Robert K. Maloney (Ophthalmologist) gives expert video advice on: Which type of eyeglass lenses will correct my vision?; Should I get an antireflective coating applied to my eyeglasses?; Are drug-store brand eyeglasses safe? and more...
What are the primary types of vision correction?
here's three basic ways to correct your vision: glasses, contacts, or surgery.
Which type of eyeglass lenses will correct my vision?
There are a lot of different kinds of eyeglasses. The most common are what we call single-vision. That's just one prescription, the kind you typically get when you're under 40, that help you see far away or read. As you get over 40 and start to lose your reading vision, you need what we call bi-focals or multi-focals. The top part has a distance prescription, and the bottom part has a reading prescription so you can see far away and read still.
Are there advantages or disadvantages to progressive lenses?
As we get into our forties and start losing our reading vision, people get what we call multifocal lenses or progressive lenses. That's a lens with one prescription on the top for distance and a different prescription down below for reading. Now, normally bifocals have a line across separating those two zones, but you can get progressive lenses where that line is blurred out. People like that because that line is a sign of age. It's like putting a sign around your neck that says "Grampa", or "Grandma", and a lot of people don't like that. So progressive lenses cosmetically are very nice. They also have the advantage in that between the top and the bottom is an intermediate zone that's very good for computer. The disadvantage of progressive lenses is that the field of vision is not as wide, and so if I'm looking at you, the vision's clear straight ahead but off to the side, it's not quite as clear so I have to turn my head. And that's just a little bit inconvenient, you have to take some getting used to. But most people adapt to that, so the choice of bifocals versus progressives depends on cosmetics and on your comfort adapting your head movements to a limited field of view.
What type of material should my eyeglasses be made of?
There's different materials you can get lenses made out of. They can be out of plastic glass, different kinds of plastic, different kinds of glass. The choice of material depends on your lifestyle. For example, glasses made of polycarbonate are the safest, because polycarbonate's very impact resistant. It will prevent things from hitting your eyes. Unfortunately, polycarbonate scratches relatively easily. Now there are other plastic materials which aren't as impact resistant, but are much harder to scratch. There're quite nice for scratch resistance. Plastic lenses tend to be lighter than glass, so they don't tend to put dents in your nose as much. Glass lenses, on the other hand, are nice because they can be made very, very thin. So if you don't like people seeing the thick edge of your glasses, if you're highly nearsighted, a glass lens can make that thinner. So the choice of which lens to get depends on cosmetics and lifestyle both.
What are "photochromic lenses"?
You can get what we call photochromic lenses. These are lenses that turn dark outdoors, they turn to sunglasses, and when you come indoors they turn light again. Photochromic lenses work very well if you don't want a separate pair of prescription sunglasses. There's all sorts of bells and whistles you can get on glasses, and which you choose just depends on personal preferences.
Should I get an antireflective coating applied to my eyeglasses?
Now glasses have lots of bells and whistles too, including antireflective coating. You can get non-glare coatings over the surface of the glass. That really doesn't reduce glare for you, but when people look at you they don't see glare off your glasses. They can see your eyes a little more clearly. So it's cosmetically nice.
What should I consider when picking eyeglass frames?
The choice of frames mostly is a cosmetic issue. What's most comfortable? What do you like best on your face? The one thing to keep in mind though, is that the bigger the frame, the more lens is in it, and the heavier they are. So if you're one of those people who gets pressure on your nose, or dents in your nose, go with a smaller frame so you can get lighter lenses. It'll be more comfortable.
Are drug-store brand eyeglasses safe?
If you go to the drugstore, you'll see whole racks of reading glasses. The question is, are they safe? Well, the truth is they work just fine. Especially if your distance vision is very good, probably all you need is one of those little pair of glasses from the drugstore. It's important to know they will not weaken your eye or harm your eye, even if they're not the right prescription for your eye, so they can't do any harm.
Will I become too dependent on my eyeglasses?
Wearing glasses will not make you more dependent on glasses nor will wearing glasses weaken your eyes.