The Positive: 1  Exercises using a cable puts muscles under a constant tension. With free weights, the angle of joints are often changing, thus the resistance on the muscle is also changing. 2  Cable machines can be extremely versatile. They can be used for a wide range of exercises through complete ranges of motion.
As these blood vessels leak fluid, they damage retinal cells. Over the course of days or weeks, scar tissue forms, creating a blind spot in the center of your vision. Although wet AMD occurs in only about 10 percent of cases, it's responsible for nearly 90 percent of severe vision loss from this disease.
Retinitis pigmentosa is a hereditary degeneration of the retina, the light-sensing tissue at the back of the eye, which can lead to tunnel vision. Retinal detachment, in which the retina detaches from the underlying blood vessels that supply it with oxygen and nutrients, can also cause peripheral vision loss.