laser system, the beam is sealed and protected from the atmosphere by nitrogen gas in the laser arm.
The Alcon EX 500 Laser uses a small-spot laser beam, which allows LASIK specialists to shape the cornea in finer, more gradual increments for a smoother surface with eye-tracking technology 8 times faster than some of the competition.
The Alcon EX 500 Laser’s integrated cross-line projector provides the surgeon with an exact alignment of the head’s and eye’s position by generating a red-light cross on the eye for accuracy.
Using advanced Wavefront Optimized ® technology, the Alcon EX 500 Laser creates a “map” of your eyes and their unique characteristics to assist your surgeon in creating a personal vision profile for you. This map is created preoperatively on the OCULYZER and the data is transferred to the Laser machine via an internal LAN and serves as a guide that helps us locate the eye’s exact treatment position, which is one of the most important factors in obtaining a more naturally shaped cornea and therefore an excellent refractive outcome, especially when correcting eyes with high astigmatism.Oculyzer
WaveLightOculyzer is the most advanced diagnostic device for corneal tomography (topography). It helps us to obtain much information about the cornea, the part of the eye where the laser vision correction is undertaken. Oculyzer is an invaluable tool in refractive surgery procedures such as LASIK.
The system is based on the proven Pentacam technology that uses a rotating three-dimensional Schleimpflug camera for detailed imaging of the cornea and anterior segment of the entire eye.
Oculyzer allows very precise measurements of the complete front and back surfaces of the cornea, the thickness of different points of the cornea is extremely important for the safe performance of refractive surgery.
Oculyzer is optimized to work with the WaveLight EX 500 Hz laser system which enables topographically controlled individual treatments. The data about the patient's cornea obtained with Oculyzer are inserted into the laser. Based on them the laser is programmed. This enables correction of possible individual irregularities of the cornea what is important not only for the elimination of diopter, but for the better vision quality also. Because of that, this is a solution for many cases where wavefront guided and standard ablations are not enough.
Another very important function of WaveLightOculyzer is the possibility of early detection and precise grading of Keratoconus enabling timely and appropriate treatment.