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If you have clicked on this section chances are you are one the "fortunate" that have developed the need for reading glasses. You have probably said "Why? I never needed glasses before".
 The need for reading glasses arises due to a natural aging change of the lens inside the eye, referred to as presbyopia. Most people find their arms are not long enough to see clearly to read during there 40's. We solve this easily by using brighter lighting or holding things slightly further away. It then becomes necessary to by "cheaters". At age 44 or so, one might only need magnifiers +1.25, but every few years the lens power needs to increase, to keep up with the progressive decline in close focus capability of the eyes. Then some where around age 56 or so we are wearing +2.50 power cheaters, and this is where our eyes remain for the foreseeable future.
If you look through a single lens reflex camera or camcorder, you have to rotate the barrel of the lens to adjust its focus (unless it's an auto focus camera, of course). If you focus at a distance, things close up are blurry, and vice versa. The human eye works in similar fashion. Without any effort, the normal eye sees distant objects easily. To look at something up close, focus must be adjusted; this occurs by a process called accommodation. A circular muscle behind the iris (the ciliary muscle or ciliary body) contracts and moves forward slightly. This muscle is connected to the lens by a network of tiny fibers called zonules. The change in tone and position of the ciliary muscle changes the tension of the zonules on the lens. This change in "tug" causes the lens to change its' curvature, increasing its' focusing power.
In our youth, the lens is very flexible and accommodates easily. As we mature, the lens grows in a fashion similar to the trunk of a tree. Layers of protein are deposited over time like the rings on a tree trunk, causing the lens to become thicker, denser, and less flexible. After a certain point, close focusing becomes difficult, and people need to use magnifying glasses to see near objects without eyestrain.
If you are in your mid-forties and have mild myopia (up to -3.00), you probably have discovered that it is more comfortable to focus up close and read without your distance glasses. If you have PRK or LASIK, your distance vision will be corrected, but you may find it more comfortable, or necessary, to wear reading glasses for comfort up close. This is because no type of vision correction surgery can eliminate or reverse presbyopia, which is a part of the natural aging process of the eye. Laser treatment can permanently reduce or eliminate myopia, hyperopia and astigmatism; but it cannot reverse, reduce, or eliminate presbyopia.
If both eyes are perfectly corrected for distance, one can use "drug-store type" reading glasses for close viewing. Another option is to adjust one eye to have better close focus than distance clarity. This is referred to as monovision (mono for one- one eye for distance, one for close), and is an acceptable option for many (but not all!) individuals who desire to avoid reading and distance glasses for as long as possible.
Monovision, like reading glasses and bifocals, is not a perfect solution to the optical challenges of presbyopia. It is at best a compromise. And it is not for everybody. If a group of people (all appropriate candidates with equal prescriptions) are give a chance to try monovision correction with soft contact lenses, roughly a third will like it and desire to adopt monovision. About a third will find it uncomfortable, unbalanced or otherwise unacceptable, and will prefer having both eyes corrected equally (for distance). The remaining third may grumble about monovision with the same intensity that they would lament the shortcomings of bifocals, and will be ambivalent about any long-term commitment to monovision.
Our practice now uses AcrySof ® ReSTOR® IOLs in cataract surgery. These state-of-the-art lenses are uniquely designed to improve vision at all distances - up close, far away and everything in-between - giving cataract patients their best chance ever to live free of glasses. The AcrySof® ReSTOR® IOL was designed to provide quality near to distance vision by combining the strengths of apodized diffractive and refractive technologies.
For more information on Restor® Lens, click here.
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