Drop Down MenusCSS Drop Down MenuPure CSS Dropdown Menu
Showing posts with label blindness. Show all posts
Showing posts with label blindness. Show all posts

Wednesday, January 7, 2015

Eye Strain


Eyestrain may result from a need for eyeglasses or from use of out- grown glasses. It may also result from unfavorable conditions under which the eyes arc used.

 Improper lighting, especially for reading or close work, frequent cause of strain

 Do not face the light; it should comefrom theback of you and from the side so you are not in shadow, make sure light bulbs are strong enough (75 to 100 watts) and free of dust. Hold a book or paper about 16 to 18 inches away from you and slightly below eye level. Reading when lying on your back in bed or propped up on an elbow may strain the eyes, and so will reading for long periods in a vibrating vehicle. Avoid glare, of course. 

And rest your eyes from time to time by shifting focus, looking off into the distance. Night Blindness Inability to see well or at all in dim light can mean something wrong not alone with the eyes but with the entire system. Night blindness, as it is called, is a threat to safety, particularly on the highway, because a driver may have 20/20 vision and not realize that his vision is somewhat impaired at night. The condition produces no discernible changes in eye tissues, so it cannot be diagnosed unless the patient tells the physician that he has difficulty in reading road signs at night or has trouble picking out objects in dimly lighted streets. 

It is not normal to have trouble seeing in dim light after a brief period, two to three minutes, of adjustment. If you become aware of such a problem, discuss it with your physician. It can be treated, sometimes simply by addition of vitaminA to the diet. Sunlight Good sunglasses can protect your eyes if you are in bright sunlight. Poor ones may only add to your troubles if you wear them for long. Don't wear glasses with scratches or irregularities. Some glasses are too lightly tinted to do much good. It's true that good sunglasses are expensive. 

The best have ground and polished lenses, and are worth the investment. Even though you wear sunglasses, do not look directly into the sun. Don't wear the glasses indoors and at night no matter how fashionable it may seem because accidents result from the reduced visual perceptiveness. If you use regular glasses, it is worthwhile to have a pair of sunglasses ground to your prescription rather than clip a pair of possibly inferior sunglasses over your carefully made regular glasses