LASIK eye surgery is the most common elective surgery in the US today. Presbyopia ("old eyes") is the most common vision problem, affecting everyone over age 50. However this common problem and common solution have had trouble getting together.
This type of surgery is generally meant to treat nearsightedness, farsightedness, and asytgmatism. It's most successful on people in their 20s, 30s, and 40s. By the age of 50, most people feel the effects of presbyopia, making close vision increasingly difficult, in a different way than farsightedness does. (Picture older people holding their newspapers at arm's length to try to read them.) This is presbyopia in action.) Even people who have had laser eye surgery in their youth may still need reading glasses as they age.
Monovision LASIK is currently the most-used LASIK surgery to treat presbyopia. This procedure corrects your dominant eye for distance vision and your non-dominant eye for close vision. Depending on what you're looking at, your brain decides which eye to use and ignores the (out-of-focus) input from the other eye. Many people adjust amazingly well to monovision, but it does have its downside.
With monovision, any time that truly crisp vision is required, either close or distance, you may need corrective lenses to enable you to use both eyes at once. This is particularly true in situations where depth perception (which requires both eyes) is needed.
Because of this, other procedures to correct presbyopia (known as "presby-LASIK") have been long under development. The most common approach involves cutting different angles in your cornea, so that parts of your cornea can be used for distance vision and other parts for close vision.
As technologies have improved (such as Wavefront for mapping the specifics of each patient's eyes and IntraLase for all-laser procedures) the success of presby-LASIK has increased. However, even today, the procedure is not FDA approved. The only way to have this procedure in the United States is as part of a research experiment.
Research trials have shown the procedure to be most successful in adding close vision back into the repertoire of farsighted patients. It has not been as successful at giving distance vision back to nearsighted patients, though researchers continue to see new methodologies and improved results.
More research is needed into the ideal arrangement of vision zones around the cornea. The possibility exists that no such "ideal" arrangement will be agreed upon. Instead a custom approach may ever be taken with presby-LASIK, where each person's daily priorities determine the best surgical approach for them. Patients using close vision for reading or detailed work may define close vision as their priority, while others may define distance vision as more important.
Although it is possible to find surgeons conducting presby-LASIK on patients outside the US, the procedure is generally considered "not ready for primetime." However, given the speed with which laser eye surgery techniques have improved, it may not be long before we've got a surgical option offering us through clear vision through all the decades of our lives.