LASIK and Presbyopia
Laser Eye Surgery and in particular LASIK surgery, is a safe effective and predictable method of correcting nearsightedness, farsightedness and astigmatism. These common vision problems occur because the refractive power of your eyes is not accurate so as to allow light to focus at a precise point on your retina. Another type of common vision problem that is due to a deficiency in the actual focusing mechanism within your eyes is called presbyopia.
Presbyopia, which literally means "old eyes", is a normal and expected consequence of the aging process. The crystalline lens within your eyes is composed of proteins. These proteins are soft and flexible when you are younger. Beginning as you approach your 40's presbyopia occurs as the protein composition of the crystalline lens changes, making it harder and less flexible. When the crystalline lens loses its ability to flex, it is no longer able to change its shape and effectively bend light rays as sharply, and the ability to focus on near objects is diminished. As mentioned above, the clinical symptoms of presbyopia typically commence between age forty and fifty and progressively worsen through age sixty-five. When presbyopia begins, people who already wear glasses may need bifocals or trifocals, and those who have never worn glasses may require reading glasses.
If you are 40 and considering LASIK, presbyopia is an important concept to understand. LASIK has no absolutely no effect on your eye's focusing muscles or on the crystalline lens, so it does not correct ordinary presbyopia. So, if you only need eyeglasses for reading, LASIK is not a good vision correction option for you. However, if you need to have your distance vision corrected because you are nearsighted, farsighted or have astigmatism and need some help with close vision because your are beginning to experience presbyopia, LASIK may be an option if performed as a specialized monovision LASIK.
Another important consideration applies if you are mildly nearsighted and in your forties. Patients who are mildly nearsighted, perhaps less than -3.00 D of nearsighted correction, may notice that while it is not possible to read clearly or comfortably with your glasses or contact lenses on, you can read quite well by removing them. This is actually a unique advantage of mild myopia - you can be presbyopic and still be able to read by removing your eyeglasses or contact lenses. Depending on your lifestyle and daily activities, this may make you a poor candidate for LASIK. If you are mildly nearsighted, over 40 and have LASIK, in all likelihood you will achieve excellent distance vision after having LASIK, as you will become "normal sighted." This will result in your losing the ability to read since you will no longer be nearsighted. Again, depending on your individual lifestyle and vision requirements for daily living, monovision LASIK may be an option that you wish to discuss with your LASIK surgeon.