Conventional LASIK Laser Eye Surgery Versus Wavefront LASIK

Conventional LASIK is the traditional form of laser eye surgery, but wavefront LASIK personalizes and customizes the laser vision correction procdure to your eye. A patient from Thousand Oaks in Ventura County just asked me a good question. He wanted to know the difference between conventional LASIK and wavefront LASIK.

Both conventional LASIK and wavefront LASIK are FDA approved procedures. Conventional LASIK is how LASIK is still often done and how LASIK traditionally has been done. I’ve personally performed several thousand cases of conventional LASIK in an older era. Today, for the vast majority of cases, I consider conventional LASIK to be obsolete. Instead, I find the results to be significantly better with wavefront LASIK. Essentially, with a very few special and rare exceptions, wavefront laser eye surgery is all I do in my own practice.

Conventional LASIK is based on the philosophy of using the laser to etch your glasses or contact lens prescription directly into your eye so that it is as if you are constantly looking through your contacts. This prescription, in turn, is based entirely on your answers to the refraction — the “which is better one or two test.” This test, however, is not very accurate. First, it is subjective. Many patients become nervous when asked to pick between “one and two” because it often is difficult to make a choice! Literally, you could answer “number one” on one day and “number two” on the next day, even though your eye didn’t change. In this way, this test is not very accurate.

The refraction test is inaccurate for other reasons too. Each “click” is 0.25 diopters, meaning you could actually be between clicks. Furthermore, each lens that is presented to you to choose from is a standardized lens. These are the same lenses that will be used to test the next patient and the one after that. Because they are standardized, they have a uniformly curved, “one size fits all” configuration. It turns out, though, that nobody’s eye is perfectly uniform. The top of your pupil actually will have a slightly different micro-prescription than the middle or the bottom or the side. For this reason, a truly uniform, standardized lens will not be able to correct all the different micro-requirements over your entire pupil. At best, a comprimise correction that more or less corrects everything will be the best you could hope for.

By contrast, wavefront LASIK uses a different method to measure the eye. With wavefront, an infra-red laser beam is shined into your eye and its reflection is bounced off the back of your eye in a process called the “WaveScan” of your eye. The reflected laser comes back as a returning sheet — or wave — of light. We measure how the front of the returning wave, the “wavefront,” is distorted as light flows through your eye. We map the three dimensionally complex distortions in the wavefront of light as it emerges from your eye. We call this map your “optical fingerprint” and it tells us how light is affected by its journey through your eye. It is a unique-to-you personalized measurement. In the case of wavefront LASIK, we download your optical fingerprint to the laser and reproduce its customized correction directly onto your eye with billionth of an inch tolerances — even on a moving target!

In this way, you can see why wavefront LASIK is more accurate than conventional LASIK. Wavefront LASIK personalizes the treatment specifically to your eye by treating your objectively measured optical fingerprint. By comparison, conventional LASIK is based on your selectively chosen uniformly curved standardized lens correction and is not customized specifically to your eye.

There are various names for wavefront LASIK. Wavefront LASIK is sometimes called “Customized Wavefront” LASIK or “Wavefront Guided” LASIK. CustomVue LASIK is the proprietary name for wavefront LASIK used by VISX, the manufacturer of the laser I prefer and use. Other proprietary names for wavefront LASIK from other laser manufacturers include CustomCornea LASIK, WaveLight Wavefront Guided LASIK, and Technolas Zyoptix Wavefront Guided LASIK.

Conventional LASIK Laser Eye Surgery Versus Wavefront LASIK

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