The bad news is most of us will develop one or more vision problems as we age. The good news is technology is advancing to help us keep as much as we can of what we have. The Vision Council of America encourages everyone to get an eye exam every year to detect sight-threatening problems early.
As long as the retina and optic nerve remain healthy, there are many options for correcting poor vision: glasses, contact lenses, refractive keratotomy, photorefractive keratectomy (PRK), laser assisted in-situ keratomileusis (LASIK), laser assisted subepithelial keratomileusis (LASEK), Epi-LASIK, and phakic intra-ocular lenses.
LASIK is the current standard for vision correction surgery. In this procedure, a thin flap is cut from the cornea. A laser is then used to reshape the underlying tissue, then the flap is replaced as a natural bandage. LASEK is similar, but the flap is an ultra-thin layer of epithelial tissue. This gives the surgeon more corneal tissue to work with. Epi-LASIK is something of a compromise between these two techniques. Each has advantages and disadvantages; your surgeon will recommend the technique that offers the best potential for your vision.
Surgically implanted lenses are a different approach. For cataract patients, the surgeon removes the eye's natural but cloudy lens and replaces it with a synthetic lens made of plastic or silicone. For patients without cataracts, the surgeon can add a synthetic lens without removing the natural lens.
The additional lenses are called phakic lenses. For patients with high degrees of near-sightedness, laser surgery may not be able to provide enough correction, but phakic lenses still offer a possibility of complete vision correction. Currently there are 24 implantable lenses approved by the FDA.
It's common for our natural eye lenses to lose some of their flexibility with age. As a result, the range of distances over which we can focus decreases. Most of us notice difficulty in reading and other close work sometime in our 40s or 50s. A cutting edge technology for implantable lenses is the ability to accommodate to different viewing distances. One such artificial lens, called the Crystalens, has been approved by the FDA. In a clinical trial, 97 percent of patients with this lens regained 20/20 intermediate vision; 80 percent had 20/20 distance vision, and 32 percent had 20/20 near vision.
An alternative to accommodating lenses is monovision. One eye can be corrected for near vision, and the other for distance. This can be done with contact lenses or with surgery. Right now I have one pair of glasses for distance vision and another for computer work. I'm hoping for technology to produce a near-perfect accommodating artificial lens by the time I need more than this.
References:
Fong CS, “Refractive surgery: the future of perfect vision?” Singapore Med J 2007; 48(8): 709-19.
Vision Council of America:
www.checkyearly.com
FDA approved implantable lenses:
http://www.accessdata.fda.gov/scripts/cdrh/devicesatfda/index.cfm
Linda Fugate is a scientist and writer in Austin, Texas. She has a Ph.D. in Physics and an M.S. in Macromolecular Science and Engineering. Her background includes academic and industrial research in materials science. She currently writes song lyrics and health articles.