Many men and women resist buying their first pair of reading glasses. To them, reading glasses—no matter how stylish—are irrefutable proof that the aging process is marching on. Fortunately, new alternatives are available to those who don't like the thought of fishing glasses out of their bag or their pocket each time they need to read a menu.
Below, Penny A. Asbell, MD, a professor of ophthalmology at Mount Sinai School of Medicine in New York, discusses why people lose their ability to read close-up—a condition called presbyopia—and reviews their vision options.
Why does our vision change as we age?
Inside the eye is a lens, and that lens actually changes shape. When we are young and we're looking into the distance and then close-up, the lens changes shape so that we can focus and continue to have good vision. What happens as we age is that lens gets a little stiffer, and it doesn't change shape as easily. That is when you start reaching for reading glasses, because you need the extra power that your own lens can't provide anymore. We call that presbyopia, when you can no longer see close-up.
Who ends up needing reading glasses?
Everybody ends up needing reading glasses. This is universal. There are people who had great vision their whole life. They said, "I'm eagle eyes. I can see everything far away." Now they're in their 40s, and they're having trouble reading, and it's really disturbing to them.
When does presbyopia begin?
Typically, you first become symptomatic in your 40s, requiring a low-plus lens, usually a +1. And then it moves up to about a +3. So as we age we end up needing a little bit more over time.
What kind of glasses are available?
They now sell reading glasses in the drugstore. Those work fine for many people. And for people who already need corrective lens for distance, there are glasses called progressives that have a different power on the top for distance, and the bottom power has reading power. They look like normal glasses, but they actually give you good distance vision and good reading vision. Bifocals are the glasses where you actually can see the line in the glass. Those work terrifically but in our youth-oriented culture, people don't like to wear glasses that make them look old, so to speak.
And now there are contact lenses that act like bifocals that give you distance and near vision, and some patients do very well with those.
What is monovision?
Monovision is where you correct one eye for distance and the other eye for reading. Sometimes they call it blended vision because you actually continue to use both eyes together. It is just that one eye is doing more of the distance vision, the other one is doing more of the reading vision.
This is something we have done for many years with contact lenses. You cannot do it with glasses. It's just creates an unbalanced feeling if you have one glass that is good for distance and one good for reading. But we can also create monovision with surgical procedures, such as conductive keratoplasty (CK) and laser surgery.
Does monovision work for everyone?
Monovision works very well for many people. However, in some people, they may feel a little unbalanced or even have a change in their depth perception. So if somebody is thinking of monovision, whether it's with contact lenses or refractive surgery, the best way to decide whether it is for you is to try it with contact lenses first.
What does the laser surgery involve?
Laser surgery, such as LASIK, has now been around for more than 10 years. When we use a laser, we change the shape small part of the cornea. If we change the shape of the cornea, we can change the vision. The laser is used to cut and remove tissue, so there is a permanent change to the eye.
What is conductive keratoplasty (CK)?
In CK, we use a tiny probe that delivers radiofrequency energy to the part of the cornea called the stroma, and it shrinks that tissue, kind of like cinching a belt, to tighten the cornea and make the central part steeper. CK has become an exciting alternative for people who are presbyopic. It is minimally invasive. There is no laser. There's no cutting. There's no tissue removed. And the chances are you'll have excellent vision.
Are there people who are not good candidates for these surgeries?
If you come into laser surgery with significant dry eyes, they may get worse after the laser procedure. Sometimes patients may experience a glare or halo after the procedure, especially when driving a car.
When assessing people for either surgery, one of the things I like to find out from patients is what kind of work they do. If it's somebody who's cutting diamonds, these surgeries may not be for them. On the other hand, somebody who does interviewing—half the day they're talking to people, writing notes about the interview—they may be a perfect candidate for monovision with CK or LASIK. So it's very important for me to understand how they're using their eyes and what it is they want to be able to do to find out what's going to be good for them.
How long does it take to recuperate from these surgeries?
There is some variability in how someone is going to respond, how they're going to heal and the final result that they're going to have. For CK, there is some discomfort for at least one or two days afterwards. Pain and discomfort varies, so it is often hard to predict, but most patients are back to their normal function within the following week. Recovery from laser surgery is similar. There is a little less discomfort, but complete visual recovery takes a little while.
Why do some patients still need glasses after surgery?
One of the things you are going to discuss with your surgeon is what are the chances that you will need glasses for some activities. There are some patients who do not get full correction, so they may still need reading glasses for intensive activities. So they may have good everyday vision for driving a car around town, reading a menu. But they may want to have reading glasses for their very best vision for reading. So if they going to read War and Peace, 1,000-page book, they may want glasses to give them the best vision for both eyes.
Do people ever have to repeat the surgeries?
In general, the results are quite stable, particularly if you are just correcting moderate reading vision. With age, you may need to increase the amount of power you need. So if you correct someone for reading vision, and they're 45, they're going to need more power when they're 55, because aging continues to change your vision. So people need to realize that they may need to come back and do a little bit more because their eyes have aged.