Presbyopia is an eye condition which affects all individuals. Typically, once a person is beyond age 40, they start loosing the ability to see near objects well. For someone who has no refractive error for distance (i.e., wears no glasses or contact lenses to see clearly at distant objects), nearby objects become blurred. This is typically manifested by not able to read the text of a book, or a mobile phone. Initially, one can compensate a bit for this by holding objects at arms length, rather than at more normal distance (about a foot away from the eye). But eventually, the person needs to wear +ve power spectacles for seeing near objects or while reading. The amount of +ve power increases from about +0.5 at the age of 40 to about +2.5 at the age of 60. Since it is often inconvenient to whip out a pair of spectacles everytime one wants to read something, people often wear bifocals.
Even people with a error for distance would face this problem. For myopic individuals (those who have a -ve spectacle power), this problem is most times resolved by removing spectacles to see nearby objects or while reading. But eventually, everyone needs to wear reading glasses or bifocal glasses or progressive glasses to deal with the problem of aging eyes or presbyopia.
Typically, when you undergo refractive surgery (i.e. LASIK), you get corrected for your distance vision. Once you approach the age of 40, or if you are older than 40, it is important to realize that you too would need reading glasses, even if you have undergone LASIK.
New technology, however, allows a reasonable solution to this problem, even if you are over 40. Before the new technology of Laser Blended Vision, for persons with age 40 or more, we would keep some amount of myopia in one eye, and correct the other eye perfectly for distance. The myopic eye would work well for near vision, while the perfectly corrected eye would work for distance vision. Between both eyes, many patients could do all their distance and near work reasonably, needing to wear glasses only occassionally. This solution is called monovision. Most people who undergo monovision are happy. Sometimes, the two eyes do not blend well together, and they do not see intermediate objects well.
With Laser Blended Vision, we use a special laser reshaping profile, which increases the depth of focus in both eyes. In addition to this special profile, we also induce monovision, as above. The near eye then sees better for distance then it would otherwise, and the distance eye sees better for near than it would otherwise. This is because of the special profile which increases the depth of focus. In the intermediate, the two eyes blend well, and the patient gets good near, intermediate, and distance vision. Inevitably, there is some compromise, but this compromise is acceptable to most patients. This is perhaps the best solution that is available for aging eyes at the moment.
Dr. Rupal Shah has extremely high amount of experience with this new method, as well as with monovision. Hundreds of people have undergone LASIK after the age of 40 with her, and they are amongst her most happy patients. Indeed, she has also treated her husband with the same technique of laser blended vision.