The most exciting news in laser vision correction in the past five years has occurred with the Food and Drug Administration’s approval of VISX’s Custom Vue TM wavefront-guided treatment for patients with nearsightedness and/or astigmatism.
A sophisticated piece of diagnostic equipment called the WaveScan identifies and measures imperfections in an individual’s eye 25 times more precisely than previous methods. WaveScan permits LASIK surgeons such as me to analyze a person’s entire visual system, not just the shape of the cornea.
With the FDA’s approval, this WaveScan data - which is contained in a report called the WavePrint -- can now be transferred to the VISX Star S4 laser for custom wavefront-guided LASIK to provide a new level of accuracy and precision. Studies show the possibility will now exist for individuals to see better than 20/20 after LASIK surgery.
FDA clinical study data presented at the 2003 American Society of Cataract and Refractive Surgeons (ACRS) which I attended recently revealed that one year following wavefront LASIK, 94% of the study participants could see 20/20 or better; 74% could see 20/16 or better, and 27% could see 20/12.5 or better. Also, nearly 70 percent had either the same or better post-op vision contacts than their best visual acuity with glasses or contacts. Additionally, four times as many participants were very satisfied with their night vision compared to their night vision with glasses or contacts. In the past, 20/20 was considered the benchmark of good vision.
Before wavefront-guided, LASIK surgeons relied on "sphere" and "cylinder" to describe vision correction issues affecting focus and astigmatism. These lower order aberrations will still be measured by the WaveScan diagnostic device. These measurements of sphere and cylinder are similar to measurements made during a conventional eye exam, called a manifest refraction, but are more precise.
Lower order aberrations are still the greatest contributors to refractive errors of how light passes through the cornea (Nearsightedness, farsightedness and astigmatism are refractive errors). Also, lower order aberrations are generally more significant in their impact on your vision than higher order aberrations.
With the new WaveScan, higher order aberrations are identified. These higher order aberrations are different than sphere and cylinder, but have a noticeable impact on vision.
The WaveScan produces test results called a "waveprint" which provides surgeons with all of the aforementioned data, which in turn are programmed into a custom treatment plan utilizing the VISX Star S4 laser.
Conventional laser vision correction before wavefront corrected sphere and cylinder errors. The precision was limited by information provided by the phoropter (the adjustable machine in most eye doctor offices) used to measure the best spectacle (eyeglass) correction. This precision was limited to 0.25 diopter steps. With WaveScan, sphere and cylinder are measured to the hundredths of a diopter.
Technically, no two individual’s eyes are exactly alike. However, using phoropter measurements, thousands of individuals can have the same prescription. The WaveScan’s "fingerprint" of the eye that is unique to the individual. Therefore, wavefront-guided LASIK will be designed specifically for each patient’s eyes.
Just as when LASIK was first approved in 1995, this new approval is for nearsighted individuals. Nearsighted individuals with up -6 with astigmatism between 0.00 and -3 diopters will qualify.
Wavefront candidacy will still be guided by physician review and interpretation of one’s higher order aberrations. Prevailing wisdom is patients with higher order aberrations that make up 20% of the total aberrations of the eye make better custom wavefront-guided LASIK patients. Normal LASIK candidacy criteria will continue to apply. These include being 21 years or older, having a stable prescription for at least a year and other medical conditions (see our website at www.doctorwhitsett.com).
In addition to the results of the wavefront LASIK studies which were conducted at various sites throughout the United States the past year, the new wavefront procedure provides unparalleled safety. The VISX Star S4 laser is the already the most used by LASIK surgeons in America. Its sophisticated three-dimensional eye tracking capability helps makes sure the prescribed treatment occurs as planned, instead of being altered slightly by inadvertent eye movements.
Because Wavefront LASIK utilizes the same surgical process as traditional LASIK, you can have the reassurance of the fact more than several million LASIK surgeries have been performed successfully.
IF YOU WOULD LIKE YOUR QUESTIONS ANSWERED PERSONALLY
If you would like to learn more about the aforementioned or to email questions, visit our website at www.doctorwhitsett.com. Or better yet, call Michelle, our laser vision coordinator, at 713-365-9799 to set a time for your free consultation. During that consultation, I will meet personally with you and answer your concerns one-to-one.
Dr. Jeffrey C. Whitsett 
Jeffrey C. Whitsett, M.D., has twice been named a VISX Star surgeon, an honor bestowed on the top 100 providers of Laser Vision Correction in the United States. Presently, he serves as president of the Eye Laser Center of Houston. A 1986 graduate of the University of Oklahoma Medical School, he has been in private practice for more than a decade specializing in refractive and cataract surgery.
Dr. Whitsett is Board Certified by the American Board of Ophthalmology and the Texas State Board of Medical Examiners. He is involved in several major national and international ophthalmology organizations, and lectures nationally for Alcon Surgical about the most current concepts in cataract and refractive surgery.
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