With LASIK eye surgery or PRK, the laser basically sculpts a new, precise shape, or curvature, to your cornea, by energizing and lifting off discrete layers of corneal tissue. It converts solid material into gas. This is permanent.
However, consider it a permanent difference from your underlying prescription. Fluctuations in your underlying prescription that otherwise would have occurred will still occur. For instance, as one gets over 45 years old, age-related loss of near vision continues. The LASIK effect remains just as good for distance but reading glasses may be necessitated.
What happens to your eyes as you age
Myopia and astigmatism often develop in your teenage years, as your eye elongates, but levels off. This is why we wait until your refraction stabilizes before treatment.
Like all cameras, focus is dependent upon the dimensions of the eye and the properties of the natural lens. There are periods of your life in which the dimensions are more likely to change. Myopia and astigmatism often develop in your teenage years, as your eye elongates, but levels off. This is why we wait until your refraction stabilizes before treatment.
Why you may need reading glasses after age 40
Below age 40, while wearing distance correction, you can also read as the muscles in your eyes can flex the internal natural lens to refocus up close in a process called “accommodation”. In the early 40s, your lens hardens and loses flexibility. It’s sort of like your auto-focus camera getting stuck at distance. This is called presbyopia. This continues to worsen until age 65, when there is no accommodation.
Hyperopia or far-sightedness occurs because you have a relatively short eyeball. If you have this, you can often compensate by using your accommodation ability. But as you age, since you’ve consumed part of your accommodation ability just to see at distance, you have less left over to use for reading. You become more dependent on reading glasses quicker than others. Soon, you need glasses for distance and near. Physics is funny. Your focal point is behind your head!
At your consultation, the surgeon needs to hear your main goals and concerns and address them as best as humanly possible. The refractive or focusing goals vary with your needs, hobbies, vocation and more.
Option 1: Having both eyes set for distance
If you are less than 40 years old, the goal is often both eyes at distance. Because you still have accommodative ability, you will be able to see both far and near. However, if you are over 40, you have two major choices. If you choose to have both eyes set for distance, you will need reading glasses, increasingly so as you get older. This is the same as if you had contact lenses. If you’re a spectacle-wearer, you’d be getting bifocals. This choice is appropriate for someone who drives a lot, or a high-level athlete in which binocularity at distance is important.
Option 2: The “blended vision” option
Another choice is to have “blended vision.” In this scenario, one eye is treated for distance while the other is left a little near-sighted. The key is to keep the differential small enough that you don’t feel off-balanced for the most part. Doing this will delay your need for reading glasses and when you start to require them, they are used much less frequently.
The blended slightly near-sighted eye will always maintain “casual near ability.” This proves very helpful, especially when you’re “on the go.” You can see your cell phone, a price tag, the dashboard, your food while eating, etc. Most people don’t mind reading glasses when you’re at your desk or reading long-term. These are predictable locations where you leave OTC readers. You might need distance glasses for very detailed situations such as driving at night.
All said, this choice is for the person who says he/she wants the overall least dependence on glasses for as long as possible. Indeed, the sculpting of your cornea by the laser for LASIK or PRK is permanent. But keep in mind your eyes and needs change throughout life. The bulk effect of LASIK puts you in the right ballpark for life. The smaller variations inherent in biology will carry-on.