Vision Experts Don't See Eye to Eye in Quest for Perfect Sight
WebMD News Archive
Oct. 2, 2000 -- Ted Williams of the Boston Red Sox, the last Major League Baseball player to hit .400 in a season, claimed that he could see the seam on a spinning fastball as it rocketed toward the plate. So if so-called "super vision" gave the Splendid Splinter a competitive edge, could eye surgery turn a career minor leaguer into an MVP?
Maybe, but don't buy those playoff tickets just yet, say vision researchers in the current issue of the Journal of Refractive Surgery.
New technologies and surgical techniques under development may soon make it possible for a majority of even severely nearsighted or farsighted people to enjoy vision approaching or surpassing 20/20, the accepted standard of good vision.
The term 20/20 refers to the ability to see at 20 feet what most others see at the same distance. But some visually gifted people, such as Williams and Chuck Yeager, the fabled test pilot with "the Right Stuff," were reported in their heyday to have vision measuring 20/15 or 20/10. Having such super vision meant that they could see while standing 20 feet away an object that most of us could only see if we were standing 15 or 10 feet away from it.
Still, no single eye is perfect. Even people with 20/20 vision may have irregularities in the cornea, the tough transparent outer membrane that covers the pupil, or in other parts of the eye such as the natural lens (which is replaced by a clear plastic lens during cataract surgery), or the retina, the tissue covering the back of the eye on which images are formed for transmission to the brain.
The goal of corrective laser vision surgery is to make the image as it is formed on the retina as sharp and free of distortions as possible. To do this, surgeons try to correct either nearsightedness or farsightedness, as well as minor errors. "When perfected, 'ideal' corrections will provide for high contrast visual acuity between 20/8 and 20/10," writes Raymond A. Applegate, OD, PhD.
Marguerite B. McDonald, MD, clinical professor of ophthalmology at Tulane University in New Orleans, told WebMD earlier this year that if a new technology in vision correction surgery called wavefront sensing can be perfected, "we would be seeing like hawks -- not like eagles, which are 20/4, but hawks are about 20/6."
Wavefront sensing may actually soon make its way to an eye-surgery center near you. This noninvasive technology is also employed in the Keck II telescope in Hawaii. In astronomy, wavefront sensors detect the disturbances in the atmosphere that can distort telescopic images and change the shape of the telescope mirrors to correct for it.