More than 3 million adult Americans have glaucoma, making it one of the leading causes of blindness in the U.S.
The most common form, chronic open-angle glaucoma, generally appears in middle age and seems to have a genetic component: One in five people with glaucoma has a close relative with the condition. In chronic, open-angle glaucoma, sight begins to fade in the outer areas (peripheral) of the visual field; if untreated, tunnel vision and then blindness follow.
The inside of the eye continuously...
Eyes with vision problems do not focus light where they should. Eyeglass lenses change the direction of light entering the eyes so that it focuses properly on a special part of the back of the eye known as the retina.
How Often Do You Need a New Prescription for Eyeglasses?
Call your eye doctor for an exam if your vision changes. But you should also expect to have eye exams regularly as an essential part of maintaining healthy vision. This is especially important since your eye doctor also checks for eye diseases and disorders.
The Basics of Eyeglasses
Eyeglasses may be prescribed with lenses providing:
One vision correction for all distances (unifocal)
Correction for both near and distant vision (multifocal: bifocals, trifocals, progressive, or no-line lenses)
Ultraviolet (UV) light protection -- a lens coating to block the sun's damaging and invisible UV rays
Antireflective coating to lessen light reflection off your glasses, reducing daytime glare and the nighttime "starburst" effect around lights
You may want to ask your eye doctor about other lens enhancements, such as:
Photochromatic lenses, which darken in situations where you'd otherwise wear sunglasses and act as "regular" eyeglasses in normal (usually indoor) light
Scratch protection (recommended for plastic lenses)
Tints -- typically cosmetic but also useful for people whose eyes are sensitive to light
Eyeglass frame styles change with fashion. Frames may be made from:
A combination of plastic and metal
"Specialty" metals such as titanium and carbon graphite, both highly damage resistant
Eyeglass alert! Your new eyeglasses should feel -- well, almost as if you aren't wearing them! They shouldn't rub uncomfortably against your ears or nose, fall off easily, or otherwise not feel "right." Of course, allow a reasonable amount of time for getting used to them. However, if problems persist, let your eye doctor know.