Custom Wavefront Laser Vision Correction Technology
Most everyone who is contemplating laser eye surgery is familiar with the phoropter device to the left. It is what you look through during the sometimes frustrating test in which the doctor asks you over and over again, "Which is better, one or two?" When the test is complete, the measurements from the phoropter are recorded as your glasses prescription.
When laser vision correction first came out in the early 1990s, the only way to program the laser was to enter the patient's glasses prescription from the phoropter. Fortunately, this technique works well and millions of people around the world now enjoy clear vision from phoropter based treatments. Today, these treatments are known as conventional or standard laser treatments.
In 2003, wavefront analyzers such as the VISX WaveScan to the left became available. These instruments are low powered lasers that directly scan the eye for the needed correction, without the patient having to answer any of the sometimes frustrating "Which is better, one or two?" questions. In fact, all the patient has to do is look at a little red light and the scanner does the rest.
Wavefront analyzers are able to measure subtle forms of distortion that simply cannot be measured with the conventional phoropter. As a result, a wavefront analyzer can obtain data about the distortion in your vision that is far more precise, detailed and individualized than that obtained by the phoropter.
By programming the laser with your wavefront map, like the one below, the surgeon will provide the laser with a unique fingerprint of your vision. What's really cool is that the laser will then provide you with a unique laser treatment that matches your individual map.
When shopping for corrective eye surgery, it's critical that you understand whether your surgeon is offering you a conventional or custom (wavefront map guided) laser treatment. Custom treatments generally cost a few hundred dollars more per eye, but numerous studies have shown that they provide sharper vision that is better at night.
Currently, both conventional and custom laser treatments are still commonly performed. Patients who are more laid back and just want an affordable means of obtaining vision that will make them happy commonly consider conventional treatments. Type A personalities - those who consider their procedure a once-in-a-lifetime opportunity to obtain the best possible vision - often pay extra for a custom treatment.
Virtually all treatments can be clearly categorized as either conventional or custom. However, the Wavelight Allegretto laser from Alcon produces a treatment that contains of features of both. This treatment type is referred to as wavefront optimized.
There are four laser systems commonly used in the United States
- NIDEK EC-5000 - This laser system is only FDA approved for conventional treatments, but it is inexpensive to run and therefore a favorite of corporate discount centers. When you see an ad for super cheap LASIK, it's almost always on a NIDEK laser.
- VISX Star S4 IR - By a considerable margin, this laser system has the biggest share of the vision correction marketplace. It is capable of both conventional and wavefront guided custom treatments.
- Alcon Wavelight Allegretto - This laser system is gaining in popularity in large part due to its well-respected wavefront optimized treatment capability. It is also capable of full custom wavefront treatments.
- Bausch and Lomb Zyoptix - This laser system is rarely used in the United States, in large part because it was not FDA approved until most surgeons already had other laser systems. However, it is capable of both conventional and wavefront guided custom treatments.