As such some of what we see is just the brains interpretation of sensations from the eye structure and the pressure applied to it. Try rubbing your closed eyes and you will see what I mean. Always remember that the number one job of the brain is pattern recognition.
Emphysema is a form of chronic (long-term) lung disease, usually caused by smoking. Because of lung damage, people with emphysema have difficulty blowing air out. The major symptom of emphysema is shortness of breath.
The main cause of emphysema is smoking. The tiny air sacs or alveoli at the bottom of the lungs, which cover a huge lung area, are surrounded by tiny blood vessels. Here, as the oxygen reaches the alveoli, it is absorbed by the blood vessels and then transferred into the bloodstream and to the rest of the body.